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Year : 2022  |  Volume : 54  |  Issue : 4  |  Page : 253--257

A retrospective review of a 2-year strong antimicrobial stewardship program in a tertiary care institute in Mumbai

Sanjith Saseedharan, Nausheen Shaffi, Sonal Rambhad, Vaijyanti Kadam, Elizabeth J Mathew 
 Department of Critical Care, S.L. Raheja Hospital - A Fortis Associate, Mahim, Mumbai, Maharashtra, India

Correspondence Address:
Dr. Sanjith Saseedharan
S.L. Raheja Hospital Mahim, Mumbai, Maharashtra


BACKGROUND INFORMATION: Many institutes have implemented a strict antimicrobial stewardship (AMS) program in the postantibiotic era. AIM: To investigate how the resistance pattern changes after implementation of a stringent AMS programme. METHODOLOGY: It employs a defined daily dose methodology (DDD). The formulae listed below are used to compute this for two periods: October 2015 to October 2017 (Period 1) and October 2017 to October 2019 (Period 2) (Period 2). DDD = Antibiotics used in total (g) per year [INLINE:1] The length of stay was determined using the data from the hospital's information system (HIS). The patterns of resistance to the limited antibiotics are vancomycin, linezolid, tigecycline, and colistin. In both Periods 1 and 2, skin and soft-tissue infections, urinary tract infections, bloodstream infections, and respiratory tract infections were studied in both periods. RESULTS: In the year from October 2015 to October 2017, 4569 patients received limited antibiotics out of a total of 14,544 admissions. The average length of stay was 7.48 days in Period 1, however, it was reduced to 3.96 days in Period 2 out of 15,199 patients. In vitro isolate sensitivities to vancomycin, linezolid, tigecycline, and colistin were increased. CONCLUSION: Some of the most common antibiotics were used less frequently. This appears to be linked to a shorter stay in the hospital and increased antibiotic susceptibility.

How to cite this article:
Saseedharan S, Shaffi N, Rambhad S, Kadam V, Mathew EJ. A retrospective review of a 2-year strong antimicrobial stewardship program in a tertiary care institute in Mumbai.Indian J Pharmacol 2022;54:253-257

How to cite this URL:
Saseedharan S, Shaffi N, Rambhad S, Kadam V, Mathew EJ. A retrospective review of a 2-year strong antimicrobial stewardship program in a tertiary care institute in Mumbai. Indian J Pharmacol [serial online] 2022 [cited 2022 Nov 28 ];54:253-257
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Emergence of resistance to multiple organisms is a common threat to society. We all are living in a pan drug-resistant era, in which patients are getting resistance to all the types of antibiotics which cover both Gram-positive and Gram-negative bacteria.[1] There is a struggle for the clinician in choosing the antibiotics of critically ill patients. We are in the post antibiotic era where the pipeline for new classes of antibiotics is drying up.[2] By analyzing recent studies seems to reveal a close relationship between antibiotic use, resistance, and treatment cost. This points to the need of a strong antimicrobial stewardship programme.[3],[4] Defined daily dose (DDD) is a standard metrics approved by WHO to measure the consumption of antimicrobials in the hospital.[4],[5] We tried to study (if at all) the benefits of implementing a strong antimicrobial stewardship(AMS) program for patients, hospital and society.

The antimicrobial stewardship (AMS) program was launched by the collaboration of different departments in the hospitals including nurses, pharmacists, administrators and clinicians. Our study was classified into two phases, in which the first phase was the initial process of the program where awareness among the staff was very less and the second phase, in which there was an improvement in the program. Both of the phases, the Standard Metrics of WHO, defined daily dose was used to calculate the consumption of antibiotics in the hospitals. 14544 patient were admitted between October 2015 and October 2017. Among these 4569 patients received predefined restricted antibiotics which included (one ore multiple) carbapenem group including doripenem, imipenem-cilastatin, ertapenem, meropenem,vancomycin, tigecycline,tecoplanin, linezolid, daptomycin, fosfomycin, colistin, polymyxin B, amphotericin, anidulafungin, caspofungin and micafungin. The total length of stay was 34184 days with an average length of stay of 7.48 days. During the second period (October 2017 to October 2019) the total number of admissions were 15199 of which 9552 patients received restricted antibiotics. The total length of stay was found to be 37853 with an average length of stay of 3.96 days per patient. There was a difference of 3.5 days in the average length of stay which would relate to large cost savings as seen by Nathwani et al.[6]

It was surprising to note a rise in the sensitivity of vancomycin, linezolid, tigecycline, colistin.


This retrospective study was performed by collecting data using the hospital information systems from two periods October 2015 to October 2017 (not including the month of October 2017) hereby called period 1 and October 2017 to October 2019 (not including October 2019) hereby called period 2. At the end of period 1, we formed a antimicrobial stewardship working group which included Clinical Microbiologist physician, Clinical Pharmacist, Intensivist, and the Medical Superintendent. Sixteen Antimicrobials were classified as restricted antimicrobials. The AMS Forms was framed to be filled by the consultant/Registrars after prescription of each restricted antibiotics. The AMS form needed.[1] Justification for the prescription of these restricted antibiotics.[2] Whether site specific cultures were sent. Pharmacy would not dispense the third dose of the medicine if there was no justification in the AMS form. This form was then evaluated by microbiologist. The pharmacologist confirmed the dose, route and drug prescribed. Further the intensivist along with the microbiologist reviewed the cultures and then discussed with the prescribing physician for de escalation or escalation if required.

Process design

Antibiotics stewardship working group included Pharmacist, Infection Control Nurse (ICN), Microbiologist and intensivist and medical superintendent. Hospital standard operating procedure was formed for Antimicrobial stewardship program and signed off by the above stakeholders from the working group. A justification form was made, in which clinicians need to justify the use of antibiotics. Ten antibiotics were classified as 'Restricted Antimicrobials' based on their spectrum, mode of action and efficacy.

Process awareness

Various awareness programs were initiated by medical administrators by the collaboration of clinicians, nurses, and pharmacists for the awareness of the AMS program.

Process implementation

Prescribed antimicrobials are reviewed for appropriateness by the clinical pharmacist regarding dose, therapeutic duplication, and ensuring the drug reached the patient. Pharmacy were given a privilege to stop dispensing of the drugs if they do not receive the justification (AMS from) form, with the support of the management. The form was further shared with the intensivist. After discussion the intensivist would approach respective clinicians for escalation and de-escalation. In case of any discrepancy or non compliance matters would be escalated to the medical superintendent and any gaps in the process were discssed every 3 months.

Process analysis

The research was divided into two time periods: October 2015 to October 2017 and October 2017 to October 2019.

For two periods, the DDD was estimated using the formulae listed below.


The hospital information system (HIS) was used to calculate the length of stay (HIS). The patterns of resistance to antibiotics vancomycin, linezolid, tigecycline and colistin, in both periods 1 and 2 were investigated for isolated from skin and soft tissue infections (SSTI), urinary tract infections (UTI), blood stream infections (BSI), and respiratory tract infections (RTI).


Data collection

All data were collected from the online hospital information system. Justification for the use of these antibiotics was verified. The forms were sent to the intensivist for further analysis, the restricted antimicrobial folder is made in the hospital software and all the details of restricted antibiotics receiving patients are daily cross-checked by ICN. All the data regarding the number of admissions and patients with restricted antimicrobials were collected from HIS. Antibiogram data were collected from the microbiology department.

Length of stay

There were 655 more patient of admitted in the period 2 as compared to period 1. Length of stay in period 2 was found to be 3.5 days lesser compare to period 1.

Calculation metrics

A defined daily dose was used as the metrics for the calculation to identify the total use of antimicrobials. It was done accordingly as per WHO definition.[4],[5] All the restricted antibiotics consumption was taken from the HIS. All 16 antibiotics were analyzed as per the equation. It was found that most of the consumption was come down in the second period of the study. The demographic data are shown in [Table 1]. We attempted to study length of hospital stay and amount of drugs used by calculating the DDD as shown in [Table 2].{Table 1}{Table 2}

Sensitivity pattern

The sensitivity pattern of selected antibiotics such as linezolid, vancomycin, tigecycline, and colistin was studied during these periods [Graph 1],[Graph 2],[Graph 3],[Graph 4]. It was found that there was a commensurate rise in the sensitivity of linezolid and vancomycin toward SSTI. Tigecycline, colistin sensitivity also improved for isolates from RTI, UTI, BSI, and SSTI during period 2. The protocol for AMS is given in the figure. We attempted to study the length of hospital stay, amount of drugs used by calculating the DDD, the total number of admissions, and sensitivity pattern to selected antibiotics such as linezolid, vancomycin, tigecycline, and colistin.[INLINE:2][INLINE:3][INLINE:4][INLINE:5]


The consumption of antibiotics did reduce as was evident by the DDD calculated indicating one of the prime success of the antimicrobial stewardship programme and as every AMS programme published in literature this also would have translated into reduced cost.[7] There is a casual relationship between antimicrobial use and resistance.[8] The main goal of AMS is to optimize the therapy to ensure the judicious use of these antibiotics and the secondary goal is to reduce the cost of the therapy.[9] Other additional benefits on the AMS is that it will directly reflect the hospital resistance pattern. This study raises concern about the use of antibiotic patterns in the hospital. On our assessment, we found that strict implementation in the program may improve patient outcomes as well as over utilizations.[10],[11] It can improve the quality of patients, which decreases hospital stay and can make mentally more comfortable to the patient.

Our study does not cover case mix, in which there is a co-relationship between case mix and AMS.[12] Apaches were not followed in our case. There is no data regarding in the readmission of the patient using antimicrobials in the hospitals.[6] De-escalation cannot be a measure for quality indicators in the hospital. Colistin micro broth dilution was not done in our study which will show accurate results.[13]

However, there was an increase in the use of meropenem and polymyxin B in the second period compared to the first period. Recent guidelines advocated combination therapy of HD colistin and HD meropenem.[14],[15]

The increase in the sensitivity pattern indicates that a strong AMS program does help in the menace of the post antibiotic era and thus may also relate to a chance for better treatment among our patients of sepsis. Further research should focus on microorganism-wise improvement in hospital-acquired infection and should also consider the Clostridium difficile infection rate.


The AMS programme needs considerable effort and collaboration between many hospital departments. Apart from lowering antibiotic consumption, implementation of a strong antimicrobial stewardship programme seems to a shorten the duration of hospital stay and increase sensitivity to antimicrobials.


Apaches and case mix were not followedColistin micro broth dilution was not done.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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