An Antibacterial Drug Utilization Study at Surgical Units of Shree Sayaji General Hospital, Vadodara, Gujarat, India
P Bhabhor, H Hotchandani
P Bhabhor, H Hotchandani. An Antibacterial Drug Utilization Study at Surgical Units of Shree Sayaji General Hospital, Vadodara, Gujarat, India. The Internet Journal of Pharmacology. 2012 Volume 10 Number 1.
Antibacterials are among the most commonly prescribed drugs on a world wide basis. They account for nearly 20% of all new and repeat prescriptions each year. Each tertiary care hospital in the United States typically spends more than $ 1 million every year on the purchase of antibacterial drugs alone.Hence antibacterial as a group, contributes significantly to the cost of therapy. It is estimated that they account for over 50% of total value of drugs sold in India1. Keeping this in mind, it is not surprising that an increasing number of new antibacterial is being made available regularly. Not all of these massive uses can be justified. In fact, irrational prescribing of these drugs is known to take place throughout the world. In developing countries like India, this may be extremely important as the funds available for healthcare budget may be quite limited. Availability of large number of drugs in the market makes education of prescriber difficult which intricate the selection of a proper agent and may eventually increase cost and side-effects of drug treatment, bacterial resistance and most importantly patient mortality.
It has been observed that 64% of the total antibacterial prescribed are either not indicated or inappropriate in terms of drug selection or dosage. In many cases antibacterial are used without an appropriate bacteriological basis2.Similarly in in-patient setup, a major proportion (30-50%) of antibacterial drugsis prescribed for surgical prophylaxis. There are, however, several controversies in this matter, despite the fact that the general principles about this use have been published and are well known3.The fact remains that the injudicious use of antibacterial is very common in the hospitals. It is clear that if this can be improved, then misuse of antibacterial can be avoided to a large extent in a hospital setting. However before suggesting any change, it is necessary to evaluate the existing base line practice which can be done using data on prescriptions and prescribing practices with the help of a drug utilization study. This may therefore, help us to identify the problems, suggest the remedial measures and promote rational use4. So,to analyze the same at Shree Sayaji General Hospital (a tertiary level teaching hospital), Vadodara, Gujarat in six surgical units this study was carried out. Primary aim of the study was to evaluate the extent and pattern of use of antibacterial agents, in in-patients of six surgical units of Shree Sayaji General Hospital (SSG Hospital), Vadodara with secondary aim to determine the type of antibacterial used along with their purpose of use, route of administration, duration and supply.
Material And Methods
This was a prospective study with duration of 6 months from March, 2006 to August, 2006. Six units of general surgery with one ward for each of them were selected for the work. All the six units were covered by a single investigator one by one for eliminating observer bias. Fifty patients admitted to each unit during the time of the study were randomly selected for the work (using random table). Thus, a total number of 300 cases of indoor patients were studied. No patient was excluded from the study. The principle investigator visited the unit under the study thrice weekly and recorded all the relevant details of the case (s) in a pre-validated, predefined performa for a consequent analysis. The performa included the demographic profile of the patient, details of registration, diagnosis, date of admission, operation (if any) and discharge. Along with these, drug utilization details that included trade name of the drug(s), dose, route and frequency of administration, duration of treatment, indications (whether prophylactic or curative), source (hospital supply / market purchase) were also collected. Results of the culture and sensitivity tests if performed along with any other laboratory tests were also recorded. Adverse drug reactions were also monitored. The data obtained was analyzed for following prescribing indicators:-
Number and type of patients
A disease-wise distribution of 300 studied cases of indoor patients is shown in Figure-1 which represented a fairly broad cross section of general surgical problems presented to the surgical units of Shree Sayaji General Hospital, Vadodara, Gujarat.
Among 300 indoor patients, there were228 males (76%) as compared to 72 females (24%).Table 1 shows age wise distribution of indoor patients.
Use of antimicrobial Agents
Extent of use
It was observed that antimicrobial drugs were prescribed in all 300 indoor patients in surgery.
Type of antibacterial drugs in use
Route of Administration
Although no significant difference was observed in the antimicrobials prescribed by oral and parenteral route, yet out of the 1051 drugs prescribed, more no. of antimicrobials were given through oral route 53% (552) than through parenteral route 47%(499).
Purpose of Use
In 596(54%) out of 1051(100%) prescriptions, the use of antimicrobial agents was indicated for prophylaxis while remaining 482(46%) out of 1051 prescriptions the intention appeared to be curative for an existing or hospital acquired infections.
Out of 300 patients culture and sensitivity test was done only in 3.1% of cases only. Out of these, therapeutically modification was made in only one case, subsequently to the results of microbiological testing. It is thus clear that a laboratory support is hardly ever sought or taken in consideration for the antibacterial drug use in surgical patients particularly in a government setup.
Supply of Drugs
Out of 1051 total prescriptions, 86.6% (911) drug were supplied from government setup as compared to of 13.3% (140) drugs, which the patients were directed to buy from the market on account of non inclusion of these drugs in the government list of drug supply.
Drug utilization research is an essential part of pharmaco-epidemiology as it describes the extent, nature and determinants of drug exposure1. The World Health Organization (WHO) in 1997 defined drug utilization as the marketing, distribution, prescription and use of drugs in a society, with special emphasis on the resulting medical, social and economic consequences2.
Antibacterial drugs are life saving in many conditions. These drugs are the most widely used category of drugs in the world accounting for over one quarter of hospital drug costs5. These drugs have an important role to play in prevention and treatment of infections in surgical practice and now-a-days no surgical interventions are carried out without antibacterial cover. It has been observed that 30% or more of all hospitalized patients are treated with one or more courses of antibacterial therapy6. The use of antimicrobial is wide spread in industrialized countries. In the UK, one in every six prescription is for antibiotics. In Australia, antibiotics accounted for 17-20% of all the drugs prescribed. Antimicrobial being the most commonly prescribed groups of drugs the problem of its overuse is a global phenomenon. In India the prevalence of use of antimicrobial agents varies from 24 to 67%. Antibiotics as a group contribute significantly to the cost of drugs and are claimed worldwide to account for 15 to 30% of total health budget. It is estimated that in India, they account for over 50% of the value of drugs sold. The increasing overuse is associated with the development of antimicrobial resistance by the organism causing infection as well as adverse drug reaction caused by the use of antimicrobial. In several situations, the rational use of antibiotics has been reported to have reduced the emergence of resistant strains. Irrational prescribing of these drugs is known to take place throughout the world. In developing countries like India, this may be extremely important as the funds available for healthcare budget are quite limited.
This was a concurrent, qualitative drug utilization study wherein follow up of each patient was done right from admission to discharge and thereafter until the antimicrobial prescription continued. The inpatients included in the study represented a cross section of different patients of surgery. The study had revealed a number of interesting findings that are discussed below.
The most frequently administered group of antibiotics were cephalosporine 292(27.8%), amonoglycosides 185(17.6%) & nitroimidazole 183(17.4%). The other groups prescribed commonly were fluroquinolones 138(13.1%), penicillins 225(21.4%) and other groups 28(2.7%). The other group included cotrimoxazole, tetracycline and macrolides. All the indoor patients selected for the study received antibacterial drugs, irrespective of whether an operative procedure was carried out or not, or whether the patients had any impending infection which required treatment with antibiotics. Thus all patients received an antimicrobial drug at one time or the other. These figure are much higher than the other Indian studies which report the use of antibacterials in 20% to 67% of the patients only7,8,9. Similar studies in abroad indicate a range of 20% to 42% of patients received antibacterial drugs10. Several factors may be responsible for the higher rates of antimicrobial use in our study. Firstly, this work was conducted exclusively on inpatients where the necessity for antibacterial drug use may be perceived to be higher than the outpatients. However, as we discovered later on, that the use of antibiotics in indoor patients was more on account of relatively poor operation theatre conditions and a greater concern for hospital acquired infections. In this study we found that cephalosporins (27.8%), penicillins (21.4%), aminoglycosides (17.6%) and nitroimidazole (17.4%) were the most frequently prescribed group of antibiotics. While the other groups like cotrimoxazole, tetracycline, macrolides were prescribed less commonly.
On computing for prescribing frequency of individual antimicrobial drug, we found that the most frequently prescribed antimicrobial agents were cefotaxime (17.7%), metronidazole (17.4%) and gentamicin (13.8%). Other commonly prescribed antimicrobials were cefadroxyl (16%), ciprofloxacin (8.46%), ampicillin (4.66%), cloxacillin (9.41%), ceftriaxone (4.09%) and amoxicillin-clavulanic acid (3.09%).
Cefotaxime, cefadrodyl and ceftriaxone belong to the newer antimicrobials which have replaced the conventional group of penicillins to a greater extent, however cloxacillin, ampicillin and amoxicillin-clavulanic acid of penicillin group are almost equally used extensively. Metronidazole is used predominantly to cover up for all the anaerobic infections. While gentamicin has a wide gram- negative spectrum that includes pseudomonas aeruginosa and is the aminoglicoside of choice for most cases of hospital acquired aerobic gram negative sepsis. A long experience of its use and a relative low cost justify its position on top as has also been noted by Srishyla M. V.et al 199411. At the same time, easier availability in a hospital pharmacy may also dictate a rather heavy use of a particular drug.
Though our study had shown predominant use of cephalosporins, several Indian studies of this nature reported that the penicillin group of antibacterials were the most commonly prescribed drugs7,12,13.This could be due to a wider choice available in this group. Cephalothin sodium was most frequently prescribed in the surgical services, at Duke University Medical Center Ampicillin and cephalosporins were the most commonly prescribed drugs, at a general hospital in Pennsylvania14. The type of antibacterial use at each centre depends on many factors like the patient profile, type of infection, availability of antibacterials, susceptibility patterns, the prescriber’s awareness on rational antibacterial use, etc. Variations in the antibacterial susceptibility between different regions have been described and may result in different prescribing practices. Such statistics form an important index of ongoing antibacterial audit as they indicate the changes in the pattern of usage accordance with the susceptibility patterns of bacteria. They also indicate extent of use of newer antibacterial agents.
Number of antibacterial per prescription
Data analysis in our study showed that all the 1051 prescriptions with two or more antibacterial agents. This suggests that there was a trend to prescribe more than one group of antimicrobial drug per patient. A similar use of multiple antibacterial agents in orthopedics units for prolonged period has also been documented in other studies11.
One must remember that the risk : benefit ratio for each drug increases when multiple drugs are given. Extreme and persistent empirical treatment is one important cause of irrational antibacterial use. It is preferable to keep the number of drugs per prescription as low as possible, since, higher figures always lead to increased risk of drug – drug interaction. A study conducted in a hospital in Mumbai reported that prescriptions with single antibacterial agent were 48.7% and those with two or more antibacterial drugs were 51.3%9. Another study carried out in a tertiary care teaching hospital in Eastern Nepal reports that prescriptions with two or more antibacterial agents were 82.3% as compared to prescriptions with single antibacterial agent (17.7%)1. These figures are very close to the figures of our study. The poly-pharmacy, observed in this study, clearly indicates an excessive reliance on empirical therapy that itself may be a result of lack of awareness on the part of prescriber and an inadequate use of microbiological support.
Duration of antibacterial drug use
The average duration of treatment with antibacterial agents was 7.0 days in all the patients selected for the study which closely resembles duration of 6.6 days in separate study9. While a study conducted at general hospitals in Pennsylvania, the duration of treatment was 4.7 days which is much lower than our study. Prolonged use of antibacterial may alter the patients’ endogenous flora and favor the development or emergence of resistant strains or the acquisition of new strains with multiple antibacterial resistances16. This puts the patient at greater risk of developing an infection that is less amenable to standard therapy. Prolonged antibacterial therapy also increases the total cost of therapy. Prolonged use of antibacterial drugs reflects a casual attitude of the prescriber. Hence, it is important to emphasize the duration of treatment, particularly in infective disorders. Careful monitoring of prescription orders written daily can help prevent such unnecessary use.
Surgical prophylaxis accounts for a sizeable proportion of antibacterial use in surgical specialties. In the present study, 54% of all the patients studied were prescribed antibacterial agent for prophylaxis. However, it was observed that the antibacterial agents initiated for the prophylactic use were continued even after 24-36 hours without any evidence of infection. The purpose of surgical prophylaxis was therefore not served and this factor had in fact contributed to a large proportion of inappropriateness in antibacterial prescribing in the present study. In surgery, antibacterial agents are often used prophylactically and probably a minimum of two drugs are used to cover a wider range of microbes. For clean as well as contaminated major elective surgeries the incidence of wound infection can be decreased by the judicious use of proper prophylactic antibacterial to well below 2%17. The Indian study by Viswanathan et al reported a prophylactic antibacterial use in 43% cases and a 57% antibacterial use for therapeutic reasons7. The study conducted in general hospitals in Pennsylvania showed that about 60% of the cases were given prophylactic antibacterial agents for more than 2 days and the prophylaxis lost its purpose after 48 hours on the whole. Discontinuing prophylaxis 48 hours after the procedure may save about 20% of all antibacterial drugs used in hospitals. Several randomized trials have proved single dose prophylaxis to be as effective as multiple dose prophylaxis in most of the surgeries18,2. In spite of sufficient evidence, multiple dose prophylaxis is widely used as seen in our study. It is difficult to ascribe the exact reasons for this. It, however, appears that two reasons were important one was the unawareness about the rules of chemoprophylaxis and the other was a lack of faith in the general standards of asepsis in the hospital practices. Hence, surgical prophylaxis, an area of antibacterial usage, which is frequently abused and the consequences can be costly as well as dangerous, it calls for a continuous audit and review.
In the present study 53% of all the patients received antibacterial drugs orally and only 47% of the cases were given antibiotics parenterally. There was no significant difference observed in the route of administration preferred in the patients in our study. However, a study conducted at a tertiary care hospital in Bangalore reported that 61% of the patients received antibacterial agents orally11. Another study conducted in a tertiary care hospital in Eastern Nepal showed that the use of injectables was very high (a mean of 2.1 injectables per prescription) and 77.6% of the patients received the antibacterial drugs parenterally1. Parenteral use of drugs in general and antibacterials in particular is an important parameter to judge rational drug use. Unnecessary use of parenteral antibacterial adds to cost of therapy and also increases the risk of blood borne infections.
In the present study, culture and sensitivity tests were carried out in only 3.1% of the cases and the modification in treatment was made in only 0.8% of the patients. This indicates either unawareness or lack of faith or underutilization of microbiological services. A study on utilization of antibacterial drugs in a tertiary care hospital in Chandigarh showed that microbiological testing was performed in 42% of the cases15 same as in a separate study on antibacterial drugs usage in general hospitals in Pennsylvania showed that culture and sensitivity test was done in 69% of cases. These figures are also very high. Although the in-vitro activity of an antibacterial is not the only factor to be considered in deciding the therapy in an individual patient, yet the culture and sensitivity testing continues to be a useful tool, the judicious use of which can prevent therapeutic failures.
In any country a large number of socio-cultural factors contribute to the ways drugs are used. In India, these include national drug policy, illiteracy, poverty, use of multiple health care systems, drug advertising and promotion, sale of prescription drugs without prescription, competition in the medical and pharmaceutical market place and limited availability of independent, unbiased drug information. Last but not the least, on discussion with the surgeons about their point of view with regards to use of antibacterial in surgical practice; the following points were highlighted;
There was a lack of asepsis in the hospital in general and the operating rooms in particular.
Microbiology reports were unreliable. The department concerned, however reported that the collection / transportation and the delivery of the samples was improper.
Short supply of drugs in the hospital compels the prescriber to use alternatives that may not be the drugs of choice.
Hospital did not have a formulary or Drugs and Therapeutics Committee. This resulted into the lack of appropriate guidelines.
While several educational, regulatory or administrative measures can be adopted to correct the noted fallacies as described above, our endeavor in future would be to make some suitable interventions and to assess their impact on the quality of drug use in our hospital.
The pooled data of all the patients show that antibacterial agents are widely used in the admitted patients in all surgical units irrespective of whether an operative procedure was carried out or not. The extent of antibacterial drug use is in all the surgical specialities. Newer cephalosporins like cefotaxime have replaced penicillin in most of the conditions, along with metronidazole & gentamicin as broad spectrum cover. Multiple antibacterial drug use is very common. Irrational and inappropriate use of antibacterial agents for surgical prophylaxis has been observed in this study. This includes inappropriate choice of drug and duration of use in most of cases. No significant difference is observed as far as antimicrobial used. Inadequate and almost minimal use of microbiological support while prescribing antibacterial agents has been observed. These results indicate a considerable scope for improving the prescribing pattern of drugs and minimizing the use of antibacterial agents in all surgical specialties.
Education programs for prescribers on use of antibacterial agents, preparation of a restricted list of hospital formulary, appropriate selection and utilization of antibacterial susceptibility tests and automatic “stop” orders for specific high cost agents are some of the measures suggested in this direction. We propose to make some suitable interventions in future and to assess their impact on the utilization of antibacterial drugs in our hospital.