Major article
Traffic flow in the operating room: An explorative and descriptive study on air quality during orthopedic trauma implant surgery

https://doi.org/10.1016/j.ajic.2011.09.015Get rights and content

Background

Understanding the protective potential of operating room (OR) ventilation under different conditions is crucial to optimizing the surgical environment. This study investigated the air quality, expressed as colony-forming units (CFU)/m3, during orthopedic trauma surgery in a displacement-ventilated OR; explored how traffic flow and the number of persons present in the OR affects the air contamination rate in the vicinity of surgical wounds; and identified reasons for door openings in the OR.

Methods

Data collection, consisting of active air sampling and observations, was performed during 30 orthopedic procedures.

Results

In 52 of the 91 air samples collected (57%), the CFU/m3 values exceeded the recommended level of <10 CFU/m3. In addition, the data showed a strongly positive correlation between the total CFU/m3 per operation and total traffic flow per operation (r = 0.74; P = .001; n = 24), after controlling for duration of surgery. A weaker, yet still positive correlation between CFU/m3 and the number of persons present in the OR (r = 0.22; P = .04; n = 82) was also found. Traffic flow, number of persons present, and duration of surgery explained 68% of the variance in total CFU/m3 (P = .001).

Conclusions

Traffic flow has a strong negative impact on the OR environment. The results of this study support interventions aimed at preventing surgical site infections by reducing traffic flow in the OR.

Section snippets

Setting

The study was performed at a Swedish university hospital that performs approximately 9,000 surgical procedures annually. Data was collected in 3 parallel ORs of equal size (39 m2), each equipped with an upward air-displacement system supplying cool air (2-3°C below room temperature) above the floor in each of the 4 corners of the room. By thermal convection, the air is evacuated via 4 exhaust fans installed in the ceiling. Each OR is supposed to be maintained at positive air pressure by

Results

Air sampling was performed during 30 orthopedic operations in a total of 120 air sampling intervals. The distributions of surgical procedures were 73 plates and screws (60.8%), 26 intramedullary nails (21.7%), and 21 hemiarthroplasties (17.5%). The variations in CFU/m3 values were found between operations rather than during operations (P = .001). In 52 of 91 samples, the CFU/m3 values exceeded the recommended level of <10 CFU/m3. In 14 of 24 operations, the mean values exceeded 10 CFU/m3; in 5

Discussion

In orthopedic surgery, large-scale efforts and research activities have focused on infection control, mainly in relation to elective primary joint replacement surgery. The findings of the present study show that the recommended limit of >10 CFU/m3 was exceeded in 57% of the samples analyzed. Patients with orthopedic trauma carry an extra burden of preoperative soft tissue and skeletal damage, and have minimal opportunities to be optimized in relation to comorbidities that are known to be major

Conclusion

This study has clearly linked elevated airborne bacterial counts in the surgical area to door openings in conventionally ventilated ORs, thereby providing the scientific evidence needed to initiate interventions aimed at preventing SSI by reducing traffic flow in the OR. In addition, analyzing the reasons for door openings seems to be of great importance to the success of any intervention implemented.

Acknowledgment

The authors thank the OR staff and orthopedic surgeons for their participation in this study, and L.O. Persson for statistical advice.

References (48)

  • A. Tammelin et al.

    Source and route of methicillin-resistant Staphylococcus epidermidis transmitted to the surgical wound during cardio-thoracic surgery: possibility of preventing wound contamination by use of special scrub suits

    J Hosp Infect

    (2001)
  • W. Whyte

    The role of clothing and drapes in the operating room

    J Hosp Infect

    (1988)
  • D.J. Wilson et al.

    Gravity-driven counterflow through an open door in a sealed room

    Build Environ

    (1990)
  • S. Scaltriti et al.

    Risk factors for particulate and microbial contamination of air in operating theatres

    J Hosp Infect

    (2007)
  • D.A. Campbell et al.

    Surgical site infection prevention: the importance of operative duration and blood transfusion. Results of the first American College of Surgeons National Surgical Quality Improvement Program Best Practices Initiative

    J Am Coll Surg

    (2008)
  • B.F. Friberg et al.

    Inefficiency of upward-displacement operating theatre ventilation

    J Hosp Infect

    (1996)
  • K.J. Bozic et al.

    The impact of infection after total hip arthroplasty on hospital and surgeon resource utilization

    J Bone Joint Surg Am

    (2005)
  • V. Monge Jodra et al.

    Excess length of stay attributable to surgical site infection following hip replacement: a nested case-control study

    Infect Control Hosp Epidemiol

    (2006)
  • C. Zhan et al.

    Incidence and short-term outcomes of primary and revision hip replacement in the United States

    J Bone Joint Surg Am

    (2007)
  • D. Lindstrom et al.

    Effects of a perioperative smoking cessation intervention on postoperative complications: a randomized trial

    Ann Surg

    (2008)
  • T. Thomsen et al.

    Effect of preoperative smoking cessation interventions on postoperative complications and smoking cessation

    Br J Surg

    (2009)
  • A.F. Pull ter Gunne et al.

    Incidence, prevalence, and analysis of risk factors for surgical site infection following adult spinal surgery

    Spine (Phila Pa 1976)

    (2009)
  • B.E. Bierbaum et al.

    An analysis of blood management in patients having a total hip or knee arthroplasty

    J Bone Joint Surg Am

    (1999)
  • D.H. Culver et al.

    Surgical wound infection rates by wound class, operative procedure, and patient risk index: National Nosocomial Infections Surveillance System

    Am J Med

    (1991)
  • Cited by (0)

    Author contributions: A.E.A., I.B., B.E., J.K., and K.N. designed the study; A.E.A. performed data collection and coordination; A.E.A. and I.B. analyzed data; and A.E.A., I.B., B.E., J.K., and K.N. wrote the manuscript.

    Conflict of interest: None to report.

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