Point-of-Care Blood Glucose Testing at Bedside via Finger Stick
Yes, point-of-care (POC) blood glucose testing can be performed at bedside via finger stick, and this is the most common method used in hospitals for glucose monitoring in non-critically ill patients. 1
Standard Practice in Hospital Settings
The vast majority of hospital glucose monitoring is performed using standard glucose monitors and capillary blood taken from fingersticks, similar to the process used by outpatients for home glucose monitoring. 1 This bedside testing approach:
- Provides rapid results at the "point of care" where therapeutic decisions are made 1
- Enhances patient comfort by replacing venipunctures with capillary blood glucose tests 1
- Allows adequately trained personnel to perform the testing 1
- Functions as an additional "vital sign" for hospitalized patients with diabetes 1
Critical Implementation Requirements
Bedside blood glucose monitoring via finger stick requires specific infrastructure 1:
- Clear administrative responsibility for the procedure 1
- A comprehensive procedure manual 1
- A training program for personnel performing the testing 1
- Well-defined quality control procedures 1
- Regularly scheduled equipment maintenance 1
- Mandatory safety standards prohibiting sharing of lancets, testing materials, and needles 1
Important Limitations and Caveats
Accuracy Concerns
POC meters are not as accurate or as precise as laboratory glucose analyzers. 1 Capillary blood glucose readings are subject to artifact due to 1:
- Poor perfusion
- Edema
- Anemia/erythrocytosis
- Several medications commonly used in the hospital
When to Avoid Finger Stick Testing
In critically ill patients, arterial or venous whole blood sampling should be used instead of finger-stick capillary testing for patients in shock, on vasopressor therapy, or with severe peripheral edema, and for any patient on a prolonged insulin infusion. 1
Research demonstrates significant problems with finger stick accuracy in these populations:
- Finger-stick capillary glucose levels may provide significantly different results compared with arterial or venous specimens when patients have low perfusion with hypotension, edema, vasopressor infusion, or mottled skin 1
- Clinical agreement with central laboratory was only 26.3% with capillary blood analysis during hypoglycemia, compared to 55.6-64.9% for arterial blood analysis 2
- In shock patients, fingerstick blood samples should not be used for bedside glucose analysis due to inadequate tissue perfusion 3
- Point-of-care glucose values differed from laboratory values by more than 20 mg/dL in 15-21% of critically ill patients 4, 5
Testing Frequency
For hospitalized patients using finger stick POC testing 1:
- Patients who are eating: glucose monitoring should be performed before meals 1
- Patients not eating: glucose monitoring is advised every 4-6 hours 1
- Patients on continuous intravenous insulin: more frequent testing ranging from every 30 minutes to every 2 hours is required 1
Regulatory Standards
The U.S. Food and Drug Administration has established specific standards for capillary (fingerstick) blood glucose meters used in the ambulatory setting, as well as standards to be applied for POC measures in the hospital. 1