[Suppression of blood pressure increases during intubation: lidocaine or fentanyl?]

The hypertensive response to anesthetic induction with endotracheal intubation may be harmful in patients with cardiovascular disease, increased intracranial pressure, or anomalies of the cerebral vessels. Recommendations for attenuating the reflex hypertension and tachycardia elicited by upper airway irritation are therefore manifold. Besides minimizing the cardiovascular response, anesthesia induction for patients at risk must also satisfy the following requirements: it must be applicable regardless of patient collaboration, prevent impairment of cerebral blood flow, and avoid arousal of the patient; it should neither be time-consuming nor affect the duration or modality of the ensuing anesthesia. Among the recommended procedures, intravenous lidocaine or fentanyl appear to best fulfill the above mentioned criteria. However, our own equivocal observations and controversial results in the literature concerning the efficacy of intravenous lidocaine prompted us to reinvestigate the issue in two well-defined patient groups. In 46 patients with intracranial vessel malformations and 78 patients with brain tumors, blood pressure responses to endotracheal intubation were studied under anesthesia induction with 1.5 mg/kg lidocaine or 6 micrograms/kg fentanyl i.v. 30 s before thiopental injection or 2-3 min before intubation. The two equally simple induction procedures were compared to anesthesia induction with thiopental alone. In both patient groups no significant effect of lidocaine on the pressure response could be observed. Fentanyl lowered the pressure response slightly though significantly in brain-tumor patients only (p less than 0.05), but showed a significant pressure-lowering action persisting over the whole observation period in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)