Ertapenem (Invanz) is an intravenous carbapenem antibiotic. Compared to meropenem, ertapenem has a more limited spectrum of activity, notably lacking activity against Pseudomonas, Acinetobacter, and Enterococcus – some very important healthcare-associated organisms. Furthermore, it’s not an excellent option for penicillin-resistant pneumococci.
Although I rarely use this antibiotic in my OR and ICU practices, a surgeon may ask for this because of its long half-life (daily administration rather than q6h or q8h) and broad-spectrum activity against gram-positive bacteria, gram-negative bacteria, ESBLs, and anaerobes with the exceptions noted above.