#2875 CONGESTION PHENOTYPES AND DECONGESTION PATTERNS ASSESSED BY POCUS IN HAEMODIALYSIS PATIENTS: A PILOT STUDY
Authors: Romero-González Gregorio A , Lanau Maria , Soler Jordi , Torres Fredzzia Amada Graterol , Rodriguez-Chitiva Nestor , Castaño Itziar , Riera Josep , Urrutia Marina , Manrique Joaquín , Bover Jordi 
Published: June 2023

Abstract

Background and Aims
Despite the evolution of hemodialysis (HD) in recent years, cardiovascular diseases continue to be the main cause of death in this group of patients. Congestion is one of the factors associated with the highest morbidity and mortality. Unfortunately, there is no gold standard for the proper assessment of dry weight; in fact, physical examination, and even newer techniques such as bioimpedance have poor sensitivity, are difficult to interpret in some cases and fail to discriminate between tissular and vascular congestion. Recently, the use of Point-of-care Ultrasonography (PoCUS) has emerged as the fifth pillar of the conventional physical examination that allows dynamic assessment of congestion and enables congestion to be phenotyped. The aims of the present study were: 1. to phenotype congestion in HD patients and 2. to establish patterns of decongestion according to changes in phenotypes over the course of a HD session.

Method
Descriptive study carried out in HD units of two tertiary hospitals. Patients with more than three months on HD were included. Excluding patients with short life expectancy or who had an acute complication. In addition to the congestive composite score (CCS), a PoCUS evaluation was performed at the beginning and the end of the HD session on long dialysis interval. Tissular congestion was assessed by lung ultrasound and vascular congestion was assessed by evaluation of the inferior vena cava diameter and portal vein pulsation by pulsed Doppler. Four phenotypes of congestion were established: phenotype A: no congestion, phenotype B: predominance of tissue congestion, phenotype C: predominance of vascular congestion and phenotype D: mixed congestion. In addition, 4 patterns of decongestion were established: pattern 1: absence of congestion at the beginning and end of the HD session, pattern 2: change of phenotype from B, C or D to A, pattern 3: change in congestion phenotype and pattern 4: persistence in the same congestion phenotype as at the beginning.

Results
20 patients were included, mean age: 70.5±11.3 years, 14 (70%) were male, CCS: 3 (1.5 – 7.5), interdialysis weight gain: 2.93±0.95 kg and mean UF: 2,570±868mL. 75% of patients reached the prescribed dry weight. At the beginning of the session the distribution of phenotypes was: phenotype A: 35%, phenotype B: 25%, phenotype C: 25% and phenotype D: 15%. At the end of the HD session: phenotype A: 55%, phenotype B: 30%, phenotype C: 10% and phenotype D: 5%. At the end of the HD session 45% of the patients persisted with ultrasound congestion. As for the patterns of decongestion: pattern 1: 35% of patients, pattern 2: 10%, pattern 3: 10% and pattern 4: 35%. 45% of patients persisted with some phenotype of congestion at the end of the session. An inverse correlation was found between age and phenotype at baseline (Rho: -0.506; p = 0.023). No correlation was found between dry weight and UF with decongestion patterns.

Conclusion
These results show the persistence of echographic congestion at the end of the HD session in a significant number of patients, suggesting that subclinical congestion is more frequent than clinically observed. Further studies are warranted to confirm these results.