Retention of basic suturing skills with brief or extended practice in veterinary students.

OBJECTIVE: To evaluate the effect of practice duration on accuracy, retention, and confidence when learning how to tie basic surgical knots. STUDY DESIGN: Prospective study. SAMPLE POPULATION: Fifteen first-year veterinary students. METHODS: Students were randomly assigned to a 2-week practice (TWP) or an 8-week practice (EWP) to learn how to tie surgeon's, strangle, and miller's knots. Students' knot-tying accuracy and confidence were evaluated immediately after training, at an intermediate time point (2-6 weeks postpractice), and at 12 weeks postpractice. RESULTS: Students who had been trained during an extended period tied the strangle knot correctly more often at all assessments (P = .025). The ability of students trained for 2 weeks to tie the strangle knot correctly decreased over time (P = .028). These students lost some confidence (P = .03) and repositioned suture more frequently (P = .03) while constructing the strangle knot at the final time point compared with students trained for 8 weeks. Students who completed TWP felt more confident at placing surgeon's knots than friction knots at the final assessment period (P = .0164 miller's knot, P = .0056 strangle knot), whereas confidence did not differ between knot types for students who completed EWP. All students felt less confident with their knot-tying skills at 12 weeks postpractice. CONCLUSION: Training for 8 weeks rather than for 2 weeks resulted in superior knot tying skills. Students' confidence decreased 12 weeks after training. CLINICAL SIGNIFICANCE: Prolonged distributed practice is recommended to train students for more complex tasks such as placement of a strangle knot.

In vitro security of 3 surgical knots placed by novice veterinary students.

OBJECTIVE: To determine the most secure knot when tied by veterinary students in a ligation model. STUDY DESIGN: Prospective study. SAMPLE POPULATION: Sixteen first-year veterinary students. METHODS: Veterinary students were taught 3 knots: surgeon's, Miller's, and strangle. After having demonstrated competence, students tied each knot twice in a vascular ligation model at physiologic pressure. The system was tested for completeness of occlusion and volume of fluid lost over 10 seconds. Time, reattempts, repositioning, correctness, and difficulty score were documented. Students were surveyed before and after training regarding their experience. RESULTS: Students correctly tied 75% of all knots and achieved complete occlusion of the model with 56% of knots. No difference was identified among knot types in correctness, difficulty, complete occlusion, or time to construct the knot. The first surgeon's knot placed by students had more fluid loss than the Miller's knot, but this was not true of the second knot. CONCLUSION: Incomplete occlusion was common among all knot types, but students generally achieved similar knot security when placing surgeon's, Miller's, and strangle knots on a model. More surgeon's knots failed catastrophically during the first attempt, evidenced by a greater volume of fluid loss. CLINICAL SIGNIFICANCE: This study does not provide evidence to recommend any of the 3 tested knots as superior to the others to improve the security of ligatures during surgeries performed by students. The prevalence of incomplete occlusion among student knots illustrates the requirement for education regarding knot security and vigilant monitoring of students performing live animal surgeries.