thiopental and Intracranial-Aneurysm

Although hypothermia and barbiturates improve neurologic outcomes in animal temporary focal ischemia models, the clinical efficacy of these interventions during temporary occlusion of the cerebral vasculature during intracranial aneurysm surgery (temporary clipping) is not established.. A post hoc analysis of patients from the Intraoperative Hypothermia for Aneurysm Surgery Trial who underwent temporary clipping was performed. Univariate and multivariate logistic regression methods were used to test for associations between hypothermia, supplemental protective drug, and short- (24-h) and long-term (3-month) neurologic outcomes. An odds ratio more than 1 denotes better outcome.. Patients undergoing temporary clipping (n = 441) were assigned to intraoperative hypothermia (33.3 degrees +/- 0.8 degrees C, n = 208) or normothermia (36.7 degrees +/- 0.5 degrees C, n = 233), with 178 patients also receiving supplemental protective drug (thiopental or etomidate) during temporary clipping. Three months after surgery, 278 patients (63%) had good outcome (Glasgow Outcome Score = 1). Neither hypothermia (P = 0.847; odds ratio = 1.043, 95% CI = 0.678-1.606) nor supplemental protective drug (P = 0.835; odds ratio = 1.048, 95% CI = 0.674-1.631) were associated with 3-month Glasgow Outcome Score. The effect of supplemental protective drug did not significantly vary with temperature. The effects of hypothermia and protective drug did not significantly vary with temporary clip duration. Similar findings were made for 24-h neurologic status and 3-month Neuropsychological Composite Score.. In the Intraoperative Hypothermia for Aneurysm Surgery Trial, neither systemic hypothermia nor supplemental protective drug affected short- or long-term neurologic outcomes of patients undergoing temporary clipping.

Topics: Aged; Anesthesia, General; Aneurysm, Ruptured; Body Temperature; Double-Blind Method; Female; Glasgow Outcome Scale; Humans; Hypnotics and Sedatives; Hypothermia, Induced; Intracranial Aneurysm; Logistic Models; Male; Middle Aged; Nervous System Diseases; Neuropsychological Tests; Neurosurgical Procedures; Postoperative Complications; Prospective Studies; Protective Agents; Thiopental; Treatment Outcome

55 patients (age 45-63 years old) scheduled for elective brain artery anaeurysm repair operation were randomly divided into two groups: thiopental, atracurium besilate and fentanyl group (group I; n= 27) and propofol, vecuronium bromide and fentanyl in a continuous intravenous administration group (group II; n=28). In group II little changes of arterial blood pressure during the operation were observed. Also the mean time for patient's awaiking was significantly shorter which allowed effective postoperative evaluation of neurological status. In group II only 1 patient required administration of urapidil and in group I 11 ( 40.7%) of patients required lowering blood pressure treatment. There were 7 cases of intra-operative aneurysm ruptures and 5 cases of brain artery embolism not significantly associated with anaesthesia given. It is of a high importance to maintain intraoperatively normal blood pressure, normal blood oxigenation, normal fluid administration and normal blood carbon dioxide levels.

Topics: Anesthesia, General; Anesthetics, Intravenous; Carbon Dioxide; Female; Fentanyl; Humans; Hydrotherapy; Hypertension; Intracranial Aneurysm; Intraoperative Care; Male; Middle Aged; Neurologic Examination; Neuromuscular Nondepolarizing Agents; Oxygen; Postoperative Care; Propofol; Thiopental; Vecuronium Bromide

Thiopental produces cerebral metabolic depression and cerebral vasoconstriction. However, the effect of thiopental on brain tissue oxygen pressure (PO2), carbon dioxide pressure, and pH is not known. In a prospective study, we measured brain tissue gases and pH during thiopental or desflurane treatment that was administered for brain protection during brain artery occlusion.. After institutional review board approval, 20 patients undergoing craniotomies for cerebrovascular surgery were tested; 10 were randomized to receive thiopental and 10 to receive desflurane. After each craniotomy, a Neurotrend probe (Diametrics Medical, Minneapolis, MN) was inserted to measure tissue PO2, carbon dioxide pressure, and pH in a tissue region at risk to develop ischemia during temporary brain artery occlusion. Thiopental or desflurane was administered to produce burst suppression of electroencephalography, and then temporary artery occlusion was performed during aneurysm or extracerebral-to-intracerebral bypass surgery.. Thiopental produced no change in tissue gases or pH, but temporary artery clipping in thiopental-treated patients decreased PO2 30% (P < 0.05). Desflurane increased PO2 70% (P < 0.05), and tissue oxygenation remained elevated during temporary artery occlusion. Tissue pH did not decrease in either group during temporary brain artery occlusion.. Thiopental has a metabolically neutral effect on brain tissue gases and pH, even though it is known to decrease cerebral oxygen consumption. The metabolic depressant and vasodilator effects of desflurane enhance tissue oxygenation and attenuate tissue PO2 reductions produced by artery occlusion. Both thiopental and desflurane inhibit ischemic lactic acidosis and decreases in pH.

Topics: Acid-Base Equilibrium; Anesthetics, Inhalation; Brain; Brain Ischemia; Cerebral Revascularization; Craniotomy; Desflurane; Energy Metabolism; Humans; Intracranial Aneurysm; Isoflurane; Monitoring, Intraoperative; Neuroprotective Agents; Oxygen Consumption; Thiopental; Vasodilation

Some cerebral artery aneurysms require cardiopulmonary bypass and deep hypothermic circulatory arrest to be clipped safely. During bypass these neurosurgical patients often are given large doses of thiopental in the hope that additional cerebral protection will be provided. However, thiopental loading during bypass has been associated with subsequent cardiac dysfunction in patients with heart disease. This study was undertaken to determine how patients without concomitant heart disease would respond to thiopental loading.. Twenty-four neurosurgical patients with giant cerebral aneurysms and little or no cardiac disease were anesthetized with fentanyl, nitrous oxide, and isoflurane. Thiopental was titrated to achieve electroencephalographic burst-suppression before bypass, and the infusion was continued until after separation. Prebypass hemodynamic and echocardiographic measurements were obtained during a stable baseline and 15 min after thiopental loading began. They were repeated after bypass.. Prebypass thiopental loading increased heart rate from 61 +/- 11 to 72 +/- 13 beats/min and decreased stroke volume from 43 +/- 10 to 38 +/- 8 ml.beat-1.m-2, but arterial and filling pressures, vascular resistance, cardiac index, and ejection fraction remained the same. Before bypass, thiopental plasma concentration measured 28 +/- 8 micrograms/ml. Loading continued for 2-3 h until after bypass was terminated, and the overall infusion rate was 18 +/- 5 mg.kg-1.h-1. All patients were easily separated from bypass without inotropic support. Following bypass, vascular resistance was decreased; heart rate, filling pressures, and cardiac index were increased; stroke volume had returned to its baseline; and ejection fraction was unchanged.. It was concluded that if preoperative ventricular function is good, thiopental loading to electroencephalographic burst-suppression causes negligible cardiac impairment and does not impede separation from cardiopulmonary bypass.

Topics: Adult; Anesthesia; Blood Circulation; Cardiopulmonary Bypass; Dose-Response Relationship, Drug; Electroencephalography; Female; Heart; Hemodynamics; Humans; Hypothermia, Induced; Intracranial Aneurysm; Male; Middle Aged; Thiopental

ANTERIOR COMMUNICATING ARTERY aneurysms are complex lesions for which surgical success requires extensive preoperative and intraoperative planning. Adherence to the tenets of aneurysm surgery, including vascular control and preservation of perforating arteries, is essential for their exclusion from the circulation.

Topics: Brain; Cerebrovascular Circulation; Constriction; Humans; Intracranial Aneurysm; Neurosurgical Procedures; Thiopental

We report a case of carotid endarterectomy and clipping of an ipsilateral internal carotid artery aneurysm in a patient with complete contralateral carotid stenosis. The patient developed an ischaemic electroencephalographic (EEG) tracing on temporary carotid clamping and bypass shunt was contraindicated. We used thiopentone titrated to EEG burst suppression for pharmacological cerebral protection during the subsequent prolonged carotid clamp necessary for carotid endarterectomy. We review the use of thiopentone for this purpose, in particular the evidence for efficacy, mechanism of action and optimal dosage and timing of administration.

Topics: Brain Ischemia; Carotid Artery, Internal; Carotid Stenosis; Constriction; Electroencephalography; Endarterectomy, Carotid; Female; Humans; Hypnotics and Sedatives; Intracranial Aneurysm; Intraoperative Complications; Middle Aged; Neuroprotective Agents; Thiopental

Thiopental intravenous injections before temporary clipping and mild hypothermia have protective effects in the setting of cerebral ischemia, and are used clinically in some centers. However, it is not known whether mild hypothermia affects thiopental-induced electroencephalogram (EEG) burst suppression. In this study, the authors compared the onset and duration of EEG suppression by thiopental in normothermic (n=10) and mildly hypothermic (n=10) patients undergoing cerebral aneurysm surgery. Spectral analysis was used to compare the prethiopentonal continuous EEG patterns in normothermic and mild hypothermic patients. The patients' body temperatures were controlled by a circulating water mattress and intravenous fluids (normothermia = 36.4+/-0.1 degrees C, mild hypothermia = 33.3+/-0.1 degrees C). Immediately before temporary clipping, thiopental sodium (5 mg/kg) was administered intravenously. Onset time (the amount of time from thiopental injection to the first complete EEG suppression), duration of suppression (the amount of time from the first complete EEG suppression to recovery on continuous EEG from burst suppression), and maximum duration of isoelectric EEG (the longest time interval between two bursts during burst suppression) were measured. Onset time was shortened (25.8+/-1.4 versus 43.5+/-5.6 seconds), and duration of suppression (531.0+/-56.6 versus 165.0+/-16.9 seconds) and the maximum duration of isoelectric EEG (47.7+/-5.8 versus 22.8+/-2.0 seconds) were prolonged in the patients with mild hypothermia. In two normothermic patients, the standard dose of thiopental did not produce burst suppression, but only a mild decrease in spectral edge frequency. The authors concluded that the effects of mild hypothermia on thiopental-induced EEG suppression are not simply additive, but synergistic.

Topics: Adult; Beds; Body Temperature; Cerebrovascular Circulation; Electroencephalography; Female; Fluid Therapy; GABA Modulators; Humans; Hypothermia, Induced; Injections, Intravenous; Intracranial Aneurysm; Male; Middle Aged; Neuroprotective Agents; Signal Processing, Computer-Assisted; Thiopental; Time Factors

Topics: Anesthetics; Arterial Occlusive Diseases; Carotid Artery Diseases; Fentanyl; Humans; Hypertension; Intracranial Aneurysm; Male; Middle Aged; Phenylephrine; Sufentanil; Thiopental

The anaesthetic management of a patient whose giant cerebral aneurysm was clipped is described. Profound hypothermia and thiopentone were used to provide cerebral protection during circulatory arrest. Atracurium was used to provide muscle relaxation; the level of neuromuscular block and plasma concentrations of atracurium and laudanosine were measured.

Topics: Adult; Anesthesia, General; Atracurium; Female; Fentanyl; Heart Arrest, Induced; Humans; Hypothermia, Induced; Intracranial Aneurysm; Isoflurane; Isoquinolines; Thiopental

In a review of 147 patients with intracranial aneurysms surgically treated by one surgeon (FAD) between 1980 and 1987, 36 selected patients received intraoperative barbiturate protection with sodium thiopental during temporary arterial occlusion. Thiopental doses of 5 to 15 mg/kg were used. Twenty-nine of 36 (81%) had ruptured aneurysms. Occlusion times ranged from 3 to 93 minutes, with a mean of 16.2 minutes. Seven patients had new neurological deficit in the immediate postoperative period, but in only two did these persist. Twenty-one patients (72%) with subarachnoid hemorrhage and 6 with incidental aneurysms made a good recovery. Of the 9 patients with significant permanent deficit, all but 2 were related to either the severity of the initial hemorrhage or to delayed vasospasm. In only one instance might temporary arterial occlusion have led to permanent neurological sequelae. Temporary arterial occlusion with barbiturate protection is a safe technique. For aneurysms that are more surgically complex, it allows for complete dissection of the aneurysm neck and identification and preservation of the surrounding vascular anatomy, while reducing the risk of intraoperative rupture and postoperative stroke.

Topics: Adult; Aged; Cerebral Arteries; Cerebral Infarction; Constriction; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Neurosurgery; Radiography; Subarachnoid Hemorrhage; Thiopental; Time Factors

The effects and indications of barbiturate therapy for brain protection, and prevention and reduction of the intracranial hypertension were investigated using an ultrashort acting barbiturate, thiamylal, in sixteen cases with intracranial lesions. Final outcome of the treatment revealed 8 good recoveries which were actively administered thiamylal during operation or immediately after. On the other hand, four cases, whose intracranial pressures (ICPS) of over 40 mmHg could not be controlled suffered brain death. Barbiturate therapy was not effective for brain protection of primary damaged lesions. It is concluded that barbiturate therapy may provide a satisfactory reduction of the intracranial hypertension in cases during the early postoperative stage or of under 40 mmHg initial ICP.

Topics: Adolescent; Adult; Aged; Brain Edema; Brain Injuries; Brain Neoplasms; Cerebral Hemorrhage; Child, Preschool; Female; Humans; Intracranial Aneurysm; Intracranial Arteriovenous Malformations; Male; Middle Aged; Postoperative Complications; Pseudotumor Cerebri; Thiamylal; Thiopental

A well integrated and coordinated team between Neurosurgeon and Anesthetist is necessary to achieved the best results in aneurysm surgery. Drugs-induced hypotension, cerebral metabolic depressant drugs (such as thiopentone), new anaesthetic drugs, hypocapnia are the anaesthetic techniques of choice in intracranial aneurysm surgery.

Topics: Anesthesia, General; Carbon Dioxide; Cerebrovascular Circulation; Dexamethasone; Humans; Hypotension, Controlled; Intracranial Aneurysm; Mannitol; Preanesthetic Medication; Thiopental

A review of 45 cerebral vasospasm cases for cerebral infarct under computer tomography (CT) scanner and based on activities of daily living (ADL) resulted in the finding that, of 19 cases with vasospasm of "diffuse, severe" grade, 14 cases were rated "poor (disabled)" to "dead": CT-diagnosed cerebral infarct was found in 4 out of 6 cases. From this, it was believed that indication for B-therapy was clinically significant vasospasm (diffuse, severe), which falls under the clinical grade of III or IV by Hunt and Kosnik without considering such incidental condition as severe vasospasm. After B-therapy, 45% showed ADL of at least "fair". CT-diagnosed cerebral infarct was found in 4 out of 10 cases. None died from complications as a result of B-therapy. The examination of ineffectual cases pointed to the importance of the first choice application of B-therapy, the continuation of the therapy as long as vasospasm continues, and the sustenance of cerebral perfusion pressure by the use of vasopressor (Dopamine) to offset the hypotensive effect of barbiturate. With these points of care exercised, the B-therapy is believed to achieve good results.

Topics: Adult; Aged; Anesthesia, Endotracheal; Cerebral Infarction; Dopamine; Drug Therapy, Combination; Female; Humans; Hypotension; Intracranial Aneurysm; Ischemic Attack, Transient; Male; Middle Aged; Thiopental

In this study we report our clinical experience with supplementary thiopental loading, based on 30 patients undergoing surgery for intracranial aneurysm after a recent episode of subarachnoid haemorrhage. As standard procedure we used pentobarbitone induction, pancuronium relaxation, endotracheal intubation, maintenance with halothane 0.5%, N2O 66% in oxygen, fentanyl, and moderate hypocapnia. A thiopental load of up to 20 mg X kg-1 was supplied while the aneurysm was approached. Satisfactory and well-controlled hypotension was obtained in five cases after thiopental alone, and after thiopental and sodium nitroprusside (SNP) (means +/- s.d.) 1.3 +/- 0.9 microgram X kg-1 X min-1 in the remaining 25 patients. No ECG sign of myocardial ischaemia was observed. One disadvantage was a prolonged recovery period, which in some cases necessitated controlled ventilation for some hours. We conclude that thiopental loading can be used safely as a supplement to neuroanaesthesia for aneurysm surgery.

Topics: Adult; Anesthesia, General; Blood Pressure; Consciousness; Female; Heart Rate; Humans; Hypotension, Controlled; Intracranial Aneurysm; Male; Middle Aged; Nitroprusside; Pulmonary Gas Exchange; Rupture, Spontaneous; Subarachnoid Hemorrhage; Thiopental; Time Factors

Topics: Adult; Anesthesia, General; Female; Hemodilution; Humans; Hyperthermia, Induced; Infusions, Parenteral; Intracranial Aneurysm; Male; Middle Aged; Thiopental

Forty patients undergoing intracranial aneurysm clipping were operated on under either barbiturate anesthesia (in 22) or enflurane anesthesia (in 18). Cardiac output, arterial and mixed venous oxygen tension, and arterial, right atrial, pulmonary arterial, and pulmonary artery wedge pressures were measured. Cardiac index, intrapulmonary shunt fraction, and pulmonary vascular resistance were calculated. Hypotension to 60, 50, and 40 torr was induced with sodium nitroprusside. There was a decrease in shunt fraction with the induction of anesthesia in both groups. During induced hypotension there was a slight increase in shunting in the enflurane group. The venous oxygen content was significantly less than control values during the hypotensive period in both groups as a result of decreased cardiac output. The arteriovenous oxygen difference was significantly greater than control at the post-mannitol and hypotensive periods. Pulmonary vascular resistance was significantly less in the enflurane group.

Topics: Adolescent; Adult; Aged; Anesthesia, Intravenous; Cardiac Output; Enflurane; Humans; Hypotension, Controlled; Intracranial Aneurysm; Middle Aged; Morphine; Nitroprusside; Nitrous Oxide; Oxygen; Pulmonary Circulation; Thiopental

Twenty patients undergoing intracranial aneurysm clipping were anesthetized with doses of thiopental sufficient to produce electroencephalographic burst suppression, nitrous oxide, oxygen, and morphine sulfate. Diuresis was induced with a combination of furosemide and mannitol. The cardiovascular effects of this anesthetic technique were studied. The central venous, pulmonary artery, pulmonary artery wedge, and systemic arterial blood pressures and the cardiac output were determined. The cardiac index and the systemic and pulmonary vascular resistance were calculated. The systemic blood pressure remained unchanged throughout the procedure except during the period of induced hypotension. The cardiac index decreased on the average from 3.3 during the control period to 2.15 litres/minute/m2 after the induction of anesthesia and diuresis (P less than 0.05). During sodium nitroprusside-induced hypotension, there was a further decrease in the cardiac index to 1.81 litres/minute/m2 (P less than 0.05). Changes in the cardiac index were associated with a significant decrease in the central venous and pulmonary artery wedge pressures from 2.5 to 0.1 and 5.9 to 0.2 torr, respectively) and an increased systemic vascular resistance. Cardiovascular performance recovered quickly after termination of the induced hypotension and remained stable in the postoperative period. This anesthetic technique seems to be useful in the surgical repair of intracranial aneurysms.

Topics: Adolescent; Adult; Aged; Anesthesia, Intravenous; Blood Pressure; Cardiac Output; Humans; Intracranial Aneurysm; Middle Aged; Outcome and Process Assessment, Health Care; Rupture, Spontaneous; Thiopental; Vascular Resistance

The cardiovascular effects of large dose thiopental anesthesia and induced hypotension were examined in 22 patients undergoing clipping of ruptured intracranial aneurysms. Eleven patients operated on within 4 days of the initial bleed (early group) were compared with those operated on more than 10 days after the bleed (late group). Systemic and pulmonary arterial pressures, central venous pressure, and cardiac output were measured. The cardiac index and the systemic and pulmonary vascular resistance were calculated. Before the induction of anesthesia, the cardiac index was 4.00 +/- 0.3 litres/minute/m2 in the early group compared with 2.89 +/- 0.23 litres/minute/m2 in the late group (P less than 0.05). Five and 10 minutes after the administration of mannitol (1 g/kg) and at an induced hypotensive level of 60 torr, the cardiac index remained significantly higher in the early group (P less than 0.05). There was no significant difference in the mean arterial blood pressure between the groups. Systemic vascular resistance was significantly higher in the late group during the postinduction and the pre-mannitol infusion periods and at induced hypotensive levels of 50 and 40 torr. Central venous pressure was significantly higher in the early group only at the preanesthesia (control) measurement. There was no significant difference between the groups in the pulmonary artery wedge pressure or the pulmonary vascular resistance.

Topics: Adolescent; Adult; Aged; Anesthesia, General; Blood Pressure; Female; Hemodynamics; Humans; Hypotension, Controlled; Intracranial Aneurysm; Intraoperative Period; Male; Middle Aged; Nitrous Oxide; Oxygen; Thiopental

The postoperative intracranial pressure (ICP) in 36 patients operated on for cerebral aneurysm following subarachnoid hemorrhage was studied. Not only was the baseline ICP significantly lower in patients whose outcome was assessed as "good" as compared with those patients with a worse outcome at 1 month after surgery, but also the height of the plateau waves and B-waves was significantly less in the patients who did well. The baseline ICP and the height of the B-wave formation were unrelated to the position of the aneurysm. Plateau waves were marginally significantly higher in aneurysms of the anterior communicating artery complex. Neither preoperative hypertension nor the use of antifibrinolytic agents made any difference to postoperative ICP. In patients with cerebral arterial vasospasm found preoperatively on the angiograms, the ICP tended to be lower in the postoperative period than in those without spasm.

Topics: Cerebral Arteries; Female; Humans; Intracranial Aneurysm; Intracranial Pressure; Male; Postoperative Complications; Postoperative Period; Subarachnoid Hemorrhage; Systole; Thiopental

Two patients who underwent surgery for cerebral aneurysms are presented. In the first case 31 g thiopentone were given postoperatively over 20 h after the patient had already been comatose for many hours. Such high doses raise considerable problems in patient management. In the second case a loading dose of 50 mg/kg thiopentone was given prophylactically to a patient undergoing cerebral aneurysm surgery beginning at the induction of anaesthesia and before surface cooling was begun. Cerebral activity was monitored continuously with a cerebral function monitor (CFM). There was no significant cardiovascular depression, little delay in postoperative recovery and no permanent neurological sequelae. In cerebral aneurysm surgery, cerebral oedema following cerebral ischaemia, either associated with vasospasm or resulting from surgical occlusion of vessels, remains a major problem postoperatively and may be an indication for preventive treatment with barbiturates. The author contend that this technique merits further evaluation in cerebro-vascular surgery, especially in high risk cases.

Topics: Adult; Brain Ischemia; Drug Administration Schedule; Female; Humans; Intracranial Aneurysm; Middle Aged; Postoperative Period; Thiopental

Topics: Brain; Humans; Hypothermia, Induced; Intracranial Aneurysm; Ischemic Attack, Transient; Pentobarbital; Retrospective Studies; Thiopental

The authors had observed that on intraoperative discontinuation of sodium nitroprusside being administered to induce hypotension, mean arterial pressure increased to above the pre-hypotension level. Twelve patients who recieved hypotensive anesthesia for surgical correction of cerebral aneurysms were studied to evaluate the role of the renin-angiotensin system in this phenomenon. In the awake state, mean arterial pressure was 100 +/- 2 torr and plasma renin activity 3.0 +/- 0.1 ng/ml/hr. Thirty minutes after the establishment of stable halothane-nitrous oxide anesthesia, mean arterial pressure decreased to 85 +/- 1 torr and plasma renin activity increased to 4.4 +/- 0.1 ng/ml/hr. No appreciable change in either occurred over the next two hours of operation. During sodium nitroprusside-induced hypotension, mean arterial pressure decreased to 49 +/- 2 torr and plasma renin activity increased to 15.2 +/- 0.2 ng/ml/hr. Thirty minutes after discontinuation of sodium nitroprusside administration, mean arterial pressure increased to 112 +/- 2 torr, which was not only higher than the prehypotension level, but also significantly higher than that recorded in the awake state. Plasma renin activity at that time was 10.9 +/- 0.1 ng/ml/hr. As the half-life of plasma renin is 15 min, the data suggest that the persistently increased plasma renin activity is probably responsible for the increase of arterial pressure following sodium nitroprusside-induced hypotension.

Topics: Adolescent; Adult; Anesthesia, General; Blood Pressure; Ferricyanides; Halothane; Humans; Hypertension; Hypotension, Controlled; Injections, Intravenous; Intracranial Aneurysm; Middle Aged; Nitroprusside; Nitrous Oxide; Renin; Thiopental

The anaesthetist giving anaesthesia for the surgical removal of cerebral aneurysms faces a great variety of tasks. Experience gained in the course of 61 such operations has shown that a combination of controlled hypotension, careful monitoring of the function of the autonomic nervous system and a meticulous surgical technique with the aid of a microscope produces satisfactory results.

Topics: Anesthesia, General; Anesthesia, Inhalation; Blood Pressure; Carbon Dioxide; Cerebrovascular Circulation; Halothane; Humans; Hypotension, Controlled; Intracranial Aneurysm; Partial Pressure; Thiopental

A case is reported of a patient with a cerebral aneurysm in whom it was difficult to induce hypotension. The hyperadrenergic state mimicked, in some respects, that seen in patients with neural crest lesions. Possible mechanisms are discussed and the anaesthetic management described.

Topics: Adult; Anesthesia, General; Female; Humans; Hypertension; Hypotension, Controlled; Intracranial Aneurysm; Metanephrine; Nitroprusside; Thiopental; Tubocurarine; Vanilmandelic Acid

Topics: Anesthesia; Basilar Artery; Electric Countershock; Heart Arrest, Induced; Humans; Hypothermia, Induced; Intracranial Aneurysm; Intubation, Intratracheal; Promazine; Thiopental; Tubocurarine

Topics: Anesthesia, General; Blood Pressure Determination; Female; Halothane; Humans; Hypotension, Controlled; Intracranial Aneurysm; Preanesthetic Medication; Pregnancy; Pregnancy Complications, Cardiovascular; Propranolol; Rupture, Spontaneous; Subarachnoid Hemorrhage; Succinylcholine; Thiopental; Trimethaphan

Twenty patients with aneurysms of the internal carotid artery underwent temporary clamping, in turn, of the internal and then the common carotid artery. Cerebral blood flow, internal carotid artery pressure, and the EEG were recorded to assess the probability of cerebral ischaemia after permanent ligation. With this method of monitoring the cerebral circulation, 17 of the 20 patients had a permanent carotid ligation without neurological deficit; in the other three ligation was contraindicated. Although a correlation was observed between the reduction of cerebral blood flow and the fall in internal carotid artery pressure caused by temporary clamping (P<0·01), the scatter of data was too wide to predict cerebral blood flow from the change in carotid artery pressure. Similarly, EEG slowing was usually associated with low cerebral blood flow but exceptions occurred. Ligation was safe when, during temporary clamping, cerebral blood flow exceeded 40 ml/100 g/min, but was deemed unsafe when flow was less than 20 ml/100 g/min. In the range 20-40 ml/100 g/min, consideration of the internal carotid artery pressure permitted more patients to be safely ligated than if the decision had rested on changes in cerebral blood flow alone.

Topics: Adolescent; Adult; Aged; Anesthesia, General; Blood Pressure; Brain; Carotid Artery Diseases; Carotid Artery, Internal; Cerebrovascular Circulation; Electroencephalography; Humans; Hypertension; Intracranial Aneurysm; Ischemia; Middle Aged; Nitrous Oxide; Postoperative Complications; Respiration, Artificial; Subarachnoid Hemorrhage; Thiopental

Topics: Adult; Anesthesia, General; Blood Pressure; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Rupture; Succinylcholine; Thiopental

Topics: Adolescent; Adult; Aneurysm; Angiomatosis; Aorta; Atropine; Blood Circulation; Brain; Catheterization; Child; Coronary Vessels; Electrocardiography; Female; Humans; Hypotension, Controlled; Hypothermia, Induced; Intracranial Aneurysm; Ischemia; Male; Methods; Middle Aged; Perfusion; Preanesthetic Medication; Promazine; Propranolol; Succinylcholine; Thiopental; Thromboembolism; Ventricular Fibrillation