Search

Two children aged 1 and 20 months developed alveolar hypoventilation syndrome. They suffered severe apnoeic episodes and periodically required assisted ventilation. Their ventilatory response to carbon dioxide was lower than that of normal children and the transcutaneous oxygen tension during sleep was well below the normal range. Treatment with medroxyprogesterone acetate resulted in an improved response to carbon dioxide, and assisted ventilation was no longer needed. Oxygen and carbon dioxide tensions improved but were still slightly abnormal during sleep. There were no clinical side effects of treatment but one infant had slight pituitary suppression. [ABSTRACT FROM AUTHOR]

Copyright of Archiv für Gynäkologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A 23-year-old primigravida underwent induced abortion in the 17th week of pregnancy because ultrasound fetometry had indicated possible encephalocele/hygroma of the skull and deformities of limbs and abdominal wall. The fetus delivered showed a deep facial cleft, absence of nose and maxilla, absence of parietal and frontal bones, missing right upper extremity, and a large thoracoabdominal defect with herniation of internal organs. The placenta was large, with an amniotic fold across the fetal surface. The brain was holoprosencephalic with a midline monoventricle and with focal brain wall dysplasia. The right orbit and eye were absent. The left eye was microphthalmic, with an abnormal cornea, a large choroidal coloboma inferiorly, a dysplastic retina, and a cataractous spherical lens. Theories discussed are pathogenesis of the limb-body wall complex (LBWC) and ocular malformations, particularly uveal coloboma. Previous cases of anophthalmos and uveal coloboma are listed. Microscopic examination of the eye was performed in only one of these. The present case is the sixth case published of choroidal coloboma in association with the LBWC.

The transcutaneous Po2 monitoring technique was applied in 20 newborns. The method proved reliable during hypoxemia, normoxemia and hyperoxemia, with a high correlation between Ptco2 and Pao2 in simultaneously obtained arterial samples. Although Ptco2 reliably reflects changes in Pao2, occasional arterial samples are still required for establishing the relationship between Ptco2 and Pao2, especially in patients with impaired circulation. When this relationship has been determined, the therapist may rely on the recorded Ptco2 level for hours, given that the energy supply required to maintain the electrode at a preset temperature level remains constant. A considerable difference between Ptco2 and Pao2 or a change in the energy supply level to the electrode may alert the therapist to check the patient's circulatory status. The Ptco2 technique is now fully developed and can be recommended for use in neonatal intensive care.

The technique for transcutaneous oxygen (TcPO2) monitoring is now routine in neonatal intensive care. The method was presented earlier as a potential tool for fetal surveillance during labor. The current study reports on two techniques generally used for the application of the electrode to the fetus. The application of the electrode by a suction instrument does not influence the TcPO2 level recorded and the use of this technique is very simple. However, the main disadvantage of the suction instrument is that the electrode is easily detached. Application of the electrode by glue is technically a little more difficult but has the advantage of being much more efficient. If the criteria for a reliable recording presented in the study are fulfilled, the technique may be used as an additional parameter to diagnose true fetal hypoxemia.

Continuous transcutaneous oxygen (PtcO2) monitoring is a noninvasive technique for recording changes in central oxygenation. PtcO2 monitoring has been for some years a routine method in neonatal and adult intensive care. The technique is a potential tool in fetal surveillance during labor. Some recently published studies which have been critical of the use of PtcO2 monitoring in the delivery room reveal a lack of thorough understanding of the limitations of the technique. From the author's experience with the technique, it is obvious that, when the PtcO2 electrode is attached according to recommendations and when the monitoring situation fulfills certain criteria, PtcO2 reliably reflects changes in the fetal oxygenation during labor and may be used for the diagnosis of true hypoxemia. PtcO2 monitoring does not replace any other available routine monitoring for fetal surveillance, but when the technique is refined, it may become an additional means of diagnosing fetal jeopardy. As a research parameter, PtcO2 monitoring has already contributed to a more diversified understanding of the process of fetal asphyxia.

At application of the electrode for continuous transcutaneous oxygen monitoring, a superatmospheric pressure may be produced between the skin and the electrode membrane. Such a pressure may change the electrode characteristics resulting in a slower reacting electrode. A superatmospheric pressure may also influence on the subepidermal capillaries and on the oxygen diffusion through the skin. The results in the current in vitro study show that an increase of the pressure between the electrode membrane and the skin results in a slower reacting electrode, only when the pressure also produces an increased diffusion distance from the capillaries to the electrode membrane. Thus, the PtcO2 electrode seems rather rough and different PtcO2 levels recorded among patients or in the same patient at two applications are not produced by the application procedure per se but by physiological differences in the skin at the electrode application site.