Comparison of blind intubation and a smartphone-based endoscope-assisted intubation in rabbits

Published:September 04, 2020DOI:



      To compare between blind and smartphone-based endoscope-assisted techniques for endotracheal intubation in rabbits.

      Study design

      Prospective clinical study.


      A total of 34 rabbits.


      Rabbits were assigned to four groups: intubation by a veterinary anesthesiologist (VA) or an exotic pet medicine specialist (EPS) using blind or endoscope-assisted techniques. Propofol dose, number of attempts until successful intubation, total time for intubation, duration of the successful attempt and occurrence of lingual cyanosis/laryngeal lesions were recorded. Data were analyzed by t test, Wilcoxon–Mann–Whitney U test or chi-square test. Pearson correlation for body weight was performed.


      The success rate of blind intubation was 88.9% and 77.8% for VA and EPS, respectively. Propofol dose, total and median number of attempts, total time for intubation and duration of the successful attempt were 3.1 (0–6.2) mg kg–1, 19, 2 (1–5), 79 ± 65 and 30 ± 20 seconds for VA and 1.5 (0–4.5) mg kg–1, 24, 3 (1–5), 136 ± 92 and 38 ± 16 seconds for EPS. The success rate of endoscope-assisted intubation was 87.5% for both operators. Propofol dose, total and median number of attempts, total time for intubation and duration of the successful attempt were 2.5 (1.3–7.4) mg kg–1, 22, 3 (1–5), 170 (65–368) and 46 (22–150) seconds for VA and 3.2 (0–6) mg kg–1, 11, 1 (1–4), 56 (27–432) and 55 (26–79) seconds for EPS. VA performed blind intubation more quickly, propofol dose was lower and cyanosis was less frequent than in the endoscope-assisted group.

      Conclusions and clinical relevance

      Both techniques were reliable for rabbit endotracheal intubation. Best results were achieved when the operator was experienced in the technique. The smartphone-based endoscope is a useful aid for rabbit intubation.


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