Usage of Laryngeal Mask Airway Devices in Veterinary Medicine

Abstract

Providing a secure airway management during general anesthesia could be problematic in some medical cases, especially when there is a risk of regurgitation and aspiration of the gastric content due to increased intragastric pressure. The current study aimed to test the applicability of two types of LMA in several animal species and to compare its effectiveness to the endotracheal intubation method in securing sealed airway respiration as an alternative to using endotracheal tubes. The study was conducted in dogs (n=33), cats (n=9), swine (n=9), rabbits (n=5), sheep (n=7) and roe deer (n=1). One or both types of laryngeal masks were used for each animal species: LMA Classic™-cLMA and LMA ProSeal™-PLMA. The assessment of each laryngeal mask was performed by determining the insertion technique, the possibilities of first-attempt insertion and malposition, the compliance with various animal species, ventilation time, cuff pressure, and sealing capacity. The highest LMA size compatility in dogs (23,87±14,30 kg) was size-3 in six and size-4 in forteen subjects; In swine (43,22±12,32 kg), size-4; In rabbits (3,84±0,36 kg) size-1; and in sheep (48,29±4,65 kg) size-3 and size-4. Ventilation time was highest in swine and roe deer (121,11±42,85 min and 300,00 min, respectively) and lowest in cat (28,33±16,96 min). First-attempt LMA insertion success was lowest in rabbits (60%), and highest in sheep and roe deer (100%). Malposition was with highest rate in rabbits (40%) and lowest in cat, sheep and roe deer (0%). Gastric reflux was most frequently observed in sheep (71,4%) and roe deer (100%). The usage of LMA in the veterinary anesthetic practice significantly improves airway management in animals during general anesthesia. The inflated LMA cuff does not prevent its disposition. Therefore, both the drain and respiratory tubes must be fixed. The usage of LMA in rabbits was associated with higher incidence of malposition and other complications. Our findings suggest that LMA designed for humans can be used for airway management in veterinary medicine.