APPROXIMATELY 25,000 to 30,000 persons experience

Transcription

1 678 Functional Outcome After Inpatient Rehabilitation in Persons With Subarachnoid Hemorrhage Michael W. O Dell, MD, Thomas K. Watanabe, MD, Steven T. De Roos, MD, Christopher Kager, MD ABSTRACT. O Dell MW, Watanabe TK, De Roos ST, Kager C. Functional outcome after inpatient rehabilitation in persons with subarachnoid hemorrhage. Arch Phys Med Rehabil 2002;83: Objectives: To describe inpatient rehabilitation outcome in persons with nontraumatic subarachnoid hemorrhage (SAH) and to explore the predictive capacity of acute measures of SAH severity and demographic and disease variables. Design: Retrospective withdescriptive and relational analyses. Setting: Free-standing, acute, inpatient brain injury rehabilitation unit. Participants: Forty-two consecutive persons withnontraumatic SAH and for whom complete data were available were studied. Mean age of the group was 56.5 years, mean acute hospital stay was 26.2 days, and 60% were women. Over 40% experienced rupture of an anterior communicating artery aneurysm. The time from injury to rehabilitation admission varied from 11 to 227 days (mean, 43.8d). Interventions: Not applicable. Main Outcome Measure: Change in instrument scores, home discharge rate, and rehabilitation length of stay (LOS.) Results: The mean admission and discharge scores were 57.7 and 85.5 points, respectively. There was a 27.8-point mean change in score over a 24.1-day mean rehabilitation LOS for a efficiency (points/day) of Over 80% of the sample was discharged home. No demographic or disease characteristic variables, including acute severity measures, were statistically significant predictors of outcome. Conclusions: Functional gains during inpatient rehabilitation made in this group of 42 persons with SAH are in line with earlier studies. Our rehabilitation LOS is the shortest reported among 4 studies to date and is probably a reflection of managed care in the United States. A small sample, uneven cell sizes, and variability of patients might have contributed to a lack of significant findings. Future study should explore the prediction of rehabilitation outcome using larger sample sizes and longer follow-up periods. From the Department of Physical Medicine and Rehabilitation, Long Island Jewish Medical Center, New Hyde Park, NY (O Dell); Regional Center for Brain Injury Rehabilitation, Southside Hospital, Bay Shore, NY (O Dell); Departments of Physical Medicine and Rehabilitation (Watanabe, De Roos) and Neurosurgery (Kager), University of Cincinnati College of Medicine, Cincinnati, OH; and The Drake Center, Cincinnati, OH (Watanabe). De Roos is now affiliated withmary Free Bed Hospital, Grand Rapids, MI. O Dell is now affiliated withthe New York Weill Cornell Center, New York, NY. Accepted in revised form May 21, Presented in part at the American Academy of Physical Medicine and Rehabilitation s Annual Assembly, November 6-7, 1998, Seattle, WA. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated. Reprint requests to Michael W. O Dell, MD, New York Weill Cornell Center, 525 E 68thSt, F1811, New York, NY 10021, mio2005@med.cornell.edu /02/ $35.00/0 doi: /apmr Key Words: Disabled persons; Outcome assessment (health care); Rehabilitation; Subarachnoid hemorrhage by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation APPROXIMATELY 25,000 to 30,000 persons experience subarachnoid hemorrhage (SAH) from ruptured cerebral aneurysms eachyear in the United States. 1,2 Half of these individuals die before or during their acute hospitalization, and as many as 50% of those remaining will experience residual physical and/or cognitive impairments. 2,3 The severity of the residual neurologic sequelae ranges from mild cranial nerve dysfunction to profound amnesia and personality changes 4 to vegetative state. 5 The incidence of clinically significant cognitive deficits may be much higher than previously thought, 6,7 even among those classified as having a good outcome on the Glasgow Outcome Scale (GOS). 8 Unlike other vascular etiologies of acquired brain injury, the incidence of cerebral aneurysms has not decreased significantly over the past few decades 1,3 and is greater than the incidence of multiple sclerosis, intracranial gliomas, or traumatic spinal cord injury. 1,9 It is somewhat unclear whether mortality has improved. 2,10 Only recently has there been substantial discussion of the rehabilitation management and functional outcomes in this population. 4,11-17 Unlike the Glasgow Coma Scale in traumatic brain injury, 18 only 2 studies 16,17 relating acute severity measures in nontraumatic SAH to rehabilitation outcome have been published, both using the same cohort at different times postinjury. As the field of brain injury rehabilitation matures, researchers are exploring how specific etiologies or subtypes of acquired brain injury might influence functional outcomes. Gaining an understanding of how acute severity measures relate to rehabilitation outcome also may assist in prognostication and patient selection. The purpose of the present study was to describe rehabilitation outcomes in a group of patients admitted to an acute inpatient brain injury rehabilitation program following neurosurgical treatment of nontraumatic SAH. In addition, the relationship between rehabilitation outcome and acute measures of severity, as well as other variables, is explored. METHODS Records of admissions to The Drake Center Inc inpatient brain injury rehabilitation unit in Cincinnati, OH, were retrospectively reviewed searching for patients with the admission diagnosis of nontraumatic SAH. Admission criteria to the unit included age over 15 years, medical stability, and expectation of benefit from intensive rehabilitation. For in-county residents, there were no financial restrictions. The years of the review were from 1993 to Once identified, medical charts and transfer records were then reviewed for the following information when available: age; gender; history of cigarette smoking; acute hospital length of stay (LOS); time from injury to rehabilitation admission; side and location of the ruptured cerebral artery or arteriovenous malformation (AVM); acute care transfer; and the presence of swallowing, language, and/or motor

2 REHABILITATION IN SUBARACHNOID HEMORRHAGE, O Dell 679 Score Table 1: Hunt and Hess Clinical Grading Scale 19 deficits at admission. Records were also searched for documentation of SAH complications including cerebral arterial vasospasm, seizures, and hydrocephalus with and without placement of a ventriculoperitoneal (VP) shunt. If no documentation was found, the patient was coded as not having that complication. Assessment of the patient s initial neurologic and neuroradiographic status according to Hunt and Hess scores 19,20 or Fisher grades 21 was sought. The Hunt and Hess scale was developed to assess surgical mortality risk based on patient status at presentation. In it, patients are rated from 1 to 5 based on their neurologic and mental status (table 1). Fisher grade scores are based on the amount of subarachnoid blood observed on initial brain computed tomography (table 2) and correlate with the risk of cerebral vasospasm. In the present study, in approximately 50% of assigned cases, Hunt and Hess scores and Fisher grades were estimated by a neurosurgeon (CK), who used available data from acute care records and initial radiographs. Functional status at admission to and discharge from inpatient rehabilitation was determined by using the instrument assigned by a -certified, interdisciplinary team. The validity and reliability of the have been extensively documented Except for an emphasis on change rather than admission and discharge scores, our data analysis is similar to an analysis made previously by Dombovy et al. 16 Disposition at discharge and rehabilitation LOS were noted. During rehabilitation, the patients received at least 3 hours of rehabilitation therapies (occupational, physical, speech, recreational) eachday in an accredited program. Every patient was evaluated by both physiatrists and neuropsychologists, and progress was reviewed by the rehabilitation team on a weekly basis. Table 2: Fisher Grades for Subarachnoid Hemorrhage Grade Description 1 No blood detected 2 Diffuse deposition or thin layer of blood, with all vertical layers of blood less than 1-mm thick 3 Localized clots or vertical layers of blood 1mm or greater in thickness, or both 4 Diffuse or no subarachnoid blood but with intracerebral or intraventricular clots Reprinted with permission. 21 Description 1 Asymptomatic or minimal headache and slight nuchal rigidity 2 Moderate to severe headache, nuchal rigidity, no neurologic deficit (other than cranial nerve palsy) 3 Drowiness, confusion, mild focal deficits 4 Stupor, moderate to severe hemiparesis, possible early decerebrate rigidity and vegetative disturbances 5 Deep coma, decerebrate rigidity, moribund appearance Reprinted with permission of the American Association of Neurological Surgeons. 19 Table 3: Demographic Characteristics (N 42) Parameter Mean Median Range SD Age (y) Time from injury to rehabilitation admission (d) Acute hospital LOS (d) N % Gender Male Female Location of cerebral lesion ACoA PCO MCA BAS ACA ICA AVM Other Abbreviations: PCO, posterior communicatingartery; MCA, middle cerebral artery; BAS, basilar artery; ACA, anterior cerebral artery; ICA, internal carotid artery. Statistical Analysis Descriptive statistics include frequency distribution for categoric variables and means, medians, ranges, and standard deviations (SDs) for continuous variables. Significant differences in change between selected subgroups were determined by using 1 of 2 nonparametric tests: Mann-Whitney U statistic (for 2 groups) or Kruskal-Wallis 1-way analysis of variance procedure (for more than 2 groups). To determine significant differences between rehabilitation LOS in patients admitted before or after 80 days from SAH, a 2-sample t test was used. All analyses were completed by using Statistix for Windows. a RESULTS Sample Characteristics A total of 44 patients withnontraumatic SAH were identified, 42 (95%) of whom had complete demographic and outcome data. Table 3 shows the sample s demographic and disease characteristics. The distribution of time from injury to rehabilitation admission was quite skewed, as reflected by a mean of 43.8 and median of 22 days. Approximately 86% of the patients were admitted to inpatient rehabilitation within 60 days of injury. However, because of their nursing home or subacute rehabilitation stays before acute rehabilitation, 2 patients were approximately 80 days and 4 patients longer than 120 days from injury. Omitting these outlying 6 cases decreases the mean time from injury to rehabilitation admission to 26.8 days (median SD, 19 15d). A large proportion (42.9%) of patients had experienced rupture of an anterior communicating artery (ACoA) aneurysm, withthe remainder at a variety of other anatomic locations. One patient (2.3%) experienced an AVM requiring surgical intervention. Thirty-eight percent had right-sided and 29% left-sided lesions, with the side indeterminate in one third of cases. Three quarters of the group had a history of cigarette smoking. A variety of impairments were documented withover 60% showing some degree of strength deficits. Fifty-seven percent had expressive and 43% reception language deficits and 40% some degree of dysphagia at rehabilitation admission. Functional Outcome at Discharge Functional outcome parameters are outlined in table 4. The group achieved a mean gain of 27.8 points (median, 29;

3 680 REHABILITATION IN SUBARACHNOID HEMORRHAGE, O Dell Table 4: RehabilitationOutcome Measures (N 42) Measure Mean Median Range SD Admission Discharge Change in to Rehabilitation LOS (d) Discharge Status N % Home* Nursinghome Other * Three patients required transfer to acute care before discharge to home. Four patients required transfer to acute care before discharge to a nursinghome. range, 2 to 63) over an average rehabilitation LOS of days (range, 5 58d), for a efficiency of Of the 42 admissions, 7 patients (16.6%) experienced complications requiring transfer to acute care, 6 of whom returned to complete a course of rehabilitation. Among the 6 transfers who returned to the unit, 2 were eventually discharged home and 4 to a nursing home. Of the 35 admissions not requiring acute transfer, 32 were discharged home and 3 to a nursing home. In total, just over 80% of patients were eventually discharged home. Predictors of Functional Outcome Table 5 outlines the admission, discharge, and change in scores by selected demographic and disease subgroups. Although our analyses are limited by relatively small cell sizes in some cases, no demographic or disease variable influenced outcome as defined by gain, although in a few instances the raw gains were modestly different. In terms of age, the greatest gains and discharge functional levels were achieved in the youngest group (30 40y, n 9). Interestingly, the second largest mean gain was made by the oldest age group ( 70y, n 5). Change scores for gender were virtually identical. The greatest mean gain by lesion location was 34.4 points by the other group (n 8) and the least gain of 21.7 points by the basilar group (n 4). ACoA aneurysms, the largest subgroup (n 18), posted an intermediate mean gain of 27.7 points. Striking is the middle cerebral artery group (n 5), with both the lowest admission and discharge scores despite robust gains. Complications of SAH had an inconsistent relationship to functional outcome. Althoughpresenting withslightly lower scores at admission, the presence of hydrocephalus or a VP shunt did not appear to have a detrimental impact on functional gain and, in fact, had a modestly positive (but not statistically significant) effect. Interestingly, admission, discharge, and gain scores were all higher in the small group of 8 patients withseizures. Patients withvasospasm showed a mean gain that was 7 points lower than those without documented vasospasm. Because of several missing data, no analysis was completed for side of lesion. As in the other categories, we observed no clear impact between initial severity measures and functional gain (see table 5). The 8 patients classified as Hunt and Hess score 1 were admitted and discharged with the highest scores among the Hunt and Hess groups but showed the least functional gain at a mean of 25.9 points. No clear patterns emerged among admission, discharge, or change scores in the remaining Hunt and Hess categories. Likewise, no clear patterns relating Fisher grades and change were noted. DISCUSSION The present study contributes to a recently developed and growing literature addressing functional outcome after inpatient rehabilitation in persons with SAH from cerebral aneurysm or AVM. Survivors of SAH often manifest impairments, usually cognitive, not typically recognized when the GOS is used to measure outcome. 8 This is particularly true in the case of ACoA aneurysms. 4 In older rehabilitation studies, SAH was likely to be grouped with strokes or hemorrhagic strokes, at best. 14 The SAH patients younger age, greater vocational needs, and combination of bothdiffuse and focal pathology may warrant a distinction from thrombotic and ischemic strokes and intracerebral hemorrhage. 11,16,17 Recent data suggest a trend toward better inpatient rehabilitation outcome in SAH compared withage, gender, and side-of-lesion matched ischemic strokes. 15 In terms of demographics and outcome, our data are quite consistent with 3 previously published studies using rehabilitation-based samples, which are summarized in table 6. Age Table 5: Functional Status for Selected Subgroups Parameter* n Mean Admission Mean Discharge Mean Change SD Age (y) Gender Male Female Lesion location ACoA PCO MCA BAS Other Hunt and Hess score (n 31) Fisher grade (n 31) Hydrocephalus Yes No VP shunt Yes No Seizures Yes No Vasospasm Yes No * No group comparison was statistically significant. There were no subjects in the Hunt and Hess score 5 group.

4 REHABILITATION IN SUBARACHNOID HEMORRHAGE, O Dell 681 Table 6: RehabilitationOutcome insubarachnoid Hemorrhage: A Comparisonof 4 Studies Authors (y) N Lesion Location Mean Age (y) Male (%) A-LOS (d) Adm Dis Eff Rehabil LOS Home Dis (%) Clinchot ( ) 80 35% ACoA * % MCA 19% PCA Westerkam ( ?) 41 Data not provided Dombovy ( ) 80 25% PCA % ACA 9% ACoA 9% AVM O Dell and Watanabe ( ) 42 43% ACoA % PCO 12% MCA 2.4% AVM Abbreviations: A-LOS, acute care LOS; Adm, admission score; Dis, discharge score;, change in score; Eff, efficiency; Rehabil, rehabilitation; Home Dis, discharge to home. * Indirectly calculated from data provided. and gender distributions, admission and change scores, and discharge trends are relatively consistent. The suggestion of a chronologic reduction in rehabilitation LOS among the studies may reflect trends in health care delivery and financing. A lower incidence of internal carotid artery and higher incidence of ACoA aneurysms are seen in these rehabilitation cohorts compared with the neurosurgical literature. 3,25-30 Perhaps the outcomes in internal carotid artery aneurysms are generally favorable enough that inpatient rehabilitation is unnecessary. Although disputed by some investigators, 31 the suggestion that persons with ACoA aneurysms are more apt to experience amnesia and personality changes (potentially making home discharge problematic) may contribute to its overrepresentation in inpatient rehabilitation. 4 With regard to the present study, the youngest age group (30 40y) had the greatest mean gain at 38.1, with the other 4 age groups showing similar gains and mean rehabilitation LOS (data not shown). This contrasts, for uncertain reasons, with neurosurgical studies that have shown a strong negative correlation between outcome and advancing age. 29 Functional gains by gender were virtually identical. Consistent withdombovy et al 16 and Clinchot et al, 13 aneurysm location had little impact on functional gain, although these data were limited by small cell sizes. Our findings do not confirm that SAH complications adversely impact outcome, in contrast to data from most neurosurgical cohorts. 7,26,27 Admission functional status and change were inconsistent according to documentation of hydrocephalus, VP shunt placement, seizures, or cerebral vasospasm (see table 5). Likewise, we found no significant differences either in time from injury to rehabilitation admission or rehabilitation LOS among patients withor without documented complications of SAH (data not shown). Because the present study relied on a retrospective review of medical records, our lack of a standardized, prospective definition of SAH complications could have impacted the accuracy of our classification. Furthermore, our observations may be biased vis-à-vis neurosurgical cohorts because persons who died from SAH complications or persons withprofound deficits as a result of SAH would not be candidates for inpatient rehabilitation and would not have contributed to our sample. It should be noted that Dombovy, 16 by using a sample twice that of the present study, found that only the presence of hydrocephalus was predictive of outcome (discharge, in their case) and even then only at a modest level (P.05). Our results are disappointing regarding SAH acute severity measures ability to predict rehabilitation outcome. With the exception of Hunt and Hess score of 1, even mean admission functional status failed to group according to expected trends (ie, lower functional status withgreater severity). It is of some concern that only 31 (74%) of the sample had complete data on severity, suggesting the possibility of bias. The 31 patients with scores were not statistically different from the 11 without scores withrespect to age, time from injury to rehabilitation admission, rehabilitation LOS, or admission score. Uneven cell sizes and the possibility a ceiling effect of the in Hunt and Hess score 1 may have also contributed to a poor predictive capacity. If our present data are valid, Hunt and Hess scores may predict life and deathoutcomes but not more subtle constructs suchas physical and cognitive disability. Likewise, Fisher grades showed no consistent relationship to outcome. It should be noted that, Dombovy 16 by using data from 80 of 103 eligible patients, also failed to show a convincing relationship between rehabilitation outcome and Hunt and Hess scores. Several limitations to the present study s sample and analysis methods should be noted. Because of time spent in less intense rehabilitation venues, our patients had a time from injury to rehabilitation admission that was quite variable (see table 3). However, the mean LOS and gains were similar between the 6 patients whose time was greater than 80 days from injury versus those with an interval less than 80 days (29.9 vs 23.3d, 27.1 vs 27.9 points, respectively). This finding suggests a minimal impact on our results. As mentioned, the small sample size and small or uneven cell sizes may have contributed to a lack of statistically significant differences in some analyses. In other cases, the may not have been sensitive enoughto detect more subtle differences between groups (particularly if the differences were primarily cognitive in nature). Our outcomes cannot be generalized beyond an acute rehabilitation setting (perhaps not beyond a subspecialty brain injury rehabilitation unit) and cannot be compared with neurosurgical cohorts. Because no comparison group was included, no comment can be made regarding the efficacy of inpatient rehabilitation in persons with SAH. CONCLUSION We observed a mean gain of 27.8 points over a mean rehabilitation stay of 24.1 days in a group of 42 persons with SAH caused primarily by ruptured cerebral aneurysms requiring neurosurgical intervention. Approximately 80% of the

5 682 REHABILITATION IN SUBARACHNOID HEMORRHAGE, O Dell group eventually returned home, consistent with earlier studies. On the basis of these observations, we believe inpatient rehabilitation represents an appropriate option in selected patients for care after aneurysm surgery. We were unable to identify specific demographic variables or disease characteristics that predicted outcome. On the basis of our data, increased age, time from injury, and severe injury (on the basis of acute care measures) should not necessarily preclude a trial of inpatient rehabilitation in an otherwise appropriate candidate. Future research should explore the impact of SAH complications and lesion location on rehabilitation outcome by using larger sample sizes, longer follow-up periods, and more sensitive assessment instruments. In addition, measurement of quality of life and handicap in the community setting and prediction of those outcomes by using parameters available in a rehabilitation setting would be extremely valuable to clinicians and patients alike. References 1. Schievink WI. Intracranial aneurysms. N Engl J Med 1997;336: 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. Circulation 1994;90: Meyer FB, Morita A, Puumala MR, Nichols DA. Medical and surgical management of intracranial aneurysms. Mayo Clin Proc 1995;70: DeLuca J, Diamond BJ. Aneurysm of the anterior communicating artery: a review of neuroanatomical and neuropsychological sequelae. J Clin Exp Neuropsychol 1995;17: Multi-Society Task Force on the Persistent Vegetative State. Medical aspects of the persistent vegetative state (part II). 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