How should we interpret lactate in labour? A reference study. (8th August 2022)

• Record Type: Journal Article
• Authors: Dockree, Samuel; O'Sullivan, Joseph; Shine, Brian; James, Tim; Vatish, Manu
• Is Part Of: BJOG. Volume 129:Number 13(2022)
• Page Start: 2150
• Page End: 2156
• Publication Date: 2022-08-08
• Subjects: infection -- labour -- lactate -- perinatal -- puerperium -- sepsis; Obstetrics -- Periodicals; Gynecology -- Periodicals; 618
• DOI: 10.1111/1471-0528.17264
• Languages: English
• ISSNs: 1470-0328

Abstract

Abstract: Objective: To investigate maternal lactate concentrations in labour and the puerperium. Design: Reference study. Setting: Tertiary obstetric unit. Population: 1279 pregnant women with good perinatal outcomes at term. Methods: Electronic patient records were searched for women who had lactate measured on the day of delivery or in the following 24 hours, but who were subsequently found to have a very low likelihood of sepsis, based on their outcomes. Main outcome measures: The normative distribution of lactate and C‐reactive protein (CRP), differences according to the mode of birth, and the proportion of results above the commonly used cut‐offs (≥2 and ≥4 mmol/l). Results: Lactate varied between 0.4–5.4 mmol/l (median 1.8 mmol/l, interquartile range [IQR] 1.3–2.5). It was higher in women who had vaginal deliveries than caesarean sections (median 1.9 vs. 1.6 mmol/l, p diff < 0.001), demonstrating the association with labour (particularly active pushing in the second stage). In contrast, CRP was more elevated in women who had caesarean sections (median 71.8 mg/l) than those who had vaginal deliveries (33.4 mg/l, p diff < 0.001). In total, 40.8% had a lactate ≥2 mmol/l, but 95.3% were <4 mmol/l. Conclusions: Lactate in labour and the puerperium is commonly elevated above the levels expected in healthy pregnant or non‐pregnant women. There is a paucity of evidence to support using lactate or CRP to make decisions about antibiotics around the time of delivery but, as lactate is rarely higher than 4 mmol/l, this upper limit may still represent a useful severity marker for the investigation and management of sepsis in labour.