Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Perioperative Management Intern Survival Kit Dr Chee Choy Senior Medical Registrar Topics Management of antiplatelets/anticoagulation Perioperative management of diabetes mellitus Evaluating and managing cardiac risk in patients undergoing non-cardiac surgery Perioperative management of respiratory and sleep condition Anti-platelets post-PCI Aspirin + Clopidogrel continued for at least recommended duration BMS – 3-6/12 (at least 1/12) DES – 12/12 Perioperative management of antiplatelets Aspirin Continue, EXCEPT for urology, plastics & ophthalmology or if specific request Clopidogrel Long duration of clinical action (half life of a platelet being ~10 days) For platelet activity to return to completely normal – needs to be stopped for 7 days Cessation of clopidogrel for 5 days will allow turnover of ~ 50% of platelets (adequate platelet activity) Anticoagulation for AF CHADS2 0 1 2 3 4 5-6 Events/100 person years Events/100 person years Warfarin 0.25 No warfarin 0.49 0.72 1.27 2.20 1.52 2.50 5.27 2.35 4.60 6.02 6.88 CHADS2 <2 = Aspirin CHADS2 ≥ 2 = Warfarin CHADS2 -> CHA2DS2VASc CHADS2 Risk Score CHA2DS2-VASc Risk Score CHF 1 CHF or LVEF < 40% 1 Hypertension 1 Hypertension 1 Age > 75 2 Diabetes 1 Stroke/TIA/ 2 Age > 75 1 Diabetes 1 Stroke or TIA 2 From ESC AF Guidelines http://www.escardio.org/guidelines-surveys/escguidelines/GuidelinesDocuments/guidelines-afib-FT.pdf Thromboembolism Vascular Disease 1 Age 65 - 74 1 Female 1 New guidelines for use of OAC for stroke prevention in AF In prosthetic heart valves: Risk of systemic embolisation = 4% With aspirin = 2.2% With warfarin 0.7-1.0% Perioperative management of anticoagulation Risk Stratification Low thromboembolic risk Uncomplicated AF (No stroke or arterial embolisation in last 12 months) Biological heart valve > 3 months after implantation Mechanical aortic valve Non-recurrent systemic arterial embolism High thromboembolic risk AF with LV systolic dysfunction / Stroke or systemic embolus in last 12 months Biological heart valve < 3 months after implantation Mechanical mitral / tricuspid valve, multiple mechanical valves, older aortic valves Venous thrombosis within last 3 months / Recurrent thrombosis Recurrent systemic arterial embolism *2 low-risk factors = high risk Perioperative management of anticoagulation Recommendations Low risk High risk Pre-op Withhold warfarin 5 days before Night before: 1-2mg PO Vit K if INR > 2 Operate if INR < 1.5 If >1.5, 0.5 – 1.0 mg IV Vit K and Prothrombinex-HT 10-15 units/kg and consider 1-2 units FFP if urgent surgery Withhold warfarin 5 days before Bridging anticoagulation 2-3 days pre-op -UFH, aiming APTT 1.5x normal (Stop 6 hours pre-op) OR -LMWH (Stop 12 hours pre-op) Post-op Restart warfarin on day of surgery Restart warfarin ASAP Heparin or LMWH for DVT prophylaxis If very high risk - Cover with heparin or LMWH until INR therapeutic for 48 hrs Guidelines for reversal of Warfarin Warfarin reversal: consensus guidelines, on behalf of the Australasian Society of Thrombosis and Haemostasis. Baker RI, Coughlin PB, Gallus AS, Harper PL, Salem HH, Wood EM. Med J Aust 2004;181(9):492-7. How About Dabigatran ? Quick onset of action Withhold 24hrs or 48hrs (if creatine clearance <50) for minor procedure Withhold 2-4 days for major surgery and consult haematology Perioperative management of diabetes mellitus Increasingly common disorder 20% of surgical pts have DM Increased incidence of CV disease/silent ischaemia Surgery + anaesthesia -> increased stress response -> hyperglycaemia Goals: Maintenance of fluids + electrolytes Prevention of ketoacidosis Avoid hyperglycaemia Avoid hypoglycaemia Perioperative management of diabetes mellitus T2DM – diet controlled BSL monitoring T2DM – OHG / noninsulin injectables Continue usual medications until morning of surgery WH morning OHG Sulfonylureas – increase risk of hypoglycaemia Metformin – contraindicated due to lactic acidosis Thiazolidinediones – increase fluid retention/oedema, may precipitate CCF DPP-IV inhibitors/GLP-1 analogues – alter GI mobility Treat hyperglycaemia (BSL > 10 mmol/L) with short acting insulin (sliding scale) Restart OHG post-op once eating, except Metformin (until renal function normal) BSL monitoring Perioperative management of diabetes mellitus T2DM or T1DM – insulin Put 1st on Surgical list Take usual insulin until morning of surgery Check BSLs 2/24 (aim for 4-8 mmol/L) In the absence of not eating, basal metabolic rate utilise ½ of individual’s insulin When fasting ½ dose of insulin (intermediate + short acting) as intermediate acting insulin only Dextrose containing IVT OR Insulin infusion for tight control DO NOT WITHOLD INSULIN IN T1DM – may precipitate ketoacidosis Evaluating cardiac risk for patients undergoing non-cardiac surgery Cardiac complications are some of the most common risks perioperatively (5.8%) Cardiovascular risk in surgery In non-selected pts >40 MI 1.4%, cardiac mortality 1% In surgical pts with some selection criteria MI 3.2%, cardiac mortality 1.7% In patients selected to undergo preoperative thallium scintigraphy MI 6.9 %, cardiac mortality 3.2% Patients with underlying vascular disease (ie. PVD, stroke) 5x increase in incidence of significant CAD, LV dysfunction (EF <40%) More susceptible to myocardial ischaemia volume shifts, blood loss, tachycardia, HT -> myocardial demand Principals of the preoperative cardiac evaluation Provide clinical judgment, not clearance for surgery What is the patient’s risk of complications (cardiac and noncardiac)? Would further risk stratification alter patient management? Can anything be done to reduce the patient’s risk? Order tests only when results may change management Routine tests are not good screening devices Healthy patients may not need testing Patients undergoing minimally invasive procedures may not need testing Evaluating cardiac risk for patients undergoing non-cardiac surgery Identify patients at high risk so that appropriate testing and therapeutic measures can be undertaken to minimise this risk Clinical risk Functional status Underlying risk of surgical procedure Clinical Risk Major predictors Functional capacity Important determinant of risk is the patient’s functional capacity. Metabolic equivalents (1 MET is defined as 3.5 mL O2 uptake/kg per min) Self-reported exercise tolerance and the risk of serious perioperative complications; Reilly DF, McNeely MJ, Doerner D, Greenberg DL, Staiger TO, Geist MJ, Vedovatti PA, Arch Intern Med. 1999;159(18):2185. A study of 600 patients undergoing major noncardiac procedures Poor self-reported exercise capacity, defined as an inability to walk four blocks or climb two flights of stairs, associated with significantly more perioperative complications than was good exercise capacity. Functional capacity Surgery Specific Risk Risk Category Cardiac Morbidity Rates Examples High (Vascular) > 5% Aortic and other major vascular surgery Peripheral vascular surgery Intermediate 1- 5% Intraperitoneal and intrathoracic surgery Carotid endarterectomy Head and neck surgery Orthopedic surgery Prostate surgery Low < 1% Do not generally require further preoperative cardiac testing Endoscopic procedures Superficial procedure Cataract surgery Breast surgery Ambulatory surgery Cardiac risk stratification for noncardiac surgery - Algorithm Cardiac Investigations Investigations should be done only if the cardiac condition in its own right warrants it Not appropriate to undertake stress testing &/or coronary angiography in order to identify well – controlled or asymptomatic coronary disease, purely for the purpose of assessing perioperative risk Recommendations for pre-operative stress testing In general, the indications for stress testing are: Significant ischaemic symptoms If high chance of having IHD, undergoing high risk surgery, when the identification of ischaemia will lead to postponement of surgery and further cardiac treatment Pre-op revascularisation In patients with +ve stress test -> angiography In pts with high-risk features -> revascularisation High risk USA or NSTEMI Acute STEMI Angina + LMCA or triple vessel disease Angina + 2-vessel disease including prox LAD + LV dysfunction / reversible ischaemia on stress test CABG recommended if pt has CAD which warrants CABG and non-cardiac surgery can be postponed PCI recommended if pt has CAD suitable for PCI, or surgery cannot be postponed Balloon >7 days angioplasty if possible, delay surgery Perioperative Management for respiratory and sleep conditions Asthma and COPD - Make sure patient is stable preoperative - Postpone non urgent surgery if needed OSA If suspicious -> sleep study Must bring CPAP to hospital References PROMPT Procedures and Policies Internet explorer → NH Intranet → Prompt – Policies and Procedures (Left hand side) → Click here to search for Policies and Procedures → Enter search term - “Perioperative management of antiplatelet agents” - “Perioperative management of anticoagulation” - “Anticoagulated patients requiring invasive procedures” - “Anaesthesia and perioperative medicine” - “Guidelines for reversal of oral anticogulation” UpToDate Therapeutic Guidelines Acknowledgements to Notes by Drs. Rinku Rayoo, Tina Lin, Karen Lim & Sara Baqar Thank You