Cardiopulmonary resuscitation and post-resuscitation care

Survival and subsequent good neurological outcome following cardiac arrest depends on prompt diagnosis, good quality cardiopulmonary resuscitation (CPR) with minimal interruptions and rapid defibrillation, if appropriate. In the post-resuscitation phase, diagnosis and treatment of the underlying cause for the arrest with avoidance of hypotension, hyperthermia, hyperoxia, hyper/hypoglycaemia and management of seizure activity confers the best chances of a successful outcome. Early prognostication of survivors is difficult and should be done by experts using a variety of proven modalities.     

Cardiopulmonary resuscitation and post-resuscitation care

Survival and subsequent good neurological outcome following cardiac arrest depends on prompt diagnosis, good quality cardiopulmonary resuscitation (CPR) with minimal interruptions and rapid defibrillation, if appropriate. In the post resuscitation phase, diagnosis and treatment of the underlying cause for the arrest with avoidance of hypotension, hyperthermia, hyperoxia, hyper/hypoglycaemia and management of seizure activity confers the best chances of a successful outcome. Early prognostication of survivors is difficult and should be done by experts using a variety of proven modalities.     

Severe pallid breath-holding spells treated with low-dose theophylline

BackgroundThe medical treatment for severe pallid breath-holding spells accompanied with severe bradycardia or transient cardiac arrest is controversial. Although various medications have been reported to be effective, patients treated with pacemaker insertion are not always evaluated for pharmacological therapy beforehand.Case reportA 9-month-old boy developed pallid breath-holding spells. At 15 months of age, a Holter electrocardiogram revealed 12 s of asystole during a breath-holding spell. Treatment with low-dose theophylline sustained-release dry syrup (5.3 mg/kg/day) led to complete control of the spells. The peak concentration of theophylline was 4.4 μg/mL which was below the therapeutic range for bronchial asthma. When he turned 3 years and 5 months of age, theophylline treatment was discontinued without recurrence of pallid breath-holding spells.DiscussionTheophylline is now infrequently used to treat pediatric bronchial asthma due to its limited effect coupled with its side effects, which include headache, digestive symptoms, and theophylline-associated convulsions. The effectiveness of theophylline as a treatment for pallid breath-holding spells has been reported in several reports. In our case, the theophylline dosage was approximately half the amount described in previous reports.ConclusionsIn this case, low-dose theophylline was adequate in controlling the pallid breath-holding spells. Because theophylline-associated seizures are a major concern, we suggest an evaluation of low-dose theophylline for treating patients with severe pallid breath-holding spells without febrile convulsions or epilepsy before proceeding with permanent pacemaker insertion. Further development of preventive strategies for theophylline-associated seizures and characterization of patients who respond well to theophylline treatment is required.     

Asystole and bradycardia in adult patients after a single dose of suxamethonium

Two cases of cardiac asystole and one case of severe bradycardia were seen following a single injection of suxamethonium in a series of 46 adult patients in whom anaesthesia was induced with fentanyl and etomidate. It is suggested that the vagomimetic effects of fentanyl and, possibly also of etomidate, may contribute to the enhancement of the bradycardic effects of suxamethonium.     

Sympathoinhibition and hypotension in carotid sinus hypersensitivity

Carotid sinus reflex hypersensitivity is a known cause of syncope in humans. The condition is characterized by cardioinhibition and vasodepression, each to varying degrees. The extent and importance of sympathoinhibition has not been determined in patients with carotid sinus hypersensitivity. This study reports on the extent of sympathoinhibition measured directly during carotid massage with and without atrioventricular sequential pacing, in a patient with symptomatic carotid sinus reflex hypersensitivity. Carotid massage elicited asystole, hypotension and complete inhibition of muscle sympathetic nerve activity. Carotid massage during atrioventricular pacing produced similar sympathoinhibition, but with minimal hypotension. Therefore, sympathoinhibition did not contribute importantly to the hypotension during carotid massage in the supine position in this patient. Further investigations are required to elucidate the relation of sympathoinhibition to hypotension in patients with carotid sinus hypersensitivity in the upright position.     

Breathing during cardiac arrest following exercise: A new function of the respiratory system?

We have found in four sheep that, following a muscular exercise, minute ventilation is maintained for 34-131 s during a cardiac arrest (CA), at a magnitude (from 28.2 and 54.7 l min(-1)) similar to the level of ventilation (and thus proportional to the metabolic rate) preceding the period of asystole. Breathing was maintained despite the lack of pulmonary blood flow and the cessation of the muscle contractions, leading to a dramatic reduction in alveolar FCO(2) (1.9 ± 1%). Secondly, swings in arterial blood pressure (ABP) were observed (pulse pressure of 31 ± 3 Torr) in phase with breathing movements in place of the cardiac activity. This "protective" response, deprived from any role in blood gas homeostasis, as circulation is virtually abolished, is not predictable from the traditional respiratory control feedback systems thought to be involved in exercise. We are presenting the view that this response, dissociated from the pulmonary gas exchanges, is the expression of a rudimentary defense mechanism aimed at limiting the consequences of an acute failure of the cardiac pump by the thoraco-abdominal pump.     

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

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 ≤5 min, 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 ≤30 min 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.     

Bradycardia progressing to cardiac arrest during adenosine thallium myocardial perfusion imaging in occult sino-atrial disease

Adenosine is used increasingly as an alternative to dynamic exercise during myocardial perfusion imaging because it is a powerful coronary vasodilator with a short half-life. Minor side-effects are common but life-threatening events are rare. We report two cases of provocation by adenosine infusion of profound sinus bradycardia progressing to atrial and ventricular asystole. Despite discontinuation of the infusion, asystole persisted for up to 1 min in one case and was accompanied by a grand mal seizure. Normal sinus rhythm returned spontaneously in both cases without long-term sequelae. Sino-atrial disease was later suggested in both cases by 24-h electrocardiographic monitoring. We conclude that patients to whom adenosine is given may have occult sino-atrial disease and may be susceptible to life-threatening arrhythmias. Significant sinus bradycardia during the infusion may provide a warning of its presence.     

The Impact of Variation in Donation After Cardiac Death Policies Among Donor Hospitals: A Regional Analysis

The Joint Commission requires all hospitals have a policy regarding donation after cardiac death. To this date however, a quantitative analysis of adult hospital donation after cardiac death (DCD) policies and its impact on transplantation outcomes has not been reported. Specific characteristics for DCD polices were identified from 90 of the 164 (54.9%) hospitals within the New England Organ Bank's donor service area. Forty‐five policies (50.0%) allow family members to be present during withdrawal of life‐sustaining therapy (WLST) whereas eight (8.9%) prohibit this. Seventeen policies (18.9%) require WLST to occur in the operating room (OR); 20 (22.2%) specify a location outside of the OR. Fifty‐six (62.2%) policies fail to state the method of determining death; however, some require arterial line (15 policies, 16.6%) and/or EKG (10 policies, 11.1%). These variables were not associated with organ recovery, utilization or donor ischemia time. Our regional analysis highlights the high degree of variability of hospital DCD policies, which may contribute to misunderstanding and confusion among providers and patients that may influence acceptance of this mode of donation.