Introduction Lung ultrasonography has been proposed as a useful method for diagnosing alveolar-interstitial syndrome, based on the detection and quantification of comet-tail artefacts. The aim of the present study was to investigate its value in the diagnosis of respiratory dysfunction and severity stratification in patients with acute pancreatitis (AP).
Method This prospective pilot study received ethical committee approval, and written informed consent was obtained from all participants or their surrogates. Between September and December 2013, 41 patients (median age: 59.1 years; 21 males) presenting to the Royal Infirmary of Edinburgh with a potential diagnosis of AP were recruited. Each participant underwent lung ultrasonography and the number of comet-tail artefacts was linked with contemporaneous, prospectively collected clinical data. Patient group comparisons, areas under the curve (AUC) and respective measures of diagnostic accuracy were examined in relation to: i. Respiratory dysfunction status, ii. Disease severity, as defined by the revised Atlanta criteria for AP, iii. C-Reactive Protein contemporaneous with the scan, and iv. Maximum CRP value of the first week of admission. The results were analysed for all lung quadrants, all quadrants except for the lower lateral, and upper quadrants alone.
Results A greater number of comet tails were evident in patients with respiratory dysfunction, those with severe disease and when contemporaneous and maximum CRP were above 100 mg/L (P = 0.021; P < 0.001; P = 0.048 and P = 0.003, respectively). The AUC was greater for the method examining upper lung quadrants alone, when respiratory dysfunction and severity were used as the parameter of interest (AUC = 0.783, 95% C. I.: 0.544–0.962, and AUC = 0.996, 95% C. I.: 0.982–1.000, respectively). Conversely, examining all lung quadrants except for the lower lateral provided the best results for contemporaneous and maximum CRP (AUC = 0.708, 95% C. I.: 0.510–0.883, and AUC = 0.800, 95% C. I.: 0.640–0.929).
Conclusion Ultrasonography of non-dependant lung parenchyma can reliably detect evolving respiratory dysfunction in acute pancreatitis and is potentially useful for severity stratification. This simple, easily repeatable bedside test deserves further validation in a larger cohort.
Disclosure of interest None Declared.