Is hypothermia after cardiac arrest effective in both shockable and nonshockable patients?: insights from a large registry.

BACKGROUND: Although the level of evidence of improvement is significant in cardiac arrest patients resuscitated from a shockable rhythm (ventricular fibrillation or pulseless ventricular tachycardia [VF/Vt]), the use of therapeutic mild hypothermia (TMH) is more controversial in nonshockable patients (pulseless electric activity or asystole [PEA/asystole]). We therefore assessed the prognostic value of hypothermia for neurological outcome at hospital discharge according to first-recorded cardiac rhythm in a large cohort. METHODS AND RESULTS: Between January 2000 and December 2009, data from 1145 consecutive out-of-hospital cardiac arrest patients in whom a successful resuscitation had been achieved were prospectively collected. The association of TMH with a good neurological outcome at hospital discharge (cerebral performance categories level 1 or 2) was quantified by logistic regression analysis. TMH was induced in 457/708 patients (65%) in VF/Vt and in 261/437 patients (60%) in PEA/asystole. Overall, 342/1145 patients (30%) reached a favorable outcome (cerebral performance categories level 1 or 2) at hospital discharge, respectively 274/708 (39%) in VF/Vt and 68/437 (16%) in PEA/asystole (P<0.001). After adjustment, in VF/Vt patients, TMH was associated with increased odds of good neurological outcome (adjusted odds ratio, 1.90; 95% confidence interval, 1.18 to 3.06) whereas in PEA/asystole patients, TMH was not significantly associated with good neurological outcome (adjusted odds ratio, 0.71; 95% confidence interval, 0.37 to 1.36). CONCLUSIONS: In this large cohort of cardiac arrest patients, hypothermia was independently associated with an improved outcome at hospital discharge in patients presenting with VF/Vt. By contrast, TMH was not associated with good outcome in nonshockable patients. Further investigations are needed to clarify this lack of efficiency in PEA/asystole.

Can early cardiac troponin I measurement help to predict recent coronary occlusion in out-of-hospital cardiac arrest survivors?

OBJECTIVE: Recent guidelines recommend the immediate performance of a coronary angiography when an acute myocardial infarction is suspected as a cause of out-of-hospital cardiac arrest. However, prehospital factors such as postresuscitation electrocardiogram pattern or clinical features are poorly sensitive in this setting. We searched to evaluate if an early measurement of cardiac troponin I can help to detect a recent coronary occlusion in out-of-hospital cardiac arrest. DESIGN: Retrospective analysis of a prospective electronic registry database. SETTING: University cardiac arrest center. PATIENTS: Between January 2003 and December 2008, 422 out-of-hospital cardiac arrest survivors without obvious extra-cardiac cause have been consecutively studied. An immediate coronary angiography has been systematically performed. The primary outcome was the finding of a recent coronary occlusion. INTERVENTION: First, blood cardiac troponin I levels at admission were analyzed to assess the optimum cutoff for identifying a recent coronary occlusion. Second, a logistic regression was performed to determine early predictive factors of a recent coronary occlusion (including cardiac troponin I) and their respective contribution. MEASUREMENTS AND MAIN RESULTS: An ST-segment elevation was present in 127 of 422 patients (30%). During coronary angiography, a recent occlusion has been detected in 193 of 422 patients (46%). The optimum cardiac troponin I threshold was determined at 4.66 ng·mL(-1) (sensitivity 66.7%, specificity 66.4%). In multivariate analyses, in addition of smoking and epinephrine initial dose, cardiac troponin I (odds ratio 3.58 [2.03-6.32], p < .001) and ST-segment elevation (odds ratio 10.19 [5.39-19.26], p < .001) were independent predictive factors of a recent coronary occlusion. CONCLUSIONS: In this large cohort of out-of-hospital cardiac arrest patients, isolated early cardiac troponin I measurement is modestly predictive of a recent coronary occlusion. Furthermore, the contribution of this parameter even in association with other factors does not seem helpful to predict recent occlusion. As a result and given the high benefit of percutaneous coronary intervention for such patients, the dosage of cardiac troponin I at admission could not help in the decision of early coronary angiogram.

Feasibility of right ventricular longitudinal systolic function evaluation with transthoracic echocardiographic indices derived from tricuspid annular motion: a preliminary study in acute respiratory distress syndrome.

INTRODUCTION: Assessment of right ventricular (RV) function in patients with acute respiratory distress syndrome (ARDS) remains challenging. Transthoracic echocardiographic (TTE) indices based on longitudinal systolic RV function are now considered as a reliable evaluation of RV function. We investigated feasibility of two methods in ARDS patients. METHODS: Prospective observational study. TTE was performed after 12-36 hours of mechanical ventilation. Feasibility of tricuspid annular motion (S(t) ), tricuspid annular plane systolic excursion (TAPSE) was compared to usual two-dimensional (2D) study: fractional area change (RV(FAC) ) and ratio of right to left ventricular end-diastolic area (RVEDA/LVEDA). RESULTS: Fifty patients were investigated, with TTE possible in all but two patients. Feasibility was 62% for RV(FAC), 72% for RVEDA/LVEDA, and 96% for TAPSE and S(t). RV dilatation (RVEDA/LVEDA ≥ 0.60) was found in 16 patients, including 4 patients with acute cor pulmonale. A longitudinal RV dysfunction (TAPSE < 12 mm or S(t) < 11.5 cm/sec) was suspected in 30% of patients. Relation between both longitudinal indices was modest (r(2) = 0.36, P < 0.001). TAPSE (but not S(t) ) was found poorly related to RV(FAC) (r(2) = 0.27, P = 0.03). Both indices were related to LV function (S(t) : r(2) = 0.27, TAPSE: r(2) = 0.17, both P < 0.05). CONCLUSION: Despite a superior feasibility than 2D study, our results suggest that both indices may not bring identical information to echo study. TAPSE may be more adapted to ICU use than S(t) . Both should be further investigated in terms of analysis of RV function and ventricular interdependence. Their relations with LV function may limit their use as sole markers of RV function in this population.

Sudden cardiac arrest: ECG repolarization after resuscitation.

INTRODUCTION: Early repolarization (ERep) abnormalities on electrocardiogram (ECG) are common immediately following cardiac arrest. We characterized and correlated electrocardiographic repolarization abnormalities immediately after cardiac arrest with acute coronary angiography. METHODS AND RESULTS: We studied 225 consecutive patients presenting with out-of-hospital cardiac arrest. All these patients had successful cardiopulmonary resuscitation and acute coronary angiography. The first ECG recorded after successful resuscitation was analyzed by two independent cardiologists. Patients were categorized according to their repolarization pattern. Pattern 1: No ST segment elevation or ERep. Pattern 2: ST segment elevation without ERep. Pattern 3: ST segment elevation and ERep. Pattern 4: ERep only. Patterns 1, 2, 3, and 4 were found in 112 (50%), 74 (33%), 19 (8%), and 20 (9%) patients, respectively. Cardiac arrest was due to acute myocardial ischemia in 45%, 82%, 39%, and 15% of patients in groups 1, 2, 3 and 4, respectively (P < 0.0001). Sensitivity and specificity of pattern 2 was 50% and 88%, respectively, for acute coronary lesion, whereas isolated ERep pattern occurred in 9% of cases and was associated with a nonischemic event (80%). Among 65 patients (29%) who survived, 7% of patients with pattern 1, 13% with pattern 2, 60% with pattern 3, and 88% with pattern 4 exhibited ERep on ECG during the follow-up. CONCLUSION: In the context of cardiac resuscitation, an ECG with ST elevation favors acute myocardial infarction, whereas the presence of ERep is a marker of a nonischemic event and future ERep syndrome.

Reducing risk of stroke in patients with acute coronary syndrome: is screening for asymptomatic carotid disease useful?

Stroke is a rare but severe event after acute coronary syndrome. Relations between both arterial territories are still discussed but prevalence of asymptomatic carotid stenosis potentially implicated in the mechanism of stroke is under-investigated. This study aimed to determine the prevalence of asymptomatic carotid stenosis in that population and review the value of screening in a view to potential surgical correction or other preventive therapies. Systematic carotid Doppler ultrasound screening was implemented on 152 consecutive patients admitted to the intensive care unit due to acute coronary syndrome. Fifty-two percent of patients had at least one carotid artery stenosis determined using the NASCET method. Forty-three percent had at least one carotid stenosis <30%, 6% had mild (30-60%) stenosis, and 2.6% had high-grade (>60%) stenosis. Existence of carotid stenosis was associated with age, diabetes mellitus, hypertension, and with the extent of the coronary atherosclerosis (left main artery stenosis). In multivariate analysis, age and diabetes were independently associated with existence of a carotid stenosis. When ultrasound screening was restricted to patients identified by multivariate analysis, the prevalence of carotid stenosis potentially requiring surgical treatment rose to 4.6%. The frequency of asymptomatic carotid atherosclerosis was high in this population but lesions were mild. While the small number of high-grade lesions indicates that systematic screening is not to be recommended, screening of patients aged >65 years or with diabetes, or both, with a view to surgery may be envisaged, since the role of mild stenosis in the occurrence of stroke remains debatable.

Fatal QT interval.

A 21-year-old woman, without medical history, was admitted after cardiac arrest. Cardiopulmonary resuscitation and use of semiautomatic defibrillator quickly restored sinus rhythm. Clinical examination was normal with no cardiac murmur or abnormal heart sound. Electrocardiogram revealed sinus rhythm with short QT interval. Serum electrolytes and arterial blood gazes were normal. One hour after admission, lethal ventricular fibrillation occurred. Factors that shorten QT interval including increase in heart rate, hyperthermia, increased calcium, or potassium plasma levels and acidosis were excluded. Short-QT syndrome has been recently recognized as a genetic ion channel dysfunction leading to an abbreviation of action potential and a potential substrate for arrhythmias. This syndrome is characterized by a short QT interval (typically <320 milliseconds), associated with a high incidence of sudden death, syncope, or atrial fibrillation in individuals with an apparently normal heart. Implementation of an internal cardiac defibrillator remains the only effective preventive treatment.

Prognosis of cirrhotic patients admitted to intensive care unit: a meta-analysis.

BACKGROUND: The best predictors of short- and medium-term mortality of cirrhotic patients receiving intensive care support are unknown. METHODS: We conducted meta-analyses from 13 studies (2523 cirrhotics) after selection of original articles and response to a standardized questionnaire by the corresponding authors. End-points were in-ICU, in-hospital, and 6-month mortality in ICU survivors. A total of 301 pooled analyses, including 95 analyses restricted to 6-month mortality among ICU survivors, were conducted considering 249 variables (including reason for admission, organ replacement therapy, and composite prognostic scores). RESULTS: In-ICU, in-hospital, and 6-month mortality was 42.7, 54.1, and 75.1%, respectively. Forty-eight patients (3.8%) underwent liver transplantation during follow-up. In-ICU mortality was lower in patients admitted for variceal bleeding (OR 0.46; 95% CI 0.36-0.59; p < 0.001) and higher in patients with SOFA > 19 at baseline (OR 8.54; 95% CI 2.09-34.91; p < 0.001; PPV = 0.93). High SOFA no longer predicted mortality at 6 months in ICU survivors. Twelve variables related to infection were predictors of in-ICU mortality, including SIRS (OR 2.44; 95% CI 1.64-3.65; p < 0.001; PPV = 0.57), pneumonia (OR 2.18; 95% CI 1.47-3.22; p < 0.001; PPV = 0.69), sepsis-associated refractory oliguria (OR 10.61; 95% CI 4.07-27.63; p < 0.001; PPV = 0.76), and fungal infection (OR 4.38; 95% CI 1.11-17.24; p < 0.001; PPV = 0.85). Among therapeutics, only dopamine (OR 5.57; 95% CI 3.02-10.27; p < 0.001; PPV = 0.68), dobutamine (OR 8.92; 95% CI 3.32-23.96; p < 0.001; PPV = 0.86), epinephrine (OR 5.03; 95% CI 2.68-9.42; p < 0.001; PPV = 0.77), and MARS (OR 2.07; 95% CI 1.22-3.53; p = 0.007; PPV = 0.58) were associated with in-ICU mortality without heterogeneity. In ICU survivors, eight markers of liver and renal failure predicted 6-month mortality, including Child-Pugh stage C (OR 2.43; 95% CI 1.44-4.10; p < 0.001; PPV = 0.57), baseline MELD > 26 (OR 3.97; 95% CI 1.92-8.22; p < 0.0001; PPV = 0.75), and hepatorenal syndrome (OR 4.67; 95% CI 1.24-17.64; p = 0.022; PPV = 0.88). CONCLUSIONS: Prognosis of cirrhotic patients admitted to ICU is poor since only a minority undergo liver transplant. The prognostic performance of general ICU scores decreases over time, unlike the Child-Pugh and MELD scores, even recorded in the context of organ failure. Infection-related parameters had a short-term impact, whereas liver and renal failure had a sustained impact on mortality.

Haemodynamic response to crystalloids or colloids in shock: an exploratory subgroup analysis of a randomised controlled trial.

OBJECTIVE: To compare the haemodynamic effect of crystalloids and colloids during acute severe hypovolaemic shock. DESIGN: Exploratory subgroup analysis of a multicentre randomised controlled trial (Colloids Versus Crystalloids for the Resuscitation of the Critically Ill, CRISTAL, ClinicalTrials.gov NCT00318942). SETTING: CRISTAL was conducted in intensive care units in Europe, North Africa and Canada. PARTICIPANTS: Current analysis included all patients who had a pulmonary artery catheter in place at randomisation. 220 patients (117 received crystalloids vs 103 colloids) underwent pulmonary artery catheterisation. INTERVENTION: Crystalloids versus colloids for fluid resuscitation in hypovolaemic shock. OUTCOME MEASURES: Haemodynamic data were collected at the time of randomisation and subsequently on days 1, 2, 3, 4, 5, 6 and 7. RESULTS: Median cumulative volume of fluid administered during the first 7 days was higher in the crystalloids group than in the colloids group (3500 (2000-6000) vs 2500 (1000-4000) mL, p=0.01). Patients in the colloids arm exhibited a lower heart rate over time compared with those allocated to the crystalloids arm (p=0.014). There was no significant difference in Cardiac Index (p=0.053), mean blood pressure (p=0.4), arterial lactates (p=0.9) or global Sequential Organ Failure Assessment score (p=0.3) over time between arms. CONCLUSIONS: During acute severe hypovolaemic shock, patients monitored by a pulmonary artery catheter achieved broadly similar haemodynamic outcomes, using lower volumes of colloids than crystalloids. The heart rate was lower in the colloids arm.

Constipation incidence and impact in medical critical care patients: importance of the definition criterion.

BACKGROUND: Constipation incidence and impact remain controversial in the ICU. This may depend on the definition criterion used in the previous studies on the field. We aimed to determine the frequency and significance of constipation according to its definition criterion. METHODS: This is a prospective observational study. Adult patients without a cause of transit time modification and laxative intake within the first 3 days were screened. Constipation was defined by a first stool passage occurring after 3 days of ICU stay. Thereafter, we identified two subgroups of patients: absence of stool passage more than 3 days but less than 6 days (3-day subgroup), and no stool passage for 6 days or more (6-day subgroup). Survival, length of stay and time spent under mechanical ventilation (MV) were compared according to constipation status. RESULTS: Among 189 included patients [age 60.8 (49.5-74.2) years, SAPS II 44 (34-53)], 98 (51.9%) exhibited constipation (3-day subgroup n=53, 6-day subgroup n=45). Constipated patients were more likely to receive MV, sedation, vasopressors, enteral nutrition and neuromuscular blocking agents. ICU length of stay and time spent under MV was longer in the 6-day subgroup but not in the 3-day subgroup of patients. CONCLUSION: With regard to outcomes, defining constipation by the absence of stool passage less than 6 days after ICU admission does not identify a specific subset of population. Further studies on the management of this condition should focus on these 'long-term' constipated patients.

Handgrip Strength Predicts Difficult Weaning But Not Extubation Failure in Mechanically Ventilated Subjects.

BACKGROUND: Muscle weakness, defined by the Medical Research Council scale, has been associated with delay in mechanical ventilation weaning. In this study, we evaluated handgrip strength as a prediction tool in weaning outcome. METHODS: This was a 1-y prospective study in 2 ICUs in 2 university hospitals. Adult patients who were on mechanical ventilation for at least 48 h and eligible for mechanical ventilation weaning were screened for inclusion. Handgrip strength was evaluated using a handheld dynamometer before each spontaneous breathing trial (SBT). Attending physicians were unaware of handgrip strength and decided on extubation according to guidelines. RESULTS: Eighty-four subjects were included (median age 66 [53-79] y, with a median Simplified Acute Physiology Score II of 49 [37-63]). At the first evaluation, median handgrip strength was significantly associated with weaning outcome as defined by international guidelines: simple (20 [12-26] kg), difficult (12 [6-21] kg), or prolonged (6 [3-11] kg) weaning (P = .008). Time to liberation from mechanical ventilation and ICU stay were significantly longer for subjects classified as having muscle weakness according to the handgrip strength-derived definition (P = .02 and P = .03, respectively). In multivariate analysis, known history of COPD (odds ratio [OR] 5.48, 95% CI 1.44-20.86, P = .01), sex (OR 6.16, 95% CI 1.64-23.16, P = .007), and handgrip strength at the first SBT (OR 0.89, 95% CI 0.85-0.97, P = .004) were significantly associated with difficult or prolonged weaning. Extubation failure, as defined by re-intubation or unscheduled noninvasive ventilation within 48 h after extubation, occurred 14 times after 92 attempts, leading to an extubation failure rate of 15%. No association was found between handgrip strength and extubation outcome. CONCLUSIONS: Muscle weakness, assessed by handgrip strength, is associated with difficult or prolonged mechanical ventilation weaning and ICU stay, but not with extubation outcome.