Neuroendocrine stress response in gynecological laparoscopy: TIVA with propofol versus sevoflurane anesthesia.

STUDY OBJECTIVE: To compare intraoperative and postoperative neuroendocrine stress responses during total intravenous anesthesia (TIVA) using propofol and remifentanil versus sevoflurane anesthesia, during laparoscopic surgery. DESIGN: Prospective, randomized study. SETTING: Tertiary-care university hospital. PATIENTS: 46 ASA physical status I patients undergoing laparoscopic surgery for benign ovarian cysts. INTERVENTION: Patients were randomly allocated to two groups to receive either TIVA (Group A=23) or sevoflurane anesthesia (Group B=23). MEASUREMENTS: Perioperative plasma levels of norepinephrine (NE), epinephrine (E), adrenocorticotropic hormone (ACTH), cortisol, growth hormone (GH), prolactin (PRL), and thyroid hormones (TSH, FT3, FT4) were measured. Blood samples were collected preoperatively, 30 minutes after the beginning of surgery, after extubation, and two and 4 hours after the end of surgery (times 0, 1, 2, 3, and 4). MAIN RESULTS: In Group A, perioperative levels of NE, E, ACTH, cortisol, and GH compared with preoperative values significantly decreased; in Group B they increased (Groups A vs. B: time 1, P<0.001 for all markers; time 2, P<0.001 for E, ACTH, cortisol, and GH; time 3, P<0.01 for cortisol, NE, and E, and P<0.05 for ACTH and GH). Perioperative PRL levels were significantly enhanced in both groups versus preoperative values. In both groups, TSH levels increased while FT3 levels decreased significantly relative to basal values. In both groups, perioperative FT4 levels significantly increased compared with preoperative values. CONCLUSIONS: TIVA inhibited the ACTH-cortisol axis and reduced NE, E, and GH levels, but it enhanced PRL and had a weak effect on thyroid hormone concentrations as compared to sevoflurane anesthesia.

Diastolic function: the influence of pneumoperitoneum and Trendelenburg positioning during laparoscopic hysterectomy.

BACKGROUND AND OBJECTIVE: Several reports concerning the haemodynamic changes during gynaecologic laparoscopy have been published so far, and the effects of head-down tilt and pneumoperitoneum have not been clearly separated. However, its main effect seems to be an increase in systemic vascular resistance. We investigated how the augmented afterload can affect diastolic function. METHODS: : Our study involved 20 healthy women, classified as having ASA status I: 10 undergoing laparoscopic hysterectomy and 10 undergoing conventional open hysterectomy. Measurements were made in awake patients and after induction of anaesthesia and then repeated after carbon dioxide insufflation and head-down positioning and at the end of surgery. Diastolic function was primarily studied by transthoracic echocardiography. RESULTS: We observed that pneumoperitoneum caused a significant reduction in stroke volume, cardiac output and left ventricular end-diastolic volume; the diastolic filling times showed a progressive reduction in the E-velocity (the velocity of early mitral inflow, corresponding to the ventricular passive filling phase, measured by pulsed-wave Doppler), a prolonged deceleration time and an augmented isovolumetric relaxation time. After head-down tilting, stroke volume, cardiac output and left ventricular end-diastolic volume increased in both laparoscopic hysterectomy and conventional open hysterectomy groups. CONCLUSION: We have found that pneumoperitoneum has important effects on left ventricular volumes, causing a drop in left ventricular end-diastolic volume; it also affects diastolic function with a delay in deceleration time and isovolumetric relaxation time without any effects on intracavitary pressures.