Table 1.

Anaesthesia protocol for intraoperative monitoring during spine surgery used in this study

Protocol of anaesthesia
Remifentanyl (Ultiva)	Induction 0.1–0.2 μg/kg/min for 3 min	Maintain dose 0.4 (0.2–0.8) μg/kg/min, mainly dependent on heart frequency and blood pressure
Propofol (Disoprivan)	Bolus 0.2–0.25 mg/kg 10 mg/kg/h for 10 min, then 5 mg/kg/h until start of the operation	4 (3–12) mg/kg/h during operation
Ketamin (Ketalar)	Not used for induction	2–6 mg/kg/h, instead of, or in combination with propofol
Recuronium (Esmerol)	0.6–0.9 mg/kg	Only for intubation
Sevofluran, N2O,...	Seldom used	Not used