Caesarean Section for Fetal Distress, the Interval From Decision to Delivery, and the Relative Risk of Poor Neonatal Condition

Defining the decision-to-delivery interval at caesarean section: narrative literature review and proposal for standardisation

The decision-to-delivery interval is a widely used term at non-elective caesarean section. While the definition may appear self-evident, there is no universally agreed consensus about when this period begins and ends. We reviewed the literature for original research utilising the terms 'decision-to-delivery', 'decision-to-incision' or 'incision-to-delivery' and examined definitions used for decision, delivery, incision, as well as any additional time intervals that were assessed. Our analysis demonstrated an inconsistent non-standardised approach to defining these intervals, which might have clinical practice and medicolegal ramifications. We propose that the decision-to-delivery interval should be defined as follows: the interval between the time at which the senior obstetrician makes the decision that a caesarean section is required and the time at which the fetus (or first fetus in the case of multiples) is delivered. The decision time should ideally be recorded contemporaneously in the medical notes or partogram.

The decision-to-delivery interval in emergency Caesarean sections and its correlation with perinatal outcome: evidence from 204 deliveries in a developing country

The international standard decision-to-delivery interval (DDI) for emergency Caesarean sections (CSs) is ≤ 30 minutes but there is little evidence to support this recommendation. The aim of this study was to evaluate DDI for emergency CS and its relationship to perinatal outcome. We undertook a prospective observational study of consecutive cases of emergency CS. Perinatal outcomes were recorded as: Apgar score; neonates requiring admission; and perinatal deaths. The relation between DDI and perinatal outcome was analysed using chi-square and one way analysis of variance (ANOVA). Of 204 pregnancies observed, 19% of deliveries were achieved in ≤ 30 minutes. The mean DDI was 42.5 ± 19.4 minutes. There was no difference between the perinatal outcome for babies with DDI of ≤ 30 versus 31-60 minutes. There was a significantly higher risk of poor perinatal outcome for babies with DDI > 60 minutes. The perinatal outcome between DDI of ≤ 30 and 31-60 minutes was statistically not different. However, the ≤ 30 minutes DDI should remain the gold standard.

Emergency caesarean section: influences on the decision-to-delivery interval

RCOG/NICE guidelines recommend that, for fetal compromise in labour, delivery should be accomplished ideally within 30 minutes. In this study, we investigated the factors which affect the decision-to-delivery (DD) intervals for emergency caesareans. To achieve this, prospective data were collected for all grade 1 and 2 caesareans performed on a busy labour ward over 12 months. We found that the ratio of labouring women to midwives had a significant effect on the DD intervals, which were significantly prolonged when 1 : 1 care was not provided (P < 0.001). The observed effect resulted exclusively from a prolonged transfer time to theatre. General anesthesia use shortened the DD interval for grade 1 caesareans (P < 0.001) and was more likely to be used during the day shift (P < 0.009). We conclude that midwifery staffing levels and the form of anaesthesia employed influence on DD intervals for the most urgent caesarean sections.

Cesarean section for suspected fetal distress, continuous fetal heart monitoring and decision to delivery time

OBJECTIVE

To find out the efficacy of continuous fetal heart monitoring by analyzing the cases of cesarean section for nonreassuring fetal heart in labor, detected by cardiotocography (CTG) and correlating these cases with perinatal outcome. To evaluate whether a 30 minute decision to delivery (D-D) interval for emergency cesarean section influences perinatal outcome.

METHODS

This was a prospective observational study of 217 patients who underwent cesarean section at > or = 36 weeks for non-reassuring fetal heart in labor detected by CTG. The maternal demographic profile, specific types of abnormal fetal heart rate tracing and the decision to delivery time interval were noted. The adverse immediate neonatal outcomes in terms of Apgar score <7 at 5 minutes, umbilical cord thornH <7.10, neonates requiring immediate ventilation and NICU admissions were recorded. The correlation between non-reassuring fetal heart, decision to delivery interval and neonatal outcome were analyzed.

RESULTS

Out of 3148 patients delivered at > or = 36 weeks, 217 (6.8%) patients underwent cesarean section during labor primarily for non-reassuring fetal heart. The most common fetal heart abnormality was persistent bradycardia in 106 (48.8%) cases followed by late deceleration in 38 (17.5%) cases and decreased beat to beat variability in 17 (7.8%) cases. In 33 (15.2%) babies the 5 minutes Apgar score was <7 out of which 13 (5.9%) babies had cord thornH <7.10. Thirty three (15.2%) babies required NICU admission for suspected birth asphyxia. Rest 184 (84.7%) neonates were born healthy and cared for by mother. Regarding decision to delivery interval of < or =30 minutes versus >30 minutes, there was no significant difference in the incidence of Apgar score <7 at 5 minutes, cord pH <7.10 and new born babies requiring immediate ventilation. But the need for admission to NICU in the group of D-D interval < or = 30 minutes was significantly higher compared to the other group where D-D interval was >30 minutes.

CONCLUSION

Non-reassuring fetal heart rate detected by CTG did not correlate well with adverse neonatal outcome. There was no significant difference in immediate adverse neonatal outcome whether the D-D time interval was < or = 30 minutes or >30 minutes; contrary to this, NICU admission for suspected birth asphyxia in </= 30 minutes group was significantly higher.

Cohort study of the decision to delivery interval and neonatal outcome for emergency operative vaginal delivery

OBJECTIVE

The purpose of this study was to assess whether a target decision to delivery interval (DDI) is appropriate for 'emergency' operative vaginal delivery and whether this would reduce adverse neonatal outcomes.

STUDY DESIGN

We performed a retrospective cohort study of 1021 singleton term babies who experienced operative delivery for 'fetal distress' in the second stage of labor between 1998 and 2003 in Dundee, Scotland.

RESULTS

The mean DDI in a labor room was 14.5 minutes (SD 9.5) compared to 30.0 minutes (SD 14.6) in an operating room. Shorter DDIs were associated with use of local rather than regional or general anesthesia. There were no significant differences in rates of low Apgar score (< 7 at 5 min) OR 0.99 (95% CI 0.27, 3.71), fetal acidosis (pH < 7.10) OR 1.24 (0.78, 1.99), neonatal resuscitation OR 1.00 (95% CI 0.65, 1.53), or admission to NICU OR 0.53 (95% CI 0.27, 1.03) for babies delivered within 15 minutes compared to greater than 15 minutes. The outcomes were similar for a 30-minute threshold. The DDIs for forceps and vacuum deliveries were similar as were neonatal outcomes.

CONCLUSION

A DDI of 15 minutes is an achievable target for operative vaginal delivery in a labor room with 30 minutes for delivery in an operating room; however, setting arbitrary limits is unlikely in itself to prevent adverse neonatal outcomes.

Evaluating the decision-to-delivery interval in emergency caesarean sections

OBJECTIVE

To assess the interval between the decision to carry out an emergency caesarean section and delivery, and to determine whether this interval can be shortened.

STUDY DESIGN

A retrospective study was performed in a French maternity hospital over a 6-month period. All caesarean sections performed during labour were included. These caesarean sections were divided into two groups according to Lucas's classification: (1) emergency and urgent caesarean sections and (2) scheduled caesarean sections.

RESULTS

The mean decision--to--delivery interval was 39.5 min in the first group and 55.9 min in the second group. It was mainly influenced by the time taken to get the patient into theatre. The mean decision-to-operating theatre interval accounted for 45.6 and 53.8% of the mean decision-to delivery-interval, respectively.

CONCLUSION

The recommended interval of 30 min is not routinely achieved. Improving communication within the perinatal team could decrease the decision--to--operating theatre interval and should be promoted.

The decision to delivery interval in emergency and non-urgent cesarean sections

OBJECTIVE

The aim of this study was to assess the decision to delivery interval (DDI) in our obstetric unit in comparison to current recommendations.

STUDY DESIGN

A retrospective analysis of all non-elective cesarean sections during a 10 months period in a delivery ward of a university tertiary health care facility was performed. The DDI was compared between emergency and non-urgent cesarean sections.

RESULTS

The DDI was 25.8 +/- 10.8 +/- and 46.2 +/- 19.9 min in the emergency and non-urgent cesareans, respectively (P < 0.01). In the emergency group, 71% delivered within 30 min compared to 35% in the non-urgent group (P < 0.05) and in the emergent-crash group 100% delivered within 30 min compared to 59% in the emergent-non-crash group (P < 0.05). No correlation was found between the DDI and umbilical artery pH or Apgar score at 1 or 5 min in infants of each cesarean group.

CONCLUSION

The proposed 30 min DDI standard was achieved in 100, 71, 47 and 35% of emergent-crash, emergent, emergent-non-crash and non-urgent cesareans sections, respectively.

What is a reasonable time from decision-to-delivery by caesarean section? Evidence from 415 deliveries

OBJECTIVE

To determine how long it takes from the decision to achieve delivery by non-elective caesarean section (DDI), the influences on this interval, and the impact on neonatal condition at birth.

DESIGN

Twelve months prospective data collection on all non-elective caesarean sections.

METHODS

Prospective collection of data relating to all caesarean sections in 1996 in a major teaching hospital obstetric unit was conducted, without the knowledge of the other clinicians providing clinical care. Details of the indication for section, the day and time of the decision and the interval till delivery were recorded as well as the seniority of the surgeon, and condition of the baby at birth.

RESULTS

The mean time from decision-to-delivery for 100 emergency intrapartum caesarean sections was 42.9 minutes for fetal distress and 71.1 minutes for 230 without fetal distress (P < 0.0001). For 22 'crash' sections the mean time from decision-to-delivery was 27.4 minutes; for 13 urgent antepartum deliveries for fetal reasons it was 124.7 minutes and for 21 with maternal reasons it was 97.4 minutes. The seniority of the surgeon managing the patient did not appear to influence the interval, nor did the time of day or day of the week when the delivery occurred. Intrapartum sections were quicker the more advanced the labour, and general anaesthesia was associated with shorter intervals than regional anaesthesia for emergency caesarean section for fetal distress (P < 0.001). Babies born within one hour of the decision tended to be more acidaemic than those born later, irrespective of the indication for delivery. Babies tended to be in better condition when a time from decision-to-delivery was not recorded than those for whom the information had been recorded.

CONCLUSION

Fewer than 40% intrapartum deliveries by caesarean section for fetal distress were achieved within 30 minutes of the decision, despite that being the unit standard. There was, however, no evidence to indicate that overall an interval up to 120 minutes was detrimental to the neonate unless the delivery was a 'crash' caesarean section. These data thus do not provide evidence to sustain the recommendation of a standard of 30 minutes for intrapartum delivery by caesarean section.

Decision to delivery intervals for assisted vaginal vertex delivery

OBJECTIVE

To describe the time interval between decision for assisted vaginal delivery and the birth of the baby in different clinical circumstances.

DESIGN

A prospective analysis of 225 consecutive women with a singleton fetal cephalic presentation in the second stage of labour requiring an operative vaginal delivery for various reasons.

SETTING

A maternity unit in a district general hospital delivering more than 6,000 women annually.

MAIN OUTCOME MEASURES

The decision to delivery interval and the immediate and short term maternal and neonatal outcomes according to indication for operative vaginal delivery.

RESULTS

The mean (SD) decision to delivery interval was 34.4 minutes (28.3) with a range of 5 to 101 minutes. For those delivered because of suspected fetal distress, the interval of 26.5 minutes (14.0) was significantly shorter than for those performed without fetal distress 39.5 minutes (19.0) (P < 0.0001); for cases with fetal distress, forceps were significantly quicker at 23.3 minutes (14.3) than the ventouse 29.2 minutes (13.2) (P = 0.04). The longer the interval in cases of fetal distress the less favourable the condition of the neonate at birth, although this trend did not reach statistical significance and was not seen for deliveries expedited for other reasons. Perineal repair was required following 96% forceps deliveries compared with 87% ventouse (P = 0.015). Perineal trauma was not influenced by the interval between decision and delivery.

CONCLUSIONS

If speed of delivery is important, use of forceps results in a quicker birth than use of the ventouse, without any compromise to the condition of the baby at delivery, and with similar rates of perineal trauma.

Intrapartum fetal surveillance

Intrapartum hypoxia was thought to contribute to the incidence of cerebral palsy, seizures and mental retardation. Electronic fetal monitoring was expected to prevent or reduce this incidence. Electronic fetal monitoring has a high false positive rate and fetal blood sampling, which is an invasive procedure, only allows an intermittent assessment. Efforts are being made to improve fetal heart rate analysis and clinical management. Fetal pulse oximetry, fetal electrocardiogram waveform analysis and the intermittent measurement of lactate levels by fetal blood sampling may become established as an adjunct to electronic fetal monitoring.

The mortality and morbidity associated with umbilical cord prolapse

OBJECTIVE

To examine the management of cord prolapse and its morbidity and mortality.

DESIGN

Retrospective study of consecutive babies born after cord prolapse, identified using the Oxford Obstetric Data System, and those with registered handicap, identified by the Oxford Region Register of Early Childhood Impairments.

SETTING

District maternity hospital managing more than 6000 deliveries annually.

SUBJECTS

One hundred and thirty-two babies born after the identification of cord prolapse in the John Radcliffe Hospital between January 1984 and December 1992.

MAIN OUTCOME MEASURES

Survival rates, condition at birth assessed by Apgar scores at 1 and 5 minutes and blood gas values on cord blood samples, and incidence of major handicap at three years of age.

RESULTS

The incidence of cord prolapse was 1 in 426 total births. There were six stillbirths and six neonatal deaths. One baby died as a result of birth asphyxia. The uncorrected perinatal mortality rate was 91 per 1000. Of 120 survivors, only one baby was known to suffer a major neurological handicap. Electronic cardiotocographs aided the diagnosis of cord prolapse in 41% of cases. Apgar scores were better with a shorter diagnosis to delivery interval, but cord gas results did not correlate well with Apgar scores or the diagnosis to delivery interval.

CONCLUSIONS

Cord prolapse occurs with a relatively stable incidence in this population irrespective of changes in obstetric practices. Despite the high incidence of ominous cardiotocographs, low Apgar scores and acidaemia on blood gas analysis, the fetal outcome is not as poor as might be expected and mortality is predominantly attributable to congenital anomalies and prematurity rather than birth asphyxia.

Emergency caesarean section during labour: response times and type of anaesthesia

Eighteen percent of 212 consecutive emergency caesarean sections at term were classified as truly 'urgent' (requiring delivery within 20 min). The interpretation of the intrapartum cardiotocographs was generally accurate, although after an independent review of the tracings six cases classified originally as 'urgent' had Krebs scores > 4. Among the 'urgent' cases the median total time interval from decision to operate to delivery of the baby was 25 min (IQR between 20 and 33). One-third of the 'urgent' cases had total time intervals exceeding 30 min and the longest delay was 56 min. Acidotic FBS results and antepartum haemorrhage produced most rapid responses. Nine percent of the babies required SCBU admission. Seven percent of the patients in the study had general anaesthetics for their operations. Although the achievement of a total time interval delay of between 20 and 30 min was possible with regional anaesthetic techniques, a general anaesthetic was needed to obtain a time interval of less than 20 min. In conclusion, regional anaesthetic techniques can provide response times which are acceptable for the majority of 'urgent' caesarean sections with the administration of a general anaesthetic occasionally justified in the fetal interest.