Does the efficacy of supplemental oxygen for the prevention of postoperative nausea and vomiting depend on the measured outcome, observational period or site of surgery?

High intra-operative oxygen concentration reportedly reduces postoperative nausea and vomiting (PONV), but recent data are conflicting. Therefore, we tested whether the effectiveness of supplemental oxygen depends on the endpoint (nausea vs. vomiting), observation interval (early vs. late) or surgical field (abdominal vs. non-abdominal). We randomly assigned 560 adult patients undergoing various elective procedures with a PONV risk of at least 40% to intra-operative 80% (supplemental) or 30% oxygen (control). Potential confounding factors were similar between groups. Incidences of nausea were similar in the groups during early (12% (supplemental) vs. 10% (control), p = 0.43) and late intervals, 26%vs. 20%, p = 0.09, as were the incidences of vomiting (early: 2%vs. 3%, p = 0.40; late: 8%vs. 9%, p = 0.75). Supplemental oxygen was no more effective at reducing PONV in abdominal (40%vs. 31%, p = 0.37) than in non-abdominal surgery (25%vs. 21%, p = 0.368). Thus, supplemental oxygen was unable to reduce PONV independent of the endpoint, observational period or site of surgery.

[Influence of neonatally administered gonadotropin on the sexual function of adult rats]. / Der Einfluss neonataler Gonadotropingaben auf die Sexualfunktionen erwachsener Ratten

Male and female rats were daily injected with 10 IU HCG plus 10 IU FSH from the 1st to 14th day of life in order to investigate the influence of neonatal gonadotrophin administration on the sex-specific differentiation of the brain. When adult, the males showed hypogonadism associated with approximately normal sexual activity. In the females, precocious puberty, indicated by premature vaginal opening and spontaneous estrus, occurred. Furthermore, bisexuality with a tendency towards more male behavioural patterns was observed, but no impairment of ovarian cyclicity. Thus, hypergonadotrophic hypergonadism during the hypothalamic differentiation phase gave rise to bisexual behaviour in adult female rats associated with normal ovarian cycles. The question of a direct or indirect influence of gonadotrophins on the sex-specific brain differentiation is discussed.