Monitoring the one year postoperative infection rate after primary total hip replacement.
OBJECTIVE
Infection of a total hip replacement is potentially a devastating complication. Statistical process control methods have been generating interest as a means of improving the quality of healthcare, and we report our experience with the implementation of such a method to monitor the one year infection rate after primary total hip replacement.


METHODS
Infection was defined as the growth of the same organism in cultures of at least two aspirates or intra-operative specimens, or growth of one pathogen in a patient with local signs of infection such as erythema, abscess or draining sinus tract. The cumulative summation test (CUSUM test) was used to continuously monitor the one year postoperative infection rate. The target performance was 0.5% and the test was set to detect twice that rate.


RESULTS
Over the three year study period, 2006 primary total hip replacements were performed. Infection developed within one year after surgery in eight (0.4%) hips. The CUSUM test generated no alarms during the study period, indicating that there was no evidence that the process was out of control.


CONCLUSIONS
The one year infection rate after primary total hip replacement was in control. The CUSUM test is a useful method to continuously ensure that performance is maintained at an adequate level.
Departement de Biostatistique et Informatique Medicale, Hopital Saint-Louis, AP-HP, Paris, France. djmbiau@yahoo.fr
David J
DJ
Biau
Philippe
P
Leclerc
Simon
S
Marmor
Valerie
V
Zeller
Wilfrid
W
Graff
Luc
L
Lhotellier
Philippe
P
Leonard
Patrick
P
Mamoudy
D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000592:standards*; D001424:Bacterial Infections / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D013530:Surgical Wound Infection / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D017211:Treatment Failure