Carbohydrate Loading Fasting Protocol Versus 'Sip Til Send'

This is a study focused on comparing fasting policies that are in use at the Rotunda.

Investigators wish to determine the best fasting policy for women at elective caesarean delivery by focusing on assessing outcomes related to the patient experience.

A 'Sip til send' fasting policy means women may drink clear fluid up until the time they are called from the ward to come to theatre for their elective caesarean delivery. This policy was implemented at the Rotunda in 2022 and was studied prospectively, investigators demonstrated improvements in the comfort that women experience in their perioperative journey, compared to a traditional fasting protocol where women must fast for many hours for both fluids and solids before they come to theatre.

It has been shown that oral carbohydrate intake may improve outcomes in general and cardiac surgeries, but there is very limited evidence in obstetrics. The Rotunda is increasingly providing women with carbohydrate drinks prior to CD. These drinks are consumed by the patient on the morning of surgery as part of an enhanced recovery after surgery (ERAS) package. There is little evidence to support the use of carbohydrate drinks, but current thinking is that they may increase energy and comfort and reduce metabolic changes due to prolonged fasting.

Pregnant women are more vulnerable to the side effects related to the extended fasting due to the accelerated fasting in the third trimester of pregnancy after an overnight fast pre-operatively. Carbohydrate reserves are rapidly exhausted, causing hypoglycemia, increased urine nitrogen secretion (indicating muscle catabolism), and increased urinary ketone body concentration. It has been recommended that Mothers in their third trimester avoid skipping meals.

Investigators wish to study the effects of integrating carbohydrate drinks into the current 'sip til send' fasting protocol and determine if these women benefit from either protocol.

Inclusion criteria

• Elective caesarean section for singleton pregnancy under neuraxial anaesthesia.
• Subjects able to give informed consent and willing to comply with the study protocol.
• Subjects must be greater than 18 years old

Exclusion criteria

• Diabetes Mellitus - including gestational diabetes.
• Known foetal abnormality.
• Planned general anaesthesia.
• Elective caesarean delivery at a gestation of less than 37 weeks.
• Low birth weight 2.5 kg (IUGR)
• BMI greater than 45 kg/m2
• Women with severe gastro-oesophageal reflux disease