Remote ischemic preconditioning (rIPC), induced by cycles of transient limb ischemia and reperfusion (IR), is cardioprotective. The optimal rIPC-algorithm is not established. We investigated the ...effect of cycle numbers and ischemia duration within each rIPC-cycle and the influence of effector organ mass on the efficacy of cardioprotection. Furthermore, the duration of the early phase of protection by rIPC was investigated. Using a tourniquet tightened at the inguinal level, we subjected C57Bl/6NTac mice to intermittent hind-limb ischemia and reperfusion. The rIPC-protocols consisted of (I) two, four, six or eight cycles, (II) 2, 5 or 10 min of ischemia in each cycle, (III) single or two hind-limb occlusions and (IV) 0.5, 1.5, 2.0 or 2.5 h intervals from rIPC to index cardiac ischemia. All rIPC algorithms were followed by 5 min of reperfusion. The hearts were subsequently exposed to 25 min of global ischemia and 60 min of reperfusion in an ex vivo Langendorff model. Cardioprotection was evaluated by infarct size and post-ischemic hemodynamic recovery. Four to six rIPC cycles yielded significant cardioprotection with no further protection by eight cycles. Ischemic cycles lasting 2 min offered the same protection as cycles of 5 min ischemia, whereas prolonged cycles lasting 10 min abrogated protection. One and two hind-limb preconditioning were equally protective. In our mouse model, the duration of protection by rIPC was 1.5 h. These findings indicate that the number and duration of cycles rather than the tissue mass exposed to rIPC determines the efficacy of rIPC.
Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) has been reported in individual studies to significantly increase the rate of bystander CPR and survival from cardiac arrest.
We undertook a ...systematic review and meta-analysis to evaluate the impact of DA-CPR programs on key clinical outcomes following out-of-hospital cardiac arrest. We searched the PubMED, EMBASE, CINAHL, ERIC and Cochrane Central Register of Controlled Trials databases from inception until July 2018. Eligible studies compared systems with and without dispatcher-assisted CPR programs. The results of included studies were classified into 3 categories for the purposes of more accurate analysis: comparison of outcomes in systems with DA-CPR programs, case-based comparison of DA-CPR to bystander CPR, and case-based comparisons of DA-CPR to no CPR before EMS arrival. The GRADE system was used to assess certainty of evidence at an outcome level. We used random-effects models to produce summary effect sizes across all outcomes.
Of 5531 citations screened, 33 studies were eligible for inclusion. All included studies were observational. Evidence certainty across all outcomes was assessed as low or very low. In system-level and patient-level comparisons, the provision of DA-CPR compared with no DA-CPR was consistently associated with improved outcome across all analyses. Comparison of DA-CPR to bystander CPR produced conflicting results. Findings were consistent across sensitivity analyses and the pediatric sub-group.
These results support the recommendation that dispatchers provide CPR instructions to callers for adults and children with suspected OHCA.
Review registration: PROSPERO- CRD42018091427.
Previous trials have suggested that vasopressin and methylprednisolone administered during in-hospital cardiac arrest might improve outcomes.
To determine whether the combination of vasopressin and ...methylprednisolone administered during in-hospital cardiac arrest improves return of spontaneous circulation.
Multicenter, randomized, double-blind, placebo-controlled trial conducted at 10 hospitals in Denmark. A total of 512 adult patients with in-hospital cardiac arrest were included between October 15, 2018, and January 21, 2021. The last 90-day follow-up was on April 21, 2021.
Patients were randomized to receive a combination of vasopressin and methylprednisolone (n = 245) or placebo (n = 267). The first dose of vasopressin (20 IU) and methylprednisolone (40 mg), or corresponding placebo, was administered after the first dose of epinephrine. Additional doses of vasopressin or corresponding placebo were administered after each additional dose of epinephrine for a maximum of 4 doses.
The primary outcome was return of spontaneous circulation. Secondary outcomes included survival and favorable neurologic outcome at 30 days (Cerebral Performance Category score of 1 or 2).
Among 512 patients who were randomized, 501 met all inclusion and no exclusion criteria and were included in the analysis (mean SD age, 71 13 years; 322 men 64%). One hundred of 237 patients (42%) in the vasopressin and methylprednisolone group and 86 of 264 patients (33%) in the placebo group achieved return of spontaneous circulation (risk ratio, 1.30 95% CI, 1.03-1.63; risk difference, 9.6% 95% CI, 1.1%-18.0%; P = .03). At 30 days, 23 patients (9.7%) in the intervention group and 31 patients (12%) in the placebo group were alive (risk ratio, 0.83 95% CI, 0.50-1.37; risk difference: -2.0% 95% CI, -7.5% to 3.5%; P = .48). A favorable neurologic outcome was observed in 18 patients (7.6%) in the intervention group and 20 patients (7.6%) in the placebo group at 30 days (risk ratio, 1.00 95% CI, 0.55-1.83; risk difference, 0.0% 95% CI, -4.7% to 4.9%; P > .99). In patients with return of spontaneous circulation, hyperglycemia occurred in 77 (77%) in the intervention group and 63 (73%) in the placebo group. Hypernatremia occurred in 28 (28%) and 27 (31%), in the intervention and placebo groups, respectively.
Among patients with in-hospital cardiac arrest, administration of vasopressin and methylprednisolone, compared with placebo, significantly increased the likelihood of return of spontaneous circulation. However, there is uncertainty whether this treatment results in benefit or harm for long-term survival.
ClinicalTrials.gov Identifier: NCT03640949.
Augmented mortality and morbidity following an acute myocardial infarction in patients with diabetes mellitus Type 2 (T2DM) may be caused by increased sensitivity to ischemia reperfusion (IR) injury ...or altered activation of endogenous cardioprotective pathways modified by T2DM per se or ischemic preconditioning (IPC). We aimed to investigate, whether the duration of T2DM influences sensitivity against IR injury and the efficacy of IPC, and how myocardial glucose oxidation rate was involved. Male Zucker diabetic fatty rats (homozygote (fa/fa)) at ages 6-(prediabetic), 12- (onset diabetes) and 24-weeks of age (late diabetes) and their age-matched non-diabetic controls (heterozygote (fa/+) were subjected to IR injury in the Langendorff model and randomised to IPC stimulus or control. T2DM rats were endogenously protected at onset of diabetes, as infarct size was lower in 12-weeks T2DM animals than in 6- (35±2% vs 53±4%; P = 0.006) and 24-weeks animals (35±2% vs 72±4%; P<0.0001). IPC reduced infarct size in all groups irrespective of the presence of T2DM and its duration (32±3%; 20±2%; 36±4% respectively; (ANOVA P<0.0001). Compared to prediabetic rats, myocardial glucose oxidation rates were reduced during stabilisation and early reperfusion at onset of T2DM, but these animals retained the ability to increase oxidation rate in late reperfusion. Late diabetic rats had low glucose oxidation rates throughout stabilisation and reperfusion. Despite inherent differences in sensitivity to IR injury, the cardioprotective effect of IPC was preserved in our animal model of pre-, early and late stage T2DM and associated with adaptations to myocardial glucose oxidation capacity.
Utstein-style reporting templates provide a structured framework with which to compare systems of care for cardiac arrest. The 2004 Utstein reporting template encompassed both out-of-hospital and ...in-hospital cardiac arrest. A 2015 update of the Utstein template focused on out-of-hospital cardiac arrest, which makes this update of the in-hospital template timely. Representatives of the International Liaison Committee on Resuscitation developed an updated in-hospital Utstein reporting template iteratively by meeting face-to-face, by teleconference, and by online surveys between 2013 and 2018. Data elements were grouped by hospital factors, patient variables, pre-event factors, cardiac arrest and postresuscitation processes, and outcomes. Elements were classified as core or supplemental by use of a modified Delphi process. Variables were described as core if they were considered essential. Core variables should enable reasonable comparisons between systems and are considered essential for quality improvement programs. Together with core variables, supplementary variables are considered useful for research.
Background Thiamine supplementation has demonstrated protective effects in a mouse model of cardiac arrest. The aim of this study was to investigate the neuroprotective effects of thiamine in a ...clinically relevant large animal cardiac arrest model. The hypothesis was that thiamine reduces neurological injury evaluated by neuron-specific enolase levels. Methods and Results Pigs underwent myocardial infarction and subsequently 9 minutes of untreated cardiac arrest. Twenty minutes after successful resuscitation, the pigs were randomized to treatment with either thiamine or placebo. All pigs underwent 40 hours of intensive care and were awakened for assessment of functional neurological outcome up until 9 days after cardiac arrest. Nine pigs were included in both groups, with 8 in each group surviving the entire intensive care phase. Mean area under the curve for neuron-specific enolase was similar between groups, with 81.5 μg/L per hour (SD, 20.4) in the thiamine group and 80.5 μg/L per hour (SD, 18.3) in the placebo group, with an absolute difference of 1.0 (95% CI, -57.8 to 59.8;
=0.97). Likewise, there were no absolute difference in neurological deficit score at the end of the protocol (2 95% CI, -38 to 42;
=0.93). There was no absolute mean group difference in lactate during the intensive care period (1.1 mmol/L 95% CI, -0.5 to 2.7;
=0.16). Conclusions In this randomized, blinded, placebo-controlled trial using a pig cardiac arrest model with myocardial infarction and long intensive care and observation for 9 days, thiamine showed no effect in changes to functional neurological outcome or serum levels of neuron-specific enolase. Thiamine treatment had no effect on lactate levels after successful resuscitation.
Defibrillation is essential for achieving return of spontaneous circulation (ROSC) following out-of-hospital cardiac arrest (OHCA) with shockable rhythms. This study aimed to investigate if the type ...of defibrillator used was associated with ROSC in OHCA.
This study included adult patients with OHCA from the Danish Cardiac Arrest Registry from 2016 to 2021 with at least 1 defibrillation by the emergency medical services. We used multivariable logistic regression and a difference-in-difference analysis, including all patients with or without emergency medical services shock to assess the causal inference of using the different defibrillator models (LIFEPAK or ZOLL) for OHCA defibrillation. Among 6516 patients, 77% were male, the median age (quartile 1; quartile 3) was 70 (59; 79), and 57% achieved ROSC. In total, 5514 patients (85%) were defibrillated using LIFEPAK (ROSC: 56%) and 1002 patients (15%) were defibrillated using ZOLL (ROSC: 63%). Patients defibrillated using ZOLL had an increased adjusted odds ratio (aOR) for ROSC compared with LIFEPAK (aOR, 1.22 95% CI, 1.04-1.43). There was no significant difference in 30-day mortality (aOR, 1.11 95% CI, 0.95-1.30). Patients without emergency medical services defibrillation, but treated by ZOLL-equipped emergency medical services, had a nonsignificant aOR for ROSC compared with LIFEPAK (aOR, 1.10 95% CI, 0.99-1.23) and the difference-in-difference analysis was not statistically significant (OR, 1.10 95% CI, 0.91-1.34).
Defibrillation using ZOLL X Series was associated with increased odds for ROSC compared with defibrillation using LIFEPAK 15 for patients with OHCA. However, a difference-in-difference analysis suggested that other factors may be responsible for the observed association.
ObjectivesThe COVID-19 pandemic forced hospital organisation and healthcare professionals to prepare for large quantities of patients in isolation rooms. In situ simulation may seem promising in ...order to manage the organisational changes that the pandemic require. This study aims to investigate in situ simulations influence on healthcare professional’s self-perceived preparedness to face the pandemic.DesignA qualitative focus group study.SettingWe conducted full scale in situ simulations over a 3-week period in April 2020, including 277 healthcare professionals, at a Danish University Hospital. Subsequently, six semistructured focus group interviews, including 22 participants from the simulations, were conducted in May 2020.Participants22 healthcare professionals participated in the focus group interviews.MethodsThe simulations consisted of a briefing, two scenarios focusing on acute respiratory insufficiency and correct use of personal protective equipment (PPE), and a debriefing. We conducted six focus group interviews using comparable semistructured interview guides focusing on the organisational restructuring of the departments and outcomes of the needs-driven simulation-based programme. We used thematic analysis to identify main themes.ResultsThe informants perceived that the simulations resulted in positive experiences for the healthcare professionals and perceived the organisational changes as effective. They highlighted that simulation enhanced teamwork, demystified the COVID-19 disease, and improved skills, in correct use of PPE and acute treatment of COVID-19 patients. Data revealed that a predefined simulation task force including both experienced simulators and medical experts for facilitation of in situ simulation would be beneficial.ConclusionIn situ simulation may be useful to enhance learning on organisation and individual level during a pandemic. This educational activity could serve an important role in facilitating hospital preparation and education of large numbers of healthcare professionals during a healthcare crisis. Introduction of a simulation task force is suggested to handle coordination and rapid enrolment across the hospital.
Fast arrival of the cardiac arrest team (CAT) is associated with improved survival after in-hospital cardiac arrest however little is known about how we can minimize delays in CAT arrival. This study ...aimed to investigate differences in the cardiac arrest call procedures in Danish hospitals and identify causes for adverse events delaying the CAT arrival.
This nationwide study surveyed all public somatic hospitals in Denmark with a CAT. We searched for all patient safety incidences related to the cardiac arrest call procedure during a two-year period. Two researchers reviewed all incidents and categorized the cause as either human, technical, or not possible to classify, and whether the incident caused a delay of the CAT arrival.
In total, 36 hospitals (78%) responded and all hospitals used a telephone number, a CAT activation button or both for activation of the CAT. We found 131 reports describing an event related to activation of the CAT of which 87 incidents (66%) caused a definite delay in CAT arrival. The most common were human errors (43%) followed by technical errors (32%) and errors not possible to classify (25%). Almost half of the incidents (47%) could have been avoided if the hospitals used a CAT activation button with direct activation of the CAT.
There are major differences on the in-hospital cardiac arrest call procedure in Danish hospitals. Human errors are the most frequent cause of safety incidents and may be avoided by simplifying the cardiac arrest call procedure with CAT activation buttons.
Errors during treatment may affect patient outcomes and can include errors in treatment algorithms, teamwork, and system errors. In-hospital cardiac arrests (IHCA) require immediate and effective ...treatment, and delays are known to reduce survival. In-situ simulation is a tool that can be used to study emergency responses, including IHCA. We investigated system errors discovered during unannounced in-situ simulated IHCA.
This multicenter cohort study included unannounced, full-scale IHCA in-situ simulations followed by a debriefing based on PEARLS with plus-delta used in the analysis phase. Simulations and debriefings were video-recorded for subsequent analysis. System errors observed were categorized by thematic analysis and analyzed for clinical implications. Errors related to treatment algorithm and clinical performance were excluded.
We conducted 36 in-situ simulations across 4 hospitals with a total discovery of 30 system errors. On average, we discovered 0.8 system errors per simulation within the categories: human, organizational, hardware, or software errors. Of these, 25 errors (83%) had direct treatment consequences. System errors caused treatment delays in 15 cases, a need for alternative actions in 6 cases, omission of actions in 4 cases, and other consequences in 5 cases.
Using unannounced in-situ simulations, we identified almost one system error per simulation, and most of these errors were deemed to impact treatment negatively. The errors affected treatment by either causing delays, need for alternative treatment options, or omitting treatment actions. We suggest that hospitals focus on the need for regular testing of the emergency response by conducting full-scale unannounced in-situ simulations. This should be a priority to improve patient safety and care.