In this study, the investigators measure a pupil size every 5 minutes during the operation in patients undergoing laparoscopic cholecystectomy under general anesthesia. The investigators would compare the intraoperative opioid consumption and postoperative pain between the group adjusted the anesthetic drug concentration based on the changes of the pupil (Pupil group) and the group based on the changes of a surgical pleth index (SPI group).
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
SCREENING
Masking
QUADRUPLE
Enrollment
50
At least 10 min after anesthesia induction by target-controlled infusion of propofol and remifentanil, baseline values for pupillary diameter is recorded before any surgical procedure. During the operation, propofol effect-site target concentration (Ce) is adjusted to maintain the bispectral index (BIS) value between 40 and 60. Remifentanil Ce is adapted every 5 min based on the changes of pupillary diameter. If the pupillary diameter is increased by more than 30% compared to baseline value, remifentanil concentration is increased by 0.5 ng/ml. If the pupillary diameter is maintained between 5 and 30 % change compared with baseline, remifentanil is not modified. In a case of pupillary diameter is decreased less than 5 % change of baseline, remifentanil concentration is decreased by 0.5 ng/ml.
During the operation, SPI value should be maintained between 20 and 50 by changing the infusion rate of remifentanil. Even if the SPI is maintained within the target range, the remifentanil infusion rate is increased by 0.5 ng/ml in a case of the SPI value suddenly arises by more than 10.
During the operation, propofol effect-site target concentration (Ce) is adjusted to maintain the bispectral index (BIS) value between 40 and 60. Remifentanil concentration is controlled by the discretion of the anesthesiologist in charge of the patients.
Eugene Kim
Daegu, Nam-gu, South Korea
Intraoperative opioid consumption
The amount of remifentanil consumption during the operation is calculated by following equation: Total remifentanil consumption (mcg) / body weight of the patients (kg)/ duration of anesthesia (min)
Time frame: During the operation period (Within 2 hour after the anesthesia induction)
Peak pain score assessed by numeric rating scale (NRS) in post-anesthesia care unit (PACU)
Patients are asked to rate their pain according to the numeric rating scale (NRS, 0=no pain to 10= extreme pain imaginable) every 10 min after the PACU admission. Peak pain score is the peak NRS during PACU stay. Higher NRS represents a worse outcome.
Time frame: During the PACU stay (Within 1 hour after the PACU admission)
Intraoperative propofol consumption
The amount of propofol consumption during the operation
Time frame: During the operation period (Within 2 hour after the anesthesia induction)
Intraoperative vasopressor or vasodilator consumption
The amount of ephedrine and nicardipine consumption during the operation
Time frame: During the operation period (Within 2 hour after the anesthesia induction)
PACU stay time
Duration of time interval from PACU admission to discharge.
Time frame: Approximately within 1 hour after the PACU admission
Postoperative adverse events
Check the postoperative nausea and vomiting, dizziness, desaturation, urinary retention, itching sensation and bradycardia
Time frame: Approximately within 1 hour after the PACU admission
Remnant sedation degree
Remnant sedation is evaluated by Riker Sedation-Agitation Scale every 10 minutes after the PACU admission. 1. unarousable, minimal or no response to noxious stimuli, does not communicate of follow commands 2. very sedate, arouse to physical stimuli but does not communicate or follow command, may move spontaneously 3. sedate, difficult to arouse but awakens to verbal stimuli or gentle shaking, follows simple commands but drifts off again 4. Calm and cooperative, calm and follows commands 5. agitated, anxious or physically agitated and calms to verbal instructions 6. very agitated, requiring restraint and frequent verbal reminding of limits, biting endotracheal tubes 7. dangerous agitation, pulling at tracheal tube, trying to remove catheters or striking at staff
Time frame: Approximately within 1 hour after the PACU admission
Total analgesic consumption after PACU discharge
Check the analgesic consumption after PACU discharge including oral, intramuscular and intravenous administration.
Time frame: During 1 day after the operation
Pain score assessed by numeric rating scale (NRS) 1 day after the operation
Patients are asked to rate their pain according to the numeric rating scale (NRS, 0=no pain to 10= extreme pain imaginable) 1 day after the operation. Higher NRS represents a worse outcome.
Time frame: On 1 day after the operation
initial Pupillary unrest under ambient light (PUAL)
At room light, the pupil is taken for 8 seconds at a frame rate of 30 frames per second. The pupillometer generates raw data in the format of pupil diameter versus time. We define the PUAL as the area under the curve of power spectral density between 0.23 and 3 Hz. The integral of the area is calculated using the composite Simpson's rule.
Time frame: Just before the induction of anesthesia
Pupillary unrest under ambient light (PUAL) on PACU arrival
At room light, the pupil is taken for 8 seconds at a frame rate of 30 frames per second. The pupillometer generates raw data in the format of pupil diameter versus time. We define the PUAL as the area under the curve of power spectral density between 0.23 and 3 Hz. The integral of the area is calculated using the composite Simpson's rule.
Time frame: Approximately within 1 min after the PACU admission
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