Variation among trainee surgeons in interpreting diagnostic peritoneal lavage fluid in blunt abdominal trauma

Diagnostic peritoneal lavage is useful in selected patients who have sustained blunt abdominal trauma. The way in which 50 trainee surgeons (37 registrars and 13 senior registrars) perform and interpret diagnostic peritoneal lavage was investigated in this study by a simple questionnaire followed by assessment of simulated lavage fluid. This exposed misconceptions about interpretation of diagnostic peritoneal lavage fluid and a reliance upon visual assessment. Assessment of the simulated lavage fluid revealed a wide range of thresholds for a positive result (2460-48,700 red blood cells/mm3), although 49 surgeons (98%) had lower thresholds than that generally recommended. Senior registrars had significantly higher thresholds than registrars, implying a learning curve involving unnecessary laparotomies. In order to avoid this situation and to detect injuries that might otherwise be missed, trainee surgeons are recommended to perform cell count analysis routinely on diagnostic peritoneal lavage fluid.