Bispectral index (BIS) and suppression ratio (SR) as an early predictor of unfavourable neurological outcome after cardiac arrest

Introduction

Predicting the neurological outcome after cardiopulmonary resuscitation (CPR) is extremely difficult. We tested the hypothesis whether monitoring of bispectral index (BIS) and suppression ratio (SR) could serve as an early prognostic indicator of neurological outcomes after CPR.

Methods

Cerebral monitoring (BIS, SR) was started as soon as possible after initiation of CPR and was continued for up to 72 h. The functional neurological outcome was measured on day 3, day 7 and again one month after CPR via a clinical examination and assessment according to the cerebral performance category score (CPC).

Results

In total 79 patients were included. Of these, 26 patients (32.9%) survived the observation period of one month; 7 of them (8.9%) showed an unfavourable neurological outcome. These 7 patients had significantly lower median BIS values (25 [21;37] vs. 61 [51;70]) and higher SR (56 [44;64] vs. 7 [1;22]) during the first 4 h after the initiation of CPR. Using BIS < 40 as threshold criteria, unfavourable neurological outcome was predicted with a specificity of 89.5% and a sensitivity of 85.7%. The odds ratio for predicting an unfavourable neurological outcome was 0.921 (95% CI 0.853–0.985). The likelihood to remain in a poor neurological condition decreased by 7.9% for each additional point of BIS, on average.

Conclusion

Our results suggest that BIS and SR are helpful tools in the evaluation of the neurological outcomes of resuscitated patients. Nevertheless, therapeutic decisions have to be confirmed through further examinations due to the far-ranging consequences of false positive results.     

Feasibility of bispectral index monitoring to guide early post-resuscitation cardiac arrest triage

Introduction

Triage after resuscitation from cardiac arrest is hindered by reliable early estimation of brain injury. We evaluated the performance of a triage model based on early bispectral index (BIS) findings and cardiac risk classes.

Methods

Retrospective evaluation of serial patients resuscitated from cardiac arrest, unable to follow commands, and undergoing hypothermia. Patients were assigned to a cardiac risk group: STEMI, VT/VF shock, VT/VF no shock, or PEA/asystole, and to a neurological dysfunction group, based on the BIS score following first neuromuscular blockade (BISi), and classified as BISi > 20, BISi 10–20, or BISi < 10. Cause of death was described as neurological or circulatory.

Results

BISi in 171 patients was measured at 267(±177) min after resuscitation and 35(±1.7)°C. BISi < 10 suffered 82% neurological-cause and 91% overall mortality, BISi 10–20 35% neurological and 55% overall mortality, and BISi > 20 12% neurological and 36% overall mortality. 33 patients presented with STEMI, 15 VT/VF-shock, 41 VT/VF-no shock, and 80 PEA/asystole. Among BISi > 20 patients, 75% with STEMI underwent urgent cardiac catheterization (cath) and 94% had good outcome. When BISi > 20 with VT/VF and shock, urgent cath was infrequent (33%), and 4 deaths (44%) were uniformly of circulatory etiology. Of 56 VT/VF patients without STEMI, 24 were BISi > 20 but did not undergo urgent cath – 5(20.8%) of these had circulatory-etiology death. Circulatory-etiology death also occurred in 26.5% BIS > 20 patients with PEA/asystole. When BISi < 10, a neurological etiology death dominated independent of cardiac risk group.

Conclusions

Neurocardiac triage based on very early processed EEG (BIS) is feasible, and may identify patients appropriate for individualized post-resuscitation care. This and other triage models warrant further study.     

Regional cerebral oxygen saturation after cardiac arrest in 60 patients—A prospective outcome study

Introduction

Non-invasive near-infrared spectroscopy (NIRS) offers the possibility to determine regional cerebral oxygen saturation (rSO₂) in patients with cardiac arrest. Limited data from recent studies indicate a potential for early prediction of neurological outcome.

Methods

Sixty cardiac arrest patients were prospectively enrolled, 22 in-hospital cardiac arrest (IHCA) and 38 out-of-hospital cardiac arrest (OHCA) patients respectively. NIRS of frontal brain was started after return of spontaneous circulation (ROSC) during admission to ICU and was continued until normothermia. Outcome was determined at ICU discharge by the Pittsburgh Cerebral Performance Category (CPC) and 6 months after cardiac arrest.

Results

A good outcome (CPC 1–2) was achieved in 23 (38%) patients, while 37 (62%) had a poor outcome (CPC 3–5). Patients with good outcome had significantly higher rSO₂ levels (CPC 1–2: rSO₂ 68%; CPC 3–5: rSO₂ 58%; p < 0.01). For good and poor outcome median rSO₂ within the first 24 h period was 66% and 59% respectively and for the following 16 h period 68% and 59% (p < 0.01). Outcome prediction by area of rSO₂ below a critical threshold of rsO₂ = 50% within the first 40 h yielded 70% specificity and 86% sensitivity for poor outcome.

Conclusion

On average, rSO₂ within the first 40 h after ROSC is significantly lower in patients with poor outcome, but rSO₂ ranges largely overlap between outcome groups. Our data indicate limited potential for prediction of poor outcome by frontal brain rSO₂ measurements.     

The prognostic value of continuous amplitude-integrated electroencephalogram applied immediately after return of spontaneous circulation in therapeutic hypothermia-treated cardiac arrest patients

Introduction

The purpose of this study was to examine the prognostic value of continuous amplitude-integrated electroencephalogram (aEEG) applied immediately after return of spontaneous circulation (ROSC) in therapeutic hypothermia (TH)-treated cardiac arrest patients.

Methods

From September 2010 to August 2011, we prospectively studied comatose patients treated with TH after cardiac arrest who were monitored with aEEG. Monitoring at the forehead was applied as soon as possible after ROSC in the emergency department and continued until recovery of consciousness, death, or 72 h after ROSC. Neurological outcome was assessed with the Cerebral Performance Category (CPC) scale at hospital discharge, and good neurological outcome was defined as a CPC score of 1 or 2.

Results

A total of 55 TH-treated patients were included. Monitoring started at a median of 96 min after ROSC (interquartile range, 49–174). At discharge, 28 patients had a CPC of 1–2, and 27 patients had a CPC of 3–5. Seventeen patients had a continuous normal voltage (CNV) trace at the start of monitoring, and this voltage was strongly associated with a good outcome (16/17 [94.1%]; sensitivity and specificity of 57.1 and 96.3%, respectively). No development of a CNV trace within the recorded period accurately predicted a poor outcome (21/21 [100%]; sensitivity and specificity of 77.8 and 100%, respectively).

Conclusions

An initial CNV trace in aEEG applied to forehead immediately after ROSC is a good early predictor of a good outcome in TH-treated cardiac arrest patients. Conversely, no development of a CNV trace within 72 h is an accurate and reliable predictor of a poor outcome with a false-positive rate of 0%.     

The Glasgow coma score is a predictor of good outcome in cardiac arrest patients treated with therapeutic hypothermia

Background

With the recent introduction of therapeutic hypothermia the application of sedation becomes necessary in cardiac arrest patients. We therefore analysed the usefulness of the Glasgow coma score (GCS) for outcome prediction in survivors of cardiac arrest treated with therapeutic hypothermia.

Patients and methods

In a prospective observational study we identified 72 comatose patients admitted to our intensive care unit after cardiac arrest. All patients were treated with therapeutic hypothermia. After sedation stop the Glasgow coma scale (GCS) was recorded until day 4. Neurological outcome was assessed using the Pittsburgh cerebral performance category (CPC) score.

Results

Forty-four of 72 patients (61%) were discharged with a favourable neurological outcome (CPC 1 + 2). GCS was significantly higher in patients with good outcome compared to patients with unfavourable outcome at every point in time after sedation stop (p < 0.001). The value for prediction of good outcome with the highest accuracy was a GCS > 4 at the first day after sedation stop (sensitivity 61%, PPV 90% and AUC 0.808) and GCS > 6 in the following days (sensitivity 84%, PPV 92.5% and AUC 0.921 at day 4). In particular a score of >3 on the motor component of the GCS predicted good outcome with a specificity of 100% (sensitivity 43%) at the first day.

Conclusions

Our results indicate that monitoring of the GCS is a simple and reliable method for clinical outcome assessment in patients treated with therapeutic hypothermia. Thus, GCS monitoring remains a powerful tool to predict outcome of patients treated with therapeutic hypothermia.     

Tau proteins in serum predict neurological outcome after hypoxic brain injury from cardiac arrest: Results of a pilot study

Objective

To conduct a pilot study to evaluate the prognostic potential of serum tau protein measurements to predict neurological outcome 6 months following resuscitation from cardiac arrest.

Methods

In this retrospective observational study, we employed a new ultra sensitive digital immunoassay technology to examine serial serum samples from 25 cardiac arrest patients to examine tau release into serum as a result of brain hypoxia, and probe for its significance predicting six-month neurological outcome. Serial blood samples were obtained from resuscitated cardiac arrest survivors during their first five days in an intensive care unit, and serum total tau was measured. Cerebral function assessments were made using Cerebral Performance Categorization (CPC) at discharge from the ICU and six months later. Tau data were analyzed in the context of 6-month CPC scores.

Results

Tau elevations ranged from modest (<10 pg/mL) to very high (hundreds of pg/mL), and exhibited unexpected bi-modal kinetics in some patients. Early tau elevations appeared within 24 h of cardiac arrest, and delayed elevations appeared after 24–48 h. In patients with delayed elevations, areas under the curves of tau concentration vs. hours since cardiac arrest were highly predictive of 6-month outcome (P < 0.0005).

Conclusion

High-sensitivity serum tau measurements combined with an understanding of tau release kinetics could have utility for hypoxic brain injury assessment and prediction of cerebral function outcome.     

Neurologic prognostication and bispectral index monitoring after resuscitation from cardiac arrest

Objective

While the use of therapeutic hypothermia (TH) has improved outcomes after resuscitation from cardiac arrest, prognostication of survival and neurologic function remains difficult during the post-arrest time period. Bispectral index (BIS) monitoring, a non-invasive measurement of simplified electroencephalographic data, is increasingly being considered for post-arrest neurologic assessment and outcomes prediction, although data supporting the technique are limited. We hypothesized that BIS values within 24 h after resuscitation would correlate with neurologic outcomes at discharge.

Methods

We prospectively collected BIS data in consecutive patients initially resuscitated from cardiac arrest and treated with TH in one academic medical center. We assessed BIS values in context of cerebral performance category (CPC) assessment on the day of discharge.

Results

Data were collected in 62 post-arrest patients, of whom 26/62 (42%) survived to hospital discharge. Mean BIS values at 24 h post-resuscitation were significantly different in the survivors with CPC 1-2 (“good” outcome) vs those with CPC 3-5 (“poor” outcome) or death during hospitalization (49 ± 13 vs 30 ± 20; p < 0.001). Receiver operator characteristic analysis suggested that 24 h BIS was most predictive of CPC 1-2 outcome compared to the other timepoints; a BIS cutpoint of 45 exhibited a sensitivity of 63% and a specificity of 86%, with a positive likelihood ratio of 4.67. Sixteen patients exhibited a BIS of zero during at least one timepoint; all of these patients died during hospitalization.

Conclusions

BIS monitoring values at 24 h post-resuscitation are correlated with neurologic outcomes in patients undergoing TH treatment. In 16/62 patients, a BIS of zero at any timepoint was observed, which was uniformly correlated with poor outcome after resuscitation from cardiac arrest; however, a non-zero BIS is insufficient as a sole predictor of good neurologic survival.     

Predictors of long-term survival after out-of-hospital cardiac arrest: The impact of Activities of Daily Living and Cerebral Performance Category scores

Background

Current focus on immediate survival from out-of-hospital cardiac arrest (OHCA) has diverted attention away from the variables potentially affecting long-term survival.

Aim

To determine the relationship between neurological and functional status at hospital discharge and long-term survival after OHCA.

Methods

Prospective data collection for all OHCA patients aged >18 years in the Jerusalem district (n = 1043, 2008–2009). Primary outcome measure: Length of survival after OHCA. Potential predictors: Activities of Daily Living (ADL) and Cerebral Performance Category (CPC) scores at hospital discharge, age and sex.

Results

There were 52/279 (18.6%) survivors to hospital discharge. Fourteen were discharged on mechanical ventilation (27%). Interviews with survivors and/or their legal guardians were sought 2.8 ± 0.6 years post-arrest. Eighteen died before long-term follow-up (median survival 126 days, IQR 94–740). Six improved their ADL and CPC scores between discharge and follow-up. Long-term survival was positively related with lower CPC scores (p = 0.002) and less deterioration in ADL from before the arrest to hospital discharge (p = 0.001). For each point increment in ADL at hospital discharge, the hazard ratio of death was 1.31 (95%CI 1.12, 1.53, p = 0.001); this remained unchanged after adjustment for age and sex (HR 1.26, 95%CI 0.07, 1.48, p = 0.005).

Conclusions

One-third of the patients discharged from hospital after OHCA died within 30 months of the event. Long-term survival was associated both with better neurological and functional level at hospital discharge and a smaller decrease in functional limitation from before to after the arrest, yet some patients with a poor neurological outcome survived prolonged periods after hospital discharge.     

The effect of percutaneous coronary intervention in patients suffering from ST-segment elevation myocardial infarction complicated by out-of-hospital cardiac arrest on 30 days survival

Aim of the study

To question the beneficial effects of the recommended early percutaneous coronary intervention (PCI) after out-of-hospital cardiac arrest on 30-day survival with favourable neurological outcome.

Methods

Prospectively collected data of 1277 out of hospital cardiac arrest patients between 2005 and 2010 from a registry at a tertiary care university hospital were used for a cohort study.

Results

In 494 (39%) arrest patients ST-segment elevation was identified in 249 (19%). Within 12 h after restoration of spontaneous circulation catheter laboratory investigations were initiated in 197 (79%) and PCI in 183 (93%) (78% got PCI in less than180 min). Adjustment for a cumulative time without chest compressions <2 min, initial shockable rhythm, cardiac arrest witnessed by healthcare professionals, and a higher core temperature at time of hospitalization reduced the effect of PCI on favourable neurological outcome at 30 days (OR 1.40; 95% CI, 0.53–3.7) compared to the univariate analysis (OR 2.52; 95% CI, 1.42–4.48).

Conclusion

This cohort study failed to demonstrate the beneficial effects of PCI as part of post-resuscitation care on 30-day survival with a favourable neurological outcome.     

The occurrence of shivering in cardiac arrest survivors undergoing therapeutic hypothermia is associated with a good neurologic outcome

Background

The incidence of shivering in cardiac arrest survivors who undergo therapeutic hypothermia (TH) is varied. Its occurrence is dependent on the integrity of multiple peripheral and central neurologic pathways. We hypothesized that cardiac arrest survivors who develop shivering while undergoing TH are more likely to have intact central neurologic pathways and thus have better neurologic outcome as compared to those who do not develop shivering during TH.

Methods

Prospectively collected data on consecutive adult patients admitted to a tertiary center from 1/1/2007 to 11/1/2010 that survived a cardiac arrest and underwent TH were retrospectively analyzed. Patients who developed shivering during the cooling phase of TH formed the “shivering” group and those that did not formed the “non-shivering” group. The primary end-point: Pittsburgh Cerebral Performance Category (CPC) scale; good (CPC 1–2) or poor (CPC 3–5) neurological outcome prior to discharge from hospital.

Results

Of the 129 cardiac arrest survivors who underwent TH, 34/94 (36%) patients in the “non-shivering” group as compared to 21/35 (60%) patients in the “shivering” group had good neurologic outcome (P = 0.02). After adjusting for confounders using binary logistic regression, occurrence of shivering (OR: 2.71, 95% CI 1.099–7.41, P = 0.04), time to return of spontaneous circulation (OR: 0.96, 95% CI 0.93–0.98, P = 0.004) and initial presenting rhythm (OR: 4.0, 95% CI 1.63–10.0, P = 0.002) were independent predictors of neurologic outcome.

Conclusion

The occurrence of shivering in cardiac arrest survivors who undergo TH is associated with an increased likelihood of good neurologic outcome as compared to its absence.     

Neuron specific enolase and S-100B as predictors of outcome after cardiac arrest and induced hypothermia

Aim

To assess the prognostic value of repetitive serum samples of neuron specific enolase (NSE) and S-100B in cardiac arrest patients treated with hypothermia.

Methods

In a three-centre study, comatose patients after cardiac arrest were treated with hypothermia at 33 °C for 24 h, regardless of cause or the initial rhythm. Serum samples were collected at 2, 24, 48 and 72 h after the arrest and analysed for NSE and S-100B in a non-blinded way. The cerebral performance categories scale (CPC) was used as the outcome measure; a best CPC of 1–2 during 6 months was regarded as a good outcome, a best CPC of 3–5 a poor outcome.

Results

One centre was omitted in the NSE analysis due to missing 24 and 48 h samples. Two partially overlapping groups were studied, the NSE group (n = 102) and the S-100B group (n = 107). NSE at 48 h >28 μg/l (specificity 100%, sensitivity 67%) and S-100B >0.51 μg/l at 24 h (specificity 96%, sensitivity 62%) correlated with a poor outcome, and so did a rise in NSE of >2 μg/l between 24 and 48 h (odds ratio 9.8, CI 3.5–27.7). A majority of missing samples (n = 123) were from the 2 h sampling time (n = 56) due to referral from other hospitals or inter-hospital transfer.

Conclusion

NSE was a better marker than S-100B for predicting outcome after cardiac arrest and induced hypothermia. NSE above 28 μg/l at 48 h and a rise in NSE of more than 2 μg/l between 24 and 48 h were markers for a poor outcome.     

Bispectral index monitoring is useless during cardiac arrest patients’ resuscitation

Aim

It has been suggested that out-of-hospital bispectral (BIS) index monitoring during advanced cardiac life support (ACLS) might provide an indication of cerebral resuscitation. The aims of our study were to establish whether BIS values during ACLS might predict return to spontaneous circulation, and whether BIS values on hospital admission might predict survival.

Materials and methods

This was a prospective observational study in 92 patients with cardiac arrest who received basic life support from a fire-fighter squad and ACLS on arrival of an emergency medical team on the scene. BIS values, electromyographic activity, and signal quality index were recorded throughout resuscitation and out-of-hospital management.

Results

Seven patients had recovered spontaneous cardiac activity by the time the medical team arrived on scene. Of the 92 patients, 62 patients died on scene and 30 patients returned to spontaneous cardiac activity and were admitted to hospital. The correlation between BIS values and end-tidal CO₂ during the first minutes of ACLS was poor (r² = 0.02, P = 0.19). Of the 30 admitted patients, 27 died. Three were discharged with no disabilities. There was no significant difference in BIS values on admission between the group of patients who died and the group who survived (P = 0.78).

Conclusions

Although BIS monitoring during resuscitation was not difficult, it did not predict return to spontaneous cardiac activity, nor survival after admission to intensive care. Its use to monitor cerebral function during ACLS is therefore pointless.     

The influence of induced hypothermia and delayed prognostication on the mode of death after cardiac arrest

Background

Brain injury is considered the main cause of death in patients who are hospitalized after cardiac arrest (CA). Induced hypothermia is recommended as neuroprotective treatment after (CA) but may affect prognostic parameters. We evaluated the effect of delayed neurological prognostication on the mode of death in hypothermia-treated CA-survivors.

Study design

Retrospective study at a Swedish university hospital, analyzing all in-hospital and out-of-hospital CA-patients treated with hypothermia during a 5-year period. Cause of death was categorized as brain injury, cardiac disorder or other. Multimodal neurological prognostication and decision on level of care was performed in comatose patients 72 h after rewarming. Neurological function was evaluated by Cerebral Performance Categories scale (CPC).

Results

Among 162 patients, 76 survived to hospital discharge, 65 of whom had a good neurological outcome (CPC 1–2), and 11 were severely disabled (CPC 3). No patient was in vegetative state. The cause of death was classified as brain injury in 61 patients, cardiac disorder in 14 and other in 11. Four patients were declared brain dead and became organ donors. They were significantly younger (median 40 years) and with long time to ROSC. Active intensive care was withdrawn in 50 patients based on a statement of poor neurological prognosis at least 72 h after rewarming. These patients died, mainly from respiratory complications, at a median 7 days after CA.

Conclusion

Following induced hypothermia and delayed neurological prognostication, brain injury remains the main cause of death after CA. Most patients with a poor prognosis statement died within 2 weeks.     

C-reactive protein levels after cardiac arrest in patients treated with therapeutic hypothermia

Aim

Prognostication of outcome after cardiac arrest (CA) is challenging. We assessed the prognostic value of daily blood levels of C-reactive protein (CRP), a cheap and widely available inflammatory biomarker, after CA.

Methods

We reviewed the data of all patients admitted to our intensive care unit (ICU) after CA between January 2009 and December 2011 and who survived for at least 24 h. We collected demographic data, CA characteristics (initial rhythm; location of arrest; time to return of spontaneous circulation [ROSC]), occurrence of infection, ICU survival and neurological outcome at three months (good = cerebral performance category [CPC] 1–2; poor = CPC 3–5). CRP levels were measured daily from admission to day 3.

Results

A total of 130 patients were admitted after successful resuscitation from CA and survived more than 24 h; 76 patients (58%) developed an infection and overall mortality was 56%. CRP levels increased from admission to day 3. CRP levels were higher in in-hospital than in out-of-hospital CA, especially on admission and day 1 (44.1 vs. 2.1 mg L⁻¹ and 74.5 vs. 29.5 mg L⁻¹, respectively; p < 0.001), and in patients with non-shockable than in those with shockable rhythms. In a logistic regression model, high CRP levels on admission were independently associated with poor neurological outcome at 3 months.

Conclusion

CRP levels increase in the days following successful resuscitation of CA. Higher CRP levels in patients with in-hospital CA, non-shockable rhythms and infection, suggest a greater inflammatory response in these patients. High CRP levels on admission may identify patients at high-risk of poor outcome and could be a target for future therapies.     

Cardiac arrest due to accidental hypothermia—A 20 year review of a rare condition in an urban area

Background

Accidental hypothermic cardiac arrest is associated with unfortunate prognosis and large studies are rare. We therefore have performed an outcome analysis in patients that were admitted to Vienna University Hospital with the diagnosis of accidental hypothermic cardiac arrest.

Methods

This study employed a retrospective outcome analysis of prospectively collected data in a selected cohort of hypothermic cardiac arrest patients. We screened 3800 cardiac arrest patients, treated at our department between 1991 and 2010, for eligibility. Inclusion criteria were cardiac arrest with a body core temperature ≤28 °C and return of spontaneous circulation.

Results

A total of 18 patients who achieved return of spontaneous circulation were analysed. Nine patients (50%) achieved survival in good neurologic condition (defined as cerebral performance category CPC 1 or 2). Accidental hypothermia with consecutive cardiac arrest was caused by intoxication in most cases (67%). These patients had a better outcome than patients with other causes of accidental hypothermic cardiac arrest (OR = 28; 95%KI 2–37.9; p < 0.01). Hypothermia associated typical ECG changes after return of spontaneous circulation (Osborne waves) were more frequent in the surviving population (OR 16; 95%KI 1.3–19.5; p = 0.05).

Conclusions

Accidental hypothermic cardiac arrest in a central European urban area is rare. Prognosis was excellent in patients where hypothermic cardiac arrest was caused by intoxication.     

The impact of severe acidemia on neurologic outcome of cardiac arrest survivors undergoing therapeutic hypothermia

Introduction

Therapeutic Hypothermia (TH) has become a standard of care in improving neurological outcomes in cardiac arrest (CA) survivors. Previous studies have defined severe acidemia as plasma pH < 7.20. We investigated the influence of severe acidemia at the time of initiation of TH on neurological outcome in CA survivors.

Methods

A retrospective analysis was performed on 196 consecutive CA survivors (out-of-hospital CA and in-hospital CA) who underwent TH with endovascular cooling between January 2007 and October 2012. Arterial blood gas drawn prior to initiation of TH was utilized to measure pH in all patients. Shockable and non-shockable CA patients were divided into two sub-groups based on pH (pH < 7.2 and pH ≥ 7.2). The primary end-point was measured using the Pittsburgh Cerebral Performance Category (CPC) scale prior to discharge from the hospital: good (CPC 1 and 2) and poor (CPC 3 to 5) neurologic outcome.

Results

Sixty-two percent of shockable CA patients with pH ≥ 7.20 had good neurological outcome as compared to 34% patients with pH < 7.20. Shockable CA patients with pH ≥ 7.20 were 3.3 times more likely to have better neurological outcome when compared to those with pH <7.20 [p = 0.013, OR 3.3, 95% CI (1.28–8.45)]. In comparison, non-shockable CA patients with p ≥ 7.20 did not have a significantly different neurological outcome as compared to those with pH < 7.20 [p = 0.97, OR 1.02, 95% CI (0.31–3.3)].

Conclusion

Presence of severe acidemia at initiation of TH in shockable CA survivors is significantly associated with poor neurological outcomes. This effect was not observed in the non-shockable CA survivors.     

S-100B is superior to NSE, BDNF and GFAP in predicting outcome of resuscitation from cardiac arrest with hypothermia treatment

Objective

To conduct a pilot study to evaluate the blood levels of brain derived neurotrophic factor (BDNF), glial fibrillary acidic protein (GFAP), neuron specific enolase (NSE) and S-100B as prognostic markers for neurological outcome 6 months after hypothermia treatment following resuscitation from cardiac arrest.

Design

Prospective observational study.

Setting

One intensive care unit at Uppsala University Hospital.

Patients

Thirty-one unconscious patients resuscitated after cardiac arrest.

Interventions

None.

Measurements and main results

Unconscious patients after cardiac arrest with restoration of spontaneous circulation (ROSC) were treated with mild hypothermia to 32-34 °C for 26 h. Time from cardiac arrest to target temperature was measured. Blood samples were collected at intervals of 1-108 h after ROSC. Neurological outcome was assessed with Glasgow-Pittsburgh cerebral performance category (CPC) scale at discharge from intensive care and again 6 months later, when 15/31 patients were alive, of whom 14 had a good outcome (CPC 1-2). Among the predictive biomarkers, S-100B at 24 h after ROSC was the best, predicting poor outcome (CPC 3-5) with a sensitivity of 87% and a specificity of 100%. NSE at 96 h after ROSC predicted poor outcome, with sensitivity of 57% and specificity of 93%. BDNF and GFAP levels did not predict outcome. The time from cardiac arrest to target temperature was shorter for those with poor outcome.

Conclusions

The blood concentration of S-100B at 24 h after ROSC is highly predictive of outcome in patients treated with mild hypothermia after cardiac arrest.     

Post-cardiac arrest serum levels of glial fibrillary acidic protein for predicting neurological outcome

Aim of the study

To investigate serum levels of glial fibrillary acidic protein (GFAP) for evaluation of neurological outcome in cardiac arrest (CA) patients and compare GFAP sensitivity and specificity to that of more studied biomarkers neuron-specific enolas (NSE) and S100B.

Method

A prospective observational study was performed in three hospitals in Sweden during 2008-2012. The participants were 125 CA patients treated with therapeutic hypothermia (TH) to 32-34 °C for 24 hours. Samples were collected from peripheral blood (n = 125) and the jugular bulb (n = 47) up to 108 hours post-CA. GFAP serum levels were quantified using a novel, fully automated immunochemical method. Other biomarkers investigated were NSE and S100B. Neurological outcome was assessed using the Cerebral Performance Categories scale (CPC) and dichotomized into good and poor outcome.

Results

GFAP predicted poor neurological outcome with 100% specificity and 14-23% sensitivity at 24, 48 and 72 hours post-CA. The corresponding values for NSE were 27-50% sensitivity and for S100B 21-30% sensitivity when specificity was set to 100%. A logistic regression with stepwise combination of the investigated biomarkers, GFAP, did not increase the ability to predict neurological outcome. No differences were found in GFAP, NSE and S100B levels when peripheral and jugular bulb blood samples were compared.

Conclusion

Serum GFAP increase in patients with poor outcome but did not show sufficient sensitivity to predict neurological outcome after CA. Both NSE and S100B were shown to be better predictors. The ability to predict neurological outcome did not increased when combining the three biomarkers.     

Testosterone related good neurologic outcome on the patients with return of spontaneous circulation after cardiac arrest: A prospective cohort study

Aim

To evaluate the gonadal hormones in patients with return of spontaneous circulation (ROSC) after cardiac arrest following prospectively good (cerebral-performance category [CPC] 1-2) and poor (CPC 3-5) neurologic outcomes.

Methods

The patients in an emergency center who had been admitted to the center's intensive care unit (ICU) after successful resuscitation following out-of-hospital cardiac arrest were prospectively identified and evaluated within the period from April 2008 to March 2011. The gonadal hormones, including progesterone, total estrogen, and testosterone, were measured and analyzed following the good and poor neurologic outcomes.

Results

A total of 142 patients were analyzed in this study. Thirty-nine (27.5%) patients had good neurologic outcomes. The gonadal hormones (progesterone, total estrogen, and testosterone) had good vs. poor neurologic outcomes of 1.039 ± 0.694 vs. 1.000 ± 0.892 ng/ml, 107.956 ± 13.163 vs. 117.060 ± 11.344 pg/ml, and 307.380 ± 33.844 vs. 189.020 ± 17.406 ng/dl, respectively. In the multiple logistic-regression analysis, the initial shockable rhythm (5.671 odds ratio [OR], 2.307-13.942 95% confidence interval [CI]), time from arrest to ROSC (0.957 OR, 0.933-0.982 95% CI), and more than 300 ng/dl of testosterone level (3.279 OR, 1.265-8.190 95% CI) were found to be related to good neurologic outcome, respectively.

Conclusion

Higher testosterone levels are related to good neurologic outcome at six months after admission in patients with spontaneous circulation after cardiac arrest. The testosterone levels may be useful prognostic tools for the postcardiac-arrest syndrome and could be used for the latter's neuroprotective treatment, but additional randomized controlled studies are needed.