The effect of total parenteral nutrition and morphine on ventilation.

Total parenteral nutrition (TPN), specifically amino acid infusions, has been shown to increase the ventilatory response to inhaled CO2. The hypothesis tested was that morphine sulfate (known to depress ventilatory CO2 responsiveness) would diminish the augmented ventilatory CO2 response in patients receiving TPN. The influence of morphine on hyperoxic hypercapnic ventilatory response (assessed by the Read rebreathing technique) was therefore examined in four otherwise healthy subjects who were receiving TPN at home for long-standing nutritional support secondary to malabsorption syndrome (short-bowel syndrome), and in a control group of four healthy subjects who were not receiving TPN. The slope and intercept of the CO2 response was estimated by linear regression on the relationship between ventilation (VE) and end-tidal PCO2 (PETCO2). Administration of morphine in the non-TPN group elicited the expected decrease in the VE-PETCO2 slope. In contrast, morphine administration was associated with an increase in the VE-PETCO2 slope in the TPN group. While this investigation does not provide a direct indication of the mechanisms underlying the augmenting action of morphine on the ventilatory response to CO2 in subjects receiving TPN, it does suggest that patients on TPN who demonstrate no impairment of ventilatory control may be given normal doses of morphine sulphate (ie, as for pain control or preoperative medication) with no increased concern for an adverse ventilatory outcome.

Health promotion for older Americans.

The purpose of this article is to provide a general overview of health promotion issues relevant to older Americans. As part of a national health promotion initiative for older people, sponsored by the US Public Health Service and the Administration on Aging, research was undertaken to study the health status, knowledge, attitudes and practices of this population. Six health behaviors identified in the study, entitled Aging and Health Promotion: Market Research for Public Education, which can positively influence the well-being of older people, will be briefly discussed: exercise, nutrition, injury prevention, safe use of medicines, use of preventive services and smoking cessation. Recommendations will be made for the development of health promotion messages focusing on these health habits.

Renal damage in systemic lupus erythematosus with normal renal function.

Renal biopsies were performed on 12 patients with definite systemic lupus erythematosus (SLE) with normal renal function. Three had had previous nephropathy which responded to treatment, with return of urinalysis and function to normal. Specimens were studied using light microscopy (LM), immunofluorescence (IF), and electron microscopy (EM). Mild to moderate abnormalities were found in all patients. Changes by LM (primarily hypercellularity) were found in 11 specimens (no glomeruli were obtained in one) and classified as inactive. IF studies were positive in eight of the 12 biopsies with either focal or diffuse distribution of IgG, IgM, and/or C3. EM changes were observed in all cases and were of mild to moderate severity. They included focal to multifocal glomerular hypercellularity, basement membrane thickening, foot process fusion, and mesangial and intramembranous electron dense deposits. No subepithelial or subendothelial deposits were found. Microtubular structures were present in three specimens. These data suggest that careful study of renal biopsy specimens may reveal evidence of kidney involvement in all patients with SLE.