Nutritional Care of the Bariatric Nutritional Care of the Bariatric Patient in Critical CarePatient in Critical Care

Christine WardChristine WardBariatric DietitianBariatric DietitianSeptember 2011September 2011

Aim Aim

To identify factors that may impact on the To identify factors that may impact on the nutritional care of the bariatric patient groupnutritional care of the bariatric patient group

Why this group may require a Critical Care Why this group may require a Critical Care admission?admission?

What are the potential issues regarding What are the potential issues regarding feeding?feeding?

Which BMR estimation equation is most Which BMR estimation equation is most appropriate for the bariatric patient?appropriate for the bariatric patient?

Factors that may impact on nutritional Factors that may impact on nutritional care of bariatric patientscare of bariatric patients

Obese patients generally viewed as over nourishedObese patients generally viewed as over nourished Potentially deficient in a number of nutrientsPotentially deficient in a number of nutrients Respond to injury differently; can not utilise/mobilise Respond to injury differently; can not utilise/mobilise

fat stores for energy as well as lean counterpartsfat stores for energy as well as lean counterparts Will draw on lean mass for energy Will draw on lean mass for energy Considered that they may already metabolically Considered that they may already metabolically

stressed due to obesitystressed due to obesity 2 weeks Pre-operative dietary restriction 2 weeks Pre-operative dietary restriction

~1000kcal/day~1000kcal/day

The bariatric candidate over nourished or not?The bariatric candidate over nourished or not?

04/18/23 4

Vitamin/mineral ERI %

Ernst et al 2009 %

Folate 40 3.4Folate & B12 15 18.1Iron 40 n/aZinc 50 24.625 OH Vit D 40 25.4Vit D & Secondary hyperparathyroidism

50 36.6

Type of SurgeryType of Surgery

Laparoscopic ProceduresLaparoscopic Procedures

RestrictiveRestrictive• Adjustable Gastric BandAdjustable Gastric Band• Sleeve GastrectomySleeve Gastrectomy

Restrictive and MalabsorptiveRestrictive and Malabsorptive• Roux-en-Y-Gastric BypassRoux-en-Y-Gastric Bypass• Duodenal Switch /BPDDuodenal Switch /BPD

Critical care admission?Critical care admission?

• Planned Critical CarePlanned Critical Care•Clotting issues thrombolysis•CPAP: patient not independent

Unplanned Bariatric patients in Unplanned Bariatric patients in Critical CareCritical Care

•Undiagnosed sleep apnoeaUndiagnosed sleep apnoea•Prolonged ventilationProlonged ventilation•Large bleeds - liverLarge bleeds - liver•Conversion to open procedureConversion to open procedure•Rhabdomyolysis, renal failure, sepsis, Rhabdomyolysis, renal failure, sepsis,

respiratory failurerespiratory failure•Anastomotic leak or strictureAnastomotic leak or stricture

ERI: 5% patients (6-20% cited in many papers)ERI: 5% patients (6-20% cited in many papers)

Usual Protocol post surgeryOral Route

Immediately post bariatric surgery if gut intactImmediately post bariatric surgery if gut intact• day 1; sips, day 1; sips, • day 2; clear fluid, day 2; clear fluid, • day 3; free fluidday 3; free fluid

Use of nutritional supplements, high protein Use of nutritional supplements, high protein where appropriate where appropriate

Feeding Route?Feeding Route?

Enteral or Parenteral NutritionEnteral or Parenteral Nutrition ? NG, NJ , gastrostomy / jejunostomy ? NG, NJ , gastrostomy / jejunostomy

• Altered gastrointestinal anatomy/functionAltered gastrointestinal anatomy/function• Which feed?Which feed?

TPN TPN How soon? How soon?

• ?Within 48 hours or ? NICE 2006?Within 48 hours or ? NICE 2006• Re-feeding issues K, Mg, PO, thiaminRe-feeding issues K, Mg, PO, thiamin• Biochemistry monitoring (daily or as local protocol)Biochemistry monitoring (daily or as local protocol)• Is it possible to meet nutritional requirements?Is it possible to meet nutritional requirements?

Overfeeding vs. under feedingOverfeeding vs. under feeding

Risks from nutritional support for the Risks from nutritional support for the obese patientobese patient

Overfeeding Overfeeding Increase C0Increase C022 , breathing and prolonged , breathing and prolonged

mechanical ventilationmechanical ventilation Promotes fat infiltration of liver (esp. CHO)Promotes fat infiltration of liver (esp. CHO) Cautious administration of CHO (dextrose) fat and Cautious administration of CHO (dextrose) fat and

fluid for obese with T2DM, Congestive heart fluid for obese with T2DM, Congestive heart failure, metabolic syndrome (exacerbation of failure, metabolic syndrome (exacerbation of conditions)conditions)

Hypo energetic feeding and protein Hypo energetic feeding and protein sparingsparing

Improved glucose controlImproved glucose control Improved serum iron binding and albuminImproved serum iron binding and albumin Appropriate energy deficit without increasing Appropriate energy deficit without increasing

lean tissue catabolism can be achievedlean tissue catabolism can be achieved Dickerson et al 2004, Choban et al 2005, 1997 50% Dickerson et al 2004, Choban et al 2005, 1997 50%

of energy requirements and 2.1g protein /kg IBW of energy requirements and 2.1g protein /kg IBW resulted in N balanceresulted in N balance

Aim of nutritional support in critically Aim of nutritional support in critically ill patients?ill patients?

Meeting measured energy requirements Meeting measured energy requirements vs. preservation of lean body mass vs. vs. preservation of lean body mass vs. risks of under or overfeedingrisks of under or overfeeding

BMR Prediction Equations (Schofield) BMR Prediction Equations (Schofield)

Criticism of current PENG guidance Criticism of current PENG guidance Estimations equations based on healthy Estimations equations based on healthy

populationpopulation Inappropriate use of stress factors; overestimates Inappropriate use of stress factors; overestimates Use of static variable such as weight, the body’s Use of static variable such as weight, the body’s

physiology ?temperature and respiration rate physiology ?temperature and respiration rate Based on a linear relationship between weight Based on a linear relationship between weight

and BMRand BMR

HoweverHowever Findings from Horgan and Stubs 2003 re-Findings from Horgan and Stubs 2003 re-

examination of Schofield equation:examination of Schofield equation: Small numbers of obese patientsSmall numbers of obese patients

• BMI>30 =4.5%BMI>30 =4.5%• The linear relationship between BMR, weight, height The linear relationship between BMR, weight, height

and age only evident to a weight of ~ 70-75kgand age only evident to a weight of ~ 70-75kg

BMR Prediction EquationsBMR Prediction Equations

Over estimates requirements for high BMIOver estimates requirements for high BMI Adipose tissue to lean tissue relationship 75:25Adipose tissue to lean tissue relationship 75:25 Main determinant of BMR is lean tissueMain determinant of BMR is lean tissue

Obese have a higher absolute BMR due to a Obese have a higher absolute BMR due to a greater total mass of metabolically active tissuegreater total mass of metabolically active tissue

BMR /Kg is lower due to the higher proportion of BMR /Kg is lower due to the higher proportion of adipose tissueadipose tissue

BMR/Kg of fat free mass for most subjects is the BMR/Kg of fat free mass for most subjects is the samesame

Henry/Oxford Equations 2005Henry/Oxford Equations 2005

Based on studies from 1914-2005Based on studies from 1914-2005 10,552 BMR values10,552 BMR values Rigorous evaluation of methodologyRigorous evaluation of methodology

Advantages Advantages Contains a more representative sample of the Contains a more representative sample of the

world populationworld population

SACN recommendations (draft)SACN recommendations (draft)(www.sacn.gov.uk)(www.sacn.gov.uk)

Use of Henry BMR equations Use of Henry BMR equations Weight onlyWeight only Height and weightHeight and weight Henry found no significant advantage in ht & wt Henry found no significant advantage in ht & wt

equationequation For predicting BMR using weight onlyFor predicting BMR using weight only

(height difficult to obtain in clinical setting)(height difficult to obtain in clinical setting) Launch later this yearLaunch later this year

Assessment prior to feedingAssessment prior to feeding As you would for other obese or lean individualAs you would for other obese or lean individual• Up to date weight crucial Up to date weight crucial

• Scales suitable for purpose, bed, hoist, stand on, Scales suitable for purpose, bed, hoist, stand on, • Immediately pre-surgical for bariatric patients availableImmediately pre-surgical for bariatric patients available• Reported weight or estimatedReported weight or estimated

• Knowledge of patient background, Knowledge of patient background, • type of surgery, type of surgery, • nutritional intake prior to surgery, nutritional intake prior to surgery, • amount of weight loss/timeamount of weight loss/time

• Potential for nutritional deficienciesPotential for nutritional deficiencies

Calculating nutritional requirements?Calculating nutritional requirements?

Energy requirementsEnergy requirements Non stressedNon stressed

Feed to BMR using actual body weightFeed to BMR using actual body weightwith -400-1000kcal for decrease in energy storeswith -400-1000kcal for decrease in energy stores

Mild to moderate stress:Mild to moderate stress: Calculate as normalCalculate as normal Omit stress and activity avoiding adverse effects of Omit stress and activity avoiding adverse effects of

overfeedingoverfeeding

Severe stressSevere stress Might be necessary to add a stress factor to BMRMight be necessary to add a stress factor to BMR

Obesity Double Check

In order of decreasing accuracy / evidence

1. Ireton Jones energy equations (critically ill but not ventilated)

2. Adjusted average weight (PENG pocket guide4)

3. 19-21 kcal/kg actual body weight (critically ill only) Glynn 1999, Alberda 2002

Protein RequirementsProtein Requirements44

0.2g N/kg Actual body weight x 6.250.2g N/kg Actual body weight x 6.25

And where And where BMI >30 use 75% of the value estimated from actual BMI >30 use 75% of the value estimated from actual

weightweight

BMI> 50 use 65% of the value estimated from actual BMI> 50 use 65% of the value estimated from actual weightweight

Fluid RequirementsFluid Requirements44

Very individual; ventilation, Very individual; ventilation, The guidelines err on side of cautionThe guidelines err on side of caution

Fluid requirements not a linear relationship with Fluid requirements not a linear relationship with weight, weight,

Avoid fluid overloadAvoid fluid overload

Consider, is volume sensible? 2000-3000mlsConsider, is volume sensible? 2000-3000mls Have losses been taken into accountHave losses been taken into account

Final thoughtsFinal thoughts

Estimated Energy requirements only starting Estimated Energy requirements only starting pointpoint

Review and monitor patient regularlyReview and monitor patient regularly Consider duration of nutritional support?Consider duration of nutritional support? Are nutritional goals being met?Are nutritional goals being met? Requirements change: patients clinical condition, Requirements change: patients clinical condition,

nutritional status, stress level, prognosisnutritional status, stress level, prognosis Never blindly follow guidelines: clinical Never blindly follow guidelines: clinical

judgement requiredjudgement required

ReferencesReferences1.1. American Society for Metabolic and Bariatric Surgery American Society for Metabolic and Bariatric Surgery

Guidelines 2008Guidelines 2008 2.2. Ernst B, Thurnheer M, Schmid S M, Schultes B. Evidence for Ernst B, Thurnheer M, Schmid S M, Schultes B. Evidence for

the necessity to systematically assess micronutrient status the necessity to systematically assess micronutrient status prior to bariatric surgery. Obesity Surgery. 2009; 19:66-73prior to bariatric surgery. Obesity Surgery. 2009; 19:66-73

3.3. Flancbaum L, Belsley S, Drake V, et al. Preoperative Flancbaum L, Belsley S, Drake V, et al. Preoperative nutritional status of patients undergoing Roux-en-Y gastric nutritional status of patients undergoing Roux-en-Y gastric bypass for morbid obesity. J Gastrointest Surg. bypass for morbid obesity. J Gastrointest Surg. 2006;10(7):1033-72006;10(7):1033-7

4.4. A Pocket Guide to Clinical Nutrition. 3A Pocket Guide to Clinical Nutrition. 3rdrd Edition. The Edition. The Parenteral and Enteral Nutrition Group of the British Parenteral and Enteral Nutrition Group of the British Dietetic Association. 2007Dietetic Association. 2007

5.5. Cheatham ML, Safcsak K, Brezinski SJ, et al Nitrogen Cheatham ML, Safcsak K, Brezinski SJ, et al Nitrogen balance, protein loss and open abdomen. Crit Care Med. balance, protein loss and open abdomen. Crit Care Med. 2007;35:127-1312007;35:127-131