Prevalence of Urinary Tract Infection due to Urinary Catheterization in Obstetric and Gynaecological Operations

: Background : Urinary catheterization is routinely done in major gynaecological and obstetric operations in our country. It has some advantages and disadvantages of its own. Among the advantages, it can significantly prevent retention of urine, help in measuring urinary output, avoid discomfort due to full bladder, prevent postpartum hemorrhage and reduce spinal headache due to reduced movements. On the other hand, it can be a constant source of urethral irritation leading to UTI and can cause urethral strictures. So, a quantitative research is necessary to determine the relationship between urinary catheterization and UTI, for establishing a guideline for judicious catheterization. Methods: Between January 2010 and December 2011, data was collected for conducting an cross-sectional observational study on 49 subjects undergoing various gynaecological and obstetric operations. Precatheterization urine for routine and culture-sensitivity findings were recorded and compared with catheter tip culture and sensitivity after removal. Besides, other factors e.g. clinical history, comorbidity status, hemoglobin status, duration of catheterization, nature of operation etc was brought into consideration. Results : Patients having urinary catheters for more than 5 days, were found to be more than twice as likely to be developing UTI in various operations, than the patients having catheter for one day. Preoperative albuminuria was also found to be a likely predisposing factor, as the percentage of patients with UTI who had preoperative albuminuria was double compared to the preoperative albuminuria negative patients. The direct relationship between nature of operation and development of post-catheterization UTI was difficult to establish, because of the duration of catheterization acting as a confounding variable. Conclusion : In most cases of LUCS and hysterectomy, catheter-associated complications can be overcome by avoiding catheterization altogether. This can be better achieved by encouraging the patient to void their bladder immediately before surgery. In long and complicated operations, catheterization cannot be avoided but the postoperative duration of catheterization can be reduced to avoid complications. Moreover, preoperative optimization of comorbid status, hemoglobin status, albuminuria etc can bring forth a favourable outcome in terms of catheter-associated complications.


Introduction
Urinary tract infection in gynaecological and obstetric cases is a matter of morbidity, anxiety, long stay in hospital and of course the reason for more expenditure by the patients. 1 Undoubtedly surgeons feel embarrassed to get a post-operative infection. 2 Although this is an era of newer and more effective antibiotics, urinary tract infection still continues to be a very common complication. Catheter associated UTI comprises perhaps the largest reservoir of nosocomial antibiotic resistant pathogens. 3 This could lead to complications like pyelonephritis and bacteraemia.World Health Organization (WHO) in its manual reported that urinary tract infection stood at first position among nosocomial infections followed by pneumonia and surgical wound infection. 4 In a study at Dhaka Medical College Hospital (DMCH), Hussain et al found nosocomial infection in 38% of surgical patients of which over 23% was suffering from UTI. 5 The fact is that urinary infection which develops following catheterization is mostly due to faulty technique of paramedics. They touch the tip of catheter to surrounding area in search of opening of urethra and contaminate the catheter. Sometimes they do not use any type of antiseptic. This ultimately causes a negative correlation with operative success. Risk factors for acquiring infection would be of following categories as host factors, surgical factors, environmental factors and the nature of microbes. Host factors contributing to increased risk of infection are age, length of hospital stay and concurrent infection at other sites of the body. 3 Among surgical factors, the nature and extent of operation, logistics used during and after operation and even surgeon's own technical skills are remarkable. Among microbial factors virulence and numbers of bacteria are important. Local tissue defence can combat minute inoculum of avirulent bacteria. But if host damage is extensive and premorbidity in the form of diabetes or other immunosuppressive condition remains, small inoculum of avirulent bacteria can ensue an overwhelming infection. On the other hand, virulent bacteria of drug resistant nature may be the single factor for an overt and fulminant infection. 1,6,7 Materials and methods This cross sectional study was carried out at the Department of Gynaecology and Obstetrics, Medical College for Women and Hospital(MCWH), Uttara, Dhaka, and at one private clinic at Uttara, Dhaka. Duration of study was from January, 2010 to December, 2011. The patients undergoing Lower Uterine Caesarian Section (LUCS), Transabdominal Hysterectomy (TAH), Vaginal Hysterectomy (VH), Laparoscopy or Laparotomywithin the period were included in this study. Urine for routine microscopic examination and culture sensitivity were carried out preoperatively in all patients selected for this study. Those patients who had signs and symptoms of UTI before catheterization and those patients who had been found positive for pre-catheter urine culture, were excluded from the study. Peroperative catheterization was done under strict aseptic precautions. Duration of catheterization was between 24 hours to 10 days. Immediately after removal, the catheter tip was introduced into a sterile test tube and cut from the rest part of the catheter by a sterile scissor and sent to microbiology department. The urine from the catheter tip was studied for identification of bacteria by standard procedure. Initially, 53 patients with peroperative catheterization were selected for the study. But, later, the report of pre-catheter urine culture was found positive in 4 patients and were excluded from the study. So, finally 49 patients were included in this study. All relevant findings regarding history, comorbid status, investigations like haemoglobin status and urine for routine and culture examination, name of the operation and duration of catheterization were recorded in apreset data sheet.The data were analyzed by SPSS version 17 and presented in appropriate tables and figures as required.

Ethical Approval
The study was approved by Ethics Committee of Medical College for Women and Hospital (MCWH), Uttara, Dhaka.

Results
Total number of patients = 49 Age range = 16 -75 years Average = 32.53 years The graph shows age groups of patients included in the study. Among the different age groups 14 patients belong to the 26-30years age group. 10 of them are between 21 years to 25 years old. 2 patients are above 50 years old. The The table shows Hb% of the patients. 35 (71.43%) patients had Hb% within the range of 9 to 11.9 gm/dl. 2 (4.08%) patients had Hb% below 9gm/dl. This table shows distribution of patients according to Hb% and type of operation. Amongst 31 patients undergoing LUCS, 22 (70.97%) patients hadHb% within the range of 9.0-11.9 gm/dl, 7 (22.58%) had above 12gm/dl and 2 had below 9gm/dl. Amongst the 8 patients having TAH, 5 (62.5%) patients had Hb% within the range of 9.0-11.9 gm/dl, and 3 (37.5%) had above 12.0 gm/dl.  Among the 15 patients who developed UTI, 11 of them had growths of E. coli in the catheter-tip urine Culture. Acinetobacter was isolated from 3 of the patients, 1 of them simultaneously had a growth of Pseudomonas.

Discussion
Urinary tract infection is among the most common infections in human, which can occur in otherwise healthy individual or in compromised patients from newborn to the elderly. The urinary tract is normally sterile. UTI is commonly caused by bacteria from the patient's own intestinal flora, which enter the urinary tract via the urethra. The specimens should be cultured within 2 hours after collection or refrigerated until processed. 8,9 The following are some observations that came out from analysis of the data obtained from selected patients attending and operated at MCWH and one Private clinic. Here we have observed that among the 27 patients who had their catheters for 1 day, only 5 patients developed UTI. But, for the 4 patients having catheters for 5 days, half of them developed UTI. It can also be noted that, every patient, who had been catheterized for 7 days or more, had developed UTI. This is obviously owing to susceptibility of the urinary tract towards ascending infection by organisms for a prolonged period of time. This association between duration of catheter and UTI is supported bypreviously published literatures and suggests a mechanism through which postoperative morbidity and mortality is increased. 10 18 Microalbuminuria is an indicator of increased capillary leak resulting from endothelial damage that is observed asa consequence of the systemic inflammatory response 19 . This is in turn accompanied by a higher percentage of complication, especially respiratory distress and Multiple Organ Dysfunction.

Conclusion and Recommendation
Urethral catheterization has long been recognized to be the primary cause of bacteriuria and urinary infections. Mustafa and Pinkerton suggested that catheterization is usually unnecessary when the urethra is not surgically involved. 20 Authors have drawn attention to the high incidence of urinary tract infection in gynaecology, related to the use of postoperative catheterization, and antibiotic prophylaxis has been recommended. The complete avoidance of the use of a catheter, however has been shown to have a profound beneficial effect in reducing the urinary infection rate. Clearly, in some patients, particularly where the urethra and bladder neck are involved, it is not possible to avoid the use of a catheter. In most patients having a Caesarean section or hysterectomy, the most common complication can be virtually eliminated if catheterization is avoided. This can be better achieved if the patient is advised to empty her bladder as close to the operation starting time as possible. The catheter cannot be avoided in lengthy or complicated surgery. If catheterization is mandatory, we believe reducing the catheterized time to a minimum of 2 postoperative days result in best outcome. In addition, optimization of preoperative Hb%, urinary albumin etc. has a beneficial effect on the patients' outcome. The sample size of this study was small and we believe a large RCT based study in multiple centres needs to be conducted, to identify the risk factors and predictors of postoperative UTI in the catheterized patients.