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Cognitive impairments in recreational SCUBA divers with decompression illness
Abstracts from the 19th Annual Meeting
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ough neuropsychological evaluation in anoxic/hypoxic brain injury. In cases where patients are not functioning adequately in a work environment, neurological evaluation even with neuroimaging cannot fully capture cognitive impairment. A briefer neuropsychological battery, as is often necessary in the managed care environment, cannot reveal the range of deficits seen in a more comprehensive battery. These findings are reviewed in the context of the literature on anoxic/hypoxic brain injury.
Hopkins, R. O., Weaver, L. K., & Gale, S. D. Cognitive Impairments in Recreational SCUBA Divers with Decompression Illness. Neuropsychological tests are not routinely administered to patients following Decompression Illness (DCI), especially in cases in which there are no overt cognitive complaints or suspicion of cognitive impairments (Curley et al., 1994). Since DCI is caused by intravascular and occasionally tissue nitrogen bubbles, it is hypothesized that brain injury might result from DCI. To support this hypothesis, studies indicate that recreational divers with DCI may experience cognitive deficits (Curley et al., 1988; Dear et al., 1994) including impaired memory, attention, dysarthria, and psychosis (Elliott, 1994). Since June 1989, we have seen 39 cases of DCI in recreational divers. By retrospective chart review, medical records, and results from a neuropsychological screening battery were analyzed. Patients were treated with HBO: if they had signs and symptoms of DCI, an abnormal neurological exam or abnormal neuropsychological test results. Twentyseven patients were treated with HBO2 treatment (2 refused treatment). Twenty-nine patients were tested prior to HBOe and 10 patients were treated after the first HBO2 treatment (all data are reported as mean _ standard deviation, range). Thirteen percent of the patients lost consciousness. Risk factors for the development of DCI include: age > 40, short surface interval, omitting decompression stops, rapid ascent, obesity, lack of sleep prior to diving, and alcohol intake within 24 hours of diving. Six of the patients had one risk factor for DCI and 15 of the patients had more than one risk factor. The patients' age was 32.6 ± 9 (19-57), number of dives 6.1 __+5.1 (1-24), greatest depth in feet 84.2 _+ 7.7 (25-200). 49% of patients received treatment within 24 hours and 51% greater than 24 hours. Patients received an average of 4.4 ± 5.1 (1-18) HBO: treatments. At hospital admission, 46% of patients reported cognitive complaints but 67% had abnormal neuropsychological testing. The cognitive impairments include: speed of processing (37%), memory (24%), attention/concentration (32%), and visuoconstruction problems (42%). Following the last HBO2 treatment, 40% of patients' test scores were within the normal range and 60% continued to exhibit cognitive impairments. The following conclusions are drawn: (a) Recreational divers with DCI are at risk for developing cognitive impairments. (b) Divers are frequently unaware of their cognitive impairments. (c) Cognitive impairments may indicate brain injury. (d) Divers should be educated, follow dive profiles and avoid known risk factors to prevent DCI and its sequelae. (e) The magnitude and duration of the residual cognitive impairments is unknown. Divers who experience symptoms of DCI while/after diving should seek prompt evaluation and treatment. We recommend that divers with DCI have neuropsychological testing to assess cognitive function. Perna, R., Durgin, D., & Geiler, S. E. Complaints of Memory Dysfunction: How Much is Related to Compromised Attention. Many individuals who have experienced a traumatic brain injury and are presenting with complaints of impaired short-term memory, actually have primary attentional impairments or problems in information processing with secondary memory impairments. If
775
ough neuropsychological evaluation in anoxic/hypoxic brain injury. In cases where patients are not functioning adequately in a work environment, neurological evaluation even with neuroimaging cannot fully capture cognitive impairment. A briefer neuropsychological battery, as is often necessary in the managed care environment, cannot reveal the range of deficits seen in a more comprehensive battery. These findings are reviewed in the context of the literature on anoxic/hypoxic brain injury.
Hopkins, R. O., Weaver, L. K., & Gale, S. D. Cognitive Impairments in Recreational SCUBA Divers with Decompression Illness. Neuropsychological tests are not routinely administered to patients following Decompression Illness (DCI), especially in cases in which there are no overt cognitive complaints or suspicion of cognitive impairments (Curley et al., 1994). Since DCI is caused by intravascular and occasionally tissue nitrogen bubbles, it is hypothesized that brain injury might result from DCI. To support this hypothesis, studies indicate that recreational divers with DCI may experience cognitive deficits (Curley et al., 1988; Dear et al., 1994) including impaired memory, attention, dysarthria, and psychosis (Elliott, 1994). Since June 1989, we have seen 39 cases of DCI in recreational divers. By retrospective chart review, medical records, and results from a neuropsychological screening battery were analyzed. Patients were treated with HBO: if they had signs and symptoms of DCI, an abnormal neurological exam or abnormal neuropsychological test results. Twentyseven patients were treated with HBO2 treatment (2 refused treatment). Twenty-nine patients were tested prior to HBOe and 10 patients were treated after the first HBO2 treatment (all data are reported as mean _ standard deviation, range). Thirteen percent of the patients lost consciousness. Risk factors for the development of DCI include: age > 40, short surface interval, omitting decompression stops, rapid ascent, obesity, lack of sleep prior to diving, and alcohol intake within 24 hours of diving. Six of the patients had one risk factor for DCI and 15 of the patients had more than one risk factor. The patients' age was 32.6 ± 9 (19-57), number of dives 6.1 __+5.1 (1-24), greatest depth in feet 84.2 _+ 7.7 (25-200). 49% of patients received treatment within 24 hours and 51% greater than 24 hours. Patients received an average of 4.4 ± 5.1 (1-18) HBO: treatments. At hospital admission, 46% of patients reported cognitive complaints but 67% had abnormal neuropsychological testing. The cognitive impairments include: speed of processing (37%), memory (24%), attention/concentration (32%), and visuoconstruction problems (42%). Following the last HBO2 treatment, 40% of patients' test scores were within the normal range and 60% continued to exhibit cognitive impairments. The following conclusions are drawn: (a) Recreational divers with DCI are at risk for developing cognitive impairments. (b) Divers are frequently unaware of their cognitive impairments. (c) Cognitive impairments may indicate brain injury. (d) Divers should be educated, follow dive profiles and avoid known risk factors to prevent DCI and its sequelae. (e) The magnitude and duration of the residual cognitive impairments is unknown. Divers who experience symptoms of DCI while/after diving should seek prompt evaluation and treatment. We recommend that divers with DCI have neuropsychological testing to assess cognitive function. Perna, R., Durgin, D., & Geiler, S. E. Complaints of Memory Dysfunction: How Much is Related to Compromised Attention. Many individuals who have experienced a traumatic brain injury and are presenting with complaints of impaired short-term memory, actually have primary attentional impairments or problems in information processing with secondary memory impairments. If