Ventriculo-arterial coupling detects occult RV dysfunction in chronic thromboembolic pulmonary vascular disease.

Chronic thromboembolic disease (CTED) is suboptimally defined by a mean pulmonary artery pressure (mPAP)  0.68 and Ees/Ea < 0.68 subgroups demonstrated constant RV stroke work but lower stroke volume (87.7 ± 22.1 vs. 60.1 ± 16.3 mL respectively, P = 0.006) and higher end-systolic pressure (36.7 ± 11.6 vs. 68.1 ± 16.7 mmHg respectively, P < 0.001). Lower Ees/Ea in CTED also correlated with reduced exercise ventilatory efficiency. Low Ees/Ea aligns with features of RV maladaptation in CTED both at rest and on exercise. Characterization of Ees/Ea in CTED may allow for better identification of occult RV dysfunction

Ultrasound-guided serratus plane block as an effective adjunct to systemic analgesia in four dogs undergoing thoracotomy

Background: Ultrasound-guided serratus plane block (UGSPB) is a loco-regional anesthesia technique designed to desensitize the thoracic wall. It is a compartmental block, where local anesthetic is delivered to the fascial, intermuscular plane. Since its original description in humans, two cadaveric veterinary studies, redefining the technique, have been performed. Taking into account the successful use of the UGSPB in human medicine, we employed the veterinary description to perform this block in four dogs undergoing thoracotomy. The case series described below aims to share our experience of the clinical application of this new loco-regional anesthesia technique in dogs. Case Description: Four dogs, with different underlying medical conditions underwent cranial lateral thoracotomy. The analgesia protocol consisted of intravenous methadone and UGSPB performed half an hour before the beginning of the procedure. The cardiovascular system was closely monitored for any signs of nociception. Fentanyl, although available as rescue analgesia, was not required in any of these cases as no signs of nociception were present. Conclusion: To the authors’ knowledge, this is the first veterinary clinical report using the UGSPB as a part of a multimodal analgesia protocol in dogs undergoing thoracotomy. Based on this observation, UGSPB has the potential to prevent nociception and reduce the intraoperative opioid requirements in dogs undergoing thoracotomy. A prospective randomized clinical trial is required to confirm these promising results

Dataset for: Ventriculo-Arterial Coupling Detects Occult RV Dysfunction in Chronic Thromboembolic Pulmonary Vascular Disease

Chronic thromboembolic disease (CTED) is sub-optimally defined by a mean pulmonary artery pressure (mPAP) < 25mmHg at rest in patients that remain symptomatic from chronic pulmonary artery thrombi. To improve identification of RV pathology in patients with thromboembolic obstruction, we hypothesized that the right ventricular (RV) ventriculo-arterial (Ees/Ea) coupling ratio at maximal stroke work (Ees/Eamax sw) derived from an animal model of pulmonary obstruction may be used to identify occult RV dysfunction (low Ees/Ea) or residual RV energetic reserve (high Ees/Ea). Eighteen open chested pigs had conductance catheter RV pressure-volume (PV)-loops recorded during PA snare to determine Ees/Eamax sw. This was then applied to ten patients with chronic thromboembolic pulmonary hypertension (CTEPH) and ten patients with CTED, also assessed by RV conductance catheter and cardiopulmonary exercise testing. All patients were then re-stratified by Ees/Ea. The animal model determined an Ees/Eamax sw = 0.68±0.23 threshold, either side of which cardiac output and RV stroke work fell. Two patients with CTED were identified with an Ees/Ea well below 0.68 suggesting occult RV dysfunction whilst three patients with CTEPH demonstrated Ees/Ea ≥ 0.68 suggesting residual RV energetic reserve. Ees/Ea > 0.68 and Ees/Ea < 0.68 sub-groups demonstrated constant RV stroke work but lower stroke volume (87.7±22.1 vs. 60.1±16.3mL respectively, p=0.006) and higher end-systolic pressure (36.7±11.6 vs. 68.1±16.7mmHg respectively, p<0.001). Lower Ees/Ea in CTED also correlated with reduced exercise ventilatory efficiency. Low Ees/Ea aligns with features of RV maladaptation in CTED both at rest and on exercise. Characterisation of Ees/Ea in CTED may allow for better identification of occult RV dysfunction