Gürkan M. Arikan

Low fetal oxygen saturation at birth and acidosis.

Objective To measure umbilical cord blood oxygen saturation, to calculate preductal oxygen saturation at birth, and to assess its predictive value for acidosis. Methods Umbilical cord blood samples of 1537 live-born singleton neonates were analyzed. Oxygen saturation was measured by spectrophotometry; pH and base excess were measured by a pH and blood gas analyzer. Preductal oxygen saturation was calculated with an empirical equation. Acidosis was defined as 2 standard deviations (SDs) below the mean of umbilical artery (UA) pH or base excess (7.09 and −10.50 mmol/L, respectively). The predictive value for acidosis of UA and umbilical vein (UV) oxygen saturation and calculated preductal oxygen saturation was determined with receiver operating characteristic curves. Results The mean values (±SD) of UV, UA, and calculated preductal oxygen saturation were 52 ± 18%, 26 ± 17%, and 31 ± 16%, respectively. Forty-seven neonates had UA pH less than 7.09 and 60 had UA base excess less than −10.50 mmol/L. The UV, UA, and calculated preductal oxygen saturation showed considerably weaker relations to UA base excess (multiple r2 = .056, .003, and .017, respectively; P < .001) than to UA pH (multiple r2 = .112, .126, and .148, respectively; P < .001). Receiver operating characteristic areas under the curve were higher when predicting low pH compared with low base excess (for UV, UA, and calculated preductal oxygen saturation: 0.716 versus 0.699, 0.747 versus 0.586, and 0.765 versus 0.628, respectively). The difference was significant for UA oxygen saturation (P < .05). All tests showed high sensitivity and negative predictive values, but low specificity and positive predictive values. Conclusion Low fetal oxygen saturation measured at birth seemed to be associated with low fetal pH and base excess values, but its predictive value for acidosis in an unselected population was limited, particularly if acidosis was metabolic.

Fetal pulse oximetry and visual on-line signal identification in the second stage of labor

OBJECTIVE To determine the accuracy of reflection pulse oximetry and visual on-line signal identification during the second stage of labor. STUDY DESIGN The reflection pulse oximetry system used allows visual on-line identification of valid signals by showing the original red and infrared signals. With this system oxygen saturation measurements are averaged over nine heartbeats only. An atraumatic suction probe was used. The measurements of the last 10 minutes before delivery were compared with umbilical venous cord blood samples taken soon after delivery. RESULTS The correlation between reflection pulse oximetry readings during the last 10 minutes before delivery and umbilical vein oxygen saturation was significant (r = 0.45; p < 0.0005). Standard regression analysis showed R2 of 0.45. This did not change if weighted by the rate of valid signals (R2 = 0.42). If the predelivery loss of valid signals was less than 5 minutes, the correlation improved (r = 0.47, p < 0.001). Umbilical vein pH did not correlate with pulse oximetry readings. CONCLUSION The reflection pulse oximetry system used allows visual on-line identification of even short periods of valid signals and reflects actual oxygen saturation in fetal arterial blood.

Course of Maternal Serum Magnesium Levels in Low-Risk Gestations and in Preterm Labor and Delivery

Objectives: To describe the course of total and ionized magnesium and total calcium levels in maternal serum during low-risk pregnancies and to compare women who developed preterm labor and delivery with those who delivered at term. Methods: 209 women with low-risk pregnancies were enrolled in a prospective trial before the 18th week of gestation. No woman received oral magnesium supplementation. The ionized and total magnesium and total calcium levels in maternal serum were measured every 4–6 weeks. The data were grouped into 3 gestational periods (≤18, 19–27 and ≥28 weeks of gestation) for overall comparison and analyzed with the general linear model for repeated measurements and ANOVA. p values of < 0.05 were considered statistically significant. Results: 145 gestations were available for analysis. 27 women were hospitalized for preterm labor and in 16 of these preterm delivery occurred. Ionized and total magnesium and calcium levels were significantly lower after the 18th week of gestation than before. The cation levels in women with preterm labor and delivery did not differ from those with term delivery. Conclusion: Ionized and total magnesium and calcium levels decrease with increasing gestational age. Preterm labor and delivery do not seem to be related to changes in serum cation levels.

Reproductive outcome after laparoscopic instillation of hyperosmolar glucose into unruptured tubal pregnancies

OBJECTIVE To determine intrauterine and ectopic pregnancy rates after local instillation of 50% glucose into unruptured tubal pregnancies. DESIGN Retrospective cohort of 183 patients, who were observed for 16 to 108 months (median, 64 months). SETTING University hospital. PATIENT(S) One hundred eighty-three women who underwent laparoscopic instillation of hyperosmolar glucose for unruptured tubal pregnancies. INTERVENTION(S) Completion of questionnaires. MAIN OUTCOME MEASURE(S) Pregnancy rate, tubal recurrence rate. RESULT(S) A total of 124 women returned the questionnaire and had a desire for spontaneous conception. The conception rate and the intrauterine pregnancy rate were 79% and 73%, respectively. Seventy percent of all women with desire for spontaneous conception had live births. The rate of subsequent ectopic pregnancies was 12%. Tubal patency of the treated tube was demonstrated in 69% of 39 women at hysterosalpingography. CONCLUSION(S) The long-term prognosis for conception after laparoscopic instillation of hyperosmolar glucose for unruptured tubal pregnancy is favorable and comparable to that of other conservative treatments.

Contents Vol. 14, 1999

313 14th International Congress ‘The Fetus as a Patient’ New York City, N.Y., USA, April 22–24, 1999 285 Erratum 321 Drs. Haackert Prize 1999 Awarded to Prof. Juri Wladimiroff, The Netherlands Brezinka, Ch. (Innsbruck) 323 Prenatal Orogastric Gene Delivery Results in Transduction of the Small Bowel in the Fetal Rabbit Wu, Y.; Liu, J.; Woo, S.; Finegold, M.J.; Brandt, M.L. (Houston, Tex.) 328 Hemangioma of the Umbilical Cord: Stenotic Change of the Umbilical Vessels Kamitomo, M.; Sueyoshi, K.; Matsukita, S.; Matsuda, Y.; Hatae, M. (Kagoshima); Ikenoue, T. (Miyazaki) 332 Course of Maternal Serum Magnesium Levels in Low-Risk Gestations and in Preterm Labor and Delivery Arikan, G.M.; Panzitt, T.; Gücer, F.; Scholz, H.S.; Reinisch, S.; Haas, J.; Weiss, P.A.M. (Graz) 337 Failure of Amniotic Septostomy in the Management of 3 Subsequent Cases of Severe Previable Twin-Twin Transfusion Syndrome Pistorius, L.R. (Johannesburg/Pretoria); Howarth, G.R. (Pretoria) 341 Serum Enzyme Activities in Premature Infants with Bronchopulmonary Dysplasia Zanardo, V. (Padua); Rizzo, L. (Livorno); Trevisanuto, D.; Simbi, K.A.; Golin, R.; Magarotto, M.; Marzari, F. (Padua) 345 Significance of Echogenic Foci in the Left Ventricle of the Fetal Heart in a Low-Risk Population Jaffe, R. (New York, N.Y.); Cherot, E.; Allen, T.; Glantz, J.Ch. (Rochester, N.Y.) 348 Are Bilateral Fetal Lung Masses Double Trouble? Lipshutz, G.S.; Lopoo, J.B.; Jennings, R.W.; Farrell, J.; Harrison, M.R.; Albanese, C.T. (San Francisco, Calif.) 351 Amniotic Band Syndrome in Triplet Pregnancy Suzuki, S.; Yoneyama, Y.; Sawa, R.; Sinagawa, T.; Hayashi, T.; Araki, T. (Tokyo) 354 Continuous Observation of Nitric Oxide Production in the Fetal Rat Brain during Uteroplacental Ischemia Asakura, H.; Nakai, A.; Yokota, A.; Sekiguchi, A.; Koshino, T.; Araki, T. (Tokyo) 360 Multifetal Pregnancy Reduction and Selective Termination: The Canadian Experience von Dadelszen, P.; Johnson, J.-A.M. (Toronto); Farquharson, D.F.; Wilson, R.D. (Vancouver); Seaward, P.G.R. (Toronto) 365 Cerebellar Hypoplasia: Could It Be a Sonographic Finding of Abnormal Fetal Karyotype in Early Pregnancy? Rosati, P.; Guariglia, L. (Rome) 368 Initiating Extradural Analgesia during Labour: Comparison of Three Different Bupivacaine Concentrations Used as the Loading Dose Harms, C.; Siegemund, M.; Marsch, S.C.U.; Surbek, D.V.; Hösli, I.; Schneider, M.C. (Basel) 375 Abstracts 7th Journées Parisiennes Obstétrico-Pédiatriques, February 5, 1999 378 Erratum 379 Author Index Vol. 14, 1999 381 Subject Index Vol. 14, 1999 No. 5 No. 6