Shock Index Values During the Peripartum Period in Patients Under
Neuraxial Labour Analgesia: a Multicentre Prospective Cohort Study
Abstract
Objective: We aimed to assess the association between intrapartum
neuraxial labour analgesia (NLA) and shock index values during the
peripartum period. Design: A multicentre prospective cohort study.
Setting: Two reference centres in Colombia. Population: Obstetric
patients in labour with term gestations were divided according to
whether they underwent NLA between 2017 and July 2018. Methods: We
collected maternal blood pressure and heart rate within the first and
second stages of labour and every 30 minutes up to two hours postpartum.
We assessed the association between intrapartum NLA and shock index
values in a multivariable longitudinal mixed-effect model, adjusting for
covariates. Main outcome measures: Shock index changes over time during
labour and postpartum periods. Results: We included 522 patients, 228
(43.7%) with NLA and 294 (56.3%) without NLA. Except in the first
stage of labour [0.68 (IQR, 0.63-0.74) vs 0.73 (IQR, 0.64-0.82);
p=0.07], the shock index values were significantly higher in patients
with NLA during the second stage of labour and postpartum (all p values
<0.001). In the longitudinal mixed-effect model analysis,
shock index values were higher in the NLA group. After adjusting the
multilevel model by age, nulliparity, and cervical dilation, the mean
shock index without NLA across the measurements was 0.69, while in NLA
was 0.76 (mean difference of 0.067). Conclusions: In patients receiving
NLA, the shock index values during labour differ from those during the
postpartum period. Thus, under these conditions, the shock index should
be interpreted differently. Keywords: Shock Index; Neuraxial Labour
Analgesia; Postpartum Haemorrhage.