Limitation of life support after resuscitation from cardiac arrest: practice in Belgium and Austria

Ability of neuron-specific enolase to predict survival to hospital discharge after successful cardiopulmonary resuscitation

Background:

Accurate prediction of survival to hospital discharge in patients who achieve return of spontaneous circulation after cardiopulmonary resuscitation (CPR) has significant ethical and socioeconomic implications. We investigated the prognostic performance of serum neuron-specific enolase (NSE), a biochemical marker of ischemic brain injury, after successful CPR.

Methods:

In-hospital or out-of-hospital patients with nontraumatic normothermic cardiac arrest who achieved return of spontaneous circulation (ROSC) following at least 5 minutes of CPR were eligible. Neuron-specific enolase levels were assessed immediately, 6 hours, 12 hours and 2 days after ROSC. Subjects were followed to death or hospital discharge.

Results:

Seventeen patients (7 men, 10 women) were enrolled during a 1-year period. Median (range) NSE levels in survivors and non-survivors respectively were as follows: immediately after ROSC: 14.0 μg/L (9.1–51.4 μg/L) versus 25.9 μg/L (10.2–57.5 μg/L); 6 hours after ROSC: 15.2 μg/L (9.7–30.8 μg/L) versus 25.6 μg/L (12.7–38.2 μg/L); 12 hours after ROSC: 14.0 μg/L (8.6–32.4 μg/L) versus 28.5 μg/L (11.0–50.7 μg/L); and 48 hours after ROSC: 13.1 μg/L (7.8–29.5 μg/L) versus 52.0 μg/L (29.1–254.0 μg/L). Non-survivors had significantly higher NSE levels 48 hours after ROSC than surivors (p = 0.04) and showed a trend toward higher values during the entire time course following ROSC. An NSE concentration of >30 μg/L 48 hours after ROSC predicted death with a high specificity (100%: 95% confidence interval [CI] 85%–100%), and a level of 29 μg/L or less at 48 hours predicted survival with a high specificity (100%: 95% CI 83%–100%).

Conclusions:

Serum NSE levels may have clinical utility for the prediction of survival to hospital discharge in patients after ROSC following CPR over 5 minutes in duration. This study is small, and our results are limited by wide confidence intervals. Further research on ability of NSE to facilitate prediction and clinical decision-making after cardiac arrest is warranted.

Predictors of early care withdrawal following out-of-hospital cardiac arrest

AIMS

To identify factors that associated with early care withdrawal in out-of-hospital cardiac arrest patients.

METHODS

Data was collected from 189 survivors to hospital admission. Patients were classified by survival status upon hospital discharge, and those who died were categorized into withdrawal vs. no withdrawal of care. Those who had care withdrawn were further subdivided into early care withdrawal i.e. ≤72 h vs. late withdrawal >72 h. Multivariable adjusted odds ratios were used to assess factors associated with early care withdrawal.

RESULTS

Of 189 patients with cardiac arrest, only 36 had advanced directives (19%) and 99 (52%) had care withdrawn. Most patients whose care was withdrawn died in hospital (94/99, 95%), and the remainder died in hospice. Care was withdrawn early ≤72 h in the majority of patients (59/94, 63%). Median time to early care withdrawal was 2 days IQR (1-3). Factors associated with early care withdrawal were age ≥75 years, poor initial neurologic exam, multiple co morbidities, multi-organ failure, lactic acid ≥10 mmolL(-1), Caucasian race and absence of bystander CPR. Advance directives did not appear to determine early care withdrawal.

CONCLUSIONS

Although most cardiac arrest patients do not have advance directives, care is often withdrawn in more than 50% and in many before the accepted time for neurological awakening (72h). The decision to withdraw care is influenced by older age, race, preexisting co morbidities, multi-organ failure, and a poor initial neurological exam. Further studies are needed to better understand this phenomenon and other sociological factors that guide such decisions.

Post-resuscitation care at the emergency department with critical care facilities--a length-of-stay analysis

AIM OF THE STUDY

An emergency department providing critical care will have an effect on outcome and intensive-care-units' resources by avoiding unnecessary or futile intensive-care admissions and thereby save hospital expenses. The study focussed on this result.

METHODS

The study employed a retrospective analysis of prospectively collected data of out-of-hospital cardiac arrest patients with return of spontaneous circulation, comatose on arrival. Outcomes and length of stay of patients who either stayed at the 'emergency department only' or were 'transferred in addition to an intensive care unit' were compared. Linear regression with log length of stay as outcome and 'emergency department only' as predictor with covariates was used for modelling.

RESULTS

From 1991 to 2008, out of 1236 patients (age 57 ± 15 years, female 31%), the 'emergency department only' group (n=349 (28%)) survived to discharge in 81(23%) cases, with a median length-of-stay in critical care of 1.7 (interquartile range 0.8; 3.1) days. The patients 'transferred in addition to an intensive care unit' (n=887 (72%)), with a survival rate of 55% (n=486, p<0.001) stayed 10 (5; 18) days (p<0.001). The length-of-stay in hospital was significantly shorter if patients were treated in the 'emergency department only' independent of other cardiac-arrest-related factors (regression coefficient -1.42, confidence interval -1.60 to -1.24).

CONCLUSIONS

An emergency department with critical care prevents admissions to intensive care units in 28% of patients with out-of-hospital cardiac arrest. It saves intensive-care-unit resources and shortens length of stay for comatose out-of-hospital cardiac-arrest survivors, regardless of their outcome.

Biochemical markers (NSE, S-100, IL-8) as predictors of neurological outcome in patients after cardiac arrest and return of spontaneous circulation

Predicting the neurological outcome after resuscitation and a return of spontaneous circulation of resuscitated patients still remains a difficult issue. Over the past decade numerous studies have been elaborated to provide the physician with tools to assess as early as possible the neurological outcome of patients with cardiac arrest and return of spontaneous circulation and to decide about further therapeutic management. We summarise the most important ones, giving special focus to three biochemical markers (neuron specific enolase, a protein soluble in 100% ammonium sulfate and interleukin-8), which, when combined with standard neuro-functional and imaging techniques, can serve as potent predictors of neurological outcome in these patients. Despite current limitations about the prognostic significance of these markers - their inferior sensitivity, the different cut-off levels used by several investigators and their variable unequal rise over time - they can give useful information about short and long-term neurological outcome. A comprehensive set of clinical, electrophysiological, biochemical and imaging measures, obtained in a uniform manner in a cohort of patients without limitations in care, could provide a more objective set of comprehensive prognostic indicators.

Brain arrest neurological outcome scale (BrANOS): predicting mortality and severe disability following cardiac arrest

BACKGROUND

To create a predictive scale of neurological outcome following cardiac arrest (CA) that incorporates radiological and clinical markers of brain injury.

METHODS AND RESULTS

Brain arrest neurologic outcome scale (BrANOS) is a prospective 16-point scale. It consisted of three variables: (1) duration of arrest (DAR), (2) reversed Glasgow coma scale (GCS), and (3) Hounsfield unit (HU) ratio on non-contrast CT scan of the head. Reversed GCS score was defined as 15-GCS (best GCS in the first 24 h). HU ratio was defined as the density ratio of the caudate nucleus over the posterior limb of the internal capsule measured on unenhanced CT scan of the brain. We identified 32 comatose patients who had: (1) CT scan performed within 48 h of event; (2) no previous history of either coma, severe head trauma, cardiac arrest or stroke. Primary outcome was defined as alive or dead. Secondary outcome was the Glasgow outcome score recorded on discharge. Patient demographics were collated from retrospective chart review. Patients' mean age was 63 +/- 3 years (mean +/- S.E.M.); 44% were females. Mortality rate was 81%. Mean DAR was 21 +/- 2 min. Survivors had a significantly lower BrANOS score (8 +/- 2 points) compared to non-survivors (13 +/- 1) (P = 0.006). BrANOS was a strong predictor of mortality alone (ROC = 0.86) and mortality with severe disability combined (ROC = 0.9). The scale had a 100% specificity and positive predictive value.

CONCLUSIONS

BrANOS is a reliable predictor of neurological outcome following CA. It is the first scale to incorporate clinical and radiological markers of brain injury.

Time course of serum neuron-specific enolase. A predictor of neurological outcome in patients resuscitated from cardiac arrest

BACKGROUND AND PURPOSE

The prediction of neurological outcome in comatose cardiac arrest survivors has enormous ethical and socioeconomic implications. The purpose of the present study was to investigate the prognostic relevance of the time course of serum neuron-specific enolase (NSE) as a biochemical marker of hypoxic brain damage.

METHODS

Serial analysis of serum NSE levels was performed in 56 patients resuscitated from witnessed, nontraumatic, normothermic, in- or out-of-hospital cardiac arrest. The neurological outcome was evaluated with the use of the cerebral performance category (CPC) within 6 months after restoration of spontaneous circulation (ROSC). The Mann-Whitney U test was used to compare patients with good (CPC 1 to 2) and bad (CPC 3 to 4) neurological outcome. The diagnostic performance at different time points after ROSC was described in terms of areas under receiver operating characteristic curves according to standard methods.

RESULTS

Patients with a bad neurological outcome (CPC 3 to 4) had significantly higher NSE levels than those with a good neurological outcome at 12 (P=0.004), 24 (P=0.04), 48 (P<0.001), and 72 hours (P<0.001) after ROSC. The maximum NSE level measured within 72 hours after ROSC was also significantly higher in patients with a bad neurological outcome (P<0.001). The NSE value at 72 hours after ROSC was the best predictor of neurological outcome (area under the curve=0.92+/-0.04). In addition, we also found a significant difference in the time course of NSE concentrations during the first 3 days after ROSC.

CONCLUSIONS

Serum NSE levels are valuable adjunctive parameters for assessing neurological outcome after cardiac arrest.