Authors (including presenting author) :
Leung LBS (1,4), Cheung SM (1,4), Tse CK (2,4), Lo WS (2,4), Leung CY (1,4), Ng MYA (5), Ho HS (1,4), Lam KMA (3,4), Lau SLT (1,4), Ng TTC (2,4), Yuen YK (2,4), Tsang WK (2,4), Mak MY (2,4)
Affiliation :
(1) Department of Medicine, (2) Department of Community Nursing Services, (3) Department of Specialist Out-patient, (4) Pamela Youde Nethersole Eastern Hospital, (5) Violet Peel General Out-Patient Clinic, Hong Kong East Cluster
Introduction :
Self-monitoring of blood glucose (SMBG) is considered as most essential part of diabetes management. Accurate SMBG records are crucial for timely and appropriate decisions on diet, exercise, and medication for optimal glycaemic control. However, there are some controversies on capillary blood sampling practices and no standardized guideline. This study would explore the accuracy of SMBG results from capillary blood sampling.
Objectives :
To evaluate the accuracy of 1st and 2nd drop of blood for fasting capillary glucose in patients with diabetes requiring self-monitoring of blood glucose
Methodology :
The study was implemented in HKEC from 1 - 30 June 2018. Out-patients who aged ≥18 with type 1 and 2 diabetes requiring fasting blood glucose sampling, no vasoconstriction or limbs edema, and gave verbal consent were recruited. 3 community nurses were trained for standardized blood sampling. The 1st and 2nd fasting capillary glucose (FCG) samples were measured separately by the same blood glucose meter. Obtained FCG sample was compared with fasting plasma glucose (FPG) in the same visit. Means difference was compared using unpaired t-test and Spearman’s Rho test using SPSS.
Result & Outcome :
24 patients were randomly assigned to the intervention group whilst another 24 to the control. The mean difference for 1st FCG vs FPG was 0.66 (SD=3.38) mmol/L, whereas 0.64 (SD=4.58) mmol/L for 2nd FCG vs FPG result. There was no statistically significant difference (p=0.089) between the 1st and 2nd drop of capillary blood. However, a statistically significant association existed between 1st and 2nd FCG samples (R=0.639, Spearman’s Rhos test). Positive correlation between 2 FCG samplings comparing with FPG measurement that indicated it was acceptable accuracy. Both 1st and 2nd drop of capillary blood are reliable in performing SMBG. Using the 1st drop of capillary blood is recommended clinically to save time, minimize procedural pain and conserve medical resources. Hand washing and no visible dirt before procedure is essential to gain accurate venous glucose result. Besides, capillary blood sampling should be adequate, in circular shape & properly apply to the test strip of blood glucose meter.