Transcript Anesthesia
GHAZI ALDEHAYAT MD Ancient and Mediaeval times Anesthesia Anesthesia Intensive care Chronic pain management Anesthesia Anesthesia CPR Acute Pain control Difficult Lines Evaluating critical patints Anesthesia Theatre Radiology Interventional radiology Cardiology ECT GI Types Of Anesthesia Types of Anesthesia General Anesthesia Local Anesthesia Sedation General Anesthesia Preoperative evaluation Intraoperative management Postoperative management Purpose of preoperative visit Medical assessment of the patient. Decide the type of anesthesia. Establish rapport with the patient. Allay anxiety and decrease pain. Obtain informed consent. Ask for further investigation. Decide risk versus benefit . Prescribe medications. Pre-Operative Assessment History Indication for surgery Surgical/anesthetic hx: previous anesthetics/complications, previous intubations, Medications, drug allergies • Medical history CNS: seizures, CVA, raised ICP, spinal disease, arteriovenous malformations CVS: CAD, MI, CHF, HTN, valvular disease, dysrhmias, PVD, conditions requiring endocarditis prophylaxis, exercise tolerance, CCS class, NYHA class Resp: smoking, asthma, COPD, recent URTI, sleep apnea GI: GERD, liver disease Renal: insufficiency, dialysis Hematologic: anemia, coagulopathies, blood dyscrasias MSK: conditions associated with difficult intubations – arthritis, RA, cervical tumours, cervical infections/abscess, trauma to C-spine, Down syndrome, scleroderma, obesity Endocrine: diabetes, thyroid, adrenal disorders Other: morbid obesity, pregnancy, ethanol/other drug use FHx: malignant hyperthermia, atypical cholinesterase (pseudocholinesterase), other abnormal drug reactions Physical Examination Physical exams of all systems. Airway assessment to determine the likelihood of difficult intubation Bony landmarks and suitability of areas for regional anesthesia if relevant Focused physical exam on CNS, CVS and respiratory (includes airway) systems General, e.g. nutritional, hydration, and mental status Pre-existing motor and sensory deficits Sites for IV, central venous pressure (CVP) and pulmonary artery (PA) catheters, regional anesthesia Investigations: According to( ranged from none to most comlicated) Age Surgery Medical condition As clinically indicated Low risk – no further evaluation needed Intermediate risk – non-invasive stress testing High risk – proper optimization +/delaying/canceling procedure American Society of Anesthesiology (ASA) classification Common classification of physical status at time of surgery A gross predictor of overall outcome, NOT used as stratification for anesthetic risk (mortality rates) ASA 1: a healthy, fit patient (0.06-0.08%) ASA 2: a patient with mild systemic disease, e.g. controlled Type 2 diabetes, controlled essential HTN, obesity (0.27-0.4%), smoker ASA 3: a patient with severe systemic disease that limits activity, e.g. angina, prior MI, COPD (1.8-4.3%), DM, obesity ASA 4: a patient with incapacitating disease that is a constant threat to life, e.g. CHF, renal failure, acute respiratory failure (7.8-23%) ASA 5: a moribund patient not expected to survive 24 hours with/without surgery, e.g. ruptured abdominal aortic aneurysm (AAA). ASA 6 : Brain death patient For emergency operations, add the letter E after classification Medications: Pay particular attention to CVS and resp meds, narcotics and drugs with many side effects and interactions• prophylaxis. Risk of GE reflux: Na citrate 30 cc PO 30 mins hour pre-op. Risk of adrenal suppression – steroid coverage Risk of DVT – heparin SC,LMW Heparin, Mechanical methods. Optimization of co-existing disease ^ bronchodilators (COPD, asthma), nitroglycerine and beta-blockers (CAD risk factors) Pre-operative medications to stop: Oral hypoglycemics – stop on morning of surgery Antidepressants. Pre-operative medication to adjust: Insulin, prednisone, coumadin, bronchodilator Decide, whether to proceed with surgery ,to send patient for further management or to cancel the operation. Discus anesthetic options. Decide which is the most useful for the patient. Informed concent. Risk stratification . Types of anesthesia GENRAL ANESTHESIA REGIONAL ANESTHESIA LOCAL ANESTHESIA. GENERAL ANESTHESIA Airway management Endotracheal intubation( Body cavities, Full stomach, prone position, compromised, Very long operations, Airway involvment ) Laryngeal mask Airway( peripheral, No indication for ETT) Mask( very short, no indication for ETT) Ventilation Spontaneous ( No muscle relaxant) Controlled ( With muscle relaxant) GENERAL ANESTHESIA PREPARATION monitoring position Intravenous fluid Warming CONDUCT OF ANESTHESIA PERIOPERATIVE MEDICINE Monitoring: according to paitent medical condition and surgery proposed Basic: ECG, NIBP,SpO2, EtCO2, Temp,FiO2, Anesthetic gases, Airway pressure, The presence of anesthetist all throug procedure. Others: Nerve stimulator, Invasive Bp, CVP, CO, BIS, PA Catheter, TEE, UO Lab tests, ABGs, CBC, LFT , Coagulation, TEG Basic Principles of Anesthesia Anesthesia defined as the abolition of sensation Analgesia defined as the abolition of pain “Triad of General Anesthesia” need for unconsciousness need for analgesia need for muscle relaxation Hypnosis (unconsciousness ) Induction Maintinance Recovery Intravenous(eg:T hiopentone,Prop ofol) Inhalational( sevoflurane,Halo thane) Inhalational Intravenous Discontinue Analgesia Systemic( opiods, Fentanyl,Remifen tanil,Alfentanil) Muscle Relaxation Depolarizing (suxamethoniom ) Non Depolarizing (steroids, vecuronium) Benzylisoquinolo nium Cis atracurium) Systemic: Goo)Multimodal) (opiods,NSAIDS) d Analgesi Regional( Opioids,Regional Epidural,Spinal) , Local LA NSAIDS N2O Parasetamol Non Reversal by Depolarizing Anticholinstrases ( Neostigmine,)& Atropine Intravenous Anesthetic Agents Thiopental Thiobarbiturates Uses for iduction, decrease ICP, Status epilepticus CNS: Hypnosis within 30 seconds ,decreased intracrainial pressure. CVS depression, hypotension, tachycardia Respiratory depression, spasm CI: porphyria Arterial injection Intravenous Anesthetic Agents PROPOFOL ( Deprivan) USES: induction, maintenance, sedation in the ICU, sedation Contra indicated in children. CNS: Hypnosis within 30 seconds ,decreased intracrainial pressure. CVS: depression more than Thiopental Respiratory: Depression, no spasm Caloric load in the ICU, propfol infusion syndrome Intravenous Anesthetic Agents Ketamine Phencyclidine Uses, shock, burn, field. CNS, dissociation, hallucination, analgesia, Increased intracrainial pressure. CVS Stimulation, hypertension, tachycardia Respiratory, less depression. Intravenous Anesthetic Agents Etomidate Stable cardiovascular Steroid depression Inhalational Anaesthesia Halothane Enflurane Isoflurane Sevoflurane Desflurane N2o Xenon Inhalational Anesthesia induced by inhalational effec Tdifferent in their potency, indicated by MAC. Different in rapidity of induction and recovery. Common pharmacological properties, CVS depression with tachy or bradycardia REP Depression. CNS increased intracranial pressure Opioid Fentanyl Morphine Alfentanl Remifentanil All have almost the same pharmacodynamics of , Morphine, Analgesia, Sedation , Respiratory depression, Nausea and vomiting, meiosis, constipation. Different in their pharmakokinitcs. Muscle relaxant Depolarizing Suxamethonium Short acting, rapid onset, Many Side effects, hyperkalemia, arrythmias, Muscle pain ,Scoline apnea. Non Depolarizing: Aminosteroid ; organ metabolism Benzylisoquinolonium: Histamine release, Long acting Local anaesthetics Lidocaine, lignocaine,xylocaine Bupivacaine ( marcaine) Cocaine Procaine Regional ( spinal , epidural) Local Different side effects Marcaine CI by intravenous LA toxicity. Maximum doses, Perioral numbness, tinnitus, conulsions, resp depression, Cardiac arrest Treatment, ABC, symptomatic, intralipid( propofol) Reversal Neostigmine Atropine Monitoring Basic ( ECG, BP, SPO2, EtCO2) Observation Advanced ( IBP , CVP, CO ….ETc Awareness Awarness Definition Types Effect Causes Manegment Thank you