Lactate Values During Labour and Their Correlation With Maternal and Foetal Outcome

Lactate Values During Labour and Their Correlation With Maternal and Foetal Outcome: a Prospective Observational Single-centre Study

Postpartum haemorrhage (PPH) represents a significant cause of morbidity in the obstetric population, with a mortality rate of 140,000 women per year, and the predominant cause of PPH (70%) is uterine atony.

Consequently, elevated lactate levels during labour could influence maternal and foetal well-being. We decided to assess lactate concentrations during labour in women receiving neuraxial anaesthesia and evaluate the association between high lactate levels and adverse maternal and foetal outcomes.

The secondary aims of the study were to assess lactate levels at different stages of labour and investigate whether increased lactate concentrations could influence neonatal cord pH upon delivery.

We conducted a prospective observational single-centre study involving women in active labour receiving neuraxial anaesthesia.

Labour analgesia was placed at the beginning of active labour, whose definition follows the NICE guidelines. The labour analgesia technique consisted of standard epidural puncture or dural puncture epidural; the maintenance of analgesia was through clinician intermittent boluses given on maternal request.

Lactate levels were assessed via a venous blood gas test utilising an IV cannula already placed in the woman's limb upon admission.

These measurements were taken at three different time points, as follows: T0: at the time of diagnosis of the active phase of the first stage of labour, T1: at the beginning of the active phase of the second stage of labour, at the beginning of active pushing, and T2: at the time of the delivery, before placenta expulsion.

Postpartum haemorrhage (PPH) has been defined following the definition of the Royal College of Obstetricians and Gynaecologists as a total blood loss ≥ 500 ml.

To measure umbilical cord pH, 1-2 ml of cord blood were taken from the umbilical artery one minute after birth, regardless of clamping.

Inclusion Criteria:

• ≥ 18 years old
• single pregnancy with a gestational age of ≥ 36 weeks
• active labour with a cervix dilation of 4 to 6 cm
• neuraxial analgesia
• consent to the study Exclusion criteria
• < 18 years
• twin pregnancy
• gestational age < 36 weeks,
• labour without labour analgesia
• cervix dilation > 6 cm at the moment of the placement of neuraxial analgesia
• not consent to the study