The nurse anticipates use of an extended-spectrum penicillins such as piperacillin when the patient ...

Correct Answer: 3
Rationale 1: Extended-spectrum penicillins are effective against strep, but this is not their advantage.
Rationale 2: Extended-spectrum penicillins are not effective against herpes, a virus.
Rationale 3: Extended-spectrum penicillins have as their advantage antimicrobial activity against Pseudomonas.
Rationale 4: Extended-spectrum penicillins are effective against staph, but this is not their advantage.
Global Rationale: Piperacillin and ticarcillin have broad spectrums of antimicrobial activity similar to those of the aminopenicillins. Their primary advantage is their additional activity against Pseudomonas aeruginosa; thus they are called extended-spectrum or antipseudomonal penicillins.