Clinical trial NCT06741410: Ephedrine Versus Phenylephrine for Spinal Block - Related Hypotension in Cesarean Delivery
Official title: The Effect of Prophylactic Phenylephrine Infusion and Interventional Ephedrine Boluses on Umbilical Blood pH in Women Undergoing Cesarean Delivery Under Spinal Anesthesia: a Retrospective Case - Control Study
Study type: OBSERVATIONAL
Overall status: ACTIVE_NOT_RECRUITING
Conditions: Spinal Anesthesia
Cesarean Delivery
Neonatal Acidosis
Keywords: cesarean delivery
spinal anesthesia
phenylephrine
ephedrine
hypotension
Lead sponsor: Centre of Postgraduate Medical Education
Sponsor class: OTHER
First posted: 2024-12-19
Enrollment: 80
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Initial cohort of patients will consist of selected cases of cesarean deliveries from Orlowski Hospital in years 2020 - 2022, Department of Obstetrics and Gynaecology, Warsaw, Poland.

Intention is to include 40 cases in each group.

Brief summary: The study is designed to compare two strategies used in the management of hypotension caused by spinal anesthesia for cesarean section: intravenous phenylephrine given as prophylactic infusion and interventional boluses of intravenous ephedrine. Phenylephrine is currently recommended for battling spinal anesthesia - related sympathectomy, due to some scientific data on possible negative effects of ephedrine on fetal wellbeing. Therefore this study will retrospectively compare both clinical and laboratory data of the newborns delivered by cesarean section where either large dose of ephedrine or continuous infusion of phenylephrine was used for management of hypotension

Detailed description: Single - shot spinal block is a gold standard of anesthesia for cesarean delivery. It has been proven to decrease maternal morbidity and improve neonatal outcomes. Despite being most frequently used type of anesthesia in obstetrics, spinal block - related complications remain frequent in term parturients, of which hypotension is of utmost importance. Two widely accepted medications used in its prevention and treatment are phenylephrine and ephedrine, of which continuous, preventive phenylephrine infusion is considered superior in terms of neonatal safety.

Although there is some scientific evidence towards ephedrine having negative effect on neonatal acid - base status, it is still the most popular vasoconstrictor used for management of perioperative hypotension in Poland. It is an indirect adrenergic agonist, acting through release of noradrenaline from peripheral nerve endings. Beta - receptors mediated adrenergic stimulation of neonatal tissues is thought to be responsible for endocrine abnormalities, acid - base disturbances and possibly worse Apgar scores. Phenylephrine on the other hand is a direct and selective alpha-1 agonist and is regarded to exert very little or even no neonatal effects. Maternal complications related to phenylephrine infusion is hypertension and reflex bradycardia.

As convincing evidence is still lacking, this study is designed to retrospectively compare neonatal outcomes and perioperative hemodynamic data of mothers where either infusion of phenylephrine or boluses of ephedrine were used to control spinal -related hypotension during cesarean section.

Eligibility criteria: Inclusion Criteria:

* Cesarean delivery at term under spinal anesthesia
* American Society of Anesthesiologists (ASA) physical status \<3
* BMI \<40
* Preemptive phenylephrine infusion or ephedrine boluses used during surgical procedure

Exclusion Criteria:

* No vasoconstrictor (phenylephrine nor ephedrine) used throughout the procedure
* Total dose of ephedrine less than 15mg
* poor quality of anesthetic record - data required for analysis not available

Primary outcomes:
measure: Umbilical blood pH
timeFrame: During delivery (from spinal injection to umbilical clamping and cutting)
measure: Umbilical blood Base Excess (BE)
timeFrame: During delivery (from spinal injection to umbilical clamping and cutting)
Secondary outcomes:
measure: Hemodynamic stability
timeFrame: During delivery (from spinal injection to umbilical clamping and cutting)
Other outcomes:
Locations:
city: Warsaw
country: Poland
facility: Centre of Postgraduate Medical Education,Department of Anesthesia and Intensive Care
Study officials:
affiliation: Department of Anesthesia and Intensive Care, Orlowski Hospital, Warsaw
name: Małgorzata Malec-Milewska, MD, Prof.
role: STUDY_CHAIR
References:
citation: Ngan Kee WD, Khaw KS, Tan PE, Ng FF, Karmakar MK. Placental transfer and fetal metabolic effects of phenylephrine and ephedrine during spinal anesthesia for cesarean delivery. Anesthesiology. 2009 Sep;111(3):506-12. doi: 10.1097/ALN.0b013e3181b160a3.
citation: Higgins N, Fitzgerald PC, van Dyk D, Dyer RA, Rodriguez N, McCarthy RJ, Wong CA. The Effect of Prophylactic Phenylephrine and Ephedrine Infusions on Umbilical Artery Blood pH in Women With Preeclampsia Undergoing Cesarean Delivery With Spinal Anesthesia: A Randomized, Double-Blind Trial. Anesth Analg. 2018 Jun;126(6):1999-2006. doi: 10.1213/ANE.0000000000002524.
citation: Mohta M, Aggarwal M, Sethi AK, Harisinghani P, Guleria K. Randomized double-blind comparison of ephedrine and phenylephrine for management of post-spinal hypotension in potential fetal compromise. Int J Obstet Anesth. 2016 Aug;27:32-40. doi: 10.1016/j.ijoa.2016.02.004. Epub 2016 Feb 21.