STRESS-RESPONSE TO TRACHEAL INTUBATION - DIRECT LARYNGOSCOPY COMPAREDWITH BLIND ORAL INTUBATION

Haemodynamic and hormonal responses to tracheal intubation can be prof ound and associated with serious cardiovascular and cerebral side effe cts. The Augustine Guide, a device enabling blind oral intubation, has been introduced recently. The aim of our study was to compare the hae modynamic and hormonal stress response of this method with direct lary ngoscopy. Thirty five patients (ASA 1 and 2) were randomly assigned to undergo either direct laryngoscopy (n = 17), or blind oval intubation (n = 18). Haemodynamic responses and concentrations of adrenaline, no radrenaline and prolactin were determined prior to induction, before i ntubation and 5 min after intubation. The median duration of intubatio n was 22s for direct laryngoscopy vs 46 s for blind oval intubation (p < 0.05). Between the groups, no significant differences were observed for heart rate, systolic or mean arterial blood pressure. Serum level s of adrenaline decreased slightly after induction and remained unalte red after intubation in both groups. Noradrenaline (1.01 vs 0.66 nmol. l(-1)) and prolactin (5.2 vs 2.9nmol.l(-1)) levels were significantly higher after direct laryngoscopy compared to blind oral intubation. Al though blind oral intubation took significantly longer to perform than direct laryngoscopy, hormonal stress response was less pronounced. Bl ind oral intubation should therefore not be withheld from patients wit h impaired cardiovascular reserve.