Hemodynamic changes outside of the normal range i.e., hypertension (systolic blood pressure greater than 140 mm Hg), tachycardia (heart rate greater than 90 min-1) and hypotension (mean arterial pressure less than 60 mm Hg) will be first assessed using the guidance of Bispectral index and Train of four monitors. Sufentanil in doses of 2.5 to 5 mcg (maximum of 0.6-1.2 mic/kg for the entire surgery) is administered if the Bispectral index and Train of four monitor values are within normal range and if required vasopressor infusion is used. Vasoconstrictors may be given as a continuous infusion of norepinephrine, or bolus doses of ephedrine or phenylephrine. Only when blood pressure remains, low additional crystalloids will be given. Finally, in case of bradycardia (heart rate less than 30 min-1), atropine may be given

In the nociception level-guided group, sufentanil will be administered to maintain a nociception level value between 10 and 25. In case the nociception level values rise greater than 25 for more than 60 s, additional 2.5 microgram sufentanil (if nociception level increase remained less than 45) or 5 micrograms (if nociception level increase greater than 45). Atropine will be administered when heart rate decreases less than 30 min-1. Because the nociception level may be sensitive to such medication, nociception level values will then not used for at least 5 min to guide analgesia, with the exception of norepinephrine as this drug will be given as continuous infusion

NOL technology uses a multiparameter-based sensor platform, and advanced algorithm, to continuously monitor Autonomic Nervous System (ANS) functions. NOL reflects a patient's nociceptive state and analgesic effect, helping to optimize the administration of systemic and/or regional analgesics, and avoiding overdose or underuse of these drugs. The nociception level is a multiparameter monitor that combines information from the finger photoplethysmogram amplitude, skin conductance, skin conductance fluctuation, heart rate, heart rate variability, and their time derivatives into one index ranging from 0 (absence of noxious stimulation) to 100 (severe noxious stimulation).

Amount of sufentanil in micrograms administered during the entire operative period i.e. from induction of anaesthesia up to transfer to the recovery room

The RR discharge score is a scoring system developed for general surgery by the Danish Society of Anesthesia and Intensive Care. The score consists of 5 semi-objective variables (sedation, respiration, nausea, pain, and motor function) and 5 objective variables (peripheral saturation, diuresis, arterial blood pressure, heart rate and temperature). The nurses score each variable from 0 to 3 points. Low scores( below 3 for 2 consecutive hours) indicate a stable condition, and patients are considered eligible for discharge. The score values at different time points represent the quality of recovery.