PREOPERATIVE ASSESSMENT

PREOPERATIVE ASSESSMENT
• The presence of risk factors increase both morbidity and mortality
• Anaesthetic Death: death associated with anaesthesia and surgery and are usually due to presence of high risk factor rather than anaesthetic fault .
• Operative mortality includes all death occurring within 30 postoperative days(even if the patient was discharged)
• Inadequate preparation of patient may be a major factor to primary anaesthetic causes of perioperative mortality
• It is essential that the anaesthetist visit every patient in the ward before surgery to assess fitness for anaesthesia
o All patients have to cease smoking for at least 12h prior to surgery because :1/nicotine action on the sympathetic system producing tachycardia, hypertension ,and increase coronary vascular resistance(cessation of smoking improves angina symptom ).2/heavy smoking reduces available oxygen by 23% due to haemoglobin conversion to carboxyhaemoglobin
o Regular alcohol intake lead to induction of liver enzymes resulting in tolerance to anaesthsia
o Drugs may interfere with anaesthetic agents : antihypertensive agents may interact with anaesthetic agents causing hypotension
o Anticoagulant use is of special importance it may cause bleeding during intubation and during operation. i.m injection must be avoided and subarachnoid/extradural block must also be avoided .***patient must be admitted to stop ora anticoagulants (warfarin) 3days prior to surgery replaced by i.v. heparin infusion for immediate action .heparin is short acting and easily reversed by protamine sulphate:every 1 gm neutralizes 100 units heparin on mucous surface or80 units of heparin in lung in case of bleeding…during surgery patient is given heparin continuous i.v. infusion of 1000 unit/h and following operation oral anticoagulant can be restarted and heparin infusion can be withdrawn after 3 days.