Adherence to local hospital guidelines for surgical antimicrobial prophylaxis: a multicentre audit in Dutch hospitals

M. E. E. van Kasteren1,*, B. J. Kullberg1, A. S. de Boer2, J. Mintjes-de Groot3 and I. C. Gyssens4

1 Department of Internal Medicine 541, University Medical Centre Nijmegen, and Nijmegen University Centre for Infectious Diseases, P.O. Box 9101, 6500 HB Nijmegen; 2 National Institute for Public Health and the Environment, RIVM, Bilthoven; 3 Dutch Institute for Healthcare Improvement, CBO Utrecht; 4 Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands

Received 14 November 2002; returned 1 January 2003; revised 25 March 2003; accepted 25 March 2003


    Abstract
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Objective: To study the adherence to local hospital guidelines for antimicrobial prophylaxis in surgery, and explore reasons for non-adherence.

Methods: A prospective, multicentre audit of elective procedures, without prior suspicion of infection, was carried out in 13 Dutch hospitals. By reviewing medical, anaesthetic and nursing records, and medication charts, the prescription of antibiotics was compared with the local hospital guideline on antibiotic choice, duration of prophylaxis, dose, dosing interval and timing of the first dose.

Results: Between January 2000 and January 2001, 1763 procedures were studied. Antibiotic choice, duration, dose, dosing interval and timing of the first dose were concordant with the hospital guideline in 92%, 82%, 89%, 43% and 50%, respectively. Overall adherence to all aspects of the guideline, however, was achieved in only 28%. The most important barriers to local guideline adherence were lack of awareness due to ineffective distribution of the most recent version of the guidelines, lack of agreement by surgeons with the local hospital guidelines, and environmental factors, such as organizational constraints in the surgical suite and in the ward.

Conclusion: This study shows that, although adherence to separate aspects of local hospital guidelines for surgical prophylaxis in the Netherlands is favourable, overall adherence to all parameters is hard to achieve. Adherence to guidelines on dosing interval and timing needs improvement, in particular. To increase the quality of antimicrobial prophylaxis in surgery, effort should be put into developing guidelines acceptable to surgeons, in adequately distributing the guidelines and to facilitating logistics. Audits of surgical prophylaxis may help hospitals identify barriers to guideline adherence.

Keywords: antibiotic policy, adherence


    Introduction
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
The use of antimicrobial prophylaxis for selected surgical procedures is one of the measures used to prevent the development of a surgical site infection (SSI).1 In past decades, many papers have decribed optimal prophylaxis, and guidelines for surgical prophylaxis have been developed.16 Despite the availability of these guidelines, recent studies assessing the current practice of prophylaxis throughout the world have shown that over-consumption of antimicrobial drugs and inappropriate timing remain a problem in surgical prophylaxis.714 Historically, the Netherlands has a restrictive antibiotic policy.15 Nevertheless, misuse of antibiotics has been reported in Dutch hospitals. An intervention study, which analysed antibiotic utilization in surgical departments of a single university hospital in the Netherlands between 1990 and 1992, showed that over-consumption and suboptimal timing of antibiotics for surgical prophylaxis was found in up to 66% and 56% of the procedures, respectively.16,17 Since the early 1990s, most hospitals in the Netherlands have developed local hospital guidelines to improve the quality of prophylaxis. However, quality improvement is not confined to guideline development. Facilitation of adherence to these guidelines, and their effective implementation, are as important.18 Since the latter is often underestimated, many guidelines are abandoned in daily practice. In 1999, the CHIPS (surgical prophylaxis and surveillance) project, an audit and improvement programme looking at the quality of surgical prophylaxis related to SSI, was started in the Netherlands. Part of this project was to study the adherence to local hospital guidelines for prophylaxis, and to explore reasons for non-adherence. The results are presented in this paper.


    Methods
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Frequently performed surgical techniques, for which the efficacy of antibiotic prophylaxis has been researched extensively in well conducted trials, were selected for this prospective, multicentre study. To observe normal daily routine, only elective procedures were included. Four major surgical disciplines were audited, and techniques with a differing intrinsic risk for SSI were selected. In orthopaedic and vascular surgery, procedures classified as ‘clean’19 included total hip implant, femoral hemiprosthesis, grafting of the aorta and femoropopliteal and femorotibial bypass. In gynaecological and intestinal surgery, approaches classified as ‘clean–contaminated’19 included abdominal and vaginal hysterectomy with or without vaginal repair, and various colorectal procedures. To avoid difficulties in discriminating prolonged prophylaxis from post-operative therapy, procedures with suspected or established infection during surgery were excluded. The study was conducted in 13 hospitals participating in a national survey of SSI, the PREZIES project.20 The hospitals represented inpatient care in the Netherlands, since university, non-university teaching and non-teaching hospitals were included.

Between January 2000 and January 2001, adherence to local guidelines for antimicrobial surgical prophylaxis in these hospitals was reviewed. The study period per hospital varied between 6 and 10 months depending on the incidence of the selected procedures in the hospitals. The following aspects of antimicrobial prophylaxis were audited: antibiotic choice, duration, dose, interval between doses, timing of first dose and antibiotic choice in case of allergy. Wound class,19 physical condition of the patient according to the classification of the American Society of Anesthesiologists (ASA score),21 time of induction of anaesthesia, time of the first incision and the duration of the procedure were recorded. Data were collected by infection control practitioners from medical, anaesthetic and nursing records, and medication charts. Before the start of the project, as well as during the study, data collection was validated at regular intervals (M. E. E. van Kasteren, A. S. de Boer, M. Ridderhof-van’t Veer, J. Mannien, J. Wille, B. J. Kullberg & I. C. Gyssens, unpublished data). Each hospital was requested to provide their most recent version of local guidelines for prescription of surgical prophylaxis. Only guidelines composed by the committees for antibiotic policy of the participating hospitals, printed in an official hospital guide for antibiotic prescription, were considered. The prophylaxis actually given was assessed according to these guidelines by the same investigator for all procedures. A modified standardized qualitative method for evaluation was used.22 The criteria for evaluation of adherence are summarized in Table 1.


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Table 1.  Criteria for assessment of adherence to local guidelines
 
Courses of antimicrobial drugs were evaluated. If more than one drug was prescribed for a single procedure, all parameters were evaluated separately for each drug. Subsequently, a final assessment of the antibiotic course was composed by combining these separate drug evaluations. Any divergence from the guideline in the prescription of one of the drugs led to a final assessment of the prophylactic course as discordant with the guideline. If no antibiotic prescriptions had been recorded, it was assumed that antibiotics were not given. If data on a certain parameter of the antibiotic prescription were lacking, this was classified as missing data on this parameter only. If an antibiotic was given while it was not indicated, the parameters of antibiotic choice, duration, dose, dosing interval and timing were not evaluated.

The infection control practitioners collected data prospectively using standardized forms. These data were entered in a database, double-checked by the investigator and infection control practitioner of the project, and analysed using SPSS 10.0.


    Results
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Between January 2000 and January 2001, 1763 surgical procedures were recorded in 13 Dutch hospitals. Table 2 shows the demographic data of the patients and the distribution of the procedures according to surgical specialty and wound class. Not every hospital performed all types of procedures. Almost two-thirds of the procedures were clean, and the majority were orthopaedic. The main features of the guidelines obtained from the participating hospitals are summarized in Table 3.


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Table 2.  Demographic data
 

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Table 3.  Local hospital guidelines for surgical prophylaxis in the participating hospitals
 
Overall assessment of all parameters

In 1598 out of 1763 procedures (91%), data on all parameters of prophylaxis were available and a complete evaluation could be performed. In 439 procedures (28%), there was full adherence to local guidelines for all parameters. Without including the dosing interval for antibiotics given in the ward or in the operating theatre, prophylaxis was completely concordant with the guidelines in 543 cases (34%). Parameters were also evaluated separately, so that missing data of one parameter did not preclude assessment of the other.

Indication

Procedures for which antibiotics are generally indicated were selected, although one hospital’s local guidelines recommended no prophylaxis for abdominal hysterectomy (unless performed for carcinoma). According to the hospital guidelines, antibiotics were indicated in 1737 procedures. In 33 procedures (2%), no prophylaxis was given, and in 17 procedures (1%), one out of two drugs was omitted.

Antibiotics were administered in 1712 procedures. In eight of these procedures, no antibiotics were recommended. These were all abdominal hysterectomies performed in the one hospital that did not recommend prophylaxis. In 11 cases, two types of antibiotic were administered, whereas only one was indicated. In one case, three types of antibiotic were administered, whereas only two were indicated. So in 1704 procedures, at least one antibiotic was indicated and, when available, data on antibiotic choice, duration, dose, dosing interval and timing were evaluated (Table 4).


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Table 4.  Non-adherence to local guidelines for prophylaxis according to the assessment defined in Table 1
 
Antibiotic choice

In 1560 of 1689 evaluable procedures (92%), antibiotic choice was concordant with the hospital guideline and discordant in 129 (8%) (Table 4). More than 80% of the discordant cases were reported in two hospitals (F and H). In these hospitals, the antibiotic choice was discordant in more than 30% of the procedures because the surgeons used a protocol that differed from the guideline issued by the hospital committee for antibiotic policy. The adherence of the surgeons to their own protocol was 100%. The remaining errors were incidental and almost equally distributed over the hospitals. In many instances where an allergy to ß-lactams was suspected, antibiotic choice was incorrect. In 15 cases, the antibiotic choice could not be evaluated because the hospital guideline did not provide an alternative for allergy to the primary drug of choice.

Duration

In 1389 of 1688 evaluable procedures (82%), duration was concordant with the hospital guideline. In 257 procedures (15%), duration was longer than recommended and shorter in 42 (3%) (Table 4), including eight procedures in which a second dose was not administered during prolonged surgery. In three hospitals (C, H and L), more than 25% of the prescriptions were continued longer than recommended (range 25–50%). In hospital C, the prolonged use was fully attributable to orthopaedic surgeons, who followed their own protocol rather than the hospital guideline. Adherence to this protocol was almost 100%. In hospital H, deviation from the hospital guideline was unintentional, and the result of inaccurate ‘stop’ orders for antibiotics in the ward. In hospital L, local hospital guidelines were violated because some surgeons felt insecure about the length of prophylaxis recommended by these guidelines.

In 16 cases (1%), duration could not be evaluated because medication charts were incomplete.

Dose

In 1461 of 1636 evaluable procedures (89%), the dose was concordant with the local hospital guidelines. In 15 procedures (1%), the dose was lower and in 123 (8%) higher than recommended (Table 4). Higher doses were mainly recorded in one hospital (F), in all participating specialties. In 37 procedures (2%), performed in hospital J, the dose of one of the agents was too high and of the other too low. Reasons for incorrect dosing were: application of outdated guidelines instead of the most recent version in hospitals F and J, and deliberate use by orthopaedic surgeons in hospital F of doses higher than recommended in the hospital guidelines. In 68 of 1704 procedures (4%), data on dosing were missing, or the hospital recommendation was incomplete. In almost half of the hospitals that provided guidelines of what to administer in case of allergy to the primary drug of choice, dosing recommendations for these alternative drugs were lacking.

Dosing interval

In 835 of 1704 procedures (49%), more than one dose was administered. Of these, the dosing interval of antibiotics repeated during surgery or on the ward could be calculated in 802 procedures. In 345 procedures (43%), dosing intervals were concordant with the guidelines and discordant in 457 (57%) (Table 4). In seven hospitals, more than 50% of the dosing intervals were discordant with the guideline, and in four hospitals (G, H, I and L) almost all intervals were incorrect. Most errors were because of administration of antibiotics by nurses on the ward at fixed clock rounds, instead of adjusting this to the time of the previous dose.

In 55 of the evaluable cases, antibiotic doses were repeated during surgery. In six cases (11%), the interval exceeded the recommended interval.

Timing

In 809 of 1619 evaluable procedures (50%), timing was concordant with the hospital guideline. Timing was earlier than recommended in 358 (22%) procedures and later in 448 (28%) (Table 4). In four procedures, timing of one of the drugs was too early and of the other too late.

In three hospitals (B, F and I), an assessment of ‘timing too early’ could not be made, since specific recommendations for the timing of the first dose other than ‘before the incision’ were not given (Table 3). In three hospitals (G, H and K), prophylaxis was administered earlier than recommended in more than 80% of the cases. In eight hospitals, prophylaxis was administered later than recommended in more than 25% of the procedures. There was a striking difference in timing per specialty. In general, timing in orthopaedic procedures was earlier than recommended. However, in intestinal and gynaecological surgery, timing of the first dose was later than recommended in more than 50% of the cases. This pattern was observed in almost all hospitals. Errors in timing were mainly due to logistics in the surgical suite and not because of deliberate deviation from the guidelines. The time of arrival at the operating complex and the type of anaesthesia, epidural or general anaesthesia, was an important determinant for timing of the first dose. In one hospital (H), timing was too early for almost all procedures because the first dose of prophylaxis was given on the ward instead of in the operating theatre. In 85 of 1704 procedures (5%), data on timing were missing because the moment of the first incision, or the moment of the administration of the first antimicrobial dose, could not be retrieved from the records.


    Discussion
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
The present study demonstrates that, although in the Netherlands adherence to separate aspects of prophylaxis was favourable, adherence to all aspects of a guideline for surgical prophylaxis was difficult. It is noteworthy that the criteria for assessment of adherence were strict, and that the guidelines recommended a prudent use of antibiotics. Taking into account the adherence in some hospitals to non-official hospital guidelines drawn up by surgeons, it can be concluded that the willingness to adhere to guidelines in general is good. Hardly any variation in antibiotic choice, dose and duration were observed that were based on individual decisions of surgeons. In only one hospital (L), did surgeons decide individually to extend the duration of prophylaxis. A study by Motola et al.14 showed that in Italy the willingness to adhere to guidelines is disappointing.

In contrast to the present study, most studies in other countries have assessed the quality of prophylaxis according to an international or a national standard. Only a few have studied adherence to local guidelines.2325 One report from a tertiary teaching hospital in Brazil23 showed that in only 3% of the procedures prophylaxis was given according to hospital guidelines, in terms of antibiotic choice, duration, dose and timing. In the present study, concordance with local guidelines on antibiotic choice, duration, dose and timing was 34%. In the study by Finkelstein et al.,25 performed in Israel, adherence to duration and timing was comparable to the present study. In the study by Vaisbrud et al.,24 also performed in Israel, the adherence was slightly better, especially for timing of the first dose.

Guideline adherence can be hindered by various barriers.26,27 In exploring these barriers in the present report, the process of guideline development and distribution was studied. With a few exceptions, guidelines were revised regularly (Table 3), but revised versions did not always reach the people that had to use them. In some hospitals, several revised versions of a guideline were distributed within a short time, leading to confusion about which one to apply. Sometimes, a revised version of the hospital guideline was printed in the antimicrobial hospital guide without changing local protocols on the ward, or without updating reminders in the operating theatre. This lack of awareness of the appropriate guideline was the main barrier to guideline adherence regarding antimicrobial choice and dose. Acquaintance may be improved by electronic distribution of the guidelines, and by pre-printing sections of the guideline on prescription charts.

Some hospital committees continued to produce guidelines with which they knew surgeons disagreed. In two hospitals, lack of agreement by the orthopaedic surgeons with the recommended duration of prophylaxis was the most important barrier to adherence to the local hospital guideline. Testing the feasibility and acceptance of clinical guidelines among the target group is important for effective implementation.18,28,29 It is just as important to ensure that recommendations in the guideline agree with the current evidence base, and that links between recommendations and scientific evidence are made explicit.30 Therefore, more effort should be put into providing surgeons with evidence of the content of the guideline and in trying to achieve consensus, before implementing new guidelines. Finally, antibiotic policy makers are often unaware of logistical problems in the surgical suite or in the ward. Logistical constraints were the most important barriers to adherence to guidelines for timing and dosing intervals. The difference in time of arrival at the operating complex could have been responsible for most variations in timing of the first antibiotic dose between orthopaedic surgery versus gynaecological and intestinal surgery. Studying these logistical constraints in more detail can help to create conditions that facilitate guideline adoption.

Our study has several limitations. First, the hospitals participating in this study comprised only 10% of the hospitals in the Netherlands. However, the selection seems to represent daily practice, since the number of procedures recorded was large, different specialties were represented in different types of hospital and the geographic distribution of the hospitals was wide. Nevertheless, since participation was voluntarily, it is possible that we have included a favourable selection of hospitals, and that adherence to local guidelines in other Dutch hospitals may be poorer in comparison. Second, adherence to guidelines does not automatically imply that the quality of surgical prophylaxis is optimal, and inappropriate guidelines may explain some of the deviation in practice from guidance. To evaluate this, a critical appraisal of the content of the guidelines is needed. However, focussing only on the content of guidelines, without paying attention to their adoption, is a major reason for the failure of guidelines as an instrument for quality improvement, and therefore both processes are needed.18 For most hospitals in this study, several problems of adherence to guidelines were similar, and therefore this study might provide general information for those involved in quality improvement of surgical prophylaxis. Other problems seemed specific to the local situation. For this reason and for constant reinforcement of guidelines, repetitive audits of surgical prophylaxis are recommended. Since these studies are time-consuming, adequate financial resources are required.

In conclusion, this study shows that in the Netherlands, willingness to adhere to guidelines for surgical prophylaxis is good. To achieve optimal adherence, antibiotic policy makers should develop evidence-based guidelines in unison with surgeons, guarantee an effective distribution of the guidelines and facilitate situations to make them more applicable.


    Acknowledgements
 
We are grateful to the infection control practitioners of the participating hospitals for retrieving the surgical prophylaxis data: Mr F. Verhoef, Rijnland Hospital, Leiderdorp; Mrs A. Gosselink-Franssen, University Medical Center Leiden; Mrs L. de Groot and Mrs N. van de Berg, Reinier de Graaf Hospital, Delft; Mrs M. van Mierlo and Mrs M. Pelk, Jeroen Bosch Hospital, location GZG, Den Bosch; Mrs M. van Noort, ‘t Lange Land Hospital, Zoetermeer; Mrs M. Poessée and Mrs B. Roos, Medical Center Rijnmond-Zuid, location Zuider, Rotterdam; Mr M. Smits, Bernhoven Hospital, location Oss; Mrs J. van Meel and Mrs.T. Horsman, Oosterschelde Hospital, Goes; Mrs I. Houben and Mr F. v. Ulft, VieCuri Medical Centre Noord-Limburg, location Venlo; Mrs M. van der Rakt and Mrs M. Thijssen, University Hospital Groningen, Groningen; Mr R. Dukelo, Jeroen Bosch Hospital, location Carolus, Den Bosch; Mrs. C. Tiedemann, Groene Hart Hospital, Gouda; Mrs M. Nannini, St. Antonius Hospital, Nieuwegein. We thank Mrs M. Ridderhof-van’t Veer, infection control practitioner of the CHIPS-project, for supporting the data collection on surgical prophylaxis in serveral hospitals.

This study was supported by The Netherlands Organisation for Health Research and Development (ZonMw).


    Footnotes
 
* Corresponding author. Tel: +31–24–3616499; Fax: +31–24–3541734; E-mail: M.vanKasteren{at}aig.umcn.nl Back


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 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
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