An analysis of risk factors associated with blood transfusion in ectopic pregnancy

Objective: To determine the risk factors associated with blood transfusion in ectopic pregnancy.Methods: A retrospective chart review of the presentation and hospital course of ectopic pregnancies managed over 5 years at two hospitals was undertaken. Thirty-two variables, including demographics, presenting signs and symptoms, and intraoperative findings, were examined in univariate and multivariate logistic modeling.Results: Among 185 patients with histologically confirmed ectopic pregnancies who were managed surgically, 8.6% or 16 women required transfusion. Multivariate analysis of risk factors for blood transfusion demonstrated a statistically significant association with 1) initial hemoglobin <10 g/dL (odds ratio [OR] 38.8, 95% confidence interval [CI] 6.0-356.8) and 2) hCG levels >/= 6500 mIU (OR 18.1, 95% CI 3.6-158.1), as well as 3) abnormal bleeding on presentation (OR 0.08, 95% CI 0.007-0.42. Presence of two of these factors has a sensitivity of 82% (95% CI 48-98%) and a positive predictive value of 33% (95% CI 16-54%). No case had all three factors present.Conclusion: This report is, to our knowledge, the first regression analysis of risk factors for transfusion associated with ectopic pregnancy. It demonstrates that initial hemoglobin and hCG levels as well as abnormal bleeding on presentation are independent risk factors for blood transfusion in ectopic pregnancy.

Amnioinfusion-induced malpresentation

Amnioinfusion is a valuable and common intrapartum procedure for the relief of cord compression and to dilute thick meconium. Like most procedures, it is not without risk and we report a case of malpresentation following amnioinfusion. Intrapartum fetal demise occurred after malpresentation during amnioinfusion resulting in a change of fetal presentation from vertex to unrecognized shoulder presentation. Further study is needed regarding changes in volume of amniotic fluid and saline as well as intrauterine manipulation and the effect on fetal presentation. Careful attention must be paid to infused volumes during amnioinfusion.

Management of pregnancies beyond forty-one weeks' gestation with an unfavorable cervix

OBJECTIVE

Our purpose was to determine the optimal management of pregnancies beyond 41 weeks' gestation with a cervix unfavorable for induction.

STUDY DESIGN

All uncomplicated pregnancies that reached 41 weeks' gestation with a Bishop score of < or = 4 were randomly assigned to one of three groups: (1) daily cervical examinations, (2) daily membrane stripping, or (3) daily placement of prostaglandin gel until 42 weeks.

RESULTS

In 105 pregnancies the Bishop score on admission to labor and delivery was significantly greater in the groups receiving prostaglandin or stripping of the membranes versus the control group, whereas the converse was time of gestational age at delivery (p = 0.0001). Fewer patients required induction in the two treatment groups (20%, 17%) versus the control (69%) patients (p < 0.0001).

CONCLUSIONS

Daily membrane stripping or daily placement of prostaglandin gel is successful in reducing the number of inductions at 42 weeks for postdatism.

Comparison of insulin regimens and administration modalities in pregnancy complicated by diabetes

PURPOSE

To compare insulin administration using premixed insulin (70% NPH/30% Regular) by an injectable pen with traditional self-mixed insulin administered by syringe.

METHODS

In this study, 93 women were enrolled into four groups: 1) self-mixed/syringe, 2) premixed/syringe, 3) self-mixed/pen, and 4) premixed/pen.

RESULTS

Women in the premixed pen group had significantly less cesarean deliveries for failure to progress in labor and a decrease (not significant) in postpartum infection and infant macrosomia. Patients felt premixed insulin administered by the pen was easier to use. No significant differences were noted in glucose control, compliance among the four groups, or cost.

CONCLUSION

Premixed insulin administration via the pen is safe, effective and no more costly than traditional treatment for pregnant diabetic women.

Ectopic pregnancy in sterilized and nonsterilized women. A comparison

OBJECTIVE

To assess whether differences occurred in the presentation, treatment and postoperative outcomes of ectopic pregnancy in sterilized and nonsterilized women.

STUDY DESIGN

All cases of ectopic pregnancy admitted over five years at two hospitals were reviewed. Using a case-control method, patients with ectopic pregnancy and prior tubal sterilization were compared with the next nonsterilized patient with ectopic pregnancy admitted within 30 days. Statistical comparison, utilizing t tests, chi 2 tests of Fisher's exact test, when appropriate, was performed.

RESULTS

Thirty-eight (18%) of 208 patients with ectopics during the study period had undergone prior sterilization. This group, when compared with the 38 nonsterilized patients with ectopics, was similar for gestational age at diagnosis, frequency of pelvic inflammatory and sexually transmitted diseases, and mean human chorionic gonadotropin (hCG) level; the preoperative sonographic findings were also similar in the two groups. Sterilized patients were less likely than controls to have had serial hCG levels, while their mean duration of symptoms at admission was shorter. Although both groups had a similar distribution of surgical management (laparoscopy, laparotomy or both) and postoperative complications, there were trends toward a higher risk of ectopic rupture and hemoperitoneum in sterilized patients.

CONCLUSION

Ectopic pregnancies following tubal sterilization have clinical manifestations and surgical outcomes similar to those occurring without prior sterilization, except for less frequent determination of serial hCGs, probably related to a shorter duration of reported preceding symptoms. The trend toward more frequent rupture and hemoperitoneum in this group suggests that sterilized patients are less likely to heed the early warnings of this complication.

Home blood pressure monitoring for pregnant patients with hypertension

OBJECTIVE

To determine whether automated measurement of blood pressure and pulse in a home setting can be easily accomplished by pregnant women with chronic hypertension.

STUDY DESIGN

In this prospective investigation, seven women with chronic hypertension complicating pregnancy recorded their blood pressure at home twice a day. These data were offloaded once daily into a computer at a remote site, and a computerized printout of these data was received by the physician.

RESULTS

The patients participated in the study for 12.2 +/- 5.8 weeks (range 4 to 18 weeks) and were between 23 and 42 weeks' gestation. Average mean arterial pressure in the home was 102 +/- 10 mm Hg, and average pulse was 81 +/- 11 beats per minute. In the clinic, the values were 112 +/- 13 mm Hg and 90 +/- 30 beats per minute (p < 0.05). Each patient was easily taught how to use the machine.

CONCLUSIONS

The home blood pressure monitoring device was easy to use and correlated well with values recorded by health professionals for this limited number of subjects. It was particularly helpful to patients (n = 5) who lived long distances (more than 60 miles) from the clinic and to women who needed adjustments of antihypertensive medication.

Do multiple measurements employing different ultrasonic techniques improve the accuracy of amniotic fluid volume assessment?

This investigation was undertaken to determine if the accuracy of the ultrasound assessment of abnormal amniotic fluid volume (oligohydramnios or polyhydramnios) is improved by employing multiple sonographic amniotic fluid measurements. Four ultrasound techniques consisting of the subjective assessment (ultrasonic visualization without measurement), largest vertical pocket, amniotic fluid index and 2-diameter pocket technique were performed followed by amniocentesis and dye-dilution confirmation of amniotic fluid volume in 66 singleton pregnancies. The ultrasound accuracy to detect abnormal amniotic fluid volume ranged from 61% with the largest vertical pocket to 70% with the 2-diameter pocket procedure used separately. Receiver operator characteristic curves demonstrated that combining the 4 ultrasonic measurements did not improve the accuracy of identifying amniotic fluid volumes.

Bishop score: a poor diagnostic test to predict failed induction versus vaginal delivery

BACKGROUND

We evaluated the accuracy of the Bishop score in predicting the likelihood of successful labor induction (entry into active phase) in nulliparous and multiparous women.

METHODS

During an index year, all patients having induction of labor and a preinduction Bishop score were included in a standard protocol for cervical ripening and use of oxytocin. Receiver-operating characteristic (ROC) curves were constructed for Bishop scores (0 to 11) to predict abdominal delivery for failed induction (final cervical dilation <4 cm) versus vaginal delivery.

RESULTS

Parturients who had vaginal delivery (n = 253) and those in whom attempted induction failed (n = 38) did not differ significantly with respect to maternal demographics, length of gestation, Bishop score and its distribution, and infant birth weight. The area under the ROC curve did not differ significantly from the area under the nondiagnostic line.

CONCLUSION

The Bishop score appears to be a poor predictor of the outcome of labor induction.

Comparison of insulin regimens and administration modalities in pregnancy complicated by diabetes

PURPOSE

To compare insulin administration using premixed insulin (70% NPH/30% Regular) by an injectable pen with traditional self-mixed insulin administered by syringe.

METHODS

In this study, 93 women were enrolled into four groups.: 1) self-mixed/syringe, 2) premixed/syringe, 3) self-mixed/pen, and 4) premixed/pen.

RESULTS

Women in the premixed pen group had significantly less cesarean deliveries for failure to progress in labor and a decrease (not significant) in postpartum infection and infant macrosomia. Patients felt premixed insulin administered by the pen was easier to use. No significant differences were noted in glucose control, compliance among the four groups, or cost.

CONCLUSION

Premixed insulin administration via the pen is safe, effective and no more costly than traditional treatment for pregnant diabetic women.

Limitations of clinical and sonographic estimates of birth weight: experience with 1034 parturients

OBJECTIVE

To compare the accuracy of clinical and sonographic estimates of fetal weight made throughout the third trimester of pregnancy.

METHODS

Patients in early labor had fetal weight estimated by two approaches: 1) clinical evaluation and palpation followed by 2) sonographic mensuration of fetal biparietal diameter, abdominal circumference, and femur length applied to Hadlock's formula. The accuracy of these two methods of estimating fetal weight was compared using Student t test, Wilcoxon test, and chi2 tests. P < .05 was considered significant. Prediction limits (50th, 90th, and 95th percentiles) were calculated for both techniques by obtaining the range of actual weights associated for a particular estimated fetal weight (EFW).

RESULTS

We enrolled 1034 parturients whose clinical EFWs yielded significantly higher mean (+/- standard deviation) simple error (48.2 +/- 411 g) and standardized absolute error (130 +/- 122 g/kg) than were obtained by use of sonographic formulas for EFW (-6.6 +/- 381 g and 104 +/- 89 g/kg, respectively). When the population was partitioned by gestational age, we found that sonographic EFW was more accurate than clinical EFW in preterm (n = 373) but not in term (n = 460) or post-term (n = 201) pregnancies. Prediction limits indicate that for a given EFW, for example, 800 g, the 90% ranges of actual weight based on clinical and sonographic EFW are 566-1829 g and 469-1667 g, respectively.

CONCLUSION

The apparent superiority of sonographic EFW over clinical EFW applies principally to preterm pregnancies. The prediction limitation calculation suggests that either method, for any particular estimate between 500 and 4500 g, has limited value in the estimation of actual birth weight, because this outcome is highly variable and frequently lies outside of the useful bandwidth (+/- 10%) for prospective management.

Mathematical models to correlate amniotic fluid index and amniotic fluid volume

PURPOSE

To describe a predictable relationship that relates amniotic fluid index (AFI) to amniotic fluid volume (AFV) and improve the accuracy of AFI to detect true oligohydramnios.

METHODS

Data from 42 parturients (group I) who underwent measurements of amniotic fluid sonographically (amniotic fluid index) as well as by dye-dilution technique was used to relate AFI to AFV. Subsequently, 22 consecutive women (group II) were used to test the accuracy of the equation to predict true oligohydramnios.

RESULTS

In group II, 11 of 22 patients had true oligohydramnios and the sensitivity, specificity, positive and negative predictive values of AFI < or = 5.0 to detect a confirmed AFV < 500 mL were 0%, 91%, 0%, and 48%, respectively. These values of AFI, when used in conjunction with the equation, improved to 73%, 55%, 62%, 67%, respectively. With AFI and the equation, significantly more patients in group II with true oligohydramnios (8 of 11) could be detected than with using AFI alone (0 of 11; p = 0.002).

CONCLUSION

AFI is poor predictor of true oligohydramnios. Using the mathematical model, the detection rate of oligohydramnios is significantly improved.

The accuracy of the summated amniotic fluid index in evaluating amniotic fluid volume in twin pregnancies

OBJECTIVE

Our purpose was to determine the accuracy of the summated amniotic fluid index designed to estimate the total amniotic fluid volume in twin pregnancies.

STUDY DESIGN

The summated amniotic fluid index was measured in 62 normal diamniotic twin pregnancies by adding the deepest vertical pockets in the four quadrants. Actual amniotic fluid volume was then determined in all 124 amniotic sacs by amniocentesis and a dye-dilution technique. For data analysis, amniotic fluid volumes were classified by percentile with use of previously reported norms.

RESULTS

There were significant differences in the percentile distribution of amniotic fluid volume as estimated by the summated amniotic fluid index and the actual volume as determined by dye dilution (p < 0.001). The summated amniotic fluid index has a sensitivity of only 13% in predicting amniotic sac volume.

CONCLUSION

The summated amniotic fluid index is a poor predictor of intertwin differences in amniotic fluid volume and cannot identify twin pairs at risk for oligohydramnios and hydramnios.

Amniotic fluid volume in normal singleton pregnancies

OBJECTIVE

To evaluate the amniotic fluid (AF) volume in normal singleton pregnancies from 15 to 40 weeks.

METHODS

This prospective study evaluated the AF volume in singleton pregnancies undergoing amniocentesis for genetic assessment of fetal karyotype, preterm labor, or fetal lung maturity. Amniotic fluid volume was determined using a dye dilution technique. To assess the relationship between AF volume and estimated gestational age, a nonlinear regression model was applied.

RESULTS

One hundred forty-four normal singleton pregnancies had AF volume evaluated. There was wide variability in the measured AF volumes with a significant (P < .01) increase in AF volume as a function of gestational age. Growth curve modeling estimated that AF volume continued to increase until 40 weeks' gestation. Analyses of the observed AF volume indicated that AF volume nearly doubled after 30 weeks' gestation.

CONCLUSION

In contrast to other reports indicating that maximal AF volume in singleton gestations is expected early in the third trimester, we observed the attainment of maximal AF volume near term.

Ultrasonographic assessment of amniotic fluid does not reflect actual amniotic fluid volume

OBJECTIVE

Our objective was to compare the ability of two methods of amniotic fluid assessment (two-diameter amniotic fluid pocket versus the amniotic fluid index) to predict oligohydramnios (actual amniotic fluid volume < 500 ml) or polyhydramnios (actual amniotic fluid volume > 1500 ml).

STUDY DESIGN

The amniotic fluid index and the two-diameter amniotic fluid pocket were assessed before amniocentesis and determination of amniotic fluid volume with the dye (aminohippurate sodium)-dilution technique. To assess the detection of either oligohydramnios or polyhydramnios, the areas under the receiver-operator characteristic curves (+/-SE) were estimated by the point-to-point trapezoidal method of integration. Prediction limits were calculated by regression analysis of amniotic fluid index or two-diameter amniotic fluid pocket versus actual amniotic fluid volume and determination of 95th percentile ranges for amniotic fluid volume.

RESULTS

We studied 144 patients with a mean (+/-SD) gestational age of 31.7 +/- 5.5 weeks; mean (+/-SD) amniotic fluid index and two-diameter amniotic fluid pocket were 12.6 +/- 6.1 cm and 21.2 +/- 18.4 cm2, respectively. Mean (+/-SD) actual amniotic fluid volume was 722 +/- 735 ml (range 101 to 4318 ml). The areas under the four receiver-operator characteristic curves were not significantly different from the nondiagnostic line (p < 0.05). Regression slopes (r values) for amniotic fluid index and two-diameter amniotic fluid pocket versus actual amniotic fluid volume were 0.34 and 0.23, respectively. Calculation of the prediction limit for 95% confidence that oligohydramnios is absent requires that the amniotic fluid index be 30 cm and the two-dimension amniotic fluid pocket be 90 cm2, both thresholds of which are currently considered to represent clinical polyhdramnios.

CONCLUSIONS

Both amniotic fluid index and two-dimension amniotic fluid pocket appear to be inaccurate predictors of actual oligohydramnios or polyhydramnios when compared with dye-dilution calculations of actual amniotic fluid volume.

Effect of green tea (Camellia sinensis) extract on the rat diaphragm

The effect of hot water extract of green tea on skeletal muscle and its neurotransmission was studied employing innervated and denervated rat diaphragm. Green tea extract (GTE) has a facilitatory effect at lower concentrations and a paralytic effect at higher concentrations on skeletomotor function. GTE did not have any effect on direct twitch responses or on acetylcholine (ACh) and KCl induced contractures of denervated rat diaphragm and it antagonised the submaximal paralytic effect of D-tubocurarine and decamethonium. GTE-induced facilitation and inhibition were nullified in the presence of magnesium chloride. Nifedipine, reduced GTE-induced facilitation as well as inhibition of twitch responses as a function of its concentration. It was suggested that GTE might act on Ca2+ channels at the skeletomotor junction. The effect of crude polyphenol on neuromuscular junctions was found to be similar to that of GTE. Therefore, it is suggested that the crude polyphenol content of GTE was the active constituent responsible for its effect on neuromuscular junction.

Intrapartum oligohydramnios does not predict adverse peripartum outcome among high-risk parturients

OBJECTIVE

Oligohydramnios can be defined by an amniotic fluid index < 5th percentile for gestational age or an amniotic fluid index < or = 5.0 cm regardless of gestational age. The purpose of this prospective study was to determine whether oligohydramnios by either definition predicts accurately, in a high-risk population, the risks for cesarean section for fetal distress, Apgar score < 7 at 5 minutes, and neonatal acidosis.

STUDY DESIGN

An amniotic fluid index was obtained in 490 consecutive parturients with medical or obstetric complications and a reliable gestational age. After each delivery, an umbilical arterial blood gas analysis was obtained. Both measures of amniotic fluid index were rated as screening tests with use of sensitivity, specificity, predictive values, and receiver-operator characteristic curves.

RESULTS

The incidences of cesarean section for fetal distress and umbilical arterial pH < 7.00 were 14% and 1.8%, respectively. The 70 neonates delivered by cesarean section for distress, compared with the 420 without, had a significantly higher incidence of pH < 7.00 (8.5% vs 0.7%, p = 0.0004, relative risk 5.0, 95% confidence interval 2.9 to 8.4). Sensitivity and positive predictive values of an amniotic fluid index < 5th percentile for gestational age to predict pH < 7.00 were 0.8% and 22%, respectively, and for an amniotic fluid index < or = 5.0 cm, 0.5% and 11%, respectively. Receiver-operator characteristic curves indicate that an amniotic fluid index between 0 and 20 cm cannot predict accurately which parturients will have cesarean sections for distress or be delivered of a newborn with a low Apgar score at 5 minutes or a pH < 7.10.

CONCLUSION

Both criteria for oligohydramnios are poor predictors of adverse outcome for high-risk intrapartum patients.

The accuracy of ultrasound evaluation of amniotic fluid volume in singleton pregnancies: the effect of operator experience and ultrasound interpretative technique

The objective of this study was to evaluate the effect of operator experience and ultrasound interpretation technique on the accuracy of ultrasound estimates of amniotic fluid volume. Ultrasound evaluation was carried out by an obstetric resident, a nurse sonographer, a maternal-fetal medicine fellow, and a maternal-fetal medicine staff member to subjectively estimate (visual interpretation without sonographic measurements) amniotic fluid volume in 63 pregnancies. Amniotic fluid volume was also evaluated using ultrasound measurements based on the largest vertical pocket technique, the amniotic fluid index, and the two-diameter pocket method. The accuracy of these ultrasound estimates was assessed by comparing the ultrasound results to actual amniotic fluid volume as determined by a dye-dilution technique. For analysis, amniotic fluid volumes were classified as oligohydramnios, normal, or hydramnios using established volumetric criteria for singleton pregnancies. Subjective estimates ranged from 65% to 70% correct and did not differ by operator experience except for the more accurate diagnosis of hydramnios by the maternal-fetal medicine staff. The three sonographic measurements were similar in overall accuracy (59-67%). The two-diameter pocket method was, however, significantly more accurate in identifying oligohydramnios. It appears that neither operator experience nor sonographic technique greatly affects the accuracy of ultrasound estimates of amniotic fluid volume.

Cesarean section for suspected fetal distress. Does the decision-incision time make a difference?

OBJECTIVE

To compare perinatal outcomes in patients at term (37 weeks) in whom the decision-incision time for cesarean delivery was due to suspected fetal distress.

STUDY DESIGN

All parturients who underwent cesarean delivery primarily for possible fetal distress during a three-year period were identified retrospectively. Student's t test and the chi 2 test were utilized, and P < .05 was considered significant. A regression analysis of decision-incision time and umbilical arterial pH was performed.

RESULTS

From 1991 to 1993, 1.3% (117/9,137) of term laboring patients underwent emergency cesarean delivery for the primary indication of possible fetal distress. In 61 patients (52%) the decision-incision time was 30 minutes, while it exceeded 30 minutes in the remaining 56 women. The two patient groups were similar in maternal demographics, antepartum complications, oxytocin usage, thick meconium, type of abnormal fetal heart rate tracing prompting surgery, use of amnioinfusion (41% vs. 36%), general anesthesia (97% vs. 93%), mean birth weight and Apgar score < 7 at five minutes. Three adverse outcomes were observed more frequently in association with decision-incision time > 30 minutes: (1) lower mean (+/-SD) umbilical arterial pH (7.16 +/- 0.15 vs. 7.26 +/- 0.06, P = .001), (2) pH < 7.00 (8/61 vs. 0/56, P = .005), and (3) admission to the neonatal intensive care unit (P = .008). When the incision was made longer than 30 minutes after the decision, there was no apparent adverse neonatal or infant outcome.

CONCLUSION

Although a cesarean decision-incision time < or = 30 minutes is a desirable goal for the fetus possibly in distress, failure to achieve this goal is not associated with a measurable negative impact on newborn outcome.

Cesarean section for suspected fetal distress. Does the decision-incision time make a difference?

OBJECTIVE

To compare perinatal outcomes in patients at term (37 weeks) in whom the decision-incision time for cesarean delivery was due to suspected fetal distress.

STUDY DESIGN

All parturients who underwent cesarean delivery primarily for possible fetal distress during a three-year period were identified retrospectively. Student's t test and the chi 2 test were utilized, and P < .05 was considered significant. A regression analysis of decision-incision time and umbilical arterial pH was performed.

RESULTS

From 1991 to 1993, 1.3% (117/9,137) of term laboring patients underwent emergency cesarean delivery for the primary indication of possible fetal distress. In 61 patients (52%) the decision-incision time was 30 minutes, while it exceeded 30 minutes in the remaining 56 women. The two patient groups were similar in maternal demographics, antepartum complications, oxytocin usage, thick meconium, type of abnormal fetal heart rate tracing prompting surgery, use of amnioinfusion (41% vs. 36%), general anesthesia (97% vs. 93%), mean birth weight and Apgar score < 7 at five minutes. Three adverse outcomes were observed more frequently in association with decision-incision time > 30 minutes: (1) lower mean (+/-SD) umbilical arterial pH (7.16 +/- 0.15 vs. 7.26 +/- 0.06, P = .001), (2) pH < 7.00 (8/61 vs. 0/56, P = .005), and (3) admission to the neonatal intensive care unit (P = .008). When the incision was made longer than 30 minutes after the decision, there was no apparent adverse neonatal or infant outcome.

CONCLUSION

Although a cesarean decision-incision time < or = 30 minutes is a desirable goal for the fetus possibly in distress, failure to achieve this goal is not associated with a measurable negative impact on newborn outcome.

Intrapartum amniotic fluid index and two-diameter pocket are poor predictors of adverse neonatal outcome

OBJECTIVE

The objective of this study was to determine whether amniotic fluid index < or = 5.0 cm or two-diameter pocket volume < or = 15 cm2 is a predictor of abdominal delivery because of fetal distress or of Apgar score < 7 at 1 or 5 minutes.

STUDY DESIGN

The study was prospective and involved 209 parturients in early labor who had ultrasonographic assessment of amniotic fluid volume by both methods.

RESULTS

The incidences of cesarean delivery because of fetal distress and of Apgar scores < 7 at 1 and 5 minutes were 8.1%, 9.0%, and 1.9%, respectively. Only Apgar scores < 7 at 1 minute were significantly higher among patients with a two-diameter pocket < 15 cm2 (16/114) as compared with > 15(2) (3/95, p = 0.007). Oligohydramnios by either method was a poor predictor of adverse outcomes (p values ranging from 0.06 to 0.21). Receiver-operating characteristic curves generated for the amniotic fluid index or two-diameter pocket to predict abdominal delivery because of fetal distress or Apgar scores < 7 at 1 minute indicate that both methods are poor diagnostic tests to predict these complications.

CONCLUSION

Intrapartum assessment of amniotic fluid volume, by amniotic fluid index or the two-diameter pocket technique, is a poor predictor of adverse neonatal outcome.

Sonographic examination does not predict twin growth discordance accurately

OBJECTIVE

To assess the accuracy of estimating birth weight among twins with discordancy (intra-pair difference in actual birth weight of more than 25%) and to determine the relative accuracy of an intra-pair difference in abdominal circumference (delta AC) of 20 mm or more or in estimated fetal weight (delta EFW) of 25% or more for the identification of discordant growth in twins.

METHODS

Over a 6-year period, we identified all non-anomalous twin pairs with gestational ages greater than 23 weeks and sonographic examinations within 3 weeks of birth. Ultrasonographic biometry of both twins included AC, head circumference, and femur length; these indices were used to estimate fetal weight by Hadlock's formula. Likelihood ratios, receiver-operating characteristic curves, and prediction limits were applied to assess the accuracy of the two diagnostic methods to predict an abnormal outcome.

RESULTS

A total of 242 twin pairs were studied. The mean gestational age among the 21 twins with abnormal growth (30.6 +/- 4.6 weeks) was significantly less than among the 221 twins with normal growth (33.2 +/- 4.0 weeks) (P < .005). The biometric measurements of fetal parts, sonographic estimate of fetal weight, and actual birth weight for both fetuses were significantly less for discordant twin pairs (P < .05). The accuracy of predicting birth weight, as determined by mean error and percentage of the estimate within 10% of the actual weight, was similar between the groups. Receiver-operating characteristic curves showed that both diagnostic tests yielded areas under the two curves not significantly different from the area under the nondiagnostic line (P > .05). Most important, prediction limit calculations indicated that a 90% certainty that the actual birth weight discordance was at least 25% was achievable only if delta AC was 172 mm or greater or delta EFW was 112% or more.

CONCLUSION

The most popular current methods (difference in AC or EFW) for predicting discordant growth in twin gestations have limited accuracy when held to a standard for discordance that requires a birth weight difference of at least 25%.

Cortical deafness following head injury -a case report

Cortical deafness is a rare entity. Only few case reports are available. In this paper, a case of right fronto-temporal contusion following head injury causing bilateral cortical deafness has been reported. Most of the cases reported in the past were because of cerebral infarcts due to arterial occlusion.

Remote umbilical arterial blood pH analysis: accuracy, utility, and limitations

It is not always possible or feasible to perform routine umbilical artery blood sampling at birth. This study was undertaken to assess the accuracy of selective remote umbilical arterial blood analysis to retrospectively predict the original birth pH of any newborn. Umbilical arterial blood samples were obtained in two preheparinized syringes immediately following 1007 deliveries. One sample was analyzed within 60 minutes of delivery. The other was placed on ice and later analyzed at variable time intervals up to 180 hours postpartum. The results of each remote analysis were adjusted using a previously published regression equation to accurately identify which newborns had pH values < 7.00, < or = 7.10, or < 7.20 at birth. Among the 1007 newborns, there were 14 (1.3%), 44 (4.3%), and 187 (18.5%) who had pH values < 7.00, < or = 7.10, and < 7.20, respectively, at birth. Remote umbilical arterial samples analyzed within 72 hours of delivery correctly identified newborns with an original pH < 7.00, < or = 7.10, or < 7.20 with: (1) a sensitivity of 100, 82, and 84%, respectively; (2) positive predictive values of 100, 93, and 66%, respectively; and (3) a test efficiency of 100, 99, and 89%, respectively. Up to 72 hours after delivery, remote umbilical arterial blood pH analysis can be reliably used to accurately identify the newborn that was acidotic at birth.

Intrapartum amniotic fluid index. A poor diagnostic test for adverse perinatal outcome

OBJECTIVE

To determine if an intrapartum amniotic fluid index (IAFI) < or = 5.0 cm, or any other level, is associated with abdominal delivery for fetal intolerance to labor or Apgar scores < 7 at one and five minutes.

STUDY DESIGN

Prospectively IAFI was obtained in the latent phase of labor in 1,000 parturients at > 26 weeks. Receiver operating characteristic curves were utilized to determine if any IAFI could be utilized to predict adverse outcome among (1) the entire population, (2) complicated pregnancies, (3) uncomplicated pregnancies, (4) term, or (5) preterm gestation.

RESULTS

The frequencies of abdominal delivery for suspected fetal intolerance and low Apgar scores were similar among patients with IAFI < or = 5.0 cm (n = 288) versus those with IAFI > 5.0 cm. All five receiver operating characteristic curves indicated that IAFI is a poor predictor of adverse outcomes. At all the discriminatory IAFIs (0-20 cm), the false positive rate was virtually identical to the true positive rate.

CONCLUSION

IAFI appears to be a poor screening test for identifying those at risk for abdominal delivery for presumed fetal distress or for birth of an infant with low Apgar scores.