Development of Bronchoconstriction After Administration of Muscle Relaxants in Rabbits with Normal or Hyperreactive Airways

Abstract

Neuromuscular blocking drugs can induce intraoperative bronchospasm. We characterized the magnitude and the temporal profile of the constriction in normal or in hyperresponsive airways after injections of neuromuscular blocking drugs. Respiratory system impedance (Zrs) was measured continuously over a 90-s apneic period in naïve and rabbits sensitized to allergens by ovalbumin. Fifteen s after the start of Zrs recordings, succinylcholine, mivacurium, or pipecuronium was administered in random order. Zrs was then also recorded during the administration of increasing doses of exogenous histamine. To monitor the changes in the airway mechanics during these maneuvers, Zrs was averaged for 2-s time windows, and the airway resistance (Raw) was determined by model fitting. The increases in Raw were significantly larger in the sensitized rabbits than in the naïve animals. The largest increases in Raw and the maximum rate of change in Raw were obtained for succinylcholine (146% +/- 29% and 0.80 +/- 0.12 cm H2O/L, respectively) and mivacurium (80% +/- 25% and 0.71 +/- 0.13 cm H2O/L) and the smallest were obtained for pipecuronium (40% +/- 12% and 0.41 +/- 0.04 cm H2O/L). Allergic sensitization leads to severe and rapidly developing bronchospasm after administrations of mivacurium or succinylcholine. These deleterious side effects should be considered when succinylcholine or mivacurium is administered in the presence of bronchial hyperreactivity.

Sevoflurane and desflurane protect cholinergic-induced bronchoconstriction of hyperreactive airways in rabbits

“…25,26 Independently of the anesthetic management, the presence of airway hyperresponsiveness to MCh that mimics cholinergic stimuli was confirmed in the present study. Additionally, consistent with previous results, all animals in the present study exhibited a response to OVA, with marked increases in all resistive mechanical parameters, confirming that the allergic sensitization was the major cause of BHR.…”

Lack of desensitization of the cough reflex in ovalbumin-sensitized rabbits during exercise

“…The month before the acute experiment with tracheal stimulations and exercise, an OVA sensitization protocol was performed. As previously described, OVA sensitized rabbits [ 11 , 12 ] received intra-peritoneal (i.p.) injections of 0.1 mg OVA and 10 mg Al(OH) 3 dissolved in 1 ml saline (0.9%) on day 1 and day 14.…”

Lung mechanical and vascular changes during positive- and negative-pressure lung inflations: importance of reference pressures in the pulmonary vasculature

“…Lung mechanics. The respective contributions of the airway and tissue mechanical properties to the total lung resistance were estimated by the modified forced oscillation technique, which allows continuous assessment of the mechanical impedance of the isolated lungs (ZL), as described in detail previously (10,18). During impedance recordings, a loudspeaker-in-box system generated a smallamplitude pseudorandom signal with frequency components between 0.5 and 19 Hz through a 100-cm-long, 2-mm-ID polyethylene catheter serving as a wave tube.…”