Obstetric vacuum extraction: state of the art in the new millennium

Neonatal Birth Trauma: Analysis of Yearly Trends, Risk Factors, and Outcomes

OBJECTIVE

To evaluate the trends, proportions, risk factors, resource utilization, and outcomes of neonatal birth trauma in the US.

STUDY DESIGN

This cross-sectional study of in-hospital births used the Nationwide Inpatient Sample for 2006-2014. We divided the cases by type of birth trauma: scalp injuries and major birth trauma. Linear regression for yearly trends and logistic regression were used for risk factors and outcomes. A generalized linear model was used, with a Poisson distribution for the length of stay and a gamma distribution for total spending charges.

RESULTS

A total of 982 033 weighted records with neonatal birth trauma were found. The prevalence rate increased by 23% from (from 25.3 to 31.1 per 1000 hospital births). Scalp injuries composed 80% of all birth traumas and increased yearly from 19.87 to 26.46 per 1000 hospital births. Major birth trauma decreased from 5.44 to 4.67 per 1000 hospital births due to decreased clavicular fractures, brachial plexus injuries, and intracranial hemorrhage. There were significant differences in demographics and risk factors between the 2 groups. Compared with scalp injuries, major birth trauma was associated with higher odds of hypoxic-ischemic encephalopathy, seizures, need for mechanical ventilation, meconium aspiration, and sepsis. Length of stay was increased by 56%, and total charges were almost doubled for major birth trauma.

CONCLUSIONS

Neonatal birth trauma increased over the study period secondary to scalp injuries. Major birth trauma constitutes a significant health burden. Scalp injuries are also associated with increased morbidity and might be markers of brain injury in some cases.

Association between the number of pulls and adverse neonatal/maternal outcomes in vacuum-assisted delivery

OBJECTIVES

To determine the association between the number of pulls during vacuum-assisted deliver and neonatal and maternal complications.

METHODS

This was a single-center observational study using a cohort of pregnancies who underwent vacuum-assisted delivery from 2013 to 2020. We excluded pregnancies transitioning to cesarean section after a failed attempt at vacuum-assisted delivery. The number of pulls to deliver the neonate was categorized into 1, 2, 3, and ≥4 pulls. We used logistic regression models to investigate the association between the number of pulls and neonatal intensive care unit (NICU) admission and maternal composite outcome (severe perineal laceration, cervical laceration, transfusion, and postpartum hemorrhage ≥500 mL).

RESULTS

We extracted 480 vacuum-assisted deliveries among 7,321 vaginal deliveries. The proportion of pregnancies receiving 1, 2, 3, or ≥4 pulls were 51.9, 28.3, 10.8, and 9.0%, respectively. The crude prevalence of NICU admission with 1, 2, 3, and ≥4 pulls were 10.8, 16.2, 15.4, and 27.9%, respectively. The prevalence of NICU admission, amount of postpartum hemorrhage, and postpartum hemorrhage ≥500 mL were significantly different between the four groups. Multivariable logistic regression analysis found the prevalence of NICU admission in the ≥4 pulls group was significantly higher compared with the 1 pull group (adjusted odds ratio, 3.3; 95% confidence interval, 1.4-7.8). In contrast, maternal complications were not significantly associated with the number of pulls.

CONCLUSIONS

Vacuum-assisted delivery with four or more pulls was significantly associated with an increased risk of NICU admission. However, the number of pulls was not associated with maternal complications.

Safety of uterine fundal pressure maneuver during second stage of labor in a tertiary perinatal medical center: A retrospective observational study

OBJECTIVE

This study aimed to evaluate the conformity of the indications and implementation status of uterine fundal pressure maneuver (UPFM) and to examine its safety according to the Japan Society of Obstetrics and Gynecology (JSOG) guidelines.

MATERIALS AND METHODS

We selected all the patients (n = 265) who were treated with UFPM between January 2015 and March 2017. We first evaluated the conformity of the indications and implementation status of UFPM concerning the guidelines for obstetrical practice in Japan, 2017. Second, we retrospectively examined maternal and fetal adverse events (AEs) to determine the safety of UFPM.

RESULTS

In total, 265 patients underwent UFPM; of all the UFPM-assisted deliveries, 189 patients (72%) were evaluated for conformity. Of these 189 patients, 181 (95.7%) were confirmed to be compliant. Laceration of the birth canal was the most frequently occurring maternal AE, followed by cervical laceration. No cases of uterine rupture, severe AEs leading to an extended hospital stay, and maternal deaths were observed. Although fetal AEs requiring admission to neonatal intensive care unit (NICU) were recorded for 33 patients (12.5%), all newborns developed normally without sequela.

CONCLUSION

The findings of this study may support the validity of the 2017 guidelines. Because it is difficult to find evidence of the safety of use of UFPM, it is essential to accumulate experiences and results learned in clinical practice to build a consensus in the future using the current 2017 guidelines as a standard as done in the current study.

Adverse neonatal and maternal outcome following vacuum-assisted vaginal delivery: does indication matter?

PURPOSE

To estimate the impact of indication for vacuum-assisted vaginal delivery on neonatal and maternal adverse outcome.

METHODS

Retrospective analysis of women carrying singleton-term pregnancies undergoing vacuum-assisted vaginal delivery in a tertiary hospital (2007-2014). Cohort was stratified by indication: non-reassuring fetal heart rate or prolonged second stage. Primary outcome was adverse neonatal outcome and secondary outcome was maternal morbidity. Logistic regression analysis was utilized to adjust for potential confounders.

RESULT

Overall, 4931 women met inclusion criteria. Delivery indication was prolonged second stage in 3143 (64%) cases and non-reassuring fetal heart rate in 1788 (36%). In the non-reassuring fetal heart rate group, there were higher rates of cephalohematoma, low 5-min Apgar-score, and asphyxia. In the prolonged second-stage group, there were higher rates of sepsis and post-partum hemorrhage. Composite neonatal birth trauma and maternal morbidity were higher for vacuum-assisted vaginal delivery following prolonged second stage. Following adjustment for confounders cephalohematoma (aOR 1.21, 95% CI 1.04-1.41), low 5-min Apgar-score (aOR 2.91, 95% CI 1.26-4.67) and asphyxia (aOR 1.81 95% CI 1.35-2.44) remained significant in the non-reassuring fetal heart rate group and neonatal sepsis remained significant for the prolonged second-stage group (aOR 1.77, 95% CI 1.38-2.27), p < 0.05 for all. However, there was no longer difference in the composite birth trauma, other neonatal or maternal morbidity.

CONCLUSION

The indication for vacuum-assisted vaginal delivery has an impact on neonatal outcome. While cephalohematoma, low 5' Apgar score, and asphyxia were more common in the non-reassuring fetal heart rate group, neonatal sepsis was more common in cases of prolonged second stage of labor.

Obstetric management in vacuum-extraction deliveries

OBJECTIVE

The 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.

METHODS

In 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.

RESULTS

In 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.

CONCLUSION

The 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.

Early Blood Transfusion and Resolution of Disseminated Intravascular Coagulation Associated with Massive Subgaleal Hemorrhage

A male infant delivered to a primipara woman following vacuum applications. He was vigorous at birth, with small caput and scalp bruising. His head was enlarging; he became pale with respiratory distress. Subgaleal hemorrhage (SGH) was suspected. His hematocrit was noted to be 26.2 percent prior to transfusion of O, Rh-negative blood (40 mL/kg). Moderate disseminated intravascular coagulation (DIC) was noted at 12 hours of age. Posttransfusion of fresh frozen plasma (FFP), his condition became stable, and DIC gradually resolved. Head magnetic resonance imaging did not show intracranial hemorrhage. Although one episode of seizures was noted, electroencephalogram was normal. With the application of obstetric vacuum, we recommend that the neonatal health care professionals frequently evaluate the infant's condition. In light of developing fluctuant subgaleal fluid associated with pallor, anemia, metabolic acidosis, and respiratory distress, immediate blood transfusion is warranted. In the presence of DIC, transfusion of FFP is beneficial.

Prediction of neonatal outcome in women with gestational hypertension or mild preeclampsia after 36 weeks of gestation

BACKGROUND

There is little knowledge about neonatal complications in GH and PE and induction at term, we aim to assess whether they can be predicted from clinical data.

METHODS

We used data of the HYPITAT trial and evaluated whether adverse neonatal outcome (Apgar score < 7, pH < 7.05, NICU admission) could be predicted from clinical data. Logistic regression, ROC analysis and calibration were used to identify predictors and evaluate the predictive capacity in an antepartum and intrapartum model.

RESULTS

We included 1153 pregnancies, of whom 76 (6.6%) had adverse neonatal outcome. Parity (primipara OR 2.75), BMI (OR 1.06), proteinuria (dipstick +++ OR 2.5), uric acid (OR 1.4) and creatinine (OR 1.02) were independent antepartum predictors; In the intrapartum model, meconium stained amniotic fluid (OR 2.2), temperature (OR 1.8), duration of first stage of labour (OR 1.15), proteinuria (dipstick +++ OR 2.7), creatinine (OR 1.02) and uric acid (OR 1.5) were predictors of adverse neonatal outcome. Both models showed good discrimination (AUC 0.75 and 0.78), but calibration was limited (Hosmer-Lemeshow p = 0.41, and p = 0.20).

CONCLUSIONS

In women with GH or PE at term, it is difficult to predict neonatal complications, possibly since they are rare in the term pregnancy. However, the identified individual predictors may guide physicians to anticipate requirements for neonatal care.

Selective uterine fundal pressure maneuver during the second stage of the first twin delivery at near term

OBJECTIVE

We examined the perinatal outcomes of twin deliveries following selective uterine fundal pressure maneuver (UFPM) during the second stage of the first twin delivery.

METHODS

At our institute, if non-reassuring fetal heart rate and/or maternal exhaustion were observed during the second stage of the first twin, selective UFPM was performed following making sure of the position of the first twin's buttocks by ultrasonography. We reviewed the obstetric records of all cases of trial of vaginal delivery of twins between 2002 and 2012.

RESULTS

A total of 64 cases were evaluated for the statistical analyses. Of these, selective UFPM for the first twin was performed in 15 cases (24%). Although the cases requiring selective UFPM for the first twin was associated with an increased postpartum hemorrhage, there were no significant differences in neonatal outcomes between the two groups.

CONCLUSION

There was no evidence that the selective UFPM is unsafe for both mother and two babies during the second stage of the first twin delivery.

Birth by vacuum extraction delivery and school performance at 16 years of age

OBJECTIVE

The aim of the present study was to investigate cognitive competence, as indicated by school performance, at 16 years of age, in children delivered by vacuum extraction.

STUDY DESIGN

This was a register study of a national cohort of 126,032 16 year olds born as singletons, with a vertex presentation, at a gestational age of 34 weeks or older, with Swedish-born parents, delivered between 1990 and 1993 without major congenital malformations. Linear regression was used to analyze mode of delivery in relation to mean scores from national tests in mathematics (40.2; scale, 10-75; SD, 14.9) and mean average grades (223.8; scale, 10-320; SD, 52.3), with adjustment for perinatal and sociodemographic confounders.

RESULTS

Children delivered by vacuum extraction (-0.51; 95% confidence interval [CI], -0.76 to 0.26) as well as by nonplanned cesarean section (-0.51; 95% CI, -0.82 to -0.20) had slightly lower mean mathematics test scores than children born vaginally without instruments, after adjustment for major confounders. Mean average grades in children delivered by vacuum extraction were -1.05 (95% CI, -1.87 to -0.23) and -1.20 (95% CI,-2.24 to -0.16) in children delivered by nonplanned cesarean section compared with children born vaginally.

CONCLUSION

Children delivered by vacuum extraction had slightly lower grades at age 16 years compared with those born by noninstrumental vaginal delivery but very similar to those delivered by nonplanned cesarean. This suggests that vacuum extraction and nonplanned cesarean are equivalent alternatives for terminating deliveries with respect to cognitive outcomes.

[Failure of vacuum extractions: risk factors, maternal and fetal issues]

OBJECTIVES

Determine cases which are at risk of vacuum extraction failure as well as maternal and foetal issues depending on the delivery outcome.

MATERIAL AND METHODS

It was a retrospective study comparing 147 vacuum failures, from January 2002 to December 2010, with a control group randomly composed of 526 successful vacuum extractions. The outcomes were high risk situations of vacuum failure, maternal and neonatal morbidity depending on the delivery method (caesarean section or other instrumental extraction).

RESULTS

The global vacuum failure rate was 3.3 %. During labour, we identified several situations at risk of vacuum extraction failure: cephalhematomas prior to extraction (P<0.001), deflexion attitude (P<0.001), posterior variety (P<0.001), entering above the inlet strait (P<0.001), occiput posterior delivery (P<0.001), fœtal weight greater than 3500g (P=0.023). Neonatals consequency were more Apgar score below 7 at five minutes life (P=0.007), fœtal acidosis (pH<7,20) (P=0.032), neonatal resuscitation (P<0.001), and craniofacial damages (P<0.001).

CONCLUSION

Many dystocic situations occurring during labour require intense care when practicing vacuum extraction since they more frequently result in failure. In case of vacuum extraction failure, immediate adaptation to extra-uterine life seems to be more difficult for new-born babies.

Birth trauma--risk factors and short-term neonatal outcome

OBJECTIVE

The ability to predict birth trauma (BT) based on the currently recognized risk factors is limited and there is little information regarding the short-term neonatal outcome following BT. We aimed to identify risk factors for BT and to evaluate the effect of BT on short-term neonatal outcome.

METHODS

A retrospective, cohort, case-control study of all cases of BT in a single tertiary center (1986-2009). The control group included the two subsequent full-term singleton neonates who did not experienced BT. Short-term neonatal outcome was compared between the groups including Apgar scores, NICU admission, duration of hospitalization and neurologic, respiratory and metabolic morbidity.

RESULTS

Of the 118 280 singleton full-term newborns delivered during the study period, 2874 were diagnosed with BT (24.3/1000). The most frequent types of BT were scalp injuries (63.9%, 15.5/1000) and clavicular fracture (32.1%, 7.7/1000). The following factors were found to be independent risk factors for BT: instrumental delivery (OR 7.5, 95% CI 6.3-8.9), birth weight, delivery during risk hours, parity, maternal age and neonatal head circumference. Cesarean delivery was the only factor protective of BT (OR 0.2, 95% CI 0.2-0.3). Neonates in the study group had a prolonged length of hospital stay (3.3 versus 2.7 d, p = 0.001), were more likely to be admitted to the NICU (3.9% versus 1.9%, p < 0.001), and had a higher rate of jaundice (11.9% versus 7.1%, p < 0.001) and neurological morbidity (4.7% versus 2.3%, p < 0.001).

CONCLUSION

Instrumental delivery appears to be responsible for most cases of neonatal BT.

Rapid versus stepwise negative pressure application for vacuum extraction assisted vaginal delivery

BACKGROUND

Vacuum extraction is a common technique of assisted vaginal delivery. Traditionally, it has been recommended that the pressure is increased slowly in a stepwise procedure; some have advocated rapid increases in pressure.

OBJECTIVES

To assess the efficacy and safety of rapid versus stepwise negative pressure application for assisted vaginal delivery by vacuum extraction.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (4 April 2012).

SELECTION CRITERIA

Randomized controlled trials and quasi-randomized controlled trials of rapid (within two minutes) versus stepwise (as defined by trialists) increases in negative pressure application for vacuum extraction assisted vaginal delivery.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and trial quality. The same two review authors extracted data. We entered data into Review Manager software and checked for accuracy. Data extraction and 'Risk of bias' assessment of the contact person's own study were also carried out by three independent assessors who were not involved in the new study.

MAIN RESULTS

We included two trials involving 754 participants.One new trial of 660 participants showed the same success rate of vacuum procedure of 98.2% by both methods (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.98 to 1.02).The two included trials showed significant reductions in the time between applying the vacuum cup and delivery, (one trial (74 women): mean difference (MD) -6.10 minutes, 95% CI -8.83 to -3.37 and the other trial (660 women): with median difference -4.4 minutes, 95% CI -4.8 to -4.0). The two included trials showed no significant difference in detachment rate (RR 0.85, 95% CI 0.38 to 1.86, 2 studies, 754 women), no significant difference in Apgar score below seven at one minute (RR 1.04, 95% CI 0.51 to 2.09) and five minutes (RR 1.00, 95% CI 0.29 to 3.42), no significant differences in scalp abrasions or lacerations, cephalhematoma, subgaleal hemorrhage and hyperbilirubinemia. There were no significant differences between the two methods in all secondary outcomes.

AUTHORS' CONCLUSIONS

The rapid negative pressure application for vacuum assisted vaginal birth reduces duration of the procedure whilst there is no evidence of differences in maternal and neonatal outcomes. Rapid method of negative application should be recommended for vacuum extraction assisted vaginal delivery.

Risk factors at birth for permanent obstetric brachial plexus injury and associated osseous deformities

Purpose. To examine the most prevalent risk factors found in patients with permanent obstetric brachial plexus injury (OBPI) to identify better predictors of injury. Methods. A population-based study was performed on 241 OBPI patients who underwent surgical treatment at the Texas Nerve and Paralysis Institute. Results. Shoulder dystocia (97%) was the most prevalent risk factor. We found that 80% of the patients in this study were not macrosomic, and 43% weighed less than 4000 g at birth. The rate of instrument use was 41% , which is 4-fold higher than the 10% predicted for all vaginal deliveries in the United States. Posterior subluxation and glenoid version measurements in children with no finger movement at birth indicated a less severe shoulder deformity in comparison with those with finger movement. Conclusions. The average birth weight in this study was indistinguishable from the average birth weight reported for all brachial plexus injuries. Higher birth weight does not, therefore, affect the prognosis of brachial plexus injury. We found forceps/vacuum delivery to be an independent risk factor for OBPI, regardless of birth weight. Permanently injured patients with finger movement at birth develop more severe bony deformities of the shoulder than patients without finger movement.

"Every case of asphyxia can be used as a learning example". Conclusions from an analysis of substandard obstetrical care

AIM

To propose suggestions for improvements in care based on conclusions from studies on low Apgar scores and substandard care during labor.

SETTING AND PATIENTS

Studies on infants with low Apgar scores in a general obstetric population 2004-2006 and claims for financial compensation on the behalf of infants, based on the suspicion that substandard care in conjunction with childbirth has caused severe asphyxia or neonatal death in Sweden 1990-2005.

RESULTS

The most common flaws were related to insufficient fetal surveillance, defective interpretation of cardiotocography (CTG) tracings, not acting in a timely fashion on abnormal CTG, and the incautious use of oxytocin. Besides, in half of the infants a suboptimal mode of delivery added further trauma to the already asphyxiated infant. Additionally, resuscitation was unsatisfactory in many of these infants. The most critical flaw was defective compliance with the guidelines concerning ventilation and the early paging of skilled personnel in cases of imminent asphyxia or known complications during labor. In many case reports, the documentation of the neonatal resuscitation was insufficient to enable accurate and reliable evaluation.

CONCLUSIONS

Examples of proposed improvements in care during labor are the introduction of a permanent educational atmosphere with aside time for daily educational rounds and discussion, cooperation around the use of standardized terminology in CTG interpretation, the cautious use of oxytocin, and the routine paging of a pediatrician before birth in cases of complicated delivery or imminent asphyxia. The proposed interventions need to be evaluated in clinical trials in the future.

A comparative study of feto-maternal outcome in instrumental vaginal delivery

OBJECTIVE

To compare maternal and neonatal outcomes of vacuum versus forceps application in assisted vaginal delivery.

MATERIAL AND METHOD

Women in labor with vertex presentation were delivered by vacuum and forceps. A total of 120 cases were included in this prospective study. Maternal and neonatal morbidity were compared in terms of perineal lacerations, episiotomy extension, post-partum hemorrhage, Apgar score, instrumental injuries, NICU admissions PNM etc. χ(2) test was used to analyze the data.

OBSERVATIONS

Maternal morbidity viz. episiotomy extension as well as first and second degree perineal tear were significant in the forceps group (P = 0.0001 and P = 0.02, respectively). With regards to neonatal morbidity, no statistically significant difference was noted.

CONCLUSION

Vacuum and forceps should remain appropriate tools in the armamentarium of the modern obstetrician. However, ventouse may be chosen first (if there is no fetal distress) as it is significantly less likely to injure the mother.

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

OBJECTIVE

To evaluate whether the application of rapid negative pressure for vacuum-assisted delivery is as effective and safe as the stepwise method.

DESIGN

Randomised controlled trial.

SETTING

Six centres, including university, secondary and tertiary hospitals, in Thailand.

SAMPLE

In total, 662 women were randomised to rapid and stepwise groups, with 331 women in each group.

METHODS

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.

MAIN OUTCOME MEASURES

Success rate of vacuum extraction, vacuum cup detachment rate, duration of vacuum extraction, and maternal and neonatal complications.

RESULTS

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.

CONCLUSIONS

Rapid negative pressure vacuum extraction could be performed as effectively and safely as the stepwise method, in a shorter period of time.

How often is a low Apgar score the result of substandard care during labour?

Please cite this paper as: Berglund S, Pettersson H, Cnattingius S, Grunewald C. How often is a low Apgar score the result of substandard care during labour? BJOG 2010;117:968-978. Objective To increase our knowledge of the occurrence of substandard care during labour. Design A population-based case-control study. Setting Stockholm County. Population Infants born in the period 2004-2006 in Stockholm County. Methods Cases and controls were identified from the Swedish Medical Birth Register, had a gestational age of >/=33 complete weeks, had planned for a vaginal delivery, and had a normal cardiotocographic (CTG) recording on admission. We compared 313 infants with an Apgar score of <7 at 5 minutes of age with 313 randomly selected controls with a full Apgar score, matched for year of birth. Main outcome measure Substandard care during labour. Results We found that 62% of cases and 36% of controls were subject to some form of substandard care during labour. In half of the cases and in 12% of the controls, CTG was abnormal for >/=45 minutes before birth. Fetal blood sampling was not performed in 79% of both cases and controls, when indicated. Oxytocin was provided without signs of uterine inertia in 20% of both cases and controls. Uterine contractions were hyperstimulated by oxytocin in 29% of cases and in 9% of controls, and the dose of oxytocin was increased despite abnormal CTG in 19% and 6% of cases and controls, respectively. Assuming that substandard care is a risk factor for low Apgar score, we estimate that up to 42% of the cases could be prevented by avoiding substandard care. Conclusions There was substandard care during labour of two-thirds of infants with a low Apgar score. The main reasons for substandard care were related to misinterpretation of CTG, not acting on an abnormal CTG in a timely fashion and incautious use of oxytocin.

[A comparison of maternal and fetal complications during operative vaginal delivery using Thierry's spatulas and the vacuum extractor]

OBJECTIVE

To compare short-term maternal and fetal morbidities between Thierry's spatules and the vacuum extractor.

MATERIAL AND METHODS

A retrospective study of all assisted vaginal deliveries using spatules or the vacuum extractor between January 1, 2005 and December 31, 2007 in a single, university hospital maternity.

RESULTS

There were 385 deliveries with the vacuum extractor and 332 with spatulas, among a total number of 6941 deliveries. The obstetrical conditions did not differ between the two groups (indication, level or type of presentation, duration of the second stage before extraction). The rate of episiotomy was higher in the spatules than in the vacuum extractor group (80.3 % vs 54.8 %, p < 0.0001), whereas there was a lower rate of first-to-second degree perineal lacerations (18.8 % vs 35.2 %, p < 0.0001). There was no statistically significant difference in the rate of third-to-fourth degree perineal lacerations (2.1 % vs 0.7 %, respectively, p = 0.31). Neonatal outcomes did not differ significantly between the two groups (5-minute Apgar score < 7 in 0.3 % vs 1.8 %, respectively, p = 0.75).

CONCLUSION

There were few differences in maternal and neonatal outcomes according to the type of instrument used, except for a lower episiotomy rate with vacuum extraction.

Rapid versus stepwise negative pressure application for vacuum extraction assisted vaginal delivery

BACKGROUND

Vacuum extraction is a common technique of assisted vaginal delivery. Traditionally, it has been recommended that the pressure is increased slowly in a stepwise procedure; some have advocated rapid increases in pressure.

OBJECTIVES

To assess the efficacy and safety of rapid versus stepwise negative pressure application for assisted vaginal delivery by vacuum extraction.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2008).

SELECTION CRITERIA

Randomized controlled trials and quasi-randomized controlled trials of rapid compared with stepwise increase in negative pressure application of vacuum extraction.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

One trial of 94 women was included. Duration of vacuum procedure was reduced in rapid application group (mean difference -6.10 minutes, 95% confidence interval -8.83 to -3.37). There were no significant differences in detachment rate, degree of perineal tears, Apgar score less than seven at one and five minutes, umbilical venous pH less than 7.2, scalp laceration greater than a quarter, cephalhematoma and number of tractions.

AUTHORS' CONCLUSIONS

The rapid negative pressure application for vacuum assisted vaginal birth reduces the duration of the procedure whilst there is no evidence of differences in maternal and neonatal outcome. Due to a small number of participants in the single included trial, the evidence is limited and either policy may be employed until further controlled trials provide conclusive evidence of benefit from one or other method.

Head trauma after instrumental births

Instrumental vaginal delivery involves the use of the vacuum extractor or obstetric forceps to facilitate delivery of the fetus. It is associated with substantial risk of head injury, including hemorrhage, fractures, and, rarely, brain damage or fetal death. This review article describes the different types, etiology, pathophysiology, risk factors, and clinical features of head trauma after instrumental birth, along with their management and prevention strategies.

Severe asphyxia due to delivery-related malpractice in Sweden 1990-2005

Objective

To describe possible causes of delivery-related severe asphyxia due to malpractice.

Design and setting

A nationwide descriptive study in Sweden.

Population

All women asking for financial compensation because of suspected medical malpractice in connection with childbirth during 1990–2005.

Method

We included infants with a gestational age of ≥33 completed gestational weeks, a planned vaginal onset of delivery, reactive cardiotocography at admission for labour and severe asphyxia-related outcomes presumably due to malpractice. As asphyxia-related outcomes, we included cases of neonatal death and infants with diagnosed encephalopathy before the age of 28 days.

Main outcome measure

Severe asphyxia due to malpractice during labour.

Results

A total of 472 case records were scrutinised. One hundred and seventy-seven infants were considered to suffer from severe asphyxia due to malpractice around labour. The most common events of malpractice in connection with delivery were neglecting to supervise fetal wellbeing in 173 cases (98%), neglecting signs of fetal asphyxia in 126 cases (71%), including incautious use of oxytocin in 126 cases (71%) and choosing a nonoptimal mode of delivery in 92 cases (52%).

Conclusion

There is a great need and a challenge to improve cooperation and to create security barriers within our labour units. The most common cause of malpractice is that stated guidelines for fetal surveillance are not followed. Midwives and obstetricians need to improve their shared understanding of how to act in cases of imminent fetal asphyxia and how to choose a timely and optimal mode of delivery.

Please cite this paper as:Berglund S, Grunewald C, Pettersson H, Cnattingius S. Severe asphyxia due to delivery-related malpractice in Sweden 1990–2005. BJOG 2008;115:316–323.

Shoulder dystocia related fetal neurological injuries: the predisposing roles of forceps and ventouse extractions

On the basis of 333 documented cases of permanent perinatal neurological damage, associated with arrest of the shoulders at birth, the authors conducted a retrospective study in order to evaluate the predisposing role, if any, of the utilization of extraction instruments. The investigation revealed that 35% of all injuries occurred in neonates delivered by forceps, ventouse or sequential ventouse-forceps procedures. This frequency was several-fold higher than the prevailing instrument use in the practices of American obstetricians during the same years. A high rate of forceps and ventouse extractions was demonstrable in all birth weight categories. Average weight and moderately large for gestational age fetuses underwent instrumental extractions more often than grossly macrosomic ones. This circumstance indicates that forceps and ventouse are independent risk factors, unrelated to fetal size. Their use entailed central nervous system injuries significantly more often than did spontaneous deliveries. The findings suggest that extraction procedures may be as important as macrosomia among the factors that lead to neurological damage in the child in connection with shoulder dystocia. Because they augment the intrinsic dangers of excessive fetal size exponentially, the authors consider their use in case of > or =4,000 g estimated fetal weight inadvisable. Sequential forceps-ventouse utilization further doubles the risks and is, therefore, to be avoided in all circumstances.

Vacuum and forceps training in residency: experience and self-reported competency

OBJECTIVE

Determine chief residents' experience with vacuum and forceps deliveries and self-perceived competencies with the procedures.

STUDY DESIGN

Study 1: A written questionnaire was mailed to all fourth year residents in US RRC approved Ob/Gyn programs. Study 2: The study was replicated using a web-based survey the following year. Data were analyzed with chi (2) and Wilcoxon Signed Rank tests using SPSS.

RESULTS

Surveys were received from 238 residents (20%) in Study 1 and 269 residents in Study 2 (23%, representing 50% of all residency programs). In both studies, residents reported performing significantly less forceps than vacuum deliveries. Virtually all residents wanted to learn to perform both deliveries, indicated attendings were willing to teach both, and felt competent to perform vacuum deliveries (Study 1, 94.5%; Study 2, 98.5%); only half felt competent to perform forceps deliveries (Study 1, 57.6%; Study 2, 55.0%). The majority of residents who felt competent to perform forceps deliveries reported that they would predominately use forceps or both methods of deliveries in their practice (Study 1, 75.8%; Study 2, 64.6%). The majority of residents who reported that they did not feel competent to perform forceps deliveries reported that they would predominately use vacuum deliveries in their practice (Study 1, 86.1%; Study 2, 84.2%).

CONCLUSION

Current training results in a substantial portion of residents graduating who do not feel competent to perform forceps deliveries. Perceived competency affected future operative delivery plans.

The risk of shoulder dystocia related permanent fetal injury in relation to birth weight

OBJECTIVE

To examine birth weight related risks of fetal injury in connection with shoulder dystocia.

STUDY DESIGN

The investigation was based on a retrospective analysis of 316 fetal neurological injuries associated with deliveries complicated by arrest of the shoulders that occurred across the United States.

RESULTS

The study revealed that the distribution of birthweights for the high risk shoulder dystocia population differs from the standard birthweight distribution. The relative difference per birthweight interval is used to adjust an assumed 1:1000 baseline risk of injury due to shoulder dystocia following vaginal deliveries. These adjusted risks show a need to consider new thresholds for elective cesarean delivery.

CONCLUSIONS

Current North American and British guidelines, that set 5000 g as minimum estimated fetal weight limit for elective cesarean section in non-diabetic and 4500 g for diabetic gravidas, may expose some macrosomic fetuses to a high risk of permanent neurological damage. The authors present the opinion that the mother, having been informed of the risks of vaginal versus abdominal delivery, should be allowed to play an active role in the critical management decisions.

Neonatal complications of vacuum-assisted delivery

OBJECTIVE

To assess systematically the extent of neonatal complications in a cohort of vacuum-assisted deliveries, identify risk factors associated with the occurrence of these complications, and to evaluate the usefulness of skull X-ray and transfontanellar ultrasonography after vacuum extraction.

METHODS

We reviewed a cohort of 1,123 attempted vacuum extractions of singletons performed between January 2000 and December 2004. During this period, a systematic screening using transfontanellar ultrasonography and skull X-ray was performed after vacuum extraction.

RESULTS

Among 913 successful vacuum-assisted, full-term deliveries, 25.7% were admitted to the neonatal intensive care unit. Scalp edema, cephalhematoma, and skull fracture were assessed by cranial radiography and were present in, respectively, 18.7%, 10.8%, and 5.0% of cases. Intracranial hemorrhage occurred in eight cases (0.87%). Nulliparity, a vacuum attempt at mid station, an extraction requiring more than three tractions, and dislodgment of the cup were associated with these complications but had a low predictive value.

CONCLUSION

Severe neonatal complications associated with vacuum extraction are uncommon. Systematic X-ray and ultrasonographic examination led to the discovery of asymptomatic complications. Because the clinical significance of these complications is unknown, we do not recommend them as routine screening tools.

LEVEL OF EVIDENCE

II.

Postterm delivery and risk for epilepsy in childhood

OBJECTIVE

Postterm delivery is a risk factor for perinatal complications, some of which increase risk for neurologic morbidity. We aimed to examine the association between postterm delivery and risk for epilepsy in childhood.

METHODS

We conducted a cohort study of singleton children who were born in 3 Danish counties from 1980 to 2001. Birth registry data were linked with hospital records to identify cases of epilepsy in the first 12 years of life. We included children who were born at > or = 39 gestational weeks and computed crude, age-specific, and birth weight standardized incidence rates of epilepsy. We estimated adjusted incidence rate ratios according to mode of delivery by Poisson regression.

RESULTS

Among the 277,435 nonpreterm births, 32,557 were at > or = 42 weeks, including 3396 at > or = 43 weeks. Nearly one fourth of the 2805 epilepsy cases occurred in the first year of life. In that period, birth weight standardized incidence rate ratios for epilepsy were 1.3 for birth at 42 weeks and 2.0 for birth at > or = 43 weeks, compared with birth at 39 to 41 weeks. Among children who were delivered by cesarean section, incidence rate ratios adjusted for birth weight, presentation, malformations, and county were 1.4 for birth at 42 completed weeks and 4.9 for birth at > or = 43 weeks, compared with term vaginal births. There was a similar tendency among children who were delivered with the assistance of instruments. We found no evidence for the association between postterm delivery and risk for epilepsy beyond the first year of life.

CONCLUSIONS

Prolonged gestation is a risk factor for early epilepsy; the added increase in risk for instrument-assisted and cesarean deliveries could be attributable to factors that are related to both birth complications and epilepsy.

Head injuries after instrumental vaginal deliveries

PURPOSE OF REVIEW

The types, mechanisms and clinical manifestations of head injuries (extracranial, cranial and intracranial) after instrumental delivery are described along with current evidence of their prevention and management.

RECENT FINDINGS

Asymptomatic subdural hematomas can occur in up to 6.1% of uncomplicated vaginal deliveries. Maternal nulliparity, incorrect placement of vacuum extraction cup and failed vacuum extraction are predisposing factors to subgaleal hemorrhage. Injuries associated with the vacuum devices may be minimized if the recommended limits for a safe traction force are not exceeded. There is no difference in the incidence of scalp trauma between vacuum deliveries by a rigid plastic cup (Omnicup) and the standard, silastic cup. The use of a metal cup may increase the occurrence of head injuries. Protective covers over forceps reduce the rates of neonatal facial abrasions and skin bruises. There is no difference in the incidence of cephalhematoma comparing a sequential operative vaginal delivery and a caesarean section following a failed vacuum delivery.

SUMMARY

Instrumental vaginal deliveries carry substantial risks. Only practitioners who are adequately trained or are under supervision should undertake instrumental delivery. The mode of intervention needs to be individualized after consideration of the operator's skills and experience and the clinical circumstances.

[Complications of vacuum extractor deliveries]

OBJECTIVES

To describe maternal and neonatal complications following deliveries assisted by vacuum extraction and to compare outcomes with those obtained after spontaneous vaginal delivery. We wanted to know if vacuum extractor was a risk factor by itself.

MATERIALS AND METHODS

We conducted a retrospective study of two years activity involving 4524 deliveries of which 845 (18.7%) were vacuum extractor assisted. We precisely defined maternal and neonatal complications to compare their rates in spontaneous vaginal delivery and vacuum extractor groups.

RESULTS

There were 1333 maternal complications and 114 neonatal complications. The adjusted risks of maternal complications were significantly higher in the vacuum extractor group for simple vaginal tears (OR=3.0; p<0.001), the simple perineal tears (OR=1.8; p<0.001) and third degree perineal tears (OR=2.7; p<0.01). For neonatal complications, the difference was significant for cephalhematomas (OR=10; p<0.001) and scalp abrasions (OR=53; p<0.001). No cases of skull fracture or subgaleal subaponeurotic hemorrhage were recorded.

CONCLUSION

Our rates of maternal and neonatal complications after vacuum extractor were similar to those described in the literature. We have been able to show that vacuum extraction is itself a risk factor for third degree perineal tears and cephalhematoma. However, these complications are so infrequent that the advantages of this method of extraction argue in favor of wide use in obstetrics.

Césarienne pour échec d'extraction par ventouse obstétricale : facteurs de risque et conséquences maternelles et néonatales

OBJECTIVE

To evaluate risk factors associated with failed attempts of vacuum extraction and their outcomes.

PATIENTS AND METHODS

All trial vacuum extractions (metal Minicup) from 1992 to 2000 in Besançon University Hospital Center were retrospectively analysed, namely 2447 cases. Univariate and multivariate analyses of failed vacuum extraction risk factors and descriptive analyse of outcomes were performed.

RESULTS

The rate of failed vacuum extractions was 3.47% (85/2447). A multivariate analysis showed the following independent risks factors in failed extraction: extraction above pelvic level + 2 (OR = 1.8; CI 95%: 1.1-3), newborn weight (OR = 2.9; CI 95%: 1.8-4.9), parity >2 (OR = 0.08; CI 95%: 0.01-0.6). In case of failed vacuum extraction, newborns had a significantly higher rate of Apgar score <7 at 1 min (P = 0.0002), but not at 5 min. These newborns were most regularly admitted in pediatric care units (P = 0.01).

CONCLUSION

The failed trial attempt vacuum extraction rate stays low. These failed instrumental extractions are more common in an extraction above pelvic + 2, a high fetal weight and an arrest during the second stage of labor. There is an increased adverse neonatal outcome. Clinical fetal weight estimation and diagnosis of presentation level in mother pelvis must be performed before vacuum extraction.

The influence of vacuum extractor on fetal oxygenation and newborn status

AIM

The aim of this study was to determine the effects of vacuum extractor assisted delivery on fetal oxygenation and acid-base balance.

METHODS

Sixty-one women were enrolled in the present study. The subjects were divided into two groups. Group A, consisting of 39 women, had normal vaginal deliveries. Group B, consisting of 22 women, underwent a vacuum extractor assisted vaginal delivery. Fetal arterial oxygen saturation (SpO2) monitoring was used in all women after full cervical dilatation. After delivery, umbilical artery pH, pCO2, pO2 and base deficit (BDecf) levels were determined in all neonates.

RESULTS

The mean FSpO2 value in Group A was 51.53+/-5.87% and in Group B 48.03+/-6.39% (p<0.03). The mean cord pH value in fetuses of Group A was 7.26+/-0.05, and in Group B 7.17+/-0.09. There was also a significant difference between the two groups with regards to mean pO2, pCO2 and BDecf values.

CONCLUSIONS

Vacuum assisted vaginal delivery was associated with lower fetal arterial oxygen saturation levels as well as lower cord blood pH values compared to those seen after unassisted vaginal delivery. Although decreased, however, the above parameters remained within normal ranges.

Controversies in the use of the vacuum extractor

Operative pelvic delivery is an important component of obstetrical care. Vacuum extraction assumes a prominent role, and when appropriately performed, has been proven safe and effective. However, controversies continue to exist. Historical background and review of the latest literature are presented to delineate these issues and promote consensus and direct research to continue to provide the safest means of delivery for the mother and baby.

[Trial vacuum extractor for cephalic engagement. 50 cases in French Guiana]

OBJECTIVE

Considering a population with an African culture traditionally opposed to a caesarean section, vertex engagement with a vacuum extractor could be a good alternative.

PATIENTS AND METHODS

In a retrospective study of 50 cases of trial engagement with a vacuum extractor in French Guyana, there were 94% of vaginal deliveries.

RESULTS

A high level of shoulder dystocia (14%) was noted, and the failure of this technique was the consequence of disproportions between foetus and pelvis that had not been correctly diagnosed.

CONCLUSION

In this article, feasibility and obstetrical conditions to carry out a trial engagement with a vacuum extractor are discussed.