Anesthesia
Conditions
Keywords
Epidural top-up, Shivering, Magnesium
Brief summary
Magnesium has been shown to decrease the shivering experienced from neuraxial anesthesia. This study aims to investigate whether magnesium decreases the shivering experienced in parturients undergoing labor epidural anesthesia for Cesarean delivery.
Detailed description
Women who have epidurals in place and go on to require a Cesarean delivery typically have their epidurals 'topped-up' with a fast onset local anesthetic to ensure the lower body is fully numb for surgery. This is called an epidural 'top-up'. However, a side effect of epidural top-ups is shivering, which is uncomfortable for the mother and interferes with patient monitoring. Magnesium administration has been shown to decrease shivering in the non-pregnant population. Therefore, in this study the investigators aim to determine if magnesium given prior to an epidural top-up decreases the incidence and severity of shivering in the pregnant population.
Interventions
DRUGMagnesium Sulfate
Bolus infusion: 100mL normal saline with 4g MgSO4 over 30 minutes Maintenance infusion: 25mL normal saline per hour with 1g MgSO4
OTHERNormal Saline
Bolus infusion: 100mL normal saline over 30 minutes Maintenance infusion: 25mL normal saline per hour
Sponsors
University of British Columbia
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
FEMALE
Age
19 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
1. Gestational age of ≥37 weeks 2. Women who are ≥ 19 years old 3. Women undergoing Cesarean delivery under lidocaine top-up via a preexisting epidural catheter inserted for labor analgesia 4. American Society of Anesthesiologist (ASA) Physical Status class 1 or 2
Exclusion criteria
1. Emergency Cesarean delivery with limited time for informed consent 2. Women who have received MgSO4 prior to study enrollment 3. Indication for alternative mode of anesthesia for Cesarean delivery (e.g., general anesthesia) 4. Medical conditions or medications that could lead to tremor or shivering. (e.g., movement disorder, untreated thyroid disease) or mask tremor or shivering (e.g., beta-blocker, benzodiazepine, anticonvulsants) 5. Active shivering at time of recruitment 6. Inability to read and understand English for the purpose of informed consent 7. Contraindications to receiving MgSO4 (hypersensitivity reactions, respiratory rate \<16breaths/min, absent reflexes, urine output \<100 mL during the previous 4 hours, renal failure, or hypocalcemia) 8. History of previous postpartum hemorrhage
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of intraoperative shivering | Through completion of cesarean surgical procedure (maximum 2 hours) | Incidence measured as shivering present or absent |
| Severity of intraoperative shivering | Through completion of cesarean surgical procedure (maximum 2 hours) | Severity measured subjectively by anesthesiologist and patient |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of hypothermia | Through study completion (maximum 2.5 hours) | Number of patients whose tympanic membrane temperature decreases below 36 degrees Celsius. |
| Incidence of hypotension | Through study completion (maximum 2.5 hours) | Number of patients who experience a greater than or equal to 20% reduction in systolic blood pressure. |
| Total vasopressor(s) dose | Through study completion (maximum 2.5 hours) | — |
| Total utertonic(s) dose | Through completion of cesarean surgical procedure (maximum 2 hours) | — |
Countries
Canada
Outcome results
None listed