Effect of surgical plethysmography index on perioperative opioid use in patients undergoing laparoscopic nephrectomy under general anesthesia - A randomized controlled study

Though systemic opioids are commonly used and provide good pain relief, there is an increase incidence postoperative nausea and vomiting, urinary retention,respiratory depression and especially in cancer patients several studies have shown that tumor recurrence and decreased disease free and overall survival rate. As it is impossible to completely do away with perioperative opioid use, emphasis has been on opioid sparing analgesia.

To support this a search for newer modality has been increased which easy and inexpensive. Surgical pletysmography is new modality used to monitor nociceptive stimuli and anti-nociceptive drug effect during surgery using the pulse wave photoplethysmographic amplitude and heart rate interval derived from pulse oximetry measurements, represents the mean surgical stress level during anaesthesia.

The present study is planned to evaluate the utility of SPI ( surgical plethysmograhic index ) in providing opioid sparing analgesia.

This study is a randomized double blinded study which will be done in patients scheduled for laparoscopic radical nephrectomy.

Conduct of study as follows, Patients are divided are into 2 groups, that is SPI- guided analgesia group injection fentanyl will be given @IV 0.5mcg/kf bolus when SPI above 50 for more than 5min. other group is that is Control group, injection fentanyl was given at standard practice based on changes in heart rate and blood pressure >20% of the base line.