Dynamic changes and prognosis of pulmonary congestion by lung ultrasound in hemodialysis patients: a systematic review and meta-analysis.

Aims: Lung ultrasound (LUS) has been rapidly developed to evaluate pulmonary extravascular fluid. A systematic review was conducted to study the dynamic changes of LUS findings of pulmonary congestion before and after hemodialysis and examine the application of LUS for the prognosis of hemodialysis patients.

Material and methods: This study searched online databases for articles on hemodialysis patients that used LUS to evaluate dynamic changes during hemodialysis or prognosis. Articles published in English or Chinese until September 2021 with ≥30 patients were included in this study.

Results: Of the 1329 articles, 14 met the inclusion criteria: 9 reported dynamic changes during dialysis in LUS (438 patients), and 5 reported the prognosis of hemodialysis patients in LUS (1274 patients). As indicated by a further meta-analysis, eight studies found that the combined standardized effect size was -0.74. The all-cause mortality rate of the dialysis patient group with high B-line scores was three times that of the dialysis patient group with low B-line scores. In dialysis patients, no difference was found between the LUS guided treatment and the conventional care in reducing the all-cause mortality (HR=0.92 95%CI: 0.67-1.27) and cardiovascular events (HR=0.98 95%CI: 0.72 -1.34).

Conclusions: LUS can be used to effectively evaluate the volume status of hemodialysis patients in real time. The level of B-line before dialysis is significantly correlated with the poor prognosis. However, compared with the routine nursing group, the treatment of hemodialysis patients with LUS-guided volume management cannot effectively reduce mortality and cardiovascular events.