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Obstetrica şi Ginecologia

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Obstetrica şi Ginecologia

IN MEMORIAM DR. EMIL GHEORGHIŢĂ

Obstetrica şi Ginecologia

Opinii şi recomandări curente pentru utilizarea meşei în chirurgia ginecologică – review al literaturii

Introduction

Preeclampsia (PE) is one of the leading causes of maternal and fetal mortality and morbidity around the world. The first trimester is the preferred gestational interval for PE screening⁽¹⁾.

The study of Doppler ultrasound flow of maternal uterine arteries in pregnancy provides a useful tool for evaluating the physiology of the maternal-fetal unit⁽²⁾. The relationship between abnormal uterine artery Doppler flow and several complications of pregnancy is well established⁽³⁾.

An increased risk of maternal and fetal complications has been reported in women showing an increased resistance to the blood flow in the uterine arteries during pregnancy⁽⁴⁾. Pregnancies which result in normal term deliveries show increased diastolic blood flow velocity and loss of the early diastolic notch by 22 weeks of gestation⁽⁵⁾.

Doppler velocimetry of the uterine arteries during the first trimester of gestation and its relationship with preeclampsia prediction have been intensely studied⁽⁶⁾.

First- and second-trimester uterine artery Doppler blood flow assessments have been shown to have a high predictive value for clinical outcome, with a rather wide range of specificity and sensitivity values for pregnancy complications⁽⁷⁾.

Reference ranges for uterine artery Doppler ultrasound indices are recommended to be used during pregnancy screening⁽⁸⁾. The pulsatility index (PI) was significantly higher in both trimesters when using transvaginal ultrasound^(9-12).

For a correct uterine artery Doppler indices measurement, the gestational age of the patient must be between 11 weeks + 0 days and 13 weeks + 6 days. In case of trans­abdominal route for ultrasound, a midsagittal section of the uterus and cervical canal should be obtained, the internal cervical os is identified and the transducer should be tilted from side to side in each paracervical region by color flow mapping, in order to identify the uterine arteries^(13,14). The sampling gate of the pulsed wave Doppler must be set at 2 mm to cover the whole vessel and the angle of insonation must be less than 30°; blood flow velocity waveforms from the ascending branch of the uterine artery at the closest possible point to the internal os; the PI is to be measured after obtaining at least three similar consecutive waveforms and the mean PI of the arteries is calculated^(13,14).
 

Materials and method

Uterine artery Doppler flow indices were assessed, in a prospective study, on 305 pregnant patients with singleton pregnancies who eventually gave birth vaginally or by caesarean section within the 11 weeks + 0 days and 13 weeks + 6 days gestational ages in our clinic during the 2014-2018 period (as both inpatients and outpatients) by using a Sonoscape SSI-6000 (China) and a General Electric Logiq e (USA) ultrasound devices.

The Doppler flow was analyzed with a 2-mm window and an insonation angle of less than 30 degrees, according to existing guidelines.

The ultrasound results and demographics were recorded and statistically assessed using Microsoft Excel and MedCalc.

Sensitivity, specificity, positive and negative predictive values and odds ratios of bilateral, unilateral and total uterine artery notching for hypertensive pregnancy complications were calculated.

Results

A number of 21 patients in our study group had hypertensive pregnancy complications, which are detailed in Table 1. The demographics of the study group and the statistical significance of the differences between the patients with normal outcome and with hypertensive complications are presented in Table 2. Tables 3, 4 and 5 reveal the sensitivity, specificity, the positive and negative predictive values and odds ratios of PI, RI and PI/RI above the 95^th percentile for hypertensive pregnancy complications (RI: resistivity index; GH: gestational hypertension; HTN: hypertension; OR: odds ratio).

Discussion and conclusions

The highest detection rates and positive predictive values were offered by using any type of notching (bilateral and unilateral). The RI revealed the highest specificity, positive and negative predictive value, and odds ratios.

The overall detection rates ranged from 0% to 33.33%, the RI having the highest values.

Positive predictive values were low (0-13.33%), the usefulness of the screening residing in the very high negative predictive values, in addition to the sensitivity.

The main weakness of our study was the relatively low number of patients.

Conflict of interests: The authors declare no conflict of interests.