Resuscitation

Timing of drug administration during CPR and the role of simulation

Joyce Yeung, Gavin D. Perkins — 2010-03-01

The role of drugs in cardiopulmonary resuscitation (CPR) remains unclear. To date no randomised controlled study has demonstrated that the routine use of any vasopressor at any stage during cardiac arrest increases the rate of neurologically intact survival to hospital discharge in humans. The favourable outcome of initial return of spontaneous circulation (ROSC) and increased survival seen with vasopressors in animal studies have not been consistently shown in human studies. The large prospective observational study of more than 10000 cardiac arrests in Sweden found the use of adrenaline was an independent predictor of poor outcomes. The introduction of advanced life support (ALS) trained paramedics in the OPALS study failed to change survival rates in over 4000 cardiac arrest victims. Recently, the Intravenous Drug Administration During Out-of-Hospital Cardiac Arrest study randomised 851 patients to receive ALS with intravenous drug administration or ALS with no access to intravenous drug administration. The study reported an increase in the rate of ROSC, however, this was not sustained until to hospital discharge.

A traumatic swollen tongue

Bruce M. Lo, Brian H. Campbell — 2010-01-13

A 51-year-old male presented with tongue pain and swelling after a tonic–clonic seizure caused by alcohol withdrawal. The patient reported biting his tongue during the seizure and complained of progressive swelling to the tongue, difficulty swallowing saliva, and difficulty breathing. He was not taking any medications including anticoagulants and had a normal complete blood count and coagulation studies. He reported daily alcohol use and one previous alcohol withdrawal seizure 10 years ago. On examination there was a haematoma and swelling of the submandibular area with elevation of the tongue (). The patient was tiring, finding breathing difficult and was unable to swallow his own secretions. He therefore had an awake fibre-optic nasotracheal intubation for airway protection. A computed tomography scan of the neck showed severe oedema of the posterior oropharynx (). Subsequent treatment included steroids and the swelling resolved after 4 days. The patient's trachea was extubated without difficulty and he was discharged home a week later.

Dominique-Jean Larrey: The effects of therapeutic hypothermia and the first ambulance

Salomon Jasqui Remba, Joseph Varon, Alma Rivera, George L. Sternbach — 2009-12-28

Abstract: The fields of emergency medicine and resuscitation are indebted to the Baron Dominique-Jean Larrey (1766–1842) for significant advances in patient care. Larrey was a great surgeon who served in the French army during Napoleon's rule. He developed one of the first ambulance services, utilized positive pressure ventilation, and introduced hypothermia as a form of therapy. He dedicated his professional life to improving the care of wounded soldiers on the battlefield. Larrey coined the term “Triage” to allocate resources to those most in need of emergent care. Today, many of his techniques still prevail in modern medicine.

Gastric perforation after cardiopulmonary resuscitation: Review of the literature

Isabelle Spoormans, Kim Van Hoorenbeeck, Lee Balliu, Philippe G. Jorens — 2010-01-11

Abstract: The risk of complications of cardiopulmonary resuscitation (CPR) does not outweigh the benefit of a successful restoration of a spontaneous circulation. Despite the frequent occurrence of gastric distension (caused by air entering the stomach because of too forceful and/or too quick rescue breathing), there are few reports of massive gastric distension causing gastric rupture and pneumoperitoneum after CPR. We reviewed all 67 case reports of gastric perforation that have been reported after CPR. Although uncommon, this review stresses the need to consider this potentially lethal complication after initial successful resuscitation.

The value of symptoms and signs in the emergent diagnosis of acute coronary syndromes

2009-12-28

Abstract: Objective: Patient history and physical examination are widely accepted as cornerstones of diagnosis in modern medicine. We aimed to assess the value of individual historical and examination findings for diagnosing acute myocardial infarction (AMI) and predicting adverse cardiac events in undifferentiated Emergency Department (ED) patients with chest pain.Methods: We prospectively recruited patients presenting to the ED with suspected cardiac chest pain. Clinical features were recorded using a custom-designed report form. All patients were followed up for the diagnosis of AMI and the occurrence of adverse events (death, AMI or urgent revascularization) within 6 months.Results: AMI was diagnosed in 148 (18.6%) of the 796 patients recruited. Following adjustment for age, sex and ECG changes, the following characteristics made AMI more likely (adjusted odds ratio, 95% confidence intervals): pain radiating to the right arm (2.23, 1.24–4.00), both arms (2.69, 1.36–5.36), vomiting (3.50, 1.81–6.77), central chest pain (3.29, 1.94–5.61) and sweating observed (5.18, 3.02–8.86). Pain in the left anterior chest made AMI significantly less likely (0.25, 0.14–0.46). The presence of rest pain (0.67, 0.41–1.10) or pain radiating to the left arm (1.36, 0.89–2.09) did not significantly alter the probability of AMI.Conclusions: Our results challenge many widely held assertions about the value of individual symptoms and signs in ED patients with suspected acute coronary syndromes. Several ‘atypical’ symptoms actually render AMI more likely, whereas many ‘typical’ symptoms that are often considered to identify high-risk populations have no diagnostic value.

Delaying a shock after takeover from the automated external defibrillator by paramedics is associated with decreased survival

2009-12-21

Abstract: Introduction: The purpose of this study was to investigate whether the takeover by Advanced Life Support [ALS] trained ambulance paramedics from rescuers using an automated external defibrillator [AED] delays shocks and if this delay is associated with decreased survival after out-of-hospital cardiac arrest [OHCA].Methods: We analyzed continuous ECG recordings of LIFEPAK AEDs and associated manual defibrillator recordings of OHCA of presumed cardiac cause, prospectively collected from July 2005 to July 2009. The primary outcome measure was survival to discharge. Among 693 patients treated with AEDs, 110 had a shockable initial rhythm and a shockable rhythm during ALS takeover. We measured the time interval between the expected shock if the AED would remain attached to the patient and the first observed shock given by the manual defibrillator [shock timing].Results: Survival was 62% (13/21) if the shock was given early ( 150s. The OR for trend was 0.41, 95% CI=0.25–0.71; P=0.001. The association between shock timing and survival was significant for patients with more than 150s shock delay (OR=0.19; 95% CI=0.04–0.71; P=0.02) or for trend in shock timing (0.42, 95% CI=0.20–0.84; P=0.02) after multivariable adjustment for prognostic factors age and slope of ventricular fibrillation.Conclusions: ALS takeover delays the next shock delivery in almost two-third of cases. This delay is associated with decreased survival.

Performance of chest compressions by laypersons during the Public Access Defibrillation Trial

Thomas D. Rea, Ronald E. Stickney, Alidene Doherty, Paula Lank — 2010-01-04

Abstract: Background: Increasing evidence indicates that health professionals often may not achieve guideline standards for cardiopulmonary resuscitation (CPR). Little is known about layperson CPR performance.Methods: The investigation was a retrospective cohort study of cardiac arrest patients treated by layperson CPR and one model of automated external defibrillator (AED) as part of the Public Access Defibrillation Trial (n=26). CPR was measured using software that integrates the event log, ECG signal, and thoracic impedance signal. We assessed chest compression fraction (proportion of attempted resuscitation spent performing chest compressions), prompted compression fraction (proportion of attempted resuscitation spent performing compressions during AED-prompted periods), compression rate, and compressions per minute.Results: Of the 26 cases, 13 presented with ventricular fibrillation and 13 with nonshockable rhythms. Overall, during the period when patients did not have spontaneous circulation, the median chest compression fraction was 34% (IQR 17–48%), median prompted chest compression fraction was 49% (IQR 30–66%), and the median chest compression rate was 96/min (IQR 90–110/min). Taken together, the median chest compression delivered per minute among all arrests was 29 (IQR 20–42). CPR characteristics differed according to initial rhythm: median chest compression per minute was 20 (IQR 13–29) among ventricular fibrillation and 42 (IQR 28–47) among nonshockable rhythms (p=0.003).Conclusions: In this study of trained laypersons, CPR varied substantially and often did not achieve guideline parameters. The findings suggest a need to improve CPR training, consider changes to CPR protocols, and/or improve the AED–rescuer interface.

Detrended fluctuation analysis predicts successful defibrillation for out-of-hospital ventricular fibrillation cardiac arrest

2010-01-13

Abstract: Aims: Repeated failed shocks for ventricular fibrillation (VF) in out-of-hospital cardiac arrest (OOHCA) can worsen the outcome. It is very important to rapidly distinguish between early and late VF. We hypothesised that VF waveform analysis based on detrended fluctuation analysis (DFA) can help predict successful defibrillation.Methods: Electrocardiogram (ECG) recordings of VF signals from automated external defibrillators (AEDs) were obtained for subjects with OOHCA in Taipei city. To examine the time effect on DFA, we also analysed VF signals in subjects who experienced sudden cardiac death during Holter study from PhysioNet, a publicly accessible database. Waveform parameters including root-mean-squared (RMS) amplitude, mean amplitude, amplitude spectrum analysis (AMSA), frequency analysis as well as fractal measurements including scaling exponent (SE) and DFA were calculated. A defibrillation was regarded as successful when VF was converted to an organised rhythm within 5s after each defibrillation.Results: A total of 155 OOHCA subjects (37 successful and 118 unsuccessful defibrillations) with VF were included for analysis. Among the VF waveform parameters, only AMSA (7.61±3.30 vs. 6.30±3.13, P=0.028) and DFAα2 (0.38±0.24 vs. 0.49±0.24, P=0.013) showed significant difference between subjects with successful and unsuccessful defibrillation. The area under the curves (AUCs) for AMSA and DFAα2 was 0.63 (95% confidence interval (CI)=0.52–0.73) and 0.65 (95% CI=0.54–0.75), respectively. Among the waveform parameters, only DFAα2, SE and dominant frequency showed significant time effect.Conclusions: The VF waveform analysis based on DFA could help predict first-shock defibrillation success in patients with OOHCA. The clinical utility of the approach deserves further investigation.

Pre-resuscitation factors associated with mortality in 49,130 cases of in-hospital cardiac arrest: A report from the National Registry for Cardiopulmonary Resuscitation

Gregory Luke Larkin, Wayne S. Copes, Brian H. Nathanson, William Kaye — 2010-01-04

Abstract: Aim: To evaluate key pre-arrest factors and their collective ability to predict post-cardiopulmonary arrest mortality. CPR is often initiated indiscriminately after in-hospital cardiopulmonary arrest. Improved understanding of pre-arrest factors associated with mortality may inform advance care planning.Methods: A cohort of 49,130 adults who experienced pulseless cardiopulmonary arrest from January 2000 to September 2004 was obtained from 366 US hospitals participating in the National Registry for Cardiopulmonary Resuscitation (NRCPR). Logistic regression with bootstrapping was used to model in-hospital mortality, which included those discharged in unfavorable and severely worsened neurologic state (Cerebral Performance Category ≥3).Results: Overall in-hospital mortality was 84.1%. Advanced age, black race, non-cardiac, non-surgical illness category, pre-existing malignancy, acute stroke, trauma, septicemia, hepatic insufficiency, general floor or Emergency Department location, and pre-arrest use of vasopressors or assisted/mechanical ventilation were independently predictive of in-hospital mortality. Retained peri-arrest factors including cardiac monitoring, and shockable initial pulseless rhythms, were strongly associated with survival. The validation model's AUROC curve (0.77) revealed fair performance.Conclusions: Predictive pre-resuscitation factors may supplement patient-specific information available at bedside to assist in revising resuscitation plans during the patient's hospitalization.

Critical incidents related to cardiac arrests reported to the Danish Patient Safety Database

Peter Oluf Andersen, Rikke Maaløe, Henning B. Andersen — 2009-12-21

Abstract: Background: Critical incident reports can identify areas for improvement in resuscitation practice. The Danish Patient Safety Database is a mandatory reporting system and receives critical incident reports submitted by hospital personnel. The aim of this study is to identify, analyse and categorize critical incidents related to cardiac arrests reported to the Danish Patient Safety Database.Methods: The search terms “cardiac arrest” and “resuscitation” were used to identify reports in the Danish Patient Safety Database. Identified critical incidents were then classified into categories.Results: One hundred and seven reports describing 122 separate incidents were identified and classified into incidents related to: alerting the resuscitation team (n=32; 26%), human performance (n=22; 18%), equipment failure (n=19; 16%), resuscitation equipment not available (n=13; 11%), physical environment (n=14; 11%), insufficient monitoring (n=14; 11%), and medication error (n=8; 7%).Conclusion: Critical incidents related to cardiac arrest occur due to logistical, technical, teamworking and knowledge problems. These findings should be considered when planning education and implementing resuscitation practice.

Capnography and chest-wall impedance algorithms for ventilation detection during cardiopulmonary resuscitation

2009-12-28

Abstract: Objective: Hyperventilation is both common and detrimental during cardiopulmonary resuscitation (CPR). Chest-wall impedance algorithms have been developed to detect ventilations during CPR. However, impedance signals are challenged by noise artifact from multiple sources, including chest compressions. Capnography has been proposed as an alternate method to measure ventilations. We sought to assess and compare the adequacy of these two approaches.Methods: Continuous chest-wall impedance and capnography were recorded during consecutive in-hospital cardiac arrests. Algorithms utilizing each of these data sources were compared to a manually determined “gold standard” reference ventilation rate. In addition, a combination algorithm, which utilized the highest of the impedance or capnography values in any given minute, was similarly evaluated.Results: Data were collected from 37 cardiac arrests, yielding 438min of data with continuous chest compressions and concurrent recording of impedance and capnography. The manually calculated mean ventilation rate was 13.3±4.3/min. In comparison, the defibrillator's impedance-based algorithm yielded an average rate of 11.3±4.4/min (p=0.0001) while the capnography rate was 11.7±3.7/min (p=0.0009). There was no significant difference in sensitivity and positive predictive value between the two methods. The combination algorithm rate was 12.4±3.5/min (p=0.02), which yielded the highest fraction of minutes with respiratory rates within 2/min of the reference. The impedance signal was uninterpretable 19.5% of the time, compared with 9.7% for capnography. However, the signals were only simultaneously non-interpretable 0.8% of the time.Conclusions: Both the impedance and capnography-based algorithms underestimated the ventilation rate. Reliable ventilation rate determination may require a novel combination of multiple algorithms during resuscitation.

Out-of-hospital airway management by paramedics and emergency physicians using laryngeal tubes

2009-12-14

Abstract: Concept: Endotracheal intubation (ETI) is considered to be the gold standard of prehospital airway management. However, ETI requires substantial technical skills and ongoing experience. Because failed prehospital ETI is common and associated with a higher mortality, reliable airway devices are needed to be used by rescuers less experienced in ETI. We prospectively evaluated the feasibility of laryngeal tubes used by paramedics and emergency physicians for out-of-hospital airway management.Material and methods: During a 24-month period, all cases of prehospital use of the laryngeal tube disposable (LT-D) and laryngeal tube suction disposable (LTS-D) within five operational areas of emergency medical services were recorded by a standardised questionnaire. We determined indications for laryngeal tube use, placement success, number of placement attempts, placement time and personal level of experience.Results: Of 157 prehospital intubation attempts with the LT-D/LTS-D, 152 (96.8%) were successfully performed by paramedics (n=70) or emergency physicians (n=87). The device was used as initial airway (n=87) or rescue device after failed ETI (n=70). The placement time was ≤45s (n=120), 46–90s (n=20) and >90s (n=7). In five cases the time needed was not specified. The number of placement attempts was one (n=123), two (n=25), three (n=2) and more than three (n=2). The majority of users (61.1%) were relative novices with no more than five previous laryngeal tube placements.Conclusion: The LT-D/LTS-D represents a reliable tool for prehospital airway management in the hands of both paramedics and emergency physicians. It can be used as an initial tool to secure the airway until ETI is prepared, as a definitive airway by rescuers less experienced with ETI or as a rescue device when ETI has failed.

Delivery room resuscitation of near-term infants: Role of the laryngeal mask airway

2009-12-21

Abstract: Aim: This observational study aims to describe: (1) the use of positive pressure ventilation (PPV) for resuscitation in the delivery room among newly born near-term infants; (2) the methods used for PPV resuscitation [e.g., bag–facial mask (BFM), laryngeal mask airway (LMA), endotracheal tube (ETT)]; and (3) the association of each device with short-term neonatal outcomes.Methods: We identified near-term (34 0/7–36 6/7 weeks) infants delivered at the Padua University Hospital (Padua, Italy) during the years 2002–2006. The mode of delivery, gestational age, birth weight, Apgar scores, methods of resuscitation and respiratory outcome after NICU admission were analysed.Results: During the 5-year study period, 921 (4.9%) near-term infants were identified from a total of 18,641 live births. PPV was provided in the delivery room to 86 (9.3%) of these infants. Among them, 36 (41.8%) were managed by LMA, 34 (39.5%) by BFM and 16 (18.6%) by ETT. Thirty-four (39.5%) resuscitated near-term infants were admitted to the Neonatal Intensive Care Unit (NICU): 15 (44.1%) after BFM, 12 (75%) after ETT and seven (19.4%) after LMA. Resuscitation with an ETT was associated with an increased rate of respiratory distress syndrome when compared with either BFM or LMA. Resuscitation with an LMA was associated with a lower rate of NICU admission and shorter length of stay when compared with either BFM or ETT.Conclusion: The LMA is an effective device for primary airway management of near-term infants and for secondary airway management among near-term infants failing BFM or ETT resuscitation.

Reliability and validity of a scoring instrument for clinical performance during Pediatric Advanced Life Support simulation scenarios

Aaron Donoghue, Akira Nishisaki, Robert Sutton, Roberta Hales, John Boulet — 2010-01-04

Abstract: Aim: To assess the reliability and validity of scoring instruments designed to measure clinical performance during simulated resuscitations requiring the use of Pediatric Advanced Life Support (PALS) algorithms.Methods: Pediatric residents were invited to participate in an educational trial involving simulated resuscitations that employ PALS algorithms. Each subject participated in a session comprised of four scenarios (asystole, dysrhythmia, respiratory arrest, shock). Video-recorded sessions were independently reviewed and scored by four raters using instruments designed to measure performance in terms of timing, sequence, and quality. Validity was assessed by two-factor analysis of variance with postgraduate year (PGY-1 versus PGY-2) as an independent variable. Reliability was assessed by calculation of overall interrater reliability (IRR) as well as a generalizability study to estimate variance components of individual measurement facets (scenarios, raters) and associated interactions.Results: 20 subjects were scored by four raters. Based on a two-factor ANOVA, PGY-2s outperformed PGY-1s (p<0.05); significant differences in difficulty existed between the four scenarios, with dysrhythmia scores being the lowest. Overall IRR was high (0.81) and most variance could be attributed to subject (17%), scenario (13%), and the interaction between subject and scenario (52%); variance attributable to rater was minimal (1.4%).Conclusions: The instruments assessed in this study measure clinical performance during PALS scenarios in a reliable and valid manner. Measurement error could be minimized further through the use of additional scenarios but additional raters, for a given scenario, would not improve reliability. Further studies should assess validity of measurement with respect to actual clinical performance during resuscitations.

Can early serum levels of S100B protein predict the prognosis of patients with out-of-hospital cardiac arrest?

Kyoung Jun Song, Sang Do Shin, Marcus Eng Hock Ong, Joong Sik Jeong — 2010-01-04

Abstract: Objective: This study aims to know if the level of S100B protein at the initiation of cardiopulmonary resuscitation (CPR) and immediately after return of spontaneous circulation (ROSC) can predict clinical outcome.Materials and methods: A prospective observational study from December 2004 to October 2006 was conducted in an urban tertiary hospital emergency department. Clinical demographics for out-of-hospital cardiac arrest patients were collected based on the Utstein style. Outcomes collected included ROSC for 20min, survival to admission, survival and Glasgow Outcome Scale (GOS) at 1 month. S100B protein was measured twice before starting CPR (first S100B) and immediately after ROSC (second S100B). We investigated the association between S100B protein levels and clinical outcomes using a multivariate logistic regression model.Results: A total of 151 patients were included (age: 60.2±16.8 years, male: 64.2%). Of these, 60 (39.7%) had ROSC and 46 (30.5%) survived to admission. After 1 month, 12 (8.0%) survived and only three patients showed good GOS (≥4 points). The S100B levels were not different for ROSC, survival to admission and 1-month survival between survivors and non-survivors (p>0.05, first and second S100 B level). For the witnessed out-of-hospital cardiac arrest (OHCA) group (N=87), only the first S100B (1.22±0.85μgl−1 vs. 3.91±4.25μgl−1, p<0.001) showed significant difference for 1-month survival between survivors and non-survivors. The first S100B showed significant association with survival to emergency department (ED) but not 1-month survival (adjusted odds ratio (OR)=0.905, 95% confidence interval=0.821–0.998).Conclusion: Higher levels of S100B at start of CPR were significantly associated with lower survival to admission, and not for 1-month survival.

Increase in pre-shock pause caused by drug administration before defibrillation: An observational, full-scale simulation study

Christian Bjerre Høyer, Erika F. Christensen, Berit Eika — 2010-01-18

Abstract: Background: The importance of circulation during cardiopulmonary resuscitation has led to efforts to decrease time without chest compressions (“no-flow time”). The no-flow time from the interruption of chest compressions until defibrillation is referred to as the “pre-shock pause”. A shorter pre-shock pause increases the chance of successful defibrillation. It is unclear whether drug administration affects the length of the pre-shock pause. Our study compares pre-shock pause with and without drug administration in a full-scale simulation.Methods: This was an observational study in an ambulance including 72 junior physicians and a cardiac arrest scenario. Data were extracted by reviewing video recordings of the resuscitation. Sequences including defibrillation and/or drug administration were identified and assigned to one out of four categories: Defibrillation only (DC-only) and drug administration just prior to defibrillation (Drug+DC) for which the pre-shock pause was calculated, and drug administration alone (Drug-only) for which pre-drug time was calculated.Results: DC-only sequences were identified in 68/72 simulations, Drug+DC in 24/72, and Drug-only in 33/72. Median pre-shock pauses were 18s (DC-only) and 32 (Drug+DC), and median pre-drug pause 6. The variation between pauses was statistically significant (p≪0.001). DC-only and Drug+DC sequences was found in 22/72 simulations. A statistically significant difference of 8s was found between the median pre-shock pauses: 17s (DC-only) and 25 (Drug+DC) (p≪0.001). For un-paired observations, the pre-shock pause increased with 78% and for paired observations 47%.Conclusions: Drug administration prior to defibrillation was associated with significant increases in pre-shock pauses in this full-scale simulation study.

Distribution of pre-course BLS/AED manuals does not influence skill acquisition and retention in lay rescuers: A randomised study

2010-01-14

Abstract: Aim: The present study aims to investigate whether the distribution of the Basic Life Support and Automated External Defibrillation (BLS/AED) manual, 4 weeks prior to the course, has an effect on skill acquisition, theoretical knowledge and skill retention, compared with courses where manuals were not distributed.Methods: A total of 303 laypeople were included in the present study. The courses were randomised with sealed envelopes in 12 courses, where manuals were distributed to participants (group A) and in 12 courses, where manuals were not distributed to participants (group B). The participants were formally evaluated at the end of the course, and at 1, 3 and 6 months after each course. The evaluation procedure was the same at all time intervals and consisted of two distinct parts: a written test and a simulated cardiac arrest scenario.Results: No significant difference was observed between the two groups in skill acquisition at the time of initial training. Furthermore, there was no significant difference between the groups in performing BLS/AED skills at 1, 3 and 6 months after initial training. Theoretical knowledge in either group at the specified time intervals did not exhibit any significant difference. Significant deterioration of skills was observed in both groups between initial training and at 1 month after the course, as well as between the first and third month after the course.Conclusion: The present study shows that distribution of BLS/AED manuals 1 month prior to the course has no effect on theoretical knowledge, skill acquisition and skill retention in laypeople.

Perfluorocarbon induced intra-arrest hypothermia does not improve survival in a swine model of asphyxial cardiac arrest

Ali S. Albaghdadi, Leonard A. Brooks, Andrew M. Pretorius, Richard E. Kerber — 2010-01-04

Abstract: Background: Pulseless electrical activity is an important cause of cardiac arrest. Our purpose was to determine if induction of hypothermia with a cold perfluorocarbon-based total liquid ventilation (TLV) system would improve resuscitation success in a swine model of asphyxial cardiac arrest/PEA.Methods: Twenty swine were randomly assigned to control (C, no ventilation, n=11) or TLV with pre-cooled PFC (n=9) groups. Asphyxia was induced by insertion of a stopper into the endotracheal tube, and continued in both groups until loss of aortic pulsations (LOAP) was reached, defined as a pulse pressure less than 2mmHg. The TLV animals underwent asphyxial arrest for an additional 2min after LOAP, followed by 3min of hypothermia, prior to starting CPR. The C animals underwent 5min of asphyxia beyond LOAP. Both groups then underwent CPR for at least 10min. The endpoint was the resumption of spontaneous circulation maintained for 10min.Results: Seven of 9 animals achieved resumption of spontaneous circulation (ROSC) in the TLV group vs. 5 of 11 in the C group (p=0.2). The mean pulmonary arterial temperature was lower in total liquid ventilation animals starting 4min after induction of hypothermia (TLV 36.3±0.2°C vs. C 38.1±0.2°C, p<0.0001). Arterial was higher in total liquid ventilation animals at 2.5min of CPR (TLV 76±12mmHg vs. C 44±2mmHg; p=0.03).Conclusion: Induction of moderate hypothermia using perfluorocarbon-based total liquid ventilation did not improve ROSC success in this model of asphyxial cardiac arrest.

Rapid cooling of the heart with total liquid ventilation prevents transmural myocardial infarction following prolonged ischemia in rabbits

2010-01-13

Abstract: Study aim: Total liquid ventilation (TLV) with cooled perfluorocarbons has been demonstrated to induce an ultrafast cardioprotective cooling in rabbits. However, it remains unknown whether this technically challenging strategy would be actually more potent than a conventional external cooling after a prolonged ischemia inducing transmural myocardial infarction.Methods: Anesthetized rabbits were randomly submitted to 60min of coronary artery occlusion (CAO) under normothermic conditions (Control group, n=7) or with cooling started at the 5th min of CAO (target left atrial temperature: 32°C). Cooling procedures were either external cooling using cold blankets (EC group, n=7) or ultrafast cooling initiated by 20min of TLV (TLV group, n=6). An additional group underwent a similar ultrafast cooling protocol started at the 20th min of CAO (TLVdelayed group, n=6). After reperfusion, all hypothermic animals were rewarmed and infarct size was assessed after 4h.Results: In the EC group, the target temperature was reached only at 60min of CAO whereas this time-interval was dramatically reduced to 15 and 25min of CAO in TLV and TLVdelayed, respectively. Infarct sizes were significantly reduced in TLV and TLVdelayed but not in EC groups as compared to Control (45±18%, 58±5%, 78±10% and 82±7% of the risk zone, respectively). Similar significant differences were observed for the sizes of the no-reflow zones (15±9%, 23±8%, 49±11% and 58±13% of the risk zone, respectively).Conclusion: Cooling induced by TLV afforded a potent cardioprotection and prevented transmural infarction following prolonged and severe ischemia, even when started later than a surface cooling in rabbits.

Impact of chemical, biological, radiation, and nuclear personal protective equipment on the performance of low- and high-dexterity airway and vascular access skills

Jan Schumacher, Stuart A. Gray, Andrea Brinker — 2010-01-04

We read with great interest the study of Castle and coworkers, investigating the “Impact of Chemical, Biological, Radiation, and Nuclear Personal Protective Equipment on the performance of low- and high-dexterity airway and vascular access skills”.

Reply to Letter: Impact of chemical, biological, radiation, and nuclear personal protective equipment on the performance of low- and high-dexterity airway and vascular access skills

N. Castle, S. Clarke, R. Owen — 2010-01-13

We thank Dr. Schumacher and colleagues for adding to the debate around skill performance whilst wearing CBRN-PPE and congratulate Schumacher et al. on their recent paper. We chose to assess skills performed in the currently issued NHS CBRN-PPE although we accept that other types of suits and different makes of gloves are available. These variations of CBRN-PPE are not currently issued by the Department of Health and are therefore not widely available within the NHS. We accept that this is an important area of research; however any change in the provision of CBRN-PPE will require significant reinvestment.

High levels of neuron-specific enolase after CPR and good clinical outcome

Wolfram Schummer, Claudia Schummer, Jakob Wiegand — 2010-01-14

Recent studies have suggested that neuron-specific enolase (NSE) is a helpful predictor of outcome for initially comatose patients after cardiopulmonary resuscitation (CPR), particularly in the case of poor outcomes. To avoid withdrawal of support in patients who have a plausible chance of recovery, it is essential that such a test has a near zero rate of false positives for determining a poor prognosis.

Torsades de pointes in amitraz poisoning

2009-12-28

A 53-year-old Taiwanese 58kg female attempted suicide by ingesting 500ml of the pesticide amitraz (20% emulsifiable concentration). One hour later, she was found unconscious by her daughter. She was taken to the local hospital where her trachea was intubated and she was commenced on intermittent positive pressure ventilation at 16breaths/min with a FiO2 of 1.0. She underwent gastric lavage. On arrival at our institution, her vital signs were a blood pressure of 102/48mmHg, pulse rate of 53beats/min, body temperature of 34.2°C. Physical examination revealed a Glasgow Coma Scale score of E1VTM1, pupil size of 5mm/5mm with trace light reflex, and irregular heart beats. Laboratory investigations were potassium of 3.4mmol/L (normal: 3.5–5.3), blood sugar 139mg/dl (normal: 70–110), aspartate aminotransferase 74U/l (normal: 0–44), alanine aminotransferase 47U/l (normal: 0–38), and lactate dehydrogenase 275U/l (normal: 120–240). Arterial blood gas was pH 7.432, PaO2 440mmHg, PaCO2 24mmHg, and HCO3− 16.8mmol/l. Other values were normal, including calcium, phosphorus, magnesium, renal function and cardiac enzymes. A 12-lead electrocardiograph showed a marked pronlongation of the QT interval and corrected QT interval with bigeminal ventricular extrasystoles (A). She developed torsades de pointes (TdP) and was immediately given a 150J biphasic shock. She received repeated defibrillation, magnesium sulfate (total 4g), lidocaine (loading dose of 1mg/kg and infusion of 2–4mg/min), and overdriving temporary pacing with a rate of 100beats/min for recurrent TdP (B), along with intravenous fluid, dopamine (20μg/kg/min) and noradrenaline (4μg/min) for persistent hypotension, but unfortunately died the next day. Amitraz and its metabolites were measured with gas liquid chromatography: the results were 2,4-dimethyl formanilide (BTS-27919) of 8.96mg/ml and N′-(2,4-dimethylphenyl)-N-methyl-formamidine (BTS-27271) of 6.08mg/ml in the serum and amitraz of 0.78mg/ml, BTS-27919 of 19.60mg/ml and BTS-27271 of 0.49mg/ml in the urine. Other toxicological investigations were normal, including acetylycholinesterase, paraquat, solvents, and basic drug screen.

The effectiveness of a procedure is dependent on the willingness of people to actually do the procedure

Scott Davison, John Hunsucker — 2010-01-04

Often resuscitation studies use simple survival ratios to show the effectiveness of a procedure—that is the number of people who survived a procedure divided by the number of people who received the procedure. However, it is very important to understand that a simple survival ratio can drastically underestimate the real effectiveness of a procedure. This can be seen, for example, in Bystander CPR (BCPR) live discharge rates. In one study, when 722 out-of-hospital cardiac arrests (OOHCA) occurred, 153 patients received BCPR. The study stated that 22 of those 153 patients were eventually discharged from the hospital for a live discharge rate of 18.3%. For the 569 patients who did not receive BCPR, 48 survived for a live discharge rate of 8%.

Emergencies in the kindergarten: Are kindergarten teachers adequately trained to cardiopulmonary resuscitation?

Dong Hoon Lee, Yoon Hee Choi, Young Jin Cheon — 2010-01-14

Among the Organization for Economic Cooperation and Development (OECD) countries, Korea has a relatively high incidence of childhood injury and deaths caused by safety hazards. Compared with adults, infants and children are more threatened by injury and death from safety hazards, so teachers should have the knowledge and skills to cope with these emergencies. The nuclearization of families and the expansion of women's roles have reduced the amount of time parents provide for raising their infants and children. Many infants and children spend more time at nurseries and kindergartens than they do at home, so these places become their second home. Although many studies have been conducted on first aid for teachers at nurseries and kindergartens, teachers’ knowledge of cardiopulmonary resuscitation (CPR) for infants and children has not been investigated. We evaluated the CPR knowledge of teachers at nurseries and kindergartens to determine where further education might improve the quality of childcare. The subjects were 323 nursery and kindergarten teachers in Seoul, Korea. Four hundred copies of questionnaires were distributed and 350 ones were returned. Seventeen questionnaires with unanswered questions or incorrectly answered questions were excluded leaving 323 copies that were analyzed. One hundred and ninety (58.8%) teachers had undertaken first aid classes. Two hundred and eighty-nine teachers did not know how to perform CPR for infants and children and only two could perform CPR correctly ().