A comparative study of glucose concentration determined from venous plasma sample and capillary blood sample

Context: Self-monitoring of glucose levels with a hand held glucometer is very popular among the diabetic patients and doctors as it is less traumatic and gives instant results. Capillary blood samples are commonly used for self-monitoring in comparison to venous plasma sample which are used in the diagnostic laboratories. Aims: This study was done to compare the glucose levels of a capillary blood sample determined by a glucometer with the glucose level determined by Glucose Oxidase Peroxidase (GOD-POD) method using a venous plasma sample. Setting and Design: This experimental study was carried out at Rohilkhand Medical College and Hospital. Methods and Material: Two hundred patients were randomly selected for the study. Their venous blood samples were collected in a fluoride containing blood collection tube. The plasma obtained was subjected to GOD-POD test. Simultaneously their capillary blood glucose was also determined by a glucometer. Statistical analysis used: The data collected was analyzed using SPSS 17.0 version. Data was expressed as mean ± SD. Significance of mean was analyzed using paired t test. P value < 0.05 was considered significant. Result: Glucose levels determined by a glucometer and GOD-POD method showed very good correlation (r=0.958; p<0.001). However, at very high and low glucose levels, the glucometer significantly under estimated (p=0.014) and over-estimated (p<0.001) the glucose levels respectively. Conclusion: Although glucometers are effective for routine monitoring of glucose levels, they should be used cautiously in emergency conditions.