Carotid Doppler Peak Velocity Variation in Liposuction Fluid Management

The research will involve 50 female participants who have undergone liposuction and will be divided into two groups. Group 1: Fluid administration will be determined by the intraoperative fluid ratio. This ratio is calculated by dividing the sum of subcutaneous infiltration and intravenous fluid by the total aspirate volume. Depending on the aspiration volume, it will be maintained at 1-1.4. Group 2: Participants will be given a fluid maintenance rate of 1.5 ml/kg/h. To determine fluid responsiveness, the carotid artery peak velocity variation (ΔVPeak-CA) will be measured before, during, and after the procedure. If the ΔVPeak-CA goes above 15%, the patient will receive a fluid bolus of lactated ringer solution at a rate of 4-6 ml/kg over 10-15 minutes, and the team will re-measure fluid responsiveness 10 minutes after each ΔVPeaK-CA. During the examination, a single cardiothoracic anesthesiologist will use a 13-6 MHz linear probe (Fujifilm Sonosite M-Turbo) to measure the peak velocity of the carotid artery on the left side. The sample volume will be positioned at the center of the lumen, 2 cm from the bulb, and a pulsed wave Doppler examination will be conducted. To measure the ΔVPeak-CA, the investigators will calculate the maximum and minimum values during one respiratory cycle. This will be done by using the formula: 100x (maximum peak velocity - minimum peak velocity) / \[(maximum peak velocity + minimum peak velocity)/2\]. Surgical technique The superwet tumescence technique will be the only method utilized for infiltration during the procedure. All participants will undergo power-assisted liposuction, and a single surgeon will operate. The wetting solution will contain 1000cc of normal saline and 2mg of epinephrine in a 1:500,000 ratio. The total Infiltration volume will depend on the patient. The total amount of aspiration will depend on the patient and surgery plan and can vary between 2500 to 5000 ml During the surgical procedure, the investigators will monitor vital signs such as blood pressure, heart rate, temperature, oxygen levels, and urine output. Additionally, the investigators will track the amount of fluids given and removed, and the volume of blood aspirated. Following surgery, participants will be hospitalized for 24 hours. During this time, the investigators will closely monitor the plethysmography variability index (PVI) in both groups. If the PVI exceeds 15%, participants will receive a ringer lactate fluid bolus of 4-6 ml/kg. Additionally, the investigators will keep track of their urine output, total fluid intake, and vital signs