Original Article ⅢⅢⅢⅢⅢⅢⅢⅢⅢⅢⅢⅢⅢⅢ Relationship Between Fetal Monitoring and Resuscitative Needs: Fetal Distress Versus Routine Cesarean Deliveries

Robert Posen, DO Philippe Friedlich, MD CONCLUSION: Linda Chan, PhD In our study group, infants with fetal distress had significantly greater David Miller, MD intervention needs than infants without fetal distress. Journal of Perinatology 2000; 2:101–104.

BACKGROUND: There is debate as to whether pediatricians should be present at all cesar- Historically, pediatricians (including neonatologists) have been ean deliveries. Little published data exist regarding the differences in present at almost all cesarean sections, from routine non-high risk to resuscitative needs of infants delivered by cesarean section for “fetal complicated high risk, to evaluate the neonate, perform a preliminary distress” versus those without this diagnosis. physical examination, and supervise any resuscitative efforts that may be required. In the private medical sector, with the increased need to OBJECTIVE: control cost, many third-party payers have questioned whether or not To describe the differences in resuscitative and immediate postnatal it is cost-efficient to have a pediatrician present at all cesarean section intervention needs for neonates with fetal distress delivered by cesarean deliveries, especially “low-risk cesarean sections.” Some hospitals section and those without fetal distress delivered in the same manner. have left the decision of whether or not to have a pediatrician in at- Also, to devise an evaluation tool to assess and compare levels of neona- tendance to the obstetrician of record in each individual case. It is tal resuscitation between infants and groups of infants. then up to the obstetrician to examine all maternal and fetal factors, assess the results of fetal monitoring, and decide whether pediatrician METHODS: presence is warranted. Typically, these factors include maternal medi- The delivery records of 1411 term infants delivered by cesarean section cal history, history of pregnancy complications, electronic fetal moni- after uncomplicated pregnancies at Los Angeles County/University of toring, and progression of labor. In the past, these parameters were Southern California Medical Center from March 3, 1995 through March used mainly to decide on obstetrical intervention before delivery, but 8, 1997 were examined retrospectively. Apgar scores and resuscitative not as an indicator of need for perinatal resuscitation. It is unclear needs were assigned to a newly devised, weighted scoring system. Resusci- whether current standard fetal monitoring techniques can accurately tation subscores and total resuscitation scores were compared using predict a greater risk or need for perinatal resuscitation when perfor- non-parametric methods. mance of a cesarean section is based on maternal-fetal monitoring. In addition, is there a significant clinical and statistical difference in RESULTS: adverse outcome (i.e., need for newborn resuscitation or intervention) ϭ The fetal distress group (n 80) had a significantly greater resuscita- in infants born by cesarean section with “fetal distress” versus those Ͻ Ͻ ϭ tive needs mean score (p 0.001) and subscores (p 0.001 to p born by cesarean section without fetal distress? Jacob and Pfenninger1 ϭ 0.004) than did the non-fetal distress group (n 419). Of the non-fetal compared the need for vigorous resuscitation of infants delivered by distress group, 48.7% still received some active form of intervention. uncomplicated repeat cesarean section under regional anesthesia or uncomplicated cesarean section for nonprogressive labor under regional anesthesia with matched non-high-risk vaginal deliveries. Division of Newborn Medicine (R. P., P. F.), Department of Pediatrics, University of South- They concluded that routine cesarean sections without signs of fetal ern California School of Medicine, Los Angeles, CA; Department of Biostatistics (L. C.), Uni- distress may not need a pediatrician in attendance. versity of Southern California School of Medicine, Los Angeles, CA; and Division of Mater- nal-Fetal Medicine (D. M.), Department of Obstetrics and Gynecology, University of We sought to determine whether there was a difference in the Southern California School of Medicine, Los Angeles, CA. degree of neonatal resuscitation and intervention required by infants This paper was presented in part at the American Academy of Pediatrics Annual Conference, with fetal distress delivered by cesarean section versus infants without New Orleans, LA, November 1, 1997. Resuscitative needs and outcomes of fetal distress and non-fetal distress cesarean Address correspondence and reprint requests to Robert Posen, DO, Neonatal Intensive Care Unit, Huntington Memorial Hospital, 100 West California Boulevard, Pasadena, CA 91109- deliveries were compared to determine whether pediatrician cesarean attendance is 7013. E-mail address: [email protected] always warranted.

fetal distress delivered by cesarean section after excluding as many admission. A weighted scoring sheet was devised (see Appendix A) complicating factors as possible. We hypothesized that, excluding before the analysis in which a higher score reflected a greater need for pre-existing maternal/fetal complications other than fetal distress, there resuscitation or an undesirable outcome; within each category of is no difference in the resuscitative needs of full-term infants delivered outcome or resuscitation, successively higher needs or successively by routine cesarean section versus cesarean section for fetal distress. poorer Apgar scores are given a higher weighted subscore. The scoring sheet was intended to make the assessment of resuscitative needs as METHODS consistent and objective as possible. The scoring in each category was Study Site and Patient Population weighted to avoid an equivalence in severity between, for example, an This study was conducted at Women’s and Children’s Hospital of Los infant who required temporary bag-and-mask oxygen administration Angeles County/University of Southern California Medical Center (Los who was subsequently brought to the NICU and an infant who re- Angeles, CA). The delivery record computer database of all infants quired intubation and was subsequently admitted to the NICU; the delivered by cesarean section between August 3, 1995 and March 8, latter example would score higher on the resuscitative needs score 1997 was reviewed. The delivery record contains coded information on than the former. Although the weighting of scores in each category obstetric and fetal risk factors and complications, the delivery method, was arbitrary to a large extent, the scoring was applied consistently indication for delivery method, delivery complications, Apgar scores, and systematically. Resuscitation subscores (separate for Apgar scores, and resuscitation requirements for the neonate. This coded informa- ventilatory resuscitation, circulatory resuscitation, and NICU admis- tion was entered on computer for future statistical analysis and re- sion) were calculated. Subscores and a total resuscitation score were view. Newborn inclusion criteria were a gestational age (by best esti- assigned to each neonate, reflecting the resuscitative needs and out- mate) of Ն37 weeks and delivery by cesarean section. Exclusion come, and the scores obtained were the basis for comparison between criteria were more comprehensive because of the desire to keep the the two groups (distress versus no antenatal diagnosis of distress). The fetal distress group and no fetal distress group as similar as possible Mann-Whitney rank-sum test was used to compare the mean scores of on all clinical levels except for the presence or absence of “distress.” the two groups. Because many prenatal maternal and fetal conditions such as gestational diabetes, multiple gestation pregnancy, very low birth weight RESULTS and intrauterine growth retardation, Rh isoimmunization, and so on are associated with increased fetal risk and hence possible fetal dis- At Women’s Hospital between March 3, 1995 and March 8, 1997, there tress, these cases were excluded, as pediatricians are still typically were 7452 deliveries. Of these deliveries, 1411 (18.9%) were cesarean called to be present for these deliveries. The exclusion criteria in- sections. After application of the inclusion and exclusion criteria to cluded but were not limited to: any antenatally diagnosed fetal anom- the cesarean section deliveries, there were 80 infants with a designa- aly, pathology or illness; any significant maternal illness, pathology, tion of fetal distress and 419 infants without this designation included or disease (including gestational diabetes classes A1 through R, preg- in the analysis. The mean total weighted resuscitation score was 4.46 ϭ ϭ nancy-induced hypertension, and sepsis/prenatally diagnosed amnio- (SD 5.15) for the fetal distress group and 2.00 (SD 3.33) for the nitis); prematurity; known significant intrauterine growth retarda- non-fetal distress group. Whereas 53 of the 80 infants with fetal dis- tion; significant maternal infection (except amnionitis diagnosed tress (66.3%) received at least some form of intervention (least inter- perinatally); and multiple gestation pregnancy (any pregnancy other vention possible was transient administration of “blow-by” supple- than singleton). Fetal distress was defined by the presence on the mental oxygen), 204 of the 419 non-fetal distress infants (48.7%) delivery record of any of the following terms: fetal distress, non-reas- received some form of intervention in the delivery room after cesarean suring fetal heart rate, non-reassuring fetal monitoring strip, repeti- delivery. In addition, 22.5% (18 of 80) of the fetal distress group neo- tive deep variable decelerations, repetitive late decelerations, and fetal nates were admitted for various reasons to the NICU, and 15.3% (64 of bradycardia. No differentiation was made between external and inter- 419) of the non-fetal distress group infants were admitted. It is worth nal fetal monitoring. Further, for fetal distress group inclusion pur- noting that although 3 of 80 (3.8%) infants in the fetal distress group Ն poses, an infant did not need fetal distress entered as the primary had weighted resuscitation scores of 15 (a moderately high score reason for cesarean delivery as long as this term or any of the other on this scale), there were also 4 of 419 (1%) infants in the non-fetal Ն terms mentioned above were included in the delivery record under distress group with scores of 15. “fetal complications.” Table 1 shows the means and SDs of the weighted resuscitation subscores for both the fetal distress and non-fetal distress groups, as Data Collection and Analysis well as the means and SDs of the total weighted resuscitation scores Resuscitative needs and outcome were assessed and recorded for each for both groups. The means for the fetal distress group were signifi- patient included in the analysis according to the level of ventilation cantly higher (p Ͻ 0.001 to p ϭ 0.004) than those for the non-fetal support/oxygenation needs, need for circulatory support, need for distress group on almost all subscores and the total resuscitation fluid resuscitation, need for resuscitation medications, Apgar scores at score. The difference between the two groups was not significant on 1 minute and 5 minutes, and neonatal intensive care unit (NICU) the circulation subscore and on the NICU admission subscore.

102 Journal of Perinatology 2000; 2:101–104 Fetal Monitoring and Resuscitative Needs Posen et al.

Table 1 Resuscitation Subscores and SDs for Fetal Distress and Non-Fetal Distress Groups Subscore category Fetal distress group (n ϭ 80) Non-fetal distress group (n ϭ 419) Significance (Mann-Whitney test) (mean Ϯ SD) (mean Ϯ SD)

Inverted Apgar score (1 minute) 2.00 Ϯ 2.07 0.89 Ϯ 1.18 p Ͻ 0.001 Inverted Apgar score (5 minute) 0.39 Ϯ 0.92 0.11 Ϯ 0.42 p ϭ 0.002 Inverted Apgar total score 1.19 Ϯ 1.42 0.50 Ϯ 0.73 p ϭ 0.004 Ventilation score 2.49 Ϯ 3.17 1.02 Ϯ 1.79 p Ͻ 0.001 Circulation score 0.08 Ϯ 0.67 0.01 Ϯ 0.29 p ϭ 0.190 NICU admission score 0.68 Ϯ 1.26 0.46 Ϯ 1.08 p ϭ 0.110 Total resuscitation score 4.46 Ϯ 5.15 2.00 Ϯ 2.77 p Ͻ 0.001

DISCUSSION ability of these positive findings to predict abilities to detect the fetuses truly at risk. In contrast, what is the likelihood of an adverse neonatal Pediatrician and/or neonatologist attendance at all cesarean sections outcome given negative antepartum monitoring (i.e., no fetal dis- is standard at some hospitals, whereas at other hospitals only specific 13 indications (such as prematurity, fetal distress, presence of meconium tress)? Nageotte et al. studied adverse perinatal outcomes in women in the amniotic fluid, etc.) warrant pediatrician attendance. The who had either a negative contraction stress test or a negative modi- purpose of physician attendance or the presence of other highly fied biophysical profile. Adverse outcomes were observed in 5.1% of trained resuscitation personnel (i.e., a neonatal nurse specialist, neo- patients whose last test was a negative modified biophysical profile, natal respiratory therapist specialist, etc.) is to be prepared for possible and in 7% of patients whose last test was a negative contraction stress neonatal resuscitative needs. Among the intrapartum risk factors for test; it was concluded that the frequency of adverse outcomes was predicting possible resuscitative needs listed in the American Academy equivalent after either type of negative test. of Pediatrics/American Heart Association textbook on neonatal resus- Women’s and Children’s Hospital of Los Angeles County/Univer- citation (1995) are the following: emergency cesarean section, pro- sity of Southern California Medical Center had a delivery rate of ϳ longed second stage of labor, nonreassuring fetal heart rate patterns, 4000 to 6000 per year during the time of this study. Of these deliv- ϳ and meconium-stained amniotic fluid. Accordingly, not all infants eries, the cesarean section rate was 15% to 17% (compared with the born by cesarean section require resuscitation. Ng et al.2 found that national rate of 18% to 25%). Pediatric housestaff and/or neonatology the incidence of active resuscitative needs of infants with cephalic fellows attend all cesarean sections. Fetal distress as an indicator for presentation born by cesarean section (elective and emergent) under cesarean section includes “non-reassuring fetal heart rate,” “repeti- epidural anesthesia without fetal distress was equivalent to the quoted tive deep variables,” “repetitive late decelerations,” “fetal bradycar- incidence for spontaneous normal vaginal delivery. However, they dia,” and “fetal tachycardia;” these findings often lead to the decision found an increased resuscitative need for infants delivered by cesarean to proceed with cesarean section, because these deliveries may be section under general anesthesia and for babies delivered by cesarean associated with a higher incidence of perinatal and postnatal infant section for fetal distress. Chelmow et al.3 showed a relationship be- morbidity, and hence greater resuscitative needs. In this retrospective tween a prolonged latent phase in labor and the need for cesarean study, the infants with antenatal findings consistent with fetal distress section and newborn resuscitation. had significantly greater resuscitative needs. However, a significant The advent of fetal monitoring has contributed to an increase in number of the infants without the findings of fetal distress also had the diagnosis of fetal distress.4–8 However, determining which fetus is some resuscitative needs. The lack of statistical and clinical signifi- at greater risk for requiring resuscitation is only partially answered by cance between groups on the circulation resuscitation subscore may the monitoring technique. The level of expertise of the personnel be attributed to the fact that neither group had a significant number performing the monitoring and how the information is being inter- of neonates requiring much or any circulatory resuscitation. The preted are other considerations. Several studies have shown that less difference between the means on the NICU admission subscores was experience and less expertise may result in a falsely elevated incidence also not statistically or clinically significant, because there were a of fetal distress.9,10 Further, once fetal distress is suspected based on substantial number of neonates in both groups who were admitted to monitoring, it is more likely that a cesarean delivery will be per- the NICU for various reasons not related to resuscitative needs. formed expediently, because the time factors involved with the actual Confounding factors in this retrospective study were that the delivery of the neonate also affect perinatal outcome.11,12 housestaff (both obstetric and pediatric/neonatal) were involved in A great part of the literature on fetal distress has focused on the the decision-making process at all levels, that the housestaff changed risk of perinatal morbidity and mortality as it relates to the presence services on a regular monthly basis, and that the resuscitation team of “positive” findings on perinatal monitoring and testing and the was not “blinded” to the reasons for cesarean delivery. This means

Journal of Perinatology 2000; 2:101–104 103 Posen et al. Fetal Monitoring and Resuscitative Needs

that there was little ability to control for standardization in the judg- Subscore category Points Category ment of fetal distress, in the assignment of Apgar scores, in the assess- given subscore ment of true need for a variety of perinatal/neonatal interventions, C. Circulation score (circle all that apply) and in the assessment of need for admission to the NICU. For exam- None needed 0 ple, a less-experienced obstetric house officer might have over-read a Umbilical venous catheter placement or fluid 3 fetal strip as fetal distress, or a less-experienced pediatric house officer, resuscitation upon knowing that a cesarean section was being performed for fetal Cardiac medications (epinephrine, atropine) 4 distress, might have assigned a lower and less objective Apgar score Cardiac compressions 5 while prophylactically administering unnecessary supplemental oxy- Total circulation subscore (sum of circled values) — gen. Because the information in this retrospective study was taken D. NICU admission subscore from a computer analog database derived from the information en- Not admitted 0 tered on the original delivery records, there was no ability to control Admitted 3 — for differences in judgment and clinical decision-making. These factors and the results of this study suggest the need to further assess Total resuscitation score (AϩBϩCϩD) — this problem on a prospective basis. In this hospital, pediatric housestaff continue to attend all full-term cesarean deliveries, regardless of whether they are routine or performed for fetal distress indicators. References 1. Jacob J, Pfenninger J. Cesarean deliveries: when is a pediatrician necessary? Ob- CONCLUSION stet Gynecol 1997;89:217–20. 2. Ng PC, Wong MY, Nelson EA. Paediatrician attendance at caesarean sections. Eur In the group of neonates studied, those with antepartum/intrapartum J Pediatr 1995;154:672–5. monitoring that suggested fetal distress had a clinically and statisti- 3. Chelmow D, Kilpatrick SJ, Laros RK Jr. Maternal and neonatal outcomes after cally greater need for resuscitative intervention at delivery, indicating prolonged latent phase. Obstet Gynecol 1993;81:486–91. appropriateness of pediatrician attendance. Although infants without an antenatal determination of fetal distress appeared to have had 4. Stafford RS. Recent trends in cesarean section use in California. West J Med 1990;153:511–4. significantly less resuscitative needs in general, there was still a clinically significant number of these infants who required at least some 5. Vintzileos AM, Antsaklis A, Varvarigos I, Papas C, Sofatzis I, Montgomery JT. A form of intervention. At our teaching hospital, all cesarean deliveries randomized trial of intrapartum electronic fetal heart rate monitoring versus intermittent auscultation. Obstet Gynecol 1993;81:899–907. are still attended by pediatric housestaff. This study suggests the need for a prospective blinded study of resuscitative needs and outcomes of 6. Vintzileos AM, Nochimson DJ, Guzman ER, Knuppel RA, Lake M, Schifrin BS. infants with and without fetal distress as determined by antenatal Intrapartum electronic fetal heart rate monitoring versus auscultation: a meta- analysis. Obstet Gynecol 1995;85:149–55. monitoring and delivered by cesarean section. 7. Sarno AP Jr, Phelan JP, Ahn MO. Relationship of early intrapartum fetal heart rate patterns to subsequent patterns and fetal outcome. J Reprod Med 1990;35: Appendix A: Resuscitation Scoring 239–42. Subscore category Points Category 8. Arduini D, Rizzo G, Soliani A, Romanini C. Doppler velocimetry versus nonstress given subscore test in the antepartum monitoring of low-risk pregnancies. J Ultrasound Med A. Inverted Apgar score (10 minus Apgar score) 1991;10:331–5. 1 minute — 9. Lidegaard O, Bottcher LM, Weber T. Description, evaluation, and clinical deci- 5 minutes — sion-making according to various fetal heart rate patterns. Acta Obstet Gynecol Total inverted Apgar subscore (average of minute — Scand 1992;71:48–53. 1 and 5 scores) 10. Baruffi G, Strobino DM, Paine LL. Investigation of institutional differences in B. Ventilation score (circle all that apply) primary cesarean birth rates. J Nurse Midwifery 1990;35:274–81. None needed 0 11. Roemer VM, Heger-Romermann G. What factors modify the conditions of the Blow-by O 1 2 newborn infant in emergency cesarean section? [in German] Z Geburtshilfe Narcan administered 2 Perinatol 1992;196:141–51. Bag-and-mask positive pressure ventilation given 3 Thick meconium present or below cords 3 12. Saili A, Sarna MS, Haldar D, Kumari S, Dutta AK. Delayed cesarean section: neo- Intubation for meconium 4 natal outcome. Indian Pediatr 1990;27:601–4. Intubation for poor effort or distress 5 13. Nageotte MP, Towers CV, Asrat T, Freeman RK. The value of a negative antepar- Chest tube placement 6 tum test: contraction stress test and modified biophysical profile. Obstet Gynecol Total ventilation subscore (sum of circled values) — 1994;84:231–4.

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