Die Wertigkeit von Laktat im Rahmen des fetalen blood samplings

Abstract

Background: Salings technique of analyzing foetal scalp blood during delivery became a standard obstetric practice in monitoring neonates ever since its first use in 1962. It is an examination in which a small incision is made in the foetal scalp with a lancet and about 100l of blood is taken and analyzed by a micro blood sampler. It assesses foetal wellbeing by determining the current acid-base regulation. Usually pH and Base excess - levels are taken into account when deciding upon subsequent delivery procedures. The lactate level is also routinely determined but has never been considered a decision-making factor. High lactate levels are a sign of a metabolic acidosis and have as such been recorded in cases of hypoxic infants. In addition to a few publications reporting findings of high lactate level in cord blood sampling, a retrospective study has been made to detect the value of lactate in foetal scalp blood sampling. Objective: Aim of this study was to evaluate a lactate level that assures non-pathological foetal outcome. Method: In a retrospective study data of 1200 labours were screened. Finally 767 complete data sets of foetal scalp blood analysis were included in the analysis. Collection was performed at the Department of Obstetrics and Gynaecology, Medical University Graz during a period from 2004 to 2007. Lactate, pH and BE levels and the foetal outcome were compared to determine the significant value of lactate which predicts foetal wellbeing during delivery. The pH and lactate concentrations in these examinations were determined only in specific cases. Outcome variables were based on Apgar 1 score =< 7. Results: Scalp blood lactate concentration and pH were simultaneously obtained in order for these two laboratory values to be compared correctly. Significant indirect correlations were evident between pH and lactate values and also between lactate level and Apgar 1. In order to guarantee an Apgar 1 = > 7, a lactate level of no more than 4.2 mmol/l was determined. Conclusion: The lactate level in foetal scalp blood sampling is a significant indicator for foetal wellbeing and outcome. A lactate level of 4.2 mmol/l or greater is a clear indicator that the foetal wellbeing is non-satisfactory and a possible invention might be necessary.

Datum der Bewilligung	2011
Originalsprache	Englisch
Gradverleihende Hochschule	Medizinische Universität Graz
Betreuer/-in	Wolfgang Schöll (Betreuer*in)