Cohort study of silastic obstetric vacuum cup deliveries: I. Safety of the instrument

A prospective study was undertaken to determine the safety of the Silastic vacuum extractor. Between November 1982 and July 1983, a cohort of 84 successful vacuum extractor deliveries was examined, using the next sequential forceps delivery and spontaneous vaginal delivery as controls. In addition to routine neonatal morbidity measures, Scanlon early neonatal neurobehavioral scale and a modified Sarnat encephalopathy staging examination were used to critically assess neurologic functioning; a cranial ultrasound scan was performed to look for intracerebral hemorrhage, and an indirect ophthalmologic examination was done to assess the incidence of retinal hemorrhage. The study yielded no significant increase in maternal vaginal trauma for vacuum extractor versus spontaneous vaginal delivery, but there was a significantly greater incidence for forceps delivery (60%) versus vacuum extractor (25%) and more associated blood loss for forceps delivery (P less than .01). There was no significant increase in neonatal morbidity for vacuum extractor compared with forceps delivery nor in serious morbidity compared with spontaneous vaginal delivery. Specifically, for vacuum extractor versus forceps delivery there was no difference in one- and five-minute Apgar scores, extent of resuscitation, cosmetic injury, jaundice, mean neonatal intensive care unit stay, or incidence of retinal hemorrhage. Notably, there was no mortality related to delivery method, but there were two unrelated deaths. There were no cases of intraventricular or subgaleal hemorrhage on clinical or ultrasound examination, but one stillborn infant, who succumbed to a generalized coagulation defect, had a subarachnoid hemorrhage. Finally, there was no significant difference in Sarnat encephalopathy staging or Scanlon neurobehavioral assessment between spontaneous vaginal, forceps, and vacuum extractor deliveries.(ABSTRACT TRUNCATED AT 250 WORDS)     

Differences between obstetricians in caesarean section rates and the management of labour.

OBJECTIVE: To determine if interobstetrician variation in caesarean section rates was associated with different approaches to the management of labour. DESIGN: A retrospective cohort study. SETTING: A tertiary care teaching hospital in Quebec, Canada. SUBJECTS: 546 nulliparae in spontaneous labour at term were grouped according to the rate of caesarean sections for dystocia of their obstetrician (high: women of two obstetricians with rates of 13.2% and 15.0%; and low: women of three obstetricians with rates of 6.0%, 6.2% and 6.5%). MAIN OUTCOME MEASURES: Frequency and timing of oxytocin, epidural, amniotomy, forceps. SECONDARY OUTCOME MEASURES: Indicators of neonatal asphyxia and trauma. RESULTS: No difference between groups was observed in the frequency or timing of use of oxytocin or epidural analgesia. Amniotomy was practised earlier by the obstetricians in the high group. Differences in section rates for dystocia were greatest in the second stage (low-2.4%, high-7.9%). Obstetricians in the low group intervened earlier with forceps or vacuum extractor. Nine babies (all in the low group), 8 of whom had had an instrumental vaginal delivery, suffered trauma (5 clavicular fractures, 4 facial palsies) (Fisher's exact test, P = 0.0139). CONCLUSION: The practice patterns of the two groups are distinguished by differences in management of the second stage. Although lower section rates were associated with an increase in mild neonatal trauma, this appears to have been mediated by the earlier use of forceps in this group.     

Cord blood acid-base status in neonates delivered by Silastic vacuum cup extraction: comparison with forceps and spontaneous deliveries

Umbilical cord blood gases were measured as objective parameters of neonatal outcome in patients delivered by Silastic vacuum extractor and were compared with those values from patients delivered spontaneously, by forceps, or by sequential use of vacuum and forceps. The results demonstrated no clinically significant differences among the groups in cord blood pH, pCO2, pO2, base excess, or bicarbonate values. These observations provide reassurance that the Silastic vacuum extractor is a safe alternative for vaginal delivery of the appropriately selected term fetus.     

Is the Vacuum Extractor Really the Instrument of First Choice?

This study was a retrospective analysis of the pattern of usage of both the forceps and vacuum extractor as well as the neonatal outcome on all the instrumental deliveries conducted in 1995 at the Kandang Kerbau Hospital, Singapore. There were a total of 927 forceps deliveries and 495 vacuum extractions but neonatal data was available for only 481 forceps and 255 vacuum extractor babies. (There were 2 neonatal units which accepted admissions on alternate days; all of the data were collected from 1 of the units only). Demographic data were comparable in most aspects except that vacuum deliveries were significantly associated with higher parity and shorter labours. There was a trend towards using the vacuum extractor in less difficult cases. Almost all the instrumental deliveries were conducted by specialists. Birth trauma was significantly more likely to occur with the vacuum extractor. Almost all the deliveries were conducted with similar expertise in both groups, yet the use of the vacuum extractor resulted in more birth trauma even in the presence of 'easier' cases. This may suggest an inherent risk in using the vacuum extractor.     

Cohort study of Silastic obstetric vacuum cup deliveries: II. Unsuccessful vacuum extraction

In a cohort analysis of Silastic vacuum extractor deliveries, 65% were completed with the vacuum extractor alone, 24% with outlet forceps, 3% with midforceps, and 7% with cesarean section (vacuum extractor-cesarean). Control groups were formed by using the next sequential forceps delivery, spontaneous vaginal delivery, and every second cesarean section after a trial of labor. The infants were examined using a neurobehavioral scale, an encephalopathy assessment, cranial ultrasound, and indirect ophthalmoscopy. In the combined vacuum extractor and forceps delivery subgroup (vacuum extractor-forceps), all but 3% were converted from a high mid-forceps delivery to outlet forceps by the initial vacuum extractor procedure, thus eliminating many difficult midforceps deliveries. The study yielded no significant difference in maternal morbidity between vacuum extractor-forceps and forceps delivery, no difference in vaginal trauma for vacuum extractor-cesarean versus vacuum extractor delivery, and no greater hospital stay, infection rate, or need for transfusion for either vacuum extractor-forceps versus forceps delivery or vacuum extractor-cesarean versus cesarean delivery. Neonatal morbidity did not differ between successful and unsuccessful trial of vacuum extractor, except for an increased frequency of retinal hemorrhage. The frequency of scalp trauma, including cephalohematoma, did not differ between vacuum extractor-forceps and forceps delivery, or between vacuum extractor-cesarean and vacuum extractor delivery. For vacuum extractor-forceps versus forceps delivery and vacuum extractor-cesarean versus cesarean section, there were no significant differences in neurobehavioral or encephalopathy scores, or in the frequency of neonatal jaundice, facial palsy, anemia, fractures, or mortality.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of sequential use of vacuum and forceps for assisted vaginal delivery on neonatal and maternal outcomes

OBJECTIVE: To determine the risk of neonatal and maternal disease associated with the sequential use of vacuum and forceps compared with spontaneous vaginal delivery. STUDY DESIGN: Using Washington state birth certificate data linked to hospital discharge records, we compared 3741 vaginal deliveries by both vacuum and forceps, 3741 vacuum deliveries, and 3741 forceps deliveries to 11,223 spontaneous vaginal deliveries. RESULTS: Compared with spontaneous vaginal deliveries, deliveries by sequential use of vacuum and forceps had significantly higher rates of intracranial hemorrhage (relative risk [RR], 3.9; 95% confidence interval [CI], 1.5 to 10.1), brachial plexus (RR, 3.2; 95% CI, 1.6 to 6.4), facial nerve injury (RR, 13.3; 95% CI, 4.7 to 37.7), seizure (RR, 13.7; 95% CI, 2.1 to 88.0), depressed 5-minute Apgar score (RR, 3.0; 95% CI, 2.2 to 4.0), assisted ventilation (RR, 4.8; 95% CI, 2.1 to 11.0), fourth-degree (RR, 11.4; 95% CI, 6.4 to 20.1 among multiparous women) and other lacerations, hematoma (RR, 6.2; 95% CI, 2.1 to 18.1 among multiparous women), and postpartum hemorrhage (RR, 1.6; 95% CI, 1.3 to 2.0). The relative risk of sequential vacuum and forceps use was greater than the sum of the individual relative risks of each instrument for intracranial hemorrhage, facial nerve injury, seizure, hematoma, and perineal and vaginal lacerations. CONCLUSION: Sequential use of vacuum and forceps is associated with increased risk of both neonatal and maternal injury.     

Instrumental delivery: clinical practice guidelines from the French College of Gynaecologists and Obstetricians

Routine use of a partograph is associated with a reduction in the use of forceps, but is not associated with a reduction in the use of vacuum extraction (Level A). Early artificial rupture of the membranes, associated with oxytocin perfusion, does not reduce the number of operative vaginal deliveries (Level A), but does increase the rate of fetal heart rate abnormalities (Level B). Early correction of lack of progress in dilatation by oxytocin perfusion can reduce the number of operative vaginal deliveries (Level B). The use of low-concentration epidural infusions of bupivacaine potentiated by morphinomimetics reduces the number of operative interventions compared with larger doses (Level A). Placement of an epidural before 3-cm dilatation does not increase the number of operative vaginal deliveries (Level A).Posterior positions of the fetus result in more operative vaginal deliveries (Level B). Manual rotation of the fetus from a posterior position to an anterior position may reduce the number of operative deliveries (Level C). Walking during labour is not associated with a reduction in the number of operative vaginal deliveries (Level A). Continuous support of the parturient by a midwife or partner/family member during labour reduces the number of operative vaginal deliveries (Level A). Under epidural analgesia, delayed pushing (2 h after full dilatation) reduces the number of difficult operative vaginal deliveries (Level A). Ultrasound is recommended if there is any clinical doubt about the presentation of the fetus (Level B).The available scientific data are insufficient to contra-indicate attempted midoperative delivery (professional consensus). The duration of the operative intervention is slightly shorter with forceps than with a vacuum extractor (Level C). Nonetheless, the urgency of operative delivery is not a reason to choose one instrument over another (professional consensus). The cup-shaped vacuum extractor seems to be the instrument of choice for operative deliveries of fetuses in a cephalic transverse position, and may also be preferred for fetuses in a posterior position (professional consensus). Vacuum extraction deliveries fail more often than forceps deliveries (Level B).Overall, immediate maternal complications are more common for forceps deliveries than vacuum extraction deliveries (Level B). Compared with forceps, operative vaginal delivery using a vacuum extractor appears to reduce the number of episiotomies (Level B), first- and second-degree perineal lesions, and damage to the anal sphincter (Level B). Among the long-term complications, the rate of urinary incontinence is similar following forceps, vacuum extraction and spontaneous vaginal deliveries (Level B). Anal incontinence is more common following forceps delivery (Level B). Persistent anal incontinence has a similar prevalence regardless of the mode of delivery (caesarean or vaginal, instrumental or non-instrumental), suggesting the involvement of other factors (Level B). Rates of immediate neonatal mortality and morbidity are similar for forceps and vacuum extraction deliveries (Level B). It appears that difficult instrumental delivery may lead to psychological sequelae that may result in a decision not to have more children (Level C). The rates of neonatal convulsions, intracranial haemorrhage and jaundice do not differ between forceps and vacuum extraction deliveries (Levels B and C).Rapid sequence induction with a Sellick manoeuvre (pressure to the cricoid cartilage) and tracheal intubation with a balloon catheter is recommended for any general anaesthesia (Level B).Training must ensure that obstetricians can identify indications and contra-indications, choose the appropriate instrument, use the instruments correctly, and know the principles of quality control applied to operative vaginal delivery. Nowadays, traditional training can be accompanied by simulations. Training should be individualized and extended for some students.     

Neonatal Outcome Following Failed Kiwi OmniCup Vacuum Extraction

ObjectiveTo evaluate neonatal outcomes following failed vacuum extraction using the Kiwi OmniCup vacuum device.MethodsWe conducted a retrospective study of 288 failed vacuum deliveries using the OmniCup device. The neonatal morbidity was recorded for each delivery.ResultsOf the 288 women involved, 82.3% were nulliparous. In 245 cases (85.1%), failed vacuum was followed by successful forceps delivery; failed vacuum and failed forceps was followed by Caesarean section in 5.9%; failed vacuum was followed by spontaneous vaginal delivery in 3.8%; and failed vacuum was followed by Caesarean section in 5.2%. Cephalhematoma was diagnosed in 19.8% of the 288 infants delivered. There were no cases of neonatal intracranial or subgaleal hemorrhage.ConclusionAlthough the method of delivery following failed vacuum extraction is controversial, and most national guidelines warn of increased neonatal morbidity with subsequent use of forceps, the low morbidity in this study is reassuring. In our cohort, low forceps delivery (station >2 cm) following failed vacuum extraction was not associated with serious neonatal morbidity.     

Instrumental extraction in 2002 in the "AURORE" hospital network: incidence and serious neonatal complications

OBJECTIVES: The purpose of this study was to evaluate the incidence of forceps and vacuum application and the incidence of its related neonatal complications. This study was performed in a network of 37 maternity hospitals. PATIENTS AND METHOD: A postal questionnaire was sent to 156 obstetricians between February and March 2003. RESULTS: Response rate was 78%. In 2002 the operative vaginal delivery rate was 11.2% of all live births. Forceps are the primary instruments (6.3%) whereas vacuum delivery rate was 4.9%. One obstetrician never uses forceps while 38 (31%) never use vacuum. Only 29 (24%) report using both instruments frequently. During 2002 no neonatal death related to an operative vaginal delivery was reported while 145 neonatal complications were (3.2%). Major complications were one depressed skull fracture (1/4589) and 14 extensive caput succedaneum (14/4589). Minor complications were cutaneous lesions (124/4589) and facial palsy (6/4589). Vacuum delivery was associated with a significantly higher extensive caput succedaneum rate (P = 0.018) while the only depressed skull fracture observed was related to forceps use. Forceps delivery was associated with a significantly higher cutaneous lesions rate (P < 0.001). DISCUSSION AND CONCLUSIONS: This study showed that, in 2002, operative vaginal deliveries still represent a significant amount of vaginal deliveries, a majority of obstetricians do not use both instrument and neonatal associated complications are frequent (3.2%) but rarely severe. Therefore, we believe that every method that allows a safe teaching of operative delivery should be promoted.     

Maternal and child health after assisted vaginal delivery: five-year follow up of a randomised controlled study comparing forceps and ventouse.

OBJECTIVE: To undertake a five year follow up of a cohort of women and children delivered by forceps or vacuum extractor in a randomised controlled study. DESIGN: Follow up of a randomised controlled trial. SETTING: District general hospital in the West Midlands. POPULATION: Follow up questionnaires were sent to 306 of the 313 women originally recruited at the North Staffordshire Hospital to a randomised controlled study comparing forceps and vacuum extractor for assisted delivery. Two hundred and twenty-eight women responded (74.5%) and all were included in the study; forceps (n = 115) and vacuum extractor (n = 113). MAIN OUTCOME MEASURES: Bowel and urinary dysfunction, child vision assessment, and child development. RESULTS: Maternal adverse symptoms at long term follow up were relatively common. Urinary incontinence of various severity was reported by 47%, bowel habit urgency was reported by 44% (98/225), and loss of bowel control 'sometimes' or 'frequently' by 20% of women (46/226). No significant differences between instruments were found in terms of either bowel or urinary dysfunction. Overall, 13% (20/158) of children were noted to have visual problems. There was no significant difference in visual function between the two groups: ventouse 11/86 (12.8%), compared with forceps 9/72 (12.5%); odds ratio 0.97, 95% CI 0.38-2.50. Of the 20 children with visual problems, a family history was known in 18, and 17/18 (94%) had a positive family history for visual problems. No significant differences in child development were found between the two groups. CONCLUSIONS: There is no evidence to suggest that at five years after delivery use of the ventouse or forceps has specific maternal or child benefits or side effects.     

Risk of new-onset urinary incontinence after forceps and vacuum delivery in primiparous women

OBJECTIVE: We sought to determine the incidence of new-onset urinary incontinence after forceps and vacuum delivery compared with spontaneous vaginal delivery. STUDY DESIGN: We performed a prospective study in primiparous women delivered by forceps (n = 90), vacuum (n = 75), or spontaneous vaginal delivery (n = 150). Follow-up for urinary incontinence was at 2 weeks, 3 months, and 1 year after delivery. RESULTS: The incidence of urinary incontinence was similar in the 3 groups at 2 weeks after delivery. The proportion of women developing new-onset urinary incontinence decreased significantly over time in the spontaneous vaginal (P =.003) and vacuum delivery groups (P =.009) but not in the forceps group (P =.2). No relationship of urinary incontinence with vaginal lacerations, epidural anesthesia, length of second stage of labor, or infant birth weight was seen. CONCLUSIONS: In primiparous women, urinary incontinence after forceps delivery is more likely to persist compared with spontaneous vaginal or vacuum delivery.     

中心电子监护系统的临床应用

目的 探讨使用中心电子监护系统对提高产科质量的作用。方法 对１９７９年１１月 １９９８年３月在我院分娩的孕周≥３７周的１２１６例孕妇进行ＣＥＭＳ监护,并与１９９６年１１月至１９９７年３月在我院分娩的孕周≥３７周、未行ＣＥＭＳ监护的１１３７例孕妇（对照组）进行比较,分析两组胎儿窘迫发生率,新生儿窒息发生率,剖宫痃和阴道手术率。结果 姐与则组胎儿窘迫发生率分别为９．８％、１２．８％;新生窒息发生率分别     

Failed individual and sequential instrumental vaginal delivery: contributing risk factors and maternal-neonatal complications

BACKGROUND: To identify the risk factors for failed instrumental vaginal delivery, and to compare maternal and neonatal morbidity associated with failed individual and sequential instruments used. DESIGN: A retrospective case-control study. METHODS: From January 1995 to June 2001, there were 39 508 live births at >37 weeks' gestation of which 2628 (6.7%) instrumental vaginal deliveries were performed, 1723 (4.4%) were vacuum extractions and 905 (2.3%) were forceps. A total of 155/2628 (5.9%) patients who had failed instrumental delivery were matched with 204 patients who had successful instrumental delivery. The patients were divided into five groups. Group I (n = 129) had failed vacuum extraction, group II (n = 13) failed forceps, group III (n = 13) failed both (i.e. failed attempt at both instruments sequentially), group IV (n = 138) had successful vacuum extraction and group V (n = 66) successful forceps. RESULTS: The failure rate for vacuum extractions 129/1723 (7.5%) was significantly higher than that for forceps 13/905 (1.4%) [odds ratio (OR) = 5.6, 95% CI 3-10.3]. There were no significant differences in all maternal complications (25.5% vs. 26.6%) between vacuum (groups I and IV) and forceps (groups II and V) assisted deliveries. There were more maternal complications in group III (46.2%) than in groups I (35.7%), II (23.1%) and V (27.3%) that did not reach statistical significance but were significantly higher than in group IV (15.9%, OR = 4.5, 95% CI 1.2-16.9). There was a significantly higher rate of all fetal complications in group III [11/13 (84.6%)] than in groups I [69/129 (53.5%)], II [7/13 (53.8%)], IV [35/138 (25.4%)] and V [22/66 (33.3%)] (OR = 4.8, 95% CI 0.9-19.9). CONCLUSIONS: Applying the instrument at < or =0 fetal station, nulliparous women, history of previous cesarean section and fetal head other than occipitoanterior position were risk factors for failed instrumental delivery. Sequential use of instrumental delivery carries a significantly higher neonatal morbidity than when a single instrument is used.     

Influence of introducing a maneuverable vacuum extractor cup on maternal hospital stay after instrumental birth. Retrospective cohort study

ObjectivesThe aim of our study is to evaluate the impact of the introduction of a maneuverable vacuum extractor cup on the length of hospital stay after assisted vaginal birth in nulliparous women in a hospital where no vacuum devices were used.MethodsThis single center retrospective analytical study included two groups of nulliparous women who had undergone an assisted vaginal birth. The 2 groups differ according to the availability or not of a maneuverable vacuum extractor cup. The first group includes the last 54 instrumental births until May 2017, when only obstetric forceps and Thierry's spatulas were available in our center; the second group includes the first 54 instrumental births since May 2018 in our center, when obstetric forceps, Thierry's spatulas and maneuverable vacuum extractor cup were available. Maneuverable vacuum extractor cups had been available for 12 months in the second group.ResultsIn the no vacuum cup group, Kjelland forceps and Thierry's spatulas were used in 29 (53.7%) and 25 (46.3%) of the 54 assisted vaginal births, respectively. In the vacuum available group, a vacuum cup was chosen in 30 (55.6%), Kjelland forceps were used in 18 (33.3%) and Thierry's spatulas in 6 (11.1%) of the assisted vaginal births. 22 women (40.7%) had a postpartum hospital stay longer than 3 days in the group with no maneuverable vacuum extractor cup availability, versus 3 women (5.6%) in the group with availability of a maneuverable vacuum extractor cup, p < 0.001. Average postpartum hospital stay length was 3.17 ± 0.803 days versus 2.81 ± 0.585, p < 0.001. There was also a significant reduction in the number of episiotomies.ConclusionThe introduction of a maneuverable vacuum extractor cup in a center where only forceps and Thierry's spatulas had been used resulted in a decrease in postpartum hospital stay in nulliparous women.     

Maternal and child health after assisted vaginal delivery: five-year follow up of a randomised controlled study comparing forceps and ventouse

Objective To undertake a five year follow up of a cohort of women and children delivered by forceps or vacuum extractor in a randomised controlled study.
Design Follow up of a randomised controlled trial.
Setting District general hospital in the West Midlands.
Population Follow up questionnaires were sent to 306 of the 313 women originally recruited at the North Staffordshire Hospital to a randomised controlled study comparing forceps and vacuum extractor for assisted delivery. Two hundred and twenty-eight women responded (74.5%) and all were included in the study; forceps (   n = 115  ) and vacuum extractor (   n = 113  ).
Main outcome measures Bowel and urinary dysfunction, child vision assessment, and child development.
Results Maternal adverse symptoms at long term follow up were relatively common. Urinary incontinence of various severity was reported by 47%, bowel habit urgency was reported by 44% (98/225), and loss of bowel control 'sometimes' or 'frequently' by 20% of women (46/226). No significant differences between instruments were found in terms of either bowel or urinary dysfunction. Overall, 13% (20/158) of children were noted to have visual problems. There was no significant difference in visual function between the two groups: ventouse 11/86 (12.8%), compared with forceps 9/72 (12.5%); odds ratio 0.97,95% CI 0.38–2.50. Of the 20 children with visual problems, a family history was known in 18, and 17/18 (94%) had a positive family history for visual problems. No significant differences in child development were found between the two groups.
Conclusions There is no evidence to suggest that at five years after delivery use of the ventouse or forceps has specific maternal or child benefits or side effects.     

Choosing between bad,worse and worst: what is the preferred mode of delivery for failure of the second stage of labor?*

Objective: To determine the preferred mode of delivery (vacuum, forceps or cesarean delivery) for second-stage dystocia.

Methods: Retrospective cohort study of women delivered by forceps, vacuum or cesarean delivery due to abnormalities of the second stage of labor. Primary outcome included neonatal and maternal composite adverse effects.

Results: A total of 547 women were included: 150 (27.4%) had forceps delivery, 200 (36.5%) had vacuum extraction, and 197 (36.1%) had cesarean section. The rate of neonatal composite outcome was significantly increased in vacuum extraction (27%) compared to forceps delivery (14.7%) or cesarean section (9.7%) (p?p?=?0.004).

Conclusion: Operative vaginal delivery was associated with reduced postpartum infection compared to cesarean section. Forceps delivery was associated with reduced risk for adverse neonatal outcome compared to vacuum extraction, with no increase in the risk of composite maternal complications.     

Sequential use of instruments at operative vaginal delivery: Is it safe?

Objective: Our purpose was to examine maternal and neonatal outcomes in a cohort of women who underwent delivery with the sequential use of instruments. Study Design: This retrospective case-control study included deliveries from May 1996 through March 1998. Charts of women who underwent delivery with the sequential use of instruments (vacuum first, then forceps, or vice versa) were identified. Two control groups (1 forceps group, 1 vacuum group) were randomly selected and matched for each case. Maternal and neonatal outcomes were abstracted and compared. Results: There were 34 patients in each group. There were no significant demographic differences. The vacuum group had lower rates of episiotomy (P = .01) and deep perineal lacerations (P = .014), whereas these outcomes were similar in the sequential and forceps groups. All other maternal outcomes were equivalent. There were no differences in any neonatal parameter except for superficial scalp trauma, which was more common in the vacuum group (P = .002). Conclusion: We conclude that the prudent use of sequential instruments at operative vaginal delivery did not engender higher rates of maternal or neonatal morbidity. (Am J Obstet Gynecol 1999;180:1446-9.)     

Comparison of maternal and neonatal morbidity in midforceps delivery and midpelvis vacuum extraction

The present study examines the incidence of maternal and neonatal morbidity associated with delivery from the midpelvis using the vacuum extractor when compared with obstetric forceps. Previous studies have failed to minimize the influence of confounding variables such as maternal and neonatal disease and indication for delivery on outcome when comparing determinants of maternal and neonatal morbidity in the two groups. Results indicate that there was significantly more maternal morbidity in forceps deliveries across most variables. There were no statistically significant differences in neonatal morbidity between the two groups except for a higher incidence of inconsequential cephalhematoma in the vacuum group. It is concluded that the vacuum extractor may be a valuable instrument in delivery from the midpelvis and that it should be more widely used in appropriate clinical situations.     

Clinical assessment of the Kobayashi vacuum extractor

Four hundred and thirty-one vacuum extraction deliveries were reviewed during a five-year period from 1978 to 1983. All cases involved the use of the Kobayashi silastic cup vacuum extractor with nine participating obstetricians performing the procedures. Specific attention was directed toward maternal and fetal morbidity associated with the use of the silastic cup extractor. No maternal or fetal deaths occurred. Vaginal and cervical lacerations accounted for a 4% maternal morbidity rate. Seventy-five percent of the infants had Apgar scores greater than 7 at one minute, and 97% had scores greater than 7 at five minutes. Fetal morbidity was impressively low, with a cephalohematoma rate of 6% and only two instances of major fetal cranial hemorrhages. In comparison with the reported morbidity sited by other authors using the metal cup extractor, less fetal scalp trauma may be anticipated with the judicious use of the Kobayashi silastic cup vacuum extractor.     

Cohort study of maternal and neonatal morbidity in relation to use of episiotomy at instrumental vaginal delivery

OBJECTIVE: The aim of this study was to investigate the maternal and neonatal morbidity related to use of episiotomy for vacuum and forceps deliveries. DESIGN: Retrospective population-based cohort study. SETTING: Dundee, Scotland. POPULATION: Two thousand one hundred and fifty three women who experienced an instrumental vaginal delivery between January 1998 and December 2002. METHODS: Univariate and multivariate logistic regression analyses were performed comparing deliveries with and without the use of episiotomy. MAIN OUTCOME MEASURES: Extensive perineal tears (third and fourth degree) and shoulder dystocia. RESULTS: Two hundred and forty-one (11%) of the 2153 women who underwent instrumental vaginal deliveries did not receive an episiotomy. Vacuum delivery was associated with less use of episiotomy compared with forceps (odds ratio 0.10, 95% CI 0.07-0.14). Extensive perineal tears were more likely with use of episiotomy (7.5%vs 2.5%, adjusted OR 2.92, 95% CI 1.27-6.72) as was neonatal trauma (6.0%vs 1.7%, adjusted OR 2.62, 95% CI 1.05-6.54). Use of episiotomy did not reduce the risk of shoulder dystocia (6.9%vs 4.6%, adjusted OR 1.43, 95% CI 0.74-2.76). The findings were similar for delivery by vacuum and forceps. CONCLUSION: The use of episiotomy increased the risk of extensive perineal tears without a reduction in the risk of shoulder dystocia.