Journal
of Hospital
Infection
(1992) 21, 79-83
SHORT
Postoperative hospital A. T. A. Eltahawy”,
REPORT
wound infection at a university in Jeddah, Saudi Arabia A. ‘4. Mokhtarj-, Ragaa ,4. A. Bahnassy$
M. F. KhalaP
and
“Department of Microbiology, King Abdulaziz University Hospital. P.O. Box 6615, Jeddah-21452, TDepartment of Swgery, College of Medicine, k-ing Abdulaziz University, P.O. Box 9029, Jeddah-21413. JDepartment of Community Medicine and Primary Health Care, College of Medicine, King Abdulaziz University, P.O. Box 9029, yeddah-21413, Saudi Arabia. Accepted for publication
7 February
1992
Summary: A prospective study was made of 1418 surgical wounds at the 250-bed King Abdulaziz University Hospital in Jeddah, Saudi Arabia. Daily examinations of wounds, cultures of all suspicious wounds and 28 days outpatient clinic follow-up were performed. The overall infection rate was 9%. The infection rate after clean surgery was 9.5%. High rates of infections were noted after colon resection (19%), caesarean section (19%), abdominal hysterectomy (10%) and cholecystectomy (10%). The infection rates after appendectomy, mastectomy and herniorrhaphy were approximately 7%. A lower rate of infection was seen after thyroidectomy (2%). The incidence of infection was significantly related to pre-operative stay in hospital and to duration of operation.
Introduction
In spite of modern standards of preoperative preparation, antibiotic prophylaxis and advances in anaesthetic and operative techniques, postoperative wound infections still remain a major problem associated with significant morbidity and mortality. * Many factors affect the incidence of surgical wound infection, in addition to the surgeon’s skill and the hospital environment. Host attributes, such as age over 60 years, diabetes mellitus, malignant disease, obesity, malnutrition, length of preoperative stay or pre-existing infection may influence risk, as may such operation characteristics as site, urgency, duration and time of skin shaving.24 Surgical wound infection is the second most frequently encountered hospital-acquired infection at King Abdulaziz University Hospital (KAUH). This study reports a 2-year prospective postoperative wound Correspondence 0195-6701/92/050079+05
to: Dr A. T. A. Eltahawy. $03.00/O
0 I997 The Hoapd
79
Infection
Smery
80
A. T. A. Eltahawy
et al.
surveillance programme initiated in August 1987 at KAUH, which has 250 beds (92 surgical or gynaecological) and three operating theatres. The aim was to determine the rate of infection and the factors that influence the infection rate, to obtain statistical background for future investigation of variables and to improve our infection rate and bed utilization. Methods
All operations that were performed at KAUH between August 1987 and July 1989 were included except oral, rectal and vaginal operations, transurethral resection of the prostate, burn treatments and circumcisions. Wounds were observed by an infection control nurse daily during the patients’ stay in hospital. After discharge, wounds were inspected at each follow-up outpatient attendance and for at least 28 days postoperatively. Microscopy and aerobic and anaerobic cultures were performed on a specimen from any wound that appeared inflamed and demonstrated drainage of any type within 4 weeks of operation. The definition of wound infection proposed by the Centers for Disease Control was used. This requires purulent drainage or a positive culture or a deliberately opened wound or a surgeon’s diagnosis.5 Operations were classified into clean, clean-contaminated, contaminated and dirty as defined by the National Research Council.2 Information recorded on worksheets included the patient’s characteristics, such as age, sex, weight and underlying diseases, and patient-care variables such as preoperative hospitalization, hair removal, type of surgery, length of operation, presence of drains and type of drainage. The x2 test was used to test association between the infection rate and the length of the operation, the length of preoperative stay, insertion of drains and types of drainage. The t-test was used to compare the mean days of stay following the operation for both infected and non-infected wounds. Results
Over the 2-year study period, there were 127 wound infections in 1418 wounds, an overall infection rate of 9% (Table I). Infection rates for certain commonly performed surgical procedures are listed in Table II. Herniorrhaphy was the most common operation at KAUH, accounting for 21% of the operations performed. Cholecystectomy, caesarean section and of the appendectomy accounted for 16%) 15% and 5.5% respectively, operations carried out. High rates of infection were noted in the following operations: colon resection (18.7), caesarean section (18.7), abdominal hysterectomy (10.4%) and cholecystectomy (10.1). The infection rates after appendectomy, mastectomy and herniorrhaphy were 6.6%) 6.9% and 7.4% respectively. A low rate of infection was seen after thyroidectomy (1.9%). The frequency of recovery of the four most common organisms causing wound infection in the study were Staphylococcus aUreUS (41%), dominant
Postoperative Table
wound
I. Incidence
Classification of operative procedure5
78
Clean-contaminated Contaminated
81
of wound infection
Infected No. %
Clean
infection
Not infected No. %
Total
9.5
742
90.5
820
34
6.3
510
93.7
544
10
21.3
37
78.7
47
Dirty
5
71.4
2
28.6
7
Total
127
9.0
1291
91.0
1418
Table Type
II.
of operation
Appendectomy Cholecystectomy Caesarean section Abdominal hysterectomy Colon resection Herniorrhaphy Mastectomy Orthopaedic operations Splenectomy Thoracotomy Thyroidectomy Stomach and oesophagus operations Urological operations Others Total
Infection
rates for common surgical Infected No. % 5 22 39 5 6 21 4 8
procedures
Not infected No. %
Total
ii
6.6 10.1 18.7 10.4 19.4 7.4 6.9 4.6 0 0
71 196 170 43 25 262 54 165 14 4
93.4 89.9 81.3 89.6 80.6 92.6 93.1 95.4 100 100
76 218 209 48 31 283 58 173 14 4
01
01.9
53 54
98.1 100
:t
9 7 127
7.1 10.0 9.0
117 63 1291
92.9 90.0 91.0
126 70 1418
on sites other than the gastro-intestinal tract, Klebsiella and spp. (1 S%), Escherichia coli (12%) and Pseudomonas species (9%). A significant relationship between operations with a duration of more than 2 h and an increase in the postoperative wound infection rate was observed in patients undergoing cholecystectomy, mastectomy and appendectomy; the infection rates for operations of more than 2 h vs. less than 2 h were: cholecystectomy-54.6%, (12/22) vs. 25%, (49/196) [x2 = 8.57, P-C 0.011 mastectomy-SO% (2/4) vs. 5.6% (3/54) [corrected x2=455, P
of Hospital
Infection
(1992) 21, 79-83
SHORT
Postoperative hospital A. T. A. Eltahawy”,
REPORT
wound infection at a university in Jeddah, Saudi Arabia A. ‘4. Mokhtarj-, Ragaa ,4. A. Bahnassy$
M. F. KhalaP
and
“Department of Microbiology, King Abdulaziz University Hospital. P.O. Box 6615, Jeddah-21452, TDepartment of Swgery, College of Medicine, k-ing Abdulaziz University, P.O. Box 9029, Jeddah-21413. JDepartment of Community Medicine and Primary Health Care, College of Medicine, King Abdulaziz University, P.O. Box 9029, yeddah-21413, Saudi Arabia. Accepted for publication
7 February
1992
Summary: A prospective study was made of 1418 surgical wounds at the 250-bed King Abdulaziz University Hospital in Jeddah, Saudi Arabia. Daily examinations of wounds, cultures of all suspicious wounds and 28 days outpatient clinic follow-up were performed. The overall infection rate was 9%. The infection rate after clean surgery was 9.5%. High rates of infections were noted after colon resection (19%), caesarean section (19%), abdominal hysterectomy (10%) and cholecystectomy (10%). The infection rates after appendectomy, mastectomy and herniorrhaphy were approximately 7%. A lower rate of infection was seen after thyroidectomy (2%). The incidence of infection was significantly related to pre-operative stay in hospital and to duration of operation.
Introduction
In spite of modern standards of preoperative preparation, antibiotic prophylaxis and advances in anaesthetic and operative techniques, postoperative wound infections still remain a major problem associated with significant morbidity and mortality. * Many factors affect the incidence of surgical wound infection, in addition to the surgeon’s skill and the hospital environment. Host attributes, such as age over 60 years, diabetes mellitus, malignant disease, obesity, malnutrition, length of preoperative stay or pre-existing infection may influence risk, as may such operation characteristics as site, urgency, duration and time of skin shaving.24 Surgical wound infection is the second most frequently encountered hospital-acquired infection at King Abdulaziz University Hospital (KAUH). This study reports a 2-year prospective postoperative wound Correspondence 0195-6701/92/050079+05
to: Dr A. T. A. Eltahawy. $03.00/O
0 I997 The Hoapd
79
Infection
Smery
80
A. T. A. Eltahawy
et al.
surveillance programme initiated in August 1987 at KAUH, which has 250 beds (92 surgical or gynaecological) and three operating theatres. The aim was to determine the rate of infection and the factors that influence the infection rate, to obtain statistical background for future investigation of variables and to improve our infection rate and bed utilization. Methods
All operations that were performed at KAUH between August 1987 and July 1989 were included except oral, rectal and vaginal operations, transurethral resection of the prostate, burn treatments and circumcisions. Wounds were observed by an infection control nurse daily during the patients’ stay in hospital. After discharge, wounds were inspected at each follow-up outpatient attendance and for at least 28 days postoperatively. Microscopy and aerobic and anaerobic cultures were performed on a specimen from any wound that appeared inflamed and demonstrated drainage of any type within 4 weeks of operation. The definition of wound infection proposed by the Centers for Disease Control was used. This requires purulent drainage or a positive culture or a deliberately opened wound or a surgeon’s diagnosis.5 Operations were classified into clean, clean-contaminated, contaminated and dirty as defined by the National Research Council.2 Information recorded on worksheets included the patient’s characteristics, such as age, sex, weight and underlying diseases, and patient-care variables such as preoperative hospitalization, hair removal, type of surgery, length of operation, presence of drains and type of drainage. The x2 test was used to test association between the infection rate and the length of the operation, the length of preoperative stay, insertion of drains and types of drainage. The t-test was used to compare the mean days of stay following the operation for both infected and non-infected wounds. Results
Over the 2-year study period, there were 127 wound infections in 1418 wounds, an overall infection rate of 9% (Table I). Infection rates for certain commonly performed surgical procedures are listed in Table II. Herniorrhaphy was the most common operation at KAUH, accounting for 21% of the operations performed. Cholecystectomy, caesarean section and of the appendectomy accounted for 16%) 15% and 5.5% respectively, operations carried out. High rates of infection were noted in the following operations: colon resection (18.7), caesarean section (18.7), abdominal hysterectomy (10.4%) and cholecystectomy (10.1). The infection rates after appendectomy, mastectomy and herniorrhaphy were 6.6%) 6.9% and 7.4% respectively. A low rate of infection was seen after thyroidectomy (1.9%). The frequency of recovery of the four most common organisms causing wound infection in the study were Staphylococcus aUreUS (41%), dominant
Postoperative Table
wound
I. Incidence
Classification of operative procedure5
78
Clean-contaminated Contaminated
81
of wound infection
Infected No. %
Clean
infection
Not infected No. %
Total
9.5
742
90.5
820
34
6.3
510
93.7
544
10
21.3
37
78.7
47
Dirty
5
71.4
2
28.6
7
Total
127
9.0
1291
91.0
1418
Table Type
II.
of operation
Appendectomy Cholecystectomy Caesarean section Abdominal hysterectomy Colon resection Herniorrhaphy Mastectomy Orthopaedic operations Splenectomy Thoracotomy Thyroidectomy Stomach and oesophagus operations Urological operations Others Total
Infection
rates for common surgical Infected No. % 5 22 39 5 6 21 4 8
procedures
Not infected No. %
Total
ii
6.6 10.1 18.7 10.4 19.4 7.4 6.9 4.6 0 0
71 196 170 43 25 262 54 165 14 4
93.4 89.9 81.3 89.6 80.6 92.6 93.1 95.4 100 100
76 218 209 48 31 283 58 173 14 4
01
01.9
53 54
98.1 100
:t
9 7 127
7.1 10.0 9.0
117 63 1291
92.9 90.0 91.0
126 70 1418
on sites other than the gastro-intestinal tract, Klebsiella and spp. (1 S%), Escherichia coli (12%) and Pseudomonas species (9%). A significant relationship between operations with a duration of more than 2 h and an increase in the postoperative wound infection rate was observed in patients undergoing cholecystectomy, mastectomy and appendectomy; the infection rates for operations of more than 2 h vs. less than 2 h were: cholecystectomy-54.6%, (12/22) vs. 25%, (49/196) [x2 = 8.57, P-C 0.011 mastectomy-SO% (2/4) vs. 5.6% (3/54) [corrected x2=455, P
