Brian Grunau

Comparing the prognosis of those with initial shockable and non-shockable rhythms with increasing durations of CPR: Informing minimum durations of resuscitation

AIM There is little data to inform the appropriate duration of resuscitation attempts for out-of-hospital cardiac arrest (OHCA). We assessed the relationship of elapsed duration since commencement of resuscitation and outcomes, highlighting differences between initial shockable and non-shockable rhythms. METHODS We examined consecutive adult non-traumatic EMS-treated OHCA in a single health region. We plotted the time-dependent accrual of patients with ROSC, as well as dynamic estimates of outcomes as a function of duration from commencement of professional resuscitation, and compared subgroups dichotomized by initial rhythm. Logistic regression tested the association between time-to-ROSC and outcomes. RESULTS Of 1627 adult EMS-treated cases of OHCA, 1617 patients were included; 14% survivors and 10% with favorable neurological outcomes. Time-to-ROSC (per minute increase) was independently associated with survival in those with initial shockable (aOR 0.95, 95% CI 0.92-0.97) and non-shockable (aOR 0.83; 95% CI 0.78-0.88) rhythms. Similar associations were seen with favorable neurologic outcome. The elapsed duration at which the probability of survival fell below 1% was 48 and 15 min in the shockable and non-shockable groups, respectively. Median time-to-termination of resuscitation was 36 and 26 min in the shockable and non-shockable groups, respectively. CONCLUSION The subgroup of initial shockable rhythms showed a less pronounced association of time-to-ROSC with outcomes, and demonstrated higher resilience for neurologically intact survival after prolonged periods of resuscitation. This data can guide minimum durations of resuscitation, however should not be considered as evidence for termination of resuscitation as survival in this cohort may have been improved with longer resuscitation attempts.

Association Between Duration of Resuscitation and Favorable Outcome After Out-of-Hospital Cardiac Arrest: Implications for Prolonging or Terminating Resuscitation.

Background: Little evidence guides the appropriate duration of resuscitation in out-of-hospital cardiac arrest, and case features justifying longer or shorter durations are ill defined. We estimated the impact of resuscitation duration on the probability of favorable functional outcome in out-of-hospital cardiac arrest using a large, multicenter cohort. Methods: This was a secondary analysis of a North American, single-blind, multicenter, cluster-randomized, clinical trial (ROC-PRIMED [Resuscitation Outcomes Consortium Prehospital Resuscitation Using an Impedance Valve and Early Versus Delayed]) of consecutive adults with nontraumatic, emergency medical services–treated out-of-hospital cardiac arrest. Primary exposure was duration of resuscitation in minutes (onset of professional resuscitation to return of spontaneous circulation [ROSC] or termination of resuscitation). Primary outcome was survival to hospital discharge with favorable outcome (modified Rankin scale [mRS] score of 0–3). Subjects were additionally classified as survival with unfavorable outcome (mRS score of 4–5), ROSC without survival (mRS score of 6), or without ROSC. Subject accrual was plotted as a function of resuscitation duration, and the dynamic probability of favorable outcome at discharge was estimated for the whole cohort and subgroups. Adjusted logistic regression models tested the association between resuscitation duration and survival with favorable outcome. Results: The primary cohort included 11 368 subjects (median age, 69 years [interquartile range, 56–81 years]; 7121 men [62.6%]). Of these, 4023 (35.4%) achieved ROSC, 1232 (10.8%) survived to hospital discharge, and 905 (8.0%) had an mRS score of 0 to 3 at discharge. Distribution of cardiopulmonary resuscitation duration differed by outcome (P<0.00001). For cardiopulmonary resuscitation duration up to 37.0 minutes (95% confidence interval, 34.9–40.9 minutes), 99% with an eventual mRS score of 0 to 3 at discharge achieved ROSC. The dynamic probability of an mRS score of 0 to 3 at discharge declined over elapsed resuscitation duration, but subjects with initial shockable cardiac rhythm, witnessed cardiac arrest, and bystander cardiopulmonary resuscitation were more likely to survive with favorable outcome after prolonged efforts (30–40 minutes). After adjustment for prehospital (odds ratio, 0.93; 95% confidence interval, 0.92–0.95) and inpatient (odds ratio, 0.97; 95% confidence interval, 0.95–0.99) covariates, resuscitation duration was associated with survival to discharge with an mRS score of 0 to 3. Conclusions: Shorter resuscitation duration was associated with likelihood of favorable outcome at hospital discharge. Subjects with favorable case features were more likely to survive prolonged resuscitation up to 47 minutes. Clinical Trial Registration: URL: http://clinicaltrials.gov. Unique identifier: NCT00394706.

Association between hospital post-resuscitative performance and clinical outcomes after out-of-hospital cardiac arrest

BACKGROUND Survival varies among those resuscitated from out-of-hospital cardiac arrest (OHCA). Evidence-based performance measures have been used to describe hospital quality of care in conditions such as acute coronary syndrome and major trauma. It remains unclear if adherence to performance measures is associated with better outcome in patients hospitalized after OHCA. OBJECTIVES To assess whether a composite performance score based on evidence-based guidelines for care of patients resuscitated from OHCA was independently associated with clinical outcomes. METHODS Included were 3252 patients with OHCA who received care at 111 U.S. and Canadian hospitals participating in the Resuscitation Outcomes Consortium (ROC-PRIMED) study between June 2007 and October 2009. We calculated composite performance scores for all patients, aggregated these at the hospital level, then associated them with patient mortality and favorable neurological status at discharge. RESULTS Composite performance scores varied widely (median [IQR] scores from lowest to highest hospital quartiles, 21% [20%, 25%] vs. 59% [55%, 64%]. Adjusted survival to discharge increased with each quartile of performance score (from lowest to highest: 16.2%, 20.8%, 28.5%, 34.8%, P<0.01), with similar findings for adjusted rates of good neurologic status. Hospital score was significantly associated with outcome after risk adjustment for established baseline factors (highest vs. lowest adherence quartile: adjusted OR of survival 1.64; 95% CI 1.13, 2.38). CONCLUSIONS Greater survival and favorable neurologic status at discharge were associated with greater adherence to recommended hospital based post-resuscitative care guidelines. Consideration should be given to measuring, reporting and improving hospital adherence to guideline-based performance measures, which could improve outcomes following OHCA.

Relationship between Time-to-ROSC and Survival in Out-of-hospital Cardiac Arrest ECPR Candidates: When is the Best Time to Consider Transport to Hospital?

Abstract Objective: Extracorporeal cardiopulmonary resuscitation (ECPR) may improve outcomes for refractory out-of-hospital cardiac arrest (OHCA). Transport of intra-arrest patients to hospital however, may decrease CPR quality, potentially reducing survival for those who would have achieved return-of-spontaneous-circulation (ROSC) with further on-scene resuscitation. We examined time-to-ROSC and patient outcomes for the optimal time to consider transport. Methods: From a prospective registry of consecutive adult non-traumatic OHCAs, we identified a hypothetical ECPR-eligible cohort of EMS-treated patients with age ≤ 65, witnessed arrest, and bystander CPR or EMS arrival < 10 minutes. We assessed the relationship between time-to-ROSC and survival, and constructed a ROC curve to illustrate the ability of a pulseless state to predict non-survival with conventional resuscitation. Results: Of 6,571 EMS-treated cases, 1,206 were included with 27% surviving. Increasing time–to–ROSC (per minute) was negatively associated with survival (adjusted OR 0.91; 95%CI 0.89–0.93%). The yield of survivors per minute of resuscitation increased from commencement and started to decline in the 8th minute. Fifty percent and 90% of survivors had achieved ROSC by 8.0 and 24 min, respectively, at which times the probability of survival for those with initial shockable rhythms was 31% and 10%, and for non-shockable rhythms was 5.2% and 1.6%. The ROC curve illustrated that the 16th minute of resuscitation maximized sensitivity and specificity (AUC = 0.87, 95% CI 0.85–0.89). Conclusion: Transport for ECPR should be considered between 8 to 24 minutes of professional on-scene resuscitation, with 16 minutes balancing the risks and benefits of early and later transport. Earlier transport within this window may be preferred if high quality CPR can be maintained during transport and for those with initial non-shockable rhythms.

Post-resuscitation arterial oxygen and carbon dioxide and outcomes after out-of-hospital cardiac arrest

OBJECTIVE To determine if arterial oxygen and carbon dioxide abnormalities in the first 24h after return of spontaneous circulation (ROSC) are associated with increased mortality in adult out-of-hospital cardiac arrest (OHCA). METHODS We used data from the Resuscitation Outcomes Consortium (ROC), including adult OHCA with sustained ROSC ≥1h after Emergency Department arrival and at least one arterial blood gas (ABG) measurement. Among ABGs measured during the first 24h of hospitalization, we identified the presence of hyperoxemia (PaO2≥300mmHg), hypoxemia (PaO2<60mmHg), hypercarbia (PaCO2>50mmHg) and hypocarbia (PaCO2<30mmHg). We evaluated the associations between oxygen and carbon dioxide abnormalities and hospital mortality, adjusting for confounders. RESULTS Among 9186 OHCA included in the analysis, hospital mortality was 67.3%. Hyperoxemia, hypoxemia, hypercarbia, and hypocarbia occurred in 26.5%, 19.0%, 51.0% and 30.6%, respectively. Initial hyperoxemia only was not associated with hospital mortality (adjusted OR 1.10; 95% CI: 0.97-1.26). However, final and any hyperoxemia (1.25; 1.11-1.41) were associated with increased hospital mortality. Initial (1.58; 1.30-1.92), final (3.06; 2.42-3.86) and any (1.76; 1.54-2.02) hypoxemia (PaO2<60mmHg) were associated with increased hospital mortality. Initial (1.89; 1.70-2.10); final (2.57; 2.18-3.04) and any (1.85; 1.67-2.05) hypercarbia (PaCO2>50mmHg) were associated with increased hospital mortality. Initial (1.13; 0.90-1.41), final (1.19; 1.04-1.37) and any (1.01; 0.91-1.12) hypocarbia (PaCO2<30mmHg) were not associated with hospital mortality. CONCLUSIONS In the first 24h after ROSC, abnormal post-arrest oxygen and carbon dioxide tensions are associated with increased out of-hospital cardiac arrest mortality.

Dantrolene for the treatment of MDMA toxicity.

MDMA (3,4-methylenedioxymethamphetamine), popularly known as “Ecstasy,” was first introduced and patented by Merck & Co., Inc., in 1914 as an appetite suppressant. Currently, its primary role is as an illegal stimulant used to produce a euphoric effect during parties. This case report de scribes a 31-year-old man who, after taking 3 tablets of Ecstasy, presented to an emergency department with a decreased level of consciousness and became progressively hyperthermic and rigid. During the course of his acute illness, his temperature reached 42.2°C rectally. He was given mechanical ventilation. He was aggressively cooled and dantrolene was initiated. Soon after the administration of dantrolene his temperature decreased and his rigidity began to resolve. The only complication was rhabdomyolysis with a creatine kinase level increasing to over 150 μkat/L. This did not progress to acute renal failure. The patient made a full recovery and was discharged to psychiatry for assessment.

Safety and efficiency of outpatient versus emergency department-based coronary CT angiography for evaluation of patients with potential ischemic chest pain☆

BACKGROUND While coronary CT angiography (coronary CTA) may be comparable to standard care in diagnosing acute coronary syndrome (ACS) in emergency department (ED) chest pain patients, it has traditionally been obtained prior to ED discharge and a strategy of delayed outpatient coronary CTA following an ED visit has not been evaluated. OBJECTIVE To investigate the safety of discharging stable ED patients and obtaining outpatient CCTA. METHODS At two urban Canadian EDs, patients up to 65 years with chest pain but no findings indicating presence of ACS were further evaluated depending upon time of presentation: (1) ED-based coronary CTA during normal working hours, (2) or outpatient coronary CTA within 72 hours at other times. All data were collected prospectively. The primary outcome was the proportion of patients who had an outpatient coronary CTA ordered and had a predefined major adverse cardiac event (MACE) between ED discharge and outpatient CT; secondary outcome was the ED length of stay in both groups. RESULTS From July 1, 2012 to June 30, 2014, we enrolled 521 consecutive patients: 350 with outpatient CT and 171 with ED-based CT. Demographics and risk factors were similar in both cohorts. No outpatient CT patients had a MACE prior to coronary CTA. (0.0%, 95% CI 0 to 0.9%) The median length of stay for ED-based evaluation was 6.6 hours (interquartile range 5.4 to 8.3 hours) while the outpatient group had a median length of stay of 7.0 hours (IQR 6.0 to 9.8 hours, n.s.). CONCLUSIONS In ED chest pain patients with a low risk of ACS, performing coronary CTA as an outpatient may be a safe strategy.

An interesting presentation of pediatric tetanus.

Despite successful large-scale immunization programs in North America, there remains a significant population without active immunity to tetanus toxins because immunizations have been refused or delayed, and because of waning immunity. We report the case of a 7-year-old boy who presented to the emergency department with a chin laceration and a 7-day history of repeated falls of increasing frequency. We found this case to be associated with dysphagia and facial spasm, and we learned that the child had dropped a brick on his foot 2 weeks previously. The patient was subsequently diagnosed with tetanus and treated accordingly. Tetanus presentations to emergency departments may vary from mild muscular rigidity to advanced respiratory failure and thus clinicians should consider the diagnosis in various clinical presentations, especially in areas remote from advanced supportive care.

Safety of a Brief Emergency Department Observation Protocol for Patients With Presumed Fentanyl Overdose

Study objective: Fentanyl overdoses are increasing and few data guide emergency department (ED) management. We evaluate the safety of an ED protocol for patients with presumed fentanyl overdose. Methods: At an urban ED, we used administrative data and explicit chart review to identify and describe consecutive patients with uncomplicated presumed fentanyl overdose (no concurrent acute medical issues) from September to December 2016. We linked regional ED and provincial vital statistics databases to ascertain admissions, revisits, and mortality. Primary outcome was a composite of admission and death within 24 hours. Other outcomes included treatment with additional ED naloxone, development of a new medical issue while in the ED, and length of stay. A prespecified subgroup analysis assessed low‐risk patients with normal triage vital signs. Results: There were 1,009 uncomplicated presumed fentanyl overdose, mainly by injection. Median age was 34 years, 85% were men, and 82% received out‐of‐hospital naloxone. One patient was hospitalized and one discharged patient died within 24 hours (combined outcome 0.2%; 95% confidence interval [CI] 0.04% to 0.8%). Sixteen patients received additional ED naloxone (1.6%; 95% CI 1.0% to 2.6%), none developed a new medical issue (0%; 95% CI 0% to 0.5%), and median length of stay was 173 minutes (interquartile range 101 to 267). For 752 low‐risk patients, no patients were admitted or developed a new issue, and one died postdischarge; 3 (0.4%; 95% CI 0.01% to 1.3%) received ED naloxone. Conclusion: In our cohort of ED patients with uncomplicated presumed fentanyl overdose—typically after injection—deterioration, admission, mortality, and postdischarge complications appear low; the majority can be discharged after brief observation. Patients with normal triage vital signs are unlikely to require ED naloxone.

Prevalence, natural history, and time-dependent outcomes of a multi-center North American cohort of out-of-hospital cardiac arrest extracorporeal CPR candidates

AIM Estimate prevalence of ECPR-eligible subjects in a large, North American, multi-center cohort, describe natural history with conventional resuscitation, and predict optimal timing of transition to ECPR. METHODS Secondary analysis of clinical trial enrolling adults with non-traumatic OHCA. Primary outcome was survival to discharge with favorable outcome (mRS 0-3). Subjects were additionally classified as survival with unfavorable outcome (mRS 4-5), ROSC without survival (mRS 6), or without ROSC. We plotted subject accrual as a function of resuscitation duration (CPR onset to return of spontaneous circulation (ROSC) or termination of resuscitation), and estimated time-dependent probabilities of ROSC and mRS 0-3 at discharge. Adjusted logistic regression models tested the association between resuscitation duration and survival with mRS 0-3. RESULTS Of 11,368 subjects, 1237 (10.9%; 95%CI 10.3-11.5%) were eligible for ECPR, Of these, 778 (63%) achieved ROSC, 466 (38%) survived to discharge, and 377 (30%) had mRS 0-3 at discharge. Half with eventual mRS 0-3 achieved ROSC within 8.8min (95%CI 8.3-9.2min) of resuscitation, and 90% within 21.0min (95%CI 19.1-23.7min). Time-dependent probabilities of ROSC and mRS 0-3 declined over elapsed resuscitation, and the likelihood of additional cases with mRS 0-3 beyond 20min was 8.4% (95%CI 5.9-11.0%). Resuscitation duration was independently associated with survival to discharge with mRS 0-3 (OR 0.95; 95%CI 0.92-0.97). CONCLUSION Approximately 11% of subjects were eligible for ECPR. Only one-third survived to discharge with favorable outcome. Performing 9-21min of conventional resuscitation captured most ECPR-eligible subjects with eventual mRS 0-3 at hospital discharge.