Search

In an effort to determine the impact of halothane anesthesia on certain human cell-mediated immune functions, normal, purified human monocytes and lymphocytes were exposed to halothane in vitro at varying concentrations for up to 8 hours. Subsequently, these human effector cells were analyzed for their ability to function in several cell-mediated immunologic assays. Natural killer cell activity against K-562 was unaffected by halothane in most of the donors tested. Similarly, the ability of purified monocytes to inhibit MBL-2 tumor cell growth was unchanged. Halothane appeared to decrease the proliferative response of lymphocytes to phytohemagglutinin (PHA) in approximately 50% of the normal donors tested. In contrast, the ability of monocytes to lyse antibody-coated red cell targets (ADCC) was unaffected by even maximal exposure to halothane. Of interest was the finding that human monocytes exposed to as low as 2% halothane anesthesia for 4 hours displayed a dramatic down-regulation of hydrogen peroxide (H2O2) release. Since it is known that hydrogen peroxide and other incompletely reduced forms of oxygen secreted by monocytes can play a major role in the antimicrobial, antitumor, and inflammatory functions of these cells, this finding may help explain the enhanced susceptibility of post-operative patients to infections.

A novel system for exposing purified human mononuclear leukocyte subsets or any cultured cell to inhalational anesthetic agents has been devised. Monocytes and lymphocytes are purified by counter-current centrifugal elutriation and put into culture vessels with and without appropriate functional activators. The culture vessels are placed into one of four anesthetic agent exposure chambers, each containing a different concentration of the anesthetic agent to be tested. The system that delivers the anesthetic agent to the culture vessels is essentially the same as the one used in the operating room; the actual levels of anesthetic agent delivered are monitored. In this report, we present evidence that halothane can be successfully tested using the above-cited experimental design; this agent substantially inhibits the secretion of interferon by human mononuclear cells. The ability of monocytes to secrete α interferon in response to polyinosinic: polycytidylic acid (poly I: C) was significantly depressed following 4 h in vitro exposure to increasing concentrations of halothane; the secretion of γ interferon by lymphocytes in response to phytohemagglutinin (PHA) was also depressed, although to a lesser degree. The system presented should allow for the in vitro exploration of the effects of inhalational agents on purified human leukocyte subset functions as well as for the analysis of the effect of these agents on monocyte/lymphocyte interactions.

Nalbuphine (EN2234A) is an agonist-antagonist analgesic. It is structurally related to the narcotic analgesic oxymorphone and to the narcotic antagonist naloxone. A double blind study was carried out in 400 children in ASA classification I, ranging from 10 months to 14 years of age, to compare nalbuphine, pentazocine and placebo for paediatric premedication. Our results showed that nalbuphine is comparable to pentazocine as a premedicating agent and superior to placebo, in the doses used, and that premedication is an important adjunct to anaesthesia in children. Following premedication with nalbuphine or pentazocine, there were fewer apprehensive children at the time of induction of anaesthesia and in the recovery room when compared to those receiving placebo injections.

This double-blind study assessed the effect of low dose droperidol (0.005 mg x kg-1) on the incidence of postoperative vomiting in 200 children in ASA classification I and II, ranging from one to 15 years of age. The results showed that the dose of droperidol used in this study was very effective in reducing vomiting in children 11 to 15 years of age. The duration of stay in the post-anaesthetic care unit was not prolonged and no extrapyramidal symptoms related to the drug were observed. In our opinion the administration of droperidol 0.005 mg x kg-1 before the end of the operation will reduce the possibility of vomiting within 24 hours of operation in children in 11-15 year age group who are expected to have a high incidence of postoperative vomiting.

Ketamine, pancuronium, and alphaprodine were used as the primary anesthetic agents in 71 infants requiring cardiovascular operations during a recent 1-year period. This group of patients was compared with a similar group anesthetized 3 years before with d-tubocurarine, halothane, and/or N20-O2. Stability of the circulatory system was well maintained with ketamine-pancuronium-narcotic (KPN) during the induction period. However, once surgical dissection of the heart and great vessels began, hypotension/bradycardia, ventricular fibrillation, and 48-hour mortality were similar for the two groups. Therefore, using these criteria for analysis, the KPN technic, in spite of claims for its minimal adverse effect on the cardiovascular system, did not prove superior to the halothane-N2O-O2-curare technic.