Background and goal. The major upper abdominal interventions are associated with a high risk and incidence of postoperative pulmonary complications (PPC) that can be recognized with lung ultrasound (LUS). The goal of this study was to assess the predictive value of perioperative LUS for PPC including transient hypoxemia and atelectases after major open pancreatoduodenal surgery.
Methods.Thirty-three adult patients scheduled for elective pancreatoduodenal interventions were enrolled into a single-centre ongoing prospective study. All patients were ventilated with protective parameters: VT 6 ml/kg and PEEP 5 cm H2O. The LUS studies were conducted preoperatively and at 24 hrs after the surgery with a summarized assessment of consolidations and pulmonary oedema in three standard points on both sides of the chest. Plain chest radiogram was performed at 24 hrs postoperatively. Cardiopulmonary and respiratory parameters were registered during surgery and up to 48 hrs of the postoperative period. The statistical analysis was performed using Mann–Whitney U-test, Wilcoxon’s test and ROC-analysis. Data are presented as median (25th–75th percentiles). p values < 0.05 were regarded as statistically significant.
Results. We found strong-to-moderate correlations between pre- and postoperative LUS scores for both consolidations (rho = 0.83 p < 0.001), and the number of B-lines (rho = 0.55; p = 0.007). The total degree of LUS consolidations in pre- and postoperative periods correlated only with PaO2/FiO2 ratio at 48 hours after intervention (rho = –0.37, p = 0.04; rho = –0.46, p = 0.008, respectively). We revealed the inadequate predictive role of the preoperative LUS consolidation score for to the hypoxemic events (PaO2/FiO2 < 300 mm Hg) at 48 hours after intervention (AUC 0.71, specificity 100%, sensitivity 30%), while the 24 hrs postoperative LUS score allowed a reliable prognosis for delayed hypoxemia at 48 hrs with AUC 0.79, specificity 82% and sensitivity 70%.
Conclusion. The perioperative LUS in open pancreatoduodenal surgery is a reliable and specific technique both to diagnose PPC including atelectases and to predict the delayed postoperative hypoxemia. Further studies are warranted to assess a clinical rationale to use the postoperative LUS as one from the “fit for ICU discharge” criteria.

Acknowledgements: The authors appreciate the valuable assistance of Dr. Tatyana V. Kachalova and Nadezhda S. Metelyova.


03 / Prognostic value of perioperative lung ultrasound for postoperative pulmonary complications after major upper abdominal interventions