Pre anaesthesia

• Preoperative assessment (POA)


  Medical history and examination of a patient prior to surgery with a view to planning optimal care before, during and after surgery
• Factors considered in preoperative assessment

  • The health of the patient
  • The urgency and nature/type of the surgery
  • Any relevant investigations
• Pre-anaesthetic Assessment

  Specific enquiries must be made about: Angina, Previous myocardial infarction and subsequent symptoms, Symptoms indicating heart failure
• Heart failure


  Will be worsened by the depressant effects impairing the perfusion of vital organs
• Myocardial infarction


  Are at a greater risk of perioperative reinfarction
• Intraop


  Any hypotension or hypertension will expose the patient to MI
• Postop

  Must maintain good analgesia postoperatively to prevent tachycardia due to pain which might cause another MI
• Elective surgery


  Postponed until at least 6 months after the event (MI), no matter what kind of anesthesia
• Untreated or poorly controlled hypertension

  May lead to exaggerated cardiovascular responses. Must wait at least 2 weeks after controlling it, may lead to intracerebral hemorrhage
• Hypertension and hypotension

  Can be precipitated, which increases the risk of myocardial ischemia
• Anesthetizing patient with poorly controlled BP


  The patient will have fluctuations in his BP during anesthesia
• Intubation with laryngoscope

  Severe heart depression may lead to MI
• Induction of the anesthetic drug

  Patient might have severe hypotension, bradycardia, and will arrest due to the reverse in his hypertension, he will have exaggerated response to the pain
• All HTN patients

  Have a high systemic vascular resistance, severe vasoconstriction, low CO, any vasodilation will lead to severe hypotension
• Valvular heart disease


  Prosthetic valves may be on anticoagulants, need to be stopped or changed prior to surgery and give Antibiotic prophylaxis
• Patients on anticoagulants

  Warfarin must be stopped 5 days before surgery and switched to heparin, heparin must be stopped 4 hours before surgery. Give patient prophylactic antibiotics
• Obstructive lesions and regurgitation

  AS, MS, and pulmonary HTN easily decompensate, can't tolerate vasodilatation. Regurgitation can't tolerate bradycardia
• Echo


  Should be done for cardiac patients
• Renal impairment patients

  Urea, creatinine, potassium level should be checked
• Patients with pre-existing lung disease

  Prone to postoperative chest infections if they are obese or undergoing upper abdominal or thoracic surgery with history of lung disease and sputum production (volume and color)
• Upper respiratory tract infection

  Anesthesia and surgery should be postponed "at least two weeks free of symptoms Preoperatively" unless it is for a life-threatening condition
• Most of the cancelation of the surgeries

  Are due to URI (especially with the pediatrics)
• With GA

  There is a high chance of transferring infection from URT to LRT
• Any patient with BA or COPD

  Should have chest physiotherapy before surgery
• Enquire about inherited or 'family' diseases

  Sickle-cell disease, porphyria, pseudocholinesterase deficiency, malignant hyperthermia
• Difficulties with previous anesthetics

  Nausea, vomiting are common in females, hydrate the patient if she had a history of such complication
• Pt. with bronchiectasis should take antibiotics
• Inherited or 'family' diseases

  • sickle-cell disease
  • porphyria
  • pseudocholinesterase deficiency
  • malignant hyperthermia
• Difficulties with previous anesthetics: Nausea, vomiting → hydrate the pt and use multimodal antiemetics for females with a history of such complications
• Awareness during surgery: Hear everything but can not move "Paralysed"
• Postoperative jaundice may indicate hepatic injury
• Diabetes patients have an increased incidence of: Ischaemic heart disease, Renal dysfunction, Autonomic and peripheral neuropathy
• Intra- and postoperative complications for diabetes patients

  1. Measure fasting blood glucose prior to the OR

  2. Fear hypoglycemia more than hyperglycemia due to risk of brain injury (Hypoglycemic encephalopathy)

  3. Check blood glucose frequently intraop

  4. Maintain blood glucose around 6-8 mmol
• Smoking leads to increased cough during intubation and stimulates the sympathetic nervous system causing tachycardia, hypertension, and coronary artery narrowing
• Smoking affects wound healing, makes the patient prone to infections, and delays recovery
• Alcohol induction of liver enzymes, tolerance, hepatic and cardiac damage, delirium tremens may occur during postoperative recovery
• Physical examination: Full physical examination should be undertaken and documented in the case records
• American Society of Anesthesiologists fasting guidelines

  • Clear liquids - 2 hours
  • Breast milk - 4 hours
  • Infant formula - 6 hours
  • Non-human milk - 6 hours
  • Light meal - 6 hours
• Premedication refers to the administration of drugs in the period of one to two hours before induction of anaesthesia
• Premedication objectives

  • Allay anxiety and fear
  • Reduce secretions
  • Enhance the hypnotic effect of general anaesthetic agents
  • Reduce postoperative nausea and vomiting
  • Produce amnesia
  • Reduce the volume and increase the pH of gastric content
  • Attenuate vagal reflexes
  • Attenuate sympathoadrenal responses
  • To give concomitant drugs