RESUMO
Video-assisted thoracoscopy (VATS) cardiac surgery requires one-lung ventilation (OLV) and transoesophageal ultrasound (TOE) monitoring. Colour and spectral Doppler make it possible to study the pattern of blood flow in the pulmonary vessels within the atelectatic lung. In this case report we describe how TOE can be used to detect blood flow within the atelectatic lung and to assess pulmonary vascular resistance (PVR) and right ventricular (RV) afterload. FINDINGS: Three anaesthetised, mechanically ventilated adults scheduled for cardiac surgery by VATS were scanned with TOE. After left OLV, the transducer was rotated away from the heart to obtain 2D colour Doppler images of blood flow within the consolidated lung parenchyma. We were able to identify the flow pattern of the intrapulmonary branches of the pulmonary artery. PVR was recorded using pulsed cardiac Doppler at baseline, after induction of general anaesthesia, 20 min after OLV and at the end of OLV, and after performing an alveolar recruitment manoeuvre (ARM) that led to complete resolution of the aforementioned consolidation. CONCLUSIONS: TOE is a semi-invasive imaging tool that can be used to diagnose and study PVR-induced atelectasis and to analyse the resulting pulmonary shunt and its possible effect on PVR.