Obesity and Endocrine Disorders Dr EM Selepe MBChB(Natal) FCA(SA) 1 Military Hospital Thaba Tshwane 1

Obesity Definition O Excess of body fat sufficient to adversely affect health O BMI is used as the surrogate marker O Obesity is often defined in terms of the BMI O BMI does not take body build into consideration and hence can be misleading in the presence of large muscle mass O Fat distribution can be central (abdominal) or gluteo-femoral O Central obesity has increased CVS risk factors 2

Obesity Assessment O BMI commonly used O Waist to hip circumference ratio (WHR) can be used or waist circumference alone O Using BMI Wt/Ht squared (kg/m2) O WHO classification: 1. <18,5 Underweight Healthy – 29.9 Overweight – 39 Obese 5. >40 Morbid Obesity 3

Obesity Assessment “Cont” O WHR (waist to hip ratio) O Male >1.0 Female >0.9 O Waist circum Male> 103cm and female >88 cm O Generally Waist < 100cm suggests insulin resistance less likely in all sexes 4

Epidemiology O Rapid increase in both developed and developing countries O Prevalence on the increase stats from the UK: % of male and 8% of female increase to 21% and 21.4% respectively 3. Now 55% of population is overweight or obese 5

Clinical Problems O Psycho-social: 1. Poor self esteem and image 2. Depression 3. Withdrawn O Medical: 1. Gastro-oesophageal disease (GED) 2. Secondary hypertension 3. Pulmonary hypertension 4. Obstructive sleep apnoea (OSA) 6

Anaesthetic Practice O Upper airway 1. Short neck, neck circumference (male 42cm, female 41cm) 2. Fat padding 3. Large face- difficulty in holding mask 4. Mallampati grades 3 to 4, Thyromental <6cm and sternomental < 12cm distance 5. Poor mouth opening 7

Anaesthetic Practice “cont” O Lower Airway: 1. Poor lung compliance 2. Increased airway resistance – chest bulk 3. Higher peak airway pressures 4. Pulmonary hypertension 5. Decreased FRC leading to atelectasis and hypoxia 6. Increased abdominal pressure decreasing the FRC ( Functional residual capacity ) 8

Anaesthetic Practice “Cont” O Cardio-vascular System: 1. Secondary hypertension 2. LVH, LAH leading to diastolic dysfunction 3. RVH from pulmonary hypertension leading to RHF 4. Prone to DVT and pulmonary thromboembolism – worsening pulmonary HPT 5. OSA leads to hypercapnia, sympathetic over stimulation worsening pulmonary and systemic hypertension. 9

Anaesthetic practice “cont” O GIT 1. Gastric emptying- delyed, potential full stomach 2. Gastroeosophageal disease ( reflux) 3. Associated disease ( hiatus hernia) 4. Pressure on the splanchnic vessels compromises liver perfusion. 10

Anaesthetic considerations Anticipated problems: O Airway management O Potential full stomach ( starvation period prolonged, ulcer prophylaxis ) O Positioning of patient and intravenous access O Co - morbid diseases O Possible post op high care or ICU – OSA O Deep venous thrombosis prophylaxis 11

Endocrine Disorders ( Metabolic Syndrome ) O Components 1. > Waist circumference 2. Increased insulin resistance ( Diabetes mellitus) 3. high LDL, decreased HDL 4. Hypertension 12

Diabetes mellitus and Obesity O There is increased incidence of obesity and Diabetes O Obese patients have increased resistance to insulin. O Type 2 diabetes is common in these population O Commonly on oral hypoglycaemics and or insulin. 13

Diagnostic Criteria ( WHO classification) Venous plasma glucose ( mmol/l) NormalFasting 2hrs post prandial <6.0 <7.8 diabeticFasting 2hr post prandial >7.0 >11.1 IGT (Impaired glucose tolerance) Fasting 2hr post prandial <7.0 >7.8 – 11.1 IFG (Impaired fasting glucose) Fasting

Aims of Treatment O Sensitize receptors (thiazolidinediones, Biguanides ) O Increases the B cells production of insulin( sulphonylurea, Biguanides, GLP I (glucagon like peptide 1) ) O Decrease absorption (alpha1 gylcosidase inhibitors) O Insulin replacement 15

Anaesthetic considerations O Uncontrolled DM 1. Dehydration (polyuria, polydypsia) 2. Hyperosmolality (HONK) 3. Sepsis O Chronic DM 1. Potential full stomach 2. Autonomic and peripheral neuropathy 3. Coronary artery diseases and HPT 4. Kidney dysfunction/failure 16

Conclusion O There is an accelerated prevalence of obesity and diabetes mellitus in South Africa and knowledge of the two entities is of essence as it is also part of metabolic syndrome. O Airway management and the clinical dynamics of the two should be well appreciated. 17