Overview of anesthesia and anesthetic choices
- Scott A Falk, MD
Scott A Falk, MD
- Assistant Professor of Clinical Anesthesiology and Critical Care
- University of Pennsylvania School of Medicine
- Lee A Fleisher, MD
Lee A Fleisher, MD
- Robert D Dripps Professor and Chair of Anesthesiology and Critical Care
- University of Pennsylvania School of Medicine
The state of "anesthesia" means different things to different individuals and is as much a philosophical state as a neuro-scientific one. While the definition of anesthesia itself, as the loss of "awareness," is rather vague, a pragmatic definition of anesthesia as the provision of a combination of amnesia, analgesia (pain control), and muscle relaxation to allow the performance of surgery or interventional procedures is more useful. Anesthesiologists are also responsible for physiologic homeostasis while the patient is in the anesthetized state providing for the safest and most comfortable perioperative experience possible.
Anesthesiologists and the anesthesia care team, including Certified Registered Nurse Anesthetists (CRNAs) and Anesthesia Assistants (AAs), work to provide a wide range of perioperative services including preoperative evaluation, intraoperative management, post-operative management, intensive care unit (ICU) care, and acute and chronic pain management. The consultant anesthesiologist will function to some degree in all these roles in each patient he/she takes care of, taking into consideration numerous factors when deciding on an anesthetic plan with the surgeon and patient.
This topic discusses an overview of anesthesia and anesthetic choices focusing on intraoperative management and the risks and benefits of anesthetic choices.
GOALS OF ANESTHESIA
The primary goal of anesthesia is the maintenance of physiologic homeostasis. This includes monitoring and treatment of cardiovascular, pulmonary, neurologic and renal functions and changes during the perioperative period to minimize adverse outcomes. Optimizing intraoperative physiology may help speed recovery and provide for perioperative organ system protection.
Amnesia — Amnesia refers to the lack of memory of the intraoperative and perioperative experience. It is reliably achieved by inducing a state of unconsciousness as a result of general anesthesia. A three year study including 87,361 patients found six patients reporting recall under general anesthesia (incidence 0.0068 percent, or 1 per 14,560) . This is the largest study to date looking at recall under general anesthesia. The rate of 1 in 14,560 is lower than the 0.1 and 0.9 percent rate generally reported in the literature. Previous studies have generally focused on specific patient populations at higher risk for recall, such as obstetric, trauma or cardiac patients, while this study included a wide range of procedures. Differences may also be due to observer or surveyor bias, and perceived differences in implicit versus explicit awareness.
- Pollard RJ, Coyle JP, Gilbert RL, Beck JE. Intraoperative awareness in a regional medical system: a review of 3 years' data. Anesthesiology 2007; 106:269.
- Ranta SO, Laurila R, Saario J, et al. Awareness with recall during general anesthesia: incidence and risk factors. Anesth Analg 1998; 86:1084.
- Rungreungvanich M, Thienthong S, Charuluxananan S, et al. Predictors of intra-operative recall of awareness: Thai Anesthesia Incidents Study (THAI Study): a case-control study. J Med Assoc Thai 2007; 90:1551.
- Jayr C, Thomas H, Rey A, et al. Postoperative pulmonary complications. Epidural analgesia using bupivacaine and opioids versus parenteral opioids. Anesthesiology 1993; 78:666.
- White PF, Kehlet H, Neal JM, et al. The role of the anesthesiologist in fast-track surgery: from multimodal analgesia to perioperative medical care. Anesth Analg 2007; 104:1380.
- Myles PS, Hendrata M, Bennett AM, et al. Postoperative nausea and vomiting. Propofol or thiopentone: does choice of induction agent affect outcome? Anaesth Intensive Care 1996; 24:355.
- Hug CC Jr, McLeskey CH, Nahrwold ML, et al. Hemodynamic effects of propofol: data from over 25,000 patients. Anesth Analg 1993; 77:S21.
- Chan CM, Mitchell AL, Shorr AF. Etomidate is associated with mortality and adrenal insufficiency in sepsis: a meta-analysis*. Crit Care Med 2012; 40:2945.
- Lundy JB, Slane ML, Frizzi JD. Acute adrenal insufficiency after a single dose of etomidate. J Intensive Care Med 2007; 22:111.
- Jabre P, Combes X, Lapostolle F, et al. Etomidate versus ketamine for rapid sequence intubation in acutely ill patients: a multicentre randomised controlled trial. Lancet 2009; 374:293.
- Komatsu R, You J, Mascha EJ, et al. Anesthetic induction with etomidate, rather than propofol, is associated with increased 30-day mortality and cardiovascular morbidity after noncardiac surgery. Anesth Analg 2013; 117:1329.
- Reich DL, Silvay G. Ketamine: an update on the first twenty-five years of clinical experience. Can J Anaesth 1989; 36:186.
- Bunker JP. Final Report of the National Halothane Study. Anesthesiology 1968; 29:231.
- Myles PS, Leslie K, Chan MT, et al. The safety of addition of nitrous oxide to general anaesthesia in at-risk patients having major non-cardiac surgery (ENIGMA-II): a randomised, single-blind trial. Lancet 2014; 384:1446.
- Turan A, Mascha EJ, You J, et al. The association between nitrous oxide and postoperative mortality and morbidity after noncardiac surgery. Anesth Analg 2013; 116:1026.
- Leslie K, Myles P, Devereaux PJ, et al. Nitrous oxide and serious morbidity and mortality in the POISE trial. Anesth Analg 2013; 116:1034.
- Fleischmann E, Lenhardt R, Kurz A, et al. Nitrous oxide and risk of surgical wound infection: a randomised trial. Lancet 2005; 366:1101.
- Gan TJ, Diemunsch P, Habib AS, et al. Consensus guidelines for the management of postoperative nausea and vomiting. Anesth Analg 2014; 118:85.
- Sanders RD, Weimann J, Maze M. Biologic effects of nitrous oxide: a mechanistic and toxicologic review. Anesthesiology 2008; 109:707.
- Flippo TS, Holder WD Jr. Neurologic degeneration associated with nitrous oxide anesthesia in patients with vitamin B12 deficiency. Arch Surg 1993; 128:1391.
- Baum VC. When nitrous oxide is no laughing matter: nitrous oxide and pediatric anesthesia. Paediatr Anaesth 2007; 17:824.
- Röhm KD, Piper SN, Suttner S, et al. Early recovery, cognitive function and costs of a desflurane inhalational vs. a total intravenous anaesthesia regimen in long-term surgery. Acta Anaesthesiol Scand 2006; 50:14.
- Maurer SG, Chen AL, Hiebert R, et al. Comparison of outcomes of using spinal versus general anesthesia in total hip arthroplasty. Am J Orthop (Belle Mead NJ) 2007; 36:E101.
- McKenzie PJ, Wishart HY, Gray I, Smith G. Effects of anaesthetic technique on deep vein thrombosis. A comparison of subarachnoid and general anaesthesia. Br J Anaesth 1985; 57:853.
- Naesh O, Hindberg I, Friis J, Christiansen C. General versus regional anaesthesia and platelet aggregation in minor surgery. Eur J Anaesthesiol 1994; 11:169.
- Parker SD, Breslow MJ, Frank SM, et al. Catecholamine and cortisol responses to lower extremity revascularization: correlation with outcome variables. Perioperative Ischemia Randomized Anesthesia Trial Study Group. Crit Care Med 1995; 23:1954.
- Urwin SC, Parker MJ, Griffiths R. General versus regional anaesthesia for hip fracture surgery: a meta-analysis of randomized trials. Br J Anaesth 2000; 84:450.
- Rodgers A, Walker N, Schug S, et al. Reduction of postoperative mortality and morbidity with epidural or spinal anaesthesia: results from overview of randomised trials. BMJ 2000; 321:1493.
- Park WY, Thompson JS, Lee KK. Effect of epidural anesthesia and analgesia on perioperative outcome: a randomized, controlled Veterans Affairs cooperative study. Ann Surg 2001; 234:560.
- Stride PC, Cooper GM. Dural taps revisited. A 20-year survey from Birmingham Maternity Hospital. Anaesthesia 1993; 48:247.
- Vallejo MC, Mandell GL, Sabo DP, Ramanathan S. Postdural puncture headache: a randomized comparison of five spinal needles in obstetric patients. Anesth Analg 2000; 91:916.
- Moen V, Dahlgren N, Irestedt L. Severe neurological complications after central neuraxial blockades in Sweden 1990-1999. Anesthesiology 2004; 101:950.
- Horlocker TT, Wedel DJ, Schroeder DR, et al. Preoperative antiplatelet therapy does not increase the risk of spinal hematoma associated with regional anesthesia. Anesth Analg 1995; 80:303.
- Litz RJ, Gottschlich B, Stehr SN. Spinal epidural hematoma after spinal anesthesia in a patient treated with clopidogrel and enoxaparin. Anesthesiology 2004; 101:1467.
- Tam NL, Pac-Soo C, Pretorius PM. Epidural haematoma after a combined spinal-epidural anaesthetic in a patient treated with clopidogrel and dalteparin. Br J Anaesth 2006; 96:262.
- Horlocker TT, Wedel DJ, Benzon H, et al. Regional anesthesia in the anticoagulated patient: defining the risks (the second ASRA Consensus Conference on Neuraxial Anesthesia and Anticoagulation). Reg Anesth Pain Med 2003; 28:172.
- Wiegel M, Gottschaldt U, Hennebach R, et al. Complications and adverse effects associated with continuous peripheral nerve blocks in orthopedic patients. Anesth Analg 2007; 104:1578.
- van Zundert A, Helmstädter A, Goerig M, Mortier E. Centennial of intravenous regional anesthesia. Bier's Block (1908-2008). Reg Anesth Pain Med 2008; 33:483.
- Guay J. Adverse events associated with intravenous regional anesthesia (Bier block): a systematic review of complications. J Clin Anesth 2009; 21:585.
- Brown EM, McGriff JT, Malinowski RW. Intravenous regional anaesthesia (Bier block): review of 20 years' experience. Can J Anaesth 1989; 36:307.
- American Society of Anesthesiologists Task Force on Sedation and Analgesia by Non-Anesthesiologists. Practice guidelines for sedation and analgesia by non-anesthesiologists. Anesthesiology 2002; 96:1004.
- Bhananker SM, Posner KL, Cheney FW, et al. Injury and liability associated with monitored anesthesia care: a closed claims analysis. Anesthesiology 2006; 104:228.
- Botney R. Improving patient safety in anesthesia: a success story? Int J Radiat Oncol Biol Phys 2008; 71:S182.
- Fleisher LA, Pasternak LR, Herbert R, Anderson GF. Inpatient hospital admission and death after outpatient surgery in elderly patients: importance of patient and system characteristics and location of care. Arch Surg 2004; 139:67.
- Cohen MM, Duncan PG, Tate RB. Does anesthesia contribute to operative mortality? JAMA 1988; 260:2859.
- Lanier WL. A three-decade perspective on anesthesia safety. Am Surg 2006; 72:985.
- Wolters U, Wolf T, Stützer H, Schröder T. ASA classification and perioperative variables as predictors of postoperative outcome. Br J Anaesth 1996; 77:217.
- Fleisher LA, Beckman JA, Brown KA, et al. 2009 ACCF/AHA focused update on perioperative beta blockade incorporated into the ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: a report of the American college of cardiology foundation/American heart association task force on practice guidelines. Circulation 2009; 120:e169.
- Rose DK, Cohen MM. The airway: problems and predictions in 18,500 patients. Can J Anaesth 1994; 41:372.
- Burkle CM, Walsh MT, Harrison BA, et al. Airway management after failure to intubate by direct laryngoscopy: outcomes in a large teaching hospital. Can J Anaesth 2005; 52:634.
- Biro P, Seifert B, Pasch T. Complaints of sore throat after tracheal intubation: a prospective evaluation. Eur J Anaesthesiol 2005; 22:307.
- Charuluxananan S, Punjasawadwong Y, Suraseranivongse S, et al. The Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes: II. Anesthetic profiles and adverse events. J Med Assoc Thai 2005; 88 Suppl 7:S14.
- Suraseranivongse S, Valairucha S, Chanchayanon T, et al. The Thai Anesthesia Incidents Study (THAI Study) of pulmonary aspiration: a qualitative analysis. J Med Assoc Thai 2005; 88 Suppl 7:S76.
- Brimacombe JR, Berry A. The incidence of aspiration associated with the laryngeal mask airway: a meta-analysis of published literature. J Clin Anesth 1995; 7:297.
- Nuttall GA, Barnett MR, Smith RL 2nd, et al. Establishing intravenous access: a study of local anesthetic efficacy. Anesth Analg 1993; 77:950.
- Harvey S, Young D, Brampton W, et al. Pulmonary artery catheters for adult patients in intensive care. Cochrane Database Syst Rev 2006; :CD003408.
- Polanczyk CA, Rohde LE, Goldman L, et al. Right heart catheterization and cardiac complications in patients undergoing noncardiac surgery: an observational study. JAMA 2001; 286:309.
- Sandham JD, Hull RD, Brant RF, et al. A randomized, controlled trial of the use of pulmonary-artery catheters in high-risk surgical patients. N Engl J Med 2003; 348:5.
- GOALS OF ANESTHESIA
- Neuromuscular blockade
- TYPES OF ANESTHESIA
- General anesthesia
- - Induction
- - Maintenance
- - Emergence
- Neuraxial anesthesia
- - Spinal anesthesia
- - Epidural anesthesia and analgesia
- - Complications
- Peripheral nerve block
- Intravenous regional block
- Monitored anesthesia care
- PREOPERATIVE RISK ASSESSMENT
- Risk classification systems
- COMMON ANESTHESIA PROCEDURES
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS