Surveillance and Strict Control Measures Reduce Surgical Site Infection (SSI), Al-Yamamah Hospital, Riyadh, 1996

The reported crude nosocomial infection rate in Al-Yamama Hospital (YH), Riyadh (280 beds, 3 operation rooms) in the first half of 1995 was less than 1.8 per 100 surgeries. There were complaints about increased surgical site infections (SSI) rate; SSI rate has never been calculated. We calculated the SSI rate and studied the impact of intensified surveillance and institution of strict control measures in controlling SSI in the YH during the period between October, 1995 and March, 1996.

A SSI was defined as having purulent discharge and fever (>38.5 °C) 3 days or more after surgery or a bacterial pathogen was isolated form the surgical wound. We reviewed the medical records of all patients who had major surgical operations in YH during the period between October, 1995 and March, 1996.

In contrast to pre-existing SSI surveillance, medical record review revealed 37 (9.1%) SSI among 405 surgeries; caused by 7 different bacterial pathogens, predominantly Staphylococcus aureus. SSI rates were higher for elective surgery (12.3%, 14 out of 114) than for emergency surgery (7.9%) (p<0.05). The mean (+ SD) duration of hospitalization in days was longer for patients with SSI in comparison to those with clean surgery (11 vs. 8; p< 0.05, t-test), and 5 (62.5%) out 8 patients, re-admitted to the hospital, had SSI (p<0.05, Fisher's exact test). SSI rates did not differ by operation rooms, surgeons, or having gestational diabetes. Deviations from correct aseptic surgical practices were identified. These included observing that masks did not always cover the nose, change to scrub suit was not 100%, and scrub suits were worn to emergency rooms and wards. The SSI problem was discussed with the Infection Control Committee and the surgical staff in the hospital; and a circular was passed to all doctors and nurses to remind them about strict corrective measures, and a SSI surveillance system was activated. The improved surveillance detected only one (1.1%) SSI out of 99 surgeries made in the five weeks following institution corrective measures that emphasized wearing masks and gowning.

SSI, formerly called surgical wound infections, are the second most site for nosocomial infections, second only to infections of the urinary tract. The data from Al-Yamama hospital indicated that establishing good surveillance and infection control programs helped detect increased SSI rates, brought SSI to the attention of surgical staff, monitored appropriate use of anti-microbial prophylaxis, and reduced cost associated with prolonged hospital stay. SSI programs and feedback to surgeons has lowered the SSI rate by 35% in some other studies [1]. This is probably because surgeons identify probable errors in their techniques or because of an "anxiety" factor as surgeons become aware that their patients' outcome are being monitored [1].

Data from Al-Yamama Hospital showed that the SSI rates were higher for elective surgery as compared with emergency surgery. However, even after adjustment for potentially confounding variables, recent studies consistently found that prolonged preoperative hospital stay is an independent risk factor for SSI. This is attributed to probable alteration of normal flora by antibiotics, acquisition of hospital-acquired multi-resistant pathogens or exposure of the patient to interventions that adversely affect the host resistance. It was found that the ideal for elective operation would be to admit patients to the hospital on the morning or on the day prior to operation [1].

Some published studies questioned the importance of surgical masks as infection control measure. It is worth mentioning that the most important role of surgical masks is to prevent contamination of the mucous membranes of the operating team [1]. There are well documented host factors for SSI in clinical and epidemiologic studies. These included advanced age, morbid obesity, and the presence of remote infections at other body sites are. Surgical-related factors included surgical site class, prolonged pre-operative stay, shaving by razor (especially at prolonged intervals before surgery), prolonged duration of surgery, and the non-use of appropriate use of prophylactic antibiotics. However, the evidence for diabetes, malnutrition, cancer, and immunosuppression are not as well supported.