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Background: The ability to estimate the mortality risk, especially in costing setting like ICU, is of great importance in order to evaluate new treatments, resource consumption control and improve quality control. Acute physiology and chronic health evaluation system (APACHE) is developed to predict critical care outcomes. In this system, according to the setting, a score is considered for each patients. Then using an equation, predicted mortality risk for each patients could be estimated.
Materials and methods: In a prospective study, we observed 269 ICU patients over a 10-month period. We calculated APACHE III scores for each patient and predicted mortality risk. Accuracy of the results were checked with regression analysis.
 Results: Totally, 51.7% of patients were female while the mean age was 61.2 years. APACHE III average score was 60.6. Predicted mortality risk was 25.6% while actual death rate was 27.1%, therefore, SMR (actual death rate to predicted mortality risk ratio) was 1.05.
Conclusion: Results revealed an association between actual death rate and APACHE III score and patient's age (P =0.0001), however, sex and death rate were not statistically correlated. The obtained SMR represents direct linear association between predicted and actual death rate (P=0.0001).

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Background: pseudomonas aeruginosa as an opportunistic pathogen is the most important infectious agent in hospital and has resistance to the common antibiotics. In this study, susceptibility of pseudomonas aeruginosa to quinolones and beta-lactams, and also relation of bacterial capsule and antibiotic resistance were assessed.
Material and methods: In this experimental study, 100 strains of pseudomonas aeruginosa from Imam Khomeini hospital were collected and its susceptibility to some of quinolones and beta lactams was determined on the basis of the minimum inhibitory concentration on agar. In order to detection mucoid and non-mucoid strain, capsule was detected by India- ink staining and alginate precipitation methods, and then relation of bacterial capsule and antibiotic resistance was evaluated.
Results: MIC method demonstrated 90% susceptibility to ofloxacin, 89% to ciprofloxacin, 59% to nalidixic acid, 43% to ceftizoxime and 39% to ceftriaxone. The susceptibility of these strains was also examined on the basis of disk diffusion agar on moler Hinton medium, and susceptibility to used antibiotics was as following: co-amoxiclave 0%, ceftizoxime 23%, ceftriaxone 29%, carbenicillin 48%, nalidixic acid 50%, Ticarecillin 53%, Ciprofloxacin 36%, ofloxacin 70% and norfloxacin 89%. All strains had alginate capsule and only diameter of capsules was different between strains.
Conclusion: This study showed that the method of disc diffusion has less accuracy compared to MIC in determining susceptibility to antibiotics.

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Background: To prevent the anesthesia circuit from bacterial colonization, during the time, we used to have an antibacterial filters with no predicted changing algorithm. In this study, we evaluated the effect of exchange time anesthetic circuit anti- bacterial filters, on microbial culture results of anesthetic circuits in Bouali Hospital operating theaters. Materials and methods: During a descriptive-analytic study, we changed the antibacterial filters in 4 different operating rooms; per patients at 1st room, daily at 2d room, 2times a week at 3rd room & weekly at the last one and kept them for the first week of study. At the rest of time until 10 months, we changed the filters in a manner to equal changing algorithm on all 4 rooms. we had microbial culture exam from the Y-piece & Mount-catheter every week ends. Results: Changing filter algorithm were 243 surgeries (25.5%) per patient (group1), 243 surgeries (25.5%) daily (group2), 237 surgeries (24.6%) twice a week (group3) and 241 surgeries (25%) weekly (group 4). The positive culture results were obtained on 21 operations (2.2%) in Y-piece and 27 operations (2.8%) in Mount-catheter. Conclusion: When we consider the whole number of surgeries in one day as a unit, positive culture results on Y-piece in each group would be 1(2.6%) for group1, 0 for group 2 , 2 (5%) for group 3, 1(2.5%) for group 4 (P=0.9). For Mount-catheter positive culture results were 2(5.1%) for group 1, 0 for group 2, 1(2.5%) for group 3 and 1(2.5%) for group 4 (P=0.6). No differences were found on concomitant positive culture tests from Y and Mount pieces. Keywords: Microbial culture, Anesthesia circuit, Anti-bacterial filter.

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Background: Listeriosis can be fatal for vulnerable groups of society. The disease has been widespread in recent years due to the large consumption of dairy and meat products. There is little information about the susceptibility of antibiotics and the pattern of Listeria monostigenesis gene resistance in Iranian society. Accordingly, the present study was conducted to investigate the antibiotic susceptibility and genetic resistance pattern of Listeria monosteogenesis strains isolated from different clinical and environmental sources.
Materials and methods: In this study, 55 isolates were tested for antibiotic susceptibility by disk diffusion in agar and genetic pattern by polymerase chain reaction (PCR).
Results: 91% and 83% of the strains were resistant to streptomycin and Trimethoprim/sulfamethoxazole respectively. The result of PCR of antibiotic resistance genes showed that the prevalence of ermA, ermB, strA, tetA, tetS and ermC genes in isolates of Listeria monocytogenes was 50.90% (28/55), 21.81% (12/55), 89.9% (49/55), 0% (0/55), 21.81% (12/55) and 0% (0/55), respectively.
Conclusion: Due to the presence of 1/2a and 1/2c serotypes in isolated isolates and the presence of marker virulence genes in these strains, these isolates have potential for biological risks and listeriosis disease. Existence of this genetic pattern and resistance pattern can be partly due to the use of antibiotics during the production of dairy products. Regarding results of this study, the manner and rate of using animal antibiotics can be managed.

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Background: One of the bitter experiences is acute postoperative pain. The severity of this pain has been reported as moderate to severe in 21% of patients.
Materials and methods: In this controlled randomized clinical trial, 106 consecutive patients under elective abdominal surgery in Bouali Hospital were enrolled and randomly assigned to receive alprazolam or placebo the night before surgery. The pain severity was determined by visual analog scale (VAS) and compared between the groups at three intervals, including recovery time, and 4 hours and 24 hours after surgery.
Results: The mean age (P=0.55) and gender (P=0.78) of patients were similar between the two groups. 24-hour analgesic dose (meperidine) was significantly lower in patients that received alprazolam (25±0 mg) compared to placebo group (35.53±12.68) (P=0.002). The pain severity in VAS was 7.70±1.84, 4.96±1.56 and 3.06±1.35 cm in alprazolam group, and 7.55±1.44, 5.70 ± 1.19 and 3.94 ± 1.13 cm in the placebo group, in recovery time, and 4 hours and 24 hours after surgery respectively.
The results in this study revealed that there was statistically significant difference at first 24 hours after surgery (P=0.038) but were no statistically significant differences between two groups for the postoperative pain in recovery and in first 4 hours (P > 0.05). Also
Conclusion: The results in this study revealed that there was statistically significant difference at the first 24 hours after surgery (P=0.038), but were no statistically significant differences between two groups for the postoperative pain in recovery and in first 4 hours (P>0.05). Also 24-hour analgesic dose (meperidine) was significantly lower in patients that received alprazolam (P=0.002).