Acid-base evaluation of umbilical cord blood: relation to delivery mode and Apgar scores.

Acid-base status of umbilical artery and vein blood was measured immediately after delivery in 300 cases. A slight acidosis of mixed respiratory/metabolic type was found in newborns delivered following a second stage of 10-30 min duration. After a second stage of more than 30 min the metabolic contribution to the acidosis was predominating. With Apgar scores lower than 10 the pH was found to decrease and carbon dioxide tension to increase. Induction or augmentation of labor by oxytocin did not influence the acid-base status of umbilical cord blood. Delivery by vacuum extraction or low forceps resulted in lower pH and higher carbon dioxide tension in umbilical cord blood, but the changes were associated with the indication for instrumental delivery and not with mode of delivery. A large arterio-venous difference between the acid-base parameters was usually connected to vigorous newborns and a small difference to depressed infants. The carbon dioxide tension was usually increased in newborns with decreased pH, and a close correlation between these parameter was found. No case of acidosis (pH below 7.15) was found in this population at carbon dioxide tensions below 7.2 kPa; at higher Pco2 values only 25% of the newborns were acidotic. A Pco2 level of 7.7 kPa might be used at transcutaneous carbon dioxide monitoring during labor, although the sensitivity and specificity of this parameter will have to be decided in a prospective study.

Continuous standard base excess monitoring during human labour.

Previously, the various components of fetal acid-base state during labour could only be estimated discontinuously by fetal blood sampling, or continuously by monitoring of a single component. This is the first report describing simultaneous continuous monitoring of the tissue pH, the transcutaneous carbon dioxide tension and on-line calculation of the tissue-standard base excess (t-SBE) of the human fetus during labour. In seven uncomplicated deliveries t-SBE was increasing or constant, thus indicating no fetal hypoxia. When a more reliable tissue pH electrode becomes available, t-SBE calculation may become a valuable tool in the management of high-risk labours.

Fetal carbon dioxide tension during human labour.

Fetal carbon dioxide tension during labour is elevated in both metabolic and respiratory acidosis, but intermittent fetal blood analyses often fail to detect PCO2 changes during acute complications. Transcutaneous carbon dioxide monitoring is continuous and the possibility of diagnosing PCO2 changes is therefore better. The theoretical background for transcutaneous measurements and methods for clinical monitoring are described. Close correlations with capillary and arterial blood values have been found, and the atraumatic principle with a simple electrode application indicates a promising new method for acid-base assessment during human labour.

Induction of labor by prostaglandin E2: intracervical gel or vaginal pessaries?

To investigate the best route of prostaglandin medication for induction of labor, 125 pregnant women with unfavorable cervices (Bishop scores less than or equal to 6) were randomized to induction of labor with either PGE2 (0.5 mg) in a viscous intracervical gel once daily or PGE2 pessaries (2.5 mg) 1-2 a day. As estimated by life table analysis, the pessaries were significantly more effective inducing vaginal delivery compared to intracervical gel (24 h: P less than 0.025, 48 h: P less than 0.01, logrank test) and vaginal delivery was obtained within 24 h/48 h in 50%/72% of the women in the pessary group and in 29%/55% of the women in the intracervical group. Cervical ripening was found within 3 h (P less than 0.001) and in the subsequent 3 to 24 h period (P less than 0.005) after both treatments, no difference being found between the groups. The pessaries were much more effective inducing regular contractions compared to the intracervical gel (P less than 0.005, logrank test), so the latter seems preferable if cervical ripening rather than induction is intended. No difference was found analyzing the active labor period. No difference was found in methods of delivery, neonatal parameters (Apgar scores, umbilical artery blood pH and standard base excess), and the patients' attitude towards both methods of induction were equally favorable.

Predictive value of pelvic scores for induction of labor by local PGE2.

The predictive value of pelvic scores, parity, age and gestational age for induction of labor by local prostaglandin-E2 (PGE2) was examined in 336 women attempting induction of labor by intracervical or vaginal PGE2. The patient characteristics were correlated to: (1) vaginal delivery within 48 h, (2) the period from induction to onset of labor (latency period), and (3) the duration of labor. The Bishop score (P < 0.01) and even more the Lange score (P < 0.0001) were significantly inversely correlated to both latency period and induction-delivery period. This was caused by cervical dilatation (P < 0.001), fetal station (P < 0.05) and cervical length (P < 0.05), whereas position and consistency of the cervix were of no importance. All three periods studied were significantly (P < 0.0001) shorter in parous women. In primiparous women, gestational age was of no importance for the latency period; however, higher gestational age was associated with longer labor (P < 0.001). We conclude that the predictive value of pelvic scores on induction hardly differs using local PGE2 compared to conventional methods; furthermore, the Bishop score should be substituted, disregarding position and consistency of the cervix, but putting more weight to cervical dilatation. A new pelvic score is proposed.

Induction of labour by balloon catheter with extra-amniotic saline infusion (BCEAS): a randomised comparison with PGE2 vaginal pessaries.

OBJECTIVE: A new method for induction of labour--balloon catheter with extra-amniotic saline infusion (BCEAS)--is evaluated in randomised comparison with prostaglandin E2 (PGE2) in vaginal pessaries. STUDY GROUP: One-hundred and nine pregnant women with unfavourable cervices. MAJOR OUTCOME MEASURES: The efficiency of inducing vaginal delivery and the level of 'disadvantages following induction of labour' (DisFIL scorings). RESULTS: Overall, BCEAS was less efficient inducing vaginal delivery than vaginal PGE2 (P < 0.01) because of a significant difference among parous women (P < 0.01). In the (larger) primiparous women group, and particularly in the subgroup of these having very low pelvic scores (Lange score, < or = 3), the efficiencies of the two methods were equal (P = 0.06) and P = 0.55, respectively). The levels of DisFIL scorings were not significantly different. However, higher rates of caesarean section followed BCEAS than PGE2 (29% and 10%, respectively; P < 0.05). Serious infectious complications were not recorded following BCEAS. No difference was apparent in the status of the neonates (judging from Apgar scores and umbilical artery pH and SBE). The women, delivering vaginally, commented the two methods equally favourably. CONCLUSION: BCEAS was less efficacious than vaginal PGE2 pessaries, though among primiparous women, especially those with very unfavourable cervices, the difference was not significant. Further refinements of the method are suggested.

Prediction of mode of delivery and 'DisFIL score' following induction of labor by local PGE2.

The objective of the study was to evaluate pre-induction risk factors for (i) assisted vaginal delivery (forceps or vacuum extraction), (ii) caesarean section, (iii) failed induction followed by caesarean section, and from these to evaluate a score of the 'Disadvantages Following Induction of Labour' (the DisFIL score). The study was a case-control study applied on a prospective cohort of 336 pregnant women induced by local PGE2. Assisted vaginal delivery was associated with primiparity (OR (odds ratio) = 10.7; CI, 3.6-32.0) and higher pelvic scores (Bishop score: OR = 1.9; CI, 1.4-2.6). Caesarean section was related to higher maternal age (P < 0.001) and lower pelvic scores (Bishop score: OR = 0.7; CI, 0.5-1.0, P < 0.05). When performed because of fetal distress, assisted vaginal delivery and caesarean section were both associated with lower fetal weights (P < 0.05). Failed induction followed by caesarean section was related to primiparity (P < 0.0001, Fisher's test) and lower pelvic scores (Bishop score: OR = 0.6; CI, 0.4-0.9). A higher 'DisFIL score' was associated with primiparity (OR = 4.7; CI, 2.8-8.0), higher maternal age (P < 0.01), lower pelvic scores (P < 0.01, chi 2 test) and PGE2 in intracervical gel rather than in vaginal pessaries (OR = 2.1; CI, 1.4-3.2). It is concluded that the major predictors of 'Disadvantages Following Induction of Labor' by local PGE2 are primiparity, high maternal age, low pelvic scores and the method of.

Fetal and maternal transcutaneous PCO2 levels during labour and the influence of epidural analgesia.

The Departments of Obstetrics and Gynaecology of the Hvidovre University of Copenhagen and the Free University of Amsterdam collaborated in a study on the relationship of maternal and fetal acid-base state in the intrapartum period. Transcutaneous PCO2 levels of mother (tcPCO2m) and fetus (tcPCO2f) were continuously recorded in 52 patients during labour. TcPCO2f and tcPCO2m correlated significantly (r = 0.42, P < 0.002). During the first stage of labour, a rather stable level was found for tcPCO2f (7.7 +/- 1.6 kPa) and tcPCO2m (4.4 +/- 0.8 kPa). TcPCO2m decreased significantly to 3.8 +/- 0.7 kPa (P < 0.01) in the hour before full cervical dilatation, probably due to maternal hyperventilation as a reaction to painful uterine contractions. TcPCO2f likewise showed a tendency to a decrease to a mean value of 7.4 +/- 1.5 kPa. In eight cases epidural analgesia was applied because of painful uterine contractions. Prior to the epidural analgesia, tcPCO2m (3.8 +/- 0.8 kPa) and tcPCO2f (6.7 +/- 1.7 KPa) were significantly lower in this subgroup compared to the total population. After pain relief by application of epidural analgesia, tcPCO2m and tcPCO2f returned to the population mean.

Fetal transcutaneous PCO2 measurements during labour.

The departments of Obstetrics and Gynaecology of the Universities of Bonn and Copenhagen and the Free University of Amsterdam cooperated in the European Community Concerted Action Project 'New methods for Perinatal Surveillance'. In 95 patients fetal transcutaneous PCO2 (tcPCO2) recording (measuring temperature 41 degrees C) during labour was evaluated regarding its clinical applicability. During the first stage of labour fetal tcPCO2 was rather stable at a level of 7.3 +/- 1.4 kPa. In the second stage there were marked differences between the three subpopulations. In the first stage of labour the correlation between tcPCO2 and PCO2 in fetal blood samples was 0.38 (P = 0.02) and in the second stage -0.20 (P = 0.36). The correlation of fetal tcPCO2 with umbilical artery PCO2 was 0.30 (P = 0.01) and with pH -0.30 (P = 0.01). Using a fetal tcPCO2 level of 8.0 kPa as a cut-off point to predict an umbilical artery pH less then 7.20, sensitivity was 88%, specificity 65%, positive predictive value 29% and negative predictive value 97%. The likelihood ratio of a positive test was 2.47 and of a negative test 0.13. It is concluded that fetal tcPCO2 possibly can be an additional tool to exclude fetal acidosis. In case of values above 8.0 kPa further evaluation of the fetal acid-base balance is indicated.

Evaluation of a needle pH electrode for continuous tissue-pH monitoring during labor. Characteristics during acidosis in the rat.

A prototype of a needle tissue-pH (t-pH) electrode designed for continuous t-pH monitoring of the human fetus during labor is described and evaluated in vitro and in vivo in the rat. Respiratory acidosis was induced by ventilation with 5% carbon dioxide, and t-pH measured by the needle electrode compared to simultaneous t-pH measured by the Kontron-Roche electrode and to arterial blood pH. A close correlation between the two t-pH electrodes was demonstrated (r = 0.80, P < 0.001). Furthermore, a close correlation was found between t-pH and arterial blood pH during the first 15 min of acidosis (r = 0.82, P< 0.001). It is concluded that the needle electrode fulfils nearly all theoretical demands to a t-pH electrode for clinical use.

[Metrorrhagia after sterilization]. / Metroragi efter sterilisation.

PIP: The frequency of hemorrhagic disturbance was calculated retrospectively among 207 sterilized women prior to and after sterilization. Significantly more women experienced metrorrhagia requiring curettage in the 7-year period after sterilization than during the 7-year period prior to it. 75 patients who were sterilized between the ages of 27-30 years were compared with nonsterilized women of the same age bracket. 6 years poststerilization significantly more women who had been sterilized had undergone curettage due to hemorrhagic disturbances than among the nonsterilized women. 15.5% of the women had hysterectomy during the observation period, almost 1/2 of which were due to these disturbances. (author's modified)^ieng

[T/QRS-ratio and cardiotocographic changes in the second stage of labor--related to fetal condition at delivery]. / T/QRS-ratio og kardiotokografiforandringer i andet stadium af fødslen--relateret til fostrets tilstand ved fødslen.

The T/QRS ratio of the foetal electrocardiogram (ECG) was recorded from 92 women in labour. Recordings to within 30 min of delivery from 55 women were available for analysis. There was a weak but statistically significant correlation between increasing mean T/QRS ratio and increasing pH/standard base excess (SBE) in the umbilical artery of the 55 foetuses (Spearman, respectively r = 0.28, p = 0.04 and r = 0.29, p = 0.04); the corresponding numbers for the subgroup of 22 where the cardiotocogram was classified as normal being respectively r = 0.51, p = 0.02 and r = 0.61, p = 0.003. The mean T/QRS ratio of foetuses born with an umbilical artery pH of > 7.15 was 0.12 (range -0.05-0.32). There was no significant difference in mean T/QRS ratio between foetuses born with an umbilical artery pH < 7.16 (n = 10) and those born with a pH > 7.15. No trend in T/QRS ratio was found as labour progressed. There were only three cases of metabolic acidose (SBE = -10.3 to -10.6 mmol/l and pH = 7.09-7.14. In two of the cases the CTG was abnormal and in one case intermediate; mean T/QRS ratio was normal in all three cases with metabolic acidosis. Abnormal CTG was able to predict an umbilical artery pH < 7.15 with a sensitivity of 67% and a positive predictive value of 27%. T/QRS ratio (T/QRS = -0.05-0.25: "normal") was not able to predict a low pH. The chance of finding significant changes in T/QRS ratio was limited by the small number of foetuses with clinically significant acidosis.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cardiotocographic monitoring of deliveries. A prospective comparative study of 2 types of electrodes]. / Kardiotokografisk fødselsovervågning. En prospektiv sammenlignende undersøgelse af to elektrodetyper.

The number of electrodes employed, the frequency of reapplication, the technical quality of monitoring and the complications of use of spiral electrodes and Copeland electrodes for cardiotocographic monitoring of deliveries are assessed in a prospective randomized investigation. The number of electrodes employed and the frequency of reapplications were significantly lower employing Copeland electrodes. Similarly, the electrode signal was significantly better as assessed by the percentage of the duration of monitoring in which the cardiotocogram did not register during the second stage of labour on account of poor electrode signals. No differences were found in the frequencies of complications or subjective discomfort in the mother on employing the two types of electrodes.