Course Of Resuscitation Research Articles

Early intravenous hydrocortisone in sepsis: A randomized control trial (Protocol)

Background: The evidence of the appropriate timing of hydrocortisone is still weak and controversial. Observational studies showed a trend towards greater benefits when hydrocortisone was given earlier in the course of septic shock resuscitation. This study evaluates the effects of early intravenous low-dose hydrocortisone administered at the beginning of the onset of sepsis-induced hypotension compared with standard care. Methods: This study is a single-center, parallel-group, double-blinded, randomized control trial, conducted in a non-trauma emergency department. Adult patients with sepsis-induced hypotension will be included. Patients will be randomly assigned in a 1:1 ratio to receive early intravenous low-dose hydrocortisone or standard care. Blood inflammatory biomarkers at baseline will be collected. The primary outcome is 28-day mortality. Resuscitation-related secondary outcomes and safety outcomes will also be observed. Outcomes will be compared between groups. Subgroup analyses considering inflammatory biomarker levels will also be performed to evaluate the effect of early intravenous hydrocortisone, especially in patients with hyperinflammation. Hypothesis: We hypothesize that early intravenous low-dose hydrocortisone administration in patients with sepsis-induced hypotension would result in less mortality and improve resuscitation outcomes, especially in subgroup of patients with hyperinflammation. Ethics and dissemination: The study protocol was approved by the Siriraj Institutional Review Board with the certificate of approval number Si 917/2023. Trial registration: Clinicaltrial.gov NCT06217939

Metrics of impulsiveness of manual chest compressions for out-of-hospital cardiopulmonary resuscitation

AimPropose new metrics of impulsiveness of manual chest compressions (CCs) that account for shape and duration, separate the characteristics of the compressive part of the CC cycle from those of the recoil part, and are uncorrelated to CC depth and rate. MethodsWe conducted a retrospective analysis of adult out-of-hospital cardiac arrest monitor-defibrillator recordings having CPR data. Specifically, episodes of adult patients with ≥ 1000 compressions free of leaning were examined. CCs were obtained from the depth signal of the valid episodes, and we calculated the novel metrics: compression area index (CAI), recoil area index (RAI), compression impulsiveness index (CII) and recoil impulsiveness index (RII). Generalized linear mixed-effects models and Jonckheere-Terpstra trend analyses were employed to measure differences between populations and trends, and the absolute value of Pearson's correlation coefficient |r| was used to report dependence between variables. Statistics are reported as median and interquartile range. ResultsWe analyzed 982,340 CCs corresponding to 453 episodes, for which we calculated their CAI, RAI and duty cycle (DC). We analyzed the metrics for various populations: age, sex, any ROSC achieved and disposition, and found that CAI was significantly different according to patient disposition and RAI relative to age and sex (p<0.05). None of the metrics was correlated strongly to depth or rate (|r| values of 0.22 or smaller), and all of them varied for CC series corresponding to the same rescuer over the course of resuscitation (ptrend<0.05). However, we observed that the metrics are not balanced, in that for any value of DC, CAI and RAI span almost their entire ranges. ConclusionThe proposed metrics correctly and completely describe manual CC waveforms, improve upon the DC, since they depend on the signal waveform, and provide additional information to current indicators of quality CPR, depth and rate. Furthermore, they allow to differentiate the compressive and recoil parts of the CC cycle, reflecting influence of the rescuer (via CAI or CII) and of the biomechanics of the patient's chest (via RAI or RII). Thus, they have the potential to contribute to better understanding CPR dynamics and, eventually, to enhanced quality of CPR practice as additional indicators of proper manual CC technique.

Neonatal resuscitation virtual training course: Use of an educational platform by medical students at a public university in Peru

IntroductionSatisfactory performance in Neonatal Resuscitation requires continuous training, and several technologies can enhance its scope. This study was carried out to evaluate the use of an educational platform by medical students in a Neonatal Resuscitation virtual course. Materials and methodsDescriptive study with the data available on the Neonatal Resuscitation virtual course platform, evaluating the use of a population corresponding to the total number of undergraduate Medicine students from the Universidad Nacional Mayor de San Marcos (UNMSM) who enrolled as students to take the Paediatrics course in the last year of their studies during the years 2018 and 2019 in Lima, Peru. ResultsData from 379 sixth-year medical students in the 2018-I, 2019-I, and 2019-II semesters were included. Students entered the virtual course an average of 23 days before taking their online exam, and the average theory review time in the virtual system was 120 min. Students with outstanding performance in their scores completed 2 virtual exams, but there was no difference in the other characteristics. ConclusionsThe sequence developed in the Neonatal Resuscitation virtual course, which begins with "learn, see, and practice", offers a greater capacity to retain the knowledge and skills acquired. The virtual offer of the theoretical component of Neonatal Resuscitation allows the use of innovative tools that make it possible to achieve a high performance of medical students when completing the virtual course of Neonatal Resuscitation.

Use of the expanded Apgar score for the assessment of intraventricular and intraparenchymal haemorrhage risk in neonates.

Preterm birth is a key factor contributing to haemorrhage incidence in neonates. This study focused on defining relevant parameters for the assessment of intraventricular and intraparenchymal haemorrhage risks in neonates. Chi-square automatic interaction detection was used to analyse the Apgar score (AS), the Apgar max score, and the course of resuscitation documented according to the expanded AS in 696 infants born between 2009 and 2011 in the Neonatal and Intensive Care Department of the Medical University of Warsaw. Gestational age was the most relevant discriminating variable for the prediction of intraventricular III degree and intraparenchymal haemorrhage incidences. Infants born before the 31st week of pregnancy made up 80% of the intraventricular or intraparenchymal haemorrhage cases. Additionally, a fraction of inspired oxygen > 0.8 at ten minutes after birth was a better discriminating variable in the youngest neonates than an Apgar max score ≤ 5, identifying 31.6% and 20.6% of infants with intraventricular and intraparenchymal haemorrhage, respectively. Consideration of the oxygen concentration supplied during resuscitation significantly improves the prognosis of intraventricular and intraparenchymal haemorrhages in preemies compared to the use of the classical AS.

Limiting calcium overload after cardiac arrest: The role of human albumin in controlled automated reperfusion of the whole body.

Regarding the overall inadequate results after cardiopulmonary resuscitation, the development of new treatment concepts is urgently needed. Controlled Automated Reperfusion of the whoLe body (CARL) represents a therapy bundle to control the conditions of reperfusion and the composition of the reperfusate after cardiac arrest (CA). The aim of this study was to investigate the plasma expander's role in the CARL priming solution and examine its mechanism of action. Viscosity, osmolality, colloid osmotic pressure (COP), pH and calcium binding of different priming solutions were measured in vitro and compared to in vivo data. N = 16 pigs were allocated to receive CARL following 20 min of untreated CA with either human albumin 20% (HA, N = 8) or gelatin polysuccinate 4% (GP, N = 8). Blood gas analyses were performed during the first hour of reperfusion and catecholamine and fluid requirements were recorded. Neurological outcome was assessed by neurological deficit scoring (NDS) on the seventh day. In vitro, addition of HA to the CARL priming solution resulted in higher COP and higher calcium-binding than GP. In vivo, treatment with HA led to greater reduction of ionized calcium and higher extracorporeal flows within the first 30 min of reperfusion with no difference in catecholamine support and fluid requirement. Seven-day survival of 75% with no difference in NDS was observed in both groups. Our data show that the plasma expander in the CARL priming solution has a significant effect on the initial reperfusate and can potentially influence the course of resuscitation. However, seven-day survival and NDS did not differ between groups.

Abstract 13048: A Simple Model to Describe the Relationship Between Compression Force and Depth During CPR

Aim: The relationship between force and depth during manual chest compressions depends on the patient and on the dynamics with which the rescuer applies the force. Force-depth models with many fitting parameters have been proposed making physical interpretation complicated. The aim of this work was to design a simpler force-depth model, accommodating anticipated differences in compression and recoil phases. Materials and Methods: Force and acceleration signals were extracted from out-of-hospital-cardiac arrest (OHCA) defibrillator recordings (TVF&amp;R, OR, USA), equipped with CPR technology. Compression depth and velocity signals were computed from acceleration. We analyzed intervals of 20-s within the 1st min of chest compressions. Our model decomposes the applied force as the sum of an elastic and a damped term, considering different damping coefficients for the compression and recoil phases. Coefficient of elasticity was calculated at the instant of maximum compression depth (null velocity) and damping coefficients at the instants of maximum compression and recoil velocities. The estimated depth signal is shown in the figure. The goodness of the model was assessed through the determination coefficient R 2 . Results: We analyzed 1,074 compressions from 30 OHCA recordings. Median (IQR) compression depth was 4.6 (4.0-5.4) cm; compression rate was 107 (102–113) cpm; coefficient of elasticity was 100.67 (78.95–125.01) N/cm; compression damping coefficient was 2.57 (1.84–3.29) N/(cm/s) and recoil damping coefficient was 3.59 (2.58–4.90) N/(cm/s). Median R 2 was 0.993 (0.984–0.996). Conclusions: This model, derived using fewer parameters, could help with the interpretation of the mechanical properties of the chest during CPR. It may also be useful for the assessment of inter-patient differences with age, sex, and body constitution, as well as of the evolution of elasticity and damping of patient’s chest during the course of resuscitation.

Impact of Early, Low-Dose Factor VIIa on Subsequent Transfusions and Length of Stay in Cardiac Surgery

Recombinant factor VII (rFVIIa) is used to treat cardiac surgical bleeding in an off-label manner. However, optimal dosing and timing of administration to provide efficacious yet safe outcomes remain unknown. Retrospective, observational study. Tertiary care academic center. Cardiac surgical patients (N = 214) who received low-dose rFVIIa for cardiac surgical bleeding. Patients were allocated into one of three groups based on timing of rFVIIa administration during the course of bleeding resuscitation based on the number of hemostatic products given before rFVIIa administration: group one = ≤one products (n = 82); group two = two-to-four products (n = 73); and group three= ≥five products (n = 59). Patients who received low-dose rFVIIa later in the course of bleeding resuscitation (group three) had longer intensive care unit stays (p = 0.014) and increased incidence of postoperative renal failure when compared with group one (p = 0.039). Total transfusions were lowest in patients who received rFVIIa early in the course of resuscitation (group one) (median, two [interquartile range (IQR), 1-4.75]) and highest in group three (median, 11 [IQR, 8-14]; p < 0.001). Subsequent blood product transfusions after rFVIIa administration were highest in group two (p = 0.003); however, the median for all three groups was two products. There were no differences in thrombosis, reexplorations, or mortality in any of the groups. This study identified no differences in adverse outcomes based on timing of administration of low-dose rFVIIa for cardiac surgical bleeding defined by stage of resuscitation, but the benefits of early administration remain unclear.

A COMPARISON OF MOUTH-TO-MOUTH, MOUTH-TO-POCKET FACE MASK AND BAG VALVE MASK VENTILATION DURING LIFEGUARDS’ CPR: A MANIKIN STUDY

Aim: To compare the effectiveness of ventilation of each of three methods: mouth-to-mouth ventilation using a foil face mask with a filter pad, mouth-to-mask technique with a pocket face mask and bag valve mask ventilation using a self-inflating bag and a face mask, performed during CPR by qualified non-medical rescuers. Material and methods: Ventilation effectiveness was assessed on manikin and compared for mouth-to-mouth, mouth-to-mask and bag valve mask ventilation method. 46 qualified non-medical rescuers-lifeguards participated in the study. Tidal Volume of 0,4-0,7L was considered as effective. The length of chest compressions pauses was recorded. The ventilation methods were also evaluated subjectively by participants in the questionnaire. Results: Effectiveness 90,75% vs. 92,38% vs. 69,5%; average number of effective rescue breaths: 7,26 vs. 7,39 vs. 5,65; average length of chest compressions pause: 7,7s vs. 8,1s vs. 9,9s for MTM, MPFM and BMV respectively. MPFM method was considered as the easiest, the second in terms of the difficulty in use was MTM, and BMV was described as the most difficult to use. Conclusions: Artificial ventilation using the pocket mask, in the course of resuscitation performed by one qualified non-medical rescuer, e.g. the water lifeguard, is an effective method ensuring adequate tidal volume and is more effective than mouth-to-mouth method and bag valve mask ventilation.

Abstract 253: Trajectory of Ventricular Fibrillation Prognostic Status During Cardiopulmonary Resuscitation

Background: Resuscitation from out-of-hospital cardiac arrest (OHCA) due to ventricular fibrillation (VF) typically involves continuous CPR cycles interrupted every 2 minutes for rhythm analysis and potential defibrillation. Quantitative measures of the VF ECG waveform have been proposed to guide therapy for VF arrest because they are associated with myocardial energetics, are dynamic over the course of resuscitation, and predict outcome. However, while VF waveform measures have until recently have required CPR interruption to accurately gauge prognostic status, CPR interruptions are associated with a lower chance of survival. We used a novel waveform measure previously-validated during active CPR to estimate the course of VF status through the 2-minute CPR cycle between consecutive shocks. Methods: We conducted an observational study of patients with VF OHCA who experienced recurrent VF for at least 90 seconds following initial shock. We used the continuous defibrillator ECG to calculate the VF waveform measure as a function of predicted probability of survival-with-intact-neurologic-status at 1-s intervals over the course of resuscitation between shocks. Results: We collected 499 VF ECG segments (≥90 seconds) during CPR from 313 patients. The trajectory of the average prognostic VF measure had a 3-phase time-dependent pattern (Fig. 1). During CPR, the slope of the measure decreased during the initial 25 s of VF (slope = -12%/min) and was relatively flat during the subsequent 65-s interval of VF (slope = +1%/min). Furthermore, slope decreased sharply following the cessation of CPR for rhythm analysis, charge, and shock (slope = -23%/min). Conclusion: On average, a novel VF waveform measure assessed during the scheduled cycle of CPR and rhythm analysis between consecutive shocks was characterized by a period of decline, stabilization, and then decline. Whether these changes in VF status can be used to improve care for individual patients is uncertain.

Assessment of dynamic changes in cardiac function during resuscitation of patients with suspected septic shock: A prospective, observational, cohort study.

To describe changes in cardiac function throughout the course of resuscitation of patients with suspected septic shock. Prospective observational cohort study of Point-of-Care Transthoracic Echocardiograms (TTE) obtained in Emergency Department (ED) patients with a presumed infectious cause of hypotension within one hour of initiating IV fluid resuscitation. Findings of this pre-resuscitation TTE were compared to mid-resuscitation TTE (obtained upon disposition from the ED), and post-resuscitation TTE (obtained after admission to hospital). 22 enrolled patients had a second TTE available for comparison to the initial, pre-resuscitation TTE. 12 patients had a mid-resuscitation TTE and 16 patients had a post-resuscitation TTE. We observed a high incidence of changes on TTE during the clinical course of resuscitation (14/22 [64%]). Patients who developed LV or RV dysfunction during resuscitation were more likely to require vasopressor infusion and ICU admission (Spearman's coefficients [95% CI] of 0.68 [0.36-0.86] and 0.47 [0.04;0.75] respectively). Development of RV dysfunction alone was associated with increased use of positive pressure ventilation and vasopressor infusion (Spearman's coefficients [95% CI] of 0.43 [0;0.72] and 0.47 [0.05,0.75] respectively). Cardiac function changes assessed by TTE are common during the resuscitation of patients with septic shock. These changes likely reflect the underlying physiology of patients with septic shock and correlate with need for interventions and higher level of care. Further work is required to characterize these changes and to elucidate how to use these physiologic data to guide management.

Factors affecting the course of resuscitation from cardiac arrest with pulseless electrical activity in children and adolescents

BackgroundAlthough in-hospital pediatric cardiac arrests and cardiopulmonary resuscitation occur >15,000/year in the US, few studies have assessed which factors affect the course of resuscitation in these patients. We investigated transitions from Pulseless Electrical Activity (PEA) to Ventricular Fibrillation/pulseless Ventricular Tachycardia (VF/pVT), Return of Spontaneous Circulation (ROSC) and recurrences from ROSC to PEA in children and adolescents with in-hospital cardiac arrest. MethodsEpisodes of cardiac arrest at the Children's Hospital of Philadelphia were prospectively registered. Defibrillators that recorded chest compression depth/rate and ventilation rate were applied. CPR variables, patient characteristics and etiology, and dynamic factors (e.g. the proportion of time spent in PEA or ROSC) were entered as time-varying covariates for the transition intensities under study. ResultsIn 67 episodes of CPR in 59 patients (median age 15 years) with cardiac arrest, there were 52 transitions from PEA to ROSC, 22 transitions from PEA to VF/pVT, and 23 recurrences of PEA from ROSC. Except for a nearly significant effect of mean compression depth beyond a threshold of 5.7 cm, only dynamic factors that evolved during CPR favored a transition from PEA to ROSC. The latter included a lower proportion of PEA over the last 5 min and a higher proportion of ROSC over the last 5 min. Factors associated with PEA to VF/pVT development were age, weight, the proportion spent in VF/pVT or PEA the last 5 min, and the general transition intensity, while PEA recurrence from ROSC only depended on the general transition intensity. ConclusionThe clinical course during pediatric cardiac arrest was mainly influenced by dynamic factors associated with time in PEA and ROSC. Transitions from PEA to ROSC seemed to be favored by deeper compressions.

Abstract 343: Chest Compression Compliance With Guidelines Declines Over the Course of Rescues

Introduction: CPR guidelines recommend limits for rate and depth, and release (avoidance of leaning). Simultaneous compliance with all three recommendations is challenging, sustained compliance more so. Hypothesis: Compliance with rate, depth and release guidelines is limited, and will decline over the course of rescues. Methods: Acceleration and force signals were extracted from monitor/defibrillators equipped with CPR monitors in 248 adult cases of manual CPR during out-of-hospital resuscitations treated by Tualatin Valley Fire &amp; Rescue (TVF&amp;R, Tigard, OR) during 2016 and 2017. TVF&amp;R personnel delivered continuous compression CPR with real-time feedback available for rate, depth and leaning. Depth was calculated from acceleration. Peak depth, release force, and rate were measured for each compression. Release with force exceeding 2.5 kg-f was counted as incomplete (leaning). Results: Cases included 1802 (1055-2683) (median, IQR) compressions (total 481,407 compressions). Compliance with all three recommendations was 25% initially, declining to 19% for the ends of the longest rescues (&gt; 3000 compressions from 48 cases). Depth compliance and complete release varied relatively little (31-36%, 93-95% respectively) and irregularly over the course of resuscitation. Early, 45% of compressions were too shallow (&lt; 50 mm), and 21% were too deep (&gt; 60 mm). Depth exceptions shifted over the course of resuscitation (to 36%, 28% respectively). Rate compliance declined from 73% to 54%. Rates below 100 cpm were 9% initially, declining to 5%. Rates exceeding 120 cpm were 18% early on, but climbed to 41% towards the end of long resuscitations, accounting for most of the decline in compliance with guidelines. Conclusions: Compliance with all 3 recommendations for CPR compressions is challenging, and becomes more so as the chest changes in response to compressions. Most problematic is a steady increase in compression rates above 120 cpm.

Abstract 284: Cerebral Oximetry During Resuscitation: Course and Outcome

Background: Anoxic brain injury is a common cause of death following out-of-hospital cardiac arrest (OHCA). Cerebral oximetry provides a real-time tool to brain ischemia. Little is known about the course of cerebral oximetry and its relationship to outcome following OHCA. Methods: We conducted a pilot cohort study during OHCA to evaluate the course and prognosis related to cerebral oximetry in a single US EMS agency. Cerebral oximetry was applied by first responders at the outset of EMS resuscitation using the Nonin SenSmart Model X-100 Universal Oximetry System. EMS providers were blinded to oximeter information. The oximeter recording was linked to the defibrillator recording and the OHCA clinical registry, which includes the outcomes of return of spontaneous circulation (ROSC) and survival to hospital discharge with good function as determined by Cerebral Performance Category (CPC) of 1 or 2. We evaluated the variability of cerebral oximetry over time and the relationship between oximetry and outcome according to ROSC and survival status. Results: Of the 100 eligible OHCA events, 81 had complete oximeter and defibrillator information. Average age was 62, 43% were female, 14% presented with ventricular fibrillation, 49% (n=40) achieved ROSC, and 16% (n=13) survived (all with CPC of 1 or 2). Average initial cerebral oxygen saturation was 46% (SD 15) among all cases and among those requiring resuscitation &gt;10 minutes. Among those with ongoing resuscitation, mean oximetry was 49% at 5 minutes and 51% at 10 minutes. The average change in oximetry during resuscitation was 8% with 59% demonstrating an increase in oximetry, 32% a decrease, and 9% no change. Brain oximetry increased 10% following ROSC. Initial cerebral oximetry was 53% (SD 18) among survivors versus 44% (SD 15) among non-survivors (p=0.1). When stratified by groups defined by ROSC and survival, initial brain oximetry was 43% among those without ROSC, 46% among those who achieved ROSC but did not survive, and 53% among those who survived (p=0.1 test for trend). Conclusion: Cerebral oximetry can be deployed by first responders in OHCA. Cerebral oximetry exhibits some variability during the course of resuscitation and increases with ROSC. Whether cerebral oximetry can be used to guide care is uncertain.

Abstract 436: Ventilation Rate Impact on End-Tidal Carbon Dioxide Levels During Manual Cardiopulmonary Resuscitation

Introduction: End-tidal carbon dioxide (ETCO2) levels during cardiopulmonary resuscitation (CPR) depend primarily on the blood flow generated by chest compressions, on the ventilation rate and on the metabolic activity of the patient tissues. A better characterization of the influence of each factor is warranted. Objective: To assess the quantitative relation between ETCO2 and ventilation rate from retrospective analysis of adult out-of-hospital resuscitations. Methods: Monitor recordings of 163 adult out-of-hospital cardiac arrest cases treated by Tualatin Valley Fire &amp; Rescue (Tigard, OR) from 2012 through 2017. Recordings contained concurrent capnogram, ECG, transthoracic impedance (TI) and compression depth. Episodes were manually inspected to identify pairs of segments with different ventilation rates ( vr 1, vr 2) and meeting the following criteria: 1) Reliable capnogram to annotate the ETCO2 value of each segment ( ET 1, ET 2). 2) A maximum of 2 min separation between segments so that similar metabolic activity could be assumed. 3) Absence of circulation, by inspecting the ECG and the TI signal. 4) Compression depth and rate variation between segments &lt; 4 mm and 8 compressions per minute, respectively. We applied curve fitting to the data with a custom equation (see figure) and non-linear least squares as fit option. Results: Forty pairs of segments were included. The figure shows the measurements and the resulting fitting curve normalized to vr 1 = 10 ventilations per minute (vpm). Factor K was 0.93, and the coefficient of determination R 2 was 0.90. Thus, for instance, the ETCO2 at 5 vpm would be 1.64 times the ETCO2 at 10 vpm. Similarly, the ETCO2 at 15 vpm would be 0.80 times the ETCO2 at 10 vpm. Conclusions: The obtained curve may help to eliminate the influence of ventilation rate on ETCO2 during cardiopulmonary resuscitation. This finding is a step forward to a better understanding of ETCO2 variation during the course of resuscitation.

Chest compression release velocity factors during out-of-hospital cardiac resuscitation

BackgroundHigher chest compression release velocity (CCRV) has been associated with better outcomes after out-of-hospital cardiac arrest (OHCA), and patient factors have been associated with variations in chest wall compliance and compressibility. We evaluated whether patient sex, age, weight, and time in resuscitation were associated with CCRV during pre-hospital resuscitation from OHCA. MethodsObservational study of prospectively collected OHCA quality improvement data in two suburban EMS agencies in Arizona between 10/1/2008 and 12/31/2016. Subject-level mean CCRV during the first 10 min of compressions was correlated with categorical variables by the Wilcoxon rank-sum test and with continuous variables by the Spearman’s rank correlation coefficient. Generalized estimating equation and linear mixed-effect models were used to study the trend of CCRV over time. ResultsDuring the study period, 2535 adult OHCA cases were treated. After exclusion criteria, 1140 cases remained for analysis. Median duration of recorded compressions was 8.70 min during the first 10 min of CPR. An overall decline in CCRV was observed even after adjusting for compression depth. The subject-level mean CCRV was higher for minutes 0–5 than for minutes 5–10 (mean 347.9 mm/s vs. 339.0 mm/s, 95% CI of the difference −12.4 to −5.4, p < 0.0001). Males exhibited a greater mean CCRV compared to females [344.4 mm/s (IQR 307.3–384.6) vs. 331.5 mm/s (IQR 285.3–385.5), p = 0.013]. Mean CCRV was negatively correlated with age and positively correlated with patient weight. ConclusionCCRV declines significantly over the course of resuscitation. Patient characteristics including male sex, younger age, and increased weight were associated with a higher CCRV.

Changing the management of refractory ventricular fibrillation: The consideration of earlier utilization of dual sequential defibrillation

Dual Sequential Defibrillation (DSD) has shown promise in the management of refractory ventricular fibrillation (RVF). In the recent past, there have been a number of reports on the topic with varying results. Some studies have concluded that DSD provides no benefit over standard defibrillation therapy of RVF in terms of survival and neurological outcome. In fact, termination of RVF and achieving return of spontaneous circulation (ROSC) are achieved quite frequently in patients with DSD. Unfortunately, DSD has been utilized very late in the course of resuscitation, likely masking a great deal of its potential benefit. Interventions at this later phase of resuscitation are much less likely to produce a beneficial outcome, regardless of their ability to impact the course of events. It is suggested that earlier use of DSD can potentially improve ROSC, ultimate survival, and neurological outcome. After a review of the existing literature on the topic, we will propose that DSD be considered for use at a much earlier time in the resuscitation of patients with RVF. In addition to the consideration of its use in resuscitation, clinicians and device manufacturers must also address the impact on the two defibrillation devices employed in DSD due to the potential for damage and resultant defibrillator dysfunction.

Comparison of 7 and 11–12 French Access for REBOA: Results from the AAST Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) Registry

Background: The introduction of low-profile devices designed for resuscitative endovascular balloon occlusion of the aorta (REBOA) after trauma has the potential to change practice, outcomes, and complication profiles.Methods: The AAST Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry was used to identify REBOA patients from 16 centers. Presentation, intervention, and outcome variables were compared via traditional 11–12 French access platforms and trauma-specific devices requiring only 7 French access.Results: From November 2013 to December 2017, 242 patients with complete data were identified, constituting 124 7 French and 118 11–12 French uses. Demographics of presentation were not diff erent between the two groups, except that patients using the 7 French had a higher mean Injury Severity Score (39.2 vs. 34.1, p = 0.028). The 7 French was associated with a lower cut-down requirement for access (22.6% vs. 37.3%, p = 0.049) and increased ultrasound guidance utilization (29.0% vs. 23.7%, p = 0.049). The 7 French afforded earlier aortic occlusion in the course of resuscitation (median 25.0 mins vs. 30 mins, p = 0.010) and a lower median requirement of packed red blood cells (10.0 vs. 15.5 units, p = 0.006) and fresh frozen plasma (7.5 vs. 14.0 units, p = 0.005). The 7 French patients were more likely to survive 24 h (58.1% vs. 42.4%, p = 0.015) and less likely to suff er in-hospital mortality (57.3% vs. 75.4%, p = 0.003). Finally, the 7 French device was associated with a four times lower rate of distal extremity embolism (20.0% vs. 5.6%, p = 0.014; OR 95% CI 4.25 [1.25–14.45]) compared to the 11–12 French. Conclusions: The introduction of trauma-specific 7 French REBOA devices appears to have infl uenced REBOA practices, with earlier use in severely injured hypotensive patients via less invasive means that are associated with lower transfusion requirements, fewer thrombotic complications, and improved survival. Additional study is required to determine optimal REBOA use.

Abstract 316: Cardiac Arrest Rhythm Transitions in Drug Overdose-Related Resuscitation

Introduction: The prehospital electrocardiogram (ECG) may inform treatment of out-of-hospital cardiac arrest (OHCA) patients regardless of etiology. While drug overdose (OD)-OHCA is increasingly common, little is known about the characteristics and utility of the intra-resuscitation OD-OHCA ECG signal. In this study, we sought to investigate the evolving ECG rhythm state of OD-OHCA patients to identify potentially informative patterns or phenomena. Methods: Case data, including electronic defibrillator files, for emergency medical services treated OD-OHCA were obtained from the Resuscitation Outcomes Consortium, a multi-site clinical research network in the US and Canada. OD-OHCA case status was previously established by site-level data abstractors reviewing prehospital and in-hospital electronic medical records for evidence of drug involvement. Continuous ECG traces were extracted and chest compression-free ECG segments were parsed with custom MATLAB (vR2017a) software. Each ECG segment was manually rhythm-classified by a research specialist. Rhythm transitions were identified as changes in rhythm between sequential analyzable rhythm segments. Transitions were tabulated and summarized by their rhythms and timing. Results: Complete prehospital ECG data were available for 130 patients, comprising 1,112 ECG segments of which 771 (69.3%) were analyzable. The mean (SD) age was 33.6 (11.3) years and 68.3% were male. The most commonly observed rhythm at the segment level was low amplitude (“fine”) ventricular fibrillation (VF), accounting for 44.1% of all segments, although at the case level asystole was the most common rhythm, present in 47.7% of all cases. We recorded 292 rhythm transitions, with a mean (SD) 2.5 (1.5) transitions per case. Mean (SD) time to first transition was 11.1 (6.9) minutes and mean (SD) time to last transition was 19.8(8.8) minutes. The most frequently observed transition was from asystole to low amplitude ventricular fibrillation (17.1%). Conclusions: The OD-OHCA ECG is varied and dynamic, presenting in numerous rhythms and transitioning between rhythms throughout the course of resuscitation.

Abstract 110: The Dynamic Clinical Course of Resuscitation in Children With Cardiac Arrest

Background: During cardiac arrest, a child may be in one of five clinical states (“rhythms”): 1) Bradycardia with poor perfusion; 2) Pulseless Electrical Activity (PEA); 3) Ventricular Fibrillation or Pulseless Ventricular Tachycardia (VF/VT); 4) Asystole; or 5) Spontaneous Circulation (ROSC). The aim of study was to investigate and quantify the dynamic characteristics of this process. Methods: We prospectively acquired data on rhythm and clinical states using recording defibrillators during active CPR. Recordings were analyzed as a multi-state statistical model, focusing on transitions between PEA (including bradycardia with poor perfusion), VF/VT, Asystole, and ROSC (defined as an organized electrical rhythm without chest compressions &gt;= 1 minute). Instantaneous transition rates were obtained by smoothing the Nelson-Aalen estimator of cumulative intensities. Results: In 74 Cardiac Arrest events with evaluable data, median patient age was 15 years [range 1.75 to 22.9; IQR 11 to 17]. Fifty percent had a respiratory etiology and 51 % were female. PEA was the most frequent presenting cardiac arrest rhythm (38 %); followed by VF/VT (24 %), bradycardia (22 %), and asystole (16 %). Starting from time of defibrillator attachment (median 3 minutes into the event) as shown in the figure that shows 45 minutes of CPR, the prevalence of sustained ROSC reached an asymptotic value of 30 % at 20 minutes. We observed a temporary surge of PEA at about 12 minutes, resulting from a doubling (from 0.1 to 0.2 transitions/min) of the instantaneous transition rate of ROSC to PEA during this period. Conclusion: We provide a quantitative overview of the dynamic process of clinical state transitions during in-hospital cardiac arrest and resuscitation in older children and adolescents. A notable feature was a temporary increase in the prevalence of PEA at 12 minutes.

Indications for fluid resuscitation in patients with septic shock: Post-hoc analyses of the CLASSIC trial.

Fluid resuscitation is recommended in septic shock, but the specific indications for fluids have not been established. Our aim was to investigate the indications currently used for fluid resuscitation and the effect of fluid on these indications in patients with septic shock admitted to the intensive care unit (ICU). This was a post-hoc analysis of the CLASSIC trial, where patients with septic shock were randomized to fluid restriction or standard care. We recorded indications for and effect of each fluid bolus during the first 24hours. In total, 256 fluid boluses were administered on 515 indications to the 76 patients in the standard care group. The most frequent indications were low blood pressure/increase in noradrenalin dose (199 boluses, 78%), high lactate (94, 37%), and low urinary output (68, 27%). While the analyses of all 418 fluid boluses given in all 151 patients failed to show any effect of fluid on these variables, the data did suggest that time from randomization altered the effect; fluid may have increased urinary output when given early and increased noradrenalin dose when given later. For 56% of the fluid boluses given on the most frequent indications, a second fluid bolus was given on the same indication. In ICU patients with septic shock, low blood pressure, high lactate, and low urinary output were the most frequent indications for fluid. The effects of fluids when given on these indications were less clear, but may dependent on the time course of sepsis resuscitation.