For several years, open abdomen with temporary abdominal closure using Negative Pressure Therapy (OA/NPT) has become one of the leading strategies to treat or prevent intra-abdominal hypertension in critically ill surgical patients after a wide range of complex abdominal injuries and conditions.

According to current practice, piperacillin-tazobactam (PTZ) is widely used as part of empirical combined antibiotic therapy to treat severe abdominal infections in the critically ill patients. On the other hand, little is known about the impact of OA/NPT on antibiotics pharmacokinetics and pharmacodynamics (PK/PD) and the optimal dosing regimens in this population remain unclear.

As PTZ is a small hydrophilic molecule with a very low level of protein binding, invesitigators hypothesized that OA/NPT should lead to significant changes in volume of distribution (Vd) and/or drug clearance (CL

The main objective of this study was to assess the incidence of underdosing and the pharmacokinetics of piperacillin in critically ill patients with OA/NPT.

The secondary objective was to assess the appropriateness of recommended regimens for empirical minimum inhibitory concentration (MIC) coverage.

Inclusion Criteria:

• Age ≥ 18
• Admitted in surgical ICU for a suspected length of stay > 3 days
• Receiving an antimicrobial therapy by PTZ
• For an intra-abdominal infection
• Under OA/NPT during antimicrobial therapy
• With urinary and arterial catheters

Exclusion Criteria:

• Severe renal failure (CLCR < 30 ml/min) without indication for continuous renal replacement therapy (CRRT)
• Known allergy to PTZ
• Patient's refusal for participation to the research
• Patient unable to consent (dementia or severe psychiatric disorders, people under legal protection, people deprived of their liberty...)
• Pregnancy or breast-feeding

Critically Ill Patients with Open Abdomen and Negative Pressure Wound Therapy