Comparison between clinical judgment and integrated lung and inferior vena cava ultrasonography for dry weight estimation in hemodialysis patients.

INTRODUCTION: Correct dry weight estimation is very crucial for hemodialysis (HD) patients to maintain euvolemia. Most dialysis centers practice clinical judgment for dry weight estimation, which is subjective and can differ significantly from the actual weight. We designed this study to redefine the clinically estimated dry weight of patients on HD using integrated lung-inferior vena cava (IVC) ultrasonography (USG) and compare the symptoms arising due to volume overload and/or volume depletion before and after modifying the dry weight.

METHODS: Breathlessness and orthostatic giddiness were scored and documented for 2 weeks while patients were on HD based on clinically estimated dry weight and again for 2 weeks after redefining dry weight using lung-IVC USG. New dry weight was defined as the weight of the patient at which the number of B-lines was <4 on eight site lung USG and IVC collapsibility index was between 50% and 75%.

FINDINGS: After redefining the dry weight, 34 patients (group I) had change in dry weight and 40 (group II) had no change. There was 0.21 ± 1.80 reduction in the score for orthostatic giddiness in group I and 0.03 ± 0.16 in group II (P = 0.147). The score for breathlessness during the 24 hours following dialysis reduced by 0.21 ± 0.41 in group I, but did not change in group II (P = 0.003). Score for breathlessness in the predialysis day reduced by 0.56 ± 0.56 in group I and by 0.05 ± 0.22 in group II (P < 0.001).

DISCUSSION: Symptoms related to volume overload and depletion were less when HD prescription was based on lung-IVC USG defined dry weight.