Surgical Nutrition

Dr. Robert Mustard

September 28, 2010

Does it really matter?

• US VA TPN Study: NEJM: 325 p 525-532, 1991• 459 patients with (primarily) GI malignancies requiring

surgical resection• Patients stratified into 3 groups;

- normally nourished

- mild malnutrition

- severe malnutrition

Patients then randomized to 1-2 weeks preoperative TPN

vs control.

1991 VA Trial – Outcome (30 day)

Major infections complications N Mild Severe• TPN 12.2 15.2

12.9

• Control 4.0 6.6 10.5

Major non-infections complications• TPN 14.3 16.1

22.6

• Control 16.0 27.6 42.1

*

No difference in mortality

(Editorial by A. Detsky)

Why might TPN be bad for your patients?

• 1) Central line

• 2) hyperglycemia

• 3) gut atrophy

• 4) IV lipids

• 5) Query hepatic cholestasis

Further evidence that TPN may be bad for your patients

• M.J. Sena, et al: Early Supplemental Parenteral Nutrition is Associated with Increased Infectious Complications of Critically Ill Trauma Patients;

• JACS 207: p 459-467, 2008

Determining Nutritional Status

• J.P. Baker, et al: Nutritional Assessment: A Comparison of Clinical Judgment and Objective Measurements.

NEJM: 306, p 969-972, 1982.

• A.S. Detsky, et al: What is Subjective Global Assessment of Nutritional Status?

J. Parent. Ent. Nutrition 11: p 8-13, 1987.

Subjective Global Assessment of Nutritional Status

History:

1) Weight change

2) Dietary intake change

3) GI symptoms

4) Functional capacity

5) Underlying disease (+ metabolic demand)

Physical Examination:

1) Lossness of subcutaneous fat

2) Muscle wasting

3) Ankle edema

4) sacral edema

5) ascites

Subjective Global Assessment of Nutritional Status

Hx + P/E → Well nourished

Moderately malnourished Severely malnourished

No explicit numerical weighting scheme

Who Needs Nutritional Support?

1) Normally nourished or moderately malnourished:

7-10 days NPO well tolerated

2) Severely malnourished: Start feeds ASAP

Consider patients underlying disease and the likelihood of rapid recovery following treatment (eg – surgical excision of cancer)

How Much Food Is Needed?

Enough to avoid complications caused by malnutrition.

Guidelines:

1) Calories - estimate BME from Harris-Benedict formula (sex, age, weight, height)- ~ 25 Kcal/kgm/24h- estimate ”stress factor” ~ 25% for general surgical patients as much as 100% for major burn patients

2) Protein- basal requirements ~ 0.7 gm/kgm/24h- with stress factor ~ 1 gm/kg/24hr

3) Lipids

- used to supplement glucose calories- at least 500 mls/week required for metabolic purposes

4) Electrolytes- trace elements- vitamins- same for all

What Route to Use

Enteral, if at all possible

IGNORE - recent GI surgery

- presence or absence of bowel sounds,

flatus, etc

DO NOT IGNORE - Olgilves Syndrome

- constipation

- diarrhea

Parenteral Routes

- PVC line

- PICC line

- Hickman catheter

- Porta-cath

Enteral Routes

- NG tube (regular or silastic)

- NJ tube

- surgical G or J – tube

- percutaneous G or J – tube

- endoscopic G – tube

Notes

1) Risk of aspiration pneumonia more or less independent of feeding mechanism

2) Always check gastric residuals with G-tube feeds

3) Beware of complications of J-tube feeds (small bowel necrosis)

4) All tubes are mobile!

Case Studies

1) Patient with severe closed head injury. Tracheostomy in place, need for long term

feeds- ? Route.

2) Post-op patient who suffered from bowel infarction and is left with 3 feet of small bowel, and a left colon. ? How to feed.

3) Patient in ICU on ventilator with severe acute pancreatitis. ? How to feed.

4) Patient with Crohn’s disease, severe weight loss, and high grade small bowel obstruction. ? How to feed.