Cerebral blood flow velocity changes under nitrous oxide halothane anesthesia in patients with frontotemporal gliomas: a comparison of the normal and abnormal cerebral hemispheres.

BACKGROUND: Regional differences in vascular response to anesthetic agents in brain areas with and without tumors have not been investigated till now. The existence of such differences may influence the regional distribution of cerebral blood flow under anesthesia. MATERIAL AND METHODS: In 8 patients with frontotemporal gliomas, middle cerebral artery blood flow velocity (VMCA), pulsatality index (PI) and resistance index (RI) were determined in the normal and pathological cerebral hemispheres before and after stable nitrous oxide-halothane anesthesia. RESULTS: During halothane anesthesia, there was an increase in VMCA both in the normal cerebral hemisphere (69 +/- 11 to 100 +/- 38 cm/s; P = 0.05) and the hemisphere with tumor (65 +/- 17 to 83 +/- 28 cm/s; P = 0.04). A significant decrease in the pulsatality index and the resistance index was also observed in both the hemispheres (P < 0.05). The percentage changes of VMCA, PI and RI in both the hemispheres after anesthesia were not significantly different. CONCLUSIONS: In patients with cerebral tumors, nitrous oxide-halothane anesthesia causes comparable changes of cerebral blood flow velocities in the hemisphere with tumor and the normal hemisphere.

Evaluation of nimodipine in the treatment of severe diffuse head injury: a double-blind placebo-controlled trial.

AIMS: The aim of this study was to establish whether nimodipine given orally soon after severe diffuse head injury for a period of three weeks improved outcome. MATERIAL AND METHODS: The present report analyzes the results of a prospective randomized double-blind placebo-controlled trial of nimodipine in 97 severe head injury patients (GCS Score < or =8) treated at the Department of Neurosurgery, NIMHANS, between January 1995 and June 1996. The patients were randomly assigned to two groups which were matched for age, sex, mode of injury, time interval from injury to admission, neurological status and CT scan findings. One group was given nimodipine 30 mg Q6H and the other group was given a placebo. The outcome of these patients at 6 months was evaluated using the Glasgow Outcome Score by and a psychologist. RESULTS: Results showed no significant difference in the functional and psychological outcome between the two groups, even in patients with subarachnoid hemorrhage. No adverse drug events were recorded. CONCLUSION: Oral nimodipine given for three weeks does not improve outcome in patients with severe diffuse head injury.

Outcome prediction model for severe diffuse brain injuries: development and evaluation.

BACKGROUND: Intensive care resources for the management of severe diffuse brain injury patients (SDBI) are limited. Their optimal use is possible only if we can predict at admission which patients are unlikely to improve. AIMS: To develop a simple and effective model to predict poor outcome in patients with SDBI in order to help guide initial therapy. MATERIAL AND METHODS: The prognostic factors and outcomes of 289 patients with severe diffuse brain injury (GCS 3-8) were analyzed retrospectively. The prognostic factors analyzed were age, mode of injury, GCS at admission, pupillary reaction, horizontal oculocephalic reflex, and CT scan findings. Outcome at 1 month was classified as unfavorable--death or persistent vegetative state, or favorable--improvement with or without some disability. A stepwise linear logistic regression analysis was used to identify the most important predictors of poor outcome. A prediction model (NIMHANS model-NM) was developed using these factors. NM and several currently available outcome prediction models were prospectively applied in a separate group of 26 patients with severe diffuse brain injury managed with a different protocol. RESULTS: The most important predictors of poor outcome were found to be the horizontal oculocephalic reflex, motor score of GCS, and midline shift on CT scan. NM was found to be more sensitive (75%) and specific (67%) than most other models in predicting unfavorable outcome. NM had high false pessimistic results (33%). CONCLUSION: Prediction models cannot be used to guide initial therapy.