Cup Detachment Research Articles

Vacuum-assisted delivery outcomes: is advanced maternal age a factor?

This study evaluated age-related maternal outcomes of vacuum-assisted vaginal deliveries (VAD). This retrospective cohort study included all nulliparous women with singleton VAD in one academic institution. Study group parturients were maternal age ≥ 35years and controls < 35. Power analysis revealed that 225 women/group would be sufficient to detect a difference in the rate of third- and fourth-degree perineal tears (primary maternal outcome) and umbilical cord pH < 7.15 (primary neonatal outcome). Secondary outcomes were maternal blood loss, Apgar scores, cup detachment, and subgaleal hematoma. Outcomes were compared between groups. From 2014 to 2019, 13,967 nulliparas delivered at our institution. Overall, 8810 (63.1%) underwent normal vaginal delivery, 2432 (17.4%) instrumental, and 2725 (19.5%) cesarean. Among 11,242 vaginal deliveries, 10,116 (90%) involved women < 35, including 2067 (20.5%) successful VAD vs. 1126 (10%) women ≥ 35years with 348 (30.9%) successful VAD (p < 0.001). Rates of third- and fourth-degree perineal lacerations were 6 (1.7%) with advanced maternal age and 57 (2.8%) among controls (p = 0.259). Cord pH < 7.15 was similar: 23 (6.6%) study group and 156 (7.5%) controls (p = 0.739). Advanced maternal age and VAD are not associated with higher risk for adverse outcomes. Older, nulliparous women are more likely to undergo vacuum delivery than younger parturients.

Can We Predict Feto-Maternal Adverse Outcomes of Vacuum Extraction?

Introduction Vacuum extraction (VE) is an important modality in modern obstetrics, yet sometimes results in maternal or neonatal adverse outcomes, which can cause a lifetime disability. We aimed to characterize potential risk factors for adverse outcomes that in retrospect would have led the physician to avoid the procedure. Materials and Methods Retrospective cohort of 3331 singleton pregnancies, ≥34w delivered by VE. 263 deliveries (7.9%) incurred a VE-related feto-maternal adverse outcome, defined as one or more of the following: 3-4th-degree perineal laceration, subgaleal hematoma, intracranial hemorrhage, shoulder dystocia, clavicular fracture, Erb's palsy or fracture of humerus. 3068 deliveries (92.1%) did not have VE-related adverse outcomes. Both groups were compared to determine potential risk factors for VE adverse outcomes. Results Multivariable regression found seven independent risk factors for VE-related feto-maternal adverse outcomes: Nulliparity - with an odds ratio (OR) of 1.82 (95% CI=1.11-2.98, p=0.018), epidural anesthesia (OR 1.99, CI=1.42-2.80, p<0.001), Ventouse-Mityvac (VM) cup (OR 1.86, CI=1.35-2.54, p<0.001), prolonged second stage as indication for VE (OR 1.54, CI=1.11-2.15, p=0.010), cup detachment (OR 1.66, CI=1.18-2.34, p=0.004), increasing procedure duration (OR 1.07 for every additional minute, CI=1.03-1.11, p<0.001) and increasing neonatal birthweight (OR 3.42 for every additional kg, CI=2.33-5.02, p<0.001). Occiput anterior (OA) position was a protective factor (OR 0.62, CI=0.43-0.89, p=0.010). Conclusions VE-related adverse outcomes can be correlated to clinical characteristics, such as nulliparity, epidural anesthesia, VM cup, prolonged second stage as indication for VE, cup detachment, prolonged procedure duration and increasing neonatal weight. OA position was a protective factor. This information may assist medical staff to make an informed decision whether to choose VE or cesarean delivery (CD).

Head position and vacuum-assisted delivery using the Kiwi Omnicup.

To evaluate the association between fetal head position during prevacuum assessment and adverse outcomes. This retrospective cohort study included all vacuum-assisted deliveries using the Kiwi Omnicup over 5 years. Primary outcomes were third- or fourth-degree perineal tear, pH < 7.1, and subgaleal hematoma (SGH). AGAR, neonatal intensive care unit admission, cephalohematoma, Erb's palsy, third-stage duration, and postpartum hemorrhage were secondary. Outcomes were compared between the occiput posterior (OP) and occiput anterior (OA) positions. The study included 1960 patients. OP position was more likely to involve epidural analgesia (311 [82.5%] vs. 1216 [77%], P= 0.020), higher fetal head station (P= 0.001), higher percentage of cup detachments (121 cases [32.1%] vs. 307 [19.4%], P= 0.001), and longer procedure (5.5 ± 3.7 min vs. 4.7 ± 2.8 min, P= 0.001). OP was associated with umbilical cord pH< 7.1 (21 [5.5%] vs. 52 [3.9%], P= 0.032), NICU admissions (16 [4.2%] vs. 38 [2.4%], P= 0.049), SGH (18 [4.8%] vs. 38 [2.4%], P= 0.013), and high-degree perineal tears (12 [3.2%] vs. 26 [1.7%], with borderline significance, P= 0.051). SGH and high-grade tears remained significantly associated with OP position (P= 0.008 and P= 0.016, respectively) after adjusting for maternal age, nulliparity, diabetes, epidural anesthesia, preprocedure head station, and birth weight. OP position is an independent risk-factor for anal sphincter injury and SGH during vacuum-assisted delivery.

The teat cup detachment level affects milking performance in an automatic milking system with teat cleaning and milking in the same teat cup.

The goal of the present study was to determine the best quarter milk flow for teat cup detachment depending on lactational stage and milking interval to optimize the milking process in automatic milking systems (AMS). Milking characteristics and post-milking teat condition were recorded in an AMS with all actions from teat cleaning to post-milking teat dipping occurring in the same teat cup and liner (GEA DairyRobot R9500). In 24 dairy cows, 12 in early (<80 DIM) and 12 in late lactation (>180 DIM), 294 milkings were recorded during 12 consecutive days. Teat cup detachment was set at a quarter milk flow of 50, 87.5 or 125 g/min. Voluntary milking intervals varied similarly in cows in early (6.1-14.8 h) and late lactation (6.3-15.7 h). Total milk yield, milk production per h and average milk flow were higher in early than in late lactation cows. Total milk yield per milking did not differ between detachment levels. The mean milking time was reduced by up to 1.5 min at the highest compared to the lowest detachment level mainly in early lactation cows (P < 0.05). However, no significant effect of the detachment level on milking time was observed at milking intervals >10 h. Average milk flow was higher at milking intervals >10 h than ≤10 h (P < 0.05). In the early lactation cows (only) the average milk flow increased with higher detachment levels (P < 0.05). Teat condition did not differ among detachment settings or milking intervals. In conclusion, teat cup detachment up to 125 g/min reduces milking time in both early and late lactation without a loss of milk yield or affecting the teat condition. Combined with a higher average milk flow through avoiding too short milking intervals, the total milking time and hence stall occupancy can be optimized by early teat cup detachment.

Vacuum assisted delivery outcomes. Does advanced maternal age matter?

This study evaluated whether advanced maternal age during vacuum-assisted delivery (VAD) leads to a higher rate of adverse maternal and neonatal outcomes. This retrospective cohort study included all nulliparous women who underwent a singleton, VAD in our institution, from 2014 through 2019. The women were grouped according to maternal age ≥ 35 in the study group and < 35 in the control group. Power analysis calculation determined that a sample size of at least 225 women in each group was sufficient to detect significant differences between groups in the rate of third- and fourth-degree perineal tears and umbilical cord pH < 7.15. primary maternal outcomes were third- and fourth-degree perineal tears. primary neonatal outcomes were umbilical cord pH < 7.15. Secondary outcomes were maternal blood loss, Apgar scores, cup detachment, and subgaleal hematoma. Outcomes were compared between the two groups. During the study period, 13,967 nulliparous women delivered in our institution, including 8,810 (63.1%) spontaneous vaginal deliveries, 2,432 (17.4%) instrumental deliveries and 2,725 (19.5%) cesarean sections. The rate of operative vaginal delivery was higher in the advanced maternal age group. Among the vaginal deliveries, 10,116 (90%) were to women < 35, with 2,067 (20.5%) successful vacuum-assisted delivery VAD, and 1,126 (10%) were to women ≥35 years, with 348 (30.9%) successful VAD. There were no significant differences in the rates of third and fourth-grade perineal lacerations or lower cord pH between the study groups. Although there was no difference in the indications for the procedure between the groups, advanced maternal age was associated with a higher head station during the pre-procedure assessment (p=0.002). Vacuum-assisted delivery is not associated with a higher risk for adverse maternal or neonatal outcomes among women with advanced maternal age.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Adverse outcomes in vacuum-assisted delivery after detachment of non-metal cup: a retrospective cohort study.

To evaluate neonatal and maternal outcomes associated with detachment of non-metal vacuum cup during delivery and to identify risk factors for these detachments. This retrospective cohort study included women with singleton pregnancy, who underwent vacuum-assisted vaginal delivery with a non-metal vacuum cup in a single academic institution, January 2014-August 2019. Failed vacuum deliveries were excluded. Primary outcomes were defined as subgaleal hematoma (SGH) and cord blood pH < 7.15. Secondary outcome included other neonatal complications and adverse maternal outcomes. Outcomes were compared between vacuum-assisted deliveries with and without cup detachment during the procedure. A total of 3246 women had successful VAD and met the inclusion criteria. During the procedure, the cup detached at least once in 665 (20.5%) deliveries and did not detach in 2581 (79.5%). The cup detachment group experienced higher rates of SGH (8.9% vs. 3.5%, p = 0.001) and cord blood pH < 7.15 (9.8% vs. 7.1%, p = 0.03). There were also more neonatal intensive care unit admissions (NICU) (4.4% vs. 2.7%, p = 0.03) and more fetuses with occiput posterior position (70.8% vs. 79.4%, p = 0.001), the vacuum duration was slightly longer (6 ± 3.7 vs. 5 ± 2.9min) and more neonates had birth weights > 3700g (14.1% vs, 10.3%, p = 0.006). Interestingly, there were more males in that group (60.6 vs. 54.6, p = 0.005). All these factors remained significant after controlling for potential confounders. Vacuum cup detachment has several predictive characteristics and is associated with adverse neonatal outcomes that should be incorporated into decisions made during the procedure.

Infected hip prosthesis in patient with suspected Covid-19 infection

BackgroundInfections following arthroplasty are one of the major risks during this type of surgery. Moreover, the outbreak of coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus Disease 2), has developed into an unprecedented pandemic, posing enormous pressure on health-care providers around the world.Case presentationFour and half years after right hip arthroplasty, the patient came back to our attention with pain at the same hip. The instrumental examinations showed signs of cup detachment. After carefully analyzing the case, we decided to perform a sterile aspiration of the hip in the operating room under C-arm fluoroscopy. Microbiological examinations showed positivity for E. coli. The patient underwent surgery by which the prosthesis was removed and a spacer was implanted. A therapy with Cefotaxim 2 g three times a day for 6 weeks was then set, and then a total arthroplasty was performed. During this period, the COVID-19 pandemic occurred and therefore the patient received nasal-throat swabbing two times, and both yielded negative results. However, 1 week after the final surgery, his respiratory conditions deteriorated and chest X-ray and CT scan showed images of ground-glass opacification patterns (GGO). Due to the clinical symptoms and the characteristic images of the instrumental examinations, the patient was transferred to an observation ward. Thereafter, two more swab tests gave negative results. The patient was then transferred to the ward for patients with typical symptoms of COVID-19 but with negative swab tests for 2 weeks and was subsequently discharged home.ConclusionThe purpose of this case report was to point out the correct treatment of a PJI after the outbreak of COVID-19. Despite the ongoing COVID-19 pandemic, the guidelines in the case of periprosthetic hip infection further confirmed the correct management of the patient.

Association of traction force and adverse neonatal outcome in vacuum-assisted vaginal delivery: A prospective cohort study.

Traction force is a possible risk factor for adverse neonatal outcome in vacuum extraction delivery, but the knowledge is scarce and further investigation is needed. Our hypothesis was that high-level traction force increases the risk of admission to the neonatal intensive care unit. The study was a hospital-based prospective cohort study on low- and mid-vacuum extractions at the labor and delivery ward, Karolinska University Hospital, Huddinge, Sweden. Traction forces were measured in 331 women. An electronical handle was used to measure and register traction force. The main exposure variable was high-level traction force (≥75th percentile) during the first three pulls and the primary outcome was admission to the neonatal intensive care unit. Logistic regression was used to estimate the adjusted risk. Among the exposed, 14/84 (16.7%) were admitted to neonatal intensive care, and among the unexposed 10/247 (4%). The crude odds ratio (OR) of admission to the neonatal intensive care unit when exposed to high-level traction force was 4.7, and the adjusted (birthweight, gestational length, cup detachment, number of pulls, duration, duration >15minutes, mid-cavity fetal head station, failed extraction, indication and parity) OR was 2.85 (95% confidence interval [CI] 1.09-7.48). No significant effect was seen in Apgarscores <7 at 5minutes or pH<7.1. High-level traction force may be a risk factor for neonatal complications. Although these results do not mandate any alterations in clinical guidelines, perioperative feedback on traction force may be useful to alert the obstetrician to a timely conversion to cesarean section. To study plausible traction force specific outcomes such as head traumas, a larger sample size is required.

Effect of team training and monitoring on the rate of failed mid and low cavity vacuum extraction: a hospital based intervention study

BackgroundClinical team training has been advocated as a means to improve delivery care, and failed extractions is a suggested variable for clinical audit in instrumental vaginal delivery.Other activities may also have intended or unintended effects on care processes or outcomes.MethodsWe retrospectively observed 1074 mid and low vacuum extraction deliveries during three time periods (prevalence periods): Baseline (period 0), implemented team training (period 1 and 2) and monitoring of traction force during vacuum extraction (period 2). Our primary outcome was failed extraction followed by emergency cesarean section or obstetric forceps delivery.ResultsThe prevalence proportion (relative risk) of failed extraction decreased significantly after implementation of team training, from 19% (period 0) to 8 % (period 1), corresponding to a relative risk of 0.48 [0.26–0.87]. The secondary procedural outcome complicated delivery (duration > 15 min or number of pulls > 6, or cup detachment > 1) was decreased in period 2 compared to period 1, RR 0.42 [0.23–0.76]. Secondary clinical (neonatal) outcome were not affected.ConclusionClinically based educational efforts and increased monitoring improved procedural outcome without improving neonatal outcome. The study design has inherent limitations in making causal inference.

Protracted vacuum extraction and neonatal intracranial hemorrhage among infants born at term: a nationwide case-control study.

The association between vacuum extraction and intracranial hemorrhage has been debated. We sought to investigate the impact of protracted vacuum extraction on the risk for neonatal intracranial hemorrhage in term infants. This nationwide case-control study covered Swedish maternity wards from 1999 to 2013. All term, live-born infants diagnosed with neonatal intracranial hemorrhage after vacuum-assisted delivery were included as cases (n=167). For each case, 3 vacuum-delivered controls, without a diagnosis for intracranial hemorrhage, were selected (n=546 controls). Conditional logistic regression analysis was used to study the association between protracted extraction (defined as vacuum duration >15min, >6 pulls or >2 cup detachments), and neonatal intracranial hemorrhage. Extractions exceeded 15min among 33% of the cases, vs 5% of the controls. More than six pulls were used in 25% of the cases and in 4% of the controls, and more than two cup detachments occurred in 3.6% of the cases and in 0.6% of the controls. Compared with extractions adhering to safety recommendations, the odds for intracranial hemorrhage were nine-fold (OR 8.91, 95%, CI 5.22-15.20) among infants exposed to a protracted extraction. After adjustments for potential confounders, the OR decreased to 8.04 (95% CI 4.49-14.38). The strong association between protracted extraction and intracranial hemorrhage suggests that adherence to safety recommendations may reduce the risk for intracranial hemorrhage in infants delivered by vacuum extraction. However, safe limits for vacuum duration and number of pulls are still unknown and intracranial hemorrhage may occur even when performed in accordance with safety recommendations.

Cup detachment during vacuum-assisted vaginal delivery and birth outcome.

To determine the perinatal outcome associated with cup detachment during vacuum-assisted vaginal delivery (VAVD). A retrospective cohort study of all women attempting VAVD in a tertiary hospital (2012-2014). Singleton-term pregnancies were included. Antepartum fetal death and major fetal structural or chromosomal abnormalities were excluded. Primary outcome was neonatal birth trauma (subgaleal hematoma, subarachnoid hematoma, subdural hematoma, skull fracture, and/or erb's palsy). Secondary outcomes were maternal complications or other neonatal morbidities. Outcomes were compared between women after ≥1 cup detachment (study group) and the rest (control group). Logistic regression analysis was utilized to adjust results to potential confounders. Overall, 1779 women attempted VAVD during study period. Of them, in 146 (8.2%), the cup detached prior to delivery; 130/146 (89%) had a single detachment. After detachment, 4 (2.7%) delivered by cesarean section, 77 (52.7%) delivered after cup reapplication, and 65 (44.6%) delivered spontaneously. Women in the study group were more likely to undergo VAVD due to prolonged second stage, and were characterized by lower rates of metal cup use. Neonates in the detachment group had higher rates of subarachnoid hematoma and composite neonatal birth trauma (2.7 vs. 0.1% and 4.8 vs. 1.8%, respectively, p<0.05). This remained significant after adjustment to potential confounders (subarachnoid hematoma aOR=45.44, 95% CI 6.42-321.62 and neonatal birth trauma aOR=2.62, 95% CI 1.1-6.22, p<0.05 for all). Other neonatal and maternal morbidities were similar between groups. Cup detachment is associated with a higher rate of adverse neonatal outcome. Cup reapplication should be considered carefully.

Neonatal complications among 596 infants delivered by vacuum extraction (in relation to characteristics of the extraction)

Objective: To investigate the association between complicated vacuum extraction (VE) deliveries and neonatal complications.Methods: Observational study including data on the management of 596 consecutive VE-deliveries at 6 different birth clinics in Sweden in 2013. We used logistic regression to examine the association between a complicated VE and: extracranial bleeding, severe neonatal complication (intracranial hemorrhage and/or asphyxia/low Apgar score and/or convulsions, and/or encephalopathy), and brachial plexus injury. VE was considered complicated if duration exceeded 15 min, and/or more than six pulls were used, and/or more than one cup detachment occurred. Uncomplicated VE served as the reference group.Results: Ten percent of the infants were diagnosed with at least one of the investigated complications. Cephalohematoma occurred in 5.2% of the infants and 1.5% had a subgaleal hematoma. Altogether 24 (4.0%) infants were diagnosed with a severe complication; low Apgar score, neonatal convulsions, encephalopathy or intracranial hemorrhages. Brachial plexus injury occurred in eight (1.3%) infants. The crude odds ratio for extracranial hemorrhages was 2.6 (95% CI 1.17–5.77), 4.07 (1.67–9.92) for severe neonatal complications, and 4.63 (1.08–19.76) for brachial plexus injury.Conclusions: Extraction time >15 min, >6 pulls and >1 cup detachment is associated with increased risk of neonatal complications. These results support compliance with guidelines and recommendations for VE deliveries.

Neonatal complications in vacuum-assisted vaginal delivery: are they associated with number of pulls, cup detachments, and duration of vacuum application?

To explore whether the characteristics of vacuum delivery are associated with the occurrence of head injury and neonatal complications. Retrospectively cohort study of vacuum-assisted attempted vaginal deliveries of singletons. We studied the association of total duration of vacuum application and number of pulls and cup dislodgement with (1) primary outcome: the occurrence of major (subgaleal hemorrhage, skull fracture, and intracranial hemorrhage) or minor (cephalohematoma, scalp laceration more extensive than simple abrasions) neonatal head injuries and (2) secondary outcome: the occurrence of neonatal complications, including 5-min Apgar score<7, umbilical artery pH<7.10, shoulder dystocia, or need for neonatal intensive care unit admission. Logistic regression analysis was used to control for confounders. Vacuum-assisted delivery was attempted in 555 women. It was successful in 515 cases, and it failed in 40 (7.2%). Head injury occurred in 32 (6.2%) of vaginally delivered neonates, and it was related to duration of vacuum application (P=0.004) and birth weight (P=0.048). However, the associations lost a statistical significance at the multivariate analysis. Neonatal complications occurred in 25 cases (5%), and they were associated with meconium-stained amniotic fluid (P<0.001) and duration of vacuum application (P=0.03) at the multivariate analysis. However, most of the complications were actually associated with the need for vacuum delivery rather than the procedure itself. Neonatal head injury after vacuum application is not independently related to total duration of vacuum application, number of pulls, or cup dislodgements.

Documentation of instrumental vaginal deliveries: The benefits of a pro forma.

Instrumental vaginal deliveries (IVDs) account for approximately 11% of births in Australia. Complications resulting from IVD can occasionally be the subject of litigation. The Royal College of Obstetricians and Gynaecologists suggests a standardised pro forma in their guidelines as an aid to accurate and complete IVD documentation. Many units, including ours, use less structured reporting, which is probably also less adequate. To assess whether the introduction of a dedicated IVD form improves the quality of IVD documentation. Analysis of the quality of IVD documentation before and after the implementation of a new dedicated IVD form. A survey to evaluate clinicians' opinion on the new standardised form. Significant improvement was found in documentation of key information including the documentation of caput (p < 0.05), type of instrument, number of ventouse cup detachments, moulding of specific sutures, abdominal palpation (number of fifths of foetal head palpable), liquor colour and total time of instrument application (p < 0.001). A majority of clinicians believed the form to be beneficial in terms of completeness and that it reduced the amount of time required for documentation. IVD documentation is enhanced by the use of a dedicated form. Clinical judgement may also be enhanced by the discipline involved in the formal assessment required by the form.

Obstetric management in vacuum-extraction deliveries

ObjectiveThe aim of this observational study was to describe the obstetric management in vacuum extraction (VE) deliveries and to compare these findings to instructions in clinical guidelines on VE. MethodsIn 2013, detailed data on management of 600 VE cases were consecutively collected from six different delivery units in Sweden. Each unit also contributed their own clinical VE guideline. ResultsIn total, 93% of the VEs ended with a vaginal delivery while 7% failed and were converted to an emergency cesarean section. In 2.3% extraction time exceeded 20 minutes, and in 6% more than six pulls were used to deliver the fetus. Cup detachment occurred in 14.6%, and fundal pressure was used in 11% of the deliveries. In 2.3%, fetal station was assessed as above the level of the maternal ischial spines. The clinical guidelines on VE varied in scope and content between units, and were often incomplete according to best practice. ConclusionThe vast majority of the VEs were conducted in accordance with safety recommendations. However, in a few extractions, safety rules were disregarded and more than six pulls or an extraction time of more than 20 minutes were used to complete the delivery.

The association between fetal head position prior to vacuum extraction and pregnancy outcome.

To estimate the association of fetal head position prior to vacuum extraction (VE) and pregnancy outcome. A retrospective cohort study of singleton pregnancies who underwent VE. Pregnancy outcome of occipito-anterior (OA) position of the fetal head was compared to those with occipito-posterior (OP) position. Amongst overall 12,063 women undergoing trial of labor, there were 1118 (9.2%) VE deliveries. Of them, 871 (77.9%) had OA and 247 (22.1%) had OP position of the fetal head. Except for a higher rate of nulliparity in the OA group, no significant differences between the groups regarding pregnancy complications and birthweight were noted. In the OP group, there were higher rates of prolonged 2nd-stage of labor as an indication for VE (49.8 vs. 36.5%, p < 0.001) and single detachment of vacuum cup (11.3 vs. 6.7%, p = 0.02) without any increased risk of failed extraction. Higher risks for sub-galeal hematoma (aOR = 4.36, p = 0.03) and low 5-min Apgar score (aOR = 4.63, p = 0.02) were observed in the OP group with otherwise similar rates of adverse maternal and neonatal outcomes. Among women undergoing VE, OP position is associated with higher rate of vacuum cup detachment, low 5-min Apgar score and increased risk for sub-galeal hematoma with otherwise similar rates of adverse maternal and neonatal outcomes.

Risk factors for anal sphincter tears in vacuum-assisted delivery

ObjectiveThe aim of the present study was to describe the prevalence of anal sphincter tears (AST) in relation to obstetric management and technique during vacuum extraction deliveries (VE) (re: indications, the station of the fetal head at application of the cup, number of tractions, the length for the extraction, cup detachments, pain relief, episiotomy, fetal presentation, and experience of the operator) as well as maternal and infant anthropometrics. MethodsDescriptive study. Data on six hundred vacuum extraction deliveries were consecutively collected from six different delivery units in Sweden. Each unit contributed with data on 100 deliveries. The final study population included 596 women who delivered by vacuum extraction. ResultsThere was no correlation between the management of the vacuum extraction and risk for anal sphincter tear. Women from Africa had nearly a fourfold risk for anal sphincter tear during vacuum-assisted delivery compared with Swedish-born women (OR 3.82 CI 1.47–9.89). Compared with infants with birth weight less than 4000 g, birth weight above 4000 g was associated with increased risk of AST (OR 1.87 CI 1.06–3.28). ConclusionsIn this study, the obstetric management in VE-assisted deliveries did not impact the risk of AST.

Comparison of Obstetric Efficacy and Safety of the Kiwi OmniCup with Conventional Vacuum Extraction.

Purpose: The aim of the present study was to compare the safety and efficacy of the Kiwi OmniCup system with conventional vacuum delivery. Methods: A retrospective study of operative vaginal deliveries was done for 4682 births. The procedures included 217 operative vaginal deliveries (4.6 %), 79 of which were done using conventional vacuum extraction (37 %) and 138 using the Kiwi system (63 %). Results: Use of the Kiwi system was associated with a significant reduction in episiotomies (61 vs. 76 % in the control group; p < 0.05). The rates of successful completion of birth were comparable for the two systems (94 % with the Kiwi system and 99 % with conventional vacuum delivery). Cup detachment occurred significantly more often in the Kiwi group (p < 0.005), requiring a change to a different method of birth significantly more often. It was necessary to change the procedure significantly more often from the mid-pelvis (p < 0.05). The incidence of maternal and foetal injuries was similar for the two systems. Conclusions: With regard to obstetric efficacy and safety and foetal and maternal injuries, the Kiwi system is an acceptable alternative to the conventional vacuum cup. The advantages of the Kiwi system are its significantly lower episiotomy rate and its ease and rapidity of use.

Rapid versus stepwise application of negative pressure in vacuum extraction-assisted vaginal delivery: a multicentre randomised controlled non-inferiority trial

To evaluate whether the application of rapid negative pressure for vacuum-assisted delivery is as effective and safe as the stepwise method. Randomised controlled trial. Six centres, including university, secondary and tertiary hospitals, in Thailand. In total, 662 women were randomised to rapid and stepwise groups, with 331 women in each group. Vacuum extraction was performed by applying a metal cup (Malmstrom) connected to an electric pump to the fetal head. The stepwise method consisted of four incremental steps of 0.2 kg/cm² every 2 minutes to obtain a final negative pressure of 0.8 kg/cm². In the rapid method the negative pressure of 0.8 kg/cm² was applied in one step in < 2 minutes. Success rate of vacuum extraction, vacuum cup detachment rate, duration of vacuum extraction, and maternal and neonatal complications. There were no significant differences in detachment rates (RD 0.3%, 95% CI -3.1 to 2.4). The overall success rates were identical, at 98.2%. There were significant reductions in the time between applying the vacuum cup and attaining maximum negative pressure (MD -4.6 minutes; 95% CI -4.4 to -4.8 minutes), and in the time between applying the cup and delivery (MD -4.4 minutes; 95% CI -4.8 to -4.0 minutes). There was a significantly higher rate of perineal suture in the rapid method group (RD 4.5%; 95% CI 1.1-8.2). There were no significant differences in maternal and fetal morbidities. Rapid negative pressure vacuum extraction could be performed as effectively and safely as the stepwise method, in a shorter period of time.

Étude comparative de deux ventouses à usage unique

To compare the effectiveness of two single-use vacuum devices, the Kiwi Omnicup and the Mitysoft Bell. This retrospective study was conducted during two different periods: from January 15th to March 14th to assess the Kiwi Omnicup and from March 15th to June 15th for the Mitysoft Bell. The primary outcome was the successful completion of delivery with the allocated instrument. Secondary outcomes were fetal scalp trauma and maternal perineal lesions. All deliveries were performed by similar teams. Thirty-nine patients were included in the Kiwi Omnicup group and 48 in the Mitysoft Bell group. Compared to the Kiwi Omnicup, the Mitysoft Bell was associated with a greater number of cup detachments (41.7% vs. 10.3%; p<0.01) and a significantly higher rate of failure (31.3% vs. 12.8%). Rates of substantial scalp trauma and maternal trauma were similar in both groups. The Mitysoft Bell is not as successful at achieving a vaginal delivery as the Kiwi Omnicup. This could be explained by the shape of the cup.