Some Circulatory Aspects of the Oxygen Transport in Patients with Emphysema

Abstract

67 patients were studied by pulmonary function and heart catheterization at rest, during exercise and after 20min 100% oxygen breathing. 14 patients were diagnosed as having COLD without chronic respiratory insufficiency (CRI). 45 patients were considered to be suffering from pulmonary emphysema (COLD + CRI). In this group, 23 patients had normal hemoglobin concentrations (C_Hb), 14 patients demonstrated decreased values and 8 had secondary polycythemia. All groups of patients had a normal cardiac output (CO), oxygen consumption (VO₂) and pulmonary wedge pressure (P_w) at rest and after oxygen breathing. In the group with COLD and CRI high values for pulmonary vascular resistance (R_p) were found, most pronounced in those with polycythemia. All groups of patients except the polycythemia group demonstrated a significant decrease of R_p during oxygen breathing, but only a slight decrease of pulmonary arterial pressure (P_pa)· It can be concluded that a normal quantity of oxygen transport to peripheral tissues in patients with arterial hypoxemia can be achieved by maintaining normal values for arterial mixed venous oxygen content without a shift of the oxygen dissociation curve.

A survey of the recreational rock-angling fishery at Port Elizabeth, on the south-east coast of South Africa

“…Such multi-user and multi-species fisheries are difficult to manage (Sainsbury 1982, Smale andBuxton 1985), particularly when benefits derived from the resource differ among the users. Economic, recreational, nutritional and social benefits are all associated with the linefish resource, and the management strategies needed to satisfy these benefits are not necessarily compatible (Gulland 1978, Van der Elst 1985, Butterworth et al 1989. Clearly, the prime objective should be to manage the resource in a manner in which the harvest will provide the greatest overall benefit to the community.…”

The Port Alfred fishery: a description and preliminary evaluation of a commercial linefishery on the South African east coast

“…The A-licences are held by full-time commercial fishermen and the Blicences by part-time fishermen. Both categories place certain restrictions on the fishermen and these are summarized by Van der Elst (1985).…”

“…Catches of sea catfish are erratic and largely dependent on the depth at which fishing takes place, not being caught deeper than 55 m. Catches do not appear to be affected by changing environmental conditions and sea catfish are caught all year round, usually in association with kobo Some 3 per cent of the kob catch is smaller than the legal minimum size of 400 mm TL (see Van der Elst [1985] or Penney et at. [1989] for a summary of legal minimum sizes).…”

“…6j) at 225 mm FL. Thel engths at first recruitment of (til the species are above T: the legal minimum of250 mm TL (Van der Elst 1985, -8 Penney et 01. 1989.…”