Impact of ICP instability and hypotension on outcome in patients with severe head trauma

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✓ This study describes the relationship between raised intracranial pressure (ICP), hypotension, and outcome from severe head injury. The study is based on information derived from the Traumatic Coma Data Bank where ICP records from a relatively large number of patients were available to help delineate the major factors influencing outcome. From the total data base of 1030 patients, 428 met minimum monitoring duration criteria for inclusion in the present analysis. Outcome was classified according to the Glasgow Outcome Scale score determined at 6 months postinjury. Arrays of comparably defined summary measures describing the patient's course were considered for ICP, blood pressure (BP), central perfusion pressure, and therapy intensity level. For instance, the array of ICP summary descriptors included the proportion of ICP readings greater than x, for x = 0 to 80 mm Hg by increments of 5 mm Hg. A total of 187 candidate summary descriptors were considered. A stepwise ordinal logistic regression was used to select the subset of candidate summary descriptors that best explained the 6-month outcome.

As established previously, age, admission motor score, and abnormal pupils were each highly significant in explaining outcome. Beyond these factors, the proportion of hourly ICP readings greater than 20 mm Hg was next selected and was also highly significant in explaining outcome (p < 0.0001). In addition to the ICP factor, the cutoff point of 20 mm Hg was selected by the procedure as most indicative of outcome. With these four factors modeled, the next selected factor was the proportion of hourly BP readings less than 80 mm Hg. Again, the BP factor was highly significant in explaining outcome (p < 0.0001). As with the ICP factor, the BP cutoff point of 80 mm Hg was objectively selected as most indicative of outcome. In summary, the incidence of mortality and morbidity resulting from severe head trauma is strongly related to raised ICP and hypotension measured during the course of ICP management. Moreover, these ICP and BP factors provide a better indication of outcome than the similarly defined factors of central perfusion pressure or therapy intensity level.

Article Information

Address reprint requests to: Anthony Marmarou, Ph.D., Medical College of Virginia, P.O. Box 508, MCV Station, Richmond, Virginia 23298–0001.

© AANS, except where prohibited by US copyright law.

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Figures

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    Histogram showing each patient's proportion of intracranial pressure (ICP) measurements greater than 20 mm Hg, Eighty of the 428 patients had no ICP measurements greater than 20 mm Hg. The solid bars represent patients with no missing data for any measures used in this analysis. The hatched bars represent patients who had missing data for one or more analysis variables.

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    Histogram showing each patient's proportion of blood pressure (BP) measurements below 80 mm Hg. Sixty-seven of the 428 patients never evidenced hypotension. The solid bars represent patients with no missing data for any measures used in this analysis. The hatched bars represent patients who had missing data for one or more analysis variables.

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    Plots of estimated outcome probability versus proportion of intracranial pressure measurements more than 20 mm Hg (p(ICP > 20)) for each outcome group. To simplify the presentation, the other modeled factors were fixed at the following values: age = 30 years, admission motor score = 3 (flexion), abnormal pupils = 1, and proportion of blood pressure measurements less than 80 mm Hg (p(BP < 80)) = 0. Ninety-five percent asymptotic confidence bands are plotted around each curve.

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    Three-dimensional surface of estimated outcome probability versus the proportion of intracranial pressure (ICP) measurements greater than 20 mm Hg (p(ICP > 20)) and the proportion of blood pressure measurements less than 80 mm Hg (p(BP < 80)) for the vegetative/dead outcome group. To simplify the presentation, the other modeled factors were fixed at the following values: age = 30 years, admission motor score = 3 (flexion), and abnormal pupils = 1. The substantial effect of hypotension is readily evident from the front-to-back upward sloping of the surface. The impact of ICP elevation is apparent from the right-to-left upward sloping of the surface.

References

  • 1.

    Alberico AMWard JDChoi SCet al: Outcome after severe head injury. Relationship to mass lesions, diffuse injury, and ICP course in pediatric and adult patients. J Neurosurg 67:6486561987Alberico AM Ward JD Choi SC et al: Outcome after severe head injury. Relationship to mass lesions diffuse injury and ICP course in pediatric and adult patients. J Neurosurg 67:648–656 1987

    • Search Google Scholar
    • Export Citation
  • 2.

    Bartolucci AAFraser MD: Comparative step-up and composite tests and selecting prognostic indicators associated with survival. Biomedical J 19:4374481977Bartolucci AA Fraser MD: Comparative step-up and composite tests and selecting prognostic indicators associated with survival. Biomedical J 19:437–448 1977

    • Search Google Scholar
    • Export Citation
  • 3.

    Becker DPMiller JDWard JDet al: The outcome from severe head injury with early diagnosis and intensive management. J Neurosurg 47:4915021977Becker DP Miller JD Ward JD et al: The outcome from severe head injury with early diagnosis and intensive management. J Neurosurg 47:491–502 1977

    • Search Google Scholar
    • Export Citation
  • 4.

    Chestnut RMMarshall LF: Analysis of the role of secondary brain injury in determining outcome from severe head injury. J Neurosurg 72:360A1990 (Abstract)Chestnut RM Marshall LF: Analysis of the role of secondary brain injury in determining outcome from severe head injury. J Neurosurg 72:360A 1990 (Abstract)

    • Search Google Scholar
    • Export Citation
  • 5.

    Choi SCNarayan RKAnderson RLet al: Enhanced specificity of prognosis in severe head injury. J Neurosurg 69:3813851988Choi SC Narayan RK Anderson RL et al: Enhanced specificity of prognosis in severe head injury. J Neurosurg 69:381–385 1988

    • Search Google Scholar
    • Export Citation
  • 6.

    Choi SCWard JDBecker DP: Chart for outcome prediction in severe head injury. J Neurosurg 59:2942971983Choi SC Ward JD Becker DP: Chart for outcome prediction in severe head injury. J Neurosurg 59:294–297 1983

    • Search Google Scholar
    • Export Citation
  • 7.

    Eisenberg HMCayard CPapanicolaou Aet al: The effects of three potentially preventable complications on outcome after severe closed head injury in Ishii SNagai HBrock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag1983 pp 549553Eisenberg HM Cayard C Papanicolaou A et al: The effects of three potentially preventable complications on outcome after severe closed head injury in Ishii S Nagai H Brock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag 1983 pp 549–553

    • Search Google Scholar
    • Export Citation
  • 8.

    Foulkes MAEisenberg HMJane JAet al: The Traumatic Coma Data Bank: design, methods, and baseline characteristics. J Neurosurg 75 (Suppl):S8S131991Foulkes MA Eisenberg HM Jane JA et al: The Traumatic Coma Data Bank: design methods and baseline characteristics. J Neurosurg 75 (Suppl):S8–S13 1991

    • Search Google Scholar
    • Export Citation
  • 9.

    Gaab MRHaubitz I: Intracranial pressure, primary/secondary brain stem injury and prognosis in cerebral trauma in Ishii SNagai HBrock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag1983 pp 501531Gaab MR Haubitz I: Intracranial pressure primary/secondary brain stem injury and prognosis in cerebral trauma in Ishii S Nagai H Brock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag 1983 pp 501–531

    • Search Google Scholar
    • Export Citation
  • 10.

    Harrell FELee KL: The practical value of logistic regression. Proceedings of the Tenth Annual SAS Users Group International Conference. Cary, NC: SAS Institute1985 pp 10311036Harrell FE Lee KL: The practical value of logistic regression. Proceedings of the Tenth Annual SAS Users Group International Conference. Cary NC: SAS Institute 1985 pp 1031–1036

    • Search Google Scholar
    • Export Citation
  • 11.

    Harrell FELee KLCaliff RMet al: Regression modelling strategies for improved prognostic prediction. Stat Med 3:1431521984Harrell FE Lee KL Califf RM et al: Regression modelling strategies for improved prognostic prediction. Stat Med 3:143–152 1984

    • Search Google Scholar
    • Export Citation
  • 12.

    Janny PJouan JPGourgand Met al: A statistical approach to long-term monitoring of intracranial pressure in Brock MDietz H (eds): Intracranial Pressure. Berlin: Springer-Verlag1972 pp 5964Janny P Jouan JP Gourgand M et al: A statistical approach to long-term monitoring of intracranial pressure in Brock M Dietz H (eds): Intracranial Pressure. Berlin: Springer-Verlag 1972 pp 59–64

    • Search Google Scholar
    • Export Citation
  • 13.

    Jennett BBond M: Assessment of outcome after severe damage. A practical scale. Lancet 1:4804841975Jennett B Bond M: Assessment of outcome after severe damage. A practical scale. Lancet 1:480–484 1975

    • Search Google Scholar
    • Export Citation
  • 14.

    Marmarou AAnderson RLWard JDet al: NINDS Traumatic Coma Data Bank: intracranial pressure monitoring methodology. J Neurosurg 75 (Suppl):S21S271991Marmarou A Anderson RL Ward JD et al: NINDS Traumatic Coma Data Bank: intracranial pressure monitoring methodology. J Neurosurg 75 (Suppl):S21–S27 1991

    • Search Google Scholar
    • Export Citation
  • 15.

    Marshall LFSmith RWShapiro HM: The outcome with aggressive treatment in severe head injuries. Part I: The significance of intracranial pressure monitoring. J Neurosurg 50:20251979Marshall LF Smith RW Shapiro HM: The outcome with aggressive treatment in severe head injuries. Part I: The significance of intracranial pressure monitoring. J Neurosurg 50:20–25 1979

    • Search Google Scholar
    • Export Citation
  • 16.

    Maset ALMarmarou AWard JDet al: Pressure-volume index in head injury. J Neurosurg 67:8328401987Maset AL Marmarou A Ward JD et al: Pressure-volume index in head injury. J Neurosurg 67:832–840 1987

    • Search Google Scholar
    • Export Citation
  • 17.

    McGraw CPHoward GO'Connor C: Outcome associated with management based on ICP monitoring in Ishii SNagai HBrock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag1983 pp 558561McGraw CP Howard G O'Connor C: Outcome associated with management based on ICP monitoring in Ishii S Nagai H Brock M (eds): Intracranial Pressure V. Berlin: Springer-Verlag 1983 pp 558–561

    • Search Google Scholar
    • Export Citation
  • 18.

    Miller JDBecker DPWard JDet al: Significance of intracranial hypertension in severe head injury. J Neurosurg 47:5035161977Miller JD Becker DP Ward JD et al: Significance of intracranial hypertension in severe head injury. J Neurosurg 47:503–516 1977

    • Search Google Scholar
    • Export Citation
  • 19.

    Miller JDButterworth JFGudeman SKet al: Further experience in the management of severe head injury. J Neurosurg 54:2892991981Miller JD Butterworth JF Gudeman SK et al: Further experience in the management of severe head injury. J Neurosurg 54:289–299 1981

    • Search Google Scholar
    • Export Citation
  • 20.

    Miller JDSweet RCNarayan Ret al: Early insults to the injured brain. JAMA 240:4394421978Miller JD Sweet RC Narayan R et al: Early insults to the injured brain. JAMA 240:439–442 1978

    • Search Google Scholar
    • Export Citation
  • 21.

    Narayan RKGreenberg RPMiller JDet al: Improved confidence of outcome prediction in severe head injury. A comparative analysis of the clinical examination, multimodality evoked potentials, CT scanning, and intracranial pressure. J Neurosurg 54:7517621981Narayan RK Greenberg RP Miller JD et al: Improved confidence of outcome prediction in severe head injury. A comparative analysis of the clinical examination multimodality evoked potentials CT scanning and intracranial pressure. J Neurosurg 54:751–762 1981

    • Search Google Scholar
    • Export Citation
  • 22.

    Nordby HKGunnerød N: Epidural monitoring of the intracranial pressure in severe head injury characterized by non-localizing motor response. Acta Neurochir 74:21261985Nordby HK Gunnerød N: Epidural monitoring of the intracranial pressure in severe head injury characterized by non-localizing motor response. Acta Neurochir 74:21–26 1985

    • Search Google Scholar
    • Export Citation
  • 23.

    Pitts LHKaktis JVJuster Ret al: ICP and outcome in patients with severe head injury in Shulman KMarmarou AMiller JDet al (eds): Intracranial Pressure IV. Berlin: Springer-Verlag1980 pp 59Pitts LH Kaktis JV Juster R et al: ICP and outcome in patients with severe head injury in Shulman K Marmarou A Miller JD et al (eds): Intracranial Pressure IV. Berlin: Springer-Verlag 1980 pp 5–9

    • Search Google Scholar
    • Export Citation
  • 24.

    Price JEMurray A: The influence of hypoxia and hypotension on recovery from head injury. Br J Accid Surg 3:2182241972Price JE Murray A: The influence of hypoxia and hypotension on recovery from head injury. Br J Accid Surg 3:218–224 1972

    • Search Google Scholar
    • Export Citation
  • 25.

    Rosner MJDaughton S: Cerebral perfusion pressure management in head injury. J Trauma 30:9339411990Rosner MJ Daughton S: Cerebral perfusion pressure management in head injury. J Trauma 30:933–941 1990

    • Search Google Scholar
    • Export Citation
  • 26.

    Saul TGDucker TB: Effect of intracranial pressure monitoring and aggressive treatment on mortality in severe head injury. J Neurosurg 56:4985031982Saul TG Ducker TB: Effect of intracranial pressure monitoring and aggressive treatment on mortality in severe head injury. J Neurosurg 56:498–503 1982

    • Search Google Scholar
    • Export Citation
  • 27.

    Smith HPKelly DL JrMcWhorter JMet al: Comparison of mannitol regimens in patients with severe head injury undergoing intracranial monitoring. J Neurosurg 65:8208241986Smith HP Kelly DL Jr McWhorter JM et al: Comparison of mannitol regimens in patients with severe head injury undergoing intracranial monitoring. J Neurosurg 65:820–824 1986

    • Search Google Scholar
    • Export Citation
  • 28.

    Stuart GGMerry GSSmith JAet al: Severe head injury managed without intracranial pressure monitoring. J Neurosurg 59:6016051983Stuart GG Merry GS Smith JA et al: Severe head injury managed without intracranial pressure monitoring. J Neurosurg 59:601–605 1983

    • Search Google Scholar
    • Export Citation
  • 29.

    Teasdale GJennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 2:81841974Teasdale G Jennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 2:81–84 1974

    • Search Google Scholar
    • Export Citation
  • 30.

    Tsutsumi HIde KMizutani Tet al: The relationship between intracranial pressure, cerebral perfusion pressure and outcome in head injured patients: the critical level of cerebral perfusion pressure in Miller JDTeasdale GMRowan JOet al (eds): Intracranial Pressure VI. Berlin: Springer-Verlag1986 pp 661666Tsutsumi H Ide K Mizutani T et al: The relationship between intracranial pressure cerebral perfusion pressure and outcome in head injured patients: the critical level of cerebral perfusion pressure in Miller JD Teasdale GM Rowan JO et al (eds): Intracranial Pressure VI. Berlin: Springer-Verlag 1986 pp 661–666

    • Search Google Scholar
    • Export Citation

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