Some related factors to nosocomial infection in the intensive care unit of national hospital for tropical diseases – Doan Quang Ha

Journal of military pharmaco-medicine n o 9-2018 185 SOME RELATED FACTORS TO NOSOCOMIAL INFECTION IN THE INTENSIVE CARE UNIT OF NATIONAL HOSPITAL FOR TROPICAL DISEASES Doan Quang Ha1; Nguyen Van Kinh1 Nguyen Vu Trung1; Nguyen Van Chuyen2 SUMMARY Objectives: To describe some of factors related to nosocomial infection in Intensive Care Unit of National Hospital for Tropical Diseases (2011 - 2012). Subjects and methods: A prospective study evaluating some of factors related to nosocomial infection in Intensive Care Unit from Jan 2011 to Dec 2012 on 682 inpatients. Results: Invasive interventions were associated with nosocomial infection, including: gastrostomy, mechanical ventilation, central venous catheterization, angioplasty and catheterization. There is a relation between duration of therapy and the risk of nosocomial infection. Patients hospitalized for 10 - 15 days had the highest risk of hospital- acquired infection. Risk factors for hospital pneumonia: Intubation for more than 5 days; risk factors for hospital sepsis: central venous catheterization more than 3 days; risk factors for urinary tract infection: urinary catheter more than 3 days. Conclusions: Medical invasive interventions and duration of therapy are the main factors influencing nosocomial infection in the Intensive Care Unit of National Hospital for Tropical Diseases. * Keywords: Nosocomial infection; Related factors. INTRODUCTION Nosocomial infections (NI) is a bacterial infection that patients suffer during hospitalization, which is one of the main causes of morbidity and mortality for patients in hospitals around the world [2]. NI is usually caused by antibiotic-resistant bacteria, which makes it difficult to treat, prolong hospital stay, increase the risk of death and the cost of treatment. In the European Union, the annual mortality rate from infections with resistant strains is 25,000 and in the United States over 63,000. According to a survey conducted by the WHO in 55 hospitals in 14 countries, the average NI rate was 8.7% wheres West Mediterranean: 11.8%; Southeast Asia: 10.0%; Europe: 7.7% and Western Pacific 9.0%, among of which pneumonia accounts for the highest rate, followed by septicemia, surgical site infections and urinary tract infections. These infections account for 80% of all cases of NI and causes huge economic losses including increased cost of treatment and reduced labor. Each year, it costs of the US 5.7 billion for patient care, much higher than the cost of influenza prevention [3]. 1. National Hospital for Tropical Diseases 2. Vietnam Military Medical University Corresponding author: Doan Quang Ha (ha_doan@nhtd.vn) Date received: 10/10/2018 Date accepted: 30/11/2018 Journal of military pharmaco-medicine n o 9-2018 186 Nosocomial infection at intensive care unit (ICU) is twice or 3 times higher than other departments in the hospital [4]. In Vietnam, there is no research on NI in ICU wards of NI, yet adequate analysis of risk factors related to NI has been made to provide appropriate intervention. This study aims: To describe some of the risk factors associated with NI in the ICU of the National Hospital for Tropical Diseases (2011 - 2012), as a scientific basis for interventions. SUBJECTS AND METHODS 1. Subjects, location, time. * Subjects: Patients who were treated in ICU of National Hospital for Tropical Diseases from 01 - 1 - 2011 to 31 - 12 - 2012. * Location: ICU of National Hospital for Tropical Diseases. * Time: January 1st 2011 - December 31st 2012. 2. Methods. * Research design: A prospective, case-control analysis of relacted factors of NI in ICU, the National Hospital for Tropical Diseases. * Sample size and sampling method: - Sample size: Total sample size of patients with NI in ICU who had treatment in period from January 1, 2011 to December 31, 2012. - Sampling method: Select randomly, continuous pattern. All patients eligible for ICU admission will be selected. - Inclusion criteria: Patients were treated in the ICU at least than 48 hours. - Exclusion criteria: Patients who had NI before admission to the ICU or have manifestations of NI within the first 48 hours since admission to the ICU. * Research variables and methods of data collection: - Research variables: + Major variables: Case definition: The NI standard is based on the WHO 2002 standard [1]. Time is calculated from 48 hours after entering Emergency-Intensive Care Department to 48 hours after leaving Emergency- Intensive Care Department. . Secondary variables: . Duration of treatment at ICU: from hospitalization to the discharge of Emergency- Intensive Care Department. . The entire duration of treatment: the time patient were treated in hospital. - Independent variables: + Invasive intervention: Intubation & mechanical ventilation, nasal continuous positive airway pressure, peripheral venous catheterization, central venous catheterization, urinary catheterization, Journal of military pharmaco-medicine n o 9-2018 187 gastroenteric tube feeding. Other interventions: drainage of pleural cavity, peritoneal cavity, aerosol, hemodialysis . Drug treatment: Antibiotics: When antibiotics are used, there is evidence of bacterial infection in patients. Other drugs: Corticosteroids, H2 blockers, vasopressors and inotropes (dopamine and dobutamine), macromolecules, muscle relaxants (diazepam and phenobarbital) are included when administered to patients for a minimum of 24 hours. . Blood transfusion: When a patient receives blood transfusions and blood products. . Parenteral nutrition: When the patient is fed with a solution containing protein or fat for at least 24 hours. . Time to place the instruments, or use the drug before NI: From the time of intervention until the detection of NI. If the patient does not have NI, it will be calculated from the time of placing or using the drug until the end of the intervention or when leaving the ICU. * Data collection: - Initial evaluation of the patient: Patients eligible for the study were examined, performed diagnostic tests and assessed their status, recorded gender, age, comorbidity, if any, date of entry. The initial information will be filled in the form. - Patient monitoring and evaluation: All patients were taken care, monitored and treated according to the hospital regimen in accordance with the condition and under the same control conditions of the NI. Patient interventions and treatments were documented on the date and time of use. Monitor and evaluate the NI related signs of each position. - Urinary catheterization: Test urine every 72 hours until urinary catheters were removed, when there is urine nitrite (+) and/or white blood cell (+), it was suspected of urinary tract infection. - Endotracheal intubation: When there is clinical febrile or changes in sputum or crackles lung sound, chest X-ray is indicated. - Intravenous catheter insertion: When there is a change in the injection site right away, or manifestation of the infectious disease syndrome, carry out tests to identify infections. - Tests to identify cases: Blood culture is done when the patient shows signs of infection: + There are 2 of the following 4 criteria: fever > 38.50C; rapid pulse; rapid breathing; neutropenia increases or decreases with age or rate neutrophil > 10%. + Evidence of infection or suspected by examination, test. Blood is collected from peripheral blood at a volume of 1 - 2 mL with sterile syringe, inserted into blood culture bottle BactecPeds plus/F and cultured with automatic BACTEC 9420. - Get a chest X-ray, obtain sputum by nasotracheal aspiration method (NTA) or use the endotracheal tube if the patient is Journal of military pharmaco-medicine n o 9-2018 188 intubated, when the patient have such symptoms as: cough, increased sputum, purulent sputum, hear crackles lung sound. Sputum suction device is a specialized sterile one designed specifically for the nose and trachea or suctioned through the endotracheal tube. Evaluate the quality of the specimen based on the Bartlett standard. - Urine culture was performed on the 3rd day after urinary catheterization and repeated when having symptoms: Dysuria, urinary retention, pain in pubic bone, or cloudy urine; if urinary catheters were not available, urine culture should be performed when there are symptoms: dysuria, urinary retention, pain in pubic bone, or leucocyte ornitrite in the urinalysis. Urine was obtained from a sterile syringe from the collecting tube of the urine vesicle if the urinary catheter was placed. A specimen was considered positive when there is at least 105 CFU/mm3. - Culture pus from wounds and secretions from drainage pipes to find pathogens. Pus, fluid, and wound secretions are removed by using sterile syringes or sterile sticks and then placed in sterile vials and sent to the laboratory. The specimens are then cultured to find the bacteria on aerobic and fungal environments if suspected of fungus. Interpretation of results: If an agent is isolated, it wil be considered as the cause of the disease. In the case of specimens cultured from two or more agents, the dominant agent will be considerd as the cause of the infection. In cases where the results are negative but there are still doubts, they might be cultured again. - Case definition and questionnaire completion: Patients were monitored for 48 hours after leaving the ICU, if there were NI symptoms during this period, it was also referred to as NI in the ICU. Case definition was in accordance with the WHO 2002 standard. The patient's final result was evaluated until discharge, total time in the ICU, the length of hospital stay and the cost of treatment were recorded. Complete the questionnaire when the patient left the ICU within 48 hours. Check the questionnaire, compared with the medical record when discharged. * Data analysis: Data were processed statistically by SPSS 22.0 software. Comparison and correlation: Comparing the exposure factors in two groups with NI and non-NI: Using t-test when comparing two means, test χ2 compares two ratios and Fisher's test compares two ratios have small samples; considered significance with p < 0.05 for two-sided. Determination of risk factors: Risk factors were analyzed by logistic regression. Significant risk factors in logistic regression analysis will have a corresponding regression coefficient β. Journal of military pharmaco-medicine n o 9-2018 189 RESULTS 1. Distribution of NI. Table 1: Relationship between invasive intervention and the NI. Non-NI (n = 383) NI (n = 299) Invasive intervention n % n % p-values Gastric sonde 159 41.5 146 48.8 0.057 Endotracheal intubation or ventilation 45 11.8 158 52.8 < 0.001 Central venous catheterization 12 3.1 121 40.47 < 0.001 Intravenous exposures 0 0.0 75 25.1 < 0.001 Angioplasty catheterization 6 1.6 60 20.1 < 0.001 Urinary catheter 107 28.9 105 35.1 0.015 Pleural effusion 53 13.8 32 10.7 0.219 Peritoneal drainage 31 8.1 14 4.7 0.075 Intravenous transfusion 01 line intravenous transfusion 02 lines intravenous transfusion 03 lines intravenous transfusion 174 170 39 45.4 44.4 10.2 134 134 31 44.8 44.8 10.4 0.987 Intravenous invasive interventions were associated with the NI, including gastric ulcer, endotracheal intubation - ventilation, central venous catheterization, intravenous exposures, angioplasty and urinary catheter. Table 2: Comparison of instrumental use index between the two groups with NI and non-NI by type of invasive intervention. Non-NI (n = 383) NI (n = 299) Invasive intervention Time (n = 2,843) IUI Time (n = 3,384) IUI p Gastric sonde 651 0.229 1.412 0.364 < 0.001 Endotracheal intubation 232 0.082 1.836 0.473 < 0.001 Central venous catheterization 49 0.017 1.187 0.306 < 0.001 Intravenous exposures 0 - 212 0.055 < 0.001 Angioplasty catheterization 15 0.005 171 0.044 < 0.001 Journal of military pharmaco-medicine n o 9-2018 190 Urinary sonde 350 0.123 299 0.091 < 0.001 Pleural effusion 115 0.04 103 0.027 0.004 Peritoneal drainage 70 0.025 45 0.012 < 0.001 Average 185,3 0.065 664.8 0.171 < 0.001 (Indicators use interventions [IUI)] = Instrument insertion time [INT]/total time of therapy) Figure 1: Correlation between instrument insertion time and IUI in group of NI. 0.229 0.082 0.017 0 0.005 0.123 0.04 0.025 0 100 200 300 400 500 600 700 G as tr ic s on de En do tr ac he al In tu ba tio n Ce nt ra l v en ou s ca th et er i.. . In tr av en ou s ex po su re s An gi op la st yc at he te riz at io n U rin ar y so nd e Pl eu ra l e ffu si on Pe rit on ea l d ra in ag e I n st ru m e n t in se rt io n t im e ( D a y s) 0 0.05 0.1 0.15 0.2 0.25 IUI INT Figure 2: Correlation between instrument insertion time and IUI in group of non-NI. The mean of IUI in NI patients was higher than in non-NI patients (p < 0.001). The results of figures 1 and 2 showed that there was a correlation between instrument insertion time and IUI. Long instrument placement increases the IUI, also increases the risk of NI. Journal of military pharmaco-medicine n o 9-2018 191 0 20 40 60 80 0 5 10 15 20 25 Hospitall ized time (days) P a ti e n ts i n t h e I C U No-HNI HNI Figure 3: Correlation between the number of NI cases and the number of days treated at the ICU. The number of NI cases increased gradually in the treatment group after 5 days. The number of NI was the highest in patients with 10 - 15 days. 2. The results of analysis of some risk factors related to NI. Table 3: Relationship between some risk factors of hospital pneumonia. Hospital pneumonia Invasie intervention Total Yes n = 135 Non n = 547 OR (95%CI) p Endotracheal intubation 203 (29.8) 68 (33.5) 135 (66.5) 3.0 (2.5 - 3.6) 0.001 Endotracheal intubation > 5 days 181 (26.5) 46 (25.4) 135 (74.6) 3,9 (3.1 - 5.1) 0.001 Block H2 216 (31.7) 49 (22.7) 167 (77.3) 1.3 (0.9 - 1.9) 0.215 Gastric sonde 305 (44.7) 65 (21.3) 240 (78.7) 1.2 (0.8 - 1.7) 0.386 Sedative 198 (29.0) 45 (22.7) 153 (77.3) 1.3 (0.9 - 1.9) 0.244 Muscle relaxant 107 (15.7) 26 (24.3) 81 (75.7) 1,4 (0.8 - 2.2) 0.234 Multivariate analysis revealed that the risk factors for hospital pneumonia were intubation with OR 3.0 (2.5 - 3.6), duration of intubation with OR 3.9 (3.1 - 5.1). The use of sedative, H2 blockers, peptic ulcer and muscle relaxant was not a risk factor for multivariate analysis (p > 0.05). Journal of military pharmaco-medicine n o 9-2018 192 Table 4: Multivariate analysis of risk factors for sepsis. Sepsis Invasive intervention Total Yes, n = 75 (%) No, n = 607 (%) OR (95%CI) p Central venous catheterization 133 (19.5) 75 (56.4) 58 (43.6) 2.3 (1.9 - 2.8) 0.001 Central venous catheterization > 3 days 132 (19.4) 75 (56.8) 57 (43.2) 2,3 (1.9 - 2.8) 0.001 No of intravenous transfusion ≥ 3 days 70 (10.3) 12 (17.1) 58 (82.9) 1.8 (0.9 - 3.5) 0.104 Intravenous exposures 75 (11.0) 75 (100) 0 (0) 0.001 Intravenous nutrition 155 (22.7) 17 (11.0) 138 (89.0) 1.0 (0.6 - 1.8) 1.00 Blood transfusion 217 (31.8) 26 (12.0) 191 (88.0) 1,2 (0.7 - 1.9) 0.600 By multivariate analysis, the risk factors for sepsis were placement of central venous catheterization with OR 2.3 (1.9 - 2.8); keep venous catheterization more 3 days with OR 2.3 (1.9 - 2.8); 100% of all cases of intravenous exposures were related to sepsis, transfusion 3 days, intravenous nutrition, blood transfusion was not a risk factor (p > 0.05). Table 5: Single-variable analysis of risk factors for urinary tract infections. Urinary tract infections Invasive intervention Yes, n = 16 (%) No, n = 666 (%) OR (95%CI) p Urinary catheter 16 (7.5) 196 (92.5) 1.08 (1.04 - 1.12) 0.001 Keep urinary catheter > 3 days 16 (7.5) 196 (92.5) 1.08 (1.04 - 1.12) 0.001 Single-variable analysis revealed that risk factors for urinary tract infections were urinary sonde OR = 1.08 (1.04 - 1.12) and time to urinary sonde > 3 days, OR 1.08 (1.04 - 1.12). Table 6: Multivariate analysis of risk factors for infection of intravenous transfusion site. Infection of intravenous transfusion site Invasive interventions Yes, n = 63 (%) No, n = 619 (%) OR (95%CI) p Central venous catheterization (b) 36 (26.3) 97 (73.7) 7.2 (4.2 - 12.4) 0.001 Number of intravenous transfusion sites (a) ≥ 2 33 (8.8) 341 (91.2) 0,9 (0.5 - 1.5) 0.692 Blood circulation drugs 13 (7.8) 153 (92.2) 0,8 (0.4 - 1.5) 0.540 (a: Venous; b: Central venous) Risk factors of infection for venous catheterization sites were central venous catheterization with OR 7.2 (4.2 - 12.4). Intravenous and blood circulation drugs were not risk factors for infection of catheterization sites. Journal of military pharmaco-medicine n o 9-2018 193 DISCUSSION Nosocominal infections in ICU are often the highest in most hospitals [3]. This situation is explained by the fact that in the ICU area more and more patients are at high risk of developing high levels of NI, such as severe disease, requiring multiple invasive procedures. Therefore, prevention of the NI is very important in ICU ward. For effective prevention, it is important to identify risk factors, on the basis of which measures to prevent and control NI well suited. Multivariate analysis results of each type of NI indicate that the risk factor for pneumonia is intubation with endotracheal time more than 5 days; the risk factor for hospital sepsis is intravenous central venous catheterization, maintenance of intravenous central venous catheterization more than 3 days and intravenous exposure; the risk factors for urinary tract infection are urinary catheterization and urinary retention time more than 3 days. Some domestic and foreign authors’ findings: Nguyen Viet Hung et al (2012) reported a relationship between NI and urinary done (OR = 3.5, p < 0.01), respiratory ventilation (OR = 2.9, p < 0.05) [4]. This result was consistent with the results from the US hospital surveillance statistics of 83% of bacterial pneumonia associated with artificial ventilation, 97% of urinary tract infections occured in patients with urinary catheterization and 87% sepsis occurred in patients receiving central venous catheters [4]. At the ICU of National Hospital for Tropical Diseases, most patients suffer from serious diseases and have undergone many invasive procedures such as respiratory ventilation, intravenous central venous catheter, urethral catheter... These results show that there needs to focus resources facilities on control of NI in the ICU area of the hospital, particularly the need for increased sterilization practice in the care of patients with invasive interventions involving the airway, blood vessels and urinary tract. CONCLUSSION Invasive interventions were associated with NI including intubation, respiratory ventilation, central venous catheterization, arterial catheterization and urinary sonde. There was a correlation between the duration of treatment and the risk of NI. Patients hospitalized for 10 - 15 days have a higher risk of NI. Risk factors for hospital pneumonia was endotracheal intubation more than 5 days; the risk factors for hospital sepsis were central venous catheterization for 3 days and intravenous exposures; the risk factor for urinary tract infection was the duration of the urinary catheter more than 3 days. REFERENCES 1. Nguyen Viet Hung et al. Rate of related factors and hospital infectious agents in Bachmai Hospital. Journal of Practic Medicine. 2012, 869 (5). 2. Ministry of Health. Guidelines for Hospital Infection Control. Medical Publishing House. 2013. 3. World Health Organization. Report on burden of endemic health care - associated infection worldwide. 2011. 4. World Health Organization. Prevention of hospital - acquired infections. Practical Guide. WHO Press. 2002.