Pulmonary complications in canine acute pancreatitis: a pilot study

In human beings, acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) in acute pancreatitis (AP) represents important complications with a high mortality rate (30-40%). To our knowledge, there are no clinical veterinary studies on this topic. The aim of the present study is to evaluate pulmonary complications during canine AP and their association with the outcome. AP diagnosis was made if there were compatible clinical signs and laboratory parameters, abnor- mal SNAP cPL test and a positive abdominal ultrasound within 48 hours from the admission. Thoracic radiography was performed for each patient using a digital radiological equipment and subgraded base on the pulmonary pattern (normal, interstitial or alveolar). At the admission, arterial blood samples, obtained from the dorsal pedal artery, at room air (FiO2=21%), were analyzed (ABL 700 series, Radi- ometer, Denmark). ALI/ARDS were diagnosed using the current veter- inary consensus: (1) acute onset (<72 hours) of respiratory distress (RD) (tachypnea and laboured breathing at rest), (2) known risk factors, (3) evidence of pulmonary capillary leak without cardiac disease and (4) evidence of inefficient gas exchange. Dogs were divided into 2 groups according to outcome at 15 days from their admission: survi- vors and non-survivors. Normal distribution was assessed using D’Agostino-Pearson test. Welch’s t-test was used to compare PaCO2, P[A−a]O2 gradient with the outcome; meanwhile, pH, PaO2, PaO2/ FiO2 were compared to the outcome using Mann-Whitney U-test. Exact tests were used to compare the presence of radiographic abnor- malities, RD and ALI/ARDS to the outcome. Odds ratio (OR) was cal- culated. Twenty-three client-owned dogs with owners’ consent, admitted to the Veterinary Teaching Hospital, were prospectively enrolled. Ten dogs (43%) died during the study period. Two out of 10 dogs were euthanized due to poor prognosis or to progressive dis- ease. Ten out of 23 dogs showed RD which was associated with poor outcome (p=0.0001; OR 108 95% CI 7-1225). Nineteen dogs (83%) showed radiographic alterations (10 alveolar pattern and 9 interstitial pattern) and they were associated to death (p=0.04). Non-survivors showed a lower PaCO2 levels than survivors (p=0.009). P[A−a]O2 gra- dient, pH, PaO2 and PaO2/FiO2 were similar between groups. ALI was diagnosed in seven dogs (30%) and no dogs had ARDS. The pres- ence of ALI was associated with poor outcome (p=0.0005). In dogs with AP, pulmonary complications seemed to be frequent and associ- ated with risk of death. Moreover, ALI/ARDS may be a severe pulmo- nary complication affecting the prognosis, as well as in human medicine.