Blefjell Hospital, Kongsberg, is a medium-sized local hospital. Between 1 700 and 2 000 large and small operations are performed in the surgical department annually; and between 1 000 and 1 100 operations in the outpatient department. The choice of type of operation to record was based on three considerations: that orthopaedic surgery involves a relatively large part of the hospital; that infections after orthopaedic surgery have important consequences and that SSIs in orthopaedic patients are considered to be a good indicator of quality. In the period 2001 - 03, infections were also recorded after operations for hernia, varicose veins, breast tumour, hallux valgus and the removal of fracture fixation implants (a total of 315 patients). There is a lot of work involved in post discharge surveillance and the frequency of infection was relatively low (four deep and six superficial infections), so we decided to stop monitoring these operations.
The strength of the study is that all the patients were monitored for four weeks postoperatively and the follow-up was almost 100 %. The follow-up was demanding because the recording depended on many links both within and outside the hospital. It was made more difficult by the negative attitudes of certain orthopaedic and general surgeons and among the nursing staff. The report forms were not filled in, torn in shreds or boycotted in some other way. All patients that were meant to be included were registered anyway because the nurse regularly checked the operation records. It could not be taken for granted that infections arising after the four weeks would be reported to the hospital. Much of the nurse’s time was spent on following up the report forms both internally in the hospital and after discharge.
Postoperative hospitalisation is ever shorter. The high number of infections after discharge underlines the importance of monitoring patients also after their time in hospital. This fact is supported by other studies (1, 5, 7).
Similar studies at other Norwegian hospitals have not previously been published. This makes it hard to be certain of what our figures actually say about the hospital’s standard. After the introduction of preventive measures in 1999 and 2000, there was a temporary reduction in infections. From 2001 the number of hospital surgeons rose and as a result there were more operations. Uncemented total hip replacements were mainly used.
During the second and third quarter of 2003, unacceptable numbers of deep infections were recorded for total hip replacements. Elective orthopaedic implant surgery was therefore moved from theatre 3 to theatre 1. This had an adjacent room and the possibility of bringing in equipment through airlocks during operations. When the 2003 total hip replacement results emerged, during spring 2004, still with an unacceptably high deep infection frequency, it was decided to stop these operations in the general surgery department. They were moved to the outpatient centre because the operating theatres there had a Weiss ceiling with about 20 changes of air per hour. The same staff performed the operations. The change of theatre did not lead to any change in the frequency of infections following hip implants.
The Norwegian Arthroplasty Register’s report for 2005 shows that the incidence for primary total implant reoperations caused by deep infections, has lain between 1.3 % and 2.0 % in recent years (8). The figures for deep infection recorded in the hip register are based on implant replacement. It is believed that these figures represent about half of the deep hip prosthesis infections. This agrees with our findings. Of our in all 28 deep infections, revision with replacement of implants was performed on 14 patients. The others were successfully treated with local debridement and antibiotics. The figures in the national arthroplasty register come from all Norwegian hospitals and represent both combined and purely orthopaedic departments. On the basis of these figures and the type of surgical departments, one can estimate the expected frequency of postoperative deep infections to be 2 - 4 %.
The quarterly reports show great fluctuations. It is important to be aware of this when assessing the three months’ infection record now to be reported. When a sufficiently high number of hospitals participate in the recording, we will have a reasonably good measurement of the hospitals’ average standard. An evaluation of one hospital against another on the basis of quarterly analysis can be misleading. In the monitoring of surgical site infections it is important to analyse the deep and superficial infections separately. Deep infections are believed to arise peroperatively and cause the greatest stress both for patients and society (5).
Our finding, which indicates a link between the surgeon and deep infection after primary total hip replacement, is sensitive and challenging. Cruse & Foord, who also documented a surgeon factor, point out that extremely thorough operation techniques reduce the risk of postoperative infection. The number of deep surgical site infections ought to result in more attention to operation techniques. This is the responsibility of both the surgeon and the head of department.
We found no connection between the number of superficial and deep infections with individual surgeons. This may indicate that superficial infections, most probably, result from postoperative treatment, washing, bandage changing etc. on the wards and in the convalescent homes, and the patients’ own personal hygiene. Superficial infections represent a risk and should not be trivialized.
The 1 430 extra days in hospital because of hip infection are equivalent to new total hip replacements for 29 patients. With a hospital reimbursement (diagnosis-related-group) of (on average) 50 % of the actual costs, this represents a loss of income for the hospital of around 2 million kroner annually.