Diabetes Overview by Dr McNulty

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  • An Overview of DiabetesSid McNultyConsultant Physician & Endocrinologist

  • Constructivism and Experiential learning and the brainSensoryIntegrativeMaking senseIntegrativePlanningMotor(plus verbal)Concrete experienceActive reflectionAbstract conceptualisationActive experimentation

  • Neuronal networksTap into and build on what the learner already knowsACEi actionsK+ sparingDiureticAntihypertensivePostural hypotensionInsulin actionHypoglycaemiaAddisonsLack of RAAS driveLack of insulin antagonismCushings opposite of Addisonsand therefore opposite of:Insulin and diuretics, and therefore.Blockage of RAAS

  • Diagnosis of DiabetesWHO (adopted in UK 6/00):Symptoms of hyperglycaemia plus 1 bloodRandom/2 hr plasma gluc > 11.1 mmol/l, orFasting plasma glucose > 7.0 mmol/lIn the absence of symptoms, there must be 2 plasma glucose results in the diabetic range on separate days.

  • Diagnostic dilemmaSensitivity: positives identified as positiveSpecificity: negatives identified as negative100% specificOver 10m longOver 15,000 mphOver 6,000 Km highNo false alarmsLots of false -ve100% sensitiveOver 1m longOver 10mphOff the groundDont miss a strikeLots of false +ve

  • Lethal Disease XAffects 1 in 10,000100% fatal horrible and painful deathFantastic test for it 99% (99% sensitive ie picks up disease as disease, and 99% specific ie picks up normal as normal)You have the test1 week later the resultsYou are positiveWhat is your probability you have disease?What do you do?

  • Please stand up

  • A Good Test

    ConditionPositiveNegativeTestResultPositiveTrue +veFalse +ve+ve predictive valueTP/TP+FPNegativeFalse -veTrue ve-ve predictive valueTN/TN+FNSensitivity 99%TP/TP+FN x100Specificity 99%TN/TN+FP x 100

  • A Good Test?

  • The Devil is in the detail!

  • A Good Test

    ConditionPositiveNegativeTestResultPositiveTrue +veFalse +ve+ve predictive valueTP/TP+FPNegativeFalse -veTrue ve-ve predictive valueTN/TN+FNSensitivity 99%TP/TP+FN x100Specificity 99%TN/TN+FP x 100

  • What tests meansSensitivity: about the diseasethe people you identify with the disease/total number with the disease (TP/TP+FN)if you have disease, you test positiveSpecificity: about the diseasethe people you identify without the disease/total number without the disease (TN/TN+FP) if you dont have disease you test negativePositive predictive value: about the testthe number of people you test positive with the disease/total number you test positive (TP/TP+FP) if you test positive, likelihood you have diseaseNegative predictive value: about the testthe number of people you test negative without the disease/total number you test negative (TN/TN+FN) if you test negative, likelihood you dont have the disease

  • Gedankenversuch

  • Test: being called mags to diagnose being a womanMaleFemaleTrue positiveFalsenegativeFalse positiveTruenegative

  • What being called mags meansSensitivity (disease): if youre a woman, how likely is it youll be called mags (low 1%)Specificity (disease): if youre not a woman, how likely is it youll not be called mags (v high 99.99%)Positive predictive value (test): if youre called mags, how likely are you to be a woman (high 99%)Negative predictive value (test): if youre not called mags, how likely youre not a woman (poor 50%)

  • Lethal Disease XAffects 1 in 10,000100% fatal horrible and painful deathFantastic test for it 99% (99% sensitive ie picks up disease as disease, and 99% specific ie picks up normal as normal)You have the test1 week later the resultsYou are positiveWhat is your probability you have disease?What do you do?

  • Please stand up, again

  • One million people1 in 10,000 with disease1 in 100 with false +ve1 in 10,000 with disease and +ve test ie 100 people1 in 100 with +ve test and no diseaseie 10,000 people

  • One million peopleHow many have disease?1 in 10,000100 peopleHow many would test positive?1 in 10010,000If positive do you have disease? What is the positive predictive valueTP/TP+FP: 100/10,100ie 1 in 100 chance!

    Therefore even the best test should be interpreted with clinical data, and should only be asked for in the right people (ETT ECGs, VQs etc etc)

  • What tests meansSensitivity: about the diseasethe people you identify with the disease/total number with the disease (TP/TP+FN)if you have disease, you test positiveSpecificity: about the diseasethe people you identify without the disease/total number without the disease (TN/TN+FP) if you dont have disease you test negativePositive predictive value: about the testthe number of people you test positive with the disease/total number you test positive (TP/TP+FP) if you test positive, likelihood you have diseaseNegative predictive value: about the testthe number of people you test negative without the disease/total number you test negative (TN/TN+FN) if you test negative, likelihood you dont have the disease

  • Incidence of DiabetesThe incidence is increasing steeplyWorld diabetic population is estimated to reach 221 million people by 2010 (double the number in 1994).Over 1.4 million people in the United Kingdom (3% of the pop) have diagnosed diabetes mellitus, with perhaps another million as yet undiagnosed.Amos AF et al.The rising global burden of diabetes...Diabetic Med 1997;14(suppl 5):S1-85.

  • Types of diabetesType 1 (IDDM)Absolute insulin deficiency-cell failureYoung, thinProne to DKAType 2 (NIDDM)Relative insulin deficiencyInsulin resistanceOld, BMI (kg/m2)Usually on tablets or diet (can be on insulin)No DKA : instead HONK

  • Insulin balance with age T1DM Event

  • Obesity and T2DMObesityInactivityInsulin resistanceHyperglycaemiaMicro- and macro-vascular complicationsHypertensionDyslipidaemiaEndothelial dysfunctionProthombotic state

  • The Progress to T2DMWt 70 kgRequires 60 UPanc Res 200 ULevel: 60 UNormalWt 100 kgRequires 150 UPR 200 ULevel: 150 UNormalWt 70 kgRequires 60 UPanc Res 100 ULevel: 60 UNormalWt 100 kgRequires 150 UPanc Res 100 ULevel: 100 UDM & Hyperinsulin

    NORMALT2DM

  • 12 v 121 v 1210 units?8 v 81 v 810 units/hr?50 v 501 v 5010 units/50ml?1010 units Actrapid at 100 mls/hr?

  • Insulin balance with age T2DM

  • Insulin balance with age T2DM

  • Why worry with diabetic in-patientsAvoid emergencies:Main aim of your MxPlus tighten peri-operative glucose control

  • Diabetic emergenciesHypoglycaemiaHyperglycaemiaDKA: Type 1HHS/HONK: Type 2

  • HypoglycaemiaBMs 2-4Autonomic symptoms: SympatheticSweaty, agitated, nausea, shaky, pale, hungry

    BMs 0-2Neuroglycopenic:Confusion, aggression, agitation, coma, hemiparesis etc

  • Mechanism of Normoglycaemia cellProinsulinInsulinC Peptide GlucosePancreasPancreasGlucagonGlycogenLiver Glucose

  • Mechanism of Hypoglycaemia cellProinsulinInsulinC Peptide GlucosePancreasPancreasGlucagonGlycogenLiver Glucose1.Sulphonylureas3.Exogenous4.Lack of antagonist(cortisol etc)5.IGF 26.Excess use2.Excess7.Lack of8.Lack of

  • Treatment of HypoTreatment:IV glucose 50ml 50%IM glucagon 1 mg

    ?Treat causesteroids (Addisons, NICTH)surgery (Insulinoma, NICTH)Diazoxide & high dose BFZ (Paliative Insulinoma)DSN review/ Psych review

  • Presentation & definition of DKAYoung, thin, T1DMPoly-uria, -dypsia, weight loss (passing sugar water)SOB (kussmal - blowing off CO2 to pH), dehydrated, BP, vasodilated, drowsy

    Raised blood glucose (>15 mmol/L)Metabolic acidosis:pH

  • Mechanism of DKAIntercurrent illnessIncreased counter-regulatory hormones (Cats and cortisol)Severe insulin deficiencyHyperglycaemia

  • Mechanism of DKAHormone-sensitive lipaseTriglycerideNon-esterified fatty acidsAcetoacetate3-HydroxybutyrateAcetoneGlycerol+Insulin-

  • Mechanism of DKAIntercurrent illnessIncreased counter-regulatory hormones (Cats and cortisol)Severe insulin deficiencyHormone-sensitive lipaseTriglycerideNon-esterified fatty acidsAcetoacetate3-HydroxybutyrateAcetoneGlycerol+++Hyperglycaemia

  • Mechanism of DKAHyperglycaemiaKetone bodiesOsmotic diuresisVomitingAcidosisElectrolytedepletionDehydrationVasodilatationHypotensionHypothermia

  • Management of DKA GeneralNG tubeReduced consciousnessGastroparesisIV access? Central line only if indicatedCatheter?UTI may have precipitated DKADehydrated and immunosuppressedSerious risk of introducing ascending infectionTherefore only if not PUd in 3 hoursRemove / treat precipitator (low threshold for Abs)?Heparin (coma or Osmolality >350 mOsm/L)

  • Management DKA SpecificT1DMAcute decompensationpH
  • 13th May 2010Died July 1997Retired last year and still facing 12 charges!

  • HyperOsmotic NonKetotic Coma (AKA) Hyperglycaemic HyperOsmolar Syndrome Presentation & DefinitionIn Type 2 DMLonger Hx -poly-uria/dypsiaDehydration, BP, unwell

    High RBG (usually >>30 mmol/L)Osmolality >350 (Na+ + K+) x2 + Urea + Glucose = Osmol

  • Management of HHS SummaryT2DM, older, co-morbidity, more sickOsmol > 350 mmol/LtrGluc usually >>30 mmol/LtrSame general management as DKAIV insulin 0.1 units/kg/hr = 6-8 units/hourIV fluids 3-5 Ltr/24hrGo more gentle!?Full heparin doseAbs, MI screen etcInform your senior

  • GKI/Alberti (to give insulin to T1DM)15 units Actrapid500 ml 10% Dextrose10 mmol KCl80-100ml/hourIf BMs high add another 5 units (and on)If BMs low add 5 units less (and on)Check K 1 hour before bag change

    Restart sc insulin 1/2 hour before eating

  • Complications & DiabetesMicrovascular v Macrovascular

    KNIVESK - kidneysN - nervesI - impotence, infectionV vascular (IHD, CVA, PVD)E - eyesS - skin in