What are the treatments for Bacteremia in ICU settings?

From the Guidelines

Bacteremia treatment in ICU settings should involve administering beta-lactam antibiotics through continuous or prolonged infusion to maximize bacteriological and clinical responses.

Key Treatment Strategies

• Personalized medicine: Administering beta-lactam antibiotics based on the patient's specific needs, taking into account the many sources of pharmacokinetic (PK) variability in the ICU population 1.
• PK-PD target: Aiming for a free plasma concentration between four and eight times the minimum inhibitory concentration (MIC) of the causative bacteria for 100% of the dosing interval to maximize bacteriological and clinical responses 1.
• Continuous or prolonged administration: Using continuous or prolonged administration of beta-lactam antibiotics in severe patients, in cases of high MIC bacteria, and in cases of lower respiratory tract infection to improve clinical cure 1.
• Therapeutic drug monitoring (TDM): Utilizing TDM to improve PK-PD target achievement and ensure effective treatment 1.

Recommended Antibiotic Administration

• Beta-lactam antibiotics: Administering beta-lactam antibiotics, such as cefepime, piperacillin-tazobactam, meropenem, and doripenem, by intravenous infusion for 3 or 4 hours to treat severe infections, especially if the identified bacteria have high MICs 1.
• Vancomycin: Administering vancomycin by continuous infusion, after a loading dose, to reach early target plasma concentrations, which are determinant for its efficacy 1.

General Principles

• Early administration: Administering effective intravenous antimicrobials within the first hour of recognition of septic shock or severe sepsis without septic shock 1.
• Empiric therapy: Using initial empiric anti-infective therapy that has activity against all likely pathogens and penetrates in adequate concentrations into tissues presumed to be the source of sepsis 1.
• De-escalation: Reassessing the antimicrobial regimen daily for potential de-escalation and discontinuing empiric antibiotics when no evidence of infection is found 1.

From the Research

Treatments for Bacteremia in ICU Settings

• The most commonly used antibiotics for the treatment of bacteremic patients throughout the 1970s were amoxicillin and gentamicin, but after the introduction of cephalosporins in the early 1980s, their use increased progressively 2.
• For management, the majority of the patients were prescribed teicoplanin (58.7%) in a study conducted in 2016 3.
• Different strategies have been advocated to optimize the efficacy of empirical antibacterial treatments, including de-escalation therapy and pre-emptive therapy, as well as measurement of pharmacokinetic and pharmacodynamic (pK/pD) parameters for proper dosing adjustment 4.
• The carbapenems are potent parenteral antibiotics, with an ultra-broad spectrum of activity that encompasses multi-drug resistant and difficult-to-treat Gram-negative bacteria, and clinical trial data supports their clinical effectiveness in patients with difficult to treat pathogens 5.

Antibiotic Resistance and Treatment

• Gentamicin resistance of gram-negative organisms has not increased during a 25-yr period, despite being one of the most frequently prescribed antibiotics in the ICU 2.
• The appearance of new multiresistant pathogens has determined the use of new antibacterials, the reintroduction of other drugs that have been removed in the past due to toxicity, or the use of combinations with in vitro synergy 4.
• The emergence of more sensitive microbiological techniques and increased knowledge about interactions between critically ill patients and their microbiota are leading to a rethinking of how to define HAIs and best strategies to diagnose, treat, and prevent these infections in the ICU 6.

Patient Outcomes and Mortality

• The 28-day overall mortality rate in a study of Gram-positive bacteremia was 52.9% 3.
• Independent risk factors like diabetes mellitus, central line insertion, and acute pancreatitis in adult patients with Gram-positive bacteremia were associated with higher mortality 3.
• The administration of early appropriate antibiotics improves patient outcomes 3.