Prevention of Intracranial Hypertension During Laryngoscopy and Endotracheal Intubation

Abstract

In nine patients, with preoperative ICP monitoring, anaesthesia was induced with thiopentone 5 mg kg-1 given over 1 min, followed by pancuronium 0.1 mg kg-1. After manual hyperventilation with nitrous oxide and oxygen for 3 min they were given thiopentone 2.5 mg kg-1 over 30 s (phase 1); 30 s later laryngoscopy was performed and topical analgesia administered to the larynx. Endotracheal intubation was performed 1 min after spraying the cords (phase 2). The measurements continued for a further 5 min during which the patients were mechanically ventilated (phase 3). ICP and intra-arterial pressure were recorded. Although there was a significant decrease (P less than 0.05) in MAP at the end of the second dose of thiopentone, there were no other significant changes in ICP, MAP or PaCO2 throughout the study. In two patients there were transient decreases in cerebral perfusion pressure to less than 60 mm Hg. Although MAP increased in five of the patients during laryngoscopy and intubation, there was no increase in ICP, showing that the MAP was still within the autoregulatory limits.

Effect of a Second Dose of Thiopentone on Haemodynamic Response to Laryngoscopy and Intubation

“…The mean arterial pressure in the second dose thiopentone group increased, following laryngoscopy and intubation, by only 18.7 mmHg from the preinduction value, compared with 23.7 mmHg increase in the control group. This is compatible with the findings of Unni (18) and Cowarker who used the second dose thiopentone at a dose of 2.5 mg/kg over 30 seconds before laryngoscopy.…”

La réponse de l’index bispectral à l’intubation endotrachéale est similaire chez les patients normotendus et hypertendus

“…Addition of induction agents 12 or inhalational anesthetics 13 are frequently used before tracheal intubation to blunt circulatory responses, but may deepen both the hypnotic and antinociceptive components of anesthesia. We found that normotensive and hypertensive patients showed similar increases in BIS after tracheal intubation, indicating that there was no difference in the intubation-induced arousal responses in these two groups of patients.…”