Influence of Minor Dental Surgery with and without Intravenous Sedation on Levels of Hormones Responsible for Volume Homeostasis in Elderly Hypertensive Patients.

Changes in the hormones responsible for volume homeostasis were observed before, during, and after minor dental surgery in 25 elderly hypertensive patients. These patients were divided into two groups. Group L patients were operated on using local anesthesia alone. Group LS patients were operated on using local anesthesia and intravenous sedation together. We found that plasma renin activity and aldosterone and vasopressin levels did not change intraoperatively in either group. We also found that intraoperative plasma human atrial natriuretic peptide (HANP) levels and systolic blood pressure were significantly elevated in group L and significantly decreased in group LS. Before local anesthesia was administered, HANP levels in both groups were already higher than the normal range in healthy adults. Therefore, these results suggest that increased HANP levels represent a compensatory response to offset further elevation of blood pressure. However, these increases did not seem to be sufficient to actually cause a decrease in blood pressure.

Responses to intravenous sedation by elderly patients at the Hokkaido University Dental Hospital.

Geriatric patients who undergo intravenous sedation require careful intraoperative management, because respiratory and circulatory depression usually accompanies the administration of recommended adult sedative doses. This study examined results when a single benzodiazepine, diazepam or flunitrazepam, was carefully titrated to a clinical endpoint of conscious sedation. A total of 335 cases was divided into seven age groups. Mean sedative doses gradually decreased with age. The 60- to 69-yr group required about 75% of the adult recommended dose, the 70- to 79-yr group required 40% to 60%, and the 80- to 89-yr group required 30% to 45%. Pulse oximetry values also declined with age; respiratory depression was observed mainly in elderly patients. Declines in blood pressure after benzodiazepine administration were not correlated with age. The rise in blood pressure normally observed intraoperatively was suppressed both in young as well as old patients. We conclude that intravenous conscious sedation in elderly patients reduces stress-induced cardiovascular stimulation and that respiratory depression may occur at even low sedative doses.