Question

a patient presents with high leucocyte esterase in her urine but is already on antibiotics. when should blood be drawn on this patient to perform a culture and sensitivity?
a) antibiotics should not influence the result of the blood c&s
b) no earlier than 7 days after the patient completes the antibiotic treatment
c) just before the patients next dose
d) as close as possible to the patient previous dose

Explanation:

When performing a culture and sensitivity (C&S) on a patient already on antibiotics, drawing blood just before the next dose (trough level) helps in getting an accurate result. Antibiotics can influence the C&S result. Waiting 7 days after treatment completion is not the standard practice for this scenario. Drawing close to the previous dose (peak - which is not the case here) or thinking antibiotics don't influence (they do) are incorrect.

Answer:

C. Just before the patient's next dose