Phenylephrine Clinical Trial
Official title:
The Effect of Preoperative Anxiety on Phenylephrine Dosage During Cesarean Delivery Under Spinal Anesthesia, A Prospective Observational Study.
Spinal anesthesia is considered gold standard anesthetic technique of choice for cesarean
delivery (1). However its use is frequently associated with maternal hypotension, which
occurs in up to 71% of cases, without prophylactic treatment(2) Spinal hypotension can lead
to unpleasant maternal side effects such as nausea, vomiting and dizziness. In addition,
adverse effects on the neonate occur because of reduced uteroplacental blood flow resulting
in impaired fetal oxygenation and fetal acidosis. As such, current research recommends the
prophylactic use of vasopressors for improved maternal and fetal outcomes(3).
The international consensus statement on the management of hypotension during cesarean
delivery states, that a prophylactic phenylephrine infusion is superior to bolus
administration and should be dose titrated according to blood pressure parameters (4). In
according to the international guidelines, in our obstetric anesthesia unit, we use a
standardized spinal anesthetic regime protocol with a standardized prophylactic phenylephrine
infusion at a rate of 50 mcg/min, with the vasopressor dose titrated according to every
minute blood pressure parameters.
Spinal anesthesia causes maternal hypotension, resulting from a blockade of sympathetic
efferent neurons. Patients with higher baseline sympathetic activation have been known to
have more marked hypotension after spinal anesthesia (5, 6) Anxiety causes generalized
sympathetic activation (7). In a previous research the investigators showed that preoperative
anxiety assessed by VAS had a significant effect on hypotension after spinal anesthesia (8).
Study objective:
In this study the investigators aim to evaluate the effect of anxiety on the cumulative
phenylephrine dosage in women undergoing cesarean delivery under spinal anesthesia with
prophylactic phenylephrine infusion. The primary hypothesis is that parturients who suffer
from preoperative anxiety measured by a verbal numerical scale (VNS) anxiety score and
Spielberger State-Trait Inventory questionnaire, will receive higher cumulative doses of
phenylephrine (resulting from higher incidence of maternal hypotension).
Methods:
This is a prospective, observational, single center study, which will be conducted at the
Rabin Medical Center (Beilinson campus), Petach Tikva, Israel, a tertiary university
hospital. This study Is a purely observational study, with no implication on the medical
treatment provided.
Two hundred women aged 18 and above undergoing cesarean section delivery under spinal
anesthesia will be enrolled after filling out an informed consent prior to surgery. Women
will be requested to fill out an informed consent in the women's surgery waiting room on the
day of surgery, when they aren't under any pain.
The parturients preoperative anxiety will be assessed in the women's waiting room, on the day
of the surgery using two previously validated direct psychological measures of anxiety:
verbal numerical scale (VNS) anxiety score (9, 10), and the Spielberger. State-Trait
Inventory questionnaire (13).
Women will also be asked about nausea and vomiting during the surgery and in the post
anesthesia care unit.
In according to standard departmental clinical practice, baseline blood pressure will be
determined in the preoperative holding area by recording 3 times ≥ 3 minutes apart using an
automated oscillometric blood pressure cuff on the arm with the patient supine with left
uterine displacement, with the mean of the 3 values taken as a baseline systolic and
diastolic blood pressure. Women will undergo spinal anesthesia and blood pressure will be
measured evert minute during labor. Hypotension will be treated by titrating the
phenylephrine infusion and by phenylephrine boluses, using a standardized algorithm according
to departmental protocol. At the time of spinal injection, a phenylephrine infusion will be
started at 50 mcg/min. The automated blood pressure cuff will be programmed to cycle each
minute. When each new blood pressure result will appear, the phenylephrine infusion will be
adjusted based on the systolic blood pressure by a standard algorithm.
Parturient's obstetric history, obstetric data and anesthetic data will be collected from
each of the participant's medical file, in an anonymized way.
;
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT04419662 -
Evaluation of Patients After Cardiac Surgery: Novel Ultrasound Parameters for Quantification of Renal Perfusion & Analysis of Phenylephrines' Effect on Invasive Haemodynamics and Echocardiographic Measures
|
Phase 4 |