Background & objective: The prevalence of antibiotic resistance has increased with the excessive use of antibiotics in our country. We aimed to examine the patterns of antibiotic resistance in different organisms found in patients admitted to our Medical Intensive Care Unit (MICU). Additionally, the study sought to determine the relationship between the pathogen causing the infection and the outcome of the patients. Methodology: This retrospective observational cross-sectional study was conducted in the MICU of Farooq Hospital affiliated with Akhtar Saeed Medical College, Rawalpindi, Pakistan, from January 01, 2024 to March 31, 2024. The data was collected from the medical records of adult patients (aged 12-79 y) who were admitted to the MICU during the study period. SPSS 29 was used for data analysis. Analyzed data included information on demographics, culture results, and antibiotic resistance patterns. We included culture results of blood, urine, and Foley catheter tip. The final disposal of the patients was noted and linked to the pathogen responsible for the disease. Results: The study involved 104 patients admitted to the MICU. The average duration of stay was 5.36 days, the average age was 51.17 ± 18.47 y, and 61.53% of the patients were male. The primary diagnoses were urinary tract infection (18.22%) and sepsis (15.76%). Pre-existing conditions included diabetes mellitus (24.15%) and hypertension (23.59%). Klebsiella pneumoniae was the predominant organism, followed by E. coli. Overall, 58.52% of the isolates showed resistance to the tested antibiotics. Specific drugs, such as ceftazidime and amoxicillin-clavulanic acid, demonstrated absolute resistance (100%), while vancomycin and tigecycline showed no resistance. In this study, patients with infections caused by Enterobacter, Enterococcus faecalis, Proteus, and Salmonella spp. had discharge rates of 100%. In contrast, infections caused by Candida, Acinetobacter species, and Klebsiella pneumoniae were associated with 100%, 75%, and 48.5% mortality rates, respectively. Conclusion: The study revealed a significant prevalence of antibiotic resistance among microorganisms in our Medical Intensive Care Unit. Klebsiella pneumoniae was the predominant organism, and distinct bacterial infections were linked to diverse patient outcomes. Abbreviations: MDR - multidrug resistance; MICU - Medical Intensive Care Unit; MRSA - methylene resistant S. aureus XDR - extensively drug resistant Keywords: Antibiotic, Resistance, Pakistan, Intensive Care Units. Citation: Bacha MF, Sayed TM, Maqsood J, Noaman M, Aslam M, Noureen F, Ikram N. Antimicrobial resistance patterns in patients admitted in a medical intensive care unit at Rawalpindi, Pakistan. Anaesth. pain intensive care 2024;28(4):727−731; DOI: 10.35975/apic.v28i4.2521 Received: June 10, 2024; Reviewed: June 21, 2024; Accepted: July 15,2024