SURGICAL NUTRITION
Crissa Marie D. Pineda
ESTIMATION OF ENERGY REQUIREMENTS
Overall nutritional assessment
 To determine severity of nutrient deficiencies or excess
 To aid in predicting nutritional requirements
 Presence of weight loss, chronic illnesses, dietary habits, social habits,
medications
Goal: To meet the energy requirements for essential metabolic
processes and tissue repair
ESTIMATION OF ENERGY REQUIREMENTS
HARRIS-BENEDICT EQUATIONS
Men = 66.47 + 13.75 (Wt in kg) + 5.0 (Ht in cm) – 6.76 (Age in years)
kcal/d
Women= 655.1 + 9.56 (Wt in kg) + 1.85 (Ht in cm) - 4.68 (Age in years)
kcal/d
30 kcal/kg per day meets energy requirements in most postsurgical patient
with a low risk of overfeeding
ESTIMATION OF ENERGY REQUIREMENTS
Goal: To meet the substrate requirements for protein synthesis
Non-protein calorie : Nitrogen Ratio of 150 : 1 should be
maintained
0.25-0.35 g of Nitrogen per kilogram of body weight should be
provided daily
VITAMINS AND MINERALS
Not given in the absence of pre-operative deficiencies
Commercial enteral diets contain varying amounts of essential
vitamins and minerals
OVERFEEDING
Results from overestimation of
caloric needs
 Actual body weight used in calculating
BEE in critically ill patients with fluid
overload or obese patients
 Indirect calorimetry overstimates BEE by
10%-15% in stressed patients
(ventilatory support)
Contributes to clinical deterioration
via
 Increased oxygen consumption
 Increased carbon dioxide production
 Prolonged need for ventilatory support
 Fatty liver
 Suppression of leukocyte function
 Hyperglycemia
Dry weight should be obtained from  Increased risk of infection
previous records or relatives
ENTERAL NUTRITION
ENTERAL NUTRITION
Preferred over parenteral nutrition
 Lower cost
 Complications of IV route complications
 Consequences of gastrointestinal tract disuse
Post-operative enteral vs. parenteral nutrition in patients
undergoing GI surgery
 Reduced infectious complications
 Reduced acute-phase protein production
ENTERAL NUTRITION
In patients with severe abdominal or thoracic trauma
 Significant reduction in infectious complications vs unfed or received parenteral nutrition
In critically ill patients
 Early enteral nutrition associated with better small intestinal carbohydrate
absorption
 Early enteral feeding is a recommended standard of care
In patients with closed-head injury
 No significant differences in outcome
 Frequently associated with underfeeding and calorie deficiency
INITIATION OF ENTERAL NUTRITION
Immediately after adequate resuscitation (adequate urine output)
Presence of bowel sounds, flatus or stool are not absolute
prerequisites
In patients who underwent bowel resection
 No evidence to support in withholding enteric feeding
 Reduced fistula formation
HYPOCALORIC ENTERAL NUTRITION
Critically ill or injured patients
 25-30 kcal/kg- to meet the patient’s energy needs, to avoid loss of lean
body mass
ENTERAL FORMULAS
Must be:
1. Gastrointestinal tolerance-promoting
2. Anti-inflammatory
3. Immune-modulating
4. Organ supportive
5. Standard enteral nutrition
ENTERAL FORMULAS
Functional status of GIT determines the type of enteral
solutions to be used
Intact GIT: Complex solutions
Difficulty tolerating standard enteral formulas: Peptide- and MCTbased formulas with prebiotics
Malabsorption issues: Hydrolyzed protein formulas
IMMUNONUTRIENTS
Provision of immune-modulating nutrients to support immune
response and to lower infectious risk
 Glutamine
 75% found in skeletal muscle
 Major fuel source for enterocytes, lymphocytes, and macrophages
 During sepsis or in tumor-bearing hosts, glutamine stores are shunted toward
the visceral organ and tumors  glutamine-depleted environment 
enterocyte and immunocyte starvation
IMMUNONUTRIENTS
 Arginine
Net nitrogen retention and protein synthesis
𝞈-3 PUFAs (canola oil or fish oil)
Reduces proinflammatory response from prostaglandin production
LOW-RESIDUE ISOTONIC FORMULAS
Provide a caloric density of 1.0kcal/ml
Provide baseline carbohydrates, protein, electrolytes, water, fat
and fat-soluble vitamins
Contain no fiber bulk; leaves minimum residue
First-line formula for stable patients with intact GIT
ISOTONIC FORMULAS WITH FIBER
Soy-based
Delay intestinal transit time and reduces diarrhea
IMMUNE-ENHANCING FORMULAS
Glutamine, arginine, 𝞈-3 fatty acids, nucleotides
CALORIE-DENSE FORMULAS
Greater caloric value for the same volume
1.5-2 kcal/ml
For patients requiring fluid restriction or unable to tolerate largevolume infusions
Suitable for intragastric feedings
HIGH-PROTEIN FORMULAS
Nonprotein-calorie:nitrogen ratio between 80:1 and 120:1
Limited data in trials about dose of protein in critically ill patients
ELEMENTAL FORMULAS
Contain predigested nutrients and peptides
Complex carbohydrates and fat content are limited
Advantage: ease of absorption
However, scarcity of fat, vitamins and trace elements limits is longterm use
Used in patients with malabsorption, gut impairment, pancreatitis
No benefit in routine use
RENAL FAILURE FORMULAS
Primary benefit:
 Lower fluid volume
 Lower concentration of K, P, Mg
Does not contain trace elements or vitamins
PULMONARY FAILURE FORMULAS
Fat content increased to 50% of total calories
Reduced carbohydrate content
Goal: To reduce CO2 production and alleviate ventilation burden
HEPATIC FAILURE FORMULAS
Goal: To reduce aromatic amino acid levels and increase levels of
branched-chain amino acids
No clear benefits proven
ACCESS FOR ENTERAL NUTRITION
PARENTERAL NUTRITION
PARENTERAL NUTRITION
Continuous infusion of hyperosmolar solution through an indwelling
catheter inserted into the SVC
Calorie:Protein ratio must be adequate
 100-150 kcal/g nitrogen
Both carbohydrates and proteins must be infused simultaneously
Short-term use in critically-ill patients
•
Higher rates of infectious complications
PARENTERAL NUTRITION
RATIONALE FOR PARENTERAL NUTRITION
Principal indications for parenteral nutrition:
 Malnutrition, sepsis, or surgical/traumatic injury in seriously ill patients for
whom use of GIT for feedings is not possible
Can rapidly improve nitrogen balance  enhances immune
function
Routine postoperative use of parenteral nutrition
 No clinical benefit
 Increase in complication rate
PATIENT GROUPS FOR PARENTERAL NUTRITION
Newborn infants with catastrophic gastrointestinal anomalies, such as
tracheoesophageal fistula, gastroschisis, omphalocele, or massive intestinal
atresia
Infants who fail to thrive due to gastrointestinal insufficiency associated with
short-bowel syndrome, malabsorption, enzyme deficiency, meconium ileus, or
idiopathic diarrhea
Adult patients with short-bowel syndrome secondary to massive small-bowel
resection (<100 cm without colon or ileocecal valve or <50 cm with intact
ileocecal valve and colon)
PATIENT GROUPS FOR PARENTERAL NUTRITION
Patients with enteroenteric, enterocolic, enterovesical, or high-output
enterocutaneous fistulas (>500 mL/d)
Surgical patients with prolonged paralytic ileus aftermajor operations (>7 to
10 days), multiple injuries, or blunt or open abdominal trauma, or patients with
reflex ileus complicating various medical diseases
Patients with normal bowel length but with malabsorption secondary to sprue,
hypoproteinemia, enzyme or pancreatic insufficiency, regional enteritis, or
ulcerative colitis
Adult patients with functional gastrointestinal disor- ders such as esophageal
dyskinesia after cerebrovascular accident, idiopathic diarrhea, psychogenic
vomiting, or anorexia nervosa
PATIENT GROUPS FOR PARENTERAL NUTRITION
Patients with granulomatous colitis, ulcerative colitis, or tuberculous enteritis in
whom major portions of the absorp- tive mucosa are diseased
Patients with malignancy, with or without cachexia, in whom malnutrition might
jeopardize successful use of a therapeutic option
Patients in whom attempts to provide adequate calories by enteral tube
feedings or high residuals have failed
Critically ill patients who are hypermetabolic for >5 days or for whom
enteral nutrition is not feasible
CONTRAINDICATIONS TO PARENTERAL NUTRITION
Patients for whom a specific goal for patient management is lacking or for
whom, instead of extending a meaningful life, inevitable dying would be
delayed
Patients experiencing hemodynamic instability or severe metabolic
derangement (e.g., severe hyperglycemia, azotemia, encephalopathy,
hyperosmolality, and fluid-electrolyte disturbances) requiring control or
correction before hyper- tonic intravenous feeding is attempted
Patients for whom gastrointestinal tract feeding is feasible; in the vast
majority of instances, this is the best route by which to provide nutrition
CONTRAINDICATIONS TO PARENTERAL NUTRITION
Patients with good nutritional status
Infants with <8 cm of small bowel, because virtually all have been unable to
adapt sufficiently despite prolonged periods of parenteral nutrition
Patients who are irreversibly decerebrate or otherwise dehumanized
TOTAL PARENTERAL NUTRITION
PERIPHERAL PARENTERAL NUTRITION
Low osmolality solution
 Reduced levels of dextrose (5-10%) and protein (3%)
 Allows administration via peripheral veins
 Not appropriate for repleting patients with severe malnutrition
Used for short periods (<2 weeks)
INITIATION OF PARENTERAL NUTRITION
COMPLICATIONS OF PARENTERAL NUTRITION
Sepsis
 Contamination of central venous catheter (Central line-associated
bloodstream infections)
Earliest sign: glucose intolerance (with or without temperature
increase)
Catheter should be removed and submitted for culture
If infection persists without a definable source, catheter should be
placed into opposite subclavian vein or into one of the internal
jugular vein
COMPLICATIONS OF PARENTERAL NUTRITION
Rate of catheter infection: femoral vein > jugular vein > subclavian vein
Others:
Pneumothorax
Hemothorax
Hydrothorax
Subclavian artery injury
Thoracic duct injury
Cardiac arrythmia
Air embolism
Catheter embolism
Cardiac perforation with tamponade
COMPLICATIONS OF PARENTERAL NUTRITION
Metabolic complications
1.
2.
3.
4.
5.
Hyperglycemia
Carbon dioxide retention
Respiratory insufficiency
Hepatic steatosis
Cholestasis  formation of gallstones
COMPLICATIONS OF PARENTERAL NUTRITION
Intestinal atrophy
 Intestinal mucosal therapy
 Diminished villous height
 Bacterial overgrowth
 Reduced lymphoid tissue size
 Reduced IgA production
 Impaired gut motility