The use of whole blood capillary samples to measure 15 analytes for a home-collect biochemistry service during the SARS-CoV-2 pandemic: A proposed model from North West London Pathology

Abstract

Background The COVID-19 pandemic has drastically changed the delivery of secondary care services. Self-collection of capillary blood at home can facilitate the monitoring of patients with chronic disease to support virtual clinics while mitigating the risk of SARS-CoV-2 infection and transmission. Objective To investigate the comparability of whole blood capillary and plasma venous samples for 15 routinely used biochemical analytes and to develop and pilot a use-friendly home-collection kit to support virtual outpatient clinical services. Methods To investigate the comparability of whole blood capillary and plasma venous samples for 15 routinely requested biochemical analytes, simultaneous samples of venous and capillary blood were collected in EDTA and lithium-heparin plasma separation tubes that were of 4-6mL and 400-600µL draw volume, respectively. Venous samples were analysed within 4 hours of collection while capillary samples were kept at ambient temperature for 3 days until centrifugation and analysis. Analyte results that were comparable between the matrices were then piloted in a feasibility study in three outpatient clinical services. Results HbA1c, lipid profile and liver function tests were considered comparable and piloted in the patient feasibility study. The home-collect kit demonstrated good patient usability. Conclusion Home collection of capillary blood could be a clinically-useful tool to deliver virtual care to patients with chronic disease.

Remote capillary blood collection for HbA1c measurement during the COVID‐19 pandemic: A laboratory and patient perspective

“…Good concordance has been reported in the literature for HbA 1c measured in capillary and venous blood samples using both dried blood spot devices and collection tubes 9,16–19 . Two previous studies reported that 69.2% and 70% of participants, respectively, would use a remote HbA 1c service if available or recommend this service 1,16 . Our study gave similar results with over three quarters of respondents (75.4% [43/57]) reporting that they would use the remote HbA 1c service routinely if available.…”

“…9,[16][17][18][19] Two previous studies reported that 69.2% and 70% of participants, respectively, would use a remote HbA 1c service if available or recommend this service. 1,16 Our study gave similar results with over three quarters of respondents (75.4% [43/57]) reporting that they would use the remote HbA 1c service routinely if available.…”

“…Diabetes is a chronic disease in which individuals require ongoing support from diabetes services. The severity of the current COVID‐19 pandemic has disrupted this provision of support; to minimize the spread of SARS‐CoV‐2 infection and to support social distancing measures, many phlebotomy appointments have been stopped and face‐to‐face consultations replaced by remote virtual or telephone appointments 1 . Consequently, people with diabetes have had reduced access to routine appointments and regular monitoring of glycated haemoglobin (HbA 1c ).…”

“…The severity of the current COVID‐19 pandemic has disrupted this provision of support; to minimize the spread of SARS‐CoV‐2 infection and to support social distancing measures, many phlebotomy appointments have been stopped and face‐to‐face consultations replaced by remote virtual or telephone appointments. 1 Consequently, people with diabetes have had reduced access to routine appointments and regular monitoring of glycated haemoglobin (HbA 1c ). HbA 1c is the product of in vivo non‐enzymatic glycation of haemoglobin, a process which is proportional to the plasma glucose concentration and occurs throughout the lifespan of a red blood cell (RBC).…”

Challenges and opportunities to diabetes and endocrinology training during and beyond the COVID‐19 pandemic

“…As people with diabetes are considered clinically vulnerable, exposure to COVID is best minimised where safe and possible. The pandemic saw further innovations to facilitate virtual diabetes outpatient consultations, such as home collection of capillary blood samples for HbA 1c and creatinine and urine for microalbumin measurement which are then posted by the patient to the laboratory 15 . These advances should serve as a stimulus for further training in the use of newer remote diabetes technologies; trainees could then support their incorporation into diabetes care in the community.…”