In the reduction mammoplasty operations performed in the Plastic and Reconstructive surgery operating room in our clinic, the female patient group, who does not have co-morbidities and does not exceed middle age, is followed by infusion of crystalloid at a constant rate of 4 ml/kg. If the mean arterial pressure (MAP) is \<65 mmHg, it is treated with fluid boluses, and in cases where no response is obtained, with noradrenaline boluses. However, in this process, frequent and severe hypotensive episodes are observed, especially after removal of more than a few kilograms of breast tissue. In these hypotensive episodes, factors other than the blood volume lost with the tissue may also play a role. For this reason, we aimed to evaluate the iNOS levels by assuming that the blood levels of "inducible nitric oxide synthetase" (iNOS), which is stored in large amounts in adipose tissues and has been shown to play a role in lipid metabolism, may increase with the manipulation of breast tissue, and accordingly increased nitric oxide may lead to hypotension.
The main purpose of intraoperative fluid therapy is to optimize intravascular volume, mean arterial pressure (MAP) and cardiac output, while ensuring tissue perfusion, while not causing dehydration and fluid overload in the patient. While hypovolemia may cause problems such as organ perfusion disorders and ischemia; Hypervolemia may lead to pulmonary edema, cardiac load, prolonged need for mechanical ventilation and susceptibility to related infections. Although fluid management in the perioperative period has been extensively studied in many studies, a standard practice has not been established. The amount considered restrictive in some studies may be liberal in others. In recent years, the use of dynamic parameters, which are formed as a result of cardiopulmonary interactions and whose high sensitivity and specificity have been proven by many studies, has been increasing day by day for the evaluation of intravascular volume. Pulse pressure variation(PPV) and stroke volume variation(SVV) are two of these dynamic parameters. The pulse contour cardiac output (FloTrac) system, which is a fairly newly developed method that calculates cardiac output and stroke volume directly from the arterial waveform, is used for measurement without the need for calibration. In the reduction mammoplasty operations performed in the Plastic and Reconstructive surgery operating room in our clinic, the female patient group, who does not have co-morbidities and does not exceed middle age, is followed by infusion of crystalloid at a constant rate of 4 ml/kg. If the mean arterial pressure (MAP) is \<65 mmHg, it is treated with fluid boluses, and in cases where no response is obtained, with noradrenaline boluses. However, in this process, frequent and severe hypotensive episodes are observed, especially after removal of more than a few kilograms of breast tissue. In these hypotensive episodes, factors other than the blood volume lost with the tissue may also play a role. For this reason, we aimed to evaluate the iNOS levels by assuming that the blood levels of "inducible nitric oxide synthetase" (iNOS), which is stored in large amounts in adipose tissues and has been shown to play a role in lipid metabolism, may increase with the manipulation of breast tissue, and accordingly increased nitric oxide may lead to hypotension.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
40
Isotonic solutions are IV fluids that have a similar concentration of dissolved particles as blood.
Noradrenaline itself is classified as a sympathomimetic drug: its effects when given by intravenous injection of increasing heart rate and force and constricting blood vessels make it very useful for treating medical emergencies that involve critically low blood pressure.
Istanbul University, Department of Anesthesiology
Istanbul, Fatih, Turkey (Türkiye)
RECRUITINGCardiac index
Cardiac index (CI) is a haemodynamic parameter that relates the cardiac output (CO) from left ventricle in one minute to body surface area (BSA),thus relating heart performance to the size of the individual. The unit of measurement is litres per minute per square metre (L/min/m2).
Time frame: during surgery
Number of bolus administrations of noradrenaline
For the MAP group, if MAP is still below 65 mmHg despite a bolus of 250ml isotonic fluid, a bolus of 4mcg noradrenaline will be administered, if no response, 4mcg noradrenaline will be repeated. For the SVV Group, a 4 mcg bolus of noradrenaline will be given if MAP\< 65 mmHg despite the SVV falling below 14% with isotonic boluses.
Time frame: during surgery
Number of bolus administrations of isotonic fluid
For the MAP group, the number of administrations of 250 ml of isotonic fluid delivered in 10 minutes when MAP \< 65 mmHg For the SVV group, the number of administrations of 250 ml of isotonic fluid administered in 10 minutes when SVV≥ 14%
Time frame: during surgery
The Number of Hypotensive Episodes
The number of times the MAP value falls below 65mmHg during surgery
Time frame: during surgery
Intraoperative Fluid Balance
the difference between the amount of urine output and the amount of bleeding from the amount of fluid given
Time frame: during surgery
Plasma iNOS Levels
difference in serum iNOS levels preoperatively and after removal of mammoplasty material
Time frame: Up to 6 hours
Lactate value
Values measured by perioperative arterial blood gas analysis
Time frame: Up to 6 hours
Base deficit value
Values measured by perioperative arterial blood gas analysis
Time frame: Up to 6 hours
Creatinine value
Blood level is checked on the preoperative and postoperative 1st day
Time frame: Preoperative and Postoperative 1st day
Urea value
Blood level is checked on the preoperative and postoperative 1st day
Time frame: Preoperative and Postoperative 1st day
Hemoglobin value
Blood level is checked on the preoperative and postoperative 1st day
Time frame: Preoperative and Postoperative 1st day
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