Surgical site infection and associated factors among adult patients admitted in Bale Zone , Gindhir and Bale Robe General Hospitals , Oromia region , Southeast Ethiopia , 2020


 Background
 Surgical site infection is among the most preventable healthcare-associated infections. The magnitude and associated factors of surgical site infection in was not well documented in the study area. So the aim of this study is to assess surgical site infection and associated factors among adult patients admitted in Bale zone general hospitals, Oromia Region, Southeast Ethiopia, 2020.
Methods
 Hospital based cross-sectional study was conducted among all postoperative adult patients (260) who underwent surgery from March 1 to April 30/2020 in selected hospitals by simple random sampling. Pretested and structured questionnaires and observational checklists were used for data collection. Data were checked daily for completeness and entered to Epi data version 3.1 and analyzed by SPSS version 20. Frequency, percentage, mean and chart were used to present the result. Bi-variable and multivariable logistic regression analysis was implemented and those variables with a p-value of < 0.25 in bi-variable were a candidate for multiple logistic regression. P-value < 0.05 was considered as significantly associated with outcome variables.
Results
 A total of 260 patients participated in the study which gives a response rate of 90%. Of study participants, 139 (53.5%) were males and more than two-thirds of the respondents were from rural 174 (66.9%). The mean ages of the patients were 40.2, standard deviation ± 14.20 years. The prevalence of surgical site infection was 9.2%( 95% CI [5.7–12.7]). Patients with comorbidity disease AOR, 15.75(95% CI [2.81–33.42]), antimicrobial prophylaxis before operation AOR = 0.19(95% CI [0.06–0.53]) and body mass index ≥ 25 AOR, 12.5(95% CI [3-65.4]) where associated factors of surgical site infections.
Conclusion
 The magnitude of surgical site infections was comparatively high. Comorbidity disease, antimicrobial prophylaxis and body mass index ≥ 25 were associated factors. Efforts should be made to improve the appropriate and timely delivery of intravenous antimicrobial prophylaxis before surgery and health care providers should screen and manage co-morbidities.


Introduction
Surgical site infection (SSI) is an infection that occurs within 30 days after the operation or up to 1 year of implant use. Involves the skin and subcutaneous tissue of the incision (super cial incision) and the deep soft tissue (fascia, muscle) of the incision (1). Surgery is an essential component in health care, infections and complications after surgery and accounts for patient morbidity and mortality. Surgical site infections (SSIs) are those infections that are con ned to the incisions and involve structures adjacent to the wounds that were exposed during operation (2).
Surgical site infection has become a pay-for-performance metric and a target of quality improvement efforts (3). Surgical site infection is one of the most preventable health-care-associated infections, as well as a substantial burden to healthcare systems worldwide in terms of patient morbidity, mortality, prolonged hospital stay, prolonged therapy and additional costs (4). Surgical site infections (SSI) are public health problems even in developed countries and the second most common hospital-acquired infections in the world that account for 16% of nosocomial infections (5). Surgical site infection also causes prolonged hospitalization from 1.5 to 16.6 days and the estimated average cost of each surgical site infection in the United States of America is $2,739 (3). The overall incidence of surgical site infection in Brazil was 3.4% (5). In low and middle-income countries surgical site infection is the most frequent type of healthcare-associated infection and approximately one in 10 people who have surgery acquire surgical site infection and in Africa, the cumulative incidence of Surgical site infection high from and up to 20% of major surgery procedures lead to wound infection (1).
In Ethiopia, the magnitude of surgical site infection is still high and ranges from 5% (1) to 25.5% (7). The complications and burden of surgical site infection in terms of patient morbidity cost of treatment and mortality rate are still critical public health problems in Ethiopia.
Surgical site infection (SSI) accounts for 15% of all nosocomial infections and represents the most common nosocomial infection. The postsurgical infection leads to increased length of postoperative hospital stay, drastically escalated expense higher rates of hospital readmission, and jeopardized health outcomes (1).
Globally, surgical site infections among all surgeries were 23% annually with the worst complications causing prolonged hospital stays, increased resistance of microorganisms to antimicrobials, higher health system costs, emotional stress for patients and their families, and substantial economic burdens on hospitals (8). SSI rates range from 2.5-41.9% and are the third most frequently cause of nosocomial infection, and account for 14-16% of all nosocomial infections among hospitalized patients (5). SSI is the most frequent type of healthcare-associated infection on admission and reported as the second most common health care associated infection in Europe and the United States of America. Additionally, in Europe surgical site infection affects more than 500 000 people per year, costing €19 million and in the United States of America leads to patients costing US$ 10 billion a year and spending more than 400 000 extra days in the hospital (5).
SSIs are preventable complications up to 60% following surgery and lead to a signi cant burden in terms of patient morbidity, deaths and raised cost of treatment. Patients who acquire SSIs are 5 times more likely to be readmitted to the hospital, and 2 times more likely to die compared with patients without SSIs (1). However, improvements have been made in infection control practices, including sterilization methods, improved operating room ventilation surgical technique, and still, surgical site infection remain the most common cause of morbidity, prolonged hospitalization, death and associated with nearly 1 million additional inpatient-days worldwide annually (9).
The SSIs in developing countries are on the rise associated with a dramatic increase in patient's morbidity, and mortality and the most frequent type of health care-associated infection and approximately one in 10 people who have surgery acquire surgical site infection (5).
In Africa, the magnitude of surgical site infection ranged from 2.5 to 30.9% and up to 20% of major surgery procedures lead to wound infection (1).
According to a CDC (Center for Disease Control) report in developing country showed that factors associated with surgical site infection were duration of surgery > 1 hour, American Society of Anesthesiologists score > 1, type of wound, use of local anesthesia, patient factors (body mass index > 25kg\m 2 , diabetic mellitus and alcohol) any acute/ chronic medical problem, preoperative hospital stay > 7day (5).
Currently on behave of advances in clinical practices and easy preventive methods in Ethiopia, the magnitude of SSI, complications and burden in terms of patient morbidity, cost of treatment, and mortality rate still critical public health problems (7). The magnitude of surgical site infection is still high, 1l.1% Suhul teaching Hospital (12) and 25.5% in west and east Gojam zone hospitals (7) However, studies are limited in Ethiopia regarding magnitude and associated factors of SSI at general hospitals particularly in study areas. Therefore, this study aims to determine the magnitude and associated factors of SSIs in selected Bale zone general hospitals Southeast Ethiopia. This study would be helpful in developing targeted intervention to reduce occurrence of SSIs.
This study primarily intended to provide information on the magnitude of SSI and associated factors. The study ndings will contribute to improve quality of patient care. The primary bene ciaries of the study were patients and patient family, through improve patient outcomes, decrease health care costs and decrease stress related to SSI which is a priority of governmental. Second bene ciaries of the study were higher authority (hospital administrators, zonal health o ce and regional health Bureau) re plan to undertake precautions and prevention to reduce SSI.
The nding will help the health care provider to put more effort towards utilization of evidence-based on prevention of SSI. As well as essential for developing targeted intervention to reduce its occurrence, to decrease incidence and complications in the meantime related with surgical sites infection. It will also serve as baseline data for those who are interested further research on the issue.

Methods And Materials
Study area and period This study was conducted in Gindhir General Hospital, Bale zone, Oromia region, Southeast Ethiopia. The Hospital 550km from Addis Ababa. Those hospitals give service to approximately 1.5 million patients annually and provide specialized services in four major departments: Pediatrics, surgery, gynecology, obstetrics and internal medicine. This study was conducted from March 1/2020 to April 30, 2020.

Study design
Hospital based cross-sectional study design was conducted.

Source population and Study population
All post-operative patients in Bale zone general hospitals were the source population. All post-operative adult patients who had surgery in Bale Robe and Gindhir General Hospitals in the study period were the study population.

Inclusion and Exclusion criteria
All post operated adult patients in surgical ward (18-65 years) of Gindhir and Bale Robe General Hospitals.
Patient from outpatient department admitted for diagnosis of Surgical site infection who operation done at other hospitals, patient who had implant at the site of operation, severely ill patients and leg amputation.

Sample size determination and Sampling technique
The sample size was determined by using single population proportion formula with the following assumptions: 5% marginal error and 95% con dence interval by considering p-value 25.5% proportion prevalence of postoperative surgical site infection from West and East Gojjam zone hospital (7) the sample size with 105 none response rate was 321. All adult patients who undergone major surgery in the surgical ward of both hospitals were involved in the study.

Study Variables
Surgical site infection is the dependent variable. However, Socio-demographic variables (Age, address, marital status, educational status and monthly income), Patient related factors (Cigarette use, alcohol use, body mass index, and co morbid disease: diabetic mellitus and hypertension), Surgical procedure related factors (Wound type, site of surgery, category of procedure, pre hospital stay, wound class ,type of operation, class ASA index, post hospital stay, preoperative and postoperative hemoglobin, duration of procedure, type of anesthesia, blood loss, prophylactic antibiotic) are independent variables.
Data collection instruments and procedure Data were collected using structured interviewer administered questionnaire. By using standardized questionnaire checklist adapted from Centers for Diseases Control and Prevention surgical site infection criteria. The questionnaire where also adapted from similar study and modi ed to the context of study area after reviewing relevant literatures and guidelines on surgical site infection with modi cation. Questionnaire was used to capture from both the records (chart review) and the patients.
Eligible patients were observed through the postoperative period till discharge from the hospitals for the development of surgical site infection. The questionnaires has four parts: socio demographic information, patient related factors, surgical procedure related factors and surgical site infection related factors. Weight was measured by data collectors using weight scale with patients standing without shoes and wearing light clothing and height was also measured by data collectors by using height scale while the patients standing without shoes and nally body-mass index was calculated.
The patients were followed and reviewed the charts daily after operation until the patients discharge from the hospitals and after discharge until 30 days of operation (follow up at surgical referral clinic). The wounds were examined by using checklist on 3rd, 5th and day of discharge, then after discharge follow up at surgical referral clinic.The data were collected by 4 trained BSc nurses those not working at surgical ward and supervised by two Integrated Emergency Surgery o cer. The patients were advised at the time of discharge to return for post-operative visits on 7, 14 and 25-30 days.

Data processing and analysis
The collected data were coded, cleaned and entered into Epi-data Entry version 3.1 and checked for the consistency of data entry then exported to SPSS version 20.0 for further analysis. Model fitness was checked by the Hosmer-Lemeshow test, which gives evidence of fitness with a predictor test level of p=>0.11. Frequencies and percentages of different variables were determined and odds ratios were calculated to determine the associations. Odds ratios with 95% con dence intervals were computed using binary logistic regression. Bivariable and multivariable logistic regression analysis was used to identify factors related to surgical site infection. In bivariable analysis all variables were entered to the model and variables whose p-value less than 0.25 where entered into multivariable analysis. The crude and adjusted odds ratios together with their corresponding 95% con dence intervals were computed. A P-value < 0.05 was considered declaring a result as statistically signi cant in this study.

Ethical Consideration
Ethical clearance was obtained from MaddaWalabu University institutional review committee, to insure full protection of the rights of study subjects. Participation of patients in this study was entirely voluntary and con dentiality was protected. The right of participants to continue or withdraw to participate was respected and names were not mentioned. Furthermore, individuals who are involved in this study were given using verbal consent as a prerequisite before data collection.

Operational de nition
Alcohol use defined as the current use of alcohol (more than one unit of alcohol for females and more than two units for males per day) for the previous month.
Prophylactic antibiotic: refers to a very brief course of an antimicrobial agent initiated just before an operation begins with an attempt to sterilize tissues.
Cigarette smoking is defined as the current smoking of at least one cigarette per 24 hours.
Pre hospital stay is defined as time from admission of patient up to time of operation.
Post hospital stay is defined as time from operation up to patient discharge.

Results
Socio-demographic characteristics of study population A total of 260 patients were participated in the study which gives a response rate of 90%. Among this 139 (53.5%) were males and more than two-third of the patients were from rural area (66.9%). The mean age of the patients was 40.2 (SD± 14.20) years and nearly one-fourth (25%) of the respondents was can't read and write. Most of the participants were farmer 120 (46.2%)

Magnitude of surgical site infection
Among interviewed patients 24(9.2%) of them were develop surgical site infection. Of these, 13(5%) were develop surgical site infection before discharge from the hospitals. The mean postoperative day surgical site infection detected was 6.9(SD±2.8) days and the mean number of additional postoperative day of hospital stay due to SSIs was13.8 (SD±4.8) days. Nearly, more than two-third of SSI were super cial (87.5%) and only 3(12.5%) were develop deep SSI.

Types of surgical procedure
Abdominal surgeries accounted for the majority of surgical procedure performed in study area 181(69.6%) followed by neck surgery (17.31%).

Surgical procedures related characteristics
One hundred sixty one (61.9%) of surgical procedures were clean-contaminated and most of the operations were emergency 147(56.5%). The mean duration of operation was 52.07 (SD ±13.63) hour, mean duration of preoperative stay was 2.503 (SD±2.08) and that of postoperative stay was 4.11 (SD ± 2.89) days. Majority of patients 208 (80%) received antimicrobial prophylaxis before operation. More than two-third of patients were under ASA score one 224 (86.2%). Majority of the patients were undergone general anesthesia 243 (93.5%). Moreover, more than half of the patients (56.5%) were stays in the hospital ranges 2 to 7 days before operation and patients who stay in the hospital for more than 7 days before operation were 2.7%. Most of the patients (96.2%) were taken postoperative antibiotic for less than 7 days.

Factors associated with surgical site infections
The independent variables which had association with dependent variable in bivariable analysis at Pvalue of less than 0.25 were included in the multivariable logistic regression model. The outcome of the nal backward multivariable logistic regression model showed that ve independent variables were dropped from the nal model. By adjusting potential confounders, body mass index ≥ 25kg\m 2 , co morbid disease and prophylactic antibiotic were statistically signi cant factor associated with surgical site infection at P-value of less than 0.05. Patients whose prophylactic antibiotic administered before operation were eighty 81% percent less likely to develop surgical site infection as compared with patients whose prophylactic antibiotic not administered before operation AOR =0 .

Discussion
This study showed that over all magnitude of surgical site infection was 9.2%. Surgical site infection is one of the most common types of nosocomial infections. This study was conducted to assess surgical site infection after operation procedure among adult patients. In present study an attempt was made to identify magnitude of SSI and associated factors. Preoperative prophylactic antibiotic, body mass index and co morbid disease were signi cant factors associated with surgical site infection.
The surgical site infection rate in this study was comparable with previous study conducted in Pakistan which the rate of surgical site infection was 8.8% (9). Similarly, comparable to study conducted in Ethiopia, with magnitudes of 9.9% in Amhara region public hospitals (14), 10.9% in Bahir Dar North West Ethiopia and 11.1% in Suhul Hospital, Northern Ethiopia (12). The possible reason for this similarity might be due to similar in methods and sample size. But, lower compared to previous study conducted in African country 30.9% in Nigerian hospital (10). 22.6% in Tanta University Hospital of Egyp (6). the difference might be due to different in study period. Similarly, lower than studies conducted in Ethiopia: 13% at Wolaita Sodo University Teaching Hospital (14 and 25.5% in west and east Go jam zone hospitals (7). That difference could be due to difference in hospital level, time, study setting and sample size.
The nding was higher compared with study conducted in large Brazilian hospital the surgical site infection rate was 3.4% (6). This difference in surgical site infection rate in present study might be due to modern instruments, rooms and adequate trained man power and again 5% higher in Hawasa referral hospital (1).
In this study co morbidity was signi cantly found to be predictor of surgical site infection. Patient with co morbidity were 15.8fold risk of developing surgical site infection as compared to those with no co morbidity. In agreement to previous study in west and east Gojam zone hospitals (7) in which patient those had co morbidity were 16.7 times risk to develop surgical site infection as compared with those had no co morbidity and again analogues with study conducted at Assela referral hospital showed that patient with co morbidity had statistically signi cant association with surgical site infection; that is risk of surgical site infection 5.4 fold risk of developing surgical site infection as compare to those with no co morbidity (13).
Present study shows that administration of antimicrobial prophylaxis before operation was revealed to be preventive factor for development of surgical site infection. This study indicates that administration of antimicrobial prophylaxis before operation was eighty 81% less likely to develop surgical site infection as compared with those prophylactic antibiotic not administered before operation. Again in agreement with previous studies conducted in Ethiopia which revealed that if antimicrobial prophylaxis not administered before operation, the risk of developing surgical site infection was 11.10 times compared with those antimicrobial prophylaxes delivered before operation (11). The fact that, if antimicrobial prophylaxis administered earlier to operation, then the tissue as well as serum concentration of antimicrobials is adequate enough to prevent contamination of the wound during the operation until the wound is closed. This rationale was con rmed by one study that indicated the low tissue concentration of antimicrobial at the time of wound closure was independent predictor for development of SSIs (3).
In present study the risk of surgical site infection for those body mass index ≥ 25kg/m 2 were 12.5 times more likely to develop surgical site infection as compared with those body mass index < 25 kg/m 2 . This nding was congruent with study in USA patients with body mass index ≥ 25 kg/m 2 were 1.47 higher risk to develop surgical site infection than patients with body mass index of < 25 kg/m 2 (10).
The information originated from a real practical situation and this study also supported with observational checklist. However, the limitation of the study is variables related to antiseptics used for patient preparation, wound care and techniques used for materials sterilization were not included. Report in this study may still be underestimated due to few planned surgeries were postponed particularly due to pandemic disease (COVID 19).

Conclusion
The magnitude of surgical site infection was relatively high as compared to national standard. The most important factors associated with surgical site infection were co-morbidity, body mass index ≥ 25kg/m 2 and antimicrobial prophylaxis. Based on the ndings of this study, we recommend administering antimicrobial prophylaxis before operation, routinely screen and manage co morbidities and extra measure should be taken in high risk patients (obese and patient with co morbid disease

Declarations
Contributions: NA involved in the study design, data collection, analysis and write-up. AE performed analysis, interpretation of data. MH contributed to the design, draft and revision of the manuscript. All authors approved the nal version.
Availability of the data All the data supporting our ndings of this study are available from the corresponding author upon request Funding: This study no speci c nance from any funding agency.
Competing interests: None declared.
Ethics approval: Ethical clearance was obtained from the institutional review board of Institute of Health, Madawalabu University.
Patient and Public Involvement: Verbal informed consent was obtained from each participant after explaining the purpose of the study. The con dentiality of information obtained from the participants was assured and the study subjects were informed that, they had full right to participate to the study.
Data sharing statement: No additional data are available.