Evaluation of Cardiac Index and Extravascular Lung Water After Single-Lung Transplantation Using the Transpulmonary Thermodilution Technique by the PiCCO2 Device

Abstract

Objectives: First evaluation of the transpulmonary thermodilution technique by the PiCCO2 device to assess cardiac index and pulmonary edema during the postoperative course after single-lung transplantation.

Design: Prospective observational study.

Settings: Intensive care unit, university hospital (single center).

Participants: Single-lung transplant patients.

Interventions: The authors compared cardiac index measured by PiCCO2 and pulmonary artery catheter and assessed pulmonary edema using extravascular lung water index and pulmonary vascular permeability index measured by PiCCO2.

Measurements and main results: A Bland-Altman method was used to compare cardiac index measured by PiCCO2 and pulmonary artery catheter. Extravascular lung water index and pulmonary vascular permeability index were compared according to the PaO₂/FiO₂ ratio with a threshold value of 150 mmHg. Ten single-lung transplant patients were included. Cardiac index measured by PiCCO2 and pulmonary artery catheter were 3.3 L/min/m² (2.9-3.6) and 2.5 L/min/m² (2.2-3.0). Bias for cardiac index was 0.71 L/min/m² (-0.03; 1.44) and limit of agreements were -0.03 and 1.44 L/min/m². Extravascular lung water index was 12 mL/kg (11-16) and pulmonary vascular permeability index was 2.3 (2.0-3.1), consistent with pulmonary edema. Extravascular lung water index was higher in the group of PaO₂/FiO₂ ratio ≤150 mmHg compared with the group of PaO₂/FiO₂ ratio >150 mmHg (17 v 12 mL/kg, p = 0.04), whereas pulmonary vascular permeability index only tended to be higher (3.1 v 2.1, p = 0.06).

Conclusion: PiCCO2 device systematically overestimated cardiac index compared with pulmonary artery catheter. However, it might be useful to assess pulmonary edema in acute respiratory failure after single-lung transplantation.

Keywords: PiCCO; cardiac output; extravascular lung water index; lung transplantation; pulmonary vascular permeability index; thermodilution.