A new guideline on life support and cardiopulmonary resuscitation was published by the European Resuscitation Council in late 2015. The main changes in this guideline are detailed in a recent article by Fernández-Lozano et al.1 Some of these changes are worth highlighting, such as the recommended frequency of chest compressions, which is now 100-120 bpm (in 2010 it was 100 bpm), keeping interruptions in compressions to a minimum (10-12 ventilations/min; compression:ventilation, 30:2). The depth of compressions for adults should be 5cm without exceeding 6cm. Vasopressin has been removed from the cardiac arrest algorithm in adults and all comatose adult patients should now have their temperature measured on return of spontaneous circulation, with a target range between 32 and 36°C (in 2010 it was between 32 and 34°C).
Kudenchuk et al.2 randomized 3026 patients with out-of-hospital refractory ventricular fibrillation or pulseless ventricular tachycardia to amiodarone, lidocaine, or placebo. No significant differences in prognosis were detected among the 3 study arms in terms of survival or neurological outcomes (Table).
Efficacy and Safety of Parenteral Use of Amiodarone, Lidocaine, and Placebo (Saline Solution) in Nontraumatic Cardiac Arrest (Refractory Ventricular Fibrillation or Pulseless Ventricular Tachycardia). Results the Resuscitation Outcomes Consortium Study2
Placebo n = 1059 | Pa | Amiodarone n = 974 | Pb | Lidocaine n = 993 | Pc | |
---|---|---|---|---|---|---|
Outcome Measures | ||||||
Primary outcome measure | ||||||
Survival, % | 21 | .08 | 24.4 | .70 | 23.7 | .16 |
Secondary outcome measures | ||||||
Return of spontaneous circulation, % | 34,6 | .52 | 35.9 | .07 | 39.9 | .01 |
Modified Rankin scale ≤ 3 points | 16,6 | .19 | 18.8 | .44 | 17.5 | .59 |
Admitted to hospital, % | 39,7 | .01 | 45.7 | .55 | 47 | < .001 |
Placebo | Amiodarone | Lidocaine | P | |||
---|---|---|---|---|---|---|
Adverse Events, % | ||||||
Thrombophlebitis | 0.2 | 0.1 | 0.3 | .61 | ||
Anaphylaxis within 24 hours | 0 | 0 | 0 | -- | ||
Clinical seizure | 3.7 | 3.2 | 5.1 | .07 | ||
Temporary cardiac pacing | 2.7 | 4.9 | 3.2 | .02 | ||
Death before discharge | 78.8 | 75.3 | 75.7 | .16 | ||
Any adverse events within first 24 hours or death before discharge | 80.4 | 78.3 | 78.0 | .20 |
A retrospective substudy of the Japanese Utstein registry in 282183 adult patients with out-of-hospital cardiac arrest showed that prehospital cardiopulmonary resuscitation maneuvers initiated by bystanders should continue for at least 40minutes from notification of the emergency medical services, with at least 33minutes of resuscitation maneuvers after arrival on the scene.3 Prior action for the above duration achieved an improvement in survival and neurological outcomes at 30 days.
According to the United States National Cardiovascular Data Registry,4 in patients in cardiogenic shock (CS) resulting from acute myocardial infarction who survived hospitalization (n=5555 [4.9%]), deaths attributable to CS occurred mainly in first 60 days after discharge (9.6% versus 5.5%; adjusted hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.46-1.80). In contrast, once the first 60 days had elapsed, mortality did not differ significantly between the 2 groups (taking patients without CS as the reference group, adjusted HR = 1.08; 95% CI, 1.00-1.18).
The results of 2 clinical trials on renal replacement therapy for critically ill patients with acute kidney injury (AKI) have been published: ELAIN5 and AKIKI.6 The ELAIN study enrolled 231 patients with AKI at a German site and randomized them to early or delayed renal replacement therapy. Early therapy was defined as therapy initiated within 8hours of diagnosis of stage 2 AKI according to the Kidney Disease: Improving Global Outcomes (KDIGO) classification. Delayed replacement therapy was indicated within 12hours of diagnosis of stage 3 AKI. Significant differences in favor of early therapy compared with delayed therapy were found in terms of lower mortality (primary outcome measure) at 90 days (39.3% versus 52.7%; P=.03).
Unlike the results of the ELAIN study, the multicenter French clinical trial AKIKI reported a similar mortality rate with both early and delayed strategies, although the design of this study differed substantially from that of the ELAIN study.5 In the AKIKI study,6 620 patients with invasive mechanical ventilation, perfusion of adrenaline/noradrenaline, or both who developed AKI during their stay in the intensive care unit were randomized 1:1 to an early or delayed strategy.6 The early strategy consisted of hemodialysis sessions (continuous or intermittent) within 6hours of documentation of stage 3 AKI according to the KDIGO classification. In the delayed strategy, renal replacement therapy was initiated in the event that AKI persisted for more than 72hours with at least 1 of the following conditions: blood urea nitrogen > 112mg/dL (equivalent to 240 mg/dL serum urea), serum potassium > 5.5 mmol/L despite medical treatment, metabolic acidosis, oliguria, or pulmonary edema. The primary outcome measure, survival at 60 days, did not differ significantly between the 2 groups (48.5% versus 49.7%; P=.79).
CONFLICTS OF INTERESTE. Abu-Assi is Associate Editor of Revista Española de Cardiología.