Objectives: To compare the preventive effects of esmolol and lidocaine on the increase in mean arterial pressure (MAP) and intracranial pressure (ICP) during endotracheal intubation in neurosurgery.
Study design: Comparative, randomised, double-blind study.
Patients: Twenty-two patients, physical status ASA I or II, undergoing neurosurgery, and randomised into two groups (esmolol group and lidocaine group).
Methods: After induction of anaesthesia with thiopentone, vecuronium, fentanyl and isoflurane, one group received iv esmolol 1.5 mg.kg-1 and the other iv lidocaine 1.5 mg.kg-1, 130 sec before endotracheal intubation. The MAP measured with a radial catheter, the ICP obtained with a lumbar subarachnoid catheter and the cerebral perfusion pressure (CPP, calculated from MAP and ICP) were assessed before induction of anaesthesia, before esmolol or lidocaine injection, and before intubation, during the maximal change in MAP, as well as 2 and 5 minutes after intubation.
Results: The time course of MAP, ICP and CCP were similar throughout the study in the two groups, with a significant decrease (P < 0.05) of the CPP from 92 +/- 12 to 62 +/- 8 mmHg after esmolol, and from 96 +/- 12 to 68 +/- 15 mmHg after lidocaine. Following intubation, CPP increased significantly (P < 0.05) to 99 +/- 23 mmHg after esmolol and to 99 +/- 17 mmHg after lidocaine. The ICP increased also significantly (P < 0.05) after intubation from 11 +/- 6 to 17 +/- 10 mmHg in the esmolol group, and from 10 +/- 6 to 16 +/- 9 mmHg in the lidocaine group.
Conclusions: Esmolol or lidocaine as an iv bolus of 1.5 mg.kg-1 before laryngoscopy and intubation do not completely prevent the increase in MAP and ICP.