Effects of blood loss and fluid volume replacement on serum and tissue gentamicin concentrations during colorectal surgery

Influence of pregnancy on ceftriaxone, cefazolin and gentamicin pharmacokinetics in caesarean vs. non-pregnant sectioned women

“…Because of ceftriaxone’s high and saturable binding to albumin, its free fraction varies with time, dose and albuminemia (31). Gentamicin binds to a small extent to plasma proteins (25, 37). Consequently, body‐fluid shifts may have a dramatic impact on gentamicin volume of distribution and serum drug concentrations (25, 37).…”

“…A large number of investigations have claimed greater efficacy by administering drugs prior to surgical incision, without exposing the infant to high antibiotic levels (12–17). Comparative studies of antibiotic prophylaxis show the same risk of infections (18–25).…”

“…The excellent concentrations in tissues (27), extremely low comparative cost (24) and lack of severe microbial resistance (24) have led to a high level of use of gentamicin for these purposes. It has a typical half‐life of 2–3 h, distributes quickly, mainly into extracellular space with an apparent volume of distribution of 0·25 L/kg, and binds to a small extent to plasma proteins (25, 37). Its use, however, is often limited because of its narrow safety margin and its relatively high incidence of nephrotoxicity (24, 37, 38) and ototoxicity (24, 37, 39).…”

Clinical practice guidelines for antimicrobial prophylaxis in surgery

“…Intraoperative redosing is needed to ensure adequate serum and tissue concentrations of the antimicrobial if the duration of the procedure exceeds two half-lives of the antimicrobial or there is excessive blood loss (i.e., >1500 mL). 17,41,94,[116][117][118][119][120][121] The redosing interval should be measured from the time of administration of the preoperative dose, not from the beginning of the procedure. Redosing may also be warranted if there are factors that shorten the half-life of the antimicrobial agent (e.g., extensive burns).…”

Influence of pregnancy on one-compartmental bio-metric blood loss calculations after cesarean section and gynaecological surgery

“…), and the other is by indirect measurement. The latter reflects blood loss through the assessment of haemoglobin (Hb) concentrations, haematocrit (Hct), the patient's blood volume, or the need for blood transfusions (1)(2)(3).…”