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Article Excerpt
Abstract: The purpose of this study was to critically analyze the effectiveness of two tools used by nurses to assess neurological status of individuals at risk of developing cerebral vasospasm following aneurysmal subarachnoid hemorrhage due to aneurysm rupture. Early detection of vasospasm provides an opportunity for prompt treatment so that further ischemia or infarction can be prevented. We hypothesized that the National Institutes of Health Stroke Scale would detect symptomatic vasospasm earlier than the standard neurological record currently used in the practice setting of a tertiary care teaching hospital. Thirty participants were entered into the study, and a differential diagnostic process identified 15 with symptomatic vasospasm. Quantitative prospective and retrospective analysis showed that there was no statistical difference between the two scales in early detection of vasospasm. This finding may partially be explained by the clinical similarities between the vasospasm and nonvasospasm groups and by the challenges experienced by nurses in administering the stroke scale. Clinically relevant observations suggested the stroke scale was more effective in the assessment of focal symptoms. Qualitative content analysis of nursing notes also provided insight into clinical findings not captured on either scale regarding generalized changes such as restlessness, impulsiveness, and unusual behavior. This study demonstrates the need to develop a more appropriate tool for early detection of vasospasm.
Subarachnoid hemorrhage (SAH) resulting from aneurysmal rupture occurs in approximately 30,000 persons per year in North America (Mayberg et al., 1994). Of those who experience SAH, 30% will develop vasospasm, a condition that is difficult to treat and associated with a high incidence of morbidity and mortality (Heros & Zervas, 1983). Vasospasm results in diminished cerebral perfusion, which causes ischemia and the potential danger of infarction (Armstrong, 1994; Oropello, Weiner, & Benjamin, 1996). Early detection of vasospasm is therefore critical, and nurses must monitor the patients' neurological status frequently (Armstrong; Warnell, 1996). The Glasgow Coma Scale (GCS), used routinely by nurses, is proficient in detecting general changes in level of consciousness but may not be sensitive enough to capture focal changes (Jennett & Teasdale, 1977).
The primary objective of this study was to determine whether the National Institutes of Health Stroke Scale (NIHSS) is superior in detecting focal and subtle early signs of vasospasm compared to the GCS, which is the standard neurological record (SNR). A second objective was to determine other neurological signs and symptoms of early vasospasm that were not captured in the traditional assessment tool, but were evident in the nursing narratives.
Background
Vasospasm can occur following rupture of an intracranial aneurysm. Various definitions for symptomatic vasospasm can be found in the literature (Oropello et al., 1996; Ullman & Bederson, 1996; Warnell, 1996). Haley et al. (1997) defined vasospasm as (a) having symptoms during the classic time frame (i.e., postrupture 3-14 days), (b) a computed tomography (CT) scan that rules out other causes for neurological decline, and (c) no other identifiable reason for deterioration in condition. They commented that vasospasm may or may not be confirmed by use of angiography or transcranial doppler (Haley et al.).
The onset of vasospasm occurs between 3 and 14 days following rupture (Bell & Kongable, 1996; Powsner, O'Tauma, Jabre, & Melham, 1998). It rarely occurs before 48 hours or after 2 weeks (Armstrong, 1994). Several theories of the pathophysiology of vasospasm exist; however, the exact mechanism remains unknown (Rusy, 1996). What is known is vasospasm can cause ischemia of the cerebral tissues and can lead to infarction and death (Armstrong). Symptoms of vasospasm are variable with each patient and also from hour to hour or minute to minute (Oropello et al., 1996). Generalized symptoms can include lethargy, disorientation, confusion, and decreased level of consciousness (Flynn, 1989; Hickey, 1997). The focal changes that Flynn and Hickey described were speech difficulties, motor weakness or paralysis, and cranial nerve deficits. Haley, Kassell, and Torner (1993) found that vasospasm was the primary cause of disability and death at 3 months for 75% of the population studied. The importance of early detection of vasospasm has been cited in the literature (Barker & Heros, 1990; Powsner et al., 1998). Therefore, ongoing nursing assessments are critical in detecting symptomatic vasospasm (Armstrong, 1994; Hickey, 1997; Rusy 1996).
The GCS was developed to decrease subjectivity in assessing the level of consciousness related to traumatic brain injury (Jennett & Teasdale, 1977). A review of the literature found descriptions of the practical problems...
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