nutrition in surgery

Nutrition in Surgery

Name: Nurzawani Binti ShamsudinMatric No: 0918424

OUTLINE OF THE SEMINAR

• Definition • Causes of inadequate intake• Nutritional status, assessment, &

support

Introduction

• Introduction • Indications• Composition• Complications

Enteral nutrition

•Introduction •Indications•Composition•Complications

Parenteral nutrition

INTRODUCTION

1. Definition of nutrition & malnutrition

2. Causes of malnutrition

3. Objectives of nutritional support

4. Assessment of nutritional status

5. Estimating energy requirement

6. Estimating nutritional requirement.

NUTRITION

DefinitionThe taking in and metabolism of nutrients (food and other nourishing material) by an organism so that life is maintained and growth can take place.

Dorland’s Pocket Medical Dictionary

MALNUTRITION

Definition

A disorder of nutrition or a wasting condition resulting from energy and protein deficiency, sometimes with vitamin and trace element deficiency as well.

Dorland’s Pocket Medical Dictionary

MalnutritionCauses

◦Reduced food intake anorexia fasting pain on swallowing, physical or mental

impairment

◦Malabsorption impaired digestion or

absorption excess loss from gut

◦Altered metabolism trauma burns sepsis surgery cancer cachexia

IMPORTANCE OF NUTRITION IN SURGERY

1. Surgical procedures (and subsequent fasting) after admission can cause these patients to go into severe malnutrition quickly, often before the treating team realizes it.

2. There is evidence that patient with severe protein depletion have greater incidence of postoperative complication such pneumonia, wound infection, & prolonged hospital stay.

Disease/surgery

Neuroendocrine stress responsePro-inflammatory cytokine response

Metabolic change or/and reduced food intake

Protein and energy loss

Slow recovery, poor wound healing, and Increased infection

CAUSES OF INADEQUATE INTAKE

Not appetiz

ing food

weak and

anorexic

patientincreased

metabolic

demand

GI obstruc

tion

Cumulative

effects of

repeated

periods of

fasting

Intestinal

failure

OBJECTIVE OF NUTRITIONAL SUPPORT

•Provide nutrition support consistent with patient’s medical condition

•Prevent/ treat macronutrient and micronutrient deficiency

•Provide doses of nutrient compatible with existing metabolism

•Avoid/ manage complications related to the technique of nutrient delivery.

•Improve patient’s outcome such as those related to morbidity

•To prevent and minimize the effect of catabolism

ASSESSMENT OF NUTRITIONAL STATUS

Nutritional assessment

Depleted reserves

Muscle wasting, loss

of subcutaneous fat, albumin < 30 g/L, weight loss 10-15%.

Poor current intake

Anorexia/vomiting, poor intake on food

chart

NUTRITIONAL

SUPPORT

Likely clinical courseIf not going to eat within

next 5 days, if already

malnourish and at risk of further major complication

such as abscess/fistul

a

ASSESSMENT OF NUTRITIONAL STATUS

1. History

2. Diet assessment.

3. Physical Examination.

4. Investigation

ASSESSING PATIENT FOR MALNUTRITION1. Clinical assessment: Lack of nutritional intake for 5 days or more. Clinical appearance – does the patient

looked malnourished? Unintentional weight loss for more than

10% from usual body weight for previous 6 months. More than 20% is likely to represent severe malnutrition.

BMI less than 18.5. History of poor nutrient intake: anorexia,

nausea, vomiting, early satiety and food preference.

• Clinical nutritional history based on understanding of the etiologies and pathophysiology of malnutrition.

• History of poor nutrient intake • Anorexia • Nausea• Vomiting• Early satiety• Food preference

• Loss of body weight (see table)• Weight loss of more than 10-15% during the

past 6 months

EVALUATION OF MALNUTRITION (HISTORY)

Percentage of weight loss and impression

% weight loss Impression5 Normal 10 -15 Risk15 – 20 Malnutrition20 – 30 Severe malnutrition30 - 40 Incompatible

Social & economic condition that may lead to poverty & malnutrition◦ Inadequate income◦ Homeless◦ Drug abuse◦ Chronic alcoholism

Gastrointestinal symptoms◦ Dysphagia◦ Recurrent vomiting◦ Chronic diarrhea◦ Food intolerance

Other chronic medical illnesses◦ Disseminated cancer◦ COPD◦ Chronic inflammatory disease

EVALUATION OF MALNUTRITION (HISTORY)

EVALUATION OF MALNUTRITION (PHYSICAL EXAMINATION)Findings Interpretation

General appearance Weight loss

Decreased temporal & proximal extremity muscle mass

Decreased “pinch test”

Malnutrition < 90% of ideal weight

Decreased skeletal protein

Decreased body fat stores

Skin, nails, hairEasily plucked hair

Spooning of nails

Protein

Iron

Findings InterpretationSkin, nails, hairEasy bruising, perifollicular hemorrhage

“Flaky paint” of the lower extremity

Coarse skin, papular keratitis “goose bumps”

Peripheral edema

Vitamin C

Zink

Vitamin A

Protein

EyesConjunctival pallor

Bitot spot

Opthalmoplegia

Anemia (non-specific)

Vitamin A

Thiamine

Papular keratitis

Bitot spot

Perifollicular hemorrhage

Nasolabial seborrhea

Flaky paint of lower limb

PHYSICAL EXAMINATION ANTHROPOMETRY

Definition

• The science dealing with measurement of the size, weight and proportions of human body

• It can assess level of energy reserves by estimate amount of subcutaneous adipose stores.

• However it cannot identify specific nutrient deficiency

Anthropometric assessment: Triceps skin fold thickness (mm)

Mid arm circumference (cm) :

Mid-upper circumference (cm) – (π x triceps skin fold thickness) (cm)

% standard men women interpretation

100 12.5 16.5 Adequate

50 6 8 Borderline

20 2.5 3 Severe

% standard men women interpretation

100 25.5 23 Adequate

80 20 18.5 Borderline

60 15 14 Depletion

40 10 9 Severe

Body Mass Index

EVALUATION OF MALNUTRITION (LABORATORY INVESTIGATION)

To detect subclinical nutritional deficiencies in patients

• Nitrogen Balance• Serum Albumin• Creatinine excretion • Immunological Function

assessment

Nitrogen balance

◦ Nitrogen balance provides an index of protein gain or loss:

6.25 protein gained is equivalent to 1 g nitrogen

◦ Can be assessed by measuring the difference between nitrogen consumed (mouth, enteral tube or IV) and nitrogen excreted in the urine, feces and other intestinal sources.

◦ In most cases, total urine nitrogen can be calculated by dividing 24-h urinary urea nitrogen by 0.85 & assuming approximately 2g/d for nitrogen losses in feces & sweat.

Blood indices:

Nitrogen Intake – loss [90% urine, stool 5%, integument 5%]

or[Protein intake (g)/6.25] – urinary urea (g) – 2(for stool & skin) – 2(non-urea nitrogen)

Serum Albumin

◦ Serum albumin level falls during the acute stress of surgery, sepsis or other acute inflammatory illness because of increased circulating extravascular volume

TNF-α mediated inhibition of albumin synthesis

◦ The measurement of serum proteins, in particular albumin, is often used as an index of malnutrition (<35g/L)

◦ Sensitive but non-specific.

◦ The half-life of albumin is 14 to 18 days.

◦ Prealbumin (half-life, 3 to 5 days) or transferrin (<200 mg/dL; half-life, 7 days), have been proposed as more sensitive indicators of rapid changes in nutritional status.

Blood indices

Creatinine Excretion

◦ Creatinine is a metabolic product of skeletal muscle creatine.

◦ It is produced constantly in an amount directly proportional to skeletal muscle mass.

◦ With steady state a day-to-day renal function, each gram of creatinine in the 24-h urine collection represents 18.5g of fat free skeletal muscle.

◦ Measurement of creatinine in 24-h urine collection can be used as a relative measure of this body compartment.

Blood indices

Immunological assessment

◦ Delayed cutaneous hypersensitivity or anergy, most commonly tested by delayed reaction to skin recall antigens, was widely used in early studies of nutritional assessment and is a manifestation of cell-mediated immunity

◦ Total Lymphocyte count is often <1000 /μL in PCM and may accompany anergy to common skin test antigens.

◦ However, not all malnourished patients are at risk and the defect is immunologic, not nutritional.

Blood indices

Adverse effect of protein or calories depletion

Impaired wound healing and higher rate of wound breakdown.

Impaired immune function and the ability to against infection.

Skeletal muscle mass is lost, reducing muscular strength and general physical activity as well as causing fatigue.

Thoracic muscle mass depletion depresses respiratory efficiency and increase risk of pneumonia.

Albumin becomes depleted leading to generalized edema.

Adverse effect cont.

Small bowel mucosa atrophy reduces its ability to absorb nutrient and may lead to bacterial translocation into bloodstream because loss of mucosal integrity.

Impaired mental function leads to apathy, depression and low morale.

Post operative complication rates are higher. Prolonged recovery times and longer hospital stay.

ASSESSMENT OF NUTRITIONAL REQUIREMENT

Energy and protein requirement vary depending on weight, body composition, clinical status, mobility and dietary intake.

Few patients require more than 2500 kcal/day. Additional calories are unlikely to be used effectively and may constitute a metabolic stress.

Refeeding the chronically starved patient must be cautious because of the dangers of hypokalemia and hypophosphatem.ia

uncomplicated Complicated/stressed

Energy (kcal/kg/day)

25 30 – 35

Protein (g/kg/day) 1.0 1.3 – 1.5

REFERENCESGarden’s Principles & Practice of

Surgery, 5th edition.Burkitt’s Essential Surgery, 4th

edition.Medical Nutrition Therapy

Guidelines for nutrition support in critically ill adult by Ministry of Health, Malaysia

Metabolic Response to StarvationAfter 12 hours of not feeding

Plasma insulin level falls Glucagon rises Hepatic glycogen is gradually converted into

glucose With prolong starvation, muscle glycogen is

broken down and converted into lactate which is taken to the liver and converted to glucose

After 24 hours Hepatic gluconeogenesis from amino acids

precursors start with loss of about 75g of skeletal muslce protein per day.

Metabolisms in starvation and stressed state

MuscleProtein

75g

Fat storesTryglicerides

Amino acid

Glycerol

Fatty acid

LiverGlycogen

75ggluconeogenesis

Oxidation

Fatty acid

Glucose180g

brain

RBCWBC

NeuronsKidneymuscle

Lactate +pyruvate

Ketone HeartKidneysmuscle

Fig :Metabolism during fasting (<5 days)

MuscleProtein250g

Fat storesTryglicerides

Amino acid

Glycerol

Fatty acid

KIDNEYgluconeogenesis

Gluconeogenesis

LIVERoxidation

Fatty acid

Glucose360g

Wound

RBCWBCNerveMuscleKidney

Lactate+pyruvate

Ketone

HeartKidneyMuscle Fig: Fuel utilization following trauma

In Acute injury, significant alteration in substrate utilization. There is enhanced

nitrogen loss indicative of protein catabolism.

ENERGY REQUIREMENToBEE (men) = 66.47 + 13.75 (weight) + 5.0 (height) – 6.76 (age) x (activity factor) x (injury factor) kcal/dayoBEE (women) = 655.1 + 9.56 (weight) + 1.85 (height) – 4.68 (age) x (activity factor) x (injury factor) kcal/day

BEE = Basal Energy Expenditure = quantity of energy required to satisfy the requirements of the body at rest

oEquation adjusted for type of surgical stress

oSuitable for estimating energy requirement in >80% of patients

oProvision of 30kcal/kg/day will adequately meet energy requirement ( reduce risk of overfeeding)

oActivity factor伉 confined to bed :1.2伉 out of bed :1.3

oInjury Factor伉 minor operation :1.20 伉 skeletal trauma :1.35伉 Major sepsis :1.60伉 severe thermal burn :1.5

•Estimation of energy and protein requirement:

Uncomplicated Complicated

Energy 30 34 – 40(kcal/kg/day)Protein 1.0 1.3 – 2(g/kg/day)

•24-hour urinary urea excretion• Common method for assessing protein

requirement