The Physiological Challenges of Geriatric Phlebotomy
With age, several physiological changes occur that directly impact the phlebotomy process. The skin becomes thinner and loses elasticity, while veins become more fragile, less elastic, and tend to roll more easily. Subcutaneous tissue diminishes, causing veins to be closer to the surface. Many elderly patients also take anticoagulant medications, increasing their risk of bruising and hematoma formation. These factors necessitate a modified approach to venipuncture, with a strong focus on avoiding practices that would be routine for younger patients.
Avoiding Incorrect Equipment and Site Selection
Selecting the right tools and location is the first step toward a successful draw. Using equipment and sites suitable for a typical adult can cause significant harm to an older patient.
Equipment Choices to Steer Clear Of
- Large-Gauge Needles: Avoid using standard large-bore needles (e.g., 20 or 21 gauge) that are appropriate for most adults. The greater vacuum pressure and larger size can cause fragile geriatric veins to collapse or rupture. A smaller, gentler option, such as a 23 or 25-gauge butterfly needle, is preferable as it minimizes trauma and is easier to control.
- Overly Aggressive Vacuum Tubes: In conjunction with smaller-gauge needles, avoid using large evacuated tubes that have a strong vacuum. The high suction can collapse delicate veins. Use smaller pediatric-sized tubes instead, as their lower vacuum pressure is more appropriate for fragile vessels.
- Standard Adhesive Bandages: Thin, delicate skin is highly susceptible to tearing or blistering when a standard adhesive bandage is removed. Steer clear of these, and instead, opt for paper tape and gauze or a non-adhesive dressing to secure the site.
- Tightly Tied Tourniquets: A tightly wrapped tourniquet can cause petechiae (small red spots from bleeding under the skin) and hematomas in elderly patients with fragile capillaries. Use a Velcro or clip tourniquet and apply it loosely, or place it over the patient's clothing. If the patient's veins are prominent enough, a tourniquet may not be needed at all.
Venipuncture Sites to Shun
- Bruised or Scarred Areas: Always avoid sites with existing bruising, scarring, or abrasions. These areas can be more painful and can yield inaccurate test results due to tissue damage.
- Areas with Edema: Drawing from an edematous (swollen) extremity should be avoided as the fluid accumulation can dilute the blood specimen, skewing test results.
- Arms with Mastectomies: Never perform venipuncture on the arm on the same side as a mastectomy. Lymph nodes may have been removed, increasing the risk of infection and lymphedema.
- The Underside of the Wrist: The underside of the wrist is a sensitive area with superficial nerves and arteries. Needlestick injuries here can be especially painful and cause nerve damage. Stick to the back of the hand or the antecubital fossa.
Impermissible Phlebotomy Techniques
Certain habits and techniques common in phlebotomy must be adjusted or abandoned entirely when dealing with geriatric patients.
Techniques to Avoid at all Costs
- Excessive Probing: A missed vein should not be met with repeated, forceful probing. This causes significant pain, damages tissue, and greatly increases the risk of hematoma. Instead, withdraw the needle and try a different site.
- Tapping or Slapping the Skin: Firmly tapping or slapping the skin to make veins more prominent is an outdated and aggressive technique. For older patients, this can cause bruising and is disrespectful. Instead, use a warm compress or allow the arm to hang down to help dilate the veins.
- Ignoring Patient Input: Many elderly patients have had numerous blood draws and may know which arm or vein is best. Failing to listen to their experience can lead to unnecessary difficulty and discomfort. Always consult the patient or their caregiver if possible.
- Leaving the Tourniquet on Too Long: Leaving a tourniquet on for more than one minute can cause hemoconcentration, where plasma is filtered out, and the sample becomes concentrated with cells. This can lead to erroneous lab results. Release and reapply the tourniquet if a suitable vein isn't found quickly.
Errors in Post-Procedure Care
Proper care after the needle is removed is just as important as the draw itself.
Post-Procedure Mistakes
- Insufficient Pressure: Due to potentially longer clotting times (especially for patients on blood thinners), applying pressure for a short period is not enough. Hold pressure for a full 3-5 minutes, or until bleeding has stopped, to prevent a hematoma.
- Asking the Patient to Bend Their Arm: Instructing the patient to bend their elbow after the draw can cause blood to leak from the vein and form a hematoma. The arm should be kept straight and elevated while applying pressure.
Comparison of Practices
| Practice | What to Avoid | What to Do Instead |
|---|---|---|
| Needle Size | Large-gauge needles (20, 21 gauge) | Small-gauge butterfly needles (23, 25 gauge) |
| Tourniquet Use | Tightly tied rubber tourniquets for prolonged periods | Loosely applied clip/Velcro tourniquets over clothing for less than one minute |
| Site Location | Bruised, scarred, edematous areas; underside of wrist | Back of the hand, or undamaged median cubital vein |
| Technique | Forceful tapping, excessive probing, fast insertions | Gentle palpation, warm compress, slow and steady insertion angle (10-20°) |
| Aftercare | Asking patient to bend arm; standard adhesive bandage | Applying sustained, gentle pressure; using paper tape and gauze |
It is essential for any healthcare provider to be well-versed in these modified techniques to ensure the best possible experience and outcome for the elderly patient. For more information on general phlebotomy best practices, refer to the WHO guidelines on drawing blood.
Conclusion
Performing phlebotomy on elderly patients demands a high level of patience, gentleness, and adapted technique. By avoiding common errors such as using large-gauge needles, applying tight tourniquets, or failing to anchor delicate veins, professionals can prevent painful complications like bruising, vein collapse, and hematomas. Recognizing the physiological vulnerabilities of aging is the first step toward delivering compassionate and competent care during blood collection.
