Face validity of the pulsatile organ perfusion trainer for laparoscopic cholecystectomy.

BACKGROUND: The pulsatile organ perfusion (POP) trainer provides training of minimally invasive surgery (MIS) with real instruments and cadaveric organs. It provides training of full procedures with simulation of bleeding. Although widely used, the face validity has not yet been evaluated. This study aimed to establish face validity of the POP trainer for laparoscopic cholecystectomy (LC) and its usefulness compared with other training modalities. MATERIALS AND METHODS: During MIS courses, the participants (n = 52) used the POP trainer to perform LC. Face validity was assessed with questionnaires for realism and usefulness on a five-point Likert scale. Participants were divided into two groups: experts (n = 15) who had performed more than 50 laparoscopic procedures and novices (n = 37) with less than 50 procedures. Secondary aims included the ranking of training modalities, as well as exploration of their specific advantages and disadvantages. RESULTS: The POP trainer was found to be realistic (3.8 ± 0.9) and useful (4.6 ± 0.9). Differences between experts and novices were only found for "The training modality resembles reality" (3.1 ± 0.8 vs. 3.8 ± 0.7; p = 0.010), "The operation on the POP trainer is realistic" (3.4 ± 1.1 vs. 4.5 ± 0.8; p = 0.003), and "It would be desirable to have a POP trainer at my own hospital" (4.2 ± 1.1 vs. 4.8 ± 0.8; p = 0.040). In the ranking, the animal training (1.1 ± 0.3) placed first, the POP trainer (2.3 ± 0.9) second, and the VR trainer (2.8 ± 0.9) and box trainer (2.8 ± 1.1) third. The realistic simulation of animal training was named as an advantage most often, while the unrealistic simulation of the VR trainer was the most often named disadvantage. CONCLUSIONS: The POP trainer was rated a highly realistic and useful training modality with face validity for LC. Differences between experts and novices existed concerning realism and desirability. Future studies should evaluate the POP trainer for more advanced surgical procedures. The POP trainer widens the spectrum of modalities for training of MIS in a safe environment outside the operating room.

Improved reflux monitoring in the acute gastroesophageal reflux porcine model using esophageal multichannel intraluminal impedance measurement.

BACKGROUND: Acute animal models are needed to obtain further insights into the mechanism of gastroesophageal reflux disease. Existing acute models use imprecise methods to detect reflux. The aim of the present study was to evaluate the potential of esophageal multichannel intraluminal impedance measurement (MII) to improve the quality of results of acute reflux porcine models. MATERIALS AND METHODS: MII was used in ten pigs to monitor gastroesophageal reflux. Measurements were obtained (A) before and (B) after mobilization of the esophagus and (C) after myotomy. The results were compared to those obtained when reflux was monitored by esophageal drainage of intragastrically infused blue solution (DBS). RESULTS: The times to first appearance of reflux were 67% (A), 86% (B), and 57% (C) of those by DBS when detected by MII; p < 0.05. The respective values for intragastric pressures needed to provoke reflux were 46%, 76%, and 66%; p < 0.05. Although the lower esophageal sphincter pressure decreased by 69% after (B) the intragastric pressure needed to provoke reflux increased by 140%; p < 0.05. CONCLUSIONS: MII improves the detection of reflux in the acute reflux porcine model. The finding that after sole mobilization of the esophagus the intragastric pressure needed to provoke reflux was increased although the finding that the pressure of the lower esophageal sphincter was decreased needs further investigation.