Acute posthypoxic myoclonus after cardiopulmonary resuscitation

ABSTRACT: BACKGROUND: Acute posthypoxic myoclonus (PHM) can occur in patients admitted after cardiopulmonary resuscitation (CPR) and is considered to have a poor prognosis. The origin can be cortical and/or subcortical and this might be an important determinant for treatment options and prognosis. The aim of the study was to investigate whether acute PHM originates from cortical or subcortical structures, using somatosensory evoked potential (SEP) and electroencephalogram (EEG). METHODS: Patients with acute PHM (focal myoclonus or status myoclonus) within 72 hours after CPR were retrospectively selected from a multicenter cohort study. All patients were treated with hypothermia. Criteria for cortical origin of the myoclonus were: giant SEP potentials; or epileptic activity, status epilepticus, or generalized periodic discharges on the EEG (no back-averaging was used). Good outcome was defined as good recovery or moderate disability after 6 months. RESULTS: Acute PHM was reported in 79/391 patients (20%). SEPs were available in 51/79 patients and in 27 of them (53%) N20 potentials were present. Giant potentials were seen in 3 patients. EEGs were available in 36/79 patients with 23/36 (64%) patients fulfilling criteria for a cortical origin. Nine patients (12%) had a good outcome. A broad variety of drugs was used for treatment. CONCLUSIONS: The results of this study show that acute PHM originates from subcortical, as well as cortical structures. Outcome of patients admitted after CPR who develop acute PHM in this cohort was better than previously reported in literature. The broad variety of drugs used for treatment shows the existing uncertainty about optimal treatment.     

Appraisal of pediatric cardiopulmonary resuscitation.

Sixty-six patients more than 30 days and less thant 16 years of age suffering an unexpected cardiac arrest in an 18-month period were included in a study of resuscitative measures in children. Six children survived to be discharged from hospital. Respiratory disease accounted for most (29%) of the cardiac arrests, but it also had the most favourable prognosis, 21% of the 19 patients surviving. None of the patients survived whose cardiac arrest was secondary to sepsis or trauma, even when the resuscitative efforts were initially successful. Only 1 of the 41 patients who had a cardiac arrest outside of hospital survived, and only 1 of the 34 patients who presented with asystole survived, and then with considerable damage to the central nervous system. The interval between cardiac arrest and application of basic life support was substantially shorter among the survivors. Also, most of the survivors did not present with asystole. The results of this study suggest that survival among resuscitated children is no better than that among adults but can be improved with early recognition and monitoring of children at risk. earlier application of basic and advanced life support, improved education of medical and lay personnel, and further research into pediatric resuscitative techniques.     

A community training scheme in cardiopulmonary resuscitation.

Community instruction in basic life support and resuscitation techniques has been offered in Brighton Health District since 1978. Classes are held frequently for the general public and businesses, schools, and other organisations. First aid care for unconscious patients, the treatment of respiratory obstruction or failure, and the recognition and management of cardiac arrest is taught in a single two hour session. Over 20 000 people have been taught, up to 40 at a time in multiple groups of six to eight, by lay instructors usually supervised by ambulancemen trained to "paramedic" standards. Fifty four incidents have been reported to us in which techniques learnt in the classes have been implemented. Five patients recovered after first aid support but subsequently did not seek medical treatment. Of the 34 patients reviewed in hospital, at least 20 survived to be discharged. We believe that intervention may have been life saving in 16 instances. The benefit of cardiopulmonary resuscitation for victims who may have been asystolic is, however, difficult to quantify because the outcome without intervention cannot be predicted accurately. Community training in basic life support should be considered in association with ambulances equipped for resuscitation and hospital intensive care and cardiac care units as an integrated service for the victims of sudden circulatory or respiratory emergencies. The results achieved so far in Brighton and in other more advanced schemes, particularly in the United States of America, may encourage other health authorities to adopt similar programmes.     

Age-related changes in chest geometry during cardiopulmonary resuscitation

We studied alterations of chest geometry during conventional cardiopulmonary resuscitation in anesthetized immature swine. Pulsatile force was applied to the sternum in increments to determine the effects of increasing compression on chest geometry and intrathoracic vascular pressures. In 2-wk- and 1-mo-old piglets, permanent changes in chest shape developed due to incomplete recoil of the chest along the anteroposterior axis, and large intrathoracic vascular pressures were generated. In 3-mo-old animals, permanent chest deformity did not develop, and large intrathoracic vascular pressures were not produced. We propose a theoretical model of the chest as an elliptic cylinder. Pulsatile displacement along the minor axis of an ellipse produces a greater decrease in cross-sectional area than displacement of a circular cross section. As thoracic cross section became less circular due to deformity, greater changes in thoracic volume, and hence pressure, were produced. With extreme deformity at high force, pulsatile displacement became limited, diminishing pressure generation. We conclude that changes in chest geometry are important in producing intrathoracic intravascular pressure during conventional cardiopulmonary resuscitation in piglets.     

Successful management of postinfarction ventricular septal rupture

Ventricular septal rupture is a rare but devastating complication of acute myocardial infarction. Especially in patients with cardiogenic shock, right ventricular dysfunction or an inferior infarct mortality is very high. We present a case in which an 83-year-old patient survived rupture of the ventricular septum complicating an inferior myocardial infarction. Unlike most patients his haemodynamic status did not deteriorate and delayed elective surgical repair was carried out successfully.