Computer-Aided Quantitative Ultrasonography for Detection of Pulmonary Edema in Mechanically Ventilated Cardiac Surgery Patients.

Abstract

BACKGROUND:

Lung ultrasonography (LUS) has been used for noninvasive detection of pulmonary edema. Semiquantitative LUS visual scores (visual LUS [V-LUS]) based on B lines are moderately correlated with pulmonary capillary wedge pressure (PCWP) and extravascular lung water (EVLW). A new computer-aided quantitative LUS (Q-LUS) analysis has been recently proposed. This study investigated whether Q-LUS better correlates with PCWP and EVLW than V-LUS and to what extent positive end-expiratory pressure (PEEP) affects the assessment of pulmonary edema by Q-LUS or V-LUS.

METHODS:

Forty-eight mechanically ventilated patients with PEEP of 5 or 10 cm H2O and monitored by PCWP (n = 28) or EVLW (n = 20) were studied.

RESULTS:

PCWP was significantly and strongly correlated with Q-LUS gray (Gy) unit value (r(2) = 0.70) but weakly correlated with V-LUS B-line score (r(2) = 0.20). EVLW was significantly and more strongly correlated with Q-LUS Gy unit mean value (r(2) = 0.68) than with V-LUS B-line score (r(2) = 0.34). Q-LUS showed a better diagnostic accuracy than V-LUS for the detection of PCWP >18 mm Hg or EVLW ≥ 10 mL/kg. With 5-cm H2O PEEP, the correlations with PCWP or EVLW were stronger for Q-LUS than V-LUS. With 10-cm H2O PEEP, the correlations with PCWP or EVLW were still significant for Q-LUS but insignificant for V-LUS. Interobserver reproducibility was better for Q-LUS than V-LUS.

CONCLUSIONS:

Both V-LUS and Q-LUS are acceptable indicators of pulmonary edema in mechanically ventilated patients. However, at high PEEP only Q-LUS provides data that are significantly correlated with PCWP and EVLW. Computer-aided Q-LUS has the advantages of being not only independent of operator perception but also of PEEP.

• Authors: Francesco Corradi, Claudia Brusasco, Antonella Vezzani, Gregorio Santori, Tullio Manca, Lorenzo Ball, Francesco Nicolini, Tiziano Gherli, Vito Brusasco
• Journal: Chest (Chest) Vol. 150 Issue 3 Pg. 640-51 (Sep 2016) ISSN: 1931-3543 [Electronic] United States
• PMID: 27130285 (Publication Type: Journal Article, Observational Study)
• Copyright: Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Topics

• Aged
• Cardiac Surgical Procedures
• Extravascular Lung Water (diagnostic imaging)
• Female
• Humans
• Image Processing, Computer-Assisted
• Lung (diagnostic imaging)
• Male
• Middle Aged
• Positive-Pressure Respiration
• Postoperative Complications (diagnostic imaging)
• Prospective Studies
• Pulmonary Edema (diagnostic imaging)
• Pulmonary Wedge Pressure
• Reproducibility of Results
• Respiration, Artificial
• Ultrasonography