Transcript 1Intro
INTRO TO ANESTHESIA SFC HILL Joint Special Operations Medical Training Center ANESTHESIA ANESTHESIA - Partial or complete loss of sensation with or with out loss of consciousness as result of disease, injury, or administration of an anesthetic agent, usually by injection or inhalation. Joint Special Operations Medical Training Center HISTORY OF ANESTHESIA PRIMITIVE TECHNIQUES • • • • • Club Strangulation Alcohol Mesmerism Plants Joint Special Operations Medical Training Center HISTORY OF ANESTHESIA INHALATION AGENTS • Nitrous Oxide • 1799 Davy • 1824 Hickman • 1844 Wells • Ether • 1842 Long • 1847 Snow • Modern Agents • • • • Halothane 1956 Enflurane 1972 Isoflurane 1981 Sevoflurane and Desflurane Joint Special Operations Medical Training Center HISTORY OF ANESTHESIA LOCAL/REGIONAL • • • • 1836 needle trochar 1844 hollow needle 1851 syringe 1884 Koller opthalmic anesthesia • 1885 Hallstead/Hall local/regional blocks • 1898 Bier spinal Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 1 (Amnesia): From induction of anesthesia to loss of conciousness (loss of eyelid reflex). Pain perception threshold is not lowered. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 2 (Delirium/Excitement): Characterized by uninhibited excitation. Pupils are dilated and eyes divergent. Agitation, delirium, irregular respiration, and breatholding are commonly seen. Potentially dangerous responses can occur during this stage including vomiting, laryngospasm, HTN, tachycardia, and uncontrolled movement. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 3 (Surgical Anesthesia): Central gaze,constricted pupils, and regular respirations. Target depth of anesthesia is sufficient when painful stimulation does not elicit somatic reflexes or deleterious autonomic reflexes. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 3 Plane 1 From the return of regular respirations to the cessation of REM. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 3 Plane 2 The Surgical Plane From the cessation of REM to the onset of paresis of the intercostal muscles. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 3 Plane 3 From the onset to the complete paralysis of the intercostal muscles. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 3 Plane 4 From the paralysis of the intercostal of this plane the patient will be apneic. muscles to the paralysis of the diaphragm - at the end Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW STAGES OF GENERAL ANESTHESIA • STAGE 4 (Impending Death/Overdose): Onset of apnea, dilated and nonreactive pupils, and hypotension to complete circulatory failure. Joint Special Operations Medical Training Center ANESTHESIA OVERVIEW COMPONENTS OF GENERAL ANESTHESIA • 1. Unconsciousness (Hypnosis) • 2. Analgesia (Areflexia) • 3. Muscle relaxation Joint Special Operations Medical Training Center