Effect of three pretreatment techniques on hemodynamic and CSFP responses to skull-pin head-holder application during thiopentone/isoflurane or propofol anesthesia

The effects of three different pretreatment techniques on ICP and MAP responses to pin head-holder application (HH) were studied. Thirty-two patients for elective intracranial surgery were assigned randomly to three pre-treatment groups: group I-local scalp infiltration with lidocaine (6-8 ml of 2% solution); group II-deepening of general anesthesia with either thiopentone (2 mg/kg) or propofol (0.6 mg/kg); and group III-intravenous fentanyl (4 mug/kg). Two anesthetic techniques were used, subdividing the three groups into subgroup A (thiopentone-isoflurane) and subgroup B (propofol). Measurements of MAP, cerebrospinal fluid pressure (CSFP), cerebral perfusion pressure (CPP), and heart rate (HR) were made at pretreatment, just before HH (time T0: baseline), and 0.5, 1, 2, 3, 4, and 5 min after HH. Within each group, MAP, HR, CPP, and CSFP varied similarly in both subgroups, so the data from A and B were cumulated. After HH application, MAP, HR, CPP, and CSFP increased in all groups, but significantly less in group I. The maximal MAP increase occurred at T1 and was 6.7 +/- 2.2% in group I, 27.9 +/- 4.9% in group II, and 27.1 +/- 6.5% in group III (difference between I and II-III: p <0.005). HR increased similarly in the three groups, but less in group I. The maximal CSFP increase occurred at T0.5 and was 12.2 +/- 10.0% in group I, 31.9 +/- 10.8% in group II, and 24.5 +/- 5.6% in group III (difference between I and II-III: p < -0.05). The changes in CPP paralleled MAP changes. In conclusion, the thiopentone-isoflurane sequence and continuous propofol anesthesia provide similar hemodynamic conditions and responses to nociceptive stimuli; local lidocaine infiltration achieves better control of MAP, HR, CSFP, and CPP after HH application than the deepening of general anesthesia or intravenous fentanyl.