EFFECT OF MATERNAL HYPERURICEMIA ON POST-SPINAL HYPOTENSION AND UTERINE TONE IN
NORMOTENSIVE PARTURIENTS UNDERGOING NON-ELECTIVE CESAREAN DELIVERY: A PROSPECTIVE
OBSERVATIONAL STUDY
Background
Uric acid (UA) is considered a marker of oxidative stress, that has also been implicated in labor. Further,
during pregnancy, oxidative stress and ROS have been shown to cause impaired relaxation of vascular
smooth muscles and significantly impaired contractility of the myometrium. Given these associations,
we hypothesize that serum uric acid levels may increase during labor with a decrease in incidence of
post-spinal hypotension and impairment of uterine contractility in laboring women undergoing non
elective cesarean deliveries.
Aims
To observe the effects of hyperuricaemia on incidence of post spinal hypotension, use of supplemental
uterotonics, intraoperative blood loss and short term neonatal outcome.
Methods
Following ethics committee approval and written informed consent, this prospective observational
study was conducted in laboring women with singleton pregnancy and normal blood pressure
undergoing non elective cesarean delivery.
Samples for uric acid estimation at admission to labor room and prior to shifting for cesarean delivery
were obtained. LSCS was carried out under SAB using 10mg of 0.5% hyperbaric bupivacaine with 15µg
fentanyl. Before delivery of the baby our target was to keep SBP >100 mmHg or to prevent a fall of more
than 20% in the MAP using IV Phenylephrine 50 µg boluses. Episodes of hypotension and total dose of
vasopressor given upto the time of uterine incision was recorded. Following expulsion of placenta,
uterine tone and contractility was recorded every 2 minutes for 10 minutes and graded as satisfactory
(score >7) or unsatisfactory(score ≤7). In cases of unsatisfactory uterine tone use of other uterotonics as
well as any other measures taken to manage uterine atony (like uterine massage) was recorded.
Intraoperative blood loss was estimated using modified Gross formula. Neonatal outcome was
evaluated by noting the Apgar scores and analyzing cord blood for presence of acidosis.
Results There was a significant decrease in the incidence of post-spinal hypotension in parturients with
increased uric acid levels. Vasopressor use was also significantly decreased in these patients.
Conclusion Elevated serum uric acid levels in parturients undergoing cesarean delivery with neuraxial
anaesthesia correlated with decreased incidence of post-spinal hypotension