Membrane sweeping for induction of labour.

BACKGROUND: Induction of labour involves stimulating uterine contractions artificially to promote the onset of labour. There are several pharmacological, surgical and mechanical methods used to induce labour. Membrane sweeping is a mechanical technique whereby a clinician inserts one or two fingers into the cervix and using a continuous circular sweeping motion detaches the inferior pole of the membranes from the lower uterine segment. This produces hormones that encourage effacement and dilatation potentially promoting labour. This review is an update to a review first published in 2005. OBJECTIVES: To assess the effects and safety of membrane sweeping for induction of labour in women at or near term (≥ 36 weeks' gestation). SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register (25 February 2019), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (25 February 2019), and reference lists of retrieved studies. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing membrane sweeping used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed on a predefined list of labour induction methods. Cluster-randomised trials were eligible, but none were identified. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion, risk of bias and extracted data. Data were checked for accuracy. Disagreements were resolved by discussion, or by including a third review author. The certainty of the evidence was assessed using the GRADE approach. MAIN RESULTS: We included 44 studies (20 new to this update), reporting data for 6940 women and their infants. We used random-effects throughout. Overall, the risk of bias was assessed as low or unclear risk in most domains across studies. Evidence certainty, assessed using GRADE, was found to be generally low, mainly due to study design, inconsistency and imprecision. Six studies (n = 1284) compared membrane sweeping with more than one intervention and were thus included in more than one comparison. No trials reported on the outcomes uterine hyperstimulation with/without fetal heart rate (FHR) change, uterine rupture or neonatal encephalopathy. Forty studies (6548 participants) compared membrane sweeping with no treatment/sham Women randomised to membrane sweeping may be more likely to experience: · spontaneous onset of labour (average risk ratio (aRR) 1.21, 95% confidence interval (CI) 1.08 to 1.34, 17 studies, 3170 participants, low-certainty evidence). but less likely to experience: · induction (aRR 0.73, 95% CI 0.56 to 0.94, 16 studies, 3224 participants, low-certainty evidence); There may be little to no difference between groups for: · caesareans (aRR 0.94, 95% CI 0.85 to 1.04, 32 studies, 5499 participants, moderate-certainty evidence); · spontaneous vaginal birth (aRR 1.03, 95% CI 0.99 to 1.07, 26 studies, 4538 participants, moderate-certainty evidence); · maternal death or serious morbidity (aRR 0.83, 95% CI 0.57 to 1.20, 17 studies, 2749 participants, low-certainty evidence); · neonatal perinatal death or serious morbidity (aRR 0.83, 95% CI 0.59 to 1.17, 18 studies, 3696 participants, low-certainty evidence). Four studies reported data for 480 women comparing membrane sweeping with vaginal/intracervical prostaglandins There may be little to no difference between groups for the outcomes: · spontaneous onset of labour (aRR, 1.24, 95% CI 0.98 to 1.57, 3 studies, 339 participants, low-certainty evidence); · induction (aRR 0.90, 95% CI 0.56 to 1.45, 2 studies, 157 participants, low-certainty evidence); · caesarean (aRR 0.69, 95% CI 0.44 to 1.09, 3 studies, 339 participants, low-certainty evidence); · spontaneous vaginal birth (aRR 1.12, 95% CI 0.95 to 1.32, 2 studies, 252 participants, low-certainty evidence); · maternal death or serious morbidity (aRR 0.93, 95% CI 0.27 to 3.21, 1 study, 87 participants, low-certainty evidence); · neonatal perinatal death or serious morbidity (aRR 0.40, 95% CI 0.12 to 1.33, 2 studies, 269 participants, low-certainty evidence). One study, reported data for 104 women, comparing membrane sweeping with intravenous oxytocin +/- amniotomy There may be little to no difference between groups for: · spontaneous onset of labour (aRR 1.32, 95% CI 88 to 1.96, 1 study, 69 participants, low-certainty evidence); · induction (aRR 0.51, 95% CI 0.05 to 5.42, 1 study, 69 participants, low-certainty evidence); · caesarean (aRR 0.69, 95% CI 0.12 to 3.85, 1 study, 69 participants, low-certainty evidence); · maternal death or serious morbidity was reported on, but there were no events. Two studies providing data for 160 women compared membrane sweeping with vaginal/oral misoprostol There may be little to no difference between groups for: · caesareans (RR 0.82, 95% CI 0.31 to 2.17, 1 study, 96 participants, low-certainty evidence). One study providing data for 355 women which compared once weekly membrane sweep with twice-weekly membrane sweep and a sham procedure There may be little to no difference between groups for: · induction (RR 1.19, 95% CI 0.76 to 1.85, 1 study, 234 participants, low-certainty); · caesareans (RR 0.93, 95% CI 0.60 to 1.46, 1 study, 234 participants, low-certainty evidence); · spontaneous vaginal birth (RR 1.00, 95% CI 0.86 to 1.17, 1 study, 234 participants, moderate-certainty evidence); · maternal death or serious maternal morbidity (RR 0.78, 95% CI 0.30 to 2.02, 1 study, 234 participants, low-certainty evidence); · neonatal death or serious neonatal perinatal morbidity (RR 2.00, 95% CI 0.18 to 21.76, 1 study, 234 participants, low-certainty evidence); We found no studies that compared membrane sweeping with amniotomy only or mechanical methods. Three studies, providing data for 675 women, reported that women indicated favourably on their experience of membrane sweeping with one study reporting that 88% (n = 312) of women questioned in the postnatal period would choose membrane sweeping in the next pregnancy. Two studies reporting data for 290 women reported that membrane sweeping is more cost-effective than using prostaglandins, although more research should be undertaken in this area. AUTHORS' CONCLUSIONS: Membrane sweeping may be effective in achieving a spontaneous onset of labour, but the evidence for this was of low certainty. When compared to expectant management, it potentially reduces the incidence of formal induction of labour. Questions remain as to whether there is an optimal number of membrane sweeps and timings and gestation of these to facilitate induction of labour.

The effect of suction method, catheter size, and suction pressure on lung volume changes during endotracheal suction in piglets.

We aimed to identify the effect of suction pressure and catheter size on change in lung volume during open and closed endotracheal suction. Anesthetized piglets (n = 12) were intubated with a 4.0-mm endotracheal tube. Lung injury was induced with saline lavage. Three suction methods (open, closed in-line, and closed with a side-port adaptor) were performed in random order using 6, 7, and 8 French gauge (FG) catheters, at vacuum pressures of 80, 140, and 200 mm Hg. Lung volume change was measured with respiratory inductive plethysmography. Overall, open suction resulted in greater lung volume loss during and at 60-s postsuction than either closed method (p < 0.001). When open and closed methods were analyzed separately, volume change was independent of catheter size and suction pressure with open suction. With closed suction, volume loss increased with larger catheter sizes and higher suction pressures (p < 0.001). With an 8-FG catheter and suction pressure of 140 or 200 mm Hg, volume loss was equivalent with open and closed suction. Lung volume changes are influenced by catheter size and suction pressure, as well as suction method. With commonly used suction pressures and catheter sizes, closed suction has no advantage in preventing loss of volume in this animal model.