What’s New in the Patient Safety World

December 2017

A Fix for OR Foot Traffic?



In several of our columns we’ve warned that long surgical duration has the potential to increase surgery-related infections and that excessive OR traffic and opening of OR doors is likely a major factor. In our March 10, 2009 Patient Safety Tip of the Week “Prolonged Surgical Duration and Time Awareness” we noted a study (Lynch 2009) that suggested increased foot traffic may be factor related to prolonged procedures that increases the likelihood of surgical site infections. Then in our January 2010 What's New in the Patient Safety World column “Operative Duration and Infection” we discussed another study (Proctor et al 2010) that looked at a large database of general surgical procedures and demonstrated a linear relationship between duration of surgery and infectious complications. This relationship persisted even after adjustment for a variety of other risk factors for perioperative infections. The unadjusted infectious complication rate increased by 2.5% per half hour. Hospital length of stay (LOS) also increased geometrically by 6% per half hour. We again speculated that increased foot traffic may be another factor related to prolonged procedures that increases the likelihood of surgical site infections as suggested by Lynch et al. And our December 30, 2014 Patient Safety Tip of the Week “Data Accumulates on Impact of Long Surgical Duration” cited several other studies in which surgical infections were one of several complications related to prolonged surgery.


Then in our November 24, 2015 Patient Safety Tip of the Week “Door Opening and Foot Traffic in the OR” we discussed a study from Johns Hopkins that formally studied how often OR doors are opened during joint arthroplasty surgeries and the impact on OR air flow (Mears 2015). The researchers measured how often and for how long OR doors were opened during 191 hip and knee arthroplasty procedures. They also measured air pressures in the OR and adjacent corridors. They found that, on average, OR doors were open 9.5 minutes per case and the average time between door openings was 2.5 minutes. As you’d expect the number and duration of door openings correlated with the length of surgery. In 77 of the 191 cases positive pressure within the OR was defeated. The implications are obvious. While they found only one surgical infection in the 191 cases, the effects of the door opening on OR pressure and air flow theoretically would predispose to surgical infections. OR’s have positive pressure to avoid flow of air and airborne pathogens from nonsterile adjacent areas.


Finally, our July 26, 2016 Patient Safety Tip of the WeekConfirmed: Keep Your OR Doors Closed” highlighted a study that actually demonstrated that a program to reduce unnecessary door openings may reduce surgery-related infections (Camus 2016). A Canadian hospital did a manual count of door openings during total joint replacement operations and revision procedures. They counted between 42 and 70 door openings per operation from incision time to joint capsule closure time. Operations averaged 75 minutes. Reasons for entering and exiting the OR during operations included retrieving charts, instruments, or equipment, and taking a break. Next their CUSP (Comprehensive Unit-Based Program) team brainstormed and came up with key changes, including stopping all traffic in and out of the OR between total joint capsule opening and closure, communicating by phone, and increasing the use of templates to identify implant size prior to each operation. They also put a sign on the OR door reminding staff to minimize traffic and asking them to record why they are entering the OR during an operation. Subsequent traffic audits taken every six months indicated an amazing reduction in OR traffic from between 42 and 70 door openings to 3.2 door openings per case. They felt this intervention may have contributed to a decrease in orthopedic SSIs from 2.8 percent to 2.1 percent.


Now yet another study looked at the impact of an audible alarm on reducing OR foot traffic during total joint arthroplasties (Eskildsen 2017). Researchers placed an audible alarm on the substerile operating room door that sounded continuously when the door was ajar. This resulted in a significant difference in the overall mean door openings per minute between the period with no alarm and with an alarm. Prior to the door alarm, the substerile door was opened a mean of 88.12 times per case, or 0.53 times per minute. After the door alarm was installed, door openings decreased to a mean of 69.46 times per surgery, or 0.42 times per minute. However, this effect slowly decreased over the time of the intervention.


The percentage of time the door was left ajar per case also decreased significantly with the alarm. Prior to the intervention the door remained open for a mean of 14.45 minutes per case, or 8.65% of overall surgical time. After the door alarm was installed the mean duration of time that the door remained open decreased to 10.81 minutes per surgery, or 6.63% of the overall surgical time.


Unfortunately, the study was not large enough to determine whether the reduced door opening had an impact on surgical infection rates. But the findings certainly suggest that this may be one way to reduce such infections.


So while the idea of using an alarm or our prior suggestion of using an “On the Air” sign similar to that used in television or radio studios may help alert staff to the fact that excess foot traffic into and out of the OR are undesirable, neither is a forcing function. Forcing functions are much better interventions. One quasi-forcing function we’ve suggested is keeping a log where staff are required to log in every time they leave and enter the OR for each case, similar to what was done in the Canadian study (Camus 2016).  Of course, there will be blowback from many of your staff that this might be time consuming. It need not be. How many of you have an electronic device like an Amazon Echo or a Google Home Assistant and say something like “Alexa, add paper towels to my grocery list.”? Alexa creates a grocery list and adds paper towels to it. You could do the same with such a device in your substerile OR area and, when the OR door alarm sounds, require the person entering the OR to say something like “Alexa, this is surgical tech Yvonne Jones entering the OR with new equipment” and Alexa could add the name of the staff member and the reason to the log created when the case began. Voila! It took years before we learned about barcoding from our supermarkets and applied it to healthcare. It’s time we take a lesson from our hi-tech kitchens!


And, of course, the potential benefit of such a system is not just on surgical infections. We’d anticipate that the number of distractions and interruptions would likely decrease with decreased movement in and out of the OR. And analysis of the log entries should help identify ways to improve OR efficiency. For example, the log entries might identify the need for a certain supply or piece of equipment to be present prior to the cases. So we’d suggest you make review of the log part of your postop debriefing. You are doing debriefings after every case, aren’t you?




Our prior columns focusing on surgical OR foot traffic and door opening:







Lynch RJ, Englesbe MJ, Sturm L, et al. Measurement of Foot Traffic in the Operating Room: Implications for Infection Control. American Journal of Medical Quality 2009; 24: 45-52




Procter LD, Davenport DL, Bernard AC, Zwischenberger JB. General Surgical Operative Duration Is Associated with Increased Risk-Adjusted Infectious Complication Rates and Length of Hospital Stay, Journal of the Amercican College of Surgeons 2010; 210: 60-65




Mears SC, Blanding R, Belkoff SM. Door Opening Affects Operating Room Pressure During Joint Arthroplasty. Orthopedics 2015; 38(11): e991-e994




Camus S. Operating Room Traffic Monitoring Improves Patient Safety. Abstract session presentation at the 2016 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP®) Conference. July 18, 2016 as reported in ACS (American College of Surgeons). Minimizing Operating Room Traffic May Improve Patient Safety by Lowering Rates of Surgical Site Infections. ACS Press Release July 18, 2016




Eskildsen SM, Moskal PT, Laux J, Del Gaizo DJ. The Effect of a Door Alarm on Operating Room Traffic During Total Joint Arthroplasty. Orthopedics 2017; 40(6): e1081-e1085






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