Feasibility of cognitive functional assessment in cardiac arrest survivors using an abbreviated laptop-based neurocognitive battery.

Cardiac arrest survivors exhibit varying degrees of neurological recovery even in the setting of targeted temperature management (TTM) use, ranging from severe impairments to making a seemingly full return to neurologic baseline function. We sought to explore the feasibility of utilizing a laptop-based neurocognitive battery to identify more subtle cognitive deficits in this population. In a convenience sample of cardiac arrest survivors discharged with a cerebral performance category (CPC) of 1, we evaluated the use of a computerized neurocognitive battery (CNB) in this group compared to a healthy control normative population. The CNB was designed to test 11 specific neurocognitive domains, including such areas as working memory and spatial processing. Testing was scored for both accuracy and speed. In a feasibility convenience sample of 29 cardiac arrest survivors, the mean age was 52.9±16.7 years; 12 patients received postarrest TTM and 17 did not receive TTM. Patients tolerated the battery well and performed at normative levels for both accuracy and speed on most of the 11 domains, but showed reduced accuracy of working memory and speed of spatial memory with large magnitudes (>1 SD), even among those receiving TTM. Across all domains, including those using speed and accuracy, 7 of the 29 subjects (24%) achieved statistically significant scores lower from the normative population in two or more domains. In this population of CPC 1 cardiac arrest survivors, a sensitive neurocognitive battery was feasible and suggests that specific cognitive deficits can be detected compared to a normative population, despite CPC 1 designation. Such testing might allow improved measurement of outcomes following TTM interventions in future trials.

Pyrexia and neurologic outcomes after therapeutic hypothermia for cardiac arrest.

OBJECTIVE: Therapeutic hypothermia, also known as targeted temperature management (TTM), improves clinical outcomes in patients resuscitated from cardiac arrest. Hyperthermia after discontinuation of active temperature management ("rebound pyrexia") has been observed, but its incidence and association with clinical outcomes is poorly described. We hypothesized that rebound pyrexia is common after rewarming in post-arrest patients and is associated with poor neurologic outcomes. METHODS: Retrospective multicenter US clinical registry study of post-cardiac arrest patients treated with TTM at 11 hospitals between 5/2005 and 10/2011. We assessed the incidence of rebound pyrexia (defined as temperature >38°C) in post-arrest patients treated with TTM and subsequent clinical outcomes of survival to discharge and "good" neurologic outcome at discharge, defined as cerebral performance category (CPC) 1-2. RESULTS: In this cohort of 236 post-arrest patients treated with TTM, mean age was 58.1 ± 15.7 y and 106/236 (45%) were female. Of patients who survived at least 24h after TTM discontinuation (n=167), post-rewarming pyrexia occurred in 69/167 (41%), with a median maximum temperature of 38.7 (IQR 38.3-38.9). There were no significant differences between patients experiencing any pyrexia and those without pyrexia regarding either survival to discharge (37/69 (54%) v 51/98 (52%), p=0.88) or good neurologic outcomes (26/37 (70%) v 42/51 (82%), p=0.21). We compared patients with marked pyrexia (greater than the median pyrexia of 38.7°C) versus those who experienced no pyrexia or milder pyrexia (below the median) and found that survival to discharge was not statistically significant (40% v 56% p=0.16). However, marked pyrexia was associated with a significantly lower proportion of CPC 1-2 survivors (58% v 80% p=0.04). CONCLUSIONS: Rebound pyrexia occurred in 41% of TTM-treated post-arrest patients, and was not associated with lower survival to discharge or worsened neurologic outcomes. However, among patients with pyrexia, higher maximum temperature (>38.7°C) was associated with worse neurologic outcomes among survivors to hospital discharge.