BACKGROUND: Epinephrine is recommended in advanced cardiac life support guidelines for use in adult cardiac arrest, and has been used in cardiopulmonary resuscitation since 1896. Yet, despite its long time use and incorporation into guidelines, epinephrine suffers from a paucity of evidence regarding its influence on survival. This critical review was conducted to address the knowledge deficit regarding epinephrine in out-of-hospital cardiac arrest and its effect on return of spontaneous circulation, survival to hospital discharge, and neurological performance. METHODS: The EMBASE and MEDLINE (through the Pubmed interface) databases, and the Cochrane library were searched with the key words "epinephrine", "cardiac arrest" and variations of these terms. Original research studies concerning epinephrine use in adult, out-of-hospital cardiac arrest were selected for further review. RESULTS: The search yielded nine eligible studies based on inclusion criteria. This includes five prospective cohort studies, one retrospective cohort study, one survival analysis, one case control study, and one RCT. The evidence clearly establishes an association between epinephrine and increased return of spontaneous circulation, the data were conflicting concerning survival to hospital discharge and neurological outcome. CONCLUSIONS: The results of this review exhibit the paucity of evidence regarding the use of epinephrine in out of hospital cardiac arrest. There is currently insufficient evidence to support or reject its administration during resuscitation. Larger sample, placebo controlled, double blind, randomized control trials need to be performed to definitively establish the effect of epinephrine on both survival to hospital discharge and the neurological outcomes of treated patients.

BACKGROUND:Atrial fibrillation (AF) is the most common arrhythmia treated in the emergency department (ED), with primary electrical cardioversion (PEC) the preferred method of rhythm control. Anecdotally, patients undergoing ED procedural sedation (EDPS) for PEC differ from those requiring EDPS for other procedures:they are at higher risk of adverse events, and require fewer drugs and lower doses. We attempt to verify this using an EDPS registry at a Canadian, tertiary care teaching hospital. METHODS:This is a retrospective review of patients that underwent EDPS for the period of June 2006 to September 2014. We compared demographics, medication use and intra-procedural adverse events between those receiving EDPS for PEC for AF compared to that for other indications. We report the asssociation between AEs and predictors using logistic regression. RESULTS:A total of 4867 patients were included, 714 for PEC for AF and 4153 for other indications. PEC patients were more likely male (58.5％vs. 47.1％), older (59.5 years vs. 48.1 years), and less likely to be ASA I (46.6％ vs. 69.0％). PEC patients received smaller doses of propofol and less likely to receive adjuvant analgesic therapy (11.5％ vs. 78.2％). PEC patients were more likely to experience hypotension (27.6％vs. 16.5％) but respiratory AEs (apnea, hypoxia and airway intervention) were not different. CONCLUSION:EDPS for PEC differs from that conducted for other purposes:patients tend to be less healthy, receive smaller doses of medication and more likely to suffer hypotension without an increase in respiratory AEs. These factors should be considered when performing EDPS.

BACKGROUND:This prospective, randomized trial was undertaken to evaluate the utility of adding end-tidal capnometry (ETC) to pulse oximetry (PO) in patients undergoing procedural sedation and analgesia (PSA) in the emergency department (ED). METHODS:The patients were randomized to monitoring with or without ETC in addition to the current standard of care. Primary endpoints included respiratory adverse events, with secondary endpoints of level of sedation, hypotension, other PSA-related adverse events and patient satisfaction. RESULTS:Of 986 patients, 501 were randomized to usual care and 485 to additional ETC monitoring. In this series, 48％ of the patients were female, with a mean age of 46 years. Orthopedic manipulations (71％), cardioversion (12％) and abscess incision and drainage (12％) were the most common procedures, and propofol and fentanyl were the sedative/analgesic combination used for most patients. There was no difference in patients experiencing de-saturation (SaO2<90％) between the two groups; however, patients in the ETC group were more likely to require airway repositioning (12.9％ vs. 9.3％,P=0.003). Hypotension (SBP<100 mmHg or <85 mmHg if baseline <100 mmHg) was observed in 16 (3.3％) patients in the ETC group and 7 (1.4％) in the control group (P=0.048). CONCLUSIONS:The addition of ETC does not appear to change any clinically significant outcomes. We found an increased incidence of the use of airway repositioning maneuvers and hypotension in cases where ETC was used. We do not believe that ETC should be recommended as a standard of care for the monitoring of patients undergoing PSA.