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 Active intensive care was withdrawn in 50 patients based on a statement of poor neurological prognosis at least 72 h after rewarming.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.     

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%.     

Procalcitonin after cardiac arrest – An indicator of severity of illness,ischemia-reperfusion injury and outcome

Aim

To investigate serial serum concentrations of procalcitonin (PCT) and C-reactive protein (CRP) in patients treated with mild hypothermia after cardiac arrest, and to study their association to severe infections, post cardiac arrest syndrome (PCAS) and long-term outcome.

Methods

Serum samples from cardiac arrest patients treated with mild hypothermia were collected serially at admission, 2, 6, 12, 24, 36, 48 and 72 h after cardiac arrest. PCT and CRP concentrations were determined and tested for association with three definitions of infection, two surrogate markers of PCAS (circulation-SOFA and time to return of spontaneous circulation (ROSC)) and cerebral performance category (CPC) at six months.

Results

Eighty-four patients were included. PCT displayed an earlier release pattern than CRP with a significant increase within 2 h, increasing further at 6 h and onwards in patients with poor outcome. CRP increased later and continued to rise during the study period. PCT was strongly associated with circulation-SOFA and time to ROSC, and predicted a poor neurologic outcome with high accuracy (area under the receiver operating characteristic curve of 0.88, 0.86 and 0.87 at 12, 24 and 48 h respectively). No association of PCT or CRP to infection was observed.

Conclusion

Our results suggest that PCT is released early after resuscitation following cardiac arrest, is associated with markers of PCAS but not with infection, and is an accurate predictor of poor outcome. Validation of these findings in larger studies is warranted.     

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.     

Serum glial fibrillary acidic protein as a predictive biomarker of neurological outcome after cardiac arrest

Aim of the study

Serum glial fibrillary acidic protein (GFAP) has recently been identified as a specific predictor of brain damage and neurological outcome in patients with head trauma. In this study, serum GFAP was assessed as a predictor of neurological outcome in post-cardiac-arrest (PCA) patients.

Methods

This study was a retrospective, single-medical-center analysis, conducted in the intensive care unit of a university hospital. Forty-four sequential PCA patients with cardiogenic or non-cardiogenic arrest were included. The patients were treated with or without therapeutic hypothermia (TH). Serum samples were collected from the patients at 12, 24, and 48 h after the return of spontaneous circulation (ROSC). Serum GFAP concentrations were measured by enzyme-linked immunosorbent assay and compared in patients with good and poor neurological outcomes, evaluated over a period of 6 months using Glasgow Outcome Scale.

Results

Serum GFAP was significantly higher in patients with a poor outcome at 12 and 24 h without TH and at 48 h with TH (P < 0.05). GFAP (>0.1 ng dL⁻¹) was a specific predictor of poor neurological outcome at 6 months with or without TH treatment.

Conclusions

Although this study is preliminary, serum GFAP after ROSC reflected a poor neurological outcome in PCA patients.     

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.     

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.     

Therapeutic hypothermia and vasopressor dependency after cardiac arrest

Objective

Clinical trials of therapeutic hypothermia (TH) after cardiac arrest excluded patients with persistent hemodynamic instability after return of spontaneous circulation (ROSC), and thus equipoise may exist regarding use of TH in these patients. Our objective was to determine if TH is associated with worsening hemodynamic instability among patients who are vasopressor-dependent after ROSC.

Methods

We performed a prospective observational study in vasopressor-dependent post-cardiac arrest patients. Inclusion criteria were age >17, non-trauma cardiac arrest, comatose after ROSC, and persistent vasopressor dependence. The decision to initiate TH (33–34 °C) was made by the treating physician. We measured cumulative vasopressor index (CVI) and mean arterial pressure (MAP) every 15 min during the first 6 h after ROSC. The outcome measures were change in CVI (primary outcome) and MAP (secondary outcome) over time. We graphed median CVI and MAP over time for the treated and not treated cohorts, and used propensity adjusted repeated measures mixed models to test for an association between TH induction and change in CVI or MAP over time.

Results

Seventy-five post-cardiac arrest patients were included (35 treated; 40 not treated). We observed no major differences in CVI or MAP over time between the treated and not treated cohorts. In the mixed models we found no statistically significant association between TH induction and changes in CVI or MAP.

Conclusion

In patients with vasopressor-dependency after cardiac arrest, the induction of hypothermia was not associated with a decrease in mean arterial pressure or increase in vasopressor requirement.     

Prognostic value of electrographic postanoxic status epilepticus in comatose cardiac-arrest survivors in the therapeutic hypothermia era

Background

The independent prognostic significance of postanoxic status epilepticus (PSE) has not been evaluated prospectively since the introduction of therapeutic hypothermia. We studied 1-year functional outcomes and their determinants in comatose survivors of cardiac arrest (CA), with special attention to PSE.

Methods

106 comatose CA survivors admitted to the intensive care unit in 2005–2010 were included in a prospective observational study. The main outcome measure was a Cerebral Performance Category scale (CPC) of 1 or 2 (favorable outcome) 1 year after CA.

Results

CA occurred out-of-hospital in 89 (84%) patients and was witnessed from onset in 94 (89%). Median times were 6 min (IQR, 0–11) from CA to first-responder arrival and 23 min (14–40) from collapse to return of spontaneous circulation. PSE was diagnosed in 33 (31%) patients at a median of 39 h (4–49) after CA. PSE was refractory in 24 (22%) cases and malignant in 19 (20%). After 1 year, 31 (29.3%) patients had favorable outcomes including 2 (6.44%) with PSE. Factors independently associated with poor outcome (CPC ≥ 3) were PSE (odds ratio [OR], 14.28; 95% confidence interval [95% CI], 2.77–50.0; P = 0.001), time to restoration of spontaneous circulation (OR, 1.04/min; 95% CI, 1–1.07; P = 0.035), and LOD score on day 1 (OR, 1.28/point; 95% CI, 1.08–1.54; P = 0.003).

Conclusion

PSE strongly and independently predicts a poor outcome in comatose CA survivors receiving therapeutic hypothermia, but some patients with PSE survive with good functional outcomes. PSE alone is not sufficient to predict failure to awaken after CA in the era of therapeutic hypothermia.     

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.     

Bispectral Index to Predict Neurological Outcome Early After Cardiac Arrest

Aim of the study

To address the value of continuous monitoring of bispectral index (BIS) to predict neurological outcome after cardiac arrest.

Methods

In this prospective observational study in adult comatose patients treated by therapeutic hypothermia after cardiac arrest we measured bispectral index (BIS) during the first 24 hours of intensive care unit stay. A blinded neurological outcome assessment by cerebral performance category (CPC) was done 6 months after cardiac arrest.

Results

Forty-six patients (48%) had a good neurological outcome at 6-month, as defined by a cerebral performance category (CPC) 1-2, and 50 patients (52%) had a poor neurological outcome (CPC 3-5). Over the 24 h of monitoring, mean BIS values over time were higher in the good outcome group (38 ± 9) compared to the poor outcome group (17 ± 12) (p < 0.001). Analysis of BIS recorded every 30 minutes provided an optimal prediction after 12.5 h, with an area under the receiver operating characteristic curve (AUC) of 0.89, a specificity of 89% and a sensitivity of 86% using a cut-off value of 23. With a specificity fixed at 100% (sensitivity 26%) the cut-off BIS value was 2.4 over the first 271 minutes. In multivariable analyses including clinical characteristics, mean BIS value over the first 12.5 h was a predictor of neurological outcome (p = 6E-6) and provided a continuous net reclassification index of 1.28% (p = 4E-10) and an integrated discrimination improvement of 0.31 (p = 1E-10).

Conclusions

Mean BIS value calculated over the first 12.5 h after ICU admission potentially predicts 6-months neurological outcome after cardiac arrest.     

New treatment bundles improve survival in out-of-hospital cardiac arrest patients: A historical comparison

Introduction

Before the introduction of the new international cardiac arrest treatment guidelines in 2005, patients with out-of-hospital cardiac arrest (OHCA) of cardiac origin in Northern Italy had very poor prognosis. Since 2006, a new bundle of care comprising use of automated external defibrillators (AEDs) and therapeutic hypothermia (TH) was started, while extracorporeal CPR program (ECPR) for selected refractory CA and dispatcher-assisted cardio-pulmonary resuscitation (CPR) was started in January 2010.

Objectives

We hypothesized that a program of bundled care might improve outcome of OHCA patients.

Methods

We analyzed data collected in the OHCA registry of the MB area between September 2007 and August 2011 and compared this with data from 2000 to 2003.

Results

Between 2007 and 2011, 1128 OHCAs occurred in the MB area, 745 received CPR and 461 of these had a CA of presumed cardiac origin. Of these, 125 (27%) achieved sustained ROSC, 60 (13%) survived to 1 month, of whom 51 (11%) were discharged from hospital with a good neurological outcome (CPC ≤ 2), and 9 with a poor neurological outcome (CPC > 2).Compared with data from the 2000 to 2003 periods, survival increased from 5.6% to 13.01% (p < 0.0001). In the 2007–2011 group, low-flow time and bystander CPR were independent markers of survival.

Conclusions

OHCA survival has improved in our region. An increased bystander CPR rate associated with dispatcher-assisted CPR was the most significant cause of increased survival, but duration of CA remains critical for patient outcome.     

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.     

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.     

Effects of adenosine monophosphate on induction of therapeutic hypothermia and neuronal damage after cardiopulmonary resuscitation in rats

Background

Animal studies and pathophysiological considerations suggest that therapeutic hypothermia after cardiopulmonary resuscitation is the more effective the earlier it is induced. Therefore this study is sought to examine whether pharmacological facilitated hypothermia by administration of 5′-adenosine monophosphate (AMP) is neuroprotective in a rat model of cardiac arrest (CA) and resuscitation.

Methods

Sixty-one rats were subjected to CA. After 6 min of ventricular fibrillation advanced cardiac life support was started. After successful return of spontaneous circulation (ROSC, n = 40), animals were randomized either to placebo group (n = 14) or AMP group (800 mg/kg body weight, n = 14). Animals were kept at an ambient temperature of 18 °C for 12 h after ROSC and core body temperature was measured using a telemetry temperature probe. Neuronal damage was analyzed by counting Nissl-positive (i.e. viable) neurons and TUNEL-positive (i.e. apoptotic) cells in coronal brain sections 7 days after ROSC. Functional status evaluated on days 1, 3 and 7 after ROSC by a tape removal test.

Results

Time until core body temperature dropped to <34.0 °C was 31 min [28; 45] in AMP-treated animals and 125 min [90; 180] in the control group (p = 0.003). Survival until 7 days after ROSC was comparable in both groups. Also number of Nissl-positive cells (AMP: 1 [1; 7] vs. placebo: 2 [1; 3] per 100 pixel; p = 0.66) and TUNEL-positive cells (AMP: 56 [44; 72] vs. placebo: 53 [41; 67] per 100 pixel; p = 0.70) did not differ. Neither did AMP affect functional neurological outcome up to 7 days after ROSC. Mean arterial pressure 20 min after ROSC was 49 [45; 55] mmHg in the AMP group in comparison to 91 [83; 95] mmHg in the control group (p < 0.001).

Conclusion

Although application of AMP reduced the time to reach a core body temperature of <34 °C neither survival was improved nor neuronal damage attenuated. Reason for this is probably induction of marked hypotension as an adverse reaction to AMP treatment.     

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.     

Duplex sonography of cerebral blood flow after cardiac arrest—A prospective observational study

Aim

Despite successful resuscitation, cardiac arrest (CA) often has a poor clinical prognosis. Different diagnostic tools have been established to predict patients’ outcome. However, their sensitivity remains low. Assessment of cerebral perfusion by duplex ultrasound might provide additional information regarding the extent of neuronal damage. The aim of the present study was to analyse the changes of global cerebral blood flow (CBF) and intracranial blood flow parameters in the acute stage after CA and its correlation with patients’ outcome.

Methods

We investigated 54 patients (17–85 years, mean age: 63 ± 17 years) after CA with return of spontaneous circulation on an intensive care unit. All patients received therapeutic hypothermia (TH) for 24 h after CA and reanimation. Serial measurements of CBF as well as intracranial blood flow velocities and pulsatility indices of the middle cerebral artery and the basal vein of Rosenthal were performed within the first 10 days using duplex ultrasound. Clinical outcome was measured using the Cerebral Performance Category.

Results

Measurements were successful in 53 patients. CBF values differed between 210 and 1100 ml/min. 24 patients (45%) attained a good outcome. No correlation between CBF or intracranial blood flow characteristics and outcome was found. Neither cerebral hypo- nor hyperperfusion was associated with a fatal outcome.

Conclusion

Cerebral perfusion varies widely after CA. Neither hypo- nor hyperperfusion seems to be an independent risk factor for poor outcome. Duplex ultrasound of cerebral haemodynamics after CA is suitable but probably of limited prognostic value.     

Serum procalcitonin as a marker of post-cardiac arrest syndrome and long-term neurological recovery,but not of early-onset infections,in comatose post-anoxic patients treated with therapeutic hypothermia

Objective

To examine the relationship of early serum procalcitonin (PCT) levels with the severity of post-cardiac arrest syndrome (PCAS), long-term neurological recovery and the risk of early-onset infections in patients with coma after cardiac arrest (CA) treated with therapeutic hypothermia (TH).

Methods

A prospective cohort of adult comatose CA patients treated with TH (33 °C, for 24 h) admitted to the medical/surgical intensive care unit, Lausanne University Hospital, was studied. Serum PCT was measured early after CA, at two time-points (days 1 and 2). The SOFA score was used to quantify the severity of PCAS. Diagnosis of early-onset infections (within the first 7 days of ICU stay) was made after review of clinical, radiological and microbiological data. Neurological recovery at 3 months was assessed with Cerebral Performance Categories (CPC), and was dichotomized as favorable (CPC 1–2) vs. unfavorable (CPC 3–5).

Results

From December 2009 to April 2012, 100 patients (median age 64 [interquartile range 55–73] years, median time from collapse to ROSC 20 [11–30] min) were studied. Peak PCT correlated with SOFA score at day 1 (Spearman's R = 0.44, p < 0.0001) and was associated with neurological recovery at 3 months (peak PCT 1.08 [0.35–4.45] ng/ml in patients with CPC 1–2 vs. 3.07 [0.89–9.99] ng/ml in those with CPC 3–5, p = 0.01). Peak PCT did not differ significantly between patients with early-onset vs. no infections (2.14 [0.49–6.74] vs. 1.53 [0.46–5.38] ng/ml, p = 0.49).

Conclusions

Early elevations of serum PCT levels correlate with the severity of PCAS and are associated with worse neurological recovery after CA and TH. In contrast, elevated serum PCT did not correlate with early-onset infections in this setting.     

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.     

Prognostic implication of initial coagulopathy in out-of-hospital cardiac arrest

Objective

We sought to investigate the prognostic implication of early coagulopathy represented by initial DIC score in out-of-hospital cardiac arrest (OHCA).

Methods

OHCA registry was analyzed to identify patients with ROSC without recent use of anticoagulant between 2008 and 2011. Patients were assessed for prehosptial factors, initial laboratory results and therapeutic hypothermia. Outcome variables were survival discharge, 6-month CPC and survival duration within the first week after ROSC. Logistic regression and Cox proportional hazards models were used for both univariable and multivariable analysis.

Results

Among 273 eligible patients, initial DIC score was available in 252 (92.3%). Higher DIC score was associated with increased inhospital death (odds ratio [OR], 1.89 per unit; 95% confidence interval [CI], 1.48–2.41) and unfavorable long-term outcome (6-month CPC 3–5; OR, 2.21 per unit; 95% CI, 1.60–3.05). The adjusted ORs for both outcomes were 1.61 (95% CI, 1.17–2.22) and 1.84 (95% CI, 1.26–2.67), respectively. We categorized DIC score in five groups as <3, 3, 4, 5 and >5 and analyzed differential mortality risk using Cox proportional hazards model. Compared with reference group (DIC score < 3), the adjusted HR for early mortality in each remaining group was 1.96 (95% CI, 1.13–3.40), 2.26 (95% CI, 1.27–4.02), 2.77 (95% CI, 1.58–4.85) and 4.29 (95% CI, 2.22–8.30), respectively (p-trend < 0.001). The area under the receiver operating characteristic of DIC score for prediction of unfavorable long-term outcome was 0.79 (95% CI, 0.69–0.88).

Conclusion

Increased initial DIC score in OHCA was an independent predictor for poor outcomes and early mortality risk.