Preanesthetic withdrawal improves the conversion efficacy of prolonged epidural labor analgesia to epidural surgical anesthesia: a prospective cohort study combined with MRI mechanistic exploration.
Interrupting epidural labor analgesia before surgery associated with lower epidural anesthesia failure rates
Preanesthetic withdrawal improves the conversion efficacy of prolonged epidural labor analgesia to epidural surgical anesthesia: a prospective cohort study combined with MRI mechanistic exploration.
Conversion from epidural labor analgesia (epidural labor analgesia) to epidural surgical anesthesia (epidural surgical anesthesia) is a common clinical procedure in obstetric practice.
This study aimed to evaluate the impact of preanesthetic epidural labor analgesia interruption on the conversion efficacy of prolonged epidural labor analgesia (≥ 8 h) to epidural surgical anesthesia and to explore underlying anatomical and physiological mechanisms using lumbar magnetic resonance imaging (magnetic resonance imaging).
This integrated study comprised two complementary components: a prospective cohort study and a controlled before-after magnetic resonance imaging study.
interrupting the epidural before surgery nearly halved anesthesia failure
Multivariable logistic regression adjusted for maternal weight and epidural labor analgesia duration confirmed that longer epidural labor analgesia interruption time was independently associated with reduced odds of epidural surgical anesthesia failure (OR = 0.986, 95% CI 0.977-0.996, P = 0.006).
The magnetic resonance imaging study revealed that at 2 h post-delivery, compared with 24 h post-delivery, the dural sac area was significantly reduced and the epidural space area was significantly enlarged at all lumbar levels.
Epidural fluid accumulation was observed in 18.2% of parturients at 2 h.
Preanesthetic interruption of epidural labor analgesia for ≥ 30 min significantly improves the conversion efficacy of prolonged epidural labor analgesia to epidural surgical anesthesia, as shown by reduced failure rates, enhanced anesthesia quality, and improved maternal outcomes.
Mechanistically, epidural labor analgesia-related epidural space dilation, dural sac compression, and residual low-concentration local anesthetics (possibly associated with epidural fluid accumulation) may contribute to conversion failure, and these adverse changes can be relieved by preanesthetic epidural labor analgesia interruption.