Analysis Of Risk Factors Of Surgical Site Infections After Rectal Cancer Resection

Infection of incisional wound, which is also called surgical site infection( SSI for short), is one of the most common infections among surgical patients in hospitals. It is considered to be the third reason causing hospital infections, following the infections of urinary system and pneumonia. And proximally 14% to 38% infections could due to SSI in hospital. SSI can cause incision lately healing, disruption of wound, incisional hernia, and even generalized infection, resulting septicaemia, of which prognosis may be worse.While having many factors related to, it is considered that the main reasons are as follows:①some physiologic factors such as age, fat, malnutrition, being addicted to drink, etc, and some physiologic factors , like wound pollution, shock, blood transfusion, hypo-temperature, hyoxemia, nutrition disorder, cirrhosis, comorbidities, immunologic deficiency disease, endocrine system diseases(especially diabetes) and so on;②the type of the incision, operative sites, operation classification, operation time, and emergency operation;③electrotome using during an operation;④ an ostomy done in an colorectal operation.Nutrition disorder and immunodeficiency often occur in malignant tumor pationts, which could increase the risk of the SSI. Furthermore, the incisions of the rectal operations are the Class two wound, having the potential danger to undergoing SSI.Materials and methods: 452 patients who were made a rectal operation on were been chosen from Jan in 2005 to Dec in 2007 in the first hospital of Jilin university. 35 patients suffered SSI, comparing 19 males with 16 females. And there were 7 patients below 40 years old, 12 patients between 40 to 60 years old, and 16 older than 60, all of whose average age was 62.33. The criteria used to diagnose SSI are like these①The areas around the wound are changing to be red, swelling, hot, and painful, even there are some purulent secretion.②The drainage or paracentesis from deep incision contain liquor puris.③There are some liquor puris in automatic wound disruptions, or in the incisions opened by doctors. Or the patient's temperature is above 38℃, or there is some local pain.④Infection evidence is found in reoperations, or histopathology results, or anything like these.⑤Besides clinical diagnosis, there are also some evidence from etiology, such as positive secretion culture. The criteria of accumulating the quantity of smoking:①non-smoking: total quantity of smoking cigarettes is less than 100, or less than 1 per day. It makes sure that the members in this group have given up the habit of smoking for more than 6 months before joining this research.②Mild smoking: less than 10 packages per year(1 package = 20 cigarettes).③Medium smoking: 10 to 20 packages per year.④Serious smoking: more than 20 packages per year.Observation items:1. General data: the age, gender, and the amount of smoking cigarettes in postcolorectaloperation patients who are suffering SSI. Analyze the difference of gender, high risk of age, the relationship between smoking and SSI.2. BMI(Body Mass Index).3. Whether to have got a diabetes preoperation.4. Clinical manifestation.5. The type and the site of incision.6. Whether to detain a drainage tube in prevesical space. 7. The culture result of wound effusion, which is been done by the department of inspection in the first hospital of Jilin university. Statistics methodIt is been used to describe the experimental data that general average±standard deviation, frequency, percentage. X2 analysis has been used to value the qualitational analysis of data. It has statistical significance when P<0.05, meanwhile having predominant statistical significance when P<0.01.Results:1. 35 patients had got SSI in 362 postoperation patients, with the incidence of SSI being 7.7%, in whom there were 19 males(54.3%), 16 females(45.7%), as a result, the male female ratio is 19:16. Their average age is 62.33, which fluctuated from 32 to 78. the high risk age of SSI in males is above 60, meanwhile, so as females.2. The relationship between SSI and smoking: in this research, there are 129 patients non-smoking, in whom there are 5 suffer SSI; there are 98 patients mild smoking, in whom there are 6 suffer SSI; there are 100 persons medium smoking, in whom 7 suffered SSI; there are 35 people heavily smoking, in whom 17 had got SSI. In the 35 patients of SSI, there are 17 heavy smokers(13.6%), 7 medium smokers(20.0%), 6 mild smokers(17.1%),and 5 non-smokers(14.3%).3. Diabetes and SSI: in this research there are 24 persons diagnosed firmly diabetes, in whom 5 patients suffered SSI(20.8%); there are 398 people without diabetes, in whom there are 30 of SSI(7.0%).4. BMI: in this research, there are 7 patients of SSI in 95 less weight patients(7.4%); there are 13 of SSI in 241 patients with normal weight; there are 9 of SSI in 83 over-weighted patients(10.8%); in 33 fat patients, it occurred that 6 had got SSI(18.2%).5. The bacteria culture results of effusion: The number of the positive results is 32, in which Bacterium coli is 23, Pseudomonas aeruginosa is 5, Bacillus meningitidis purulentae is 3, and Staphylococcus aureus is 1. above all, the proportion of Bacterium coli is predominant.6. Clinic manifestations: The main clinical situation is red, swelling, hot, and high skin temperature around the wound, what is furthermore, there is some effusion. There are obviously painful in 97.1% patients, and skin temperature elevation in 94.3% patients.7. Different shapes of incisions: 452 patients applied longitudinal incisions, in whom 6 persons had got SSI(the infection rate is 9.9%); 290 people applied transverse incision, in whom 19 SSI happened(the infection rate is 6.6%).8. There are 132 patients in 452 having detained prevesical space drainage tubes, in whom 3 patients suffered SSI; the rest of 452 are without prevesical space drainage tubes, in whom 32 SSI occurred.Conclusions:1. There are no difference between gender, but there is a high incidence among older men.2. smoking can elevate the risk of SSI; it is the high risk factors of SSI that having got diabetes, over-weight, fat.3. It can preventing the SSI happening effectively that detaining prevesical space drainage tube.