Different Approaches to Maternal Hypotension During Cesarean Section

Pregnancy Clinical Trial

Official title:

Pharmacological or Non-Pharmacological Management of Maternal Hypotension During Elective Cesarean Section Under Subarachnoid Anesthesia: a Randomized, Controlled Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00991627
• Other study ID #: ANEST-OST-02
• Status: Completed
• Phase: Phase 4
• First received: October 7, 2009
• Last updated: August 26, 2010
• Start date: September 2009
• Est. completion date: August 2010

Study information

• Verified date: August 2010
• Source: University of Parma
• Contact: n/a
• Is FDA regulated: No
• Health authority: Italy: Ethics CommitteeItaly: National Monitoring Centre for Clinical Trials - Ministry of HealthItaly: The Italian Medicines Agency
• Study type: Interventional

Clinical Trial Summary

The aim of this study is to compare two different therapeutic approaches to blood pressure reduction: pharmacological vs. non-pharmacological. The setting is that of patients undergoing scheduled Cesarean section under spinal anesthesia and suffering from aorta-caval compression syndrome, which causes a sudden drop in blood pressure.

Description:

The supine hypotensive syndrome of pregnancy is induced by compression of the inferior caval vein by the enlarged uterus. It occurs in approximately 8% of pregnant women at term. More patients may develop an asymptomatic variety of this syndrome in the supine position. The hypotensive effect of spinal anesthesia per se may thus be aggravated in a significant number of term parturients. A preoperative supine stress test (SST) before elective cesarean section under spinal anesthesia has been shown to predict severe systolic hypotension with reasonable accuracy.

Different strategies have been proposed for the management of this complication; they can be divided into pharmacological and non-pharmacological ones.

According to pharmacological strategies, vasoactive drugs are used to treat hypotension induced by sympathetic efferent blockade following spinal anesthesia. To this end, α-agonist ephedrine is commonly considered the best choice because of its minimal impact on the fetoplacental circulation. However, excessive use of ephedrine may be detrimental to neonatal well-being because of its vasoconstrictor effect on fetoplacental circulation.

Non-pharmacological treatments may represent a valuable, safer alternative. According to many authors non-pharmacological treatments aimed at removing the cause of aorta-caval compression syndrome are to be preferred because more appropriate from an etiopathogenetic point of view. The use of a wedge-shaped cushion placed under the right hip is a well-known non-pharmacological strategy which allows the uterine left lateral displacement and, consequently, the removing of the compression from the inferior vena cava.

The aim of the present study is to compare, through the evaluation of neonatal well-being, the efficacy of these approaches to hypotension after spinal anesthesia for elective Caesarean section in parturients affected by aorto-caval compression.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 36
• Est. completion date: August 2010
• Est. primary completion date: August 2010
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years to 50 Years

Eligibility

Inclusion Criteria:

• Patients undergoing spinal anesthesia for elective Cesarean section

• Patients in ASA Physical Status Class I or II

• Informed written consent to participation

• Positive Supine Stress Test

Exclusion Criteria:

• Any known fetal pathology

• Indication to general anesthesia

• Known allergy to any of the study drugs

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Anesthesia,Spinal
• Cesarean Section
• Hypotension
• Pregnancy

Intervention

Drug:
• Bupivacaine
10 mg of a 5 mg/ml hyperbaric solution, intrathecally
• Morphine
200 µg of a 100 µg/ml solution, intrathecally
• Lactated Ringer's solution
25 ml/min intravenously
• Ephedrine, continuous infusion
37.5 mg/h intravenously
• Ephedrine, bolus
6.25 mg IV bolus prn. Hypotension defined according to study protocol for each arm.
• Atropine
0.1 mg/kg iv bolus prn Bradycardia defined as 50% drop in heart rate from baseline values.

Locations

Country	Name	City	State
Italy	University and Hospital of Parma (Azienda Ospedaliero-Universitaria di Parma)	Parma	PR

Sponsors (2)

Lead Sponsor	Collaborator
University of Parma	Azienda Ospedaliero-Universitaria di Parma

Country where clinical trial is conducted

Italy, 

References & Publications (4)

Cyna AM, Andrew M, Emmett RS, Middleton P, Simmons SW. Techniques for preventing hypotension during spinal anaesthesia for caesarean section. Cochrane Database Syst Rev. 2006 Oct 18;(4):CD002251. Review. — View Citation

Helwig JT, Parer JT, Kilpatrick SJ, Laros RK Jr. Umbilical cord blood acid-base state: what is normal? Am J Obstet Gynecol. 1996 Jun;174(6):1807-12; discussion 1812-4. — View Citation

Kinsella SM, Lohmann G. Supine hypotensive syndrome. Obstet Gynecol. 1994 May;83(5 Pt 1):774-88. Review. — View Citation

Kinsella SM, Norris MC. Advance prediction of hypotension at cesarean delivery under spinal anesthesia. Int J Obstet Anesth. 1996 Jan;5(1):3-7. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Neonatal arterial base excess		<5 min from birth	Yes
Secondary	Neonatal arterial and venous pH, venous base excess		<5 min from birth	Yes
Secondary	Apgar score		1 and 5 minutes from birth	Yes
Secondary	Maternal serum levels of cardiac troponin (baseline, immediate postsurgery, 6 and 12 hours after surgery)		Baseline and up to 12 h postoperatively	Yes
Secondary	Incidence of maternal hypotension ( <20% baseline or mean arterial pressure <60 mmHg).		q5min from anesthesia to end of surgery	Yes
Secondary	Incidence of maternal bradycardia (heart rate <30% of baseline or <60 beats per minute)		q5min from anesthesia to end of surgery	Yes
Secondary	Peripheral arterial oxygen saturation: incidence of desaturation (SpO2 <92%) and mean values for each arm.		q5min from anesthesia to end of surgery	No
Secondary	Administered atropine		from anesthesia to end of surgery	Yes
Secondary	Amount of ephedrine administered (mg)		from anesthesia to end of surgery	Yes
Secondary	Time between induction of anesthesia and skin incision			No
Secondary	Time between skin incision and delivery			No