Efficacy of prophylactic nimodipine for delayed ischemic deficit after subarachnoid hemorrhage: a metaanalysis

View More View Less
  • 1 Brain Tumor Research Center, Department of Neurological Surgery, University of California at San Francisco, San Francisco, California; and Cerebrovascular Surgery, Neurosurgical Service, Massachusetts General Hospital, and Department of Surgery, Harvard Medical School, Boston, Massachusetts
Restricted access

Purchase Now

USD  $45.00

JNS + Pediatrics - 1 year subscription bundle (Individuals Only)

USD  $505.00

JNS + Pediatrics + Spine - 1 year subscription bundle (Individuals Only)

USD  $600.00
Print or Print + Online

✓ The authors report findings from a metaanalysis of all published randomized trials of prophylactic nimodipine used in patients who have experienced subarachnoid hemorrhage (SAH). Seven trials were included with a total of 1202 patients suitable for evaluation. Eight outcome measures were examined, including good versus other outcome, good or fair outcome versus other outcome, overall mortality, deficit and/or death attributed to vasospasm, infarction rate as judged by computerized tomography (CT), and deficit and/or death from rebleeding.

Nimodipine improved outcome according to all measures examined. The odds of good and of good plus fair outcomes were improved by ratios of 1.86:1 and 1.67:1, respectively, for nimodipine versus control (p < 0.005 for both measures). The odds of deficit and/or mortality attributed to vasospasm and CT-assessed infarction rate were reduced by ratios of 0.46:1 to 0.58:1 in the nimodipine group (p < 0.008 for all measures). Overall mortality was slightly reduced in the nimodipine group, but the trend was not statistically significant. The rebleeding rate was not increased by nimodipine. A metaregression yielded findings indicating that the treatment effect of nimodipine in individual trials was positively correlated with the severity of SAH in enrolled patients.

Although the majority of individual trials examined did not have statistically significant results at the p < 0.01 level according to most outcome measures, the metaanalyses confirmed the significant efficacy of prophylactic nimodipine in improving outcome after SAH under the conditions used in these trials.

JNS + Pediatrics - 1 year subscription bundle (Individuals Only)

USD  $505.00

JNS + Pediatrics + Spine - 1 year subscription bundle (Individuals Only)

USD  $600.00

Contributor Notes

Address reprint requests to: Fred G. Barker, M.D., Neurosurgical Service, White 5, Massachusetts General Hospital, 32 Fruit Street, Boston, Massachusetts 02114.
  • 1.

    Adams HP Jr: Calcium antagonists in the management of patients with aneurysmal subarachnoid hemorrhage: a review. Angiology 41:10101016, 1990 Adams HP Jr: Calcium antagonists in the management of patients with aneurysmal subarachnoid hemorrhage: a review. Angiology 41:1010–1016, 1990

    • Search Google Scholar
    • Export Citation
  • 2.

    Agresti A: Categorical Data Analysis. New York: John Wiley & Sons, 1990 Agresti A: Categorical Data Analysis. New York: John Wiley & Sons, 1990

    • Search Google Scholar
    • Export Citation
  • 3.

    Allen GS, , Ahn HS, & Preziosi TJ, et al: Cerebral arterial spasm—a controlled trial of nimodipine in patients with subarachnoid hemorrhage. N Engl J Med 308:619624, 1983 Allen GS, Ahn HS, Preziosi TJ, et al: Cerebral arterial spasm—a controlled trial of nimodipine in patients with subarachnoid hemorrhage. N Engl J Med 308:619–624, 1983

    • Search Google Scholar
    • Export Citation
  • 4.

    Anderson JL, , Platia EV, & Hallstrom A, et al: Interaction of baseline characteristics with the hazard of encainide, flecainide, and moricizine therapy in patients with myocardial infarction. A possible explanation for increased mortality in the Cardiac Arrhythmia Suppression Trial (CAST). Circulation 90:28432852, 1994 Anderson JL, Platia EV, Hallstrom A, et al: Interaction of baseline characteristics with the hazard of encainide, flecainide, and moricizine therapy in patients with myocardial infarction. A possible explanation for increased mortality in the Cardiac Arrhythmia Suppression Trial (CAST). Circulation 90:2843–2852, 1994

    • Search Google Scholar
    • Export Citation
  • 5.

    Barker FG II: Efficacy of prophylactic antibiotics for craniotomy: a metaanalysis. Neurosurgery 35:484492, 1994 Barker FG II: Efficacy of prophylactic antibiotics for craniotomy: a metaanalysis. Neurosurgery 35:484–492, 1994

    • Search Google Scholar
    • Export Citation
  • 6.

    Barker FG II, & Heros RC: Clinical aspects of vasospasm. Neurosurg Clin North Am 1:277288, 1990 Barker FG II, Heros RC: Clinical aspects of vasospasm. Neurosurg Clin North Am 1:277–288, 1990

    • Search Google Scholar
    • Export Citation
  • 7.

    Begg CB, & Berlin JA: Publication bias: a problem in interpreting medical data. J R Stat Soc (A) 151:419463, 1988 Begg CB, Berlin JA: Publication bias: a problem in interpreting medical data. J R Stat Soc (A) 151:419–463, 1988

    • Search Google Scholar
    • Export Citation
  • 8.

    Berlin JA, & Antman EM: Advantages and limitations of metaanalytic regressions of clinical trials data. Online J Curr Clin Trials 4:Doc No 134, 1994 Berlin JA, Antman EM: Advantages and limitations of metaanalytic regressions of clinical trials data. Online J Curr Clin Trials 4:Doc No 134, 1994

    • Search Google Scholar
    • Export Citation
  • 9.

    Berlin JA, , Laird NM, & Sacks HS, et al: A comparison of statistical methods for combining event rates from clinical trials. Stat Med 8:141151, 1989 Berlin JA, Laird NM, Sacks HS, et al: A comparison of statistical methods for combining event rates from clinical trials. Stat Med 8:141–151, 1989

    • Search Google Scholar
    • Export Citation
  • 10.

    Brand R, & Kragt H: Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials. Stat Med 11:20772082, 1992 Brand R, Kragt H: Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials. Stat Med 11:2077–2082, 1992

    • Search Google Scholar
    • Export Citation
  • 11.

    Brandt L, , Säveland H, & Romner B, et al: Does nimodipine eliminate arterial hypertension as a prognostic risk factor in subarachnoid haemorrhage? Br J Neurosurg 5:485489, 1991 Brandt L, Säveland H, Romner B, et al: Does nimodipine eliminate arterial hypertension as a prognostic risk factor in subarachnoid haemorrhage? Br J Neurosurg 5:485–489, 1991

    • Search Google Scholar
    • Export Citation
  • 12.

    Cardiac Arrhythmia Pilot Study (CAPS) Investigators: Effects of encainide, flecainide, imipramine and moricizine on ventricular arrhythmias during the year after acute myocardial infarction: the CAPS. Am J Cardiol 61:501509, 1988 Cardiac Arrhythmia Pilot Study (CAPS) Investigators: Effects of encainide, flecainide, imipramine and moricizine on ventricular arrhythmias during the year after acute myocardial infarction: the CAPS. Am J Cardiol 61:501–509, 1988

    • Search Google Scholar
    • Export Citation
  • 13.

    Cardiac Arrhythmia Suppression Trial Investigators: Preliminary report: effect of encainide and flecainide on mortality in a randomized trial of arrhythmia suppression after myocardial infarction. N Engl J Med 321:406412, 1989 Cardiac Arrhythmia Suppression Trial Investigators: Preliminary report: effect of encainide and flecainide on mortality in a randomized trial of arrhythmia suppression after myocardial infarction. N Engl J Med 321:406–412, 1989

    • Search Google Scholar
    • Export Citation
  • 14.

    Chalmers TC: Problems induced by meta-analyses. Stat Med 10:971980, 1991 Chalmers TC: Problems induced by meta-analyses. Stat Med 10:971–980, 1991

    • Search Google Scholar
    • Export Citation
  • 15.

    Chyatte D, , Fode NC, & Sundt TM Jr: Early versus late intracranial aneurysm surgery in subarachnoid hemorrhage. J Neurosurg 69:326331, 1988 Chyatte D, Fode NC, Sundt TM Jr: Early versus late intracranial aneurysm surgery in subarachnoid hemorrhage. J Neurosurg 69:326–331, 1988

    • Search Google Scholar
    • Export Citation
  • 16.

    Cochran WG: The combination of estimates from different experiments. Biometrics 10:101129, 1954 Cochran WG: The combination of estimates from different experiments. Biometrics 10:101–129, 1954

    • Search Google Scholar
    • Export Citation
  • 17.

    Cook DJ, , Sackett DL, & Spitzer WO: Methodologic guidelines for systematic reviews of randomized control trials in health care from the Potsdam Consultation on Meta-Analysis. J Clin Epidemiol 48:167171, 1995 Cook DJ, Sackett DL, Spitzer WO: Methodologic guidelines for systematic reviews of randomized control trials in health care from the Potsdam Consultation on Meta-Analysis. J Clin Epidemiol 48:167–171, 1995

    • Search Google Scholar
    • Export Citation
  • 18.

    Cook RJ, & Sackett DL: The number needed to treat: a clinically useful measure of treatment effect. Br Med J 310:452454, 1995 Cook RJ, Sackett DL: The number needed to treat: a clinically useful measure of treatment effect. Br Med J 310:452–454, 1995

    • Search Google Scholar
    • Export Citation
  • 19.

    DerSimonian R, & Laird N: Meta-analysis in clinical trials. Control Clin Trials 7:177188, 1986 DerSimonian R, Laird N: Meta-analysis in clinical trials. Control Clin Trials 7:177–188, 1986

    • Search Google Scholar
    • Export Citation
  • 20.

    Desbordes JM, , Ades PE, & Guggiari M: Nimodipine intraveineuse dans le traitement curatif du vasospasme cérébral secondaire aux hémorragies méningées par rupture anévrysmale: étude comparative multicentrique. Agressologie 30:438440, 1989 Desbordes JM, Ades PE, Guggiari M: Nimodipine intraveineuse dans le traitement curatif du vasospasme cérébral secondaire aux hémorragies méningées par rupture anévrysmale: étude comparative multicentrique. Agressologie 30:438–440, 1989

    • Search Google Scholar
    • Export Citation
  • 21.

    Di Mascio R, , Marchioli R, & Tognoni G: From pharmacological promises to controlled clinical trials to meta-analysis and back: the case of nimodipine in cerebrovascular disorders. Clin Trials Meta-Analysis 29:5779, 1994 Di Mascio R, Marchioli R, Tognoni G: From pharmacological promises to controlled clinical trials to meta-analysis and back: the case of nimodipine in cerebrovascular disorders. Clin Trials Meta-Analysis 29:57–79, 1994

    • Search Google Scholar
    • Export Citation
  • 22.

    Dickersin K, & Min YI: Publication bias: the problem that won't go away. Ann N Y Acad Sci 703:135148, 1993 Dickersin K, Min YI: Publication bias: the problem that won't go away. Ann N Y Acad Sci 703:135–148, 1993

    • Search Google Scholar
    • Export Citation
  • 23.

    Dickersin K, , Min YI, & Meinert CL: Factors influencing publication of research results. Follow-up of applications submitted to two institutional review boards. JAMA 267:374378, 1992 Dickersin K, Min YI, Meinert CL: Factors influencing publication of research results. Follow-up of applications submitted to two institutional review boards. JAMA 267:374–378, 1992

    • Search Google Scholar
    • Export Citation
  • 24.

    Dorsch NWC: A review of cerebral vasospasm in aneurysmal subarachnoid haemorrhage. Part II: Management. J Clin Neurosci 1:7892, 1994 Dorsch NWC: A review of cerebral vasospasm in aneurysmal subarachnoid haemorrhage. Part II: Management. J Clin Neurosci 1:78–92, 1994

    • Search Google Scholar
    • Export Citation
  • 25.

    Dorsch NWC, & King MT: A review of cerebral vasospasm in aneurysmal subarachnoid haemorrhage. Part I: Incidence and effects. J Clin Neurosci 1:1926, 1994 Dorsch NWC, King MT: A review of cerebral vasospasm in aneurysmal subarachnoid haemorrhage. Part I: Incidence and effects. J Clin Neurosci 1:19–26, 1994

    • Search Google Scholar
    • Export Citation
  • 26.

    Easterbrook PJ, , Berlin JA, & Gopalan R, et al: Publication bias in clinical research. Lancet 337:867872, 1991 Easterbrook PJ, Berlin JA, Gopalan R, et al: Publication bias in clinical research. Lancet 337:867–872, 1991

    • Search Google Scholar
    • Export Citation
  • 27.

    Echt DS, , Liebson PR, & Mitchell LB, et al: Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial. N Engl J Med 324:781788, 1991 Echt DS, Liebson PR, Mitchell LB, et al: Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial. N Engl J Med 324:781–788, 1991

    • Search Google Scholar
    • Export Citation
  • 28.

    Eskridge JM, , Newell DW, & Winn HR: Endovascular treatment of vasospasm. Neurosurg Clin North Am 5:437447, 1994 Eskridge JM, Newell DW, Winn HR: Endovascular treatment of vasospasm. Neurosurg Clin North Am 5:437–447, 1994

    • Search Google Scholar
    • Export Citation
  • 29.

    Felson DT: Bias in meta-analytic research. J Clin Epidemiol 45:885892, 1992 Felson DT: Bias in meta-analytic research. J Clin Epidemiol 45:885–892, 1992

    • Search Google Scholar
    • Export Citation
  • 30.

    Flamm ES, , Adams HP Jr, & Beck DW, et al: Dose-escalation study of intravenous nicardipine in patients with aneurysmal subarachnoid hemorrhage. J Neurosurg 68:393400, 1988 Flamm ES, Adams HP Jr, Beck DW, et al: Dose-escalation study of intravenous nicardipine in patients with aneurysmal subarachnoid hemorrhage. J Neurosurg 68:393–400, 1988

    • Search Google Scholar
    • Export Citation
  • 31.

    Fleiss JL: Statistical Methods for Rates and Proportions, ed 2. New York: Wiley, 1981 Fleiss JL: Statistical Methods for Rates and Proportions, ed 2. New York: Wiley, 1981

    • Search Google Scholar
    • Export Citation
  • 32.

    Frerebeau P, , Janny P, & Taquoi G, et al: Traitement curatif du vasospasme des hémorragies méningées d'origine anévrysmale par la nimodipine intraveineuse. Etude coopérative multicentrique. Neurochirurgie 34:383388, 1988 Frerebeau P, Janny P, Taquoi G, et al: Traitement curatif du vasospasme des hémorragies méningées d'origine anévrysmale par la nimodipine intraveineuse. Etude coopérative multicentrique. Neurochirurgie 34:383–388, 1988

    • Search Google Scholar
    • Export Citation
  • 33.

    Fujita S, , Kawaguchi T, & Shose Y, et al: Flunarizine treatment in poor-grade aneurysm patients. Acta Neurochir 103:1117, 1990 Fujita S, Kawaguchi T, Shose Y, et al: Flunarizine treatment in poor-grade aneurysm patients. Acta Neurochir 103:11–17, 1990

    • Search Google Scholar
    • Export Citation
  • 34.

    Gilsbach JM: Nimodipine in the prevention of ischaemic deficits after aneurysmal subarachnoid haemorrhage. An analysis of recent clinical studies. Acta Neurochir Suppl 45:4150, 1988 Gilsbach JM: Nimodipine in the prevention of ischaemic deficits after aneurysmal subarachnoid haemorrhage. An analysis of recent clinical studies. Acta Neurochir Suppl 45:41–50, 1988

    • Search Google Scholar
    • Export Citation
  • 35.

    Gilsbach JM, , Reulen HJ, & Ljunggren B, et al: Early aneurysm surgery and preventive therapy with intravenously administered nimodipine: a multicenter, double-blind, dose-comparison study. Neurosurgery 26:458464, 1990 Gilsbach JM, Reulen HJ, Ljunggren B, et al: Early aneurysm surgery and preventive therapy with intravenously administered nimodipine: a multicenter, double-blind, dose-comparison study. Neurosurgery 26:458–464, 1990

    • Search Google Scholar
    • Export Citation
  • 36.

    Haley EC Jr, , Kassell NF, & Alves WM, et al: Phase II trial of tirilazad in aneurysmal subarachnoid hemorrhage. A report of the Cooperative Aneurysm Study. J Neurosurg 82:786790, 1995 Haley EC Jr, Kassell NF, Alves WM, et al: Phase II trial of tirilazad in aneurysmal subarachnoid hemorrhage. A report of the Cooperative Aneurysm Study. J Neurosurg 82:786–790, 1995

    • Search Google Scholar
    • Export Citation
  • 37.

    Haley EC Jr, , Kassell NF, & Torner JC, et al: A randomized controlled trial of high-dose intravenous nicardipine in aneurysmal subarachnoid hemorrhage. A report of the Cooperative Aneurysm Study. J Neurosurg 78:537547, 1993 Haley EC Jr, Kassell NF, Torner JC, et al: A randomized controlled trial of high-dose intravenous nicardipine in aneurysmal subarachnoid hemorrhage. A report of the Cooperative Aneurysm Study. J Neurosurg 78:537–547, 1993

    • Search Google Scholar
    • Export Citation
  • 38.

    Haley EC Jr, , Kassell NF, & Torner JC, et al: A randomized trial of nicardipine in subarachnoid hemorrhage: angiographic and transcranial Doppler ultrasound results. A report of the Cooperative Aneurysm Study. J Neurosurg 78:548553, 1993 Haley EC Jr, Kassell NF, Torner JC, et al: A randomized trial of nicardipine in subarachnoid hemorrhage: angiographic and transcranial Doppler ultrasound results. A report of the Cooperative Aneurysm Study. J Neurosurg 78:548–553, 1993

    • Search Google Scholar
    • Export Citation
  • 39.

    Han DH, , Lee SH, & Lee SH: Effect of nimodipine treatment on outcome in surgical cases of aneurysmal SAH. J Neurosurg 78:346A, 1993 Han DH, Lee SH, Lee SH: Effect of nimodipine treatment on outcome in surgical cases of aneurysmal SAH. J Neurosurg 78:346A, 1993

    • Search Google Scholar
    • Export Citation
  • 40.

    Higashida RT, , Halbach VV, & Cahan LD, et al: Transluminal angioplasty for treatment of intracranial arterial vasospasm. J Neurosurg 71:648653, 1989 Higashida RT, Halbach VV, Cahan LD, et al: Transluminal angioplasty for treatment of intracranial arterial vasospasm. J Neurosurg 71:648–653, 1989

    • Search Google Scholar
    • Export Citation
  • 41.

    Hongo K, & Kobayashi S: Calcium antagonists for the treatment of vasospasm following subarachnoid haemorrhage. Neurol Res 15:218224, 1993 Hongo K, Kobayashi S: Calcium antagonists for the treatment of vasospasm following subarachnoid haemorrhage. Neurol Res 15:218–224, 1993

    • Search Google Scholar
    • Export Citation
  • 42.

    Horner SM: Efficacy of intravenous magnesium in acute myocardial infarction in reducing arrhythmias and mortality. Metaanalysis of magnesium in acute myocardial infarction. Circulation 86:774779, 1992 Horner SM: Efficacy of intravenous magnesium in acute myocardial infarction in reducing arrhythmias and mortality. Metaanalysis of magnesium in acute myocardial infarction. Circulation 86:774–779, 1992

    • Search Google Scholar
    • Export Citation
  • 43.

    Hunt WE, & Hess RM: Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 28:1420, 1968 Hunt WE, Hess RM: Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 28:14–20, 1968

    • Search Google Scholar
    • Export Citation
  • 44.

    ISIS-4 (Fourth International Study of Infarct Survival) Collaborative Group: ISIS-4: a randomised factorial trial assessing early oral captopril, oral mononitrate, and intravenous magnesium sulphate in 58,050 patients with suspected acute myocardial infarction. Lancet 345:669685, 1995 ISIS-4 (Fourth International Study of Infarct Survival) Collaborative Group: ISIS-4: a randomised factorial trial assessing early oral captopril, oral mononitrate, and intravenous magnesium sulphate in 58,050 patients with suspected acute myocardial infarction. Lancet 345:669–685, 1995

    • Search Google Scholar
    • Export Citation
  • 45.

    Jan M, , Buchheit F, & Tremoulet M: Therapeutic trial of intravenous nimodipine in patients with established cerebral vasospasm after rupture of intracranial aneurysms. Neurosurgery 23:154157, 1988 Jan M, Buchheit F, Tremoulet M: Therapeutic trial of intravenous nimodipine in patients with established cerebral vasospasm after rupture of intracranial aneurysms. Neurosurgery 23:154–157, 1988

    • Search Google Scholar
    • Export Citation
  • 46.

    Jennett B, & Bond M: Assessment of outcome after severe brain damage. A practical scale. Lancet 1:480484, 1975 Jennett B, Bond M: Assessment of outcome after severe brain damage. A practical scale. Lancet 1:480–484, 1975

    • Search Google Scholar
    • Export Citation
  • 47.

    Jones DR: Meta-analysis: weighing the evidence. Stat Med 14:137149, 1995 Jones DR: Meta-analysis: weighing the evidence. Stat Med 14:137–149, 1995

    • Search Google Scholar
    • Export Citation
  • 48.

    Kassell NF, , Torner JC, & Haley EC Jr, et al: The International Cooperative Study on the Timing of Aneurysm Surgery. Part 1: Overall management results. J Neurosurg 73:1836, 1990 Kassell NF, Torner JC, Haley EC Jr, et al: The International Cooperative Study on the Timing of Aneurysm Surgery. Part 1: Overall management results. J Neurosurg 73:18–36, 1990

    • Search Google Scholar
    • Export Citation
  • 49.

    Langley MS, & Sorkin EM: Nimodipine. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in cerebrovascular disease. Drugs 37:669699, 1989 Langley MS, Sorkin EM: Nimodipine. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in cerebrovascular disease. Drugs 37:669–699, 1989

    • Search Google Scholar
    • Export Citation
  • 50.

    Mayberg MR, , Batjer HH, & Dacey R, et al: Guidelines for the management of aneurysmal subarachnoid hemorrhage. A statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association. Stroke 25:23152328, 1994 Mayberg MR, Batjer HH, Dacey R, et al: Guidelines for the management of aneurysmal subarachnoid hemorrhage. A statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association. Stroke 25:2315–2328, 1994

    • Search Google Scholar
    • Export Citation
  • 51.

    Mee E, , Dorrance D, & Lowe D, et al: Controlled study of nimodipine in aneurysm patients treated early after subarachnoid hemorrhage. Neurosurgery 22:484491, 1988 Mee E, Dorrance D, Lowe D, et al: Controlled study of nimodipine in aneurysm patients treated early after subarachnoid hemorrhage. Neurosurgery 22:484–491, 1988

    • Search Google Scholar
    • Export Citation
  • 52.

    Mehta CR, , Patel NR, & Gray R: On computing an exact confidence interval for the common odds ratio in several 2 × 2 contingency tables. J Am Stat Assoc 80:969973, 1985 Mehta CR, Patel NR, Gray R: On computing an exact confidence interval for the common odds ratio in several 2 × 2 contingency tables. J Am Stat Assoc 80:969–973, 1985

    • Search Google Scholar
    • Export Citation
  • 53.

    Mercier P, , Alhayek G, & Rizk T, et al: Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study. Neurosurgery 34:3037, 1994 Mercier P, Alhayek G, Rizk T, et al: Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study. Neurosurgery 34:30–37, 1994

    • Search Google Scholar
    • Export Citation
  • 54.

    Mercier P, , Alhayek G, & Rizk T, et al: Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study. Neurosurgery 35:542, 1994 (Letter) Mercier P, Alhayek G, Rizk T, et al: Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study. Neurosurgery 35:542, 1994 (Letter)

    • Search Google Scholar
    • Export Citation
  • 55.

    Mercier P, , Alhayek G, & Rizk T, et al: Les anticalciques sont-ils réellement utiles en chirurgie anévrysmale cérébrale? Neurochirurgie 39:149156, 1993 Mercier P, Alhayek G, Rizk T, et al: Les anticalciques sont-ils réellement utiles en chirurgie anévrysmale cérébrale? Neurochirurgie 39:149–156, 1993

    • Search Google Scholar
    • Export Citation
  • 56.

    Messeter K, , Brandt L, & Ljunggren B, et al: Prediction and prevention of delayed ischemic dysfunction after aneurysmal subarachnoid hemorrhage and early operation. Neurosurgery 20:548553, 1987 Messeter K, Brandt L, Ljunggren B, et al: Prediction and prevention of delayed ischemic dysfunction after aneurysmal subarachnoid hemorrhage and early operation. Neurosurgery 20:548–553, 1987

    • Search Google Scholar
    • Export Citation
  • 57.

    Miyaoka M, , Sato K, & Ishii S: A clinical study of the relationship of timing to outcome of surgery for ruptured cerebral aneurysms. A retrospective analysis of 1622 cases. J Neurosurg 79:373378, 1993 Miyaoka M, Sato K, Ishii S: A clinical study of the relationship of timing to outcome of surgery for ruptured cerebral aneurysms. A retrospective analysis of 1622 cases. J Neurosurg 79:373–378, 1993

    • Search Google Scholar
    • Export Citation
  • 58.

    Neil-Dwyer G, , Mee E, & Dorrance D, et al: Early intervention with nimodipine in subarachnoid haemorrhage. Eur Heart J 8 (Suppl K):4147, 1987 Neil-Dwyer G, Mee E, Dorrance D, et al: Early intervention with nimodipine in subarachnoid haemorrhage. Eur Heart J 8 (Suppl K):41–47, 1987

    • Search Google Scholar
    • Export Citation
  • 59.

    Newell DW, , Eskridge JM, & Mayberg MR, et al: Angioplasty for the treatment of symptomatic vasospasm following subarachnoid hemorrhage. J Neurosurg 71:654660, 1989 Newell DW, Eskridge JM, Mayberg MR, et al: Angioplasty for the treatment of symptomatic vasospasm following subarachnoid hemorrhage. J Neurosurg 71:654–660, 1989

    • Search Google Scholar
    • Export Citation
  • 60.

    Öhman J, & Heiskanen O: Effect of nimodipine on the outcome of patients after aneurysmal subarachnoid hemorrhage and surgery. J Neurosurg 69:683686, 1988 Öhman J, Heiskanen O: Effect of nimodipine on the outcome of patients after aneurysmal subarachnoid hemorrhage and surgery. J Neurosurg 69:683–686, 1988

    • Search Google Scholar
    • Export Citation
  • 61.

    Öhman J, , Servo A, & Heiskanen O: Long-term effects of nimodipine on cerebral infarcts and outcome after aneurysmal subarachnoid hemorrhage and surgery. J Neurosurg 74:813, 1991 Öhman J, Servo A, Heiskanen O: Long-term effects of nimodipine on cerebral infarcts and outcome after aneurysmal subarachnoid hemorrhage and surgery. J Neurosurg 74:8–13, 1991

    • Search Google Scholar
    • Export Citation
  • 62.

    Öhman J, , Servo A, & Heiskanen O: Risks factors for cerebral infarction in good-grade patients after aneurysmal subarachnoid hemorrhage and surgery: a prospective study. J Neurosurg 74:1420, 1991 Öhman J, Servo A, Heiskanen O: Risks factors for cerebral infarction in good-grade patients after aneurysmal subarachnoid hemorrhage and surgery: a prospective study. J Neurosurg 74:14–20, 1991

    • Search Google Scholar
    • Export Citation
  • 63.

    Olkin I: Meta-analysis: reconciling the results of independent studies. Stat Med 14:457472, 1995 Olkin I: Meta-analysis: reconciling the results of independent studies. Stat Med 14:457–472, 1995

    • Search Google Scholar
    • Export Citation
  • 64.

    Origitano TC, , Wascher TM, & Reichman OH, et al: Sustained increased cerebral blood flow with prophylactic hypertensive hypervolemic hemodilution (“Triple-H”) therapy after subarachnoid hemorrhage. Neurosurgery 27:729740, 1990 Origitano TC, Wascher TM, Reichman OH, et al: Sustained increased cerebral blood flow with prophylactic hypertensive hypervolemic hemodilution (“Triple-H”) therapy after subarachnoid hemorrhage. Neurosurgery 27:729–740, 1990

    • Search Google Scholar
    • Export Citation
  • 65.

    Pellettieri L, , Bolander H, & Carlsson H, et al: Nimodipine treatment of selected good-risk patients with subarachnoid hemorrhage: no significant difference between present and historical results. Surg Neurol 30:180186, 1988 Pellettieri L, Bolander H, Carlsson H, et al: Nimodipine treatment of selected good-risk patients with subarachnoid hemorrhage: no significant difference between present and historical results. Surg Neurol 30:180–186, 1988

    • Search Google Scholar
    • Export Citation
  • 66.

    Peroutka SJ, , Banghart SB, & Allen GS: Relative potency and selectivity of calcium antagonists used in the treatment of migraine. Headache 24:5558, 1984 Peroutka SJ, Banghart SB, Allen GS: Relative potency and selectivity of calcium antagonists used in the treatment of migraine. Headache 24:55–58, 1984

    • Search Google Scholar
    • Export Citation
  • 67.

    Petruk KC, , West M, & Mohr G, et al: Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial. J Neurosurg 68:505517, 1988 Petruk KC, West M, Mohr G, et al: Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial. J Neurosurg 68:505–517, 1988

    • Search Google Scholar
    • Export Citation
  • 68.

    Philippon J, , Grob R, & Dagreou F, et al: Prevention of vasospasm in subarachnoid haemorrhage. A controlled study with nimodipine. Acta Neurochir 82:110114, 1986 Philippon J, Grob R, Dagreou F, et al: Prevention of vasospasm in subarachnoid haemorrhage. A controlled study with nimodipine. Acta Neurochir 82:110–114, 1986

    • Search Google Scholar
    • Export Citation
  • 69.

    Pickard JD, , Murray GD, & Illingworth R, et al: Effect of oral nimodipine on cerebral infarction and outcome after subarachnoid haemorrhage: British aneurysm nimodipine trial. Br Med J 298:636642, 1989 Pickard JD, Murray GD, Illingworth R, et al: Effect of oral nimodipine on cerebral infarction and outcome after subarachnoid haemorrhage: British aneurysm nimodipine trial. Br Med J 298:636–642, 1989

    • Search Google Scholar
    • Export Citation
  • 70.

    Popovic EA, , Danks RA, & Siu KH: Experience with nimodipine in aneurysmal subarachnoid haemorrhage. Med J Aust 158:9194, 1993 Popovic EA, Danks RA, Siu KH: Experience with nimodipine in aneurysmal subarachnoid haemorrhage. Med J Aust 158:91–94, 1993

    • Search Google Scholar
    • Export Citation
  • 71.

    Rosenthal R: The “file drawer problem” and tolerance for null results. Psychol Bull 86:638641, 1979 Rosenthal R: The “file drawer problem” and tolerance for null results. Psychol Bull 86:638–641, 1979

    • Search Google Scholar
    • Export Citation
  • 72.

    Rousseaux P, , Gomis P, & Bazin A, et al: Comparaison de deux séries consécutives d'hemorragies méningées anévrysmales avec et sans nimodipine et étude de la courbe thermique. Neurochirurgie 39:157165, 1993 Rousseaux P, Gomis P, Bazin A, et al: Comparaison de deux séries consécutives d'hemorragies méningées anévrysmales avec et sans nimodipine et étude de la courbe thermique. Neurochirurgie 39:157–165, 1993

    • Search Google Scholar
    • Export Citation
  • 73.

    Sekhar LN, , Wechsler LR, & Yonas H, et al: Value of transcranial Doppler examination in the diagnosis of cerebral vasospasm after subarachnoid hemorrhage. Neurosurgery 22:813821, 1988 Sekhar LN, Wechsler LR, Yonas H, et al: Value of transcranial Doppler examination in the diagnosis of cerebral vasospasm after subarachnoid hemorrhage. Neurosurgery 22:813–821, 1988

    • Search Google Scholar
    • Export Citation
  • 74.

    Senn S: Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials. Stat Med 13:293296, 1994 (Letter) Senn S: Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials. Stat Med 13:293–296, 1994 (Letter)

    • Search Google Scholar
    • Export Citation
  • 75.

    Shibuya M, , Suzuki Y, & Sugita K, et al: Dose escalation trial of a novel calcium antagonist, AT877, in patients with aneurysmal subarachnoid haemorrhage. Acta Neurochir 107:1115, 1990 Shibuya M, Suzuki Y, Sugita K, et al: Dose escalation trial of a novel calcium antagonist, AT877, in patients with aneurysmal subarachnoid haemorrhage. Acta Neurochir 107:11–15, 1990

    • Search Google Scholar
    • Export Citation
  • 76.

    Shibuya M, , Suzuki Y, & Sugita K, et al: Effect of AT877 on cerebral vasospasm after aneurysmal subarachnoid hemorrhage. Results of a prospective placebo-controlled double-blind trial. J Neurosurg 76:571577, 1992 Shibuya M, Suzuki Y, Sugita K, et al: Effect of AT877 on cerebral vasospasm after aneurysmal subarachnoid hemorrhage. Results of a prospective placebo-controlled double-blind trial. J Neurosurg 76:571–577, 1992

    • Search Google Scholar
    • Export Citation
  • 77.

    Sprent P: Applied Nonparametric Statistical Methods, ed 2. London: Chapman & Hall, 1993 Sprent P: Applied Nonparametric Statistical Methods, ed 2. London: Chapman & Hall, 1993

    • Search Google Scholar
    • Export Citation
  • 78.

    Sundt TM Jr, , Kobayashi S, & Fode NC, et al: Results and complications of surgical management of 809 intracranial aneurysms in 722 cases. Related and unrelated to grade of patient, type of aneurysm, and timing of surgery. J Neurosurg 56:753765, 1982 Sundt TM Jr, Kobayashi S, Fode NC, et al: Results and complications of surgical management of 809 intracranial aneurysms in 722 cases. Related and unrelated to grade of patient, type of aneurysm, and timing of surgery. J Neurosurg 56:753–765, 1982

    • Search Google Scholar
    • Export Citation
  • 79.

    Takagi T, , Kuwahara M, & Nagai H, et al: [Effect of calcium antagonist (diltiazem) on symptomatic cerebral vasospasm.] Neurol Med Chir 26:863869, 1986 (Jpn) Takagi T, Kuwahara M, Nagai H, et al: [Effect of calcium antagonist (diltiazem) on symptomatic cerebral vasospasm.] Neurol Med Chir 26:863–869, 1986 (Jpn)

    • Search Google Scholar
    • Export Citation
  • 80.

    Teo KK, & Yusuf S: Role of magnesium in reducing mortality in acute myocardial infarction. A review of the evidence. Drugs 46:347359, 1993 Teo KK, Yusuf S: Role of magnesium in reducing mortality in acute myocardial infarction. A review of the evidence. Drugs 46:347–359, 1993

    • Search Google Scholar
    • Export Citation
  • 81.

    Teo KK, , Yusuf S, & Collins R, et al: Effects of intravenous magnesium in suspected acute myocardial infarction: overview of randomised trials. Br Med J 303:14991503, 1991 Teo KK, Yusuf S, Collins R, et al: Effects of intravenous magnesium in suspected acute myocardial infarction: overview of randomised trials. Br Med J 303:1499–1503, 1991

    • Search Google Scholar
    • Export Citation
  • 82.

    Tettenborn D, & Dycka J: Prevention and treatment of delayed ischemic dysfunction in patients with aneurysmal subarachnoid hemorrhage. Stroke 21 (Suppl IV):8589, 1990 Tettenborn D, Dycka J: Prevention and treatment of delayed ischemic dysfunction in patients with aneurysmal subarachnoid hemorrhage. Stroke 21 (Suppl IV):85–89, 1990

    • Search Google Scholar
    • Export Citation
  • 83.

    Thompson SG: Why sources of heterogeneity in meta-analysis should be investigated. Br Med J 309:13511355, 1994 Thompson SG: Why sources of heterogeneity in meta-analysis should be investigated. Br Med J 309:1351–1355, 1994

    • Search Google Scholar
    • Export Citation
  • 84.

    Welty TE: Use of nimodipine for prevention and treatment of cerebral arterial spasm in patients with subarachnoid hemorrhage. Clin Pharmacol 6:940946, 1987 Welty TE: Use of nimodipine for prevention and treatment of cerebral arterial spasm in patients with subarachnoid hemorrhage. Clin Pharmacol 6:940–946, 1987

    • Search Google Scholar
    • Export Citation
  • 85.

    Zelen M: The analysis of several 2×2 contingency tables. Biometrika 58:129137, 1971 Zelen M: The analysis of several 2×2 contingency tables. Biometrika 58:129–137, 1971

    • Search Google Scholar
    • Export Citation

Metrics

All Time Past Year Past 30 Days
Abstract Views 1026 408 23
Full Text Views 475 121 10
PDF Downloads 242 51 5
EPUB Downloads 0 0 0