Effect of tidal volume on extravascular lung water content during one-lung ventilation for video-assisted thoracoscopic surgery: a randomised, controlled trial.

BACKGROUND: The use of low tidal volume during one-lung ventilation (OLV) has been shown to attenuate the incidence of acute lung injury after thoracic surgery. OBJECTIVE: To test the effect of tidal volume during OLV for video-assisted thoracoscopic surgery on the extravascular lung water content index (EVLWI). DESIGN: A randomised, double-blind, controlled study. SETTING: Single university hospital. PARTICIPANTS: Thirty-nine patients scheduled for elective video-assisted thoracoscopic surgery. INTERVENTIONS: Patients were randomly assigned to one of three groups (n = 13 per group) to ventilate the dependent lung with a tidal volume of 4, 6 or 8 ml  kg(-1) predicted body weight with I:E ratio of 1:2.5 and PEEP of 5 cm H2O. MAIN OUTCOME MEASURES: The primary outcomes were perioperative changes in EVLWI and EVLWI to intrathoracic blood volume index (ITBVI) ratio. Secondary outcomes included haemodynamics, oxygenation indices, incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity and 30-day mortality. RESULTS: A tidal volume of 4 compared with 6 and 8 ml  kg(-1) after 45 min of OLV resulted in an EVLWI of 4.1 [95% confidence interval (CI) 3.5 to 4.7] compared with 7.7 (95% CI 6.7 to 8.6) and 8.6 (95% CI 7.5 to 9.7) ml  kg(-1), respectively (P < 0.003). EVLWI/ITBVI ratios were 0.57 (95% CI 0.46 to 0.68) compared with 0.90 (95% CI 0.75 to 1.05) and 1.00 (95% CI 0.80 to 1.21), respectively (P < 0.05). The incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity, hospitalisation and 30-day mortality were similar in the three groups. CONCLUSION: The use of a tidal volume of 4 ml kg during OLV was associated with less lung water content than with larger tidal volumes of 6 to 8 ml kg(-1), although no patient developed acute lung injury. Further studies are required to address the usefulness of EVLWI as a marker for the development of postoperative acute lung injury after the use of a low tidal volume during OLV in patients undergoing pulmonary resection. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01762709.

Right ventricular function during one-lung ventilation: effects of pressure-controlled and volume-controlled ventilation.

OBJECTIVES: To test the effects of pressure-controlled (PCV) and volume-controlled (VCV) ventilation during one-lung ventilation (OLV) for thoracic surgery on right ventricular (RV) function. DESIGN: A prospective, randomized, double-blind, controlled, crossover study. SETTING: A single university hospital. PARTICIPANTS: Fourteen pairs of consecutive patients scheduled for elective thoracotomy. INTERVENTIONS: Patients were assigned randomly to ventilate the dependent lung with PCV or VCV mode, each in a randomized crossover order using tidal volume of 6 mL/kg, I: E ratio 1: 2.5, positive end-expiratory pressure (PEEP) of 5 cm H2O and respiratory rate adjusted to maintain normocapnia. MEASUREMENTS AND MAIN RESULTS: Intraoperative changes in RV function (systolic and early diastolic tricuspid annular velocity (TAV), end-systolic volume (ESV), end-diastolic volume (EDV) and fractional area changes (FAC)), airway pressures, compliance and oxygenation index were recorded. The use of PCV during OLV resulted in faster systolic (10.1±2.39 vs. 5.8±1.67 cm/s, respectively), diastolic TAV (9.2±1.99 vs. 4.6±1.42 cm/s, respectively) (p<0.001) and compliance and lower ESV, EDV and airway pressures (p<0.05) than during the use of VCV. Oxygenation indices were similar during the use of VCV and PCV. CONCLUSIONS: The use of PCV offers more improved RV function than the use of VCV during OLV for open thoracotomy. These results apply specifically to younger patients with good ventricular and pulmonary functions.

Comparative study of the non-dependent continuous positive pressure ventilation and high-frequency positive-pressure ventilation during one-lung ventilation for video-assisted thoracoscopic surgery.

The application of volume controlled high-frequency positive-pressure ventilation (HFPPV) to the non-dependent lung (NL) may have comparable effects to continuous positive-airway pressure (CPAP) on the surgical conditions during one-lung ventilation (OLV) for video-assisted thoracoscopic surgery (VATS). After local Ethics Committee approval and informed consent, we randomly allocated 30 patients scheduled for elective VATS after the first 15 min of OLV to ventilate the NL with CPAP of 2 cm H(2)O (NL-CPAP(2)) and HFPPV using tidal volume 2 ml/kg, inspiratory to expiratory ratio <0.3 and respiratory rate 60/min (NL-HFPPV) for 30 min, each in a randomized crossover order. Intraoperative adequacy of surgical conditions was evaluated using a visual analog scale and the changes in hemodynamic and arterial oxygen were recorded. The application of NL-CPAP(2) and NL-HFPPV resulted in more improved arterial oxygenation than during OLV for VATS (P<0.001). The operative field was much better during the application of NL-CPAP(2) than during NL-HFPPV (P<0.001). We concluded that the application of CPAP to the NL during OLV offers good quality of operative field and improved arterial oxygenation for VATS.

Pleuropulmonary blastoma. A rare childhood malignancy.

Pleuropulmonary blastoma PPB is an extremely rare, intrathoracic neoplasm of early childhood with unfavorable outcome. We present a case of a 4-year-old boy with progressive dyspnea due to tension pneumothorax. After chest tube insertion, the CT scan showed large multilocular cystic lesions containing air and solid areas involving the right lower lobe, and its related pleura. Thoracotomy was carried out, and the cyst was removed with the pleural solid areas. Histopathological examination confirmed the diagnosis of PPB type II. Postoperatively, the patient was scheduled to start chemotherapy in a specialized pediatric oncology center to complete the treatment.