Resuscitation

Can drugs ever improve outcome after cardiac arrest?

Theresa Mariero Olasveengen — 2012-03-19

This issue of Resuscitation includes a review of beta-blocker treatment for cardiac arrest. At first, the very idea of administering a beta-blocker simultaneously with the recommended vasopressor might seem like driving your car with one foot on the brakes and the other on the gas pedal. How did we get here?

Pediatric ECPR: Standard of care?

Laurance Lequier, Allan de Caen — 2012-04-05

Twenty years have passed since the first published reports of rapid deployment extracorporeal membrane oxygenation (ECMO) as rescue therapy during CPR (ECPR) for children with cardiac disease. These were fascinating as they showed that survival was possible after initiation of mechanical circulatory support following prolonged periods of CPR. Since then, multiple case reports, single-center case series, meta-analyses and reviews of the Extracorporeal Life Support Organization (ELSO) registry database have described the use of cardiac ECMO and ECPR in an ever expanding list of indications. Recently reported single-center case series of ECPR rescue for children with cardiac disease describe survival to hospital discharge of between 34% and 51%. The use of ECPR in pediatric patients appears to offer a survival advantage over conventional CPR based on review of the NRCPR database. In addition, the most recent ILCOR treatment recommendations for pediatric resuscitation state that “…ECPR may be beneficial for infants and children with cardiac arrest if they have heart disease amenable to recovery or transplantation and the arrest occurs in a highly supervised environment such as an ICU with existing clinical protocols and available expertise and equipment to rapidly initiate ECPR”.

Endothelial damage after cardiac arrest—“Endotheliitis”

Clifton W. Callaway — 2012-03-19

The article by Grundmann and colleagues reports on the participation of endothelial glycocalyx (EG) damage in post-cardiac arrest illness and provides an opportunity to ponder how the endothelium participates in recovery after cardiac arrest. By providing the lining of all of the vasculature, the endothelium is a critical tissue that regulates many diverse processes. After global ischemia and reperfusion during cardiac arrest, the endothelial surface in many organs and territories might be stripped of its normal EG lining. This situation can be conceptualized as diffuse endothelial damage or “endothelitis.”

Predictive scores, friend or foe for the cardiac arrest patient

Niklas Nielsen — 2012-03-19

Outcome for patients resuscitated from cardiac arrest is associated with a multitude of factors, both related to the individual patient, such as age and comorbidities; as well as to circumstances around the cardiac arrest event, such as time from arrest to start of cardiopulmonary resuscitation, time to return of spontaneous circulation and the nature of cardiac rhythm at first assessment. These factors, combined with laboratory tests and clinical investigations at hospital admission, may already harbour the subsequent fate of individuals with respect to mortality and poor neurological outcome. Accordingly, utilizing these pieces of information, risk prediction scores may be calculated. At best this would predict outcome for the individual patient, but it may nevertheless be accurate for the average patient in a cardiac arrest population.

Therapeutic hypothermia after return of spontaneous circulation: Should be offered to all?

David Szpilman, Marcelo Magalhães, Ricardo Turon Costa da Silva — 2012-03-14

Out-of-hospital cardiac arrest (OHCA) has an incidence of 52.1 per 100,000 population, making it the third leading cause of death in North America. The median survival rate after emergency medical services (EMS)-treated cardiac arrest is 8.4% (3.0–16.3%). Several factors contribute to the large variation in survival. The Utstein Style template was created to enable uniform reporting of cardiac arrest data by EMS personnel, thus allowing researchers to compare “apples with apples”.

Use of beta-blockers for the treatment of cardiac arrest due to ventricular fibrillation/pulseless ventricular tachycardia: A systematic review

2012-02-03

Abstract: Introduction: Advanced Life Support guidelines recommend the use of epinephrine during Cardiopulmonary Resuscitation (CPR), as to increase coronary blood flow and perfusion pressure through its alpha-adrenergic peripheral vasoconstriction, allowing minimal rises in coronary perfusion pressure to make defibrillation possible. Contrasting to these alpha-adrenergic effects, epinephrine's beta-stimulation may have deleterious effects through an increase in myocardial oxygen consumption and a reduction of subendocardial perfusion, leading to postresuscitation cardiac dysfunction.Objective: The present paper consists of a systematic review of the literature regarding the use of beta-blockade in cardiac arrest due to ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT).Methods: Studies were identified through MEDLINE electronic databases research and were included those regarding the use of beta-blockade during CPR.Results: Beta-blockade has been extensively studied in animal models of CPR. These studies not only suggest that beta-blockade could reduce myocardial oxygen requirements and the number of shocks necessary for defibrillation, but also improve postresuscitation myocardial function, diminish arrhythmia recurrences and prolong survival. A few case reports described successful beta-blockade use in patients, along with two prospective human studies, suggesting that it could be safe and effectively used during cardiac arrest in humans.Conclusion: Even though the existing literature points toward a beneficial effect of beta-blockade in patients presenting with cardiac arrest due to VF/pulseless VT, high quality human trials are still lacking to answer this question definitely.

Novel biomarkers in diagnosing cardiac ischemia in the emergency department: A systematic review

Steve Lin, Hiroyuki Yokoyama, Valeria E. Rac, Steven C. Brooks — 2011-12-26

Abstract: Background: Novel biomarkers of myocardial ischemia and inflammatory processes have the potential to improve diagnostic accuracy of acute coronary syndrome (ACS) within a shorter time interval after symptom onset.Objective: The objective was to review the recent literature and evaluate the evidence for use of novel biomarkers in diagnosing ACS in patients presenting with chest pain or symptoms suggestive of cardiac ischemia to the emergency department or chest pain unit.Methods: A literature search was performed in MEDLINE, EMBASE, Cochrane DSR, ACP Journal Club, DARE, CCTR, CMR, HTA, and NHSEED for studies from 2004 to 2010. We used the inclusion criteria: (1) human subjects, (2) peer-reviewed articles, (3) enrolled patients with ACS, acute myocardial infarction or undifferentiated signs and symptoms suggestive of ACS, and (4) English language or translated manuscripts. Two reviewers conducted a hierarchical selection and assessment using a scale developed by the International Liaison Committee on Resuscitation.Results: Out of a total 3194 citations, 58 articles evaluating 37 novel biomarkers were included for final review. Forty-one studies did not support the use of their respective biomarkers. Seventeen studies supported the use of 5 biomarkers, particularly when combined with cardiac-specific troponin: heart fatty acid-binding protein, ischemia-modified albumin, B-type natriuretic peptide, copeptin, and matrix metalloproteinase-9.Conclusion: In patients presenting to the emergency department with chest pain or symptoms suggestive of cardiac ischemia, there is inadequate evidence to suggest the routine testing of novel biomarkers in isolation. However, several novel biomarkers have the potential to improve the sensitivity of diagnosing ACS when combined with cardiac-specific troponin.

Suppression of the cardiopulmonary resuscitation artefacts using the instantaneous chest compression rate extracted from the thoracic impedance

E. Aramendi, U. Ayala, U. Irusta, E. Alonso, T. Eftestøl, J. Kramer-Johansen — 2011-12-23

Abstract: Aim: To demonstrate that the instantaneous chest compression rate can be accurately estimated from the transthoracic impedance (TTI), and that this estimated rate can be used in a method to suppress cardiopulmonary resuscitation (CPR) artefacts.Methods: A database of 372 records, 87 shockable and 285 non-shockable, from out-of-hospital cardiac arrest episodes, corrupted by CPR artefacts, was analysed. Each record contained the ECG and TTI obtained from the defibrillation pads and the compression depth (CD) obtained from a sternal CPR pad. The chest compression rates estimated using TTI and CD were compared. The CPR artefacts were then filtered using the instantaneous chest compression rates estimated from the TTI or CD signals. The filtering results were assessed in terms of the sensitivity and specificity of the shock advice algorithm of a commercial automated external defibrillator.Results: The correlation between the mean chest compression rates estimated using TTI or CD was r=0.98 (95% confidence interval, 0.97–0.98). The sensitivity and specificity after filtering using CD were 95.4% (88.4–98.6%) and 87.0% (82.6–90.5%), respectively. The sensitivity and specificity after filtering using TTI were 95.4% (88.4–98.6%) and 86.3% (81.8–89.9%), respectively.Conclusions: The instantaneous chest compression rate can be accurately estimated from TTI. The sensitivity and specificity after filtering are similar to those obtained using the CD signal. Our CPR suppression method based exclusively on signals acquired through the defibrillation pads is as accurate as methods based on signals obtained from CPR feedback devices.

Immediate coronary angiogram in comatose survivors of out-of-hospital cardiac arrest—An Australian study

Vinodh Bhagyalakshmi Nanjayya, Vineet Nayyar — 2011-12-16

Abstract: Introduction: The role of immediate coronary angiography and percutaneous coronary intervention (angio±PCI), amongst comatose survivors of out-of-hospital cardiac arrest is unclear. This study was undertaken to evaluate if immediate angio±PCI compared to no initial intervention improves neurological outcome at hospital discharge amongst comatose survivors of out-of-hospital pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF).Methods: All patients admitted to Intensive Care Unit (ICU) following an out-of-hospital VF/pVT arrest from 1/1/2003 to 31/12/2008 were included. Outcome of patients who underwent immediate angio±PCI was compared to those who did not undergo any intervention before admission to ICU. Good outcome was defined as survival to hospital discharge with Cerebral Performance Category (CPC) score of 1 or 2.Results: Thirty-five patients (30 Males, 5 Females, mean age 60.3±10.1), underwent angio±PCI prior to ICU admission. A further 35 patients (20 Males, 15 Females, mean age 61.1±17.6 years) were admitted directly to ICU without undergoing any intervention. Forty percent (14/35) of patients who had immediate coronary intervention survived to hospital discharge with a good outcome compared to 31% (11/35) patients who did not undergo any intervention. After adjusting for other covariates, the probability of good outcome at hospital discharge was related to severity of illness (SAPS-II) score at ICU admission (adj OR=0.87, 95% CI 0.81–0.94, p<0.01). Immediate angio±PCI compared to no intervention was associated with an improved outcome but this difference was statistically not significant (adj OR 1.32, 95% CI 0.26–7.87, p=0.78).Conclusion: Immediate angio±PCI in comatose survivors of out-of-hospital VF/pVT arrest did not lead to better neurological outcome at hospital discharge.

Comparison of ultrasound and X-ray in determining the position of umbilical venous catheters

2011-12-07

Abstract: Objective: Thoraco-abdominal X-ray (TAX) is the most frequent used method to determine the route and tip position (TP) of umbilical venous catheters (UVCs). The aim of this study was to compare ability of TAX and ultrasonography (US) to determine UVC route and TP.Patients and methods: All neonates requiring UVC or admitted to our Paediatric and Neonatal Intensive Care with UVC were included in this prospective study. Catheter position was controlled by TAX and interpreted by the physician in charge of the patient. US examinations were performed by a paediatric radiologist blinded to TAX result. The UVC route (central or not central) and TP determined by each method were compared to the “actual UVC route and TP”, as determined by senior paediatric radiologist and neonatologist referents joint interpretation of TAX and US results.Results: Sixty-one UVCs were assessed in 60 neonates of mean gestational age of 34.7±4.2weeks. To determine catheter route, sensitivity and specificity were respectively 96.4% and 93.9% for US and 92.8% and 78.8% for TAX. To determine catheter tip position, sensitivity and specificity were respectively 93.3% and 95.6% for US and 66.7% and 63.0% for TAX (p<0.001). Failure of TAX to define UVC tip position increased with birth weight (p<0.005).Conclusion: TAX and US are reliable in determining UVC route (central or not) but US examination is superior to TAX in determining UVC TP.

Eleven years of experience with extracorporeal cardiopulmonary resuscitation for paediatric patients with in-hospital cardiac arrest

2012-02-03

Abstract: Purpose: The study aims to describe 11 years of experience with extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital paediatric cardiac arrest in a university affiliated tertiary care hospital.Methods: Paediatric patients who received extracorporeal membrane oxygenation (ECMO) during active extracorporeal cardiopulmonary resuscitation (ECPR) at our centre from 1999 to 2009 were included in this retrospective study. The results from three different cohorts (1999–2001, 2002–2005 and 2006–2009) were compared. Survival rates and neurological outcomes were analysed. Favourable neurological outcome was defined as paediatric cerebral performance categories (PCPC) 1, 2 and 3.Results: We identified 54 ECPR events. The survival rate to hospital discharge was 46% (25/54), and 21 (84%) of the survivors had favourable neurological outcomes.The duration of CPR was 39±17min in the survivors and 52±45min in the non-survivors (p=NS). The patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes (47% (18/38) vs. 44% (7/16), p=NS).The non-survivors had higher serum lactate levels prior to ECPR (13.4±6.4 vs. 8.8±5.1mmol/L, p<0.01) and more renal failure after ECPR (66% (19/29) vs. 20% (5/25), p<0.01).The patients resuscitated between 2006 and 2009 had shorter durations of CPR (34±13 vs. 78±76min, p=0.032) and higher rates of survival (55% (16/29) vs. 0% (0/8), p=0.017) than those resuscitated between 1999 and 2002.Conclusions: In our single-centre experience with ECPR for paediatric in-hospital cardiac arrest, the duration of CPR has become shorter and outcomes have improved in recent years. Higher pre-ECPR lactate levels and the presence of post-ECPR renal failure were associated with increased mortality. The presence of non-cardiac causes of cardiac arrest did not preclude successful ECPR outcomes. The duration of CPR was not significantly associated with poor outcomes in this study.

Perturbation of the endothelial glycocalyx in post cardiac arrest syndrome

2012-02-03

Abstract: Background: The prognosis of immediate survivors of cardiac arrest remains poor, as the majority of these patients develops an inflammatory disorder known as the post-cardiac arrest syndrome (PCAS). Recently, the endothelial glycocalyx has been shown to be a key modulator of vascular permeability and inflammation, but its role in PCAS remains unknown.Methods: Plasma levels of the glycocalyx components syndecan-1, heparan sulfate and hyaluronic acid were measured in 25 patients after immediate survival of cardiac arrest during different phases of PCAS. Twelve hemodynamically stable patients with acute coronary syndrome served as controls.Results: Cardiac arrest resulted in a significant increase in syndecan-1, heparan sulfate and hyaluronic acid levels compared to controls, indicating a shedding of the endothelial glycocalyx as a pathophysiological component of the post cardiac arrest syndrome. The time course differed between the individual glycocalyx components, with a higher increase of syndecan-1 in the early phase of PCAS (2.8-fold increase vs. controls) and a later peak of heparan sulfate (1.7-fold increase) and hyaluronic acid (2-fold increase) in the intermediate phase. Only the plasma levels of syndecan-1 correlated positively with the duration of CPR and negatively with the glycocalyx-protective protease inhibitor antithrombin III. Plasma levels of both syndecan-1 and heparan sulfate were higher in eventual non-survivors than in survivors of cardiac arrest.Conclusion: Our data for the first time demonstrates a perturbation of the endothelial glycocalyx in immediate survivors of cardiac arrest and indicate a potential important role of this endothelial surface layer in the development of post-cardiac arrest syndrome.

Acute kidney injury after cardiac arrest

Horng-Ruey Chua, Neil Glassford, Rinaldo Bellomo — 2011-12-12

Abstract: Aim: Cardiac arrest (CA) in humans causes warm renal ischemia-reperfusion injury, similar to animal models of ischemic acute kidney injury (AKI). We aimed to investigate the incidence and risk associations of AKI after CA, with or without post-resuscitation cardiogenic shock (PRCS).Methods: We examined the renal outcomes of adult patients admitted to the intensive care unit (ICU), who survived for more than 48h following successful resuscitation after CA.Results: Of 105 patients (median age 65 years; 69% male), 58 (55.2%) had PRCS and were on vasoactive drugs beyond 24h; and 9 (8.6%) (all of whom had PRCS) received renal replacement therapy. Only 3 (6.4%) of 47 patients without PRCS had RIFLE-‘I’/‘F’ AKI, compared to 30 (51.7%) of 58 patients with PRCS (p<0.001). Median peak serum creatinine in the non-PRCS group was 102μmol/L (interquartile range 85–115), compared to 155μmol/L (interquartile range 112–267) (p<0.001) in the PRCS group. On multivariate analysis, cumulative noradrenaline dose during the first 24h in ICU, PRCS, and pre-CA renin–angiotensin–aldosterone-system blockade were independently associated with RIFLE-‘I’/‘F’ AKI; while higher serum lactate 12h after CA, baseline creatinine, and PRCS were independently associated with greater rise in creatinine from pre-CA levels. Estimated time without spontaneous circulation, total adrenaline dose and initial cardiac rhythm during CA, had no independent associations with renal outcomes.Conclusions: In the absence of PRCS, CA in isolation is uncommonly associated with significant AKI. The human kidney may be more resistant to warm ischemia-reperfusion injury than previously thought.

Survival and outcome prediction using the Apache III and the out-of-hospital cardiac arrest (OHCA) score in patients treated in the intensive care unit (ICU) following out-of-hospital, in-hospital or ICU cardiac arrest

M.B. Skrifvars, B. Varghese, M.J. Parr — 2012-01-27

Abstract: Background: There are few data comparing outcome and the utility of severity of illness scoring systems following intensive care after out-of-hospital (OHCA), in-hospital (IHCA) and intensive care unit (ICUCA) cardiac arrest. We investigated survival, factors associated with survival and the correlation and accuracy of general and specific scoring systems, including the Apache III score and the OHCA score in OHCA, IHCA and ICUCA patients.Material and methods: Prospective analysis of data on all cardiac arrest patients treated in a tertiary hospital between August 1st 2008 and July 30th 2010. Collected data included resuscitation and post-resuscitation care data as defined by the Utstein Guidelines, Apache III on admission and the OHCA score on admission in OHCA and IHCA patients and after the arrest in ICUCA patients. Statistical methods were used to identify factors associated with outcome and the predictive ability and correlation of the aforementioned scores.Results: Of a total of 3931 patients treated in the ICU, 51 were admitted following OHCA, 50 following IHCA and 22 suffered an ICUCA and had sustained return of spontaneous circulation (ROSC). Survival at 30 days was highest among ICUCAs (67%) followed by IHCAs (38%) and OHCAs (29%). Using multivariate analysis delay ROSC was the only independent predictor of survival. The OHCA score performed with moderate accuracy for predicting 30-day mortality (area under the curve 0.77 [0.69–0.86] and was slightly better than the Apache III score 0.71 (0.61–0.80). Using multiple logistic regression the Apache III and the OHCA score were both independent predictors of hospital survival and correlation between these two scores was weak (correlation coefficient of 0.244).Conclusions: Latency to ROSC seems to be the most important determinant of survival in patients following ICU care after a cardiac arrest in this single center trial. The OHCA score and the Apache III score offer moderate predictive accuracy in ICU cardiac arrest patients but correlated weakly with each other. Illness severity adjustment for cardiac arrest patients in ICU should include features of both these scoring systems.

Prediction protocol for neurological outcome for survivors of out-of-hospital cardiac arrest treated with targeted temperature management

2012-01-27

Abstract: Aim: To identify patients who can obtain the full benefit from targeted temperature management (TTM) after out-of-hospital cardiac arrest.Methods: We performed a retrospective observational study of comatose patients treated with TTM after an out-of-hospital cardiac arrest from January 2006 to February 2011. Neurological outcome was evaluated with the Glasgow-Pittsburgh Cerebral Performance category (CPC) at discharge and predictors were determined.Results: Of 66 patients studied, 40 (60.6%) survived to neurologically intact discharge (CPC 1 or 2). According to multivariate analysis, predictors of good neurological outcome included arrest-to-first cardiopulmonary resuscitation attempt interval ≤5min, ventricular fibrillation or ventricular tachycardia in the first monitored rhythm, absence of re-arrest before leaving the emergency department, arrest-to-return of spontaneous circulation interval ≤30min and recovery of pupillary light reflex, which were identifiable in the emergency department. Based on this analysis, we developed a seven-point score (5-R score). If the score was ≥5, it predicted good neurological outcome with a sensitivity of 82.5% (95% confidence interval [CI], 67.2–92.7%) and specificity of 92.3% (95% CI, 74.9–99.1%). The negative predictive value of a score ≥4 was 100% (95% CI, 81.5–100%). Our prediction model was validated internally by a bootstrapping technique.Conclusions: The prediction protocol using the 5-R score was associated with good neurological outcome of patients treated with TTM. Therefore, it could be helpful in clinical decision making on whether to initiate cooling.

Comparison of different video laryngoscopes for emergency intubation in a standardized airway manikin with immobilized cervical spine by experienced anaesthetists. A randomized, controlled crossover trial

2011-12-08

Abstract: Background: The aim of the present study was to evaluate whether different video laryngoscopes (VLs) facilitate endotracheal intubation (ETI) faster or more secure than conventional laryngoscopy in a manikin with immobilized cervical spine.Methods: After local ethics board approval, a standard airway manikin with cervical spine immobilization by means of a standard stiff collar was placed on a trauma stretcher. We compared times until glottic view, ETI, cuff block and first ventilation were achieved, and verified the endotracheal tube position, when using Macintosh laryngoscope, Glidescope Ranger, Storz C-MAC, Ambu Pentax AWS, Airtraq, and McGrath Series5 VLs in randomized order. Wilcoxon signed-rank test and McNemar's test were used for statistical analysis; p<0.05 was considered as significant.Results: Twenty-three anaesthetists (mean age 32.1±4.9 years, mean experience in anaesthesia of 6.9±4.8 years) routinely involved in the management of multitrauma patients participated. The primary study end point, time to first effective ventilation, was achieved fastest when using Macintosh laryngoscope (21.0±7.6s) and was significantly slower with all other devices (Airtraq 33.2±23.9s, p=0.002; Pentax AirwayScope 32.4±14.9s, p=0.001; Storz C-MAC 34.1±23.9s, p<0.001; McGrath Series5 101.7±108.3s, p<0.001; Glidescope Ranger 46.3±59.1s, p=0.001). Overall success rates were highest when using Macintosh, Airtraq and Storz C-MAC devices (100%), and were lower in Ambu Pentax AWS and Glidescope Ranger (87%, p=0.5) and in McGrath Series5 device (72.2%, p=0.063).Conclusion: When used by experienced anaesthesiologists, video laryngoscopes did not facilitate endotracheal intubation in this model with an immobilized cervical spine in a faster or more secure way than conventional laryngoscopy. However, data was gathered in a standardized model and further studies in real trauma patients are desirable to verify our findings.

Do bulb syringes conform to neonatal resuscitation guidelines?

Pradeep Alur, Jonathan Liss, Frank Ferrentino, Dennis M. Super — 2011-12-06

Abstract: Objective: To reduce airway injury secondary to high suction pressures, the American Academy of Pediatrics Neonatal Resuscitation Program (NPR) recommends that suction pressures be less than 100mm Hg. This study was conducted to determine if suction bulbs conform to these recommendations.Study design: In this prospective in vitro study, 25 personnel involved in neonatal resuscitation squeezed a new bulb three times for each of six commercially available bulbs using their delivery suite technique. A calibrated, pneumatic transducer measured the pressure of each squeeze.Results: Only one bulb met the NRP guidelines with none of the participants exceeding 100mm Hg (p<0.001).Conclusions: Only one bulb met the NRP guidelines of generating pressures less than 100mm Hg. This bulb's large size (3oz) may preclude its use in premature infants. Individuals involved in resuscitating newborns need to be aware of the pressures generated to avoid injuring the delicate oral airway.

Novel adhesive glove device (AGD) for active compression–decompression (ACD) CPR results in improved carotid blood flow and coronary perfusion pressure in piglet model of cardiac arrest

2012-01-03

Abstract: Objective: ACD-CPR improves coronary and cerebral perfusion. We developed an adhesive glove device (AGD) and hypothesized that ACD-CPR using an AGD provides better chest decompression resulting in improved carotid blood flow as compared to standard (S)-CPR.Design: Prospective, randomized and controlled animal study.Methods: Sixteen anesthetized and ventilated piglets were randomized after 3min of untreated VF to receive either S-CPR or AGD-ACD-CPR by a PALS certified single rescuer with compressions of 100min−1 and C:V ratio of 30:2. AGD consisted of a modified leather glove exposing the fingers and thumb. A wide Velcro patch was sewn to the palmer aspect of the glove and the counter Velcro patch was adhered to the pig's chest wall. Carotid blood flow was measured using ultrasound. Data (mean±SD) was analyzed using one way ANOVA and unpaired t-test; p-value≤0.05 was considered statistically significant.Results: Right atrial pressure (mmHg) during the decompression phase was lower during AGD-ACD-CPR (−3.32±2.0) when compared to S-CPR (0.86±1.8, p=0.0007). Mean carotid blood flow was 53.2±27.1 (% of baseline blood flow in ml/min) in AGD vs. 19.1±12.5% in S-CPR, p=0.006. Coronary perfusion pressure (CPP, mmHg) was 29.9±5.8 in AGD vs. 22.7±6.9 in S-CPR, p=0.04. There was no significant difference in time to ROSC and number of epinephrine doses.Conclusion: Active chest decompression during CPR using this simple and inexpensive adhesive glove device resulted in significantly better carotid blood flow during the first 2min of CPR.

Comparison of defibrillation efficacy between two pads placements in a pediatric porcine model of cardiac arrest

Giuseppe Ristagno, Tao Yu, Weilun Quan, Gary Freeman, Yongqin Li — 2011-12-26

Abstract: Objective: The placement of defibrillation pads at ideal anatomical sites is one of the major determinants of transthoracic defibrillation success. However, the optimal pads position for ventricular defibrillation is still undetermined. In the present study, we compared the effects of two different pads positions on defibrillation success rate in a pediatric porcine model of cardiac arrest.Methods: Eight domestic male pigs weighing 12–15kg were randomized to receive shocks using either the anterior–posterior (AP) or the anterior–lateral (AL) position with pediatric pads. Ventricular fibrillation (VF) was electrically induced and untreated for 30s. A sequence of randomized biphasic electrical shocks ranging from 10 to 100J was attempted. If the defibrillation failed to terminate VF, a 100J rescuer shock was then delivered. After a recovery interval of 5min, the sequence was repeated for a total of approximately 30 test shocks were attempted for each animal. The dose response curves were constructed and the defibrillation thresholds were compared between groups.Results: The aggregated success rate was 65.6% for AP placement and 43.0% for AL one (p=0.0005) when shock energy was between 10 and 70J. A significantly lower 50% defibrillation threshold was obtained for AP pads placement compared with traditional AL pads position (2.1±0.4J/kg vs. 3.6±0.9J/kg, p=0.041).Conclusion: In this pediatric porcine model of cardiac arrest, the anterior–posterior placement of pediatric pads yielded a higher success rate by lowering defibrillation threshold compared to the anterior–lateral position.

Cardiovascular and microvascular responses to mild hypothermia in an ovine model

2011-12-12

Abstract: Aims: Hypothermia is used for brain protection after resuscitation from cardiac arrest and other forms of brain injury, but its impact on systemic and tissue perfusion has not been well defined. The aim of this study was to evaluate the cardiovascular and microvascular responses to mild therapeutic hypothermia (MTH) in an ovine model.Methods: Seven anaesthetised, mechanically ventilated, invasively monitored sheep were cooled from a baseline temperature of 39–40°C to 34°C using cold intravenous fluids, ice packs and transnasal cooling. After 6h of MTH, sheep were progressively re-warmed to baseline temperature. Positive fluid balance was maintained during the entire study period to avoid hypovolemia. In addition to standard haemodynamic assessment, the sublingual microcirculation was evaluated using sidestream dark-field (SDF) videomicroscopy.Results: MTH was associated with significant decreases in cardiac index and left (LVSWI) and right (RVSWI) ventricular stroke work indexes. There was a downward shift in the relationship between LVSWI and pulmonary artery occlusion pressure during MTH, indicating myocardial depression. During MTH, mixed venous oxygen saturation increased, in association with reduced oxygen consumption, but blood lactate concentrations increased significantly. There was a significant decrease in the proportion and density of small perfused vessels. All variables returned to baseline levels during the re-warming phase.Conclusion: In this large animal model, MTH was associated with decreased ventricular function, oxygen extraction and microvascular flow compared to normothermia. These changes were associated with increased blood lactate levels. These observations suggest that MTH may impair tissue oxygen delivery through maldistribution of capillary flow.

Balanced vs unbalanced crystalloid resuscitation in a near-fatal model of hemorrhagic shock and the effects on renal oxygenation, oxidative stress, and inflammation

Ugur Aksu, Rick Bezemer, Berna Yavuz, Asli Kandil, Cihan Demirci, Can Ince — 2011-12-06

Abstract: Background: The aim of the present study was to test the hypothesis that balanced crystalloid resuscitation would be better for the kidney than unbalanced crystalloid resuscitation in a rat hemorrhagic shock model.Methods: Male Wistar rats were randomly assigned to four groups (n=6/group): (1) time control; (2) hemorrhagic shock control; (3) hemorrhagic shock followed by unbalanced crystalloid resuscitation (0.9% NaCl); and (4) hemorrhagic shock followed by acetate and gluconate-balanced crystalloid resuscitation (Plasma Lyte). We tested the solutions for their effects on renal hemodynamics and microvascular oxygenation, strong-ion difference, systemic and renal markers of inflammation and oxidative stress including glycocalyx degradation as well as their effects on renal function.Results: The main findings of our study were that: (1) both the balanced and unbalanced crystalloid solutions successfully restored the blood pressure, but renal blood flow was only recovered by the balanced solution although this did not lead to improved renal microvascular oxygenation; (2) while unbalanced crystalloid resuscitation induced hyperchloremia and worsened metabolic acidosis in hemorrhaged rats, balanced crystalloid resuscitation prevented hyperchloremia, restored the acid–base balance, and preserved the anion gap and strong ion difference in these animals; (3) in addition balanced crystalloid resuscitation significantly improved renal oxygen consumption (increased VO2, decreased ); and (4) however neither balanced nor unbalanced crystalloid resuscitation could normalize systemic inflammation or oxidative stress. Functional immunohistochemistry biomarkers showed improvement in L-FABP in favor of balanced solutions in comparison to the hemorrhagic group although no such benefit was seen for renal tubular injury (measured by NGAL) by giving either unbalanced or balanced solutions.Conclusions: Although balanced crystalloid resuscitation seems superior to balanced crystalloid resuscitation in protecting the kidney after hemorrhagic shock and is certainly better than not applying fluid resuscitation, these solutions were not able to correct systemic inflammation or oxidative stress associated with hemorrhagic shock.

Mechanisms of the beneficial effect of NHE1 inhibitor in traumatic hemorrhage: Inhibition of inflammatory pathways

Dongmei Wu, Jiansong Qi — 2011-12-07

Abstract: This study evaluated the effects of sodium-hydrogen exchanger (NHE1) inhibition on enhancing fluid resuscitation outcomes in traumatic hemorrhagic shock, and examined the mechanisms related to NHE1 inhibitor-induced protection and recovery from hemorrhagic shock. Traumatic hemorrhage was modeled in anesthetized pigs by producing tibia fractures followed by hemorrhage of 25ml/kg for 20min, and then a 4mm hepatic arterial tear with surgical repair after 20min. Animals then underwent low volume fluid resuscitation with either hextend (n=6) or 3mg/kg BIIB513 (NHE1 inhibitor)+hextend (n=6). The experiment was terminated 6h after the beginning of resuscitation. In association with traumatic hemorrhagic shock, there was a decrease in cardiac index, stimulation of the inflammatory response, myocardial, liver and kidney injury. The administration of the NHE1 inhibitor at the time of resuscitation attenuated shock-resuscitation-induced myocardial hypercontracture and resulted in a significant increase in stroke volume index, compared to vehicle-treated controls. NHE1 inhibition also reduced the inflammatory response, and lessened myocardial, liver and kidney injury. In addition, NHE1 inhibition reduced NF-κB activation and iNOS expression, and attenuated of ERK1/2 phosphorylation. Results from the present study indicate that NHE1 inhibition prevents multiple organ injury by attenuating shock-resuscitation-induced myocardial hypercontracture and by inhibiting NF-κB activation and neutrophil infiltration, reducing iNOS expression and ERK1/2 phosphorylation, thereby, reducing systemic inflammation and thus multi-organ injury.

Timing and teamwork—An observational pilot study of patients referred to a Rapid Response Team with the aim of identifying factors amenable to re-design of a Rapid Response System

Emma Peebles, Christian P. Subbe, Paul Hughes, Les Gemmell — 2012-01-03

Abstract: Background: Rapid Response Teams aim to accelerate recognition and treatment of acutely unwell patients. Delays in delivery might undermine efficiency of the intervention. Our understanding of the causes of these delays is, as yet, incomplete.Aim: To identify modifiable causes of delays in the treatment of critically ill patients outside intensive care with a focus on factors amenable to system design.Methods: Review of care records and direct observation with process mapping of care delivered to 17 acutely unwell patients attended by a Rapid Response Team in a District General Hospital in the United Kingdom. Delays were defined as processes with no added value for patient care.Results: Essential diagnostic and therapeutic procedures accounted for only 31% of time of care processes. Causes for delays could be classified into themes as (1) delays in call-out of the Rapid Response Team, (2) problems with team cohesion including poor communication and team efficiency and (3) lack of resources including lack of first line antibiotics, essential equipment, experienced staff and critical care beds.Conclusion: We identified a number of potentially modifiable causes for delays in care of acutely ill patients. Improved process design could include automated call-outs, a dedicated kit for emergency treatment in relevant clinical areas, increased usage of standard operating procedures and staff training using crew resource management techniques.

Concerns about safety of the AutoPulse use in treatment of pulmonary embolism

Anatolij Truhlar, Petr Hejna, Lenka Zatopkova, Roman Skulec, Vladimir Cerny — 2012-02-29

We would like to report two subsequent cases of massive intra-abdominal bleeding that occured during use of an AutoPulse (ZOLL Medical Corp., Chelmsford, MA, USA) in young women treated for pulmonary embolism. We hypothesize that the liver rupture found in both cases might have been caused by repeated circumferential chest compressions by the load-distributing band in the area of completely blocked pulmonary circulation. Pulsating impacts of blood returning from the right ventricle backwards via inferior vena cava may exceed strength of the liver tissue, and cause extensive subcapsular haematomas, which happened to both patients. Subsequent heparinization and thrombolysis led to their exsanguination described as the primary cause of death during autopsy.

Reply to Letter: Concerns about safety of the AutoPulse use in the treatment of pulmonary embolism

Ulrich Herken — 2012-02-29

We would like to thank Dr. Truhlar and his colleagues for reporting these two cases. We fully agree with Dr. Truhlar et al. in their recommendation of early ultrasound examinations in patients heparinized after resuscitation or who have received a thrombolytic agent to rule out intra-abdominal bleeding. The International Liaison Committee on Resuscitation 2010 Worksheet on the question whether “CPR is Safe for Victims” reviewed 100 case reports and case series containing injuries related to primarily manual CPR which included reports similar to the injuries reported in the letter. The Worksheet also recommends that “patients exhibiting hemodynamic or other instability after resuscitation should be reassessed and reevaluated for resuscitation related injuries” as do the authors.

Minimal data set for dispatch centre

Fabrice Dami — 2012-03-05

I could not agree more with Castrén et al. on the fact that dispatching needs a minimal data set so comparison and benchmarking will finally be possible. A frame work for uniform reporting should be accessible to all different type of dispatch (MPDS and other systems).

Reply to Letter: Creation of a minimal data set for dispatching

Maaret Castrén, Katarina Bohm — 2012-03-05

Thank you for your interest in our paper. We fully agree that there are many conditions where the dispatcher should give instructions to the caller. However, the purpose of our paper was to develop the Utstein reporting system for OHCA further. This is why we concentrated only on CPR instructions by the dispatcher. We are studying also other instructions and will send in papers on those as soon as we finish our studies on them.

iGel supraglottic airway use during hospital cardiopulmonary resuscitation

Christopher Larkin, Ben King, Alex D’Agapeyeff, David Gabbott — 2012-03-05

We would like to report our first 100 uses of the iGel supraglottic airway device (Intersurgical Ltd, Wokingham, UK) as part of airway management during hospital based Cardiopulmonary Resuscitation (CPR). The ERC and RC(UK) recommend supraglottic airway control during CPR in circumstances where tracheal intubation is not possible or not within the competency of individuals managing the patient's airway.

Verification of endotracheal tube placement using ultrasound during emergent intubation of a preterm infant

2012-03-05

Endotracheal tube (ET) verification in newborns is usually achieved primarily by direct visualization of the ET passing through the vocal cords by direct laryngoscopy. This is the preferred method by most experienced neonatologists. However, there is evidence indicating that incidental oesophageal intubation is frequent leading to potential serious harm for the baby so a secondary verification method may be necessary. As clinical signs such as auscultation alone may be inaccurate in the preterm, an end tidal carbon dioxide (ETCO2) detector is usually recommended. However, in the setting of low or absent pulmonary blood flow such as during resuscitation or severe hypotension capnography may yield false negative results. Ultrasound is an alternative and complementary method for ET verification shown to be at least as rapid and accurate as capnography for emergent intubation in children and adults. Here we communicate its use in a very low birth weight preterm infant and illustrate the technique. A 31 week gestation and 1.410g 5-days old female baby was being treated for severe sepsis and necrotizing enterocolitis in our NICU. He was on high ventilatory support (Peak pressure 27mmHg, PEEP 7mmHg, FiO2 60%) because of respiratory failure needing surfactant replacement. He suffered an accidental extubation with rapid loss of lung recruitment, severe desaturation (Sat 70%), bradycardia and hypotension that did not respond to bag mask ventilation. She was reintubated with a 2.5mm uncuffed tube without improvement (Sat 75%). Capnography was not readily available and we decided to check ET location by ultrasound. We used an 8-Hz microconvex transducer in the longitudinal and transversal plane above the suprasternal notch. We were able to clearly see the ET within the trachea immediately posterior to tracheal anterior rings (). We then added a PEEP valve to the bag and ventilated the baby with an increasing level of PEEP (max. 8mmHg) oxygen saturation slowly raised in two minutes and the baby stabilized.

Pacemaker lead failure masquerading as ventricular fibrillation

Andrew J. Brenyo, David T. Huang — 2012-02-29

We report a case of atrial flutter mistaken for ventricular fibrillation after occult acute pacemaker lead failure in a 78-year-old man with an episode of syncope after completion of a bowel preparation for colonoscopy. His wife heard him go to the restroom and then fall to the floor where she then found him unconscious. Emergency medical services were contacted and upon their arrival he was found to be alert and oriented without lasting effects from his event. He has a history of coronary artery disease and a dual chamber pacemaker placed for complete heart block. Initial evaluation in the emergency department revealed a well appearing elderly male in no acute distress. His ECG at triage is displayed in . Subsequently he experienced a pulseless arrest with the rhythm displayed in .

Survey of pre-hospital therapeutic hypothermia use in France

Youri Yordanov, Gérald Kierzek, Loic Huet, Jean-Louis Pourriat — 2012-03-14

Fifty thousand out-of-hospital cardiac arrests (OHCA) occur in France each year. As part of post-resuscitation care, therapeutic hypothermia (TH) is recommended for comatose OHCA survivors with a shockable rhythm. Recent studies show that cooling can be initiated in the prehospital setting. We have evaluated the implementation of prehospital TH by the French emergency medical service system (EMS), the cooling methods used, and barriers to spread. In February and March 2010, we conducted a telephone survey of the 105 regional EMS (SAMU: Service D’Aide Médicale Urgente), using a web-based questionnaire.

Complication of intraosseous administration of systemic fibrinolysis for a massive pulmonary embolism with cardiac arrest

2012-03-05

We managed a 53-year-old man for suspected acute respiratory failure. Accessing a peripheral vein was very difficult. Before insertion of venous access, the patient developed ventricular fibrillation (VF) cardiac arrest. We started cardiopulmonary resuscitation (CPR) with chest compressions. An intraosseous (IO) catheter (EZ-IO®, Vidacare®) was inserted into the proximal tibia. After 30min of resuscitation, including injection of adrenaline, he remained in asystole. Echocardiography showed marked right ventricular dilatation and a collapsed left ventricle. We suspected massive pulmonary embolism (MPE) and gave thrombolysis (Acteplase 0.6mgkg−1). Five minutes later, sinus rhythm was restored. Femoral venous access was inserted and the IO catheter was removed. The patient was treated successfully in the intensive care unit (ICU) for post cardiac arrest syndrome with multi-organ failure. He had few residual neurological sequelae. A large extensive necrosis of the anteromedial side of the right leg appeared in the IO insertion area () 48h later. Medical treatment failed, thus surgical excision was performed followed by vacuum-assisted closure. After 5 weeks in the ICU, vacuum therapy was pursued for 3 weeks in the dermatology department with repetitive surgical dressing. Ulceration persisted on the whole anteromedial side of the right leg with direct exposure of bone. The computed tomography (CT) angiography revealed the large tissue defect without abscess or an osteolytic lesion. Surgical grafting was successfully performed 9 weeks later.

Cardiac arrest in a 35-year-old pregnant woman with sarcoidosis

Christian Wallmüller, Hans Domanovits, Florian B. Mayr, Anton N. Laggner — 2012-02-27

We report the case of a 35-year-old pregnant woman (32weeks of gestation) with a history of pulmonary sarcoidosis with suspected cardiac involvement, who suffered a cardiac arrest at home. When the emergency medical service (EMS) arrived, the patient's husband and her sister-in-law, who happened to be a registered nurse, were performing basic life support. Despite 20min of advanced life support including application of 7 shocks, orotracheal intubation, and administration of 6mg adrenaline and 300mg amiodarone on the scene, the patient remained pulseless and was transferred to our department under ongoing CPR.