Question 4

The maximum depth of the lancet for a dermal puncture on an infant should be 2 mm.

Using a lancet depth of 2 mm is appropriate for dermal punctures on infants to minimize the risk of injury to deeper tissues while still obtaining an adequate blood sample.

A) 3 mm

A maximum depth of 3 mm is too deep for a dermal puncture on an infant. This depth increases the risk of hitting underlying structures, which can lead to complications such as excessive bleeding or infection.

B) 2 mm

A depth of 2 mm is the recommended maximum for a dermal puncture on an infant. This depth is sufficient to collect the necessary blood sample while ensuring the safety of the procedure by avoiding damage to underlying tissues.

C) 0.30 mm

A depth of 0.30 mm is insufficient for a dermal puncture, as it may not penetrate the skin adequately to obtain a blood sample. This depth could lead to failed attempts and unnecessary discomfort for the infant.

D) 0.20 mm

A maximum depth of 0.20 mm is also inadequate for a dermal puncture. Similar to 0.30 mm, this depth would likely not reach the capillary bed, resulting in insufficient blood collection and potential repeated punctures.

Conclusion

The correct answer, 2 mm, is critical for safely performing a dermal puncture on an infant, balancing the need for an effective blood sample while minimizing the risk of complications. Options A, C, and D fail to meet the necessary standards for safety and efficacy, while Option A exceeds the recommended depth, posing unnecessary risks.