Final answer:
The butterfly needle should be inserted at an angle of 15-30 degrees into the hand's veins, such as the palmar venous arches, radial vein, ulnar veins, and median antebrachial vein, for successful venipuncture.
Step-by-step explanation:
The angle of entry in a hand vein with a butterfly needle is critical for successful venipuncture. When using a butterfly needle for venipuncture on veins in the hand, it's important to understand the anatomy involved to ensure a correct approach. The hand's venous system includes the digital veins which drain the digits and feed into the palmar venous arches. From there, blood is carried to larger veins such as the radial vein, ulnar veins, and the median antebrachial vein.
The median antebrachial vein is of particular interest since it runs medially, parallel to the ulnar vein, and is intertwined with the palmar venous arches. Ultimately, it joins the basilic vein which then feeds into the systemic circulation via superficial and deep pathways.
When performing a venipuncture on the hand or the more commonly used median cubital vein in the antecubital area, it's crucial to insert the butterfly needle at an appropriate angle, typically 15-30 degrees to ensure proper entry and to minimize discomfort and injury to the patient. Proper technique in venipuncture is vital for obtaining an adequate sample and for the safety and comfort of the patient.