Clinical examination for prognostication in comatose cardiac arrest patients.

OBJECTIVE: To build new algorithms for prognostication of comatose cardiac arrest patients using clinical examination, and investigate whether therapeutic hypothermia influences the value of the clinical examination. METHODS: From 2000 to 2007, 500 consecutive patients in non-traumatic coma were prospectively enrolled, 200 of whom were post-cardiac arrest. Outcome was determined by modified Rankin Scale (mRS) score at 6 months, with mRS≤3 indicating good outcome. The clinical examination was performed on days 0, 1, 3 and 7 post-arrest, and clinical variables analyzed for importance in prognostication of outcome. A classification and regression tree analysis (CART) was used to develop a predictive algorithm. RESULTS: Good outcome was achieved in 9.9% of patients. In CART analysis, motor response was often chosen as a root node, and spontaneous eye movements, pupillary reflexes, eye opening and corneal reflexes were often chosen as splitting nodes. Over 8% of patients with absent or extensor motor response on day 3 achieved a good outcome, as did 2 patients with myoclonic status epilepticus. The odds of achieving a good outcome were lower in patients who suffered asystole (OR 0.187, 95% CI: 0.039-0.875, p=0.033) compared with ventricular fibrillation or non-perfusing ventricular tachycardia, but some still achieved good outcome. The absence of pupillary and corneal reflexes on day 3 remained highly reliable for predicting poor outcome, regardless of therapeutic hypothermia utilization. CONCLUSION: The clinical examination remains central to prognostication in comatose cardiac arrest patients in the modern area. Future studies should incorporate the clinical examination along with modern technology for accurate prognostication.

Hippocampal magnetic resonance imaging abnormalities in cardiac arrest are associated with poor outcome.

BACKGROUND: The role of neuroimaging in assessing prognosis in comatose cardiac survivors appears promising, but little is known regarding the import of particular spatial patterns. We report a specific spatial imaging abnormality on magnetic resonance imaging (MRI) that portends a poor prognosis: bilateral hippocampal hyperintensities on diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) sequences. METHODS: Eighty sequential comatose cardiac arrest patients underwent MRI scans. Qualitative and quantitative regional analyses were performed. Patients were categorized as HIPPO(+) (n = 18) or HIPPO(-) (n = 62) based on whether they had bilateral hippocampal hyperintensities. Poor outcome was defined by a modified Rankin Scale (mRS) score ≥4 at 6 months. RESULTS: Patients with bilateral hippocampal abnormalities had a higher frequency of poor outcome (P = .032). HIPPO(+) patients suffered more severe cerebral injury, with lower whole brain apparent diffusion coefficient values (P = .043) and a greater number of affected regions on DWI (P = .001) and FLAIR (P = .001) than HIPPO(-) patients. The hippocampal approach was 100% specific for a poor prognosis; only 1 patient survived and remained in a vegetative state. CONCLUSIONS: Bilateral hippocampal hyperintensities on MRI may be a specific imaging finding that is indicative of poor prognosis in patients who suffer global hypoxic-ischemic injury. More research on the prognostic significance of this and similar neuroimaging patterns is indicated.

Clinical examination for outcome prediction in nontraumatic coma.

OBJECTIVES: Determine the utility of the neurologic examination in comatose patients from nontraumatic causes in the modern era. DESIGN: Prospective observational study. SETTING: Single academic medical center. PATIENTS: Data from 500 patients in nontraumatic coma collected sequentially from 2000 to 2007 in the emergency department and neuroscience, medical, and cardiac intensive care units. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical data were collected on days 0, 1, 3, and 7. Outcome was assessed at 6 months; good outcome was determined at two levels by modified Rankin Scale, ≤3 as independence and ≤4 as moderate but not severe disability. A classification and regression tree analysis was performed to determine prognostic variables, creating predictive algorithms of good vs. poor outcome for each day. Patients with coma attributable to subarachnoid hemorrhage (4/80; 5%) or global hypoxic-ischemic injury (20/202, 10%) were more likely to achieve good outcomes. The pupillary reflex was an important determinant, regardless of day or modified Rankin Scale cut point (mean odds ratio 12.51, range [6.01, 22.56] for modified Rankin Scale ≤3; mean odds ratio 19.26, range [5.38, 42.26] for modified Rankin Scale ≤4). A less robust effect was seen for oculocephalic reflexes (mean odds ratio 62.61, range [2.24, 177] for modified Rankin Scale ≤3; mean odds ratio 34.13, range [4.95, 89.93] for modified Rankin Scale ≤4). The motor response was selected as a predictor of outcome only on day 0 (odds ratio 2.35, 95% confidence interval 0.64-5.74 for modified Rankin Scale ≤3; odds ratio 2.1, 95% confidence interval 0.81-4.24 for modified Rankin Scale score ≤4). Age was not associated with outcome. CONCLUSIONS: The clinical neurologic examination remains central to determining prognosis in nontraumatic coma. Additional clinical and diagnostic variables may also aid in outcome prediction for specific disease states.

An update on brain death criteria: a simple algorithm with complex questions.

Brain death criteria have been based on 3 cardinal features throughout history: coma, brainstem areflexia, and apnea, and thus have undergone little change. In 1995, the American Academy of Neurology (AAN) detailed these criteria in a step-by-step fashion that included meeting prerequisites, performing the clinical examination, performing ancillary testing, and documentation. Fifteen years later, many questions still remain regarding the diagnosis of brain death. The Quality Standards Subcommittee of the AAN sought to answer 5 of these outstanding questions. Ultimately, their data supported the utility of the 1995 criteria and warned against the use of new technologies before proper validation. This review briefly tells the story of brain death criteria, making mention of the steps outlined by the AAN in 1995 and discussing the recent evidence released by the Quality Standards Subcommittee in the new 2010 Practice Parameter Update.

Neurologic examination and extubation outcome in the neurocritical care unit.

BACKGROUND: Extubation failure in the neurocritical care unit (NCCU) is difficult to predict, and is an important source of prolonged intensive care, exposure to morbidity, and increased cost. METHODS: In this observational cohort study in the NCCU of a tertiary care hospital, we examined patients undergoing extubation or tracheostomy with >6 h of intubation. Observational data were collected at the time of the decision to extubate or pursue tracheostomy. The primary end-point was extubation failure within 72 h. RESULTS: A total of 378 tracheostomy versus extubation decisions were made on 339 individuals, resulting in 93 tracheostomies and 285 extubations. The extubation failure rate was 48/285 (16.8%). Individuals who underwent extubation had similar GCS scores [median 10T (IQR 10-11), P = 0.21]. Extubation failures had similar rates of pneumonia and fever, chest X-ray (CXR) findings, and admission diagnoses (P = NS). Factors associated with success in univariate analysis included intact gag reflex, normal eye movements, ability to close eyes to command, and ability to cough to command (all P < 0.05). In multivariate analysis, the ability to follow four commands (close eyes, show two fingers, wiggle toes, cough to command) was associated with success (P = 0.01). ROC analysis identified a significant difference in favor of a multivariate model incorporating four commands over GCS alone (P = 0.007). CONCLUSION: The ability to follow four commands and other examination criteria were strongly associated with extubation success in this observational study. Modeling suggests that specific neurologic examination parameters provide additional predictive information over GCS alone. A prospective, protocol-driven trial is needed to test and expand these findings.

Enhancement's place in medicine.

Many enhancement technologies are distributed by healthcare professionals-by physicians-who are held to the Hippocratic Oath and the goals of medicine. While the ethics of enhancement has been widely discussed with regard to the social justice, humanism, morals and normative values of these interventions, their place in medicine has not attracted a great deal of attention. This paper investigates the potential for enhancement technologies to fulfil the goals of medicine, arguing that they play a role in promoting the health of individuals, and thus, an unavoidable place in medicine. It also warns of potential dangers, suggesting a set of guidelines to initiate conversations regarding the role and responsibilities of physicians practising in an era of enhancement.