S GLEESON1, M LAM PO TANG1
1Middlemore Hospital, Auckland, New Zealand
Aim: We compared fluid assessment by clinicians of varying experience with assessment using a Fresenius Body Composition Monitor (BCM) in haemodialysis patients. We also aimed to identify clinical factors that lead to inter-clinician variability and inaccuracy.
Background: Both overhydration and underhydration are associated with significant morbidity in haemodialysis patients. Optimising fluid balance is a cornerstone of dialysis therapy.
Clinical fluid assessment is difficult and likely done poorly, hampered by non-specific symptoms and unreliable signs. The BCM has been validated to accurately assess fluid balance.
Methods: Clinical fluid assessments were performed on 20 stable haemodialysis patients by at least 3 clinicians (house officer (HO), registrar, renal consultant) and by BCM. Primary outcome was difference between clinical and BCM assessment. Variables including clinician experience, body mass index (BMI), and cardiac dysfunction were recorded. Statistical analysis was performed on Stata 12®. Parametric analyses were performed using ANOVA with Bonferroni adjustment. Non-parametric analyses were performed using logistic regression and Fisher’s exact test.
Results: Mean patient age was 50.3 ± 13.3 years, 20% were female, 60% were Pacific Islander, 25% Maori.79 clinical fluid assessments were carried out (26 HOs, 26 registrars, 27 consultants). The mean difference from the BCM was -0.25 ± 2.9L for HO, -1.38 ± 2.7L for registrars, 0.34 ± 2L for consultants (p = 0.78). Body mass index > 35 kg/m2 (p = 0.017) and moderate right ventricular dysfunction (p =0.003) were associated with greater inaccuracy.
Discussion: Despite the small sample size we demonstrated inaccuracies in clinical fluid assessment irrespective of clinician experience and identified some clinical factors leading to inaccurate clinical fluid assessment. Further studies with greater numbers are needed to confirm this trend.