Dosage of Intrathecal Hyperbaric Bupivacaine and the Incidence of Post Spinal Shivering.

After approval of the ethics committee, department of anaesthesia, Menoufia University and written informed consent, a hundred full-term pregnant ladies undergoing elective cesarean section were enrolled in this study.

The pregnant ladies were randomly assigned using a computerised software to one of two groups, low dose bupivacaine (LB) and high dose bupivacaine (HB), 50 patients each according to bupivacaine dose. Group LB received low dose bupivacaine (8 mg hyperbaric bupivacaine) Group HB received high dose bupivacaine (10 mg hyperbaric bupivacaine).

Vital signs including heart rate and mean arterial blood pressure intra-operatively until the end of surgery.

The severity of shivering was the primary endpoint. Shivering was graded using a scale: 0, no shivering; 1, piloerection but no visible muscle activity; 2, muscular activity in one group of muscle; 3, muscular activity in more than one muscle group but not generalized movement; and 4, shivering involving the movement of the whole body. Shivering score was recorded for the whole study period.

Inclusion criteria

• Patients aged between 22 and 35 year old, and American Society of Anesthetists (ASA) I or II were included in the study and consented to have spinal anaesthesia for their section.

Exclusion criteria

• Patients who had contraindication to spinal anesthesia, high-risk pregnancy, history of seizures, mental illness, acute fetal distress, and patients refused spinal anesthesia were excluded from the study.