KEYWORDS: Antimicrobial stewardship; Culture-guided prescriptions; Emperical treatment; Surgical ward

INTRODUCTION

Antimicrobial treatment is crucial in preventing severe complications and mitigating the devastating consequences of various infections. However, the prescriptions are frequently administered empirically to provide broad coverage against Gram-positive and Gram-negative infections in surgical and non-surgical procedures.1,2 The indiscriminate use of broad-spectrum antibiotics poses additional challenges, including antibiotic misuse, unnecessary antibiotic-related side effects, increased antimicrobial resistance, and inflated treatment costs for hospitalized patients.3,4 The escalating bacterial resistance poses a significant challenge, exacerbated by a decline in the discovery of new antibiotics. In India, hospitals are witnessing alarming resistance levels to quinolones and carbapenems. Additionally, the utilization of last-resort antibiotics such as polymyxins has surged, alongside documented rises in resistance levels within healthcare settings. Consequently, there is a growing emphasis on implementing antimicrobial stewardship programs (AMSP) to promote judicious antimicrobial use.5,6 Among various AMSP interventions, culture-guided prescription is a major de-escalating one.

Hence, the objective of this study was to delineate the antibiotic prescription patterns among patients admitted to surgical wards and intensive care units (ICU) and also evaluate the frequency with which clinicians requested specimen cultures during patients’ hospitalization.7

METHODOLOGY

This retrospective observational study was carried out at the 750-bed tertiary care centre of North India, spanning the duration of eight months, from June 2023 to January 2024. All consecutive patients on parenteral antibiotics admitted to the Surgical Wards and ICUs were enrolled. Baseline characteristics, including age, gender, duration of stay, and outcome, were documented for each patient.

 The centre operates a 24-hour Microbiology laboratory equipped with an automated bacterial culture system (Bact Alert) and conducts antimicrobial susceptibility testing using the Kirby-Bauer disk diffusion method. An infection control nurse from the hospital conducted an audit to assess the types, numbers, and durations of antibiotics administered to each patient until discharge. Concurrently, the details regarding whether any samples were sent for culture and the results of those cultures, if available, were recorded. The hospital utilizes a fully operational hospital information system and indigenously developed software for data entry and reporting in microbiology laboratory. 

Patients who received antibiotics based on culture and sensitivity results were categorized as having received appropriately prescribed antibiotics. In contrast, those who did not match these criteria were classified as having received inappropriately prescribed antibiotics.

Ethical permission: Ethical permission was obtained from the Institutional Ethical Board  AIIMS, Gorakhpur (IHEC Ref no-IHEC/AIIMSGKP/BMR/164/2023dated-20/05/2023).

RESULTS

This study included 1018 consecutive patients admitted to the surgical wards (General Surgery, Otorhinolaryngology, Obstetrics & Gynaecology, Orthopaedics, Ophthalmology) and ICU. The baseline characteristics of the patients are outlined in Table 1. 

Table 1– Baseline characteristics of patients admitted to the hospital from June 2023- January 2024

The study observed a predominance of male patients, with 854 individuals (83.8%) and age group 21-40 years (52%). Overall, confirmed infections through culture were identified in 255 patients (25%). Gram-negative bacteria were more prevalent, accounting for 240 cases (94.2%), compared to Gram-positive bacteria, which were present in only 15 cases (5.8%). 

This difference was found to be statistically significant (P < 0.001). The most common organism isolated was Escherichia coli 197 (72.2%), followed by Klebsiella pneumoniae 26 (10.19%), Pseudomonas aeruginosa 15(5.8%), Staphylococcus aureus 11 (4.3%), Enterococcus spp 4 (1.5%) and Proteus spp. 2 (0.7%). A total of 2850 antibiotic prescriptions were made for the 1018 patients, i.e., an average of 2.79/group antibiotics/patient included in the study. The most commonly used antibiotic was cephalosporins, administered to 913 patients (89.7%), followed by aminoglycosides, prescribed for 756 patients (74.3%), metronidazole for 492 patients (48.4%), and piperacillin-tazobactam for 353 patients (34.7%). Twelve patients (1.2%) did not receive antibiotics, while 188 (18.5%) received monotherapy. Additionally, 530 patients (52%) were treated with two to four antibiotics, and 288 patients (28.3%) received more than five antibiotics during their hospital stay.

Among the total admitted patients, microbial culture yielded positive results in 255 individuals (25%), negative results in 458 individuals (45%), and samples were not sent for culture in 305 individuals (30%). This may be due to clinical decisions based on the patient’s stable condition, logistical issues, and empirical treatment decisions without microbiological confirmation. Among those with positive cultures, appropriate antibiotics, i.e., those matching the culture sensitivity report, were prescribed to 106 patients (41.5%), while inappropriate antibiotics were administered to 149 patients (58.5%). This difference was found to be statistically significant (P < 0.001). The duration of hospital stay was primarily less than 15 days for 86% of the total admitted patients. This was followed by hospitalizations lasting between 16 to 30 days, accounting for 11.7% of patients, while 2.3% required a hospital stay exceeding one month.

DISCUSSION

This study focuses on regulating the frequency with which antimicrobial prescriptions fall in together with culture-based reports. We found that antibiotic prescriptions predominantly relied on empirical choice; adjustments to antibiotics post-initiation were infrequent.

This study emphasized that 41.5% of antibiotics were prescribed on culture-based reports. In contrast, antibiotics were prescribed in 58.5% of cases without depending on culture-based reports due to clinical judgment, logistical issues, and empirical treatment preferences. These findings were similar to a study stating that antibiotics were empirically administered in 64% of cases, while in the rest, they were administered after microbiological confirmation.8

In the present study, it was observed that Gram-negative bacteria were predominant at 94.2%, which was similar to a study in which infections instigated by Gram-negative organisms surpassed Gram-positive organisms in frequency.9 Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus spp and Proteus spp were our study’s most common isolated organisms.

To handle this non-compliance to culture-guided prescriptions, attention should be directed towards educating medical students, post-graduate trainees, pharmacy students, and residents on established principles of antimicrobial stewardship. Hospitals in India must promptly establish antibiotic policies due to the widespread challenge of antimicrobial resistance. Crucially, there is a necessity to develop stringent antibiotic restriction policies and enact protocols for antibiotic utilization to streamline the judicious use of antimicrobials.10,11 

Clinicians prescribing antibiotics must ensure that the initial antibiotic selection aligns with the hospital’s antibiogram and undergoes continuous evaluation as part of antimicrobial stewardship efforts. Routine audits and feedback assessments serve as effective mechanisms for monitoring irrational antibiotic usage in both ward and intensive care unit settings. Educating antibiotic prescribers is fundamental to the success of any antibiotic stewardship program, and imparting guidelines and clinical pathways will significantly enhance antimicrobial prescribing practices.

There are few limitations to the study: retrospective in nature, single center dependent, single nurse collecting the data prone for selection bias, antibiotic audit by microbiologist without clinician and pharmacologist inputs, and lack of comparison with culture negative empirical treated patients with their outcomes.

CONCLUSION

This study found culture-confirmed infections in 25% of patients who had received antibiotics in surgical wards and ICUs. Notably, 58.5% of patients with positive cultures received inappropriate antibiotics (P < 0.001). These results highlight the need for better AMSP and adherence to culture sensitivity to improve treatment efficacy, patient outcomes, and reduce inappropriate antibiotic use. 

ACKNOWLEDGEMENT

We thank all other contributors and the technical staff for helping us with the final data analysis.

CONFLICTS OF INTEREST STATEMENT 

The authors declare no conflict of interest. 

SOURCE OF FUNDING 

None 

AUTHOR’S CONTRIBUTION

PS: Conceptualization; Data curation; Analysis; Writing the draft; Investigation; Methodology

KA: Analysis; Writing the draft; Methodology

ARR: Validation; Review & Editing

VH: Validation; Review & Editing

AM: Supervision; Validation; Review & Editing

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