General AnesthesiaGeneral Anesthesia

Definition:Definition:

It is an altered physiologic state in It is an altered physiologic state in which, as a result of reversible drug which, as a result of reversible drug induced unconsciousness, noxious induced unconsciousness, noxious stimuli can neither be perceived nor stimuli can neither be perceived nor recalled.recalled.

Anesthesia ManagementAnesthesia Management

Preoperative management.Preoperative management. Intraoperative management.Intraoperative management. Postoperative managementPostoperative management

Preoperative managementPreoperative managementAim : Aim :

Is to ↓ perioperative morbidity and Is to ↓ perioperative morbidity and mortality.mortality.

Establishment of Rapport.Establishment of Rapport. Preoperative evaluation.Preoperative evaluation. Informed consentInformed consent Preoperative patient preparation.Preoperative patient preparation. Premedication.Premedication.

Pre operative visit.Pre operative visit.

It is considered negligence if It is considered negligence if anesthetic morbidity or mortality anesthetic morbidity or mortality occurs subsequently.occurs subsequently.

When it should be done?When it should be done?

The preoperative basic health The preoperative basic health assessment may be done anytime assessment may be done anytime within thirty days of the planned within thirty days of the planned procedure. procedure.

The purpose of a preoperative The purpose of a preoperative evaluationevaluation

Is not to "clear" patients for elective Is not to "clear" patients for elective surgery, but rather to evaluate and, surgery, but rather to evaluate and, if necessary, implement measures to if necessary, implement measures to prepare higher risk patients for prepare higher risk patients for surgery. surgery.

It can decrease the length of hospital It can decrease the length of hospital stay as well as minimize postponed stay as well as minimize postponed or cancelled surgeries. or cancelled surgeries.

Preoperative evaluationPreoperative evaluation

History.History. Examination.Examination. Investigation.Investigation. Risk assessment.Risk assessment.

1-HISTORY1-HISTORY

Current medical problems and other Current medical problems and other known problems.known problems.

Special habits.Special habits. Medical history.Medical history. History of previous anesthesia and History of previous anesthesia and

surgery.surgery. Family history.Family history. Review of organ systems.Review of organ systems. Last oral intake.Last oral intake.

2- PHYSICAL EXAMINATION2- PHYSICAL EXAMINATION

Vital signs.Vital signs. Weight and height.Weight and height. Airway.Airway. Heart and lung.Heart and lung. Nervous system.Nervous system. Other systems appearing affected by Other systems appearing affected by

history.history.

3- INVESTIGATIONS AND 3- INVESTIGATIONS AND LABORATORY EVALUATIONLABORATORY EVALUATION

It should be selective and It should be selective and individualized.individualized.

These tests are :These tests are :

11.Hematocrite or Hconcentration. .Hematocrite or Hconcentration. (1 mon)(1 mon)

22.S.glucose or s.creatinine or .S.glucose or s.creatinine or

BUN.(1 mon)BUN.(1 mon)

33.Chest x-rays.(6 months).Chest x-rays.(6 months)

44.ECG. (6 months).ECG. (6 months)

55.Liver function tests.(1 month).Liver function tests.(1 month)

66.Coagulation studies.(1 week).Coagulation studies.(1 week)

A urine pregnancy test should be A urine pregnancy test should be considered for women of childbearing considered for women of childbearing age.age.

Coagulation studies would be Coagulation studies would be indicated:indicated:

1.if the patient is receiving 1.if the patient is receiving

anticoagulant therapyanticoagulant therapy

2.family or personal history that 2.family or personal history that

suggests a bleeding disorder suggests a bleeding disorder 3.evidence of liver disease.3.evidence of liver disease.

SummarySummary of Recommended Preoperative Laboratory Tests of Recommended Preoperative Laboratory Tests Depending on the History and Physical FindingsDepending on the History and Physical Findings

Healthy patient <= 40 years Healthy patient <= 40 years Hemoglobin, urine screening for pregnancy Hemoglobin, urine screening for pregnancy in women of childbearing potential in women of childbearing potential

Healthy patient > 40 yearsHealthy patient > 40 yearsAdd ECG and blood glucose (age >=45 Add ECG and blood glucose (age >=45 years) years)

Cardiovascular disease.Cardiovascular disease.ECG, chest radiographs, hemoglobin, ECG, chest radiographs, hemoglobin, electrolytes, BUN, creatinine, glucose (age electrolytes, BUN, creatinine, glucose (age >=45 years or history of diabetes) >=45 years or history of diabetes)

Pulmonary disease.Pulmonary disease.Chest radiographs, hemoglobin, glucose Chest radiographs, hemoglobin, glucose (age >=45 years), ECG (age >40 years); (age >=45 years), ECG (age >40 years); provide patient with instructions for provide patient with instructions for incentive spirometry or deep-breathing incentive spirometry or deep-breathing exercises exercises

Abdominal or thoracic surgeryAbdominal or thoracic surgery Provide patient with instructions for Provide patient with instructions for incentive spirometry or deep-breathing incentive spirometry or deep-breathing exercisesexercises

MalnutritionMalnutritionLaboratory tests based on primary disease, Laboratory tests based on primary disease, plus albumin and lymphocyte count; if plus albumin and lymphocyte count; if malnutrition is severe, consider postponing malnutrition is severe, consider postponing surgery and providing preoperative surgery and providing preoperative supplementationsupplementation

4-RISK ASSESSMENT4-RISK ASSESSMENT

Def: Def: it is detection of pre-,intra-,and postoperative it is detection of pre-,intra-,and postoperative

risk factors which increase mortality and risk factors which increase mortality and morbidity. morbidity.

ASA physical status classification.ASA physical status classification. Other system assessment.Other system assessment. CVS CVS (Goldman's index).(Goldman's index). Respiratory assessment.Respiratory assessment. CNS assessment.CNS assessment. Renal and liver disease assessment.Renal and liver disease assessment.

ASA physical status classificationASA physical status classification

classclassdefinitiondefinitionPeriop. mortality Periop. mortality raterate

11

22

33

44

55

66

EE

A normal healthy personA normal healthy person

A patient with mild systemic A patient with mild systemic disease.disease.

Moderat systemic disease.Moderat systemic disease.

Severe systemic disease.Severe systemic disease.

A moribund patient.A moribund patient.

A brain dead patient.A brain dead patient.

If the procedure is an If the procedure is an emergency.emergency.

0.1%0.1%

0.3%0.3%

3%3%

15%15%

30%30%

Patients who warrant a second examination just Patients who warrant a second examination just before hospitalizationbefore hospitalization

Patients with cardiopulmonary Patients with cardiopulmonary disease.disease.

child with an upper respiratory tract child with an upper respiratory tract infection to assess the current status infection to assess the current status of the infection, to postpone the of the infection, to postpone the procedure because of persistent procedure because of persistent fever, wheezing or significant nasal fever, wheezing or significant nasal discharge.discharge.

Surgery-Related Predictors for Risk of Surgery-Related Predictors for Risk of

PerioperativePerioperative Cardiac Complications Cardiac Complications High riskHigh risk

Emergency surgery Emergency surgery Anticipated increased Anticipated increased blood loss. blood loss. Aortic or peripheral Aortic or peripheral vascular surgery vascular surgery

Intermediate riskIntermediate risk Abdominal or thoracic Abdominal or thoracic surgery surgery Head and neck Head and neck surgery surgery Carotid Carotid endarterectomy endarterectomy Orthopedic surgery Orthopedic surgery Prostate surgery Prostate surgery

Low riskLow risk Breast surgery Breast surgery Cataract surgery Cataract surgery Superficial surgery Superficial surgery Endoscopy Endoscopy

Patient-Related Predictors for Risk of Patient-Related Predictors for Risk of Perioperative Perioperative Cardiac ComplicationsCardiac Complications

Major clinical Major clinical predictorspredictors

Myocardial infarction Myocardial infarction <=6 weeks previously <=6 weeks previously Unstable angina Unstable angina Decompensated Decompensated congestive heart congestive heart failure failure Significant Significant arrhythmias (e.g., arrhythmias (e.g., causing hemodynamic causing hemodynamic instability) instability) Severe valvular Severe valvular disease (e.g., aortic or disease (e.g., aortic or mitral stenosis with mitral stenosis with valve area <1.0 cm2) valve area <1.0 cm2)

Intermediate clinical Intermediate clinical predictorspredictors

Mild angina pectoris Mild angina pectoris Myocardial infarction Myocardial infarction >6 weeks previously >6 weeks previously Compensated Compensated congestive heart congestive heart failure failure Diabetes mellitus Diabetes mellitus

Minor clinical Minor clinical predictorspredictors Advanced Advanced

age Abnormal age Abnormal electrocardiogram electrocardiogram Cardiac rhythm other Cardiac rhythm other than sinus than sinus Low functional Low functional capacity, capacity, history of stroke, history of stroke, uncontrolled uncontrolled hypertension hypertension

FIGURE 1.FIGURE 1.

Schematic figure for determining the need for Schematic figure for determining the need for preoperative cardiac testing on the basis of preoperative cardiac testing on the basis of the patient's clinical predictors and functional the patient's clinical predictors and functional status and the risk of the operative status and the risk of the operative procedure. (METs = metabolic equivalents of procedure. (METs = metabolic equivalents of oxygen consumption) Adapted with oxygen consumption) Adapted with permission from the American College of permission from the American College of Cardiology and the American Heart Cardiology and the American Heart Association. Guidelines for perioperative Association. Guidelines for perioperative cardiovascular evaluation for noncardiac cardiovascular evaluation for noncardiac surgery. surgery.

Preoperative Basic Health Assessment A complete preoperative basic health assessment includes:A complete preoperative basic health assessment includes:

Medical HistoryMedical History Indication for surgical procedureIndication for surgical procedure Allergies and intolerances to medications, anesthesia, or other Allergies and intolerances to medications, anesthesia, or other

agents (specify reaction type)agents (specify reaction type) Known medical problemsKnown medical problems Surgical historySurgical history Trauma (major)Trauma (major) Current medications (prescription, over-the-counter Current medications (prescription, over-the-counter

medications, herbal and dietary supplements, and illicit medications, herbal and dietary supplements, and illicit drugs)drugs)

Focused review of issues pertinent to the planned anesthesia Focused review of issues pertinent to the planned anesthesia and procedure:and procedure:

Current status of pertinent known medical problems Current status of pertinent known medical problems Cardiac status Cardiac status Pulmonary status Pulmonary status Functional status Functional status Hemostasis status (personal or family history of Hemostasis status (personal or family history of

abnormal bleeding) abnormal bleeding) Possibility of severe (symptomatic) anemiaPossibility of severe (symptomatic) anemia

Physical ExamPhysical Exam Weight and heightWeight and height Vital signs - blood pressure, pulse (rate and Vital signs - blood pressure, pulse (rate and

regularity), respiratory rateregularity), respiratory rate CardiacCardiac PulmonaryPulmonary Other pertinent examOther pertinent examElectrocardiogram (ECG)Electrocardiogram (ECG) Recommended for all patients age 55 and over, Recommended for all patients age 55 and over,

within one year prior to procedure. Also, ECGs are not within one year prior to procedure. Also, ECGs are not indicated, regardless of age, for those patients indicated, regardless of age, for those patients having cataract surgery.having cataract surgery.

Preoperative ECGs are not predictive of cardiac risk. Preoperative ECGs are not predictive of cardiac risk. [Conclusion grade II: See Conclusion Grading [Conclusion grade II: See Conclusion Grading Worksheet A - Annotation #4 (ECGs not Predictive) in Worksheet A - Annotation #4 (ECGs not Predictive) in the original guideline document].the original guideline document].

Patient EducationPatient Education Procedure-specificProcedure-specific General orientationGeneral orientation

A A history and physical examinationhistory and physical examination,, focusing focusing on risk factors for cardiac, pulmonary and on risk factors for cardiac, pulmonary and infectious complications, and a determination infectious complications, and a determination of a patient's functional capacity, are of a patient's functional capacity, are essential to any preoperative evaluation.essential to any preoperative evaluation.

In addition, the In addition, the type of surgerytype of surgery influences influences the overall perioperative risk and the need the overall perioperative risk and the need for further cardiac evaluation. for further cardiac evaluation.

Routine laboratory studiesRoutine laboratory studies are rarely helpful are rarely helpful except to monitor known disease states. except to monitor known disease states.

Clinical HighlightsClinical Highlights Provide a comprehensive preoperative basic health Provide a comprehensive preoperative basic health

assessment for all patients undergoing a diagnostic or assessment for all patients undergoing a diagnostic or therapeutic procedure as defined in the guideline. therapeutic procedure as defined in the guideline. ((Annotation #4Annotation #4) )

Most laboratory and diagnostic tests including Most laboratory and diagnostic tests including electrocardiograms (ECGs) are not necessary with routine electrocardiograms (ECGs) are not necessary with routine procedures unless a specific indication is present. procedures unless a specific indication is present. ((Annotation #6Annotation #6) )

ECGs are not indicated, regardless of age, for those ECGs are not indicated, regardless of age, for those patients having cataract surgery. patients having cataract surgery. (Annotation #4)(Annotation #4)

Patients on chronic beta-blocking therapy should continue Patients on chronic beta-blocking therapy should continue taking their beta-blocker medication up to and including the taking their beta-blocker medication up to and including the day of surgery. If beta-blocker therapy is stopped prior to day of surgery. If beta-blocker therapy is stopped prior to surgery, patients are at increased risk for complications surgery, patients are at increased risk for complications postoperatively. postoperatively. (Annotation #6(Annotation #6))