Left ventricular assist devices for the treatment of congestive heart failure

Optional statement The mainstay of heart failure therapy is aggressive medical management with consideration of resynchronization therapy and automatic implantable cardioverter-defibrillator. This is best done with the support of a multidisciplinary team. Transplantation, when possible, remains the therapy of choice for patients who are refractory to medical therapy. Other options short of left ventricular assist device (LVAD) that should be considered include revascularization, mitral valve repair, and left ventricular remodeling procedures. LVAD therapy as a bridge to transplantation should be considered in patients with heart failure who are clinically deteriorating while on the transplant waiting list. This should be initiated prior to the onset of irreversible end-organ damage. In nontransplant candidates, an LVAD can be considered as an alternative to transplantation (destination therapy). However, cost and the availability of expertise continue to limit this therapy to quaternary care and research institutions.     

Patterns of respiratory response of rabbits to histamine

We analysed the respiratory response of anaesthetised rabbits to aerosols or injections of histamine. Shortening of expiratory duration (t _E) could preceed shortening of inspiratory duration (t _I) by a few breaths (continuous acceleration) ort _I could remain constant until an augmented breath preceded a large reduction int _I (discontinuous acceleration). The responses were not appreciably modified by a block of pulmonary stretch receptors and are therefore attributable to increased activity of lung irritant and, to a lesser extent, C-fibre receptors. The results are discussed in relation to the mechanisms controllingt _I andt _E. We conclude that such mechanisms are relatively independent under certain circumstances and that irritant receptors may have an indirect role in shorteningt _I.     

Developing a client-focused allocation statistic of inpatient nursing resource use: an alternative to the patient day

A sample survey (N = 2660) was conducted at eight acute care hospitals in New Jersey during an 11-month period between 1979 and 1981 in order to develop a client-focused, case-mix sensitive measure of resource use for the allocation of inpatient general nursing costs. Using general linear modelling techniques, the direct and indirect effects of age, length of stay, multiple diagnoses, multiple procedures, the ratio of special care unit days to length of stay and the effects of the presence of surgery, admission status, discharge status and membership in Major Diagnostic Categories on indexed total units of nursing service were explored. The results of the analysis suggested that length of stay is the most significant predictor of indexed nursing units of service regardless of age and the complexity of the medical problem when case-mix is controlled through the assignment of cases to 13 nursing services isoresource clusters. The methodology yields an empirically derived patient-specific, case-mix adjusted length of stay statistic which can be used to apportion nursing costs by the case. The approach permits the estimation of nursing units of service which reflect the relative amount of nursing inputs and corresponding costs of direct patient care consumed by any given inpatient in any given hospital.     

Coronary and peripheral arterial responses to ergometrine in patients susceptible to coronary and oesophageal spasm.

Vascular responses to ergometrine were compared in groups of patients subject to coronary artery spasm, or oesophageal spasm, or neither. We measured the degree of diffuse narrowing at different coronary artery sites (not in spasm), and the rise in blood pressure. The data provide no evidence for a generalised sensitivity to alpha-adrenergic stimulation underlying either of these two clinical entities. The left main stem was narrowed significantly less than the three main branches of the coronary artery tree. The degree of diffuse coronary artery narrowing was not influenced by the presence or absence of minor (less than or equal to 50%) fixed stenotic lesions, nor by the initial calibre of the arteries. Ergometrine did not alter arterial lactate concentration or lactate extraction in the absence of coronary spasm.