BACKGROUND: The placement of cranial pins into the periosteum is a acute noxious stimulation during intracranial surgery, which can result in sudden increases in blood pressure and heart rate, causing increases in intracranial pressure and other hemodynamic responses. We compared blood pressures and heart rates after injecting fentanyl and esmolol or thiopental sodium and esmolol to blunt hypertensive response.

METHODS: Forty patients scheduled for a craniotomy were randomly divided into two groups: Intravenous (I.V.) bolus of fentanyl and esmolol group (n = 20) and the thiopental sodium and esmolol group (n = 20). After inducing general anesthesia with sevoflurane, nitrous oxide 50% and oxygen, an IV. bolus of either fentanyl and esmolol or thiopental sodium and esmolol was administered 2 minutes prior to the insertion of the cranial pin. Hemodynamic variables (systolic, diastolic, mean arterial pressure, and heart rate) were measured at 6 different time points; at baseline (drug administration), just before pinning, and at 30 seconds, and 1, 2, and 3 min after pinning.

RESULTS: The fentanyl and esmolol group showed lower blood pressure and heart rate increases than the thiopental sodium and esmolol group at 30 sec and 1 min after cranial pin insertion compared with just before pinning.

CONCLUSIONS: We conclude that I.V. fentanyl and esmolol 2 minutes prior to cranial pinning is more effective than I.V. thiopental sodium and esmolol at reducing blood pressure and heart rateincreases after cranial pinning.