Out-of-hospital cardiac arrest without return of spontaneous circulation in the field: Who are the survivors?

Background: Return of spontaneous circulation (ROSC) in the field is a vital determinant contributing to survival from out-of-hospital cardiac arrest (OHCA). However, nearly one third of survivors at the Dallas-Fort Worth (DFW) Resuscitation Outcomes Consortium (ROC) site did not obtain ROSC in the field.

Methods: A retrospective, observational analysis was performed on all adult patients with non-traumatic OHCA treated on scene and transported to hospital, who did not gain ROSC in the field at DFW ROC site between 2006 through 2011.

Year in review 2012: Critical Care--Out-of-hospital cardiac arrest and trauma.

In 2012 Critical Care published many articles pertaining to the resuscitation of out-of-hospital cardiac arrest and trauma. In this review, we summarize several of these articles, including those regarding advances in resuscitation techniques and methods. We examine articles pertaining to prehospital endotracheal intubation, the use of specialized devices for cardiopulmonary resuscitation and policies regarding transport destinations for both cardiac arrest and trauma patients.

The aetiology and course of isolated severe aortic regurgitation: a clinical, pathological, and echocardiographic study.

Seventy two consecutive patients with severe isolated aortic regurgitation were evaluated by preoperative echocardiographic and angiographic assessment of the aortic root. Biopsy specimens of the aortic wall were taken at operation. Two major groups of patients were found: those with cusp derangement but normal aortic roots and those with normal cusps but dilated aortic roots.

Inappropriate left ventricular hypertrophy in minor aortic valve disease: a source of error in clinical assessment.

A group of patients with minor aortic valve disease and inappropriately severe left ventricular hypertrophy is described. Clinical, electrocardiographic and echocardiographic assessment of the degree of left ventricular hypertrophy suggested that they had haemodynamically severe aortic stenosis but this was not borne out at cardiac catheterisation. Although a chance association between non-obstructive hypertrophic cardiomyopathy and mild aortic stenosis may have been responsible, an abnormally severe hypertrophic response to minor aortic outflow obstruction is proposed as another possible explanation.

Changes in echocardiographic left ventricular minor axis dimensions during exercise in patients with aortic stenosis.

Twelve patients with aortic stenosis (gradient 62 (25) mm Hg), and six normal subjects were examined using M mode echocardiography before and during submaximal bicycle exercise. Normal subjects showed a progressive fall in the end systolic minor axis dimension of the left ventricle and a rise in end diastolic dimension, giving an increase in stroke dimension and shortening fraction of 45% and 37% respectively at peak exercise. Patients with aortic stenosis showed no consistent alteration in either end systolic or end diastolic dimension, and consequently stroke dimension was unchanged during exercise.

The loud first heart sound in left atrial myxoma.

The interrelation between the loudness of the first heart sound, the time interval from the Q wave to the onset of the first heart sound (QM1), and the mitral valve closure rate was studied in nine patients presenting with left atrial myxomata. In seven patients the first heart sound was loud preoperatively and was associated with delayed mitral valve closure. After removal of the myxoma the onset of mitral valve closure returned towards normal, the mitral valve closure rate was reduced, and the first heart sound became softer.

Comparison of cinefluoroscopy and M mode echocardiography for detecting aortic valve calcification. Correlation with severity of stenosis of non-rheumatic aetiology.

The density of aortic valve calcification was estimated using cinefluoroscopy and M mode echocardiography in 86 patients with pure aortic stenosis. The results were compared with the degree of outflow obstruction measured haemodynamically. Cinefluoroscopic estimates of aortic valve calcification correlated well with the measured aortic valve gradient whereas echocardiographic results were less accurate.

Significance of complete right bundle-branch block when an isolated finding. An echocardiographic study.

Twenty-seven patients with complete right bundle-branch block as the only abnormal finding were studied using high speed M-mode echocardiography to determine the effect of the electrical delay on the mechanical events of right ventricular systole. Pulmonary valve opening (PVOm) was delayed in all cases. In some the delay was mainly between mitral valve closure (MVC) and tricuspid valve closure (TVC), and this was designated proximal block.

Unsuspected coronary artery disease as cause of chronic atrioventricular block in middle age.

Attention has recently been drawn to the relatively poor prognosis of middle aged patients paced for chronic atrioventricular block when age-linked expectation of life is taken into account, and it has been suggested that this may be the result of underlying coronary artery disease, despite the absence of symptoms to suggest this. It was the purpose of this study to determine the incidence of unsuspected coronary artery disease in middle aged patients presenting with chronic atrioventricular block. Studies were made on a consecutive series of 30 patients aged 45 to 65 (mean age 56 years) with chronic atrioventricular disease who had been referred for pacing.

Non-invasive diagnosis of subpulmonary outflow tract obstruction.

We have studied the echocardiographic and phonocardiographic findings in 18 patients with obstruction to ventricular outflow at subpulmonary valve level. The aetiology was congenital in 13 patients, a result of hypertrophic cardiomyopathy in three, and infiltration of the right ventricular outflow tract by glycogen or lymphoma in the remaining two. Abnormal systolic motion of the pulmonary valve, fluttering, and early or midsystolic closure were seen in 16 of 17 patients in whom the cusps were visualised.

Septicemia in patients with an endocardial pacemaker.

The records of 1,235 consecutive patients treated with long-term pacing by the endocardial route between 1964 and 1977 were analyzed to determine the incidence, mechanism, course and treatment of septicemia. Septicemia developed in 12 patients (1 percent), and Staphylococcus aureus was isolated from the blood culture in 10. All patients were treated with the usual prolonged course of bactericidal drugs.

Complete right bundle-branch block: echophonocardiographic study of first heart sound and right ventricular contraction times.

High speed enchocardiograms of the mitral, tricuspid, and pulmonary valves were recorded with a simultaneous electrocardiogram and phonocardiogram in 20 patients with complete right bundle-branch block and in 67 normal subjects. Late opening of the pulmonary valve indicating late right ventricular ejection was found in all patients. In 8 patients with wide splitting of the first heart sound the late ejection was related mainly to delay in tricuspid valve closure, suggesting a late onset of the right ventricular pressure pulse.

Prognosis of patients paced for chronic atrioventricular block.

Between the years 1960 and 1974, 839 patients were paced for chronic complete atrioventricular block. Analysis of survival compared with the general population showed that 170 deaths were expected according to standard mortality tables and 288 actually occurred, giving a ratio of actual to expected deaths of 1.7:1.