untitled

PRACTICAL GASTROENTEROLOGY • JULY 2006

The Hitchhiker’s Guide to

Parenteral Nutrition Management

for Adult Patients

INTRODUCTION

eeding nutritionally compromised patients has

never been as easy, or as hard, as it is today. We

are able to provide nutrients parenterally and

enterally to patients who once would have been con-

sidered “unfeedable.” Today’s inpatient population is

sicker than patients in the past; the same may be said

for patients needing specialized nutrition support. This

results in challenges to clinicians caring for these

patients. Our goal in writing this article is to provide a

succinct and easy to follow guide for practicing clini-

cians ordering parenteral nutrition.

INDICATIONS

The guiding principle of nutrition support is to use the

least invasive and most physiologic method of feeding.

Infusing chemicals directly into the bloodstream is the

least preferred method of providing nutrition support

(1). Yet, for a select subset of the population, intra-

venous infusion of central parenteral nutrition (PN) or

peripheral parenteral nutrition (PPN) is the only viable

means to provide substrates for metabolism. PN carries

with it inherent risks associated with the placement of a

central venous catheter. Due to the increased risk of

complications with PN therapy, including thrombosis

and infection, a careful assessment of PN appropriate-

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

Howard Madsen, RD, Pharm.D., Nutrition Support

Pharmacy Practice Resident and Eric H. Frankel,

MSE, Pharm.D., BCNSP, Nutrition Support Coordina-

tor, Covenant Health System, Lubbock, Texas.

Carol Rees Parrish, R.D., M.S., Series Editor

While parenteral nutrition is a life-saving modality for people with intestinal failure, it

is not without significant risk. In the hospital setting, under certain clinical circum-

stances, patients will also benefit from the use of parenteral nutrition. The purpose of

this article is to aid the clinician in the safe provision of parenteral nutrition support,

including development of the prescription, appropriate monitoring, and awareness of

the issues involved in the preparation and stability of commonly used additives.

Frequently asked questions and challenges that arise with the use of parenteral nutri-

tion are also addressed.

Howard Madsen Eric H. Frankel

ness should precede placement of a central venous

catheter (1,2). Table 1 lists indications and contraindi-

cations for PN.

PATIENT ASSESSMENT

Prior to initiating PN, a nutrition assessment is neces-

sary to determine nutrient needs and to anticipate any

metabolic changes that may occur due to the patient’s

underlying condition, medications or concurrent thera-

pies, etc. Table 2 provides a list of factors to consider

when assessing a patient’s nutritional status. Deter-

mining energy and protein needs in the severely mal-

nourished patient under physical stress, often ventila-

tor-dependent with little mobility, can be difficult.

Critical illness brings further challenges in determin-

ing the appropriate calorie level, as matching caloric

expenditure to caloric provision may be detrimental—

providing lower calorie levels initially has been advo-

cated (3,4). Calorie requirements often increase in

relation to stress, fever, and seizures, while a decrease

in needs may be seen in the setting of sedation or

reduced mobility. While indirect calorimetry is consid-

ered the “gold standard” to determine caloric expendi-

ture, formulas and calculations are frequently used.

Unfortunately, no studies to date have demonstrated

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 1

Indications, Relative Indications and Contraindications

for Parenteral Nutrition

Parenteral nutrition is usually indicated in the

following situations

• Documented inability to absorb adequate nutrients via the

GI tract such as:

– Massive small-bowel resection/short bowel syndrome

(at least initially)

– Radiation enteritis

– Severe diarrhea

– Untreatable steatorrhea/malabsorption (i.e., not pancre-

atic insufficiency, small bowel bacterial overgrowth, or

celiac disease)

• Complete bowel obstruction, or intestinal pseudo-obstruction

• Severe catabolism with or without malnutrition when GI tract

is not usable within 5–7 days

• Inability to obtain enteral access

• Inability to provide sufficient nutrients/fluids enterally

• Pancreatitis accompanied by abdominal pain with jejunal

delivery of nutrients

• Persistent GI hemorrhage

• Acute abdomen/ileus

• Lengthy GI work-up requiring NPO status for several days in

a malnourished patient

• High output enterocutaneous fistula (>500 mL) and inability

to gain enteral access distal to the fistula site

• Trauma requiring repeat surgical procedures

Parenteral nutrition

may

be indicated in the following situations

• Enterocutaneous fistula

• Inflammatory bowel disease not responding to medical therapy

• Hyperemesis gravidarum when nausea and vomiting persist

longer than 5–7 days and enteral nutrition is not possible

• Partial small bowel obstruction

• Intensive chemotherapy/severe mucositis

• Major surgery/stress when enteral nutrition not expected to

resume within 7–10 days

• Intractable vomiting when jejunal feeding is not possible

• Chylous ascites or chylothorax when low fat/fat free EN does

not adequately decrease output

Contraindications for Parenteral Nutrition

• Functioning gastrointestinal tract

• Treatment anticipated for less than 5 days in patients without

severe malnutrition

• Inability to obtain venous access

• A prognosis that does not warrant aggressive nutrition support

• When the risks of PN are judged to exceed the potential

benefits

Used with permission from the University of Virginia Health System

Nutrition Support Traineeship Syllabus (Parrish CR, Krenitsky J,

McCray S). Parenteral Module. University of Virginia Health System

Nutrition Support Traineeship Syllabus, 2003.

Table 2

Important Factors to Consider when Assessing a Patient

for Parenteral Nutrition

• Anthropometric Data – include:

– Recent weight changes

– Current height and weight

• Lab values – including:

– Comprehensive metabolic panel

– Serum magnesium level

– Serum phosphorus level

– Serum triglycerides as indicated (Table 18)

• Medical/Surgical History

– Anatomy (resections)/ostomies

– Pre-existing conditions such as diabetes, renal failure,

liver disease, etc.

• Diet/Medication History – include:

– Food/drug allergies

– Diet intake prior to admission

– Special diets

– Herbal/supplement use

– Home and current medications

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

benefit by comparing the use of metabolic cart results

with various formulas in terms of clinical outcomes.

Regardless of which calculation is used to estimate

nutrient requirements, it is important to note that there is

a lack of evidence correlating a given calorie and pro-

tein level to clinical outcomes, and the controversy over

which formula is “best” is ongoing. Guidelines for

designing PN formulations have been developed by var-

ious organizations and experts in the field of specialized

nutrition support, some of which are listed on Table 3.

VENOUS ACCESS

Line type, nutrition formulation and other medication

needs are inter-related and need to be approached in a

unified manner. Table 4 describes the advantages and

disadvantages of intravenous access typically used for

parenteral nutrition support. Nutritional limitations

associated with those lines are also provided. Further

details on these topics have been included in the follow-

ing paragraphs.

PERIPHERAL NUTRITION SUPPORT (PPN)

Peripheral access is sometimes used for patients who

need short-term (<2 weeks) nutrition support. Because

of the high volume of fluid needed, patients requiring

fluid restriction are not candidates for this type of ther-

apy. In order to meet a patient’s nutritional needs using

PPN, infusion rates greater than 150 mL/hr may be

required; this limits the use of PPN to patients with nor-

mal renal, cardiac, hepatic, and pulmonary function.

Due to the risk of thrombophlebitis, these solutions are

generally limited to an osmolarity of <600–900

mOsm/L (12,14). See Table 5 and Table 6 for calcula-

tion of mOsm in parenteral solutions. Even at 600–900

mOsm, these solutions are hypertonic, hence any

patient with poor peripheral access should not receive

PPN. Instead, alternatives should be considered, based

on the individual patient’s circumstances. These

include the use of Central PN or provision of peripheral

protein-sparing IV fluids containing 5% dextrose. The

anticipated duration of parenteral support and how

soon the patient may be transitioned to enteral nutrition

will factor into this decision. Patients with rapid or fre-

quent loss of peripheral access with IV fluids (D

, etc.)

are poor candidates for PPN. As a rule of thumb, if the

patient’s peripheral access has been changed 2–3 times

within the first 48 hours following admission on stan-

dard IV fluids, PPN should not be attempted. Combi-

nations of heparin and hydrocortisone added to the PPN

formulation, with or without the use of a nitroglycerin

patch placed proximal, and as close as possible to the

catheter site, have been used to extend the viability of

peripheral catheters (16–18) (Table 7).

Peripheral lines should be changed every 48–72

hours to minimize the risk of infection and throm-

bophlebitis (13). PPN avoids the inherent risks associ-

ated with central venous access, but is not suitable

unless the patient meets the criteria in Table 8. Patients

not meeting these criteria and needing intravenous

(continued on page 51)

Table 3

Daily Energy and Substrate Guidelines for Adult PN (5–8)

Nutrient Acute Care Critical Care

Energy 25–30 total kcals/kg/d 25 total kcals/kg/d

• Refeeding 15–25 kcal/kg/d 15–25 kcal/kg/d

• Obesity (≥130% IBW) 15–20 kcal/kg/d adjusted weight * 15–20 kcal/kg/d adjusted weight *

Protein 0.8–1.0 g/kg/d maintenance 1.5–2.2 g/kg/d

1.2–2.0 g/kg/d catabolism

Dextrose <7 g/kg/d <5 g/kg/d

Lipid** <2.5 g/kg/d 0.4–0.75 g/kg/d

*Adjusted weight based on a 50% correction factor ([usual weight – ideal body weight] × 0.50)

**If a patient is to be on PN for greater than 3 weeks, a minimum of 2%–4% of total calories should come from IV fat emulsion (IVFE)

including linoleic acid to prevent essential fatty acid deficiency (EFAD) (9)

Table 4

Review of Access Devices Used for Nutritional Support (10–13)

Line Type Advantages Disadvantages

Peripheral Lines

Peripheral – Short • Least expensive • Loss of line is common. High levels of phlebitis

• Easily placed and removed and vein damage with nutrition support

• Lowest risk for catheter related infections • Kcals usually limited due to volume restriction

• Beneficial for patients needing short term • Limited to one lumen

nutrition support (<1 week) • Limits infusion osmolality to 600–900 mOsm/L and

• Need to change frequently (48–72 hours) infusion pH between 5 and 9 (lower limit of mOsm

represents INS standards)

Peripheral – Midline • May be used for a longer duration than peripheral • Must maintain guidelines for peripheral lines when

catheters looking at concentration and pH

• Ease of placement compared to central lines • Not a central line

• Allows access to larger vessel

Central Lines

Peripherally Inserted • Able to infuse solutions >900 mOsm/L • Not as long term as other centrally placed catheters—

Central Catheters or • May be placed by trained RN length of stay ~ a year

(PICC) lines • Decreased rate of infection when compared to other • More difficult self care if located in anticubital

central lines in home care patients position (should not be painful)

• Able to place lines with multiple lumens • Blood sampling not always possible

• Many PICC lines can be used for CT contrast injection • More frequent flushing and maintenance required

• More pain is associated

Hickman

, and • Able to give solutions >900 mOsm/L • Surgical procedure, more difficult to place involving

Broviac

• Provide full nutritional support via IV route increased cost and monitoring as well as risk to

• Able to place lines with multiple lumens patient. Adds additional time and complexity in

• Able to remain in place for extended time periods placement

(1–3 years usual) • Removal also more involved than PICC removal,

due to tunnel

• Catheter protruding from chest may affect some

people’s self image

Groshong

Catheters • Able to give solutions >900 mOsm/L • Surgical procedure, more difficult to place involving

• Provide full nutritional support via IV route increased cost and monitoring and risk to patient

• Able to place lines with multiple lumens. • Adds additional time and complexity in placement

• Able to remain in place for extended time periods • Removal also more involved than PICC removal,

• May be “locked” with normal saline due to tunnel

• Catheter protruding from chest may affect some

people’s self image

Femoral Lines • Gives IV access to patients with no other option • Increased infection risk

Multiple Lumen acute • Economical, can be removed by trained RN • Increased infection rate compared to single lumen

care catheters • May be placed at bedside or in radiology by a and tunneled catheters. Usually not repairable

physician if damaged

• Should not be used in home care, for acute care only

• Short dwell time, 1–2 weeks

Port • Long term use with lowest infection risk of all • Placement and removal are surgical procedures

options (dwell time may be years) performed in the operating room or interventional

• Site care only when accessed suite

• Body image intact • Requires “stick” to access port with Huber needle.

• Ideal for intermittent access If needle is in place, risk of infection increases

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued from page 48)

PRACTICAL GASTROENTEROLOGY • JULY 2006

nutrition are candidates for central PN.

Several conveniently packaged, “fixed concentra-

tion” PPN products are available commercially and are

suitable for peripheral administration. These formula-

tions contain dextrose ranging from final concentra-

tions of 5%–10% or 3% glycerol in addition to amino

acids in final concentrations of 3% to 4.25%. Some of

these products are available with or without a standard

amount of electrolytes. PPN formulations can also be

compounded on an individual basis (customized)

allowing the flexibility to add intravenous fat emul-

sions (IVFE) or manipulate electrolytes. IVFE are not

included in commercial premixed formulations, but

10% or 20% concentrations of IVFE may be given as

a piggyback. All IVFE are isotonic and lower the over-

all osmolarity of the infusate. Some clinicians will pro-

vide up to 60% of the total caloric requirements as

lipid, while others limit the lipid to less than 1

gm/kg/day due to the possibility of altered immune

function associated with infusion of long chain triglyc-

erides (19). Patients on IVFE should be monitored for

Fat Overload Syndrome; a syndrome characterized by

hypertriglyceridemia, fever, clotting disorders, hepato-

splenomegaly, and variable end organ dysfunction.

This syndrome has been reported in the setting of

excessive IVFE administration to children and criti-

cally ill adult patients (20,21). This is particularly

important in the critical care setting where the seda-

tive, propofol (Diprivan

and two generic versions), a

medication in a 10% IVFE base, is frequently used.

CENTRAL NUTRITIONAL SUPPORT

Central venous catheters provide temporary or long-

term access to large diameter veins with blood flows in

the range of 2–6 L/min. This rapid blood flow allows

infusion of formulations with osmolarities in excess of

900 mOsm/L (central solutions range from ~1500–

2800 mOsm/L). Central venous access devices include

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 5

One Method to Calculate Osmolarity of IV Admixtures

1. First, multiply the gm, mEq or mL by the mOsm/unit listed

in Table 6

2. Add all the multiplied values to determine the total mOsm

for the mixture

3. Add each volume in the formulation to give a total in liters

4. Divide the total mOsm by the total volume in liters to deter-

mine the mOsm/L of the formulation

Table 6

Milliosmoles of Selected Additives (15)

Additive mOsm/Unit

Sterile Water 0.00

Dextrose Options (3.4 cal/g)

Dextrose 5, 10, 30, 50, 70% ~5 mOsm/g

Amino Acid Options (4 cal/g)

Amino Acid 8.5, 10, 15% ~10 mOsm/g

Intravenous Fat Emulsion (IVFE) Options

10% (1.1 cal/mL)

20% (2.0 cal/mL) ~0.280 mOsm/mL

30% (3.0 cal/mL)

Micronutrients

Calcium Gluconate 0.662 mOsm/mEq

Magnesium Sulfate 1 mOsm/mEq

Multi-trace Elements (MTE-5) 0.36 mOsm/ml

MVI infusion Concentrate (MVI-12)41.1 mOsm/dose

Potassium Acetate 2 mOsm/mEq

Potassium Chloride 2 mOsm/mEq

Potassium Phosphate 2.47 mOsm/mM

Sodium Acetate 2 mOsm/mEq

Sodium Chloride 2 mOsm/mEq

Sodium Phosphate 4.0 mOsm/mM

Table 7

Peripheral Parenteral Nutrition “Vein Protector” (16)

• Hydrocortisone, 15 mg

• Heparin, 1500 units

• Plus: transdermal nitroglycerin (NTG) patch, 0.1 mg/hour

Table 8

Criteria for use of Peripheral Parenteral Nutrition

• Nutritional needs <1800 kcals per day

• Patient requires less than 10 to 14 days of intravenous

nutrition

• Peripheral venous access is available (good peripheral veins)

• Requires only one intravenous line with intravenous fat

emulsion (IVFE) administration via piggyback infusion

• Fluid restriction is not an issue

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Groshong

, Hickman

, Hohn

, multiple lumen

catheters, peripherally inserted central catheter (PICC)

lines, and implanted intravenous port devices. Many

central catheters provide multiple lumens; if multiple

lumens exist, a single lumen should be designated for

PN use only (22). The distal lumen is usually the largest

diameter and can be reserved for blood transfusions and

blood sampling. Central catheters are the route of choice

for patients with fluid management issues, such as con-

gestive heart failure (CHF) or renal failure, patients with

poor peripheral venous access and those requiring PN

>10–14 days, assuming they meet criteria for PN use.

DESIGNING THE FORMULATION

Macronutrients

Carbohydrate

Carbohydrate is generally provided in amounts up to

60% of total kcals/day. In the hospitalized patient, ini-

tial dextrose in PN solutions should not exceed 7.2

g/kg/day (5 mg/kg/minute) to minimize the occurrence

of fatty liver and hyperglycemia (23). However, in sta-

ble, hospitalized or home patients receiving cycled PN,

the glucose infusion rate may exceed 5 mg/kg/minute

when the patient might require additional calories for

weight maintenance or gain.

Protein

Protein (amino acids) is typically supplied in the range

of 1.5 g protein/kg/day depending on the amount of

stress and catabolism present. Critical care, post-surgi-

cal, burn, dialysis and many other types of hospitalized

patients often require protein administration in the range

of 1.2–2 g/kg/day. In severe catabolic states, protein

needs may be as high as 2–2.5 g/kg/day (24). Acute

renal failure often demands high protein supplementa-

tion, from 1.5–1.6 g/kg/day due to protein losses

through the glomeruli, dialysis or catabolism (25).

Alternatively, in times of renal insufficiency or failure

when a patient is not yet dialyzed and has rising blood

urea nitrogen concentrations, a decrease in protein to 0.8

(continued on page 56)

Table 9

Commercially Available Crystalline Amino Acid Solutions

Brand Name Type/Indication Stock Concentrations

Aminosyn II™ Standard 3.5%, 4.25%, 5%, 7%, 8.5%, 10%

Travasol™ Standard 3.5%, 4.25%, 5.5%, 8.5%, 10%

Aminosyn II™ Standard/fluid restriction 15%

Clinisol™ Standard/fluid restriction 15%

Novamine™ Standard/fluid restriction 15%

Prosol™ Standard/fluid restrictions 20%

Hepatamine™ Hepatic failure 8%

Hepatasol™ Hepatic failure 8%

Aminosyn HBC™ Metabolic stress 7%

Freamine HBC™ Metabolic stress 6.9%

Branchamin™ (Contains only leucine, isoleucine and valine Metabolic stress 4%

use to supplement standard amino acid base)

Amino PF™ Pediatric 7%, 10%

Trophamine™ Pediatric 6%, 10%

Aminess™ (Essential amino acids plus histidine) Renal 5.2%

Aminosyn RF™ (Essential amino acids plus arginine) Renal 5.2%

Nephramine™ (Essential amino acids plus histidine) Renal 5.4%

Renamin™ (Essential and some non-essential amino acids) Renal 6.5%

Adapted from Barber JR, Miller SJ, Sacks GS. Parenteral feeding formulations. In: Gottschlich MM, Ed.

The Science and Practice of Nutrition Support: A Case-Based Core

Curriculum.

Dubuque, IA: Kendall/Hunt Publishing Co.;2001: 251–268 with permission from the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.).

A.S.P.E.N. does not endorse the use of this material in any form other than its entirety.

PRACTICAL GASTROENTEROLOGY • JULY 2006

gm/kg may avoid uremic complications (26). However,

if total kcals are inadequate to support protein utilization

or glucose is poorly controlled, catabolism of endoge-

nous protein (lean body mass) will render this interven-

tion useless. Of note, dietary protein only comprises

25% of the nitrogen pool that is turned over each day.

Hence, a change in protein from 1.3 down to 1 g/kg/day

in a 75 kg patient represents a mere decrease of 22 g

protein/day. GI bleeding, hyperglycemia and the obliga-

tory catabolism of trauma/sepsis would generate appre-

ciably more urea than this “additional” 22 grams of pro-

tein/day. In the past, restricting protein in patients with

liver failure was the standard practice; however, it is

now accepted that this may worsen the underlying liver

disease, and does not aid hepatic encephalopathic

episodes. For very nice reviews of protein

in liver and renal disease, see references 27

and 28. Table 9 describes the commonly

available amino acid products and their

characteristics.

To Count, or Not to Count Protein

as Calories?

Total calories are used to characterize oral

diets and tube feeding products. Charac-

terizing the PN prescription as protein and

non-protein calories does not make physi-

ological sense (29,30). The use of non-

protein calories for calculations presumes

that one can direct protein utilization.

Consider: When you provide amino acids to a catabolic

patient, oxidation rates may equal or exceed amino acid

infusion rates. There are multiple pathways taken by

amino acids; utilization of substrate at the cellular level

is not limited to a single pathway. Mixed fuel utilization

will always take place, although the relative amounts of

each substrate may change.

Fat

Intravenous fat emulsions (IVFE), (formerly called

lipid emulsions), are generally used to provide

20%–30% of daily kcals unless conditions exist which

prohibit or complicate lipid administration of this

amount, i.e. hypertriglyceridemia or propofol infu-

sions. Note that the vehicle for propofol is 10% IVFE

and it provides essential fatty

acids, calories (1.1 cal/mL

infused) and vitamin K (31).

See Table 10 for commercial

lipid emulsions available in

the U.S and their vitamin K

content. The content of vita-

min K varies depending on

the manufacturer and con-

centration, with safflower oil

containing less vitamin K

than soybean oil. Vitamin K

typically increases propor-

tionally with increasing lipid

concentrations (example,

viatmin K content doubles

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued from page 53)

Table 10

Energy and Vitamin K Content of Commonly Used IVFE (32–35)

Soybean Oil Safflower Oil Vitamin K

Lipid Emulsion Kcals/mL* g/L g/L mcg/dL

Intralipid 10% 1.1 100 0 30.8

Intralipid 20% 2 200 0 67.5

Intralipid 30% 3 300 0 93

Liposyn II 10% 1.1 50 50 13.2

Liposyn II 20% 2 100 100 26

Liposyn III 10% 1.1 100 0 31

Liposyn III 20% 2 200 0 62

Liposyn III 30% 2.9 300 0 93

*Kcals/mL differ according to lipid and glycerol content of IVFE

Table 11

Normal Serum Electrolyte Values and Parenteral and Enteral Ranges (36–38)

Normal Serum Parenteral Adult Enteral

Electrolyte Range* Intake Range Requirements

Sodium 135–145 mM/L 0–200 mEq/L 100–150 mEq/day

Chloride As needed to maintain acid-base balance

Potassium 3.5–5.1 mM/L 0–240 mEq/day 60–120 mEq/day

Acetate** As needed to maintain acid-base balance

Phosphate 2.3–4.7 mg/dl 0–60 mM/day 15–30 mM/day

Magnesium 1.7–2.5 mEq/L 0–48 mEq/day 8–24 mEq/day

Calcium 9.2–11.0 mg/dl

(ionized calcium

0.8–1.2 mEq/L) 0–25 mEq/day 9–22 mEq/day

*Note: Normal lab values vary between institutions and the populations they serve.

**Acetate is converted to bicarbonate in the liver.

with an increase from 10% to 20%) (32–34).

Micronutrients

Electrolytes in PN formulations are added according to

anticipated patient requirements, metabolic response to

medications, and recommended daily intakes. Table 11

provides typical ranges for parenteral electrolyte content.

Excessive electrolyte losses from wounds, GI suction,

surgical drains, fever (sweat loss), emesis, and diarrhea

need to be replaced in the PN formulation or other IV

solutions. Table 12 provides the approximate electrolyte

composition and volume of many body fluids.

Vitamins and trace elements are usually added as

commercially prepared multivitamin and trace metal

“cocktails,” which may meet daily requirements and

prevent toxicity. Table 13 reviews the current recom-

mendations for parenteral multivitamin injections by

the Food and Drug Administration (FDA) (39).

The short term (<1 week) PN patient rarely needs

supplementation of Vitamin K, while the long-term

patient requiring PN for weeks to months will likely

require 2–4 mg/week of parenteral vitamin K (40,41).

The newest commercial vitamin products, Infuvite

(Baxter Healthcare Inc, Deerfield, IL), and MVI-Adult

(Mayne Pharma (USA), Paramus, NJ) were formulated

to meet the latest FDA standards and

include Vitamin K. Mayne Pharma

manufactures a product that does not

contain vitamin K (MVI-Adult without

vitamin K

), but use of this product is

not necessary, as even patients on

coumadin need some vitamin K. It is

important to remember, however, that

wide fluctuations in vitamin K intake

have significant impact on the effects of

coumadin, and thus, intake should

remain consistent when patients are

placed on this anticoagulant (42). As

previously discussed, IVFEs also con-

tain vitamin K and may contribute sig-

nificant amounts depending on the oil

used, rate of infusion and concentration

of lipid (Table 10).

General trace element dosing

guidelines are listed in Table 14. There

is some concern that the recommended

manganese dose may be excessive for long-term PN

patients. Periodic monitoring is recommended to

ensure whole blood manganese levels remain within

safe limits for patients receiving PN (44). When con-

sidering the dosing of multivitamins and trace ele-

ments, adjustments may need to be made in certain set-

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 12

Approximate Electrolyte Composition of Various Body Fluids (36)

Electrolytes (mEq/L)

Source Volume (mL/d) Na K HCO

Saliva 500–2000 2–10 20–30 30 8–18

Gastric 2000–2500

pH<4 60 10 — 90

pH>4 100 10 — 100

Pancreatic 1000 140 5 90 75

Bile 1500 140 5 35 100

Small Bowel 3500 100 15 25 100

Colonic — 60 30 — 75

Diarrhea 1000–4000 60 30 45 45

Urine 1500 40 0 — 20

Sweat 1500 50 5 — 55

Reprinted from Matarese LE. Metabolic complications of parenteral nutrition therapy. In: Gottschlich MM, Ed.

The Science and Practice of Nutrition Support:

A Case-Based Core Curriculum.

2001;269-286, with permission from the American Society for Parenteral

and Enteral Nutrition (A.S.P.E.N.). A.S.P.E.N. does not endorse the use of this material in any form other

than its entirety.

Table 13

Recommended Daily Intake of Intravenous Vitamins (39)

FDA/AMA/NAG*

Vitamin Recommended amounts/day

Thiamin (B1) 6 mg

Riboflavin (B2) 3.6 mg

Pyridoxine (B6) 6 mg

Cyanocobalamin (B12) 5 mcg

Niacin 40 mg

Folic Acid 600 mcg

Pantothenic acid 15 mg

Biotin 60 mcg

Ascorbic acid (C) 200 mg

Vitamin A 3300 IU

Vitamin D 5 mg

Vitamin E 10 IU

Vitamin K 150 mcg

*National Advisory Group on Standards and Practice Guidelines for PN (ASPEN)

PRACTICAL GASTROENTEROLOGY • JULY 2006

tings. For example, in the presence of cholestatic liver

disease, reductions in manganese and copper are often

necessary (45,47).

Medications

A variety of medications may be added to PN solu-

tions, however, only insulin and H

-antagonists will be

considered here. A recent review is available else-

where (48).

Insulin

Hyperglycemia is the most common complication of PN.

Regular human insulin is commonly added to PN to aid

in blood glucose control. For a patient previously requir-

ing insulin, addition of 1 unit of regular insulin per 10 g

dextrose to the PN admixture is a safe, conservative

starting point. If fasting blood glucose concentrations

prior to PN initiation are running consistently >200

mg/dL, then a greater ratio of insulin to carbohydrate

may be appropriate (e.g., 1.5–2 units per 10 g dextrose).

Sliding scale coverage with regular or one of the more

rapid acting insulin analogs such as insulin lispro

(Humalog

) or insulin aspart (Novolog

) should be

added to the medication regimen of the PN patient to

provide additional coverage where needed. However,

these insulin analogs are not compatible with PN formu-

lations and thus only regular human insulin can be added

into the PN admixture. The monitoring interval for blood

glucose should be based on the duration of action of the

insulin product. Elevated blood glucose levels can gen-

erally be controlled within a few days of PN by adding

70%–100% of the sliding scale insulin given during the

time of the previous PN formulation. When following

this method, success of the sliding scale ultimately

depends upon changes in patient condition, medications,

and initiation of an oral diet or enteral nutrition.

Patients need to be closely monitored for blood

glucose variations after insulin has been adjusted in a

PN formulation. Some clinicians limit the dose of reg-

ular human insulin in PN to less than 2 units per 10 g

dextrose; however, changing attitudes regarding

glycemic control have prompted modification of this

position depending on the monitoring capability of the

facility. Due to improved patient outcomes associated

with better glycemic control in the intensive care unit,

it is common practice in our institution to target blood

glucose concentrations between 80–130 mg/dL for

most patients (49). The use of an insulin drip or tighter

sliding scale insulin regimen may be more appropriate

in some environments to reduce the risk of hypo-

glycemia, as well as the frustration, personnel time and

costs needed to reformulate PN admixtures if blood

glucose drops too low. When using an insulin drip, the

amount of insulin to be added to the future PN bag can

be calculated as two-thirds of the total insulin infused

during the previous PN administration. This takes into

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued on page 61)

Table 14

Recommended Adult Daily Intake of Intravenous

Trace Minerals (43)

Trace element Amount

Chromium 10–15 mcg

Copper 0.3–0.5 mg

Manganese 60–100 mcg

Selenium 20-60 mcg

Zinc* 2.5–5.0 mg

*Note: Recommended zinc requirement per liter of ostomy or stool output lost:

• 12.2mg/L small bowel fluid

• 17.1mg/kg stool / ileostomy

Adapted from Mirtallo J, Canada T, Johnson D, Kumpf V, Petersen C, Sacks G,

Seres D, Guenter P; Task Force for the Revision of Safe Practices for Parenteral

Nutrition. Safe practices for parenteral nutrition. J Parenter Enteral Nutr, 2004;

28:S39–S70 with permission from the American Society for Parenteral and

Enteral Nutrition (A.S.P.E.N.). A.S.P.E.N. does not endorse the use of this

material in any form other than its entirety.

Table 15

Common Medications which may Effect

Blood Glucose Levels (51,52)

Hyperglycemia Hypoglycemia

Corticosteroids Flouroquinolones

Diuretics • In particular: Gatifloxacin

Adrenergic agents Insulin

Cyclosporin Alcohol

Tacrolimus Sulfonylureas

Sandostatin Methandrostenolone

Phenytoin Clofibrate

Phenobarbital Cypionate

Lithium B-blockers

Calcitonin Monoamine Oxidase Inhibitors (MAOI)

Rifampin

account the improved bioavailability of insulin when

added to the PN.

Adjusting dextrose concentration in intravenous

nutrition and monitoring for medication effects can

further aid the practicing clinician in blood glucose

control. Lowering dextrose concentrations is one way

to improve glycemic control where needed. IVFE may

be used to provide a greater percentage of the caloric

intake. In the refractory hyperglycemic patient, some-

times PN just needs to be discontinued until eug-

lycemia is achieved (50). Anticipating drug effects on

blood glucose levels helps maintain control. Table 15

lists some medications, which are known to affect

blood glucose levels. Illness, stress, and activity of the

patient may also play a role and must be considered

when adjusting glucose management. Table 16 pro-

vides additional suggestions to aid in blood glucose

control.

-antagonists

antagonists are often added to the PN admixture in

patients requiring gastrointestinal stress ulcer prophy-

laxis. Famotidine is a common additive and has been

shown to be stable in 3-in-1 admixtures of various

compositions for at least 72 hours (53). The adult rec-

ommended dose of famotidine is 20 mg dosed every

12 hours, which can be added to PN as 40 mg per 24-

hour bag. Famotidine is renally excreted, therefore, a

50% dose reduction is recommended when a patient’s

creatinine clearance is <50 mg/min. Ranitidine may

also be added to PN formulations. It is stable in 3-in-1

solutions for 24 hours, however more than 10% of the

drug may be lost at 48 hours (54). The adult recom-

mended dose is 200–300 mg daily, generally not to

exceed 400 mg per day. Doses should be reduced to 50

mg daily if the creatinine clearance is <50 mg/min

(55). Patients receiving an intravenous or oral proton

pump inhibitor usually do not need a H

-antagonist.

Iron

Iron supplementation may be needed for chronic home

PN patients. Although body stores should last for up to

6 months, deficiencies have been reported after 2

months on PN without supplementation (56). Iron dex-

tran has been used in 2-in-1 PN formulations in doses

of 10–75 mg/day with no apparent side effects (57,58).

However, the addition of iron to 3-in-1 PN admixtures

has not been well studied and reports of incompatibil-

ities exist (58). Anaphylaxis and destabilization of

lipid formulations are both problems associated with

this form of iron, and many clinicians prefer to sup-

plement iron separately from PN solutions. Some of

the newer iron products such as Ferrlecit

(Na ferric

gluconate complex) by Schein and Venofer

(iron

sucrose or iron saccharate complex) by American

Regent may be considered for use separate from PN.

Due to the complexity of PN formulations and the

small market share of the PN population, compatibility

studies of these new iron compounds in PN are

unlikely to ever be performed by the manufacturers.

FREQUENTLY ASKED QUESTIONS

IN THE CLINICAL SETTING

How Should PN Be Initiated?

Although PN infusion rates are often gradually

advanced, there is no real reason to do this. Patients

with diabetes, at a high risk for refeeding, or patients

starting PN at home might benefit from this approach;

however, in the acute care setting, this is not necessary.

Hospitalized patients requiring PN can be started at the

goal rate for the volume to be provided; assuming

measures have been taken to minimize metabolic

response (i.e., patient not overfed).

Hyperglycemia puts the patient at risk for infec-

tion and thwarts utilization of nutrients that the par-

enteral formulation provides. Overfeeding should be

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued from page 58)

Table16

Suggested Strategies for Improving Glucose Control

• Do not overfeed the patient

• Limit dextrose in TPN to 150 g/day initially

• Review other sources of IV dextrose (including CVVHD,

peritoneal dialysis, antibiotic drips, etc.—PN may need to

be adjusted accordingly).

• Increase units of insulin given at each step for sliding scale

coverage

• Increase frequency of glucose checks if necessary (every

4–6 hours)

• Add insulin drip

• Stop TPN for 24 hours and get glucose under control

PRACTICAL GASTROENTEROLOGY • JULY 2006

avoided with any form of nutrition support; dextrose is

usually the macronutrient of most concern with PN;

therefore, if calorie requirements are the reason for a

slow escalation, then the dextrose can be provided at a

fractional amount of the goal and increased as the

patient tolerates. If the PN carbohydrate content has

been limited in anticipation of refeeding, or for the

presence of hyperglycemia, there is no need to also

limit the PN rate or “titrate the rate up” as this would

be “doubly cautious” and unnecessary. Daily reformu-

lations as necessary are based on current lab values

and the response to any changes made previously.

When Should PN Be Discontinued?

PN should be discontinued with transition to PO or

enteral nutrition as soon as feasible. Many patients

may benefit from a trophic enteral feeding while on

PN. Once enteral feedings or PO intake has advanced

to >50% of estimated kcals, and the patient is tolerat-

ing this well, the PN formula can be weaned or dis-

continued. PN can be restarted in 2–3 days if the

patient does not continue to tolerate enteral or PO

nutrition or if intake is less than 50% of estimated

requirements. Attention to glycemic control post-PN is

crucial in those patients who have not previously been

diagnosed as having diabetes mellitus, yet required

insulin with the PN and became hyperglycemic again

once PN stopped. PN therapy may act as a very expen-

sive surrogate glucose tolerance test.

How Should PN Be Tapered?

There is a general belief that PN formulations require

tapering. Rebound hypoglycemia is rarely seen but is

often discussed in the clinical setting (59–61). The risk

is very low, even in patients with diabetes mellitus, as

they are somewhat “protected” by inherent insulin defi-

ciency. Stopping PN with insulin is the same as stop-

ping an independent insulin drip; remember, the half-

life of regular insulin is only 5 minutes (although,

somewhat longer if the patient is in renal failure). A

taper down of PN is not needed, especially if the patient

is receiving another dependable source of carbohy-

drate. If a particular patient is prone to hypoglycemia,

tapering PN over 1–2 hours before discontinuation is

justified and can avoid this problem.

When Should I Be on the Lookout

for Refeeding?

Many hospitalized patients are malnourished due to

the nature of their disease and/or treatment effects.

When initiating nutrition support, it is important to

monitor these patients closely to avoid refeeding.

Refeeding syndrome is characterized by an abrupt

decrease in serum potassium, magnesium and/or phos-

phorus. This results from pancreatic stimulation and

insulin secretion (the driving force behind refeeding)

after the introduction of a consistent nutrient source,

primarily carbohydrate. The clinical presentation of

refeeding syndrome can also include sodium and fluid

retention causing edema, which may result in stress to

the cardiac and respiratory systems. In these patients,

PN should be started at partial, or “refeeding” calories,

especially carbohydrate, with an appropriate supple-

mentation of electrolytes and vitamins as appropriate.

Once the patient is stable, PN can then be advanced to

target as tolerated. A thorough discussion of this topic

is available elsewhere (62).

What Happens If the Patient is Overfed?

While it is natural to want to provide “hyperalimenta-

tion” via the parenteral route for malnourished and

catabolic patients, overfeeding, especially in cases of

previously undernourished patients can cause more

harm than good (see refeeding above). Critically ill

and post-surgical patients often have an “obligatory

hypercatabolism” not correctible by feeding (63).

Overfeeding these patients may increase stress on vital

organs including the heart, liver, and kidneys (64,65).

All PN patients should be monitored closely and

calories rarely need to exceed 30–35 kcal/kg. Indirect

calorimetry may be helpful in some patients to

help determine calorie needs and avoid under, or over-

feeding (66).

Which is Best? 3-in-1 Versus 2-in-1

Many institutions have switched from the traditional 2-

in-1 PN admixtures to a 3-in-1 admixture combining

IVFE into the amino acid/dextrose mix rather than

hanging the IVFE separately. Both systems are avail-

able to the practicing clinician and each has advan-

tages as well as disadvantages. These are reviewed in

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued on page 64)

PRACTICAL GASTROENTEROLOGY • JULY 2006

Table 17.

Intravenous Fat Emulsion Hang Time

The CDC has recommended that due to the potential

for bacterial contamination, 3-in-1 solutions should

not hang for longer than 24 hours. If lipid is hung sep-

arately from the PN formulation such as in 2-in-1 solu-

tions, each container of IVFE should not hang longer

than 12 hours.

Series Editor’s Note:

The Centers for Disease Control and

Prevention issued recommendations in 1982, that “infusions of

lipid emulsions should be completed within 12 hours of start-

ing” (1). This was based on reports of microbial growth in con-

tainers of lipid emulsion that were deliberately-contami-

nated with microorganisms (2). In 1996 the CDC modified

their recommendations to allow lipids in 3-in-1 PN to hang for

24 hours, but restated the recommendation for IV lipid emul-

sions alone to be completed within 12 hours (3). The only

adult study that has compared the 24 hour infusion of IV lipid

emulsions with 3-in-1 PN did not show a significant difference

in infectious complications between groups (4).

In short, the CDC recommendations are based on in-

vitro studies after containers were purposefully contami-

nated. There is absolutely no outcome information in adult

patients that a 24-hr hang-time increases infections. If a 12-

hr hang-time policy means that a nurse manipulates the line

more often, a 12-hr hang-time policy may actually increase

patient infections. The hang-time concern (myth) may be

real for pediatric patients where daily lipid is dispensed

from a large volume container and there is greater potential

for contamination, but the best data we have points to no

more infections with 24-hr hang time than there is with 3-in-

1 in adults.

1. Anonymous. CDC Guideline for Prevention of Intra-

venous Therapy-related Infections. Infection Control,

1982; 3: 52-72.

2. Melly MA, Meng HC, Schaffer W. Microbial growth in

lipid emulsions used in parenteral nutrition. Arch Surg,

1975; 110: 314-318.

3. Pearson ML. Hospital Infection Control Practices Advi-

sory Committee: Guideline for prevention of intravascu-

lar device-related infections. Infection Control Hosp.

Epidemiology, 1996; 17: 438-473.

4. Vasilakis A, Apelgren KN. Answering the fat emulsion

contamination question: three in one admixture vs con-

ventional total parenteral nutrition in a clinical setting. J

Parenter Enteral Nutr, 1988;12(4):356-359.

What is the Best Way to Manage Serum

Electrolyte Abnormalities?

Experience may be the best instructor for adjusting

electrolytes in parenteral formulations. Adjustments

must take into account patient losses, organ function,

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

(continued from page 62)

Table 17

Advantages and Disadvantages of the Total Nutrient

Admixture (3-in-1) System

Advantages

• All components aseptically compounded by the pharmacy

• Preparation is more efficient for pharmacy personnel,

especially if automated

• Less manipulation of the system during administration

• Less risk of contamination during administration

• Less nursing time needed for 1 bag/d and no piggyback to

administer

• Less supply and equipment expense for only 1 pump and

IV tubing

• More convenient storage, fewer supplies, easier administration

in home care settings

• Glucose and venous access tolerance may be better in

some situations

• Possible applications in fluid-restricted patients

• May be more cost-effective overall in certain settings

Disadvantages

• Larger particle size of admixed lipid emulsion precludes use

of 0.22-micron (bacteria-eliminating) filter, and requires

larger pore size filter of 1.2 micron

• Admixed lipid emulsion less stable, more prone to separation

of lipid components

• Admixtures are more sensitive to destabilization with certain

electrolyte concentrations or the addition of iron

• Difficult to visualize precipitate or particulate material in

the opaque admixture

• Certain medications are incompatible with lipid emulsion

portion of admixture

• Catheter occlusion more common with daily lipid

administration

• Less attractive in pediatric settings due to pH and

compatibility considerations

Reprinted from Barber JR, Miller SJ, Sacks GS. Parenteral feeding

formulations. In: Gottschlich MM, Ed.

The Science and Practice of

Nutrition Support: A Case-Based Core Curriculum.

Dubuque, IA:

Kendall/Hunt Publishing Co.; 2001: 251–268 with permission from

the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.).

A.S.P.E.N. does not endorse the use of this material in any form

other than its entirety.

oral/enteral intake and the impact of medications.

Experience allows anticipation of trends and impact

on electrolyte manipulations. This is particularly

helpful when monitoring intervals are extended as

they are for home PN patients. Trends in serum elec-

trolyte levels are far more meaningful than looking

at a single value. Serum electrolyte levels fluctuate

under natural physiologic control and variance in

lab equipment. Minute adjustments in PN electrolytes

are rarely beneficial and often only warranted if the

patient has been on PN for a long enough time period

that response is well known. For a nice review/guide-

lines for electrolyte replacement, see references

44,67,68.

How Often Should Labs Be Checked?

Daily labs are needed when initiating PN. This fre-

quent level of monitoring may be warranted for several

days to >2 weeks while electrolytes are being adjusted

and the impact of PN initiation and advancement takes

place. Guidelines for appropriate lab monitoring are

addressed in Table 18.

Long-term Complications

Long-term complications of PN can include fatty liver,

cholestasis, metabolic bone disease, and electrolyte/

vitamin/mineral depletion or toxicity (46). In the long-

term PN patient, it is important to be aware of, and

monitor for, these adverse effects. This topic is beyond

the scope of this article, however, a nice review of long-

term complications is readily available (47). See Table

19 for gastrointestinal complications of long term PN.

What Should You Do When the Labs

on Your PN Patient Look Like This?!!

Lab Result @ 4:00 A.M.

Sodium 125

Potassium 6.7

Chloride 101

BUN 12

Creatinine 0.7

Glucose 896

Triglycerides 684

Magnesium 3.5

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 18

Suggested Monitoring for Parenteral Nutrition (In-patient)

Parameter Baseline Initiation Critically Ill Stable Patients

CBC with differential Yes Weekly Weekly

PT, PTT Yes Weekly Weekly

Basic chemistry—Na, K, Cl, CO

BUN, creatinine Yes Daily × 3 Daily 1–2 times per week

Magnesium, calcium, phosphorus Yes Day 1 As needed Weekly

Serum triglycerides Yes Day 1 As needed As needed

Serum glucose Yes Daily Daily 1–2 times per week

Capillary glucose Q 6 hrs × 48 hrs; As needed 3 x day until consistently As needed

stop if WNL <150 mg/dl*

Weight Yes Daily Daily 2–3 times per week

Intake and output Yes Daily Daily As needed

ALT, AST, ALP, total bilirubin Yes Day 1 Weekly Monthly

Nitrogen balance As needed As needed As needed

CBC = complete blood cell count; BUN = blood urea nitrogen; PT = prothrombin time; PTT = partial thromboplastin time; ALT = alanine aminotransferase;

AST = aspartate aminotransferase; ALP = alkaline phosphatase.

*More tightly controlled blood glucose levels of 80-130 may be sought (49).

Adapted from Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, Ed.

The Science and Practice of Nutrition Support: A Case-Based Core Curriculum.

Dubuque, IA: Kendall/Hunt Publishing Co.;2001: 211–223, with permission from the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). A.S.P.E.N.

does not endorse the use of this material in any form other than its entirety.

PRACTICAL GASTROENTEROLOGY • JULY 2006

A. Order insulin (20 units SQ) and sodium poly-

styrene resin (Kayexalate

) 30 mL enema STAT

B. Call the endocrine fellow

C. Check fingerstick glucose at the bedside NOW for

quick verification of chemistry result before giving

insulin

Note: This patient’s fingerstick glucose at 1800

and 2400 during PN infusion were 141 and 103

respectively.

The above situation demonstrates spurious lab results

after PN contamination of a blood sample drawn from

a central line without following proper flushing proce-

dure. The procedure includes turning off the PN, flush-

ing the line, discarding the initial aspirate, then draw-

ing up the sample amount needed for the lab and then

resuming the PN. If the PN admixture is not turned off

and/or if the flush is inadequate prior to the draw, the

lab results will reflect the extraordinarily high glucose,

potassium and triglyceride levels in the sample sec-

ondary to contamination with the PN solution. Other

electrolyte imbalances may also be seen. Although the

PN may be held upon reviewing these results, a quick

check of a bedside finger stick blood sugar and subse-

quent lab redraw is the most appropriate response.

CONCLUSION

PN is a valuable and necessary medical treatment for

many patients providing both nutritional sustenance

and life extension at a time when it is not possible to

sustain them any other way. By focusing on the essen-

tial elements of PN management, this form of nutrition

support can be applied successfully with minimal com-

plications, thus providing great benefit to those who at

one time would have been deemed “unfeedable.” See

Table 20 for summary guidelines.

■

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 19

Complications of Long Term PN (9,36)

Problem Possible Causes Symptoms Treatment/Prevention

Fatty Liver Exact etiology unknown. Theories include: Elevation of LFTs • Avoid overfeeding

Overfeeding of dextrose &/or total calories; • Do not exceed recommended

overfeeding of fat; EFAD; carnitine dosages of macronutrients

deficiency,choline deficiency (Table 3)

• Enteral nutrition as soon as

possible (even if trophic)

• Enteric antibiotics if blind loops/

bacterial overgrowth possible

• Add Taurine to PN

Cholestasis Exact etiology unknown. Theories include: Elevated alkaline phosphatase; • Avoid overfeeding

lack of nutrition in the bowel leading to progressive increase in • Do not exceed recommended

decreased bile stimulation and impaired total bilirubin dosages of macronutrients

bile flow; overfeeding of glucose, lipid (Table 3)

and/or amino acids; toxic tryptophan • Enteral nutrition as soon as

metabolites, choline deficiency possible

• Enteric antibiotics if blind loops/

bacterial overgrowth possible

Gastrointestinal Atrophy of villi in the GI tract due to lack Observed

in vitro

;

in vivo

only • Enteral/oral nutrition concurrent

Atrophy of enteral nutrients symptom may be enteric or as soon as possible

bacteremia and sepsis

without clear source

Gottschlich MM, Ed. Nutrition Support Dietetics Core Curriculum. 2nd edition. American Society of Parenteral and Enteral Nutrition. Silver Spring, MD: 1993.

Acknowledgment

Special thanks to Gordon Sacks for his editorial

review and comments.

Gordon S. Sacks, Pharm.D., BCNSP, FCCP

Clinical Associate Professor

Schools of Medicine and Pharmacy

University of Wisconsin–Madison

References

1. Lipman TO. The chicken soup paradigm. J Parenter Enteral

Nutr, 2003; 27:93-99.

2. Braunschweig CL, Levy P, Sheean PM, et al. Enteral compared

with parenteral nutrition: a meta- analysis. Am J Clin Nutr,

2001;74:534-542.

3. Perioperative total parenteral nutrition in surgical patients. The

Veterans Affairs Total Parenteral Nutrition Cooperative Study

Group. N Engl J Med, 1991;22;325(8):525-532.

4. Heyland DK, Dhaliwal R, Drover JW, et al. Canadian clinical

practice guidelines for nutrition support in mechanically venti-

lated, critically ill adult patients. J Parent Enteral Nutr,

2003;27(5):355-373.

5. American College of Chest Physicians Consensus Statement.

Chest, 1997;111(3):769-777.

6. National Advisory Group on Standards and Practice Guidelines

for Parenteral Nutrition. J Parent Enteral Nutr, 1998;22(2):49-66.

7. Krenitsky J. Adjusted body weight, pro: evidence to support the

use of adjusted body weight in calculating calorie requirements.

Nutr Clin Pract, 2005;20:468-473.

8. Frankenfield D. Energy and macrosubstrate requirements. In:

Gottschlich MM, Ed. The Science and Practice of Nutrition Sup-

port: A Case-based Core Curriculum. Dubuque, IA: Kendall/

Hunt Publishing Co.; 2001:36.

9. Von Allmen D, Fisher JF. Metabolic Complications. In: Fischer

JF (ed). Total Parenteral Nutrition. 2nd Ed. Boston, MA: Little

Brown Company; 1991.

10. Krzywda EA, Andris DA, Edmiston CE, et al. Parenteral Access

Devices. In: Gottschlich MM, Ed. The Science and Practice of

Nutrition Support: A Case-Based Core Curriculum. Dubuque,

IA: Kendall/Hunt Publishing Co.; 2001:230.

11. Jerome L, Cookson ST, McArthur MA, et al. Prospective evalu-

ation of risk factors for bloodstream infection in patients receiv-

ing home infusion therapy. Ann Inter Med, 1999; 131(5):340-347.

12. Infusion Nurses Society. Infusion Nursing Standards of Practice.

J Infusion Nursing, 2006;29(1S):75.

13. O’Grady NP, Alexander M, Dellinger EP, et al. Guidelines for the

prevention of intravascular catheter-related infections. MMWR,

2002;51(RR-10):1-29.

14. Mirtallo JM. Introduction to Parenteral Nutrition. In: Gottschlich

MM, Ed. The Science and Practice of Nutrition Support: A Case-

Based Core Curriculum. Dubuque, IA: Kendall/Hunt Publishing

Co.; 2001:217.

15. Adapted from information gathered from calculating osmolarity

of an IV admixture viewed 05/31/2006 on http://rxkinetics.com/

iv_osmolarity.html

16. Tighe MJ, Wong C, Martin IG, et. al. Do heparin, hydrocortisone,

and glyceryl trinitrate influence thrombophlebitis during full

intravenous nutrition via a peripheral vein? J Parent Enteral

Nutr, 1995;19(6):507-509.

17. Roongpisuthipong C, Puchaiwatananon O, Songchitsomboon S,

et al. Hydrocortisone, heparin, and peripheral intravenous infu-

sion. Nutrition, 1994;10(3):211-213.

18. Khawaja HT, Williams JD, Weaver PC. Transdermal glyceryl

trinitrate to allow peripheral total parenteral nutrition: a double-

blind placebo controlled feasibility study. J Royal Soc Med, 1991;

84:69-72.

19. Grimm H, Tibell A, Norrlind B, Blecher C, et al. Immunoregula-

tion by parenteral lipids: impact of the n-3 to n-6 fatty acid ratio.

J Parent Enteral Nutr, 1994;18(5):417-421.

20. Haber LM, Hawkins EP, Seilheimer DK, et al. Fat overload syn-

drome. An autopsy study with evaluation of the coagulopathy.

Am J Clin Pathol, 1988; 90(2):223-227.

21. Dahlstrom KA, Goulet OJ, Roberts RL, et al. Lipid tolerance in

children receiving long-term parenteral nutrition: a biochemical

and immunologic study. J Pediatr, 1988;113(6): 985-990.

22. Mirtallo J, Canada T, Johnson D, et al. Safe practices for par-

enteral nutrition. J Parent Enteral Nutr, 2004;28(6):S39-S70.

23. Wolfe RR, O’Donnell TF Jr, Stone MD, et al. Investigation of

factors determining optimal glucose infusion rate in total par-

enteral nutrition. Metabolism, 1980;29:892-900.

24. Frankenfield D. Energy and macrosubstrate requirements. In:

Gottschlich MM, Ed. The Science and Practice of Nutritional

Support: A Case Based Core-Curriculum. Dubuque, IA:

Kendall/Hunt Publishing Co.; 2001:234.

25. Macias WL, Alaka KJ, Murphy MH, et al. Impact of nutritional

regimen on protein catabolism and nitrogen balance in patients

with acute renal failure. J Parent Enteral Nutr, 1996;20:56-62.

26. Druml W. Nutritional management of acute renal failure. Am J

Kidney Dis, 2001; 37(1 Suppl 2):S89-S94.

27. Krenitsky J. Nutrition in Renal Failure: Myths and Management.

Pract Gastroenterol, 2004; 28(9):40.

PRACTICAL GASTROENTEROLOGY • JULY 2006

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

Table 20

Summary Guidelines

1. Determine if PN is truly indicated

2. Assess the patient (medical/surgical history, review

drug/medication profile, anthropometric data and lab

values)

3. Determine need for long-term vs. short term <7–10 days

IV access

4. Determine estimated kcal, protein and lipid needs

• 20–30 kcal/kg

• Protein 0.8–1.5 gm/kg

– Higher levels may be needed in severe catabolic

states

• Lipid to provide ≤30% of kcals

5. Determine initial electrolyte, vitamin and trace element

requirements; consider ongoing losses

6. Consider any additional additives to PN formulation

including insulin and H

-antagonists

7. Monitor for:

• Risk of refeeding syndrome

• Glucose intolerance

– If so initiate feeding at a low dextrose level and

advance cautiously as lab values are stable. If not

then attempt to advance to goal within the first

24-48 hours

8. Initiate trophic feedings or convert patient to PO or enteral

feeding when feasible

PRACTICAL GASTROENTEROLOGY • JULY 2006

28. Krenitsky J. Nutritional Guidelines for Patients with Hepatic Fail-

ure. Pract Gastroenterol, 2003; 27(6):23.

29. Van Way CW. Total calories vs nonprotein calories. Nutr Clin

Pract, 2001;16:271-272.

30. Miles JM, Klein J. Should protein calories be included in caloric

calculations for a TPN prescription? Point-counterpoint. Nutr

Clin Pract, 1996;11:204-206.

31. Devlin JW, Lau AK, Tanios MA. Propofol-associated hyper-

triglyceridemia and pancreatitis in the intensive care unit: an

analysis of frequency and risk factors. Pharmacother, 2005;

25(10):1348-1352.

32. MacLaren R, Wachsman BA, Swift DK, et al. Warfarin resis-

tance associated with intravenous lipid administration: discussion

of propofol and review of the literature. Pharmacotherapy, 1997;

17:1331-1337.

33. Chambrier C, Leclercq M, Saudin F, et al. Is vitamin K1 supple-

mentation necessary in long-term parenteral nutrition? J Parent

Enteral Nutr, 1998; 22:87-90.

34. Lennon C, Davidson KW, Sadowski JA, et al. The vitamin K con-

tent of intravenous lipid emulsions. J Parent Enteral Nutr, 1993;

17:142-144.

35. Duerksen DR, Papineau N. Prevalence of coagulation abnormal-

ities in hospitalized patients receiving lipid-based parenteral

nutrition. J Parent Enteral Nutr, 2004;28(1):30-33.

36. Matarese LE. Metabolic Complications of Parenteral Nutrition

Therapy. In: Gottschlich MM, Ed. The Science of Practice of

Nutrition Support: A Case-Based Core Curriculum. Dubuque,

IA: Kendall/Hunt Publishing Co.; 2001:275.

37. Faber MD, Schmidt RJ, Bear RA, et al. Management of fluid,

electrolyte, and acid-base disorders in surgical patients. In: Nar-

ins RG (ed). Clinical Disorders of Fluid and Electrolyte Metabo-

lism. 5th ed. New York: McGraw-Hill; 1987:1424.

38. Grant JP. Handbook of Total Parenteral Nutrition. 2nd ed. WB

Saunders; Philadelphia, PA; 1992:174.

39. Parenteral multivitamin products; drugs for human use; drug effi-

cacy study implementation; amended (21 CFR 5.70). Federal

40. Boosalis MG. Micronutrients. In: Gottschlich MM, Ed. The Sci-

ence and Practice of Nutritional Support: A Case Based Core-

Curriculum. Dubuque, IA: Kendall/Hunt Publishing Co. 2001:94.

41. Helphingstine CJ, Bistrian BR. New food and drug administra-

tion requirements for inclusion of vitamin K in adult parenteral

nutrition. J Parent Enteral Nutr, 2003; 27(3): 220-224.

42. Nutescu EA, Shapiro NL, Ibrahim S, et al. Warfarin and its inter-

actions with foods, herbs and other dietary supplements. Expert

Opin Drug Saf, 2006;5(3):433-451.

43. Safe Practices for Parenteral Nutrition Formulations. National

Advisory Group on Standards and Practice Guidelines for Par-

enteral Nutrition. J Parenter Enteral Nutr, 1998; 22(2);49-66.

44. Btaiche IF, Khalidi N. Metabolic complications of parenteral

nutrition in adults, part 2. Am J Health-Syst Pharm, 2004;61:

2050-2057.

45. Wardle CA, Forbes A, Roberts NB, et al. Hypermanganesemia in

long-term intravenous nutrition and chronic liver disease. J Par-

enter Enteral Nutr, 2004; 28:S39-S70.

46. Fessler TA. Trace Element Monitoring and Therapy For Adult

Patients Receiving Long Term Total Parenteral Nutrition. Pract

Gastroenterol, 2005;29(3):44.

47. Jeejeebhoy KN. Management of PN-induced Cholestasis. Pract

Gastroenterol, 2005; 29 (2):62.

48. Sacks G. Drug-nutrient considerations in patients receiving par-

enteral and enteral nutrition. Pract Gastroenterol, 2004;

28(7):39.

49. Van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin

therapy in critically ill patients. N Engl J Med,

2001;345:1359-

1367.

50. Rossetti L, Giaccari A, DeFronzo RA. Glucose toxicity. Diabetes

Care, 1990;13(6):610-630.

51. Frothingham R. Glucose homeostasis abnormalities associated

with use of gatifloxicin. Clin Infect Dis, 2005;41(9):1269-

1276.

52. Stausburg KM. Drug interactions in nutrition support. In:

McCabe JM, Frankel EH, Wolfe JJ, ed. Handbook of Food-Drug

Interactions. Boca Raton, Fl: CRC Press; 2003: 145-166.

53. Montoro JB, Pou L, Salvador P, et al. Stability of famotidine 20

and 40 mg/L in total nutrient admixtures. Am J Hosp Pharm,

1989;46(11):2329-2332.

54. Hatton J, Luer M, Hirsch J, et al. Histamine receptor antagonists

and lipid stability in total nutrient admixtures. J Parenter Enteral

Nutr, 1994;18(4):308-312.

55. Product information: Ranitidine package insert, Bedford Labora-

tories, May 20.

56. Khaodhiar L, Keane-Ellison M, Tawa NE, et al. Iron deficiency

anemia in patients receiving home total parenteral nutrition. J

Parenter Enteral Nutr, 2002;26:114-119.

57. Kwong KW, Tsallas G. Dilute iron dextran formulation for addi-

tion to parenteral nutrient solutions. Am J Hosp Pharm, 1980;

37(2):206-210.

58. Vaughan LM, Small C, Plunkett V. Incompatibility of iron dex-

tran and a total nutrient admixture. Am J Hop Pharm, 1990;

47:1745-1746.

59. Eisenberg PG, Gianino S, Clutter WE, et al. Abrupt discontinua-

tion of cycled parenteral nutrition is safe. Dis Colon Rectum,

1995; 38 (9):933-939.

60. Krzywda EA, Andris DA, Whipple JK, et al. Glucose response to

abrupt initiation and discontinuation of total parenteral nutrition.

J Parent Enteral Nutr, 1993;17:64-67.

61. Nirula R, Yamada K, Waxman K. The effect of abrupt cessation

of total parenteral nutrition on serum glucose: a randomized trial.

Am Surg, 2000;66(9):866-869.

62. McCray S, Walker S, Parrish CR. Much ado about refeeding.

Pract Gastroenterol, 2005; 23:26-44.

63. Plank LD, Connolly AB, Hill GL. Sequential changes in the

metabolic response in severely septic patients during the first 23

days after the onset of peritonitis. Ann Surg, 1998;228(2):146-

158.

64. Klein CJ, Stanek GS, Wiles CE. Overfeeding macronutrients to

critically ill adults: metabolic complications. J Am Diet Assoc,

1998;98(7):795-806.

65. Bu JA, Klish WJ, Walding WJ, et al. Energy metabolism, nitro-

gen balance, and substrate utilization in critically ill children. Am

J Clin Nutr, 2001;74(5):664-669.

66. McClave SA, McClain CJ, Snider HL. Should indirect Calorime-

try be used as a part of nutritional assessment? J Clin Gastroen-

terol, 2001;33(1):14-19.

67. Piazza-Barnett R, Matarese LE. Electrolyte management in total

parenteral nutrition. Support Line, 1999;21(2):8-15.

68. Kraft MD, Btaiche IF, Sacks GS, et al. Treatment of electrolyte

disorders in adult patients in the intensive care unit. Am J Health-

Syst Pharm, 2005;62:1663-1682.

NUTRITION ISSUES IN GASTROENTEROLOGY, SERIES #40

The Hitchhiker’s Guide to Parenteral Nutrition Management

VISIT OUR WEB SITE AT PRACTICALGASTRO.COM