Population Pharmacokinetics of Levofloxacin in Plasma and Bone of Patients Undergoing Hip or Knee Surgery.

Patients undergoing hip or knee replacement therapy are routinely pretreated with antibiotics before they enter the operation theater. This treatment intends to reduce the incidence of peri- or postsurgical infections. Here, we calculated the uptake kinetics of levofloxacin into bone to see whether levofloxacin could be obtained from the trabecular and cortical bone and at what time concentrations are sufficiently high to inhibit the usual hospital infections. Patients (n = 42) undergoing routine surgery were treated with 500 mg levofloxacin intravenously immediately prior to the operation. Plasma samples were taken before and at 3 points after termination of drug infusion. After replacement of the bones, extracts were obtained from them. Levofloxacin was quantified using high-performance liquid chromatography. The kinetics of levofloxacin and its distribution into bone were analyzed using a population approach (ADAPT5). Clearance was 14.0 L/h, and distribution volume was 77 L. Bone uptake t½ was calculated as 4.2 and 5.4 hours for cortical bone and trabecular bone, respectively. In knee samples (but not in hip samples), we noted that the cortical bone contained higher levels of levofloxacin than the trabecular bone. From our data, we can conclude that levofloxacin might be useful for prophylactic use in bone surgery.

Perspectives About Personalization for mHealth Solutions Against Noise Pollution.

Noise harms the environmental quality and can have negative effect on health and wellbeing. Providing silent areas and periods of rest is one way to improve the perceived environmental quality. However, realization is not easy in the day to day life. The usage of mHealth solutions which can provide information about the sound of a certain area and the respective effect on humans could be supportive. As the perception of sound is highly subjective, the prediction of the perceived acoustic environments is very difficult. This paper describes a course of action to develop an automatic estimation of an acoustic environment, based on the measurement of sound properties solely. The challenges of this endeavor are explained in detail. Possible application areas in mHealth are identified and presented. This future vision paper wants to draw the attention to different possibilities to cope with noise pollution either by personal behavior change or by using personalized data to reach out for a more general applicability for example through soundscape.

Pharmacokinetics of ceftriaxone in plasma and bone of patients undergoing hip or knee surgery.

OBJECTIVES: Patients undergoing hip or knee replacement therapy are routinely pretreated with antibiotics before surgery. It is controversial in which antibiotic is the treatment of choice for this purpose. One possibility is the cephalosporin ceftriaxone. Here, we wanted to know if effective tissue concentrations are reached. METHODS: We studied plasma and bone kinetics of ceftriaxone in orthopaedic patients (n = 22) treated with ceftriaxone (2 g) immediately prior operation. Plasma samples were withdrawn before and at three time points after ceftriaxone infusion. After bone replacement, extracts from cancellous bone or cortical bone were obtained, and ceftriaxone was quantified using column chromatography. KEY FINDINGS: The plasma kinetics of ceftriaxone and distribution into bone were analysed using a population approach (ADAPT 5). The population mean of the area under the curve (AUC) was 140 mg h/l. A cancellous bone to plasma concentration ratio of 1.12 ± 1.29 was achieved 5 h after start of infusion. The half-life of uptake into the cortical bone was less (8.4 h) than into cancellous bone (12.1 h, P < 0.05). CONCLUSIONS: Under these experimental conditions, concentrations of ceftriaxone in cancellous and cortical bone should be adequate to protect the patients against usual ceftriaxone-sensitive nosocomial infections and are substantially lower than the plasma concentrations.