Paracetamol

Pharmacokinetic evaluations will be conducted to characterize the cefazolin plasma concentration-time profile, cefazolin penetration into subcutaneous adipose tissue, and paracetamol metabolization as assessed through blood sampling. The study population consists of children aged 2 to 15 years with either normal weight or overweight. All participants are admitted for a minor elective surgical procedure and will receive paracetamol and/or cefazolin as part of standard perioperative care. During the procedure, multiple blood and tissue-fluid samples will be collected to quantify paracetamol and cefazolin concentrations in the bloodstream, as well as cefazolin concentrations in subcutaneous adipose tissue. The study aims to characterize drug concentration-time profiles in blood (paracetamol), plasma (cefazolin), and adipose tissue (cefazolin), and to compare these pharmacokinetic parameters between normal-weight and overweight children. These data are essential to determine whether standard dosing regimens provide adequate drug exposure across different weight categories. Previous research indicates that achieving specific target concentrations in blood and tissue is necessary for optimal therapeutic effect, yet uncertainty remains regarding appropriate dosing in overweight children.

Emergency laparotomy is a high-risk procedure often performed in patients with severe physiological derangements due to sepsis, making perioperative management challenging. Although multimodal analgesia is essential, options are often limited by factors such as hemodynamic instability, renal dysfunction, and coagulopathy. Intravenous paracetamol is commonly recommended for perioperative analgesia because of its opioid-sparing effect, but evidence suggests it may cause hypotension through peripheral vasodilation, particularly in critically ill patients. Most data on this effect come from observational studies, and evidence regarding its intraoperative hemodynamic impact remains limited.