Maternal and neonatal morbidity in instrumental deliveries with the Kobayashi vacuum extractor and low forceps

Secondary repair of the perineum following childbirth

The aim of the study was to evaluate secondary repair of the perineum following perineal trauma at childbirth. Patients who underwent secondary repair reported with symptoms of superficial dyspareunia, vulvo-vaginal pain, vaginal stenosis and broken or gaping wound. The study included 103 women over a 16-year period that underwent refashioning of the perineum at Northwick Park Hospital by the same surgeon. Among the cases, 81.6% were nulliparous and 18.4% were multiparous. Labour was induced in 30.1%, and 38% of the women required instrumental delivery. The length of the second stage of labour was 89 +/- 60 min for nulliparae and 50 +/- 48 min for multiparae. In 53.4% of the women, an episiotomy was performed. Catgut sutures were used in 69% of primary repairs. Predisposing factors for the need for secondary repair included nulliparity, forceps delivery, episiotomy, prolonged second stage of labour, surgeons' inexperience and the choice of suture material. Secondary repair is associated with a good result. A majority of women who required refashioning of the perineum for superficial dyspareunia presented late after the onset of the problem. In carefully selected women, such cases of superficial dyspareunia are easily treatable and surgery needs to be considered as an option.

Guidelines for Operative Vaginal Birth

OBJECTIVE

To provide guidelines for operative vaginal birth in the management of the second stage of labour.

OPTIONS

Non-operative techniques, episiotomy, and Caesarean section are compared to operative vaginal birth. outcome: Reduced fetal and maternal morbidity and mortality.

EVIDENCE

MEDLINE and Cochrane databases were searched using the key words 'vacuum' and 'birth' as well as 'forceps' and 'birth' for literature published in English from January 1970 to June 2004. The level of evidence and quality of recommendations made are described using the Evaluation of Evidence from the Canadian Task Force on the Periodic Health Examination.

RECOMMENDATIONS

1. Non-operative interventions such as one-to-one support, partogram use, oxytocin use, and delayed pushing in women using epidurals will decrease need for operative birth. (I-A) 2. Manual rotation may be used alone or in conjunction with instrumental birth with little or no increased risk to the pregnant woman or to the fetus. (III-B) 3. Routine episiotomy is not necessary for an assisted vaginal birth. (II-1E) 4. When operative intervention in the second stage of labour is required, the options, risks, and benefits of vacuum, forceps, and Caesarean section must be considered. The choice of intervention needs to be individualized, as one is not clearly safer or more effective than the other. (II-B) 5. Failure of the chosen method, vacuum and/or forceps, to achieve delivery of the fetus in a reasonable time should be considered an indication for abandonment of the method. (III-C) 6. Adequate clinical experience and appropriate training of the operator are essential to the safe performance of operative deliveries. Hospital credentialing boards should grant privileges for performing these techniques only to an appropriately trained individual who demonstrates adequate skills. (III-C).

VALIDATION

The Clinical Practice Obstetrics Committee and Executive and Council of the Society of Obstetricians and Gynaecologists of Canada approved these guidelines.

Immediate Maternal and Neonatal Effects of Forceps and Vacuum-Assisted Deliveries

OBJECTIVE

To estimate the differences in immediate maternal and neonatal effects of forceps and vacuum-assisted deliveries.

METHODS

We conducted a medical record review of all forceps and vacuum-assisted deliveries that occurred from January 1, 1998, to August 30, 1999, at Winthrop-University Hospital. Maternal demographics and delivery characteristics were recorded. Maternal outcomes, such as use of episiotomy and presence of lacerations, were studied. Neonatal outcomes evaluated were Apgar scores, neonatal intensive care unit admissions, cephalohematomas, instrument marks and bruising, and caput and molding.

RESULTS

Of 508 operative vaginal deliveries, 200 were forceps and 308 were vacuum assisted. Forceps were used more often than vacuum for prolonged second stage of labor (P =.001). There was a higher rate of epidural (P =.02) and pudendal (P <.001) anesthesia, episiotomies (P =.01), maternal third- and fourth-degree perineal (P <.001) and vaginal lacerations (P =.004) with the use of forceps, whereas periurethral lacerations were more common in vacuum-assisted (P =.026) deliveries. More instrument marks and bruising (P <.001) were found in the neonates delivered by forceps, whereas there was a greater incidence of cephalohematomas (P =.03) and caput and molding (P <.001) in the neonates delivered with vacuum. Multivariable logistic regression analysis showed that forceps use was associated with an increase in major perineal and vaginal tears (odds ratio [OR] 1.85; 95% confidence interval [CI] 1.27, 2.69; P =.001), an increase in instrument marks and bruising (OR 4.63; 95% CI 2.90, 7.41; P <.001) and a decrease in cephalohematomas (OR 0.49; 95% CI 0.29, 0.83; P =.007) compared with the vacuum.

CONCLUSIONS

Maternal injuries are more common with the use of forceps. Neonates delivered with forceps have more facial injuries, whereas neonates delivered with vacuum have more cephalohematomas.

LEVEL OF EVIDENCE

II-3

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.

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.

Third degree obstetric perineal tears: risk factors and the preventive role of mediolateral episiotomy

OBJECTIVE

To determine risk factors for third degree obstetric perineal tears and to give recommendations for prevention.

DESIGN

Retrospective case control study.

SETTING

A teaching hospital in The Netherlands.

PARTICIPANTS AND METHODS

One hundred and twenty cases of vaginal delivery complicated by third degree perineal tear and 702 uncomplicated vaginal deliveries were compared, with respect to possible risk factors.

RESULTS

In a multivariate model high birthweight, forceps delivery, induced labour, epidural anaesthesia and parity were risk factors for anal sphincter tear. In addition, mediolateral episiotomy was associated with fewer sphincter injuries. Separate analysis of nulli- and multiparous women demonstrated that high birthweight and epidural anaesthesia (increased risk) and mediolateral episiotomy (decreased risk) were factors associated with anal sphincter tear only in nulliparous women.

CONCLUSIONS

We found several risk factors for anal sphincter tear. Nulliparous women are at higher risk than multiparous women. Mediolateral episiotomy may be sphincter-saving especially in nulliparous women and therefore prevent them from chronic faecal incontinence.

Intervention during labor: risk factors associated with complete tear of the anal sphincter

Among 41,200 consecutive deliveries there were 152 cases of complete tear of the anal sphincter (complete tear). In a case-control design, the association between interventions during labor (forceps, vacuum extraction, use of oxytocin and prostaglandins and mediolateral episiotomy) and complete tear, were evaluated by confounder control using multiple logistic regression analysis. Controls chosen were the patients delivering just before and after the index patient with complete tear. Use of Kielland forceps, mediolateral episiotomy, shoulder dystocia and nulliparity were significantly associated with complete tear. Maternal age, presentation in labor, duration of second stage of labor and the indication for instrumental deliveries and episiotomy had no significant association with complete tear.

Risk factors for third-degree and fourth-degree perineal lacerations in forceps and vacuum deliveries

Third- and fourth-degree perineal lacerations occur frequently during operative vaginal deliveries. To identify risk factors for lacerations, 2832 consecutive forceps and vacuum extraction deliveries were analyzed. Third- and fourth-degree lacerations occurred in 30% of deliveries. Multiple logistic regression was used to control for intercorrelation between potential risk factors. Factors associated with increased risk for third- and fourth-degree lacerations were midline episiotomy, nulliparity, second-stage arrest, occipitoposterior position, low or mid station, use of forceps instead of vacuum, use of local anesthesia, and Asian race. When these factors were controlled, there was no effect of birth weight, faculty versus resident operator, gestational age, abnormalities of first-stage labor, or several other factors. Prevention of perineal lacerations requires that the operator identify the patient at risk. Possible options for management of high-risk patients include use of mediolateral episiotomy or no episiotomy, use of vacuum extraction instead of forceps, and use of conduction anesthesia.