Relationship between lung ultrasound and electrical impedance tomography as regional assessment tools during PEEP titration in acute respiratory distress syndrome caused by multi-lobar pneumonia: a pilot study.

Acute respiratory distress syndrome (ARDS) caused by multilobar pneumonia (MLP) is markedly different from typical ARDS in pathology, imaging characteristics, and lung mechanics. Regional lung assessment is required. We aimed to analyze the relationship between two regional assessment tools, lung ultrasound (LUS) and electrical impedance tomography (EIT) during positive end-expiratory pressure (PEEP) titration, and determine an appropriate PEEP level. We conducted a prospective study of patients with ARDS caused by MLP with PaO2/FiO2 < 150 mmHg. All subjects were equipped with two EIT belts connected with a single EIT machine to measure upper and lower hemithorax impedance change alternatingly at each PEEP level. LUS score was simultaneously determined in chest wall regions corresponding to the EIT regions during PEEP titration. We acquired EIT and LUS data in eight regions of interest at seven PEEP levels in 12 subjects. Therefore, 672 pairs of data were obtained for analysis. There were significant relationships between LUS score and tidal impedance variation and pixel compliance (Cpix). The Spearman's rho between LUS score vs. tidal impedance variation and LUS score vs. the Cpix were - 0.142, P < 0.001, and - 0.195, P < 0.001, respectively. The relationship between the LUS score and Cpix remained the same at every PEEP level but did not reach statistical significance. The individual's mean expected PEEP by LUS was similar to the EIT [10.33(± 1.67) vs. 10.33(± 1.44) cm H2O, P = 0.15]. Regarding the MLP, the LUS scores were associated with EIT parameters, and LUS scores might proof helpful for finding individual PEEP settings in MLP.

Easy prognostic assessment of concomitant organ failure in critically ill patients undergoing mechanical ventilation.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a life-threatening disease. We evaluated the prognostic utility of Model for End-stage Liver Disease excluding INR (MELD-XI) score for predicting mortality in a cohort of critically ill patients on mechanical ventilation. METHODS: In total, 11,091 mechanically ventilated patients were included in our post-hoc retrospective analysis, a subgroup of the VENTILA study (NCT02731898). Evaluation of associations with mortality was done by logistic and Cox regression analysis, an optimal cut-off was calculated using the Youden Index. We divided the cohort in two sub-groups based on their MELD-XI score at the optimal cut-off (12 score points). RESULTS: Peak-, plateau- and positive end-expiratory pressure were higher in patients with MELD-XI>12. Patients with MELD-XI>12 had higher driving pressures (14 ±â€¯6 cmH2O versus 13 ±â€¯6; p < 0.001). MELD-XI was associated with 28-day mortality after correction for relevant cofounders including SAPS II and ventilation pressures (HR 1.04 95%CI 1.03-1.05; p < 0.001. Patients with MELD-XI>12 evidenced both increased hospital (46% versus 27%; p < 0.001) and 28-day mortality (39% versus 22%). CONCLUSIONS: MELD-XI is independently associated with mortality and constitutes a useful and easily applicable tool for risk stratification in critically ill patients receiving mechanical ventilation. TRIAL REGISTRATION: NCT02731898, registered 4 April 2016.

Transthoracic ultrasound assessment of B-lines for identifying the increment of extravascular lung water in shock patients requiring fluid resuscitation.

INTRODUCTION: Several studies have shown that the number of B-lines was related to the amount of extravascular lung water (EVLW). In our study, we aimed to demonstrate the magnitude of the incremental B-lines in shock patients with positive net fluid balance and the association with gas exchange impairment. MATERIALS AND METHODS: We performed trans-thoracic ultrasound at admission (T0) and at follow-up period (TFL) to demonstrate the change of B lines (ΔB-lines) after fluid therapy. We compared the total B-line score (TBS) at T0 and TFL and calculated the Pearson's correlation coefficient between the ΔB-lines and PaO2/FiO2 ratio. RESULTS: A total of 20 patients were analyzed. All patients had septic shock. Net fluid balance was + 2228.05 ± 1982.15 ml. The TBS at T0 and TFL were 36.6 ± 23.73 and 63.80 ± 29.25 (P < 0.01). The ΔB-lines along anterior axillary line (AAL) correlated to the ΔTBS (r = 0.90, P < 0.01). The ΔB-lines along AAL had inverse correlation to PaO2/FiO2 ratio (r = -0.704, P < 0.05). The increase of B-lines ≥ 10 was related to the decrease of PaO2/FiO2 ratio. The inter-observer reliability between two ultrasound readers was high (r = 0.92, P < 0.01). DISCUSSION: The number of B-lines increased in shock patients with positive net fluid balance and correlated to impaired oxygenation. These data supported the benefit of ultrasound for assessing the EVLW.