Phenylephrine and Noradrenaline for Post Spinal Anesthesia Hypotension

Kasr El Aini Hospital

Status and phase: Completed; Phase 2

Conditions: Adverse Anesthesia Outcome

Treatments: Drug: Bupivacaine; Drug: Norepinephrine; Drug: Placebo (normal saline); Drug: phenylephrine; Drug: Fentanyl

Study type: Interventional

Funder types: Other

Identifiers

NCT03015857

cesarean sections

Details and patient eligibility

About

Hypotension following spinal anesthesia for cesarean section is a serious problem. In this study we investigated the effect of the vasopressors phenylephrine and noradrenaline on postspinal hypotension.

Full description

On arrival to the operating room, an 18g cannula will be inserted and monitors will be applied (electrocardiography - pulse oximetry - non-invasive blood pressure monitor). Patients will receive spinal anesthesia with 500 ml rapid crystalloid co-load. Ten milligrams heavy bupivacaine in addition to 20 mcg fentanyl will be injected in L3-L4 or L4-L5 interspace using 25 g spinal needle in the sitting position.

After spinal block, patients will be randomly allocated into one of two groups:

• Phenylephrine group (n=100)
• Norepinephrine group (n=100)

Patients who shows SBP above 140 mmHg or heart rate below 55 bpm after the first vasopressor dose will not receive the infusion. The infusion will stop if the SBP was above 140 mmHg or if the heart rate was below 55 bpm. Patients will be positioned in the supine position with left lateral tilt. Block success will be assessed using pinprick, patients with failed block will be excluded from the study. The highest sensory block level will be assessed after 5 minutes from intrathecal injection. Co-hydration will be continued till maximum of 1.5 litres.

Enrollment: 200 patients

Sex: Female

Ages: 18 to 35 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• full term singleton parturients
• elective cesarean sections

Exclusion criteria

• cardiac morbidities
• hypertensive disorders of pregnancy
• peripartum bleeding
• body mass index > 35 will be excluded from the study

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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200 participants in 2 patient groups

phenylephrine,

Active Comparator group

Description:

- Phenylephrine group (n=100): will receive 100 mcg phenylephrine as a single bolus just after intrathecal injection of 10 mg bupivacaine plus 20 mcg fentanyl. The dose will be diluted in 5 mL and given over seconds. A continuous infusion with placebo (normal saline) will start after the first bolus.

Treatment:

Drug: Fentanyl

Drug: Placebo (normal saline)

Drug: phenylephrine

Drug: Bupivacaine

norepinephrine

Active Comparator group

Description:

- Norepinephrine group (n=100): will receive bolus of norepinephrine (10 mcg) directly after spinal block using 10 mg bupivacaine plus 20 mcg fentantanyl followed by continuous infusion of norepinephrine with a rate of 0.1 mcg/kg/min till delivery of the fetus.

Treatment:

Drug: Fentanyl

Drug: Norepinephrine

Drug: Bupivacaine