New guidelines for cardiopulmonary resuscitation and emergency cardiac care: changes in the management of cardiac arrest

Electrocardiograms: a guide to rhythm recognition for emergency nurses

Electrocardiogram (ECG) is one of the most commonly performed investigations in emergency departments (EDs), and is an extremely useful adjunct that guides diagnosis, prognosis and treatment. In most cases nurses are the first healthcare professional to assess patients and record an ECG, yet anecdotal evidence suggests that few emergency nurses review, interpret and act on ECG findings. Research suggests this may be due to lack of confidence in, or knowledge about, interpretation of results, often because of inadequate training. This article aims to help emergency nurses understand and interpret the cardiac rhythms commonly encountered on ECGs in EDs, to enable them to support earlier diagnosis and treatment. It describes a simple, five-step method for evaluating the main components of cardiac rhythm.

Implementation of a high-performance cardiopulmonary resuscitation protocol at a collegiate emergency medical services program

Out-of-hospital cardiac arrest (OHCA) is a significant public health issue. Although OHCA occurs relatively infrequently in the collegiate environment, educational institutions with on-campus emergency medical services (EMS) agencies are uniquely positioned to provide high-quality resuscitation care in an expedient fashion. Georgetown University's on-campus EMS program recently updated its medical protocols to reflect the latest literature in resuscitation science. In a high-performance CPR (HPCPR) resuscitation, minimally interrupted chest compressions are emphasized, along with a coordinated team-based approach.

Vasopressin in the pediatric cardiac intensive care unit: Myth or reality

Pediatric cardiac surgery is undergoing a metamorphosis, with more and more critical patients being operated in our country today. Although the principles of physiology have not changed, it is imperative that care providers continue to stay abreast with developments and newer drugs that may help modify the outcome. The team dynamics have also become more complex, which necessitates the need for all care providers (surgeons, cardiologists, anesthesiologists, and intensivists) to better understand the interactions and benefits of newer drugs. Vasopressin has been used in our adult patients for more than a decade and recently has found its rightful place in the pediatric armoury. The objective of this article is to review the physiology of vasopressin and the rationale of its use in critically ill children with shock, in context of the available published data.

Vasopressin in pediatric shock and cardiac arrest

OBJECTIVE

To review the physiology and the published literature on the role of vasopressin in shock in children.

DATA SOURCE

We searched MEDLINE (1966-2007), EMBASE (1980-2007), and the Cochrane Library, using the terms vasopressin, terlipressin, and shock and synonyms or related terms for relevant studies in pediatrics. We searched the online ISRCTN-Current Controlled Trials registry for ongoing trials. We reviewed the reference lists of all identified studies and reviews as well as personal files to identify other published studies.

RESULTS

Beneficial effects have been reported in vasodilatory shock and asystolic cardiac arrest in adults. Solid evidence for vasopressin use in children is scant. Observational studies have reported an improvement in blood pressure and rapid weaning off catecholamines during administration of low-dose vasopressin. Dosing in children is extrapolated from adult studies.

CONCLUSIONS

Vasopressin offers promise in shock and cardiac arrest in children. However, in view of the limited experience with vasopressin, it should be used with caution. Results of a double-blind, randomized controlled trial in children with vasodilatory shock will be available soon.

Ultra long cardiopulmonary resuscitation with intact cerebral performance for an asystolic patient with acute myocarditis

Cardiopulmonary resuscitation (CPR) for 10-30 min without return of spontaneous circulation is considered to have a grave prognosis. We report a 27-year-old woman who experienced in-hospital, witnessed cardiac arrest and underwent prolonged CPR with manual chest compressions for 280 min. Adequate chest compression was monitored with femoral arterial pressure monitoring. During this time, she was alert and responsive. She was then supported with extracorporeal membrane oxygenation (ECMO) for 9 days without her heart beating. After combined heart and kidney transplantation, she recovered well with intact cerebral performance. This successful case report supports the endeavours for relentless CPR efforts.

Can Nifekalant Hydrochloride be Used as a First-Line Drug for Cardiopulmonary Arrest (CPA)?

BACKGROUND

Early defibrillation of ventricular tachycardia and fibrillation (VT/VF) is an urgent and most important method of resuscitation for survival in cardiopulmonary arrest (CPA). We have previously reported that nifekalant (NIF), a specific I(Kr) blocker developed in Japan, is effective for lidocaine (LID) resistant VT/VF in out-of-hospital CPA (OHCPA). However, little is known about the differences in the effect of NIF on OHCPA with acidosis and in-hospital CPA (IHCPA) without acidosis.

METHODS AND RESULTS

The present study enrolled 91 cases of DC shock resistant VT/VF among 892 cases of CPA that occurred between June 2000 and May 2003. NIF was used (0.15-0.3 mg/kg) after LID according to the cardiopulmonary resuscitation (CPR) algorithm of Tokai University. The defibrillation rate was higher in the NIF group for both OHCPA and IHCPA than for LID alone, and the VT/VF rate reduction effect could be maintained even with acidosis. However, sinus bradycardia in OHCPA, and torsades de pointes in IHCPA were occasionally observed. These differences in adverse effects might be related to the amount of epinephrine, serum potassium levels, serum pH, and interaction with LID.

CONCLUSIONS

NIF had a favorable defibrillating effect in both CPA groups, and it shows promise of becoming a first-line drug for CPR.

Combined Effects of Nifekalant and Lidocaine on the Spiral-Type Re-Entry in a Perfused 2-Dimensional Layer of Rabbit Ventricular Myocardium

BACKGROUND

Spiral re-entry plays the principal role in the genesis of ventricular tachycardia and ventricular fibrillation (VT/VF). The specific I(Kr) blocker, nifekakant (NIF) has, often in combination with lidocaine (LID), recently been used in Japan to prevent recurrent VT/VF, but the combined effects of these drugs on spiral re-entry had never been investigated.

METHODS AND RESULTS

A ventricular epicardial sheet was obtained from 13 Langendorff-perfused rabbit hearts by means of a cryoprocedure, and epicardial excitations were analyzed with a high-resolution optical mapping system. Nifekakant (0.5 micromol/L) caused significant prolongation of action potential duration (APD) and LID (3 micromol/L) attenuated the APD prolongation without affecting the conduction velocity. VT were induced in 6 hearts by cross-field stimulation, and single- or double-loop spirals circulating around variable functional block lines were visualized during the VT. Nifekakant reduced VT cycle length and caused early termination in association with destabilization of the spiral dynamics (prolongation of functional block line, frequent local conduction block, and extensive meandering). These modifications of spiral-type re-entrant VT by NIF were prevented by addition of LID.

CONCLUSIONS

The effects of NIF on the spiral excitations are reversed by LID. This interaction should be taken into account when these drugs are used in combination to treat VT/VF.

Percutaneous transcricoid jet ventilation compared with surgical cricothyroidotomy in a sheep airway salvage model

BACKGROUND

We developed a large animal model of the "cannot intubate/cannot ventilate" (CNI/V) scenario to compare percutaneous transcricoid manual jet ventilation (MJV) with surgical cricothyroidotomy (SC).

METHODS

Twelve sheep weighing 40-80 kg were assigned to MJV or SC groups. After sedation, intubation, and line placement, CNI/V was simulated by removing the tracheal tube and inducing paralysis with vecuronium. When SaO2 reached 80% (t=0), MJV catheter insertion or SC was initiated. Upon successful airway placement, ventilation began using 100% oxygen at 20 breaths/min. MJV was administered at 50 psi. HR, BP, SaO2, pH, PCO2, and PO2 were recorded at t=0, 30, 60, 90, 120, 150, 180, 300, 600, and 1200 s. Data were reported as mean+/-S.E.M. over the whole observation period. Baseline values were compared using Student's t-tests. Repeated-values ANOVA was used for post-procedure group comparisons. Statistical tests were two-tailed and alpha was set at 0.05.

RESULTS

Body weights were not significantly (P=0.08) different between MJV (65+/-6 kg) and SC (52+/-3 kg) groups. Baseline respiratory and hemodynamic variables were also not significantly different. Median procedure time for MJV (20 s) and SC (24 s) was not significantly (P=0.69) different. Post-procedure values were not significantly different for SaO2 (P=0.65), pH (P=0.70), PCO2 (P=0.47), PO2 (P=0.84), MAP (P=0.09), or HR (P=0.16) over the entire 20 min resuscitation period.

CONCLUSION

Using a realistic model of CNI/V we found no difference in respiratory or hemodynamic variables between MJV and SC. Adequate ventilation and perfusion was maintained solely by MJV for up to 20 min.

Perceived Self-Efficacy in Performing and Willingness to Learn Cardiopulmonary Resuscitation in an Elderly Population in a Suburban Community

• Background Older persons are the group most likely to respond to cardiac arrests in private residences.

• Objective To characterize the knowledge about, attitudes toward, and perceived self-efficacy of older persons in learning and providing cardiopulmonary resuscitation.

• Methods A total of 2743 surveys were mailed to adults 55 years and older who resided in a single Michigan suburb. Data were collected on demographics, medical history, training in and willingness to provide cardiopulmonary resuscitation, and concerns about providing this intervention.

• Results The 631 persons (24.6%) who responded were elderly (mean age, 73.5 years) and had a mean of 1.7 occupants per household. More than one third lived alone. Of all respondents, 275 (43.6%) had received training in cardiopulmonary resuscitation, 370 (58.6%) indicated a willingness to learn cardiopulmonary resuscitation, and 412 (65.3%) thought that they had the ability to perform this intervention. Respondents 80 years or younger were significantly more likely than respondents more than 80 years old to be willing to learn cardiopulmonary resuscitation (65.7% vs 19.0%, P < .001) and perceived themselves as able to perform it (73.0% vs 34.0%, P < .001). The absence of mouth-to-mouth ventilation as part of training had minimal impact on the willingness of either age group to receive training (61.2% vs 58.6%, P = .19). Perceived ability to learn and perform cardiopulmonary resuscitation did not vary with the medical history of the respondent or the respondent’s spouse.

• Conclusion Adults 56 to 80 years old perceive themselves as able to perform cardiopulmonary resuscitation and are interested in receiving training.

Vasopressin in cardiovascular patients: therapeutic implications

Vasopressin is a vital homeostatic protein which regulates fluid balance via its antidiuretic effects and vascular tone via its vasoconstrictive effects. Endogenous vasopressin deficiency has been implicated in several disease states resulting in vasodilatory shock. In particular, vasopressin levels are low in patients following cardiac surgery and in those with ventricular dysrhythmias. Several recent studies have demonstrated the effectiveness of exogenous vasopressin in providing haemodynamic support in patients with postcardiopulmonary bypass vasodilatory shock and refractory ventricular fibrillation. This manuscript reviews the pathophysiological and clinical basis for vasopressin replacement in patients with cardiovascular collapse.

Teaching basic life support skills using self-directed learning, a self-instructional video, access to practice manikins and learning in pairs

Applying adult learning principles in healthcare education is increasingly recognised as useful and effective. We designed and evaluated an educational package for medical student basic life support (BLS) skills that placed the responsibility of skill acquisition with the learner. The package provided hardcopy and web based information, an in-house produced audio-video tape demonstrating BLS, and open access to manikins in a Skills Centre where the students learnt in pairs. Students determined when they were ready to be assessed. This assessment was performed by two independent observers using the Resuscitation Council (UK) BLS assessment sheet. Two groups, comprising in total 51 fourth year medical students were assessed, 47 were found to be competent in performing BLS on their first assessment. Of the remaining four, three were assessed as competent after further self-directed learning and retesting. Only one student required personal tutoring prior to success. Self-directed learning is a successful method of mastering BLS. Where failure occurred, it was due to inadequate student learning in the Skills Centre. The importance of practice needs emphasis in future use of the programme, as does the virtual guarantee of success, if all steps are followed. A similar programme could be devised for other technical skills.

Effects of alcohol on the heart

Some evidence suggests that light to moderate alcohol consumption protects against cardiovascular diseases. However, this cardioprotective effect of alcohol consumption in adults is absent at the population level. Approximately 20 to 30% of patients admitted to a hospital are alcohol abusers. In medical practice, it is essential that patients' levels of consumption are known because of the many adverse effects that might result in the course of routine care. Ethanol damage to the heart is evident if alcohol consumption exceeds 90 to 100 g/d. Heavy ethanol consumption leads to increased risk for sudden cardiac death and cardiac arrhythmias. In patients with coronary heart disease, alcohol use was associated with increased mortality. An early response to drinking was an increased ventricular wall thickness to diameter ratio, possibly proceeding with continuous drinking to alcoholic cardiomyopathy, which had a worse outcome compared with idiopathic dilative cardiomyopathy if drinking was not stopped or at least reduced (< 60 g/d). In the ICU, patients with chronic alcoholism have more cardiac complications postoperatively. These complications probably are caused by biventricular dysfunction, particularly with the occurrence of severe infections or septic shock, events that are three to four times more frequent among chronic alcoholics than occasional drinkers or nondrinkers. To prevent further complications from drinking and for long-term management of drinking, patients with alcohol abuse and heart failure should be treated in brief intervention and follow-up programs. Prognosis is good even in patients with New York Heart Association class IV heart failure caused by cardiomyopathy if complete abstinence is accomplished. Noncompliance to smoking and alcohol restrictions, which are amenable to change, dramatically increases the risk for hospital readmissions among patients with heart failure.