End Of Cardiopulmonary Resuscitation Research Articles

Explorative study on lower inflection point dynamics during cardiopulmonary resuscitation: Potential implications for airway management

IntroductionIn patients undergoing cardiopulmonary resuscitation (CPR) after an Out-of-Hospital Cardiac Arrest (OHCA), intrathoracic airway closure can impede ventilation, adversely affecting patient outcomes. This explorative study investigates the evolution of intrathoracic airway closure by analyzing the lower inflection point (LIP) during the inspiration phase of CPR, aiming to identify the potential thresholds for alveolar recruitment. Methods and materialsEleven OHCA patients undergoing CPR with endotracheal intubation and manual bag ventilation were included. Flow and pressure measurements were obtained using Sensirion SFM3200AW and Wika CPT2500 sensors attached to the endotracheal tube, connected to a Surface Go Tablet for data collection. Flow data was analyzed in Microsoft Excel, while pressure data was processed using the Wika USBsoft2500 application. Analysis focused on the inspiration phase of the first 6–8 breaths, with an additional 2 breaths recorded and analyzed at the end of CPR. ResultsAcross the cohort, the median tidal volume was 870.00 milliliter (mL), average flow was 31.90 standard liters per minute (slm), and average pressure was 17.21 cmH2O. The calculated average LIP was 31.47 cmH2O. Most cases (72.7%) exhibited a negative trajectory in LIP evolution during CPR, with 2 cases (18.2%) showing a positive trajectory and 1 case remaining inconclusive. The average LIP in the first 8 breaths was significantly higher than in the last 2 breaths (p = 0.018). No significant correlation was found between average LIP and return of spontaneous circulation (ROSC), compression depth, frequency, or end-tidal CO2 (EtCO2). However, a significant negative correlation was observed between the average LIP of the last 2 breaths and CPR duration (p = 0.023). Validation: LIP calculation in low-flow ventilations using the novel mathematical method yielded values consistent with those reported in the literature. Discussion/conclusionThese explorative data demonstrate a predominantly negative trajectory in LIP evolution during CPR, suggesting potential challenges in maintaining airway patency. Limitations include a small sample size and sensor recording issues. Further research is warranted to explore the evolution of LIP and its implications for personalized ventilation strategies in CPR.

Deep Learning Strategy for Sliding ECG Analysis during Cardiopulmonary Resuscitation: Influence of the Hands-Off Time on Accuracy.

This study aims to present a novel deep learning algorithm for a sliding shock advisory decision during cardiopulmonary resuscitation (CPR) and its performance evaluation as a function of the cumulative hands-off time. We retrospectively used 13,570 CPR episodes from out-of-hospital cardiac arrest (OHCA) interventions reviewed in a period of interest from 30 s before to 10 s after regular analysis of automated external defibrillators (AEDs). Three convolutional neural networks (CNNs) with raw ECG input (duration of 5, 10, and 15 s) were applied for the shock advisory decision during CPR in 26 sequential analyses shifted by 1 s. The start and stop of chest compressions (CC) can occur at arbitrary times in sequential slides; therefore, the sliding hands-off time (sHOT) quantifies the cumulative CC-free portion of the analyzed ECG. An independent test with CPR episodes in 393 ventricular fibrillations (VF), 177 normal sinus rhythms (NSR), 1848 other non-shockable rhythms (ONR), and 3979 asystoles (ASYS) showed a substantial improvement of VF sensitivity when increasing the analysis duration from 5 s to 10 s. Specificity was not dependent on the ECG analysis duration. The 10 s CNN model presented the best performance: 92-94.4% (VF), 92.2-94% (ASYS), 96-97% (ONR), and 98.2-99.5% (NSR) for sliding decision times during CPR; 98-99% (VF), 98.2-99.8% (ASYS), 98.8-99.1 (ONR), and 100% (NSR) for sliding decision times after end of CPR. We identified the importance of sHOT as a reliable predictor of performance, accounting for the minimal sHOT interval of 2-3 s that provides a reliable rhythm detection satisfying the American Heart Association (AHA) standards for AED rhythm analysis. The presented technology for sliding shock advisory decision during CPR achieved substantial performance improvement in short hands-off periods (>2 s), such as insufflations or pre-shock pauses. The performance was competitive despite 1-2.8% point lower ASYS detection during CPR than the standard requirement (95%) for non-noisy ECG signals. The presented deep learning strategy is a basis for improved CPR practices involving both continuous CC and CC with insufflations, associated with minimal CC interruptions for reconfirmation of non-shockable rhythms (minimum hands-off time) and early treatment of VF (minimal pre-shock pauses).

401.9: Capnometry Values Are a Renal Transplant Evolution Predictor in Uncontrolled Cardiac Arrest Death Donors

Introduction: The evaluation of a potential donor patient involves a series of tests and molecular markers to assess the suitability of an organ and the safety for the recipient. A fundamental marker used in out-of-hospital emergency medicine is capnometry, which allows us to indirectly, but accurately, evaluate the potential donor’s organs’ perfusion. These values could help determine the adequacy of a possible donor in an uncontrolled non-heart beating donation (DACD) and donor selection during out-of-hospital medical emergencies. Capnometry values during cardiopulmonary resuscitation (CPR) are a renal transplant evolution predictor in DACD. Method: Ours is a retrospective study of DACD Maastricht type IIa during a calendar year. The inclusion criteria of the study were: patients who have suffered a witnessed cardiac arrest; age between 16 and 60; asystole electrocardiographic pattern; less than 15 minutes until advanced life support (ALS) arrival; at least 20 minutes of CPR; less than 120 minutes until arrival at the hospital; absence of thorax and abdomen exsanguinating lesions; absence of suspicion of neoplastic, infectious diseases or intravenous drug users (IDUs); chest circumference compatible with chest compression system for donors; and being on hemodialysis and on the renal transplant waiting list for recipients. The data collected from the donors were: age, sex, body mass index, medical history, cause of death, CPR start time, ALS arrival time, time of arrival at the hospital, time of death, cold ischemia and warm ischemia time of each organ, and capnometry values at the begining, at the middle point and at the end of CPR. As from the recipients, collected data were: transplanted organ, cause of chronic kidney disease (CKD), starting date of dialysis, number and type of transplant incompatibilities, renal failure, acute rejection, number of dialysis sessions after transplant, urologic complications, transplant-related infections, serum creatinine levels on 1st, 7th, 15th, 30th, 90th, 180th and 360th days after transplant, levels of proteinuria on 1st, 7th, 15th, 30th, 90th, 180th and 360th days after transplant, one-year transplanted organ survival, one-year recipient patient survival. The quantitative variables are summarized with their median and interquartile range (IR), and the qualitative variables are presented with their distribution of absolute (n) and relative (%) frequencies. We evaluated the correlation between capnometry values of the donor (at the beginning and at the middle point of CPR, and during hospital transference) with creatinine and proteinuria levels on the specified days using the Spearman correlation test. The association between qualitative variables with the capnometry values was evaluated with the Wilcoxon test. For all these tests, a p <0.05 was the accepted level of statistical significance. Results: During a calendar year, 34 donors were studied. The mean age of the donors was 46.9 years, and 82.4% of them were male. The median capnometry value was: 21.3 +/- 12 at the beginning of CPR, 27.4 +/- 12.2 at the middle point of CPR, and 23 +/- 11.7 during hospital transference. The analysis of the correlation between at-the-middle-point-of-CPR and hospital-transference capnometry values, and creatinine and proteinuria levels, showed a statistically significant moderate-to-high negative correlation. Also, a statistically significant association was observed between hospital-transference capnometry values and the number of after-transplant dialysis sessions the receptor needed. Conclusion: Capnometry is a useful tool to determine kidney transplant viability and prognosis. There is an association between donors capnometry values at the middle point of CPR and during hospital transference, and creatinine and proteinuria levels of the recipient, and another association between high capnometry values during hospital transference and a less need of after-transplant dialysis.

446 Relationship between out of hospital cardiac arrest and COVID-19 pandemic: impact on outcome

AimsDuring 2020, Italy was hit by the pandemic of the ‘Coronavirus disease 2019’ (COVID-19) with an incidence/100 000 citizens characterized by two peaks. An increase in out-of-hospital cardiac arrest (OHCA) mortality during the first pandemic peak has already been described, but there are few data on the whole year. The goal of our study is to evaluate the impact of the pandemic on post-OHCA mortality.MethodsWe considered patients with OHCA in Varese territory from January to December 2020 with medical aetiology according with Utstein 2014 classification. The primary endpoint of the study was the assessment of acute post-arrest mortality and which parameters influence this outcome. In particular, both the role of pandemic peaks (‘first peak’ from 11 March 2020 to 23rd May 2020 and ‘second peak’ from 7 October 2020 to 31 December 2020) and the average rescue times, i.e.: (i) interval between OHCA and call for first aid (delay in activation of assistance); (ii) the interval between the call and the arrival of the rescue vehicles (delay in the arrival of the first aid) and finally; (iii) the time between the arrival of the rescue vehicles and the end of Cardiopulmonary Resuscitation (CPR), interrupted due to death or Recovery of Spontaneous Circulation (ROSC). Finally, we performed a multivariate analysis to assess which of the variables considered had the greatest impact on the outcome.ResultsWe analysed 708 patients (mean age 76 + 14.09 years; 40% women). Overall mortality was 89%. During the peaks there was an increase in mortality compared to the pre-pandemic period (first peak 96% vs. 83%, OR 4.49; second peak 92% vs. 83%, OR 2.45) (Figure 1). The time between the collapse and the call for help was significantly higher during the first pandemic peak compared to the second peak and the pre-pandemic period (P = 0.003); the time between the call and the arrival on the patient was significantly longer during both pandemic peaks than in the previous period (P = 0.002) and there was no significant difference in CPR duration time between the periods analysed. In a multivariate model, the only time associated with an increase in mortality is the period between the call for help and the arrival on the patient, regardless of the COVID-19 pandemic.Figure 1446 ConclusionsDuring the COVID-19 pandemic there has been an increase in mortality of patients with OHCA. Among the variables considered, the increase in mortality is mainly associated with the delay in the arrival of emergency vehicles on site. This delay, although decreasing, was also maintained during the second peak of the pandemic.

Software annotation of defibrillator files: Ready for prime time?

BackgroundHigh-quality chest compressions are associated with improved outcomes after cardiac arrest. Defibrillators record important information about chest compressions during cardiopulmonary resuscitation (CPR) and can be used in quality-improvement programs. Defibrillator review software can automatically annotate files and measure chest compression metrics. However, evidence is limited regarding the accuracy of such measurements. ObjectiveTo compare chest compression fraction (CCF) and rate measurements made with software annotation vs. manual annotation vs. limited manual annotation of defibrillator files recorded during out-of-hospital cardiac arrest (OHCA) CPR. MethodsThis was a retrospective, observational study of 100 patients who had CPR for OHCA. We assessed chest compression bioimpedance waveforms from the time of initial CPR until defibrillator removal. A reviewer revised software annotations in two ways: completely manual annotations and limited manual annotations, which marked the beginning and end of CPR and ROSC, but not chest compressions. Measurements were compared for CCF and rate using intraclass correlation coefficient (ICC) analysis. ResultsCase mean rate showed no significant difference between the methods (108.1–108.6 compressions per minute) and ICC was excellent (>0.90). The case mean (±SD) CCF for software, manual, and limited manual annotation was 0.64 ± 0.19, 0.86 ± 0.07, and 0.81 ± 0.10, respectively. The ICC for manual vs. limited manual annotation of CCF was 0.69 while for individual minute epochs it was 0.83. ConclusionSoftware annotation performed very well for chest compression rate. For CCF, the difference between manual and software annotation measurements was clinically important, while manual vs. limited manual annotation were similar with an ICC that was good-to-excellent.

Abstract 144: Differing Pattern of ECG Changes During Resuscitation From Pulseless Electrical Activity Depending on Etiology

Introduction: Pulseless electrical activity (PEA) is a frequent initial rhythm in in-hospital cardiac arrest. ECG changes during cardiopulmonary resuscitation (CPR) have been linked to prognosis; QRS complex narrowing and increase in QRS-rate/heart rate was observed before return of spontaneous circulation (ROSC). Our hypothesis was that ECG changes during CPR of patients with cardiac arrest with initial PEA could also be different depending on etiology of arrest. Methods: Patients with cardiac arrest with initial PEA at St. Olav University Hospital (Trondheim, Norway) between January 2009 and January 2012 were prospectively included. QRS duration and heart rate were measured at all pauses in chest compressions. Etiologies were categorized as ‘Cardiac’ or ‘Other’. Trends in the material were inspected using additive mixed effects models for the last 18 minutes before ROSC or end of CPR and development of QRS width was analyzed using linear mixed effects models based on these trends. Results: A total of 63 patients for whom a reliable cause of arrest could be identified retrospectively were included. 1844 combined measurements of QRS width and heart rate were made. According to the additive mixed effects model the development in heart rate was similar in both etiology groups. The change in QRS width differed in patients who obtained ROSC, with the Cardiac group narrowing more than the other group, and both groups ending at essentially the same QRS widths at ROSC (figure). By the linear mixed effects model this difference in change was statistically significant (p=0.04). In patients who did not have ROSC, the cardiac group had significantly (p=0.001, linear mixed effects model) wider QRS complexes, but the change towards ROSC was the same in both groups. Conclusion: During the last 18 minutes before ROSC ECG characteristics differed depending on etiology, with cardiac etiologies having wider QRS complexes in the no-ROSC groups and narrowing more towards ROSC in the ROSC groups.

Comparison of manual pulse palpation, cardiac ultrasonography and Doppler ultrasonography to check the pulse in cardiopulmonary arrest patients

ObjectiveFor health professionals, the absence of pulse checked by manual palpation is a primary indicator for initiating chest compressions in patients considered to have cardiopulmonary arrest (CA). However, using a pulse check to evaluate perfusion during CA may be associated with some risks of its own. Our objective was to compare the efficiency of cardiac ultrasonography (CUSG), Doppler ultrasonography (DUSG), and manual pulse palpation methods to check the pulse in CA patients. Material and methodsThis study was prospectively performed in 137 patients older than 16 years of age who underwent cardiopulmonary resuscitation (CPR). CUSG, DUSG, and manual pulse palpation were practiced simultaneously as suggested in the relevant guidelines. Findings of the patients were recorded at the first min, at min 15 and at the end of CPR. SPSS 18.0 was used for statistical analysis. FindingsA total of 72.3% (n = 99) of the cardiopulmonary arrest incidents occurred out-of-hospital. CUSG (4.76 ± 2.19, 4.33 ± 2.17, and 3.68 ± 2.14 s), DUSG (9.59 ± 2.37, 8.22 ± 2.86, and 7.60 ± 2.83 s), and manual pulse palpation (10.76 ± 1.03, 9.72 ± 3.01, and 9.29 ± 3.36 s) measurements of the first, second, and last inspections were detected, respectively. The false negative rates (100%, 28%, and 0%) and false positive rates (5.3%, 3.5%, and 0%) of manual pulse palpation the first, second, and last inspections were calculated, respectively, as well. ConclusionThe use of real-time CUSG during resuscitation provides a substantial contribution to the resuscitation team. CUSG will allow earlier and more accurate detection of pulse than manual pulse palpation and DUSG.

One-year follow-up of neurological status of patients after cardiac arrest seen at the emergency room of a teaching hospital

ABSTRACTObjective:To describe neurological status and associated factors of survivors after cardiac arrest, upon discharge, and at 6 and 12 month follow-up.Methods:A cohort, prospective, descriptive study conducted in an emergency room. Patients who suffered cardiac arrest and survived were included. A one-year consecutive sample, comprising 285 patients and survivors (n=16) followed up for one year after discharge. Neurological status was assessed by the Cerebral Performance Category before the cardiac arrest, upon discharge, and at 6 and 12 months after discharge. The following factors were investigated: comorbidities, presence of consciousness upon admission, previous cardiac arrest, witnessed cardiac arrest, location, cause and initial rhythm of cardiac arrest, number of cardiac arrests, interval between collapse and start of cardiopulmonary resuscitation, and between collapse and end of cardiopulmonary resuscitation, and duration of cardiopulmonary resuscitation.Results:Of the patients treated, 4.5% (n=13) survived after 6 and 12 months follow-up. Upon discharge, 50% of patients remained with previous Cerebral Performance Category of the cardiac arrest and 50% had worsening of Cerebral Performance Category. After 6 months, 53.8% remained in the same Cerebral Performance Category and 46.2% improved as compared to discharge. After 12 months, all patients remained in the same Cerebral Performance Category of the previous 6 months. There was no statistically significant association between neurological outcome during follow-up and the variables assessed.Conclusion:There was neurological worsening at discharge but improvement or stabilization in the course of a year. There was no association between Cerebral Performance Category and the variables assessed.

Abdominal oxygen saturation for monitoring return of spontaneous circulation in out-of-hospital cardiac arrest using near infrared spectrophometry

AimWe used near-infrared spectrophotometry to assess the initial and final abdominal and cerebral saturations during cardiopulmonary resuscitation (CPR) of patients with out-of-hospital cardiac arrest to determine if there is a correlation between increase in these saturation values and return of spontaneous circulation. Materials and methodsWe evaluated 34 patients with out-of-hospital cardiac arrest without witnesses brought to our emergency department. Abdominal and cerebral saturations were measured using near-infrared spectrophotometry from the start of CPR. Cardiopulmonary resuscitation was performed for a maximum of 30 minutes. The effect of abdominal saturations in patients with or without spontaneous circulation restored through CPR was then assessed. ResultsThirty-four patients (17 males + females) with a mean age of 63.06 ± 11.66 years were included in the study. A significant correlation was determined between increase in abdominal saturations measured at the start and end of CPR and the return of spontaneous circulation (P < .001). A good positive correlation was also identified between abdominal saturation and return of spontaneous circulation. ConclusionPatients with increased abdominal and cerebral saturation values have a higher survival rate after appropriate CPR. This noninvasive measurement system and monitoring of patients during CPR may be a good method of predicting return of spontaneous circulation and assessing abdominal perfusion.

Near infrared spectrophotometry (cerebral oximetry) in predicting the return of spontaneous circulation in out-of-hospital cardiac arrest

AimWe assessed out-of-hospital cardiac arrest patients’ cerebral oxygenation during cardiopulmonary resuscitation (CPR) using near infrared spectrophotometry (NIRS). We evaluated the relation between a rise in patients’ cerebral saturation values between the start and end of CPR and return of spontaneous circulation. Materials and methodsTwenty-three patients with unwitnessed out-of-hospital cardiac arrest and brought to our emergency department by emergency ambulance were evaluated. Cerebral saturations from time of start of CPR were measured using NIRS. CPR was performed for a maximum of 30 min. The relation between cerebral saturations in patients with or without return of spontaneous circulation was then evaluated. ResultsTwenty-three patients, 12 (52.2%) female and 11 (47.8%) male, with a mean age of 64.09 ± 13.66 were included. A correlation was determined between a rise in cerebral saturation measured throughout CPR and the return of spontaneous circulation (P < .001). ConclusionPatients whose cerebral saturation values measured with NIRS rise during CPR have a higher post-resuscitation survival rate. Monitoring of patients during CPR with this non-invasive technique may be a good method for predicting return of spontaneous circulation.

Extracorporeal Life Support during Cardiac Arrest Resuscitation in a Porcine Model of Ventricular Fibrillation

Implementation barriers for extracorporeal life support in out-of-hospital cardiac arrest (OHCA) include initiation delay and candidate selection. We explored ischemia duration, cardiopulmonary resuscitation (CPR) duration, and physiologic variables that discriminated animals with return of spontaneous circulation (ROSC). We instrumented eight female swine (31.9 ± 9.8 kg) with femoral artery and external jugular vein cannula. After 8 (n = 4) or 15 (n = 4) minutes ventricular fibrillation (VF), animals received 30, 40, 50, or 60 minutes of CPR and then drugs (.6 U/kg vasopressin, .1 mg/kg epinephrine, .1 mg/kg propranolol, sodium bicarbonate as indicated) after 5 minutes of CPR. Extracorporeal membrane oxygenation (ECMO) flow rate was 3 L/min ≤2 hours and then 1.5 L/min ≤2 hours before weaning. Animals were defibrillated (150 J biphasic) ≥15 minutes ECMO. Primary outcome for successful resuscitation was ROSC (organized rhythm with systolic blood pressure &gt;80 mmHg). We measured arterial blood gas, electrolytes, mean arterial pressure (MAP), coronary perfusion pressure (CPP), and five quantitative VF waveform measures at key intervals. Continuous variables were compared with two-sample t test. All 8-minute VF animals were successfully resuscitated and had ROSC. MAP was higher at the beginning (27.0 ± 7.1 vs. 15.0 ± 4.4; p = .03) and end (31.3 ± 12.8 vs. 11.5 ± 7.3; p = .03) of CPR in animals successfully resuscitated. CPP was higher at the beginning of CPR (11.9 ± 4.6 vs. 3.3 ± 2.2; p = .01) and the end of CPR (18.5 ± 12.1 vs. .9 ± 1.4; p = .03) among animals with ROSC. Amplitude spectrum area (AMSA) was superior at the end of CPR (–2.0 ± 1.8 vs. –5.0 ± 1.4; p = .04) in animals successfully resuscitated. In a porcine OHCA model, MAP and CPP at the beginning and end of CPR were higher in animals successfully resuscitated. AMSA was superior at the end of CPR in animals successfully resuscitated.

Survival after in-hospital cardiopulmonary resuscitation in a major referral center

Aim:This study was undertaken to assess the demographics, clinical parameters and outcomes of patients undergoing cardiopulmonary resuscitation (CPR), by the code blue team at our center to compare with other centers.Materials and Methods:Data were collected retrospectively from all adult patients who underwent CPR at our hospital from 2007 to 2008. CPR was performed on 290 patients and it was given 313 times. Clinical outcomes of interest were survival at the end of CPR and survival at discharge from the hospital. Factors associated with survival were evaluated via binomial and chi square-tests.Results:Of the 290 patients included, 95 patients (30.4%) had successful CPR. However, only 35 patients (12%) were alive at discharge. The majority requiring CPR were above 60 years of age (61.7%). Males required CPR more than females. There were 125 women (43.1%) and 165 males (56.9%) aged 3 to 78 (average 59.6) years. Majority (179) of the cases (61.7%) were above 60 years of age. Regarding the various wards, 54 cases (17.3%) were in the internal medicine ward, 63 cases (20.1%) in the surgery ward, 1 case (0.3%) in the clinic, 11 cases (3.5%) in the paraclinic, 116 cases (37.1%) in the emergency (ER), 55 cases (17.5%) in the Intensive Care Unit (ICU) and Coronary Care Unit (CCU), and 13 cases (4.2%) were in other wards. Cardiac massage was done in 133 cases (42.5%), defibrillation only via electroshock 3 cases (1%), and both were used in177 cases (56.5%). The ER had the most cases of CPR. Both cardiac massage and electroshock defibrillation were needed in most cases.Conclusion:In-hospital CPR for cardiopulmonary arrest was associated with 30.4% success at our center at the end of CPR but only 12% were alive at discharge. Duration of CPR >10 minutes was predictive of significantly decreased survival to discharge.

Outcome of cardiopulmonary resuscitation - predictors of survival.

To assess the outcomes of patients undergoing cardiopulmonary resuscitation (CPR). A cross-sectional study. Shifa International Hospital, Islamabad from January 2005 to December 2005. Data were collected retrospectively of all adult patients who underwent CPR. Clinical outcomes of interest were survival at the end of CPR and survival at discharge from hospital. Factors associated with survival were evaluated using logistic regression analysis. Of the 159 patients included, 55 (35%) were alive at the end of CPR and 17 (11%) were discharged alive from the hospital. At the end of CPR, univariate logistic regression analysis found the following factors associated with survival: cardiac arrest within hospital as compared to outside the hospital (odds ratio = 2.8, 95% CI = 1.27-6.20, p-value = 0.01), both cardiac and pulmonary arrest as compared to either cardiac or pulmonary arrest (odds ratio = 0.37, 95%CI = 0.19- 0.73, p-value = 0.004), asystole as cardiac rhythm at presentation (odds ratio = 0.47, 95%CI = 0.24-0.93, p-value = 0.03), and total atropine dose given during CPR (odds ratio = 0.78, 95%CI = 0.62-0.97, p-value = 0.02). In multivariate logistic regression, cardiac arrest within hospital (odds ratio = 2.52, 95%CI = 1.06-5.99, p-value = 0.04) and both cardiac and pulmonary arrest as compared to cardiac or pulmonary arrest (odds ratio = 0.44, 95%CI = 0.21-0.91, p-value = 0.03) were associated with survival at the end of CPR. At the time of discharge from hospital, univariate logistic regression analysis found following factors that were associated with survival: cardiac arrest within hospital (odds ratio = 8.4, 95%CI = 1.09-65.64, p-value = 0.04), duration of CPR (odds ratio = 0.91, 95%CI = 0.85-0.96, p-value = 0.001), and total atropine does given during CPR (odds ratio = 0.68, 95%CI = 0.47-0.99, p-value = 0.05). In multivariate logistic regression analysis cardiac arrest within hospital (odds ratio = 8.69, 95%CI = 1.01-74.6, p-value = 0.05) and duration of CPR (odds ratio = 0.92, 95%CI = 0.87-0.98, p-value = 0.01) were associated with survival at discharge from hospital. In-hospital cardiopulmonary arrest was associated with better clinical outcomes as compared to outside hospital arrest. Public education is needed to improve clinical outcomes in patients who need CPR outside hospital.

Platelet activation with massive formation of thromboxane A2 during and after cardiopulmonary resuscitation.

Hypoxia and ischemia cause endothelial cell damage with consequent platelet activation. The hypothesis that human cardiac arrest accelerates platelet activation and the formation of prostanoids was tested. Prospective, observational cohort study. Emergency Department and general Intensive Care Unit in a city hospital. Basic and advanced life support. Forty-seven out-of-hospital cardiac arrest patients. The patients were classified into two groups, those who were resuscitated (n = 18) and those who died (n = 29). Serial levels of platelet aggregation, thromboxane B2 (TXB2), 11-dehydro-TXB2 and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were measured. The results of measurements and demographic data were compared between the groups. Platelet counts decreased at the end of cardiopulmonary resuscitation (CPR), the decrease of the platelet counts showed statistical significance especially in the patients who died (p < 0.001). Platelet aggregation induced by adenosine diphosphate, epinephrine and collagen decreased to the lower limits of normal during and after CPR. Although high values of TXB2 and 11-dehydro-TXB2 continued throughout the study period in the resuscitated patients, 6-keto-PGF1 alpha decreased to the normal range (22.7 +/- 3.6 pg.ml-1. p < 0.05 at -24 h after arrival at the Emergency Department. Platelet activation with the massive formation of thromboxane A2 (TXA2) occurs in patients with out-of-hospital cardiac arrest. Successful resuscitation is not associated with the balanced production of PGI2 against the TXA2 formation.

Evaluation of An End-Tidal CO2 Detector During Pediatric Cardiopulmonary Resuscitation

To determine the utility of a disposable colorimetric end-tidal CO2 detector during pediatric cardiopulmonary resuscitation (CPR) for (1) confirming endotracheal tube (ETT) position, and (2) assessing the relationship between end-tidal CO2 recorded by this method and outcome of pediatric CPR. Prospective observations during CPR in a university children's hospital. Forty children (28 male, 12 female) aged 1 week to 10 years (25 children aged < or = 1 year, mean age 27.2 months, median 7 months), weighing 2.5 to 40 kg (31 children weighing < or = 15 kg, mean 10.94 kg, median 7 kg) who underwent a total of 48 endotracheal intubations during CPR. After intubation, ETT position was verified by usual clinical methods including direct visualization. The device was attached between the ETT and ventilation bag, the patient was manually ventilated, and a first reading was obtained. Any color change from purple (Area A, end-tidal CO2 < 0.5%) to tan or yellow (Area B or C, end-tidal CO2 > or = 0.5%) was considered to be positive for airway intubation. CPR was conducted as per Pediatric Advanced Life Support guidelines. A second reading was obtained when the decision to discontinue CPR was made. All nine esophageal tube positions were correctly identified by the detector. Thirty-three of 39 tracheal tube positions were correctly identified (P < .001). For verifying ETT position, the device had a sensitivity of 84.6%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 60%. Readings were obtained at the end of CPR in 25 patients. All 13 patients who regained spontaneous circulation and survived to ICU admission had a second reading in the C range, while none of the 12 patients with a second reading in the A or B range survived. Both the first and second end-tidal CO2 readings in the C range correlated significantly with short-term survival (P = .01 and P < .001, respectively). Two patients were eventually discharged from the hospital. During CPR a positive test confirms placement of the ETT within the airway, whereas a negative test indicates either esophageal intubation or airway intubation with poor or absent pulmonary blood flow and requires an alternate means of confirmation of tube position. The detector may be of prognostic value for return of spontaneous circulation and short-term survival.