Determining the minimum number of endotracheal intubation cases necessary to develop the skills of medical students

  • Weerayutwattana R Department of Anesthesiology, Faculty of Medicine, Navamindradhiraj University, Bangkok
  • Teeratchanan T Department of Anesthesiology, Faculty of Medicine, Navamindradhiraj University, Bangkok
  • Poopipatpab S Department of Anesthesiology, Faculty of Medicine, Navamindradhiraj University, Bangkok
  • Supawattanabodee B Department of Research Methodology and Medical Innovation, Faculty of Medicine, Vajira Hospital, Navamindradhiraj University, Bangkok
Keywords: endotracheal intubation, learning curve, medical students, medical education research


Objectives  This study aimed to define the minimum number of cases necessary for 5th year medical students to develop endotracheal intubation skills during Anesthesiology Department training by means of the construction of a learning curve.

Methods In this longitudinal descriptive study, 5th year medical students performed endotracheal intubation (ETI) on live patients under the supervision of anesthesiologists. The number of intubation attempts and the results of those attempts were recorded. The generalized linear model (probit family) was used to construct the learning curve.  The secondary outcome was determination of the overall confidence of the students in their ETI skill at the end of the session as measured using a 4-point Likert scale.

Results  Data of seventy-four students was analyzed in this study. None of the students had had previous experience in ETI with a patient. The mean number of ETI attempts per student was 5.26 (SD 1.23, range 3-10). The probability of a successful ETI was 92.8% in the 3rd attempt and 100% in the 4th attempt. Self-reported levels of overall confidence in their ETI skills were as follows:  55 (74.3%) students would attempt ETI alone, 9 (12.2%) students were completely confident in their ability, 9 (12.2%) students would seek supervision, and 1 student (1.3%) was completely uncomfortable in doing the procedure.

Conclusions During their Anesthesiology Department rotation, medical students should be provided the opportunity to make at least 3 intubation attempts to achieve a 90% probability of a successful ETI.  The specific course syllabus should be designed for each individual institution.


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How to Cite
R W, T T, S P, B S. Determining the minimum number of endotracheal intubation cases necessary to develop the skills of medical students. Chiang Mai Med J. [nternet]. 2021Jul.1 [cited 2021Dec.5];60(3):317-23. vailable from:
Original Article