780 INTRAOCULAR PRESSURE INCREASE DURING ROBOT ASSISTED LAPAROSCOPIC PROSTATECTOMY: BALANCED ANESTHESIA VERSUS TOTAL INTRAVENUS ANESTHESIA

INTRODUCTION AND OBJECTIVES: Permanent visual loss during non-ophthalmic surgery is a rare but devastating cause of post-operative morbidity. One common diagnosis is ischemic optic neuropathy due to the excessive increase of intraocular pressure (IOP) during procedure. Robot-assisted laparoscopic prostatectomy (RALP) needs patients are positioned on operating table tilted about 30–35 degrees and the pneumoperitoneum pressure is about 13 mmHg; those factors lead to IOP increase. In addition volatile or intravenous anesthetics contribute to increase IOP. Anesthesiologist has to provide adequate control of IOP. METHODS: We performed a prospective, randomized study to compare the effects of volatile versus intravenous anesthetics on IOP increasing during RALP. IOP was measured using OBF Langham System tonometer in ASA I and II patients undergoing elective RALP. 40 patients were randomized in 2 groups: group B received balanced anesthesia with volatile anesthetics, group T received total intravenous anesthesia with propofol and remifentanil. Exclusion criteria were adverse reactions to any of the anesthetic agents used in the study and ophthalmic disease. The IOP was measured before anesthesia while supine and awake (baseline or T0), anesthetized and supine after induction (T1), anesthetized after insufflation of the abdomen with carbon dioxide (CO2) in steep Trendelenburg at the beginning (T2) and at the end of the surgery (T3), finally anesthetized supine before awakening (T4). The primary end point of our study was to investigate any differences in IOP of patients underwent balanced versus total intravenous anesthesia. RESULTS: T0 was 18,8 1,7 mmHg in Group T and 18,7 1,6 mmHg in Group B. IOP decreased to a minimum of 12,2 3,1 mmHg after induction (T1) in Group T and to 13,2 4 mmHg in Group B. At time point T2 IOP was 25,4 3,8 in Group T, significally lower than in Group B, 30,2 6,2 (p 0,015). IOP at T3 was lower in Group T, 29.9 3 than is Group B, 34,2 4,3 (p 0,004). At T4 IOP decreases to 21,8 3,5 in Group T and 22,8 4,9 in Group B. CONCLUSIONS: During RALP IOP reaches levels that are comparable with those observed in glaucoma patients in both of the groups. Our results demonstrate that the increase of IOP was more pronounced and sustained in the balanced anaesthesia as compared with total intravenous anesthesia. IOP increase may not be of any consequence in the majority of patients undergoing RALP, but it may be harmful in patients with glaucoma. We conclude that total intravenous anesthesia is the safer anesthetic regimen during RALP, especially in patients at risk.