Blood Draw Techniques and Considerations

Blood Draw Considerations

• Mastectomy and Lymph Nodes

  • Mastectomy often involves removal of lymph nodes.

  • Concern arises over cancer spreading to lymph nodes.

  • Complications can lead to swelling in the arm due to fluid circulation issues.

• Drawing Blood from Tattoos

  • Tattoos should generally be avoided for blood draws due to potential complications.

  • While some practices allow drawing through tattoos, the standard caution is to select a different site.

  • Preferred alternatives might include the foot or other unaffected areas.

• Hematoma (Bruises)

  • Hematomas are essentially bruises; do not draw blood through bruised areas.

  • Pain and the presence of old blood could compromise sample quality.

• Edema

  • Edema refers to excess fluid accumulation causing swelling in tissues.

  • Pitting Edema: Characterized by a divot remaining after pressure is applied to swollen areas.

  • Common in pregnant women and individuals with certain health conditions.

  • Important to assess for pitting when choosing blood draw sites.

• Scars

  • Avoid drawing blood through scar tissue, as it can be hard and painful.

  • Scar tissue extends beneath the skin, which can affect both the draw process and patient comfort.

• Sclerosis

  • Sclerotic veins are hardened, and blood should not be drawn from them.

  • Hard veins are likely due to aging or overuse (often seen in individuals with a history of IV drug use).

Tourniquet Use

• Purpose: A tourniquet is used to engorge veins temporarily for easier blood draw access.

  • Apply 3-4 inches above the venipuncture site, ensuring it is snug but not overly tight to cut off circulation.

• Application Tips:

  • Do not tie a knot; instead, tuck it to allow for quick removal.

  • Monitor tourniquet time; it must be removed within one minute to avoid effects like hemoconcentration (buildup of red blood cells leading to skewed sample results).

  • If necessary, can use a blood pressure cuff as an alternative for larger arms.

Key Concepts to Remember

• Hemoconcentration: Excess accumulation of red blood cells due to prolonged tourniquet application.

• Aim for quick and effective blood draws while keeping patient comfort in mind.

• Always assess the condition of the vein before proceeding with a blood draw to ensure patient safety and sample integrity.

• Practice Drills: Engage in practical sessions, adjusting techniques based on individual comfort and efficacy. Consider personal preferences for playground techniques (e.g., whether to place the tourniquet over or under the arm).