Acute myocardial infarction during pregnancy successfully treated with primary percutaneous coronary intervention

We report a case of a 40 year old pregnant woman who presented with an acute myocardial infarction (AMI) complicated by ventricular fibrillation. She underwent successful primary percutaneous coronary intervention (PCI). With a tendency towards increased maternal age in developed countries, AMI during pregnancy may become a more frequent occurrence.

A four-step approach for establishment of a national medical response to mega-terrorism

A simplified, four-step approach was used to establish a medical management and response plan to mega-terrorism in Israel. The basic steps of this approach are: (1) analysis of a scenario based on past incidents; (2) description of relevant capabilities of the medical system; (3) analysis of gaps between the scenario and the expected response; and (4) development of an operational framework. Analyses of both the scenario and medical abilities led to the recommendation of an evidence-based contingency plan for mega-terrorism. An important lesson learned from the analyses is that a shortage in medical first responders would require the administration of advanced life support (ALS) by paramedics at the scene, along with simultaneous, rapid evacuation of urgent casualties to nearby hospitals by medics practicing basic life support (BLS). Ambulances and helicopters should triage casualties from inner to outer circle hospitals secondarily, preferentially Level-1 trauma centers. In conclusion, this four-step approach based on scenario analysis, mapping of medical capabilities, detection of bottlenecks, and establishment of a unique operational framework, can help other medical systems develop a response plan to mega-terrorist attacks.

Impact of advanced cardiac life support-skilled paramedics on survival from out-of-hospital cardiac arrest in a statewide emergency medical service

BACKGROUND

Prehospital research has found little evidence in support of advanced cardiac life support (ACLS) for out-of-hospital cardiac arrest. However, these studies generally examine city-based emergency medical services (EMS) systems. The training and experience of ACLS-skilled paramedics differs internationally, and this may also contribute to negative findings. Additionally, the frequency of negative outcome in out-of-hospital cardiac arrest suggests that it is difficult to establish sufficient numbers to detect an effect.

PURPOSE

To examine the effect of ACLS on cardiac arrest in Queensland, Australia. Queensland has a population of 3.8 million and an area of over 1.7 million km2, and is served by a statewide EMS system, which deploys resources using a two-tier model. Advanced treatments such as intubation and cardioactive drug administration are provided by extensively trained intensive care paramedics.

METHODS

An observational, retrospective design was used to examine all cases of cardiac arrest attended by the Queensland Ambulance Service from January 2000 to December 2002. Logistic regression was used to examine the effect of the presence of an intensive care paramedic on survival to hospital discharge, adjusting for age, sex, initial rhythm, the presence of a witness and bystander cardiopulmonary resuscitation.

RESULTS

The presence of an intensive care paramedic had a significant effect on survival (OR = 1.43, 95% CI = 1.02 to 1.99).

CONCLUSIONS

Highly trained ACLS-skilled paramedics provide added survival benefit in EMS systems not optimised for early defibrillation. The reasons for this benefit are multifactorial, but may be the result of greater skill level and more informed use of the full range of prehospital interventions.

Successful extracorporeal life support in cardiac arrest with recurrent ventricular fibrillation unresponsive to standard cardiopulmonary resuscitation

Extracorporeal life support has been used as an extension of conventional cardiopulmonary resuscitation (CPR). However, the appropriate indications for extracorporeal CPR (ECPR) including the duration of CPR are unknown. We present a case of a male, 37-year-old out-of-hospital cardiac arrest patient who received prolonged CPR followed by ECPR. Despite advanced cardiac life support, he did not regain a sustained spontaneous circulation and had recurrent ventricular fibrillation (VF) during the prolonged CPR. VF was unresponsive to CPR, defibrillation, adrenaline (epinephrine), and antiarrhythmics. The CPR time before ECPR was approximately 2h. During extracorporeal life support, the VF did not recur and percutaneous coronary angioplasty was achieved. Ultimately, the patient was discharged without neurological complications. Although cardiac arrest occurred out-of-hospital and CPR was performed for a long time, a patient might be a candidate for ECPR if perfusing rhythms are restored transiently but not successfully maintained due to recurrent VF. ECPR may be used for VF unresponsive to standard CPR techniques.

Nuevas recomendaciones para el registro uniforme de datos en la reanimación cardiopulmonar avanzada. Estilo Utstein pediátrico

Pediatric patients requiring cardiopulmonary resuscitation show high morbidity and mortality. There are few studies on this topic and existing studies use distinct terminology and methodology in data collection, hampering comparisons, efficiency assessment, and meta-analyses, etc. Consequently, in clinical studies of cardiorespiratory arrest (CRA) and cardiopulmonary resuscitation (CPR) in the pediatric age group, data collection should be performed in a uniform manner. To define the criteria that allow uniform data collection, in 2004 a working group of the International Liaison Committee on Resuscitation published simplified recommendations for registering essential information, which could be applicable to adults and children both in clinical practice and research, as well as inside and outside the hospital setting. Following the Utstein style, the Spanish Group of Pediatric and Neonatal CPR has designed an algorithm and a data collection form for recording essential CPA data. The need for these documents to be designed with maximum accuracy is stressed, both because of their medico-legal and professional implications and because of the influence of some variables on post-CPA recovery. Likewise, while protecting patient confidentiality, provincial, regional and national CPA registries should be developed, which would improve the quality of care, research, and resource provision according to needs.

Emergency medical service systems in Japan: past, present, and future

Emergency medical services are provided by the fire defence headquarters of the local government in Japan. There is a one-tiered EMS system. Ambulances are staffed by three crew members trained in rescue, stabilisation, transport, and advanced care of traumatic and medical emergencies. There are three levels of care provided by ambulance personnel including a basic-level ambulance crew (First Aid Class One, FAC-1), a second level (Standard First Aid Class, SFAC), and the highest level (Emergency Life Saving Technician, ELST). ELSTs are trained in all aspects of BLS and some ALS procedures relevant to pre-hospital emergency care. Further development of an effective medical control system is imperative as the activities of ambulance crews become more sophisticated. A marked recent increase in the volume of emergency calls is another issue of concern. Currently, private services for transportation of non-acute or minor injury/illness have been introduced in some areas, and dispatch protocols to triage 119 calls are being developed.

Conventional neurocritical care and cerebral oxygenation after traumatic brain injury

Object

Control of intracranial pressure (ICP) and cerebral perfusion pressure (CPP) is the foundation of traumatic brain injury (TBI) management. In this study, the authors examined whether conventional ICP- and CPP-guided neurocritical care ensures adequate brain tissue O2 in the first 6 hours after resuscitation.

Methods

Resuscitated patients with severe TBI (Glasgow Coma Scale score ≤ 8 and Injury Severity Scale score ≥ 16) who were admitted to a Level I trauma center and who underwent brain tissue O2 monitoring within 6 hours of injury were evaluated as part of a prospective observational database. Therapy was directed to maintain an ICP of 25 mm Hg or less and a CPP of 60 mm Hg or higher.

Data from a group of 25 patients that included 19 men and six women (mean age 39 ± 20 years) were examined. After resuscitation, ICP was 25 mm Hg or less in 84% and CPP was 60 mm Hg or greater in 88% of the patients. Brain O2 probes were allowed to stabilize; the initial brain tissue O2 level was 25 mm Hg or less in 68% of the patients, 20 mm Hg or less in 56%, and 10 mm Hg or less in 36%. Nearly one third (29%) of patients with ICP readings of 25 mm Hg or less and 27% with CPP levels of 60 mm Hg or greater had severe cerebral hypoxia (brain tissue O2 ≤10 mm Hg). Nineteen patients had both optimal ICP (≤25 mm Hg) and CPP (> 60 mm Hg); brain tissue O2 was 20 mm Hg or less in 47% and 10 mm Hg or less in 21% of these patients. The mortality rate was higher in patients with reduced brain tissue O2.

Conclusions

Brain resuscitation based on current neurocritical care standards (that is, control of ICP and CPP) does not prevent cerebral hypoxia in some patients. This finding may help explain why secondary neuronal injury occurs in some patients with adequate CPP and suggests that the definition of adequate brain resuscitation after TBI may need to be reconsidered.

The culture of a trauma team in relation to human factors

AIM

The aim of this ethnographic study was to explore the culture of a trauma team in relation to human factors.

BACKGROUND

Traumatic injury is the leading cause of death in the first four decades of life in the western world. Evidence suggests that the initial assessment and resuscitation of trauma victims is most successfully carried out by an organized trauma team. Most trauma teams use Advanced Trauma Life Support principles which focus on rapid assessment and management of the patient's injuries. Similarly, most trauma education focuses on Advanced Trauma Life Support principles, concentrating firmly on the patient's physical status. Nevertheless, contemporary literature about emergency teams suggests that human factors, such as communication and interprofessional relationships, can affect the team's performance regardless of how clinically skilled the team members are.

METHOD

Focused ethnography was used to explore the culture of a trauma team in one teaching hospital. Six periods of observation were undertaken followed by 11 semi-structured interviews with purposively chosen key personnel. Data from transcripts of the observation field notes and interviews were analysed using open coding, followed by formation of categories resulting in the emergence of six central categories.

RESULTS

Findings suggest that leadership, role competence, conflict, communication, the environment and the status of the patient all influence the culture of the trauma team. Interpretation of these categories suggests that trauma team education should include human factor considerations such as leadership skills, team management, interprofessional teamwork, conflict resolution and communication strategies.

RELEVANCE FOR CLINICAL PRACTICE

The findings suggest that support systems for role development of junior team leaders should be formalized. The proven airline industry techniques of Crew Resource Management, focusing on teamwork and effective communication, could be implemented into continuing professional development for trauma teams to engender collaboration and interprofessional practice.

Could a computer-based system including a prevalence function support emergency medical systems and improve the allocation of life support level?

OBJECTIVES

To evaluate whether a computer-based decision support system could be useful for the emergency medical system when identifying patients with acute myocardial infarction (AMI) or life-threatening conditions and thereby improve the allocation of life support level.

METHODS

Patients in the Municipality of Göteborg who dialled the dispatch centre due to chest pain during a period of 3 months. To analyse the relationship between patient characteristics (according to a case record form used during an interview) and the response variables (AMI or life-threatening condition), multivariate logistic regression was used. For each patient, the probability of AMI/life-threatening condition was estimated by the model. We used these probabilities retrospectively to allocate advanced life support or basic life support. This model allocation was then compared with the true allocation made by the dispatchers.

RESULTS

The sensitivity, that is, the percentage of AMI patients allocated to advanced life support, was 85.7% in relation to the true allocation made by the dispatchers. The corresponding sensitivity regarding allocation made by the model was 92.4% (P=0.17). The specificity was also slightly higher for the model allocation than the dispatcher allocation. Among the 15 patients with AMI who were allocated to basic life support by the dispatchers, nine died (eight during and one after hospitalization). Among the eight patients with AMI allocated to basic life support by the model, only one patient died (in hospital) (P=0.02).

CONCLUSION

A computer-based decision support system including a prevalence function could be a valuable tool for allocating the level of life support. The case record form, however, used for the interview can be refined and a model based on a larger sample and confirmed in a prospective study is recommended.

Prospective performance evaluation of emergency medical services for cardiac arrest in Lombardia: is something moving forward?

BACKGROUND

Limited data are available in our region on out-of-hospital treatment of cardiac arrest. The aim of this study is to evaluate whether the changes implemented in the emergency system (i.e. an increased number of basic life support and advance life support crews that were dispatched) produced the expected outcome improvements.

METHODS

(a)

EXPERIMENTAL DESIGN

data were prospectively collected on patients with sudden out-of-hospital cardiac arrest in three emergency dispatch centers for 3 months during two study periods, year 2000 and year 2003, differentiated only by the increase of qualified crews. Outcomes and survival were evaluated at 24 h and 1 month after the event. (b)

SETTING

out-of-hospital treatment. (c)

PATIENTS

352 (174 in the second study period) patients suffering cardiac arrest. (d)

INTERVENTIONS

the study was observational.

RESULTS

We could document, between the two study periods, stable 24 h (12.6 vs 9.1%) and 1 month survival (3.4 vs 5.8%, NS). Nevertheless, arrival time on site was significantly higher in the second period (from 8.3+/-3.3 to 10.1+/-5.4 min, P<0.05).

CONCLUSIONS

The strengthening of only one link of the chain-of-survival did not improve 1 month survival.

Enoximone in cardiac arrest caused by propranolol: two case reports

We report two clinical cases of cardiac arrest, the former due to an adverse effect of intravenous (i.v.) propranolol in a patient with systemic sclerosis, the latter from a propranolol suicidal overdose. In both cases, conventional advanced life support (ALS) was ineffective but both patients eventually responded to the administration of enoximone, a phosphodiesterase III (PDE III) inhibitor. After the arrest, both patients regained consciousness and were discharged home. The chronotropic and inotropic effects of PDE III inhibitors are due to inhibition of intracellular PDEIII and are therefore unaffected by beta-blockers. These cases suggest that PDEIII inhibitors may be useful in restoring spontaneous circulation in cardiac arrest associated with beta-blocker administration when standard ALS is ineffective.

Graduating internal medicine residents' self-assessment and performance of advanced cardiac life support skills

Internal medicine residents in the US must be competent to perform procedures including Advanced Cardiac Life Support (ACLS) to become board-eligible. Our aim was to determine if residents near graduation could assess their skills in ACLS procedures accurately. Participants were 40 residents in a university-based training program. Self-assessments of confidence in managing six ACLS scenarios were measured on a 0 (very low) to 100 (very high) scale. These were compared to reliable observational ratings of residents' performance on a high-fidelity simulator using published treatment protocols. Residents expressed strong self-confidence about managing the scenarios. Residents' simulator performance varied widely (range from 45% to 94%). Self-confidence assessments correlated poorly with performance (median r = 0.075). Self-assessment of performance by graduating internal medicine residents was not accurate in this study. The use of self-assessment to document resident competence in procedures such as ACLS is not a proxy for objective evaluation.

Aminophylline in bradyasystolic cardiac arrest: a randomised placebo-controlled trial

BACKGROUND

Endogenous adenosine might cause or perpetuate bradyasystole. Our aim was to determine whether aminophylline, an adenosine antagonist, increases the rate of return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest.

METHODS

In a double-blind trial, we randomly assigned 971 patients older than 16 years with asystole or pulseless electrical activity at fewer than 60 beats per minute, and who were unresponsive to initial treatment with epinephrine and atropine, to receive intravenous aminophylline (250 mg, and an additional 250 mg if necessary) (n=486) or placebo (n=485). The patients were enrolled between January, 2001 and September, 2003, from 1886 people who had had cardiac arrests. Standard resuscitation measures were used for at least 10 mins after the study drug was administered. Analysis was by intention-to-treat. This trial is registered with the ClinicalTrials.gov registry with the number NCT00312273.

FINDINGS

Baseline characteristics and survival predictors were similar in both groups. The median time from the arrival of the advanced life-support paramedic team to study drug administration was 13 min. The proportion of patients who had an ROSC was 24.5% in the aminophylline group and 23.7% in the placebo group (difference 0.8%; 95% CI -4.6% to 6.2%; p=0.778). The proportion of patients with non-sinus tachyarrhythmias after study drug administration was 34.6% in the aminophylline group and 26.2% in the placebo group (p=0.004). Survival to hospital admission and survival to hospital discharge were not significantly different between the groups. A multivariate logistic regression analysis showed no evidence of a significant subgroup or interactive effect from aminophylline.

INTERPRETATION

Although aminophylline increases non-sinus tachyarrhythmias, we noted no evidence that it significantly increases the proportion of patients who achieve ROSC after bradyasystolic cardiac arrest.

Extracorporeal life support after staged palliation of a functional single ventricle: Subsequent morbidity and survival

OBJECTIVE

We sought to review the outcome of infants with a functional single ventricle receiving postoperative extracorporeal life support.

METHODS

We reviewed all patients with a functional single ventricle receiving postoperative extracorporeal life support between January 1997 and May 2003.

RESULTS

We supported 25 infants (age range, 2-139 days; median age, 15 days; weight range, 1.9-5.9 kg; median weight, 3.4 kg) with extracorporeal life support. Operative procedures were Norwood stage 1 procedure in 18 patients, modified Blalock-Taussig shunt in 4 patients, bidirectional superior cavopulmonary shunt in 2 patients, and pulmonary vein repair in 1 patient. Indications for extracorporeal life support included cardiac arrest (14/25) and low cardiac output state (11/25). Extracorporeal membrane oxygenation was initiated in 19 patients, with conversion to a ventricular assist device in 7 patients. Ventricular assist device alone was initiated in 6 patients. Survival to decannulation was 76%, with 5 late deaths from multiorgan failure and 56% intensive care unit survival. Survival to hospital discharge was 44%. On univariate analysis, the presence of arrhythmia before extracorporeal life support (P = .005), renal failure (P = .0007), Candida species-induced sepsis (P = .026), and multiorgan failure (P = .0009) were significant risk factors in the nonsurvivors. Median hospital stay was 43.5 days (range, 6-181 days) for the whole group and 93 days (range, 36-181 days) for survivors. Eight patients completed next stage palliation.

CONCLUSIONS

Twenty percent of patients were supported with a ventricular assist device alone, with 50% conversion to a ventricular assist device from extracorporeal membrane oxygenation. Survival to decannulation was encouraging. Multiorgan failure and risk of invasive infection in the post-extracorporeal membrane oxygenation period mitigate against survival to hospital discharge. Use of extracorporeal life support before cardiac arrest might reduce attrition between decannulation and hospital discharge.

Cold simple intravenous infusions preceding special endovascular cooling for faster induction of mild hypothermia after cardiac arrest--a feasibility study

OBJECTIVE

Mild therapeutic hypothermia has shown to improve neurological outcome after cardiac arrest. Our study investigated the efficacy and safety of cold simple intravenous infusions for induction of hypothermia after cardiac arrest preceding further cooling and maintenance of hypothermia by specialised endovascular cooling.

METHODS

All patients admitted after cardiac arrest of presumed cardiac aetiology were screened. Patients enrolled received 2000 ml of ice-cold (4 degrees C) fluids via peripheral venous catheters. As soon as possible endovascular cooling was applied even if the cold infusions were not completed. The target temperature was defined as 33 +/- 1 degrees C. All temperatures recorded were measured via bladder-temperature probes. The primary endpoint was the time from return of spontaneous circulation to reaching the target temperature. Secondary endpoints were changes in haemodynamic variables, oxygenation, haemoglobin, clotting variables and neurological outcome.

RESULTS

Out of 167 screened patients 26 (15%) were included. With a total amount of 24 +/- 7 ml/kg cold fluid at 4 degrees C the temperature could be lowered from 35.6 +/- 1.3 degrees C on admission to 33.8 +/- 1.1 degrees C. The target temperature was reached 185 +/- 119 min after return of spontaneous circulation, 135 +/- 112 min after start of infusion, and 83 +/- 85 min after start of endovascular cooling. Except for two patients showing radiographic signs of mild pulmonary edema no complications attributable to the infusions could be observed. Thirteen patients (50%) survived with favourable neurological outcome.

CONCLUSION

Our results indicate that induction of mild hypothermia with infusion of cold fluids preceding endovascular cooling is safe and effective.

[Prehospital life support in trauma patients: basic or advanced trauma life support]

The controversy between Advanced Trauma Life Support (ATLS) and Basic Life Support (BLS) in the prehospital care of trauma patients has not been resolved yet. The purpose of this study was to examine the literature with respect to the type of prehospital care applied to the trauma patients. A total of 76 papers on ATLS and/or BLS for trauma were reviewed regarding the variables such as intravenous catheter application, prehospital fluid resuscitation, transport time, intubation and mortality. As a conclusion, the data in the literature do not support the routine use of on-field ATLS in trauma patients. Prospective randomized trials comparing ATLS and BLS in prehospital management of trauma patients are needed to clarify this issue.

Analysis of the outcome for patients experiencing myocardial infarction and cardiopulmonary resuscitation refractory to conventional therapies necessitating extracorporeal life support rescue*

OBJECTIVE

To analyze the results of acute myocardial infarction (AMI) complicated with refractory shock necessitating extracorporeal life support (ECLS) rescue and to search for associated risk factors.

DESIGN

Retrospective review of our 9-yr experience with patients initially presenting with AMI with shock necessitating ECLS rescue; analysis of patient outcomes.

SETTING

A university-affiliated tertiary referral medical center.

PATIENTS

Between 1994 and 2003 inclusively, 36 consecutive patients (age [mean +/- sd], 57 +/- 10 yrs) with AMI complicated by refractory shock and undergoing cardiopulmonary resuscitation (CPR) necessitating emergent ECLS rescue were enrolled in this study.

INTERVENTION

All patients underwent CPR before ECLS, although 30 patients (83.3%) received ECLS during CPR because spontaneous circulation failed to return. All patients underwent intraaortic counterpulsation either before or following rescue. Seven patients underwent angioplasty only, and one underwent heart transplantation without any intervention. Twenty-eight patients underwent coronary artery bypass grafting (CABG), in which the beating-heart technique was used for 20 patients.

MEASUREMENTS AND MAIN RESULTS

The pre-ECLS blood lactate level was high (13.4 +/- 8.5 mmol/L), as was the inotropic score (121.4 +/- 117.3 microg/kg/min). Twenty-five patients (69.4%) were successfully weaned off ECLS, and 12 (48%) survived to discharge (one had a neurologic deficit). The overall mortality rate was 66.7%. A lower inotropic score, reduced blood lactate level, shorter CPR duration, surgical revascularization, and a reduced total maximal Sepsis-related Organ Failure Assessment (SOFA) score were noted among survivors. Liver failure, central nervous system failure, and renal failure mainly occurred in nonsurvivors after ECLS. The technique used for surgical revascularization (beating heart or arrested heart) did not influence the outcome. ECLS is associated with a lower mortality rate than that expected (>90%) from the resultant total maximal SOFA score (16.6 +/- 3.0).

CONCLUSIONS

: AMI complicated with refractory shock remains associated with a high mortality rate, even following ECLS rescue, although ECLS might afford a better chance of survival. The SOFA score can be applied to ECLS condition as a reference point for predicting outcome.

Sodium bicarbonate improves outcome in prolonged prehospital cardiac arrest

OBJECTIVE

This study evaluates the effect of early administration of an empirical (1 mEq/kg) sodium bicarbonate dose on survival from prehospital cardiac arrest within brief (<5 minutes), moderate (5-15 minutes), and prolonged (>15 minutes) down time.

METHODS

Prospective randomized, double-blinded clinical intervention trial that enrolled 874 prehospital cardiopulmonary arrest patients managed by prehospital, suburban, and rural regional emergency medical services. Over a 4-year period, the randomized experimental group received an empirical dose of bicarbonate (1 mEq/kg) after standard advanced cardiac life support interventions. Outcome was measured as survival to emergency department, as this was a prehospital study.

RESULTS

The overall survival rate was 13.9% (110/792) for prehospital arrest patients. There was no difference in the amount of sodium bicarbonate administered to nonsurvivors (0.859 +/- 0.284 mEq/kg) and survivors (0.8683 +/- 0.284 mEq/kg) (P = .199). Overall, there was no difference in survival in those who received bicarbonate (7.4% [58/420]), compared with those who received placebo (6.7% [52/372]) (P = .88; risk ratio, 1.0236; 0.142-0.1387). There was, however, a trend toward improved outcome with bicarbonate in prolonged (>15 minute) arrest with a 2-fold increase in survival (32.8% vs 15.4%; P = .007).

CONCLUSION

The empirical early administration of sodium bicarbonate (1 mEq/kg) has no effect on the overall outcome in prehospital cardiac arrest. However, a trend toward improvement in prolonged (>15 minutes) arrest outcome was noted.