Utilisation of Remote Capillary Blood Testing in an Outpatient Clinic Setting to improve shared decision making and patient and clinician experience: a validation and pilot study

Background In a tertiary respiratory centre, large cohorts of patients are managed in an outpatient setting and require blood tests to monitor disease activity and organ toxicity. This requires either visits to tertiary centres for phlebotomy and physician review or utilisation of primary care services. Objectives This study aims to validate remote capillary blood testing in an outpatient setting and analyse impact on clinical pathways. Methods A single-centre prospective cross-sectional validation and parallel observational study was performed. Remote finger prick capillary blood testing was validated compared to local standard venesection using comparative statistical analysis: paired t-test, correlation and Bland-Altman. Capillary was considered interchangeable with venous samples if all 3 criteria were met: non-significant paired t-test (i.e. p>0.05), Pearson's correlation coefficient (r) >0.8 and 95% of tests within 10% difference through Bland-Altman (Limits of agreement). In parallel, current clinical pathways including phlebotomy practice was analysed over 4 weeks to review test predictability. A subsequent pilot cohort study analysed potential impact of remote capillary blood sampling on shared decision making and outpatient clinical pathways. Results 117 paired capillary and venous blood samples were prospectively analysed. Interchangeability with venous blood was seen with HbA1c (%), total protein and CRP. Further tests, although not interchangeable, are likely useful to enable longitudinal remote monitoring (e.g. liver function, total IgE, and vitamin D). 65% of outpatient clinic blood tests were predictable with 16% of patients requiring further contact due to actions required. Pilot implementation of remote capillary sampling showed patient and clinician-reported improvement in shared decision-making given contemporaneous blood test results. Conclusions Remote capillary blood sampling can be used accurately for specific tests to monitor chronic disease, and when incorporated into an outpatient clinical pathway can improve shared decision making and patient experience. Further research is required to determine health-economic impact and applicability within telemedicine-based outpatient care.