Cardiovascular responses to tracheal extubation or LMA removal in normotensive and hypertensive patients.

Objective: This study was undertaken to evaluate the haemodynamic changes of tracheal extubation or removal of a laryngeal mask airway (LMA) in normotensive and hypertensive patients.

Methods: In a randomized trial of normotensive and hypertensive patients (n = 40 of each), tracheal extubation or LMA removal was performed. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and 1, 2, 3, 5, and 10 min after tracheal extubation or LMA removal.

Results: In normotensive patients, HR, MAP and RPP increased following tracheal extubation or LMA removal, and remained elevated for a maximum three minutes (P < 0.05). In hypertensive patients, the haemodynamic increases in response to extubation or LMA removal were observed for up to five minutes (P < 0.05). The immediate cardiovascular responses to extubation were greater than those related to LMA removal in both normotensive and hypertensive patients (normotensive: HR; 95 +/- 14 vs 81 +/- 11, MAP; 124 +/- 18 vs 106 +/- 10, RPP; 14,951 +/- 2720 vs 10,654 +/- 1898, hypertensive: HR 105 +/- 10 vs 87 +/- 13, MAP; 146 +/- 17 vs 119 +/- 12, RPP; 20,492 +/- 1674 vs 12,862 +/- 2115, mean +/- SD, P < 0.05). Following extubation or LMA removal, these haemodynamic variables increased more markedly in hypertensive patients than in normotensive patients (P < 0.05).

Conclusions: Removal of LMA is associated with less cardiovascular change than tracheal extubation in both normotensive and hypertensive patients.