A preoperative warming regime versus no preoperative warming for maintenance of normothermia in women receiving intrathecal morphine for caesarean section.

Women receiving intrathecal morphine for caesarean section receiving preoperative warming versus no preoperative warming for maintenance of normothermia.

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12614001088639

Enrollment

Registered

2014-10-10

Start date

2015-02-04

Completion date

2016-02-10

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Women undergoing caesarean section experience high rates of heat loss and hypothermia related to surgery and anaesthesia. As well as causing discomfort, hypothermia experienced during and after anaesthesia and surgery is also associated with many adverse effects, for example increased blood loss. It is also thought that spinal morphine, commonly given during caesarean section for pain relief, may also exacerbate heat loss. This project aims to test warming patients preoperatively via a warming blanket (which utilises heated air) to reduce the amount of heat loss during surgery. A randomised controlled study design will be used: the control group will receive normal care while the intervention group will receive preoperative warming. Potential participants will be identified via the surgical booking process. Recruitment and informed consent will occur at the preoperative assessment appointment. Participants will be randomly assigned, on the day of surgery, to either the control group receiving usual care, or the intervention group receiving preoperative warming. Temperature will be recorded throughout the preoperative period, during surgery and during the postoperative period in the recovery unit. Data will be analysed to investigate differences in the amount of temperature lost (temperature decline) in each group and comparisons made. Thermal comfort experienced by mothers will also be determined, as well as the incidence of shivering. Comparisons will also be made between newborn temperature and Apgar scores (used to assess the health of the newborn).

Interventions

A 20 minute period of full body preoperative warming using a Cocoon (Trademark) forced air warming device, whilst the patient is waiting in the preoperative waiting area and immediately before transfer to the operating theatre for induction of spinal anaesthesia. Forced air warming will be administered via a full body warming blanket applied whilst participants are sitting in a recliner. The temperature setting applied will be 43 degrees celsius.

Study design

Allocation

Randomised controlled trial

Intervention model

Parallel

Primary purpose

Prevention

Masking

Blinded (masking used) (Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

Women receiving intrathecal morphine whilst undergoing spinal anaesthesia for elective caesarean section at the Mater Mother’s hospital.

Exclusion criteria

Emergency caesarean section Epidural top-up, general anaesthesia or epidural opiates during combined spinal-epidural Women not receiving intrathecal morphine during spinal anaesthesia for caesarean section Known allergy to morphine Admission temperature of > 37 degrees celsius Known impaired thermoregulation or thyroid disorders Tympanic membrane/aural canal not visible on otoscopy Vascular disease or poor cutaneous perfusion Planned postoperative ICU admissions American Society of Anesthesiologist’s (ASA) score > II History of preeclampsia or eclampsia. Delay between completion of warming intervention and the transfer to theatre that is greater than 20 minutes.

Outcome results