When should prophylactic antibiotics be infused for a procedure involving a pneumatic tourniquet?

Prophylactic antibiotics should be infused before the tourniquet cuff is inflated to ensure optimal effectiveness in preventing infections. Administering the antibiotics prior to inflating the cuff allows for adequate tissue levels of the medication to be achieved. This timing is essential because once the tourniquet is inflated, blood flow is occluded, which can delay the distribution and absorption of the antibiotic within the tissues that are at risk of infection during the procedure. Starting the antibiotic prophylaxis early ensures that the protective effects of the medication are in place before any potential exposure to pathogens occurs during the surgical intervention.

Considering the context of the other options, infusing antibiotics after the cuff is inflated, during the procedure, or once the procedure is completed would not provide the necessary protective coverage when tissues are at highest risk of contamination. Thus, the timing of the antibiotic administration in relation to the tourniquet inflation is crucial for achieving effective prophylaxis against postoperative infections.