Inhibitory effects of desflurane and sevoflurane on oxytocin-induced contractions of isolated pregnant human myometrium.

BACKGROUND: In this study, we investigated the inhibitory effects of desflurane and sevoflurane on oxytocin-induced contractions of isolated human myometrium. METHODS: Following delivery of the infant and placenta, a small segment of myometrium was excised from the upper incisional surface of the lower uterine segment and 20 strips, randomly assigned into two groups (n = 10), were obtained from 20 non-laboring term parturients. The study protocol consisted of a 60-min period of spontaneous contractions, control recording with oxytocin 2 x 10(9) m (10-min period), washout interval of 10 min, volatile administration (three times per 15-min period) of 0.5, 1 and 2 minimum alveolar concentration (MAC), response to oxytocin (10-min period), a further washout interval (10-min period) and subsequent control recording with oxytocin without anesthetics. RESULTS: After oxytocin administration, the frequency and amplitude of contractions increased (P < 0.05) and the duration decreased (P < 0.05). The frequency and amplitude of contractions induced with oxytocin decreased significantly at 0.5, 1 and 2 MAC of desflurane and sevoflurane (P < 0.05). The amplitude of contractions was significantly different at 1 MAC between the two groups (P < 0.05). The duration of contractions at 2 MAC decreased in both groups (P < 0.05). CONCLUSIONS: Desflurane and sevoflurane at 0.5, 1 and 2 MAC inhibit the frequency and amplitude of myometrial contractions induced with oxytocin in a dose-dependent manner. However, desflurane inhibits the amplitude less than sevoflurane at 1 MAC. We suggest that 0.5 MAC of both agents and 1 MAC of desflurane may be safely used in the presence of oxytocin following delivery of the infant and placenta during Cesarean section without fear of uterine atony and hemorrhage.

Inhibitory effects of desflurane and sevoflurane on contractions of isolated gravid rat myometrium under oxytocin stimulation.

BACKGROUND: We studied the inhibitory effects of desflurane and sevoflurane on oxytocin-induced contractions of isolated gravid rat myometrium. METHODS: Twenty strips were obtained from rats and these were randomly assigned into two groups. The effects of desflurane and sevoflurane were evaluated by treating strips with oxytocin alone 2x10-9 M or with oxytocin after desflurane and sevoflurane at 0.5, 1, and 2 MAC. RESULTS: Oxytocin significantly increased the amplitude and duration of contractions (P< 0.05), but it did not increase the frequency. The duration (84%, 79%), amplitude (90%, 84%) and frequency (88%, 75%) were inhibited at 2 MAC of desflurane and sevoflurane, respectively. CONCLUSION: These results suggest that the in vitro application of desflurane and sevoflurane similarly inhibit oxytocin-induced myometrial contractions of gravid rat in a dose-dependent manner.

The direct depressant effects of desflurane and sevoflurane on spontaneous contractions of isolated gravid rat myometrium.

Our purpose was to investigate the direct depressant effects of desflurane and sevoflurane at 0.5, 1 and 2 minimum alveolar concentrations (MAC) on spontaneous contractions of isolated gravid rat myometrium. Ten gravid, albino Wistar rats, weighing 240-310 g and at 19-20 days' gestation were used. Sixty myometrial strips were obtained from 10 rats, and randomly assigned into six groups of 10. After obtaining spontaneous myometrial contractions in de Jalon solution for 45 min, 0.5, 1 or 2 MAC of desflurane or sevoflurane were continuously bubbled in the bath for 15 min and myometrial contractions evaluated during the last 10 min. Desflurane 0.5 MAC did not affect duration or amplitude of spontaneous contractions, but frequency was significantly decreased (P < 0.05). Duration, amplitude and frequency were all significantly decreased by desflurane 1 and 2 MAC (P < 0.05). Sevoflurane did not affect duration, amplitude or frequency at 0.5 MAC, but amplitude and frequency were significantly decreased at 1 MAC and all were significantly decreased at 2 MAC (P < 0.05). The frequency of contractions was decreased 21.2% with 1 MAC desflurane versus 17.1% with 1 MAC sevoflurane. The amplitude and frequency of contractions were decreased 48.2% and 48.7% with 2 MAC desflurane versus 58.9% and 49.3% with 2 MAC sevoflurane, respectively. We suggest that due to tocolytic activity, desflurane and sevoflurane can be useful in non-obstetric surgery during pregnancy.

Laser therapy in chronic cervicitis.

Chronic cervicitis is one of the common disorders encountered in daily practice. To overcome this problem first step should be antibiotic therapy in acute phase. If this fails, the infection becomes chronic and may spread to internal genital organs leading to pelvic inflammatory disease and eventually to infertility. Chronic form of infection may necessitate tissue destruction to prevent the development of dysplasia and neoplasm. Various methods such as electrocautery, loop diathermy, cryotherapy or laser are used to destroy the inflamed area. In this study we present 26 cases of chronic cervicitis managed with Nd-YAG laser with a success rate of 93%. We advice this method to block the development of cervical intraepithelial neoplasm.