Abstract
The basis of general anesthesia is to establish the “triad” of hypnosis, muscle relaxation and suppression of sympathetic reflexes. This, together with manipulation of mechanical ventilation, fluid therapy, temperature and the circulation by the use of anesthetic and vasoactive drugs, can produce the required operating conditions for complex neurosurgery.
Most intravenous anesthetics decrease cerebral metabolism and blood flow and tend to have a cerebral protective effect and decrease intracranial pressure. The inhalational agents are all cerebral vasodilators that can be offset by the induction of hypocapnia through to hyperventilation. The overall effect on cerebral blood flow (CBF) depends on a balance between the concentration of the inhalational agent and the degree of hyperventilation.
Moderate hyperventilation reduces CBF and brain volume. Extreme hyperventilation may be associated with critical reduction in flow to compromised areas and focal ischemia. It is likely that barbiturates offer some protection for the brain against ischemia, but there is evidence that mild hypothermia has a cerebral protective effect that exceeds that of the barbiturates and which is out of proportion to the degree to which the cerebral metabolic rate is lowered.
The induction of general anesthesia depresses normal protective reflexes, and patients are at risk of aspiration of gastric contents. Those with raised intracranial pressure or who have suffered recent trauma causing vomiting are at particular risk.
Manipulation of the blood pressure may facilitate some procedures (e.g. the induction of hypotension during aneurysm surgery). Patients must be appropriately monitored and the risks of the failure of normal autoregulation of the cerebral circulation in patients with cerebral vasospasm must be considered. Careful monitoring control of the arterial pressure is also required where there is potential for cord ischemia.
A significant number of patients suffer moderate or severe pain after craniotomy. Morphine appears to be a safe analgesic and is more effective than codeine in postcraniotomy patients.
Management of the multiply injured patient must initially focus upon the ABC (airway, breathing and circulation) of basic life support.
Keywords
- Cerebral Blood Flow
- Cerebral Perfusion Pressure
- Laryngeal Mask Airway
- Cerebral Vasospasm
- Mild Hypothermia
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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References
Mayberg TS, Lam AM, Matta BF, Domino KB, Winn HR. Ketamine does not increase cerebral blood flow velocity or intracranial pressure during isoflurane/nitrous oxide anesthesia in patients undergoing craniotomy. Anesth Analg 1995;81:84–9.
Reinstrup P, Ryding E, Algotsson L, Messeter K, Asgeirsson B, Uski T. Distribution of cerebral blood flow during anesthesia with isoflurane or halothane in humans. Anesthesiology 1995;82:359–66.
Cho S, Fujigaki T, Uchiyama Y, Fukusaki M, Shibata O, Sumikawa K. Effects of sevoflurane with and without nitrous oxide on human cerebral circulation. Transcranial Doppler study. Anesthesiology 1996;85:755–60.
Algotsson L, Messeter K, Rosen I, Holmin T. Effects of nitrous oxide on cerebral haemodynamics and metabolism during isoflurane anesthesia in man. Acta Anaesthesiol Scand 1992;36:46–52.
Marsh ML, Dunlop BJ, Shapiro HM. Succinylcholine: intracranial pressure effects in neurosurgical patients. Anesth Analg 1980;59:550–1.
Stirt J, Grosslight K, Bedford R, Vollmer D. ‘Defasciculation’ with metocurine prevents succinylcholine-induced increases in intracranial pressure. Anesthesiology 1987;53:50–3.
Boyd AH, Eastwood NB, Parker CJ, Hunter JM. Comparison of the pharmacodynamics and pharmacokinetics of a cis-atracurium (51W89) or atracurium in critically ill patients undergoing mechanical ventilation in an intensive care unit. Br J Anaesth 1996;76:382–8.
Rosow C. Remifentanil: a unique opioid analgesic. Anesthesiology 1993;79:875–6.
Estilo A, Cottrell JE. Naloxone hypertension and ruptured cerebral aneurysm. Anesthesiology 1981;54:352.
Baskin DS, Hosobuchi Y. Naloxone reversal of ischemic neurological deficits in man. Lancet 1981;2:272.
Porter JM, Pidgeon C, Cunningham AJ. The sitting position in neurosurgery: a critical appraisal. Br J Anaesth 1999;82:117–28.
Kelleher A, Mackersie A. Cardiac arrest and resuscitation of a six month old achondroplastic baby undergoing neurosurgery in the prone position. Anesth Analg 1995;50:348–50.
Tung A. Indications for mechanical ventilation. Int Anesthesiol Clin 1997;35:1–17.
Ravussin P, de Tribolet N, Boulard G. Neuroanésthesie. Quelques aspects nouveaux. Neurochirurgie 1993;39:145–8.
Cheng MA, Theard MA, Tempelhof R. Intravenous agents and intraoperative neuroprotection. Beyond barbiturates. Crit Care Clin 1997;13:185–99.
Warner DS, Zhou JG, Ramani R, Todd MM. Reversible focal ischemia in the rat: effects of halothane, isoflurane, and methohexital anesthesia. J Cereb Blood Flow Metab 1991;11:794–802.
Stone JG, Young WL, Marans ZS, Solomon RA, Smith CR, Jamdar SC et al. Consequences of electroencephalographic-suppressive doses of propofol in conjunction with deep hypothermic circulatory arrest. Anesthesiology 1996;85:497–501.
Nemoto EM, Klementavicius R, Melick JA, Yonas H. Suppression of cerebral metabolic rate for oxygen (CMRO2) by mild hypothermia compared with thiopental. J Neurosurg Anesthesiol 1996;8:52–9.
Kouchoukos NT, Daily BB, Wareing TH, Murphy SF. Hypothermic circulatory arrest for cerebral protection during combined carotid and cardiac surgery in patients with bilateral carotid artery disease. Ann Surg 1994;21:699–705.
Fessatidis IT, Thomas VL, Shore DF, Sedgwick ME, Hunt RH, Weller RO. Brain damage after profoundly hypothermic circulatory arrest: correlations between neurophysiological and neuropathological findings. An experimental study in vertebrates. J Thorac Cardiovasc Surg 1993;106:32–41.
Stamford J. Beyond NMDA antagonists: looking to the future of neuroprotection. In: Stamford J, Strunin L, editors. Neuroprotection. London: Baillière Tindall, 1996;581–98.
Rowbotham DJ. Current management of postoperative nausea and vomiting. Br J Anaesth 1992;69:46S–59S.
Goldsack C, Scuplak SM, Smith M. A double-blind comparison of codeine and morphine for postoperative analgesia following intracranial surgery. Anesthesia 51:1996;1029–32.
Cashman J, McAnulty G. Nonsteroidal anti-inflammatory drugs in perisurgical pain management. Mechanisms of action and rationale for optimum use. Drugs 1995;49:51–70.
Leon JE, Bissonnette B. Transcranial Doppler sonography: nitrous oxide and cerebral blood flow velocity in children. Can J Anaesth 1991;38:974–9.
Clayton DG, O’Donoghue BM, Stevens JE, Savage PE. Cardiovascular response during cerebral angiography under general and local anesthesia. Anesthesia 1989;44:599–602.
Ferguson GG. The rationale for controlled hypotension. Int Anesthesiol Clin 1982;28:89–93.
Moss E, Dearden NM, Berridge JC. Effects of changes in mean arterial pressure on SjO2 during cerebral aneurysm surgery. Br J Anaesth 1995;75:527–30.
Bukht D, Lanford R. Airway obstruction after surgery in the neck. Anesthesia 1983;38(4):389–90.
Rosner MJ, Rosner SD, Johnson AH. Cerebral perfusion pressure: management protocol and clinical results. J Neurosurg 1995;83:949–62.
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Kraayenbrink, M., McAnulty, G. (2005). Neuroanesthesia. In: Moore, A.J., Newell, D.W. (eds) Neurosurgery. Springer Specialist Surgery Series. Springer, London. https://doi.org/10.1007/1-84628-051-6_4
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DOI: https://doi.org/10.1007/1-84628-051-6_4
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