THERAPEUTIC DRUG MONITORING OF ANTIMICROBIALS BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY IN CRITICALLY ILL PATIENTS

BACKGROUD: The burden of infection is high in the intensive care unit (ICU) even after the consumption of antimicrobial agents (antibacterials, antifungals and antivirals). Hence, it is essential to optimise the use of antimicrobial agents not only to maximize therapeutic success but also to prolong the lifespan. For optimum clinical efficacy, Therapeutic drug monitoring (TDM) can be done which is the clinical practice of measuring specific drugs at designated intervals to maintain a constant concentration in a patient’s bloodstream, thereby optimizing individual dosage regimens. TDM also helps to review pharmacokinetics (PK) and pharmacodynamics (PD) of antimicrobials which can limit the emergence of resistance.  OBJECTIVE: 1. To identify the most commonly used antimicrobials in ICU. 2. To do therapeutic drug monitoring of antimicrobials by HPLC thereby estimating the plasma concentration of the given drug 3. To describe how TDM can be utilized to improve critically ill patient outcomes from severe infections**MATERIALS AND METHODS:**This study will be initiated after approval from IEC. Written informed consent will be obtained. STUDY POPULATION: patients admitted in ICU above 18 satisfying inclusion and exclusion criteria. SAMPLE SIZE: 100 calculated using sample size & statistics software based on previous study. STUDY SITE: Melmaruvathur Adhiparasakthi Institute of Medical Sciences And Research STUDY DURATION: 3 years **STUDY CHEMICALS:**Will be purchased from HI-MEDIA, SIGMA ALDRICH, MI.**INSTRUMENTATION AND CHROMATOGRAPHIC CONDITIONS:**Shimadzu HPLC CBM-20A SAMPLING TIME: TDM with two samples drawn at 1 (30-mins post completion of drug infusion) and 6–22 hours post administration **SAMPLE PREPARATION AND VALIDATION:**will be done as per the instrument manual. Specially designed case proforma will be used to collect all the relevant data.  STATISTICAL ANALYSIS: HPLC allows description of peak concentrations and AUC using linear regression. The results will be tabulated and analyzed using SPSS 22.0. **CONCLUSION:**This research willprovide a practical guide on how TDM can be applied in routine clinical practice to improve therapeutic outcomes, thereby minimizing the risk and toxicity in critically patients KEYWORDS: TDM, Antimicrobials, Pharmacokinetics, Pharmacodynamics