Introduction

The choice of anaesthetic agents and techniques could  influence the occurrence of complications such as postoperative nausea and vomiting (PONV), postoperative behavioural disturbances and cardiorespiratory complications and thus delay discharge. Dilatation and curettage(D&C) procedures that involve general anaesthesia are performed with combination of intravenous with  volatile anaesthetics or propofol-based total intravenous anaesthesia. Both these techniques are safe and provide appropriate conditions for surgery. Total inhalation anesthesia is a general anesthetic that uses only inhaled anaesthetics drugs to induce and maintain unconsciousness and is rarely used .Hence it is  unclear whether TIVA or TIA  anaesthesia regimen is better for  short day care procedures like D&C. The present study will be conducted to compare the use of the inhalation anaesthesia technique using sevoflurane and nitrous oxide with the TIVA technique, using propofol and fentanyl.The primary objective of the study will be to compare the incidence and severity of post operative nausea and vomiting between patients receiving inhalational and those receiving total intravenous anaesthesia.

Methods

After obtaining approval from the hospital Ethics Committee and securing the CTRI clearance, patients will be randomly allocated to either of the two groups [Group P or Group S ] using computer generated random sequence of numbering. Concealment of allocation will be ensured by sequentially numbered opaque sealed envelopes.

Female surgical patients scheduled for D&C procedure will be recruited after a thorough pre-anaesthetic evaluation and consent.

Patients will be fasted 6 hours for solids and 2 hours for clear fluids. No premedication will be given as per the hospital protocol. Pre operatively, on the day of surgery, patients will be explained about the procedure, satisfaction scores and consent will be taken.

In the operation theatre, an intravenous line will be secured and injection glycopyrrolate 0.2mg will be  given to all patients and all pre induction monitors-ECG, NIBP, saturation probe and EtCO₂will be attached.

Patients in group P will be induced with iv midazolam 2mg,  fentanyl 1.5mcg/kg, ketamine 0.5mg/kg and titrated doses of propofol till the patient loses consciousness. Additional increments of 10mg propofol will be given when the patient shows signs of inadequate anaesthesia like spontaneous movement, resistance to leg elevation during positioning of the patient or an increase in heart rate or BP and increase in the depth of ventilation. The patients in group S will be induced with 50% nitrous oxide and 5% sevoflurane in oxygen till loss of consciousness and then sevoflurane will be reduced to 2%.

Patients in both groups will be maintained on spontaneous ventilation with a face mask and closed circuit.

All patients will be provided with iv 4mg Ondansetron and 1g paracetamol at the end of surgery. The time to respond to commands after surgery and the surgeon’s satisfaction with anaesthesia provided will be noted in both groups.

PONV, requirement of additional anti-emetic and analgesic, patient satisfaction, time to ambulate and discharge the patient and the cost of anaesthesia will also be noted.