Michael Olinger

Standard cardiopulmonary resuscitation versus active compression-decompression cardiopulmonary resuscitation with augmentation of negative intrathoracic pressure for out-of-hospital cardiac arrest: a randomised trial

BACKGROUND Active compression-decompression cardiopulmonary resuscitation (CPR) with decreased intrathoracic pressure in the decompression phase can lead to improved haemodynamics compared with standard CPR. We aimed to assess effectiveness and safety of this intervention on survival with favourable neurological function after out-of-hospital cardiac arrest. METHODS In our randomised trial of 46 emergency medical service agencies (serving 2·3 million people) in urban, suburban, and rural areas of the USA, we assessed outcomes for patients with out-of-hospital cardiac arrest according to Utstein guidelines. We provisionally enrolled patients to receive standard CPR or active compression-decompression CPR with augmented negative intrathoracic pressure (via an impedance-threshold device) with a computer-generated block randomisation weekly schedule in a one-to-one ratio. Adults (presumed age or age ≥18 years) who had a non-traumatic arrest of presumed cardiac cause and met initial and final selection criteria received designated CPR and were included in the final analyses. The primary endpoint was survival to hospital discharge with favourable neurological function (modified Rankin scale score of ≤3). All investigators apart from initial rescuers were masked to treatment group assignment. This trial is registered with ClinicalTrials.gov, number NCT00189423. FINDINGS 2470 provisionally enrolled patients were randomly allocated to treatment groups. 813 (68%) of 1201 patients assigned to the standard CPR group (controls) and 840 (66%) of 1269 assigned to intervention CPR received designated CPR and were included in the final analyses. 47 (6%) of 813 controls survived to hospital discharge with favourable neurological function compared with 75 (9%) of 840 patients in the intervention group (odds ratio 1·58, 95% CI 1·07-2·36; p=0·019]. 74 (9%) of 840 patients survived to 1 year in the intervention group compared with 48 (6%) of 813 controls (p=0·03), with equivalent cognitive skills, disability ratings, and emotional-psychological statuses in both groups. The overall major adverse event rate did not differ between groups, but more patients had pulmonary oedema in the intervention group (94 [11%] of 840) than did controls (62 [7%] of 813; p=0·015). INTERPRETATION On the basis of our findings showing increased effectiveness and generalisability of the study intervention, active compression-decompression CPR with augmentation of negative intrathoracic pressure should be considered as an alternative to standard CPR to increase long-term survival after cardiac arrest. FUNDING US National Institutes of Health grant R44-HL065851-03, Advanced Circulatory Systems.

Prehospital Oral Endotracheal Intubation by Rural Basic Emergency Medical Technicians

STUDY OBJECTIVE To determine whether basic emergency medical technicians (EMT-B) can perform prehospital oral endotracheal intubation with success rates comparable to those of paramedics. METHODS This was a nonrandomized, controlled trial using historical controls. Seven basic life support emergency medical services systems in six counties and their corresponding emergency departments in rural Indiana participated. Eighty-seven full-time EMTs with no prior or concurrent paramedic training volunteered for intubation training. Apneic prehospital patients aged 16 years or older without an active gag reflex or massive facial trauma were eligible for intubation and study enrollment. The EMTs completed a 9-hour didactic and airway manikin training course in direct laryngoscopic endotracheal intubation. The course was adapted from the national paramedic curriculum. RESULTS Thirty-four (39%) of the EMT-Bs attempted to intubate 57 eligible patients. In 49.1% of these patients, successful endotracheal tube placement was confirmed by the receiving physician (95% confidence interval, 36.4% to 61.9%); in contrast, the prehospital intubation success rates from three previous studies of manikin-trained paramedics ranged from 76.9% to 90.6% (P < .001). Complications included five (9%) inadvertent extubations, two endotracheal tube cuff ruptures, two prolonged intubation attempts, and one mainstem bronchus intubation. There were no unrecognized esophageal intubations. Two of the seven EMS agencies did not report any intubation data. CONCLUSION Rural EMTs with didactic and airway manikin training failed to achieve prehospital intubation success rates comparable to those of paramedic controls. Possible explanations include training deficiencies, poor skill transference from manikin to human intubation, infrequent intubation experiences, and inconsistent supervision.

Treatment of non-traumatic out-of-hospital cardiac arrest with active compression decompression cardiopulmonary resuscitation plus an impedance threshold device

BACKGROUND A recent out-of-hospital cardiac arrest (OHCA) clinical trial showed improved survival to hospital discharge (HD) with favorable neurologic function for patients with cardiac arrest of cardiac origin treated with active compression decompression cardiopulmonary resuscitation (CPR) plus an impedance threshold device (ACD+ICD) versus standard (S) CPR. The current analysis examined whether treatment with ACD+ITD is more effective than standard (S-CPR) for all cardiac arrests of non-traumatic origin, regardless of the etiology. METHODS This is a secondary analysis of data from a randomized, prospective, multicenter, intention-to-treat, OHCA clinical trial. Adults with presumed non-traumatic cardiac arrest were enrolled and followed for one year post arrest. The primary endpoint was survival to hospital discharge (HD) with favorable neurologic function (Modified Rankin Scale score ≤ 3). RESULTS Between October 2005 and July 2009, 2738 patients were enrolled (S-CPR=1335; ACD+ITD=1403). Survival to HD with favorable neurologic function was greater with ACD+ITD compared with S-CPR: 7.9% versus 5.7%, (OR 1.42, 95% CI 1.04, 1.95, p=0.027). One-year survival was also greater: 7.9% versus 5.7%, (OR 1.43, 95% CI 1.04, 1.96, p=0.026). Nearly all survivors in both groups had returned to their baseline neurological function by one year. Major adverse event rates were similar between groups. CONCLUSIONS Treatment of out-of-hospital non-traumatic cardiac arrest patients with ACD+ITD resulted in a significant increase in survival to hospital discharge with favorable neurological function when compared with S-CPR. A significant increase survival rates was observed up to one year after arrest in subjects treated with ACD+ITD, regardless of the etiology of the cardiac arrest.

PREHOSPITAL PEARLS, PITFALLS, AND UPDATES

The rapid proliferation of emergency medical services in the United States has led to numerous controversies concerning delivery, interventions, and efficacy. This article presents a brief overview of the important literature in this expanding field. Important clinical topics, including first-responder defibrillation, rapid sequence intubation, and airway management, are reviewed. In addition, several important medicolegal topics pertaining to pre-hospital care are analyzed.

Emergency Resuscitation of Patients Enrolled in the US Diaspirin Cross-linked Hemoglobin (DCLHb) Clinical Efficacy Trial

INTRODUCTION Optimal emergent management of traumatic hemorrhagic shock patients requires a better understanding of treatment provided in the prehospital/Emergency Medical Services (EMS) and emergency department (ED) settings. Hypothesis/Problem Described in this research are the initial clinical status, airway management, fluid and blood infusions, and time course of severely-injured hemorrhagic shock patients in the EMS and ED settings from the diaspirin cross-linked hemoglobin (DCLHb) clinical trial. METHODS Data were analyzed from 17 US trauma centers gathered during a randomized, controlled, single-blinded efficacy trial of a hemoglobin solution (DCLHb) as add-on therapy versus standard therapy. RESULTS Among the 98 randomized patients, the mean EMS Glasgow Coma Scale (GCS) was 10.6 (SD = 5.0), the mean EMS revised trauma score (RTS) was 6.3 (SD = 1.9), and the mean injury severity score (ISS) was 31 (SD = 17). Upon arrival to the ED, the GCS was 20% lower (7.8 (SD = 5.3) vs 9.7 (SD = 6.3)) and the RTS was 12% lower (5.3 (SD = 2.0) vs 6.0 (SD = 2.1)) than EMS values in blunt trauma patients (P < .001). By ED disposition, 80% of patients (78/98) were intubated. Rapid sequence intubation (RSI) was utilized in 77% (60/78), most often utilizing succinylcholine (65%) and midazolam (50%). The mean crystalloid volume infused was 4.2 L (SD = 3.4 L), 80% of which was infused within the ED. Emergency department blood transfusion occurred in 62% of patients, with an average transfused volume of 1.2 L (SD = 2.0 L). Blunt trauma patients received 2.1 times more total fluids (7.4 L vs 3.5 L, < .001) and 2.4 times more blood (2.4 L vs 1.0 L, P < .001). The mean time of patients taken from injury site to operating room (OR) was 113 minutes (SD = 87 minutes). Twenty-one (30%) of the 70 patients taken to the OR from the ED were sent within 60 minutes of the estimated injury time. Penetrating trauma patients were taken to the OR 52% sooner than blunt trauma patients (72 minutes vs 149 minutes, P < .001). CONCLUSION Both GCS and RTS decreased prior to ED arrival in blunt trauma patients. Intubation was performed using RSI, and crystalloid infusion of three times the estimated blood loss volume (L) and blood transfusion of the estimated blood loss volume (L) were provided in the EMS and ED settings. Surgical intervention for these trauma patients most often occurred more than one hour from the time of injury. Penetrating trauma patients received surgical intervention more rapidly than those with a blunt trauma mechanism.

Milestones in treatment: the tipping point and the ResQ Trial

www.thelancet.com Vol 377 June 18, 2011 2081 converting-enzyme inhibitors, or angiotensin-receptor blockers. All of these analyses showed that belimumab 10 mg/kg remained superior to standard therapy alone (table). The proportions of patients entering BLISS-52 with renal disease were 18–21% as measured by SELENASLEDAI and 12–17% on the basis of British Isles Lupus Assessment Group A/B organ domain scores, with 7–9% having a proteinuria concentration of 2 g or more per 24 h. The comment by Neeraj Dhaun and David C Kluth that the proportion of patients with proteinuria of 2 g or more per 24 h increased to 14–18% (on the basis of data in table 3 of the original article) is not correct. The safety data presented in table 3 represent the incidence of any adverse event or the worst laboratory abnormality (reported in any of 13 assessments) that occurred at any point during the course of the study. The proportion of patients at week 52 with proteinuria of 2 g or more per 24 h actually decreased from baseline to 4·2% and 5·5% in the belimumab 10 mg/kg and 1 mg/kg groups, respectively, versus 7·6% with standard therapy alone; a 2-grade shift in proteinuria from baseline to week 52 was noted across all treat ment groups (table). Additionally, there was a trend towards greater reductions in proteinuria, creatinine, and renal fl are rate over 52 weeks in the belimumab 10 mg/kg group. GlaxoSmithKline and Human Genome Sciences have committed to running a phase 2/3 study of belimumab in patients with lupus nephritis to assess this important population properly.

The association of health status and providing consent to continued participation in an out-of-hospital cardiac arrest trial performed under exception from informed consent

OBJECTIVES Emergency medical research performed under federal regulation 21 § CFR 50.24 provides a means to protect human subjects and investigate novel time-sensitive treatments. Although prospective individual consent is not required for studies conducted under this regulation, consent from a legally authorized representative (LAR) or the patient at the earliest feasible opportunity is required to obtain short- and long-term outcome data. The objective of this study was to determine which demographic, cardiac arrest, and patient outcome characteristics predicted the likelihood of obtaining informed consent following enrollment under exception from informed consent in a multicenter cardiac arrest study. METHODS This investigation was an analysis of data collected during a multisite, randomized, controlled, out-of-hospital cardiac arrest clinical trial performed under 21 § CFR 50.24. Research personnel attempted to obtain informed consent from LARs and subjects for medical records review of primary outcome data, as well as consent for neurologic outcome assessments up to 1 year post-cardiac arrest. Hospital discharge and neurologic status were obtained from public records and/or medical records up until the time consent was formally denied, in accordance with federal regulations and guidance. Local institutional review boards also allowed medical records review for cases where consent was neither obtained nor declined despite multiple consent attempts. Patient demographic, cardiac arrest, and clinical outcome characteristics were analyzed in univariate multinomial regression models, with consent status (obtained, denied, neither obtained nor denied) as the dependent variable. A multivariate multinomial logistic regression was then performed. An exploratory secondary analysis following the same process was performed after assigning patients who neither consented nor declined to the declined consent group. RESULTS Among a total study population of 1,655 cardiac arrest subjects, 457 were transported and had consent attempted (27.6%). The survival status and neurologic function at the time of hospital discharge were known in 440 of 457 (96%) subjects. In the multivariate analysis, initial rhythm of ventricular fibrillation/ventricular tachycardia (VF/VT) and survival with good neurologic outcome were strong predictors of obtaining consent (odds ratio [OR] = 3.15, 95% confidence interval [CI] = 1.73 to 5.75; OR = 7.64, 95% CI = 2.28 to 25.63, respectively). The exploratory secondary analysis also showed initial rhythm of VF/VT and survival with good neurologic outcome as strong predictors of obtaining consent (OR = 1.86, 95% CI = 1.17 to 2.95; OR = 4.52, 95% CI = 2.21 to 9.26, respectively). CONCLUSIONS Initial arrest rhythm and survival with good neurologic outcome were highly predictive of obtaining consent in this cardiac arrest trial. This phenomenon could result in underrepresentation of outcome data in the study arm with the worse outcome and represents a significant potential confounder in studies performed under 21 § CFR 50.24. Future revisions to the exception from informed consent regulations should allow access to critical survival data recorded as part of standard documentation, regardless of patient consent status.