THE EFFECT OF SKULL-PIN INSERTION ON CEREBROSPINAL-FLUID PRESSURE ANDCEREBRAL PERFUSION-PRESSURE - INFLUENCE OF SUFENTANIL AND FENTANYL

This randomized prospective study measured the effects of an intraveno us opioid bolus on cerebrospinal fluid pressure (CSFP), mean arterial pressure (MAP), and cerebral perfusion pressure (CPP) during skull-pin insertion. Twenty-two adult patients scheduled for elective craniotom y for supratentorial lesions were studied. Outcome variables were MAP, heart rate (HR), and lumbar CSFP. The standardized anesthetic egimen included fentanyl (2 mu g/kg), thiopental (5-7 mg/kg), lidocaine (1.5 mg/kg), isoflurane (0.3-0.7 minimum alveolar anesthetic concentration) , and vecuronium (0.1 mg/kg). During stable anesthesia, sufentanil (0. 8 mu g/kg) or fentanyl (4.5 mu g/kg) was given as a bolus before skull -pin insertion. The hemodynamic effects of the opioid injection were m odified with phenylephrine and/or atropine when indicated. CSFP remain ed unchanged in both treatment groups. MAP and CPP increased approxima tely 10 mm Hg after skull-pin insertion (P<0.001). In the sufentanil g roup, HR decreased approximately 10 bpm after opioid injection and rem ained decreased throughout the study. In fentanyl-treated patients, HR decreased 8 bpm after opioid injection but returned to preopioid rate s after skull-pin insertion. In conclusion, in anesthetized patients, an intravenous bolus of fentanyl or sufentanil prior to skull-pin inse rtion results in stable values of CSFP, CPP, BP, and HR when the hemod ynamic effects of the opioid are modified with phenylephrine and atrop ine.