A prospective follow-up observational study to study and model the pharmacokinetics of the ceftriaxone free fraction in patients treated with high doses of ceftriaxone (greater than or equal to 4 grams per day). it is a pilot study that has between 10 and 20 patients. This study will not condition the treatment of patients at any time.~The samples will be processed after their extraction. The concentration of the samples will be analyzed using a high-performance gilent infinity liquid chromatograph coupled to a mass spectrometer using positive or negative ionization using electrospray.
Prospective observational follow-up study for the study and modeling of the pharmacokinetics of the free fraction of ceftriaxone in patients treated with high doses of ceftriaxone (greater than or equal to 4 grams per day).