Comparison of Two Different Anesthetic Techniques on Incidence of Postoperative Delirium in Cancer Patients After Laparoscopic Surgery in Trendelenburg Position: A Prospective Randomized Clinical Trial

Postoperative delirium is an acute mental syndrome that is caused by diffuse cerebral dysfunction resulting from the action of predisposing and precipitating factors acting together. It is associated with an increase in mortality and postoperative morbidity and prolongs the period of hospitalization of the patient Videolaparoscopic surgery has been increasingly used as a therapeutic and diagnostic method. In order to have a good visualization of the anatomical structures on which it will act, it is necessary to introduce gas into the cavity, a mandatory component known as pneumoperitoneum. This technique gives special characteristics for the conduction of anesthesia, since the positive intra-abdominal pressure results in changes in the patient's physiology. Some types of laparoscopic surgery require the position of Trendelenburg for better visualization of the operative field. Among the changes related to this position are the increase in cardiac output and intracranial pressure.

In order to optimize the anesthetic procedure, anesthetic blocks have been increasingly used, especially the spinal. The association of general anesthesia with spinal anesthesia, followed by its contraindications is advantageous, because lower doses of anesthetic agents are necessary for the maintenance of general anesthesia. This association results in an earlier awakening, a reduction of nausea / vomiting, postoperative pain, length of hospital stay, cost effectiveness and greater patient satisfaction. As a disadvantage, by associating general anesthesia with spinal anesthesia, patients become susceptible to the adverse events of spinal anesthesia. Among these, the most common are headache, hypotension, nausea and vomiting, pruritus, urinary retention and tremor. Performing spinal anesthesia with opioids alone, without the use of local anesthetic is also possible, with morphine being the most used. The benefit of this variation of technique is analgesia for a period of 12 to 24 hours, without the cardiovascular consequences resulting from the action of the local anesthetic.

JUSTIFICATION: There are no studies in the literature evaluating The objective of this study is to analyze if the anesthetic techniques employed, general anesthesia or general anesthesia associated with subarachnoid block, for videolaparoscopic oncologic surgeries, in Trendelenburg position, differ in relation to the incidence of delirium in the postoperative period.