Prepared by Dr. Mahmoud Abdel-Khalek Aug 2015 Preoperative Evaluation, Preparation and Premedication

Preoperative Evaluation Anesthetic plan, should consider the following: Medical illness (Hypertension, diabetes…etc) Surgical illness (thyroid enlargement, cancer larynx) Drug sensitivities (thiopental, propofol) The planned operation (thyroidectomy, laryngectomy) Previous anesthetic experiences Psychological makeup.

The preoperative visit The purpose of the pre-operative visit: Problems identifications Risk assessment Getting informed consent Establish a strong doctor – patient relationship Relieving the anxiety of the patient

Problems identification through: History (including a review of medical records) Physical examination Any indicated laboratory tests Assessments may require having advise from other specialties

History Patient's medical problems e.g. DM, HTN Planned procedure (surgical, therapeutic, or diagnostic) Known sensitivity to drugs Current or prior medications The use of tobacco, alcohol, drugs such as marijuana, cocaine and heroin Detailed questioning about previous operations and anesthetics (very important) A family history of anesthetic problems (malignant hyperthermia)

Problem Identification Cardiovascular : hypertension ; ischemic, valvular or congenital heart disease; CHF or cardiomyopathy,, arrhythmias Cardiovascular : hypertension ; ischemic, valvular or congenital heart disease; CHF or cardiomyopathy,, arrhythmias Respiratory : smoking; COPD; restrictive lung disease; altered control of breathing (obstructive sleep apnea, CNS disorders, etc.) Respiratory : smoking; COPD; restrictive lung disease; altered control of breathing (obstructive sleep apnea, CNS disorders, etc.) Neuromuscular : raised ICP ; TIA's or CVA's; seizures; spinal cord Injury; disorders of NM junction e.g myasthenia gravis, muscular dystrophies,MH Neuromuscular : raised ICP ; TIA's or CVA's; seizures; spinal cord Injury; disorders of NM junction e.g myasthenia gravis, muscular dystrophies,MH Endocrlne : DM; thyroid disease; pheochromocytoma; steroid therapy Endocrlne : DM; thyroid disease; pheochromocytoma; steroid therapy GI - Hepatic : hepatic disease; gastresophageal reflux GI - Hepatic : hepatic disease; gastresophageal reflux

Renal : renal failure Renal : renal failure Hematologic : anemias; coagulopathies Hematologic : anemias; coagulopathies Elderly, Children, Pregnancy Elderly, Children, Pregnancy Medications and Allergies Medications and Allergies Prior Anesthetics Prior Anesthetics Related to Surgery : significant blood loss; respiratory compromise; positioning Related to Surgery : significant blood loss; respiratory compromise; positioning Problem Identification

Physical Examination:  General & Local examination  Should focus on evaluation of : Upper airwayUpper airway Respiratory systemRespiratory system Cardiovascular systemCardiovascular system other systems’ problems identified from the historyother systems’ problems identified from the history

Preoperative Laboratory Testing: only if indicated from the preoperative history and physical examination. "Routine or standing" pre operative tests should be discouraged -CBC anticipated significant blood loss, suspected hematological disorder (eg.anemia, thalassemia, SCD), or recent chemotherapy. -Electrolytes diuretics, chemotherapy, renal or adrenal disorders -ECG age >50 yrs,history of cardiac disease, hypertension, peripheral vascular disease, DM, renal, thyroid or metabolic disease. -Chest X-rays prior cardiothoracic procedures,COPD, asthma, a change in respiratory symptoms in the past six months. -Urine analysis DM, renal disease or recent UTI. -tests for different systems according to history and examination

Risk Assessment Components for evaluating perioperative risk: 1. 1.Preoperative patient's medical condition 2. 2.Extent of the surgical procedure 3. 3.Risk from the anesthetic technique

medical statusmortality ASA Inormal healthy patient without organic, biochemical, or psychiatric disease % ASA II mild systemic disease with no significant impact on daily activity e.g. mild diabetes, controlled hypertension, obesity. Unlikely to have an impact % ASA III severe systemic disease that limits activity e.g. angina, COPD, prior myocardial infarction Probable impact % ASA IV an incapacitating disease that is a constant threat to life e.g. CHF, unstable angina, renal failure,acute MI, respiratory failure requiring mechanical ventilation Major impact % ASA Vmoribund patient not expected to survive 24 hours e.g. ruptured aneurysm % ASA VI brain-dead patient whose organs are being harvested ASA Physical Status Classification System For emergent operations, you have to add the letter ‘E’ after the classification.

Surgical Risk Low surgical risk: Low surgical risk: –Endoscopy –Bronchoscopy –Cystoscopy –Dermatologic procedures –Breast biopsy –Opthalmologic procedures

Surgical Risk Intermediate surgical risk: Intermediate surgical risk: –Orthopedic surgery –Urologic surgery –Uncomplicated abdominal surgery –Uncomplicated head and neck

Surgical Risk High surgical risk: High surgical risk: –Emergency surgery –Cardiac procedures –Aortic or vascular surgery –Anticipated prolonged surgery  Large fluid shifts or blood loss  Ex: Whipple, spinal surgery

Preoperative Preparation Anesthetic indications: -Anxiolysis, sedation and amnesia. e.g. benzodiazepine(diazepam,lorazepam) -Analgesia e.g narcotics -Drying of airway secretions e.g atropine,glycopyrrolate,scopolamine -Reduction of anesthetic requirements,Facilitation of smooth induction -Patients at risk for GE reflux :ranitidine,metoclopramide, sodium citrate Surgical indications: -Antibiotic prophylaxis for infective endocarditis. -Prophylaxis against DVT for high risk patients : low-dose heparin or aspirin intermittent calf compression, or warfarin. Co-existing Disease indications: Some medications should be continued on the day of surgery e,g B blockers, thyroxine. Others are stopped e.g oral hypoglycemics and antidepressants. Steroids within the last six months may require supplemental steroids

Ingested materialMinimum fasting period (hr) Clear liquids2 Breast milk4 Infant formula6 Nonhuman milk6 Light meal (toast and clear liquids)6 Fasting Recommendations

Finally, we plan our anesthetic technique : 1.Local or Regional anesthesia 2. General anesthesia; with or without intubation. Spontaneous or controlled ventilation is used. 3. Combined regional with general anesthesia.