A male client weighing 175 pounds is to receive an intramuscular injection into his deltoid of two milliliters (2 mL) of a viscous fluid.
Which needle size should a nurse use?
A.
1/2 inch, 25 gauge.
B.
1 inch, 23 gauge.
C.
1-1/2 inches, 21 gauge.
D.
2 inches, 16 gauge.
The correct answer and Explanation is :
For administering an intramuscular (IM) injection of 2 mL of viscous fluid into the deltoid muscle, the nurse should use a needle size that ensures proper medication delivery while minimizing patient discomfort. The appropriate choice among the given options is:
B. 1 inch, 23 gauge.
Explanation:
Needle Gauge and Length:
- Gauge refers to the thickness of the needle. A lower gauge number indicates a thicker needle. For viscous fluids, a larger gauge needle (thicker) is needed to ensure the fluid can pass through without excessive resistance. However, it also needs to be balanced with the need for comfort and effective delivery.
- Length refers to how long the needle is. The length needed for an IM injection depends on the muscle’s depth. The deltoid muscle, located in the upper arm, is relatively superficial compared to other muscles like the gluteus maximus or vastus lateralis.
Option Analysis:
- A. 1/2 inch, 25 gauge: This needle is too short for the deltoid muscle, as it may not reach deep enough for effective IM delivery. Additionally, a 25 gauge needle is typically too thin for viscous fluids.
- B. 1 inch, 23 gauge: This needle size is appropriate for injecting 2 mL of a viscous fluid into the deltoid muscle. The 1-inch length is sufficient to penetrate the deltoid muscle without going too deep, while the 23 gauge is large enough to accommodate the viscous fluid.
- C. 1-1/2 inches, 21 gauge: While this needle is long enough for deeper muscles and can handle viscous fluids, it may be too long for the deltoid muscle. The 21 gauge needle is thicker than necessary for a 2 mL viscous fluid in this context, which might cause discomfort.
- D. 2 inches, 16 gauge: This needle is excessively long and thick for a deltoid injection, making it uncomfortable and unnecessary for this purpose. Such a large gauge is generally used for procedures requiring the rapid infusion of fluids or blood.
In summary, the 1-inch, 23 gauge needle (Option B) strikes the right balance of length and gauge for administering 2 mL of viscous fluid into the deltoid muscle, ensuring effective delivery while maintaining patient comfort.