the marketing , distribution , prescription and use of drugs in a society , with special emphasis on resulting medical , social and economic consequences is known as drug utilization research . it is an important tool to study the clinical use of drugs in populations and its impact on health - care system . the critical care unit ( ccu ) is a setting where the multiple medications are prescribed to patients . the costs of hospitalization and treatment are high in ccu as patients are seriously ill and often suffer from the chronic critical illnesses . ccu services use higher economic resources due to frequent use of high priced drugs and antimicrobial agents . due to availability of limited funds in developing countries , drugs should be prescribed rationally so that the available funds can be utilized optimally . the ccu is considered as the epicenter of antimicrobial resistance and it is an important problem influencing patient outcomes . incidence of poor treatment response and adverse reactions increase due to critical conditions of patients and use of multiple medications with altered pharmacokinetic and pharmacodynamic conditions . periodic evaluation of drug utilization in the ccu is necessary for optimization of health care system , proper use of resources and making prescription policy . the assumed average maintenance dose per day for a drug used for its main indication in adults is called defined daily dose ( ddd ) . use of ddd is an important tool to compare the drug utilization among different clinical setups within a country and between different countries . ddd/100 bed - days provide a rough estimate of drug consumption in hospital inpatients and it is a fixed unit of measurement independent of formulation and price . in the present study , we have evaluated the drug utilization pattern and calculated the ddd for the drugs used in ccu of a tertiary care hospital . a retrospective study was carried out , after the permission from institutional review board , government medical college , bhavnagar , gujarat , india . indoor case papers of the patients admitted in ccu between january 2008 and december 2010 were collected from the medical record section of sir takhtsinhji general hospital , bhavnagar , gujarat , india . data were collected for age , gender , diagnosis , duration of ccu stay , laboratory investigations and treatment provided during the stay in ccu . culture and sensitivity reports and adverse drug reaction if mentioned in case papers were also noted . data were analyzed for demographic variables ; indication of admission in ccu and systems involved ; duration of ccu stay ; total number of drugs prescribed per patient ; proportion of common group and particular drugs used ; the total number of antimicrobials and inotropes used per patient ; use of fixed dose combinations ( fdcs ) ; use of generic and brand drugs ; use of oral and parenteral formulations ; use of the five most costliest drugs ; organisms isolated and their antimicrobial sensitivity and outcome of the patient . total cost of drugs per patient was calculated from the indian drug review ( 2010 ) . total cost of laboratory investigations per patient was calculated according to the price list of bhavnagar pathologist association . the drugs were classified according to the anatomical therapeutic chemical classification based on their chemical , pharmacological and therapeutic properties . ddd/100 bed - days were calculated using the following equation : in our ccu , bed strength was 10 and average bed occupancy rate was 0.6 during the study period . data were expressed as proportions and mean ( 95% confidence interval [ ci ] ) . comparisons of the total number of drugs prescribed per patient ; duration of ccu stay ; and cost of total treatment , antimicrobials and inotropes per patient were performed using the kruskal - wallis test followed by dunn 's multiple comparison test between patients admitted with medical , surgical and medical + surgical indications . same parameters were compared between survived and expired patients using mann - whitney u - test . data were expressed as proportions and mean ( 95% confidence interval [ ci ] ) . comparisons of the total number of drugs prescribed per patient ; duration of ccu stay ; and cost of total treatment , antimicrobials and inotropes per patient were performed using the kruskal - wallis test followed by dunn 's multiple comparison test between patients admitted with medical , surgical and medical + surgical indications . same parameters were compared between survived and expired patients using mann - whitney u - test . 2 ( 0.5% ) patients were below 12 years ; 221 ( 55.67% ) patients were between 12 and 49 years and 174 ( 43.83% ) patients were above 49 years of age group . the mean age of admitted patients was 44.62 years ( 95% ci : 42.56 - 46.69 years ) . a total 246 ( 61.96% ) patients were male and 151 ( 38.04% ) were female . total 278 ( 70.03% ) , 71 ( 17.88% ) and 48 ( 12.09% ) patients were admitted with medical , surgical and medical + surgical indications respectively . the common indications for the admission were septicemia ( 35.37% ) , head injury ( 32.39% ) , complicated acute abdomen ( 25.35% ) , cardiovascular emergencies ( 21.94% ) and organophosphate poisoning ( 17.27% ) . total 170 ( 42.82% ) , 119 ( 29.97% ) and 108 ( 27.21% ) patients had one , two and more than two system involvement respectively . cardio vascular ( 37.28% ) was the most commonly involved system followed by gastro intestinal ( 36.52% ) , central nervous system ( 31.49% ) , respiratory ( 24.69% ) , renal ( 20.91% ) , hematology ( 17.63% ) , endocrine ( 8.82% ) and genitourinary ( 2.77% ) . the average duration of ccu stay was 4.15 days ( 95% ci : 3.79 - 4.51 days ) . a total of 5377 drugs ( 86.57% parenteral and 9.60% oral formulations ) were prescribed in all patients . the minimum and maximum number of drugs prescribed to a single patient was 2 and 28 , respectively . the average number of drugs prescribed per patient was 13.54 ( 95% ci : 13.05 - 14.04 ) . total drug utilization in ccu during the study period in terms of ddd/100 bed - days was 226.27 . metronidazole , cefotaxime , atropine , adrenaline , dopamine , dobutamine , etofylline + theophylline hydrate , ranitidine , metoclopramide and furosemide were prescribed in more than 30% of patients . ceftriaxone , ciprofloxacin , noradrenaline , hydrocortisone , aspirin and pantoprazole were used in 10 - 30% of patients . utilization pattern of various drugs and ddd/100 bed - days has been shown in table 1 . the commonly prescribed fdcs are described in table 2 . among all the prescribed drugs , 18.48% were antimicrobials and 11.94% were inotropes . the antimicrobials and inotropes were used in 375 ( 94.45% ) and 285 ( 71.79% ) patients respectively . the average number of antimicrobials prescribed per patient was 2.50 ( 95% ci : 2.37 - 2.66 ) . the average number of antimicrobials prescribed was significantly higher in expired than survived patients ( 2.80 [ 95% ci : 2.61 - 2.30 ] vs. 1.84 [ 95% ci : 1.7 - 2.06 ] ; p < 0.05 ) . the average number of inotropes prescribed per patient was 1.62 ( 95% ci : 1.49 - 1.75 ) . cefotaxime + metronidazole ( 26.70% ) , ceftriaxone + metronidazole ( 16.88% ) , cefotaxime + gentamicin ( 7.81% ) and ceftriaxone + gentamicin ( 3.78% ) were the commonly used empirical regimens . change in antibiotic was performed in 10 cases ( 58.82% ) based on isolated organisms and their sensitivity pattern . isolated organisms were klebsiella ( 40% ) , pseudomonas ( 20% ) , escherichia coli ( 10% ) , staphylococcus aureus ( 10% ) , candida ( 10% ) , proteus vulgaris ( 5% ) and acinobactum ( 5% ) . among 50% cases , s. aureus was sensitive to penicillin , oxacillin , cefazoline , ciprofloxacin , roxithromycin , tobramycin , amoxicillin + clavulanic acid , chloramphenicol and rifampicin . the sensitivity pattern of gram - negative organisms to various antimicrobials is shown in figure 1 . utilization pattern of various drugs in ccu , atc code and ddd/100 bed - days most commonly prescribed fdcs sensitivity pattern of gram - negative organisms to various antimicrobial drugs the average total cost of treatment per patient was rs . human - albumin , meropenem , methylprednisolone , piperacillin + tazobactum and enoxaparin sodium were the most costly drugs used in ccu . the total cost of treatment in medical + surgical indications was significantly higher than patients with medical and surgical indication alone ( p < 0.05 ) . the comparison of the total number of drugs administered per patient , duration of ccu stay , cost per patient for total drugs , antimicrobials and inotropes in medical , surgical and medical + surgical indications are shown in table 3 . the mortality rate for patients admitted with medical , surgical and medical + surgical indications were 71.58% , 52.11% and 79.17% , respectively . total number of drugs administered per patient , duration of ccu stay and total cost per patient for survived and expired patients are shown in table 4 . comparison of the total number of drugs , duration of ccu stay in days , total cost per patient , antimicrobials cost per patient and inotropes drugs cost per patient between patient admitted with medical , surgical and medical+surgical indications comparison of the total number of drugs , duration of ccu stay in days , total cost per patient , antimicrobials cost per patient and inotropes drugs cost per patient between survived and expired cases male preponderance ( 61.96% ) is observed and male : female is in accordance with the previous reports . patients were admitted for medical and surgical indications due to unavailability of separate intensive care units in our hospital . the most common indication for admission septicemia is in contrast to previous studies , which had reported cancer , cardiovascular emergencies and chronic obstructive pulmonary disease . head injury ( 32.39% ) , complicated cases of acute abdomen ( 25.35% ) and cardiovascular emergencies ( 21.94% ) were the other causes for admission in accordance with the previous studies . total 57.18% patients were having more than one illness , which is similar to other published report . the average duration of ccu stay ( 4.15 days ) is similar to shankar et al . use of brand names ( 45.77% ) and fdcs ( 7.21% ) are comparatively lower in our study . however , use of parenteral drugs ( 86.57% ) is higher than previous studies . the average total number of drugs prescribed per patient is higher than the reported in other studies . use of the total number of drugs and parenteral formulations may be related with the general condition of the admitted patients in different ccu settings . antimicrobial drugs ( 94.45% ) , antipeptic ulcer drugs ( 89.67% ) and inotropes ( 71.79% ) were the commonly utilized groups similar to john et al atropine was used in patients of organophosphate poisoning , as a premedication and for bradycardia in late stages of septic shock . in critical care setting , it does not prevent all episodes of bradycardia and vasodilation when used before intubation . use of atropine is appropriate to counter bradycardia , cardiac hypo - oxygenation and hypoperfusion in septic shock . dopamine , dobutamine and noradrenaline were used in combination with intravenous fluids for the patients of septic and cardiogenic shock . inotropes are mainly effective in early stages of shock . their late application for a prolonged period may harm the patient . there is no significant difference in mortality in patients of shock treated with dopamine and noradrenaline . cephalosporins ( 73.30% ) , metronidazole ( 55.67% ) and penicillins were the most commonly prescribed antimicrobials similar to previous studies . however , aminoglycosides , meropenom , fluoroquinolones and piperacillin + tazobactum were the most utilized antimicrobials in other setup . in our study , linezolid , meropenam , vancomycin , netilmycin and tobramycin were used as second line antimicrobials . other studies had reported pseudomonas , e. coli and s. aureus . our study showed lower utilization of antibiotic sensitivity testing than shalini et al . it is difficult to suggest the empirical antimicrobials for admitted patients due to underutilization of antibiotic sensitivity testing . the antimicrobial combination form the different classes should be considered for the septicemia due to high mortality . the empirical combination antibiotic regimen directed against gram - negative bacteria ( carbapenem plus aminoglycoside or fluoroquinolone ) reduces the initial inappropriate selection as compared to monotherapy alone . amoniglycosides offer broader coverage than fluoroquinolones as combination agents for patients with this serious infection . the combination of carbapenems and aminoglycosides can be preferred in patients with severe sepsis and septic shock . there is an urgent need to enhance the utilization of antibiotic sensitivity testing for the better selection of antimicrobials and reduction of the mortality . avoiding the use of unnecessary antibiotics helps to improve patient outcomes . in the present study preparation of antibiotic use policy helps in reduction in nosocomial infections and have a positive impact in the form of costs reductions . the average cost of treatment prescribed per patient [ rs . 3225.7 ( $ 57.74 ) ] is higher in comparison with two studies by shankar et al . in nepal . however , cost of treatment was lower than the biswal et al . from india and inan et al . from turkey . difference in the mean cost of treatment in our study than other studies may be due to variation in type and severity of the admitted patient , indications for the admission , different prescribing pattern or change in currency differences of various countries . this is due to the higher number of drugs used and duration of ccu stay . this may be because of a higher number of patients with septicemia , head injury , poisoning and unavailability of the separate intensive care units for medical and surgical patients . being a retrospective nature it was not possible to assess the rationality and quality of prescriptions . however , it helps to create drug utilization database in a tertiary care teaching hospital of developing country lacking separate medical and surgical intensive care units . these data provides no direct link with the outcomes associated with the use of the various categories of drugs . line of treatment and selection of drugs varied by the physician - to - physician and it provide no data for the same . prescribing guideline is required to reduce the prevalent poly - pharmacy and to promote appropriate use of antimicrobial drugs based on the culture and sensitivity report .
aims : the aim of this study is to evaluate the drug utilization pattern and pharmacoeconomic analysis in critical care unit ( ccu).materials and methods : indoor case papers of patients admitted in ccu between january 2008 and december 2010 were analyzed for demographic variables ; indications ; duration of ccu stay ; proportion of common drugs used . 
 use of antimicrobials was evaluated based on the culture report and empirical regimen used . 
 defined daily dose ( ddd)/100 bed - days were calculated . 
 various world health organization prescribing indicators were evaluated . 
 cost of drugs was calculated from indian drug review ( 2010).results : a total of 397 cases were evaluated with a mean age of 44.62 years ( 95% confidence interval [ ci ] : 42.56 - 46.69 ) . 
 average duration of ccu stay was 4.15 days ( 95% ci : 3.79 - 4.51 ) . 
 the average number of drugs prescribed per patient was 13.54 ( 95% ci : 13.05 - 14.04 ) . total drug utilization in terms of ddd/100 bed - days was 226.27 . 
 metronidazole , cefotaxime , atropine , adrenaline , dopamine , dobutamine , deriphyllin , ranitidine , metoclopramide and furosemide were prescribed in more than 30% cases . 
 number of antimicrobials prescribed per patient was 2.50 ( 95% ci : 2.37 - 2.66 ) . cefotaxime + metronidazole ( 26.70% ) were the most common empirical regimen used . 
 average cost of treatment per patient was rs 3225.70 ( 95% ci : 2749.8 - 3701.6 ) . 
 higher economic burden was noted among expired patients and admitted due to medical + surgical indication ( p < 0.05).conclusion : poly - pharmacy and use of antimicrobials without culture report is a common problem in ccu .