Bronchotracheal Stenting Management by Rigid Bronchoscopy under Extracorporeal Membrane Oxygenation (ECMO) Support: 10 Years of Experience in a Tertiary Center.

Purpose: Airway stenting offers good palliation and improves the quality of life in patients with inoperable bronchotracheal stenosis. However, in some cases, the management of stenting can be life-threatening. Hence, a strategy for maintaining oxygenation and hemodynamic stability should be anticipated to avoid critical situations. Herein, we report the use of extracorporeal membrane oxygenation (ECMO) in bronchotracheal stenting management to secure oxygenation and facilitate interventions. Methods: We retrospectively reviewed all patients who underwent rigid bronchoscopy under ECMO support for the management of bronchotracheal stenting at CHU UCL Namur hospital (Belgium), between January 2009 and December 2019. Results: We included 14 bronchoscopy cases performed on 11 patients (3 patients underwent 2 bronchoscopies) in this study; 12 were performed on males and 2 on females. The median age was 54 years. There were 11 benign and 3 malignant etiologies for the central airway obstruction/stenosis. Eight cases were supported by venovenous ECMO and six by venoarterial ECMO. The median ECMO time was 267 minutes. The weaning of ECMO support was successful in all cases. In most cases, the procedures were performed effectively and safely. Only two local complications caused by the cannulation of ECMO were reported, and anticoagulation was adapted to avoid bleeding at the operating site and clot formation in the system. Conclusion: Elective ECMO support was helpful and safe for the high-risk management of bronchotracheal stenting with rigid bronchoscopy and was not associated with any additional significant complications.

Do coronary bypass graft flows differ between on-pump and off-pump operations?

BACKGROUND: The aim of this study is to compare hemodynamic factors in coronary bypass grafts on-pump and off-pump. METHODS: Two propensity score-matched groups of 89 patients each including 408 dual beam Doppler flow measurements were compared. The study included only patent and single terminolateral bypass grafts. RESULTS: Flow was 64.9 +/- 37.3 mL/min in the on-pump group versus 58.6 +/- 35.0 mL/min in the off-pump group (p = 0.063); velocity was 23.8 +/- 10.5 versus 20.5 +/- 10.4 cm/s (p = 0.004); resistance measured as mm Hg/(mL/min(-1)) was 1.50 +/- 1.09 versus 1.76 +/- 1.14 (p = 0.020); pulsatility index was 1.98 +/- 1.52 versus 2.44 +/- 1.62 (p = 0.004). The hematocrit was 23.5 +/- 3.8% in the on-pump and 32.9 +/- 4.1% in the off-pump groups (p < 0 0.001). Multivariate analysis showed that hematocrit was the most significant factor influencing flow (p < 0.001) and velocity (p < 0.001), along with resistance (p = 0.004) and pulsatility index (p < 0.001). In a subset of 50 hemodynamic measurements made on left internal thoracic arteries implanted onto left anterior descending arteries and matched for hematocrit, there were no differences between on-pump and off-pump groups regarding flow, velocity, resistance, or pulsatility index. CONCLUSIONS: Off-pump compared with on-pump bypass surgery is associated with lower velocity and higher resistance in the grafts, mainly caused by changes in hematocrit and viscosity related to hemodilution.

Continuous cold blood cardioplegia improves myocardial protection: a prospective randomized study.

BACKGROUND: To assess the influence on myocardial protection of the rate of infusion (continuous vs intermittent) of cold blood cardioplegia administered retrogradely during prolonged aortic cross-clamping. The end-points were ventricular performance and biochemical markers of ischemia. METHODS: Seventy patients undergoing myocardial revascularization for three-vessel disease were prospectively randomized to receive intermittent or continuous retrograde cold blood cardioplegia. Hemodynamic measurements were obtained using a rapid-response thermodilution catheter and included right ventricular ejection fraction, cardiac output, left and right ventricular stroke work index, and systemic and pulmonary vascular resistance. Blood samples were obtained from the coronary sinus before cross-clamp application and immediately after cross-clamp removal for determinations of lactate and hypoxanthine. RESULTS: The left ventricular stroke work index trend was significantly superior (p = 0.038) by repeated-measures analysis in continuous cardioplegia. Other hemodynamic measurements revealed a similar trend. The need for postoperative inotropic drugs support was reduced in continuous cardioplegia. The release of lactate in the coronary sinus after unclamping was 2.30 +/- 0.12 mmol/L after intermittent cardioplegia and 1.97 +/- 0.09 mmol/L after continuous cardioplegia (p = 0.036). The release of hypoxanthine was 20.47 +/- 2.74 micromol/L in intermittent cardioplegia and 11.77 +/- 0.69 micromol/L in continuous cardioplegia (p = 0.002). CONCLUSIONS: Continuous cold blood cardioplegia results in improved ventricular performance and reduced myocardial ischemia in comparison with intermittent administration.