A comparison between the V-gel supra-glottic airway mask and the commonly used cuffed endotracheal tube in spontaneous breathing cats under isoflurane anesthesia.

Abstract

This randomized clinical study compares the use of the endotracheal tube (golden standard) with the new laryngeal mask, the V-gel, in spontaneous breathing cats under isoflurane anesthesia, in respect to isoflurane leakage, ease of use and irritation of the upper respiratory system after surgery. Material/Methods: All cats were admitted for spaying or castration and were classified as ASA-1 or ASA-2 patient. Ten cats in the V-gel group and eleven cats in the ET-group. The cats premedicated with 20 µg/kg of dexmedetomidine and 15 µg/kg buprenorphine IM. Induction started with propofol, dosed to effect. For analgesic purposes the cats received 0.2 mg/kg metacam before surgery and 0.05mg/kg/day metacam per os by their owners, the first four days following surgery. The following variables were measured: -Required dose of propofol necessary for intubation or placing the V-gel; -Time between induction and recording of a first capnogram in seconds; -Detection of leakage of isoflurane to the environment measured with the Miran 205B Type Saphiree 100 isoflurane analizer; -Post-operative discomfort of the upper respiratory system, subjectively scored by the researcher during the recovery. -Post-operative discomfort of the upper respiratory system, subjectively scored with the owner 24 hours after surgery, by means of a questionnaire. The variables were tested by the Student-T-test and the discomfort was being tested by the Chi-Square test. The level of significance was set to P<0.05. Results: There was no significant difference when comparing the required dose propofol, ET-group (8.29±2.37mg) and V-gel group (6.61±2.93mg). There was a significant difference regarding the time between induction and first reading on the capnometer. Where the V-gel group had a shorter induction time (52.59±30.47sec.) compared to the ET-group (117. 27±27.47sec.). Both groups showed some leakage of the isoflurane, V-gel group (9.89±10.47 mg/m3) and ET-group (9.65±15.09 mg/m3), but no significant difference was found. During recovery six cats from the ET-group were found with an upper airway stridor. According to the Chi-Square test, there were statistically significant fewer cats with an upper airway stridor in the V-gel group (Chi-Square test=7.636364; p=0.005720; df=1).The discomfort scored by the owners showed no significant difference between both groups. Conclusion: The V-gel is easy to use and a good alternative for endotracheal intubation in spontaneous breathing cats under isoflurane anesthesia.