Investigating how often daily weights are recorded in acute heart failure patients

Introduction

Acute heart failure (AHF) is a leading cause of hospital admissions, accounting for nearly 70,000 admissions in the UK in 2019-20. AHF can present as new-onset or decompensated chronic heart failureA. Symptoms arise from a build-up of fluid in the lungs or body causing dyspnoeaand peripheral oedemarespectively. The mainstay treatment of fluid retention is diuretics. Both NICE and local trust (ICHT) guidelines recommend close monitoring of weight whilst on treatment. Daily weights are an objective measure of fluid balance and guide titration of diuretic dose. We noted that within an acute unit in a busy tertiary hospital these weight measurements were not recorded consistently.

Aims

1. Investigate how often daily weights are documented in AHF inpatients

2. Explore whether prescribing daily weights is associated with higher documentation rates

Target criteria & Standard

NICE Clinical guideline [CG187] Acute heart failure: diagnosis and management: 1.3.5 Closely monitor the person's renal function, weight and urine output during diuretic therapy.

ICHT Acute heart failure guideline: 5.6.1 Management of the haemodynamicallystable patient with AHF - 1. All patients should be weighed daily

Method

A retrospective analysis of 55 inpatients referred to the AHF specialist team between 1st November and 31st December 2021 was performed. Patients were required to fit stringent inclusion and exclusion criteria. For each patient, we recorded the total length of stay in days and the number of daily weights documented. As part of the secondary analysis, we hypothesised drug chart would have higher documentation rates (ICHT uses Cerner EPR a type of electronic patient record). Therefore, we also recorded if were compared, between patients prescribed daily weights on the drug chart and those who were not, with an unpaired T-test.

Results

There were 32 patients who met our criteria (M:F 56:43%, age 77.7±2.5). (83% vs 46%, p<0.05), however only 25% of patients had this prescribed.

Discussion

Daily weights may not always be prioritised in busy departments andcan be missed in handovers, particularly when patients are moved to healthcare staff to measure and monitor this parameter, with the added benefit of allowing easy comparison of diuretic dose and effect. Studies have shown that inpatient weight loss in those with decompensated heart failure is associated with lower mortality, reduced length of stay and lower hospital readmissionB. This suggest that regular body weight measurements, which is a measure of success for diuresis, can improve clinical outcomes. Daily measurement also allows for setting a target of weight loss e.g. 0.5kg/day and can identify when diuretic dose resistance starts following prolonged treatmentC

Recommendations for change

This audit highlights there is scope for improving weight recording and has identified a novel method for addressing this. The act of writing in increasing the measurements rates. This simple and cost-effective change is easy to implement in all trusts that use both electronic and paper drug charts. We suggest advising doctors on the medical take, in the acute medical units and acute pharmacists of this simple addition when prescribing diuretics.

Limitations

A potential confounding factor in our data wassome patients refused to have weights measured, leading to an underestimation of readings. We focussed on one aspect of diuretic monitoring and ideally would have also audited how well renal function and urine output are recorded, as per NICE guidelines. Lastly, the generalisability of our data is limited due to the relatively small sample size, single hospital location and restricted selection of patientsreferred to the AHF specialist team. Future audits should aim to expand the cohort of patients and collect data points such as morbidity, mortality and readmissions rates to demonstrate whether increased monitoring of daily weights improves clinical outcomes.

Implementation and Re-audit

These findings form the basis of our quality improvement project, which is currently in progress. In the first PDSA cycle taking place over the month of February, the findings were shared with the cardiology team who, with the AHF nurses, started prescribing referred patients. In the second PDSA cycle we presented our findings to doctors in the acute unit, put a message in the medicine newsletter and placed posters around the hospital. In the nextcycle we plan to survey the nurses on medical wards to identify any barriers. Initial results are promising with daily weights rising from 46% to 70% and 67% of admission days in Feb (n=15) and Mar (n=8) respectively. Finding methods to maintain this long-term will be key.