Early versus late amniotomy for labour induction: a randomized controlled trial.

OBJECTIVE: To evaluate the impact of early vs. late amniotomy on delivery mode in women undergoing induction of labor. STUDY DESIGN: 143 women admitted for induction were randomized to early amniotomy (EA, concomitant with the beginning of oxytocin infusion; n = 71) or to late amniotomy (LA, four hours after the beginning of oxytocin; n = 72). Randomization was stratified by parity. The primary outcome was the rate of cesarean. Secondary outcomes were duration of labor and intrapartum fever. RESULTS: The cesarean rate was similar between groups (18% vs. 17% among nulliparous; and 3% vs. 0% among parous women, in EA and LA group, respectively). However, EA was associated with shorter oxytocin-to-delivery interval (12 vs. 15 h) and a non-significant decrease in intrapartum fever (3% vs. 25%) than LA in nulliparous women (p = 0.05). CONCLUSION: For women undergoing oxytocin induction, early amniotomy is associated with shorter labor in nulliparous women with no effect on the risk of cesarean section in both nulliparous and multiparous women.

Laryngeal chemoreflexes induced by acid, water, and saline in nonsedated newborn lambs during quiet sleep.

Laryngeal chemoreflexes (LCR) are triggered by the contact of assorted liquids with the laryngeal mucosa. In the neonatal period, the immature LCR consist primarily of apnea and bradycardia, which at times can be life threatening. The aim of this study was to assess LCR induction in nonsedated, newborn full-term lambs by several acid solutions, compared with distilled water and saline. Twelve lambs were instrumented for recording of glottal adductor and diaphragm EMG, EEG, eye movements, heart rate, systemic arterial pressure, and respiratory movements. LCR were induced during quiet sleep by the injection (0.5 ml) of saline, distilled water or two acid solutions (HCl and citric acid, pH 2, diluted in either water or saline). A chronic supraglottal catheter was used to inject the solutions in a random order. Distilled water and acid solutions did not induce any significant decrease in heart rate or respiratory rate. However, significant lower airway protective responses (swallowing, cough, and arousal) were observed after distilled water and especially acid solution administration. In conclusion, LCR in full-term lambs, particularly with acid solutions, are merely characterized by lower airway protective responses resembling mature LCR reported in adult mammals.