Assessment of operating room airflow using air particle counts and direct observation of door openings

Automated traffic monitoring of neurosurgical operating room

BACKGROUND

Operating room (OR) traffic disrupts airflow and increases particle count, which predisposes patients to surgical site infections, particularly in longer surgeries with hardware placement. The aim of this study is to evaluate the rate of traffic during neurosurgical procedures, as well as reasons for and perceptions of OR traffic.

METHODS

This is a single-center, multimethod study monitoring neurosurgical OR traffic through direct observation, automated monitoring, and interviews. Traffic was observed between the skin incision and closure. Personal interviews with OR teams including surgeons, anesthesia, and nurses were conducted to evaluate their perceptions of the frequency of OR traffic and reasons for OR traffic.

RESULTS

Direct observation reported OR door opening an average of 18 times, with 20 people entering or exiting per hour. The exact reason for traffic was not verified in all traffic cases and was able to be confirmed in only a third of the cases. Automated monitoring resulted in an average of 31 people entering or exiting the OR per hour. The procedure length was significantly associated with the number of people entering or exiting the OR per hour (P < .0001). Interviews highlighted that OR teams reported traffic to be significantly lower than observed and automated monitoring results, with approximately <6 people entering or exiting per hour.

CONCLUSIONS

OR traffic is higher than staff expected, and updated processes are required to reduce the number of times the OR door opens. Implementing automated observation of OR traffic could reduce the OR traffic and the risk for surgical site infection.

Preoperative antibiotics reduce early surgical site infections after orthopaedic implant removal: a propensity-matched cohort study

BACKGROUND

Implant removal in orthopaedics after fracture consolidation is a very common procedure but is still associated with a high rate of surgical site infection (SSI). Antibiotic prophylaxis is not recommended but advocated by some.

AIM

To assess the efficacy of antibiotic prophylaxis in the prevention of early SSI following orthopaedic implant removal.

METHODS

A monocentric retrospective cohort study was conducted. Patients who underwent orthopaedic implant removal procedures performed from 2016 to 2021 were included. A 1:1 propensity score matching function was used to create a cohort with matched baseline characteristics and associated risk factors for SSI. Inter-cohort comparison of the occurrence of SSI (superficial or deep) and revision surgery for SSI, after propensity score matching, was performed using the odds ratio to determine the effect of preoperative antibiotic prophylaxis.

FINDINGS

In total, 965 distinct surgical procedures were included. Of these, 69 (7.15%) had an SSI, 24 (35.7%) of which required surgical revision; 214 procedures (22.18%) were performed under preoperative antibiotic prophylaxis. The propensity-matched cohort consisted of 396 procedures (198 with and without antibiotic prophylaxis). The SSI rates were 11.11% and 3.03%, respectively, in the control and antibiotic prophylaxis groups (odds ratio: 0.25; 95% confidence interval: 0.099; 0.63; P = 0.011). No difference was found for revision surgery.

CONCLUSION

Preoperative administration of antibiotic prophylaxis considerably reduces the risk of SSI during the removal of an orthopaedic implant without increasing the risk of side-effects.

Larger operating rooms have better air quality than smaller rooms in primary total knee arthroplasty

INTRODUCTION

Operating room air quality can be affected by several factors including temperature, humidity, and airborne particle burden. Our study examines the role of operating room (OR) size on air quality and airborne particle (ABP) count in primary total knee arthroplasty (TKA).

MATERIALS AND METHODS

We analyzed all primary, elective TKAs performed within two ORs measuring 278 sq ft. (small) and 501 sq ft. (large) at a single academic institution in the United States from April 2019 to June 2020. Intraoperative measurements of temperature, humidity, and ABP count were recorded. p values were calculated using t test for continuous variables and chi-square for categorical values.

RESULTS

91 primary TKA cases were included in the study, with 21 (23.1%) in the small OR and 70 (76.9%) in the large OR. Between-groups comparisons revealed significant differences in relative humidity (small OR 38.5% ± 7.24% vs. large OR 44.4% ± 8.01%, p = 0.002). Significant percent decreases in ABP rates for particles measuring 2.5 μm (- 43.9%, p = 0.007) and 5.0 μm (- 69.0%, p = 0.0024) were found in the large OR. Total time spent in the OR was not significantly different between the two groups (small OR 153.09 ± 22.3 vs. large OR 173 ± 44.6, p = 0.05).

CONCLUSIONS

Although total time spent in the room did not differ between the large and small OR, there were significant differences in humidity and ABP rates for particles measuring 2.5 μm and 5.0 μm, suggesting the filtration system encounters less particle burden in larger rooms. Larger studies are required to determine the impact this may have on OR sterility and infection rates.

Risk Influence of Some Environmental and Behavioral Factors on Air Contamination in the Operating Room: An Experimental Study

Air contamination in operating rooms (ORs) depends on the conditions of the room and on activities therein performed. Methodologies of air quality assessment in ORs are often inadequately described in the scientific literature, and the time required for a change in status in air quality is never taken into account. The purpose of this study was to determine the influence of the state and the presence of human operators on air quality by implementing a precise measurement protocol that also took into account the time required for changes in the room to affect air pollution. As the main indicators of air pollution, bacterial load and concentration of airborne dust were measured. The results showed that: the use of surgical masks by operators in the OR did not significantly affect bacterial load within a distance of 2 m; keeping OR doors open did not induce a significant increase in bacterial load and of 5 μm particles while 10 μm particles concentration was positively affected; and air pollution measured with open doors was not significantly different from that due to the presence of two staff members, whether or not they were wearing masks. The results clarified the role of some factors on air pollution in ORs.

Distractions in the operating room: a survey of the healthcare team

BACKGROUND

Distractions during surgical procedures are associated with team inefficiency and medical error. Little is published about the healthcare provider's perception of distraction and its adverse impact in the operating room. We aim to explore the perception of the operating room team on multiple distractions during surgical procedures.

METHODS

A 26-question survey was administered to surgeons, anesthesia team members, nurses, and scrub technicians at our institution. Respondents were asked to identify and rank multiple distractions and indicate how each distraction might affect the flow of surgery.

RESULTS

There was 160 responders for a response rate of 19.18% (160/834), of which 71 (44.1%) male and 82 (50.9%) female, 48 (29.8%) surgeons, 59 (36.6%) anesthesiologists, Certified Registered Nurse Anesthetists (CRNA), and 53 (32.9%) OR nurses and scrub technicians. Responders were classified into a junior group (< 10 years of experience) and a senior group (≥ 10 years). Auditory distraction followed by equipment were the most distracting factors in the operating room. All potential auditory distractions in this survey were associated with higher percentage of certain level of negative impact on the flow of surgery except for music. The top 5 distractors belonged to equipment and environment categories. Phone calls/ pagers/ beepers and case relevant communications were consistently among the top 5 most common distractors. Case relevant communications, music, teaching, and consultation were the top 4 most perceived positive impact on the flow of surgery. Distractors with higher levels of "bothersome" rating appeared to associate with a higher level of perceived negative impact on the flow of surgery. Vision was the least distracting factor and appeared to cause minimal positive impact on the flow of surgery.

CONCLUSIONS

To our knowledge, this is the first survey studying perception of surgery, anesthesia, and OR staff on various distractions in the operating room. Fewer unnecessary distractions might improve the flow of surgery, improve OR teamwork, and potentially improve patient outcomes.

Current and potential approaches on assessing airflow and particle dispersion in healthcare facilities: a systematic review

An indoor environment in a hospital building requires a high indoor air quality (IAQ) to overcome patients' risks of getting wound infections without interrupting the recovery process. However, several problems arose in obtaining a satisfactory IAQ, such as poor ventilation design strategies, insufficient air exchange, improper medical equipment placement and high door opening frequency. This paper presents an overview of various methods used for assessing the IAQ in hospital facilities, especially in an operating room, isolation room, anteroom, postoperative room, inpatient room and dentistry room. This review shows that both experimental and numerical methods demonstrated their advantages in the IAQ assessment. It was revealed that both airflow and particle tracking models could result in different particle dispersion predictions. The model selection should depend on the compatibility of the simulated result with the experimental measurement data. The primary and secondary forces affecting the characteristics of particle dispersion were also discussed in detail. The main contributing forces to the trajectory characteristics of a particle could be attributed to the gravitational force and drag force regardless of particle size. Meanwhile, the additional forces could be considered when there involves temperature gradient, intense light source, submicron particle, etc. The particle size concerned in a healthcare facility should be less than 20 μm as this particle size range showed a closer relationship with the virus load and a higher tendency to remain airborne. Also, further research opportunities that reflect a more realistic approach and improvement in the current assessment approach were proposed.

Comparative Incidence of Periocular Surgical Site Infections with Increased Surgical Mask Use during the COVID-19 Pandemic

PURPOSE

To evaluate the effect of surgical mask use on infection rates for office-based periocular surgeries during the pandemic.

METHODS

An Institutional Review Board-approved retrospective review of medical records identified patients who had an office-based oculofacial plastic surgery procedure during the pandemic between March and December 2020. Statistical analysis was used to compare this group to patients that underwent procedures between March and December 2019, prior to the pandemic when neither surgeon nor patient wore a surgical mask.

RESULTS

The study consisted of 680 patients. Thirty-one different types of procedures were encountered. The incidence of infections in 2020 compared to 2019 was not statistically significant (1.12% (n = 3) versus 1.21% (n = 5), p = 1). All patients with infections were treated with oral antibiotics and improved without long-term complications.

CONCLUSIONS

Periocular surgical site infections are uncommon, and the wearing of surgical masks by patient and surgeon during our office-based oculofacial procedures did not change the incidence of SSIs.

Do Ultraviolet Air Disinfection Units Reduce Contamination by Particulates in Total Knee Replacement Procedures?

BACKGROUND

Prosthetic joint infections have become the leading cause of joint replacement failure. The primary sources of contamination are skin flora and bacteria from airborne particles. Portable ultraviolet air disinfection units are used in the Operating Room (OR) to prevent contamination from airborne particles; however, their effectiveness is not proven. The purpose of this study was to compare the rate of contamination of sites with and without Ultraviolet (UV) air disinfection units during active surgeries.

METHODS

Sedimentation rates of viable particles were measured during 40 primary TKA procedures. Half of the procedures were performed with ultraviolet air disinfection units. Air-borne particles were collected on nitrocellulose membranes at 5 locations within the OR. After incubation, all microbial colonies were counted and the sedimentation rates were reported in CFUs/m²/hr. 10 additional trials were performed in an empty OR with no staff present.

RESULTS

The average contamination rate of all sites was 22 ± 1.1 CFUs/m²/hr in the empty OR vs. 21.3 ± 4.6 CFUs/m²/hr with UV units and 20.3 ± 4.9 CFUs/m²/hr without (P = .03, P = .03, P = .964). Viable contaminates were found in the sterile field in 25% of UV cases vs 45% non-UV. These differences were not statistically significant. There were differences found however, according to the number of staff in the room (6 vs 7 staff: P = .036, 6 vs 8 staff: P = .004).

CONCLUSION

There was no statistical difference in contamination rate with the usage or non-usage of UV units. These 40 cases shows that the largest variables affecting the contamination rate were the number of staff present and size of the OR.

Systematic study on the relationship between particulate matter and microbial counts in hospital operating rooms

In this study, a systematic procedure for establishing the relationship between particulate matter (PM) and microbial counts in four operating rooms (ORs) was developed. The ORs are located in a private hospital on the western coast of Peninsular Malaysia. The objective of developing the systematic procedure is to ensure that the correlation between the PMs and microbial counts are valid. Each of the procedures is conducted based on the ISO, IEST, and NEBB standards. The procedures involved verifying the operating parameters are air change rate, room differential pressure, relative humidity, and air temperature. Upon verifying that the OR parameters are in the recommended operating range, the measurements of the PMs and sampling of the microbes were conducted. The TSI 9510-02 particle counter was used to measure three different sizes of PMs: PM 0.5, PM 5, and PM 10. The MAS-100ECO air sampler was used to quantify the microbial counts. The present study confirms that PM 0.5 does not have an apparent positive correlation with the microbial count. However, the evident correlation of 7% and 15% were identified for both PM 5 and PM 10, respectively. Therefore, it is suggested that frequent monitoring of both PM 5 and PM 10 should be practised in an OR before each surgical procedure. This correlation approach could provide an instantaneous estimation of the microbial counts present in the OR.

High Number of Door Openings Increases the Bacterial Load of the Operating Room

Background: Operating room (OR) traffic and door openings have emerged as potential modifiable risk factors for the development of surgical site infections. Methods: This study compared the microbial load of a Control OR without traffic versus a Simulated OR with the traffic in a typical orthopedic surgery case. Air particle counts and colony forming units (CFUs) were measured. A novel iOS app was developed to provide real-time door counts. Results: There were 1,862 particles >5.0 mcm in the Simulated OR compared with 56 in the Control OR. The CFUs from plates in the Simulated OR ranged from 4-22 (on brain heart infusion [BHI] agar), 2-266 (on mannitol salt agar [MSA]), and 1-19 (on Pseudomonas isolation agar [PIA]), while all plates in the Control OR grew 0-1 CFUs. Conclusions: High number of door openings leads to more airborne bacteria in the OR and viable bacterial on OR surfaces. The increased bacterial load throughout the OR was independent of distance from the door.

The effect of intraoperative distractions on severe technical events in laparoscopic bariatric surgery

BACKGROUND

Given the complexity of the operating room (OR), it is unsurprising that surgeons frequently feel distracted while performing operative tasks. However, this relationship is not well studied in live surgeries. The objective of this study is to investigate the relationship between intraoperative distractions and technical events using surgical data.

METHODS

Roux-en-Y gastric bypass operation data from three tertiary care hospitals in Toronto, Canada were collected prospectively between 2017 and 2019 by a comprehensive operative capture platform (OR Black Box) and analyzed retrospectively. Time-synchronized audiovisual recordings of the OR and laparoscopic videos of the operation were collected, along with clinical data from the electronic health record. Video data was labeled for technical data, non-technical data, and distractions by trained coders. Procedural steps were categorized based on criticality. The relationship between severe technical events (case having 0 or 1 events vs. 2 or more) and the rate of distractions (machine alarms, external communications, people entering/exiting) in critical procedural steps was assessed through logistic regression, adjusting for team factors (surgeons' technical skills, nurse changeovers).

RESULTS

60 Roux-en-Y cases were analyzed. Average case duration was 83.2 min (SD = 21.97). Distractions occurred 47.6 times/h (SD = 20.3), with most frequent distraction being machine alarms (4.45/10 min, SD = 2.88). For unadjusted analysis, alarms (OR = 1.29, 95% CI 1.05-1.66) and surgeon's technical skills (OR = 0.65, 95% CI 0.43-0.93) were found to be correlated with severe technical events. After adjusting for team factors, alarms were found to be positively related with the presence of severe technical events (OR = 1.58, 95% CI 1.18-2.33) during high-criticality procedural steps.

CONCLUSIONS

This study showed a significant association between intraoperative distractions, in particular machine alarms, and severe technical events during high-criticality procedural steps. Further investigation will assess the temporal relationship between distractions and technical events and assess mitigation strategies to create a safer surgical environment.

Operating Room Traffic in Total Joint Arthroplasty: One Simple Measure Toward Solving a Complex Problem

Periprosthetic joint infection remains a devastating complication of total joint arthroplasty (TJA). The literature suggests that unnecessary operating room (OR) traffic increases the risk of surgical site infection by increasing bacterial load in the OR. We attempted to determine whether the posting of “restricted access” signs on the outside and inside of OR doors during primary TJA procedures would result in a reduction of OR door openings.

Frequent Door Openings During Cardiac Surgery Are Associated With Increased Risk for Surgical Site Infection: A Prospective Observational Study

BACKGROUND

Preliminary studies that analyzed surrogate markers have suggested that operating room (OR) door openings may be a risk factor for surgical site infection (SSI). We therefore aimed to estimate the effect of OR door openings on SSI risk in patients undergoing cardiac surgery.

METHODS

This prospective, observational study involved consecutive patients undergoing cardiac surgery in 2 prespecified ORs equipped with automatic door-counting devices from June 2016 to October 2017. Occurrence of an SSI within 30 days after cardiac surgery was our primary outcome measure. Respective outcome data were obtained from a national SSI surveillance cohort. We analyzed the relationship between mean OR door opening frequencies and SSI risk by use of uni- and multivariable Cox regression models.

RESULTS

A total of 301 594 OR door openings were recorded during the study period, with 87 676 eligible door openings being logged between incision and skin closure. There were 688 patients included in the study, of whom 24 (3.5%) developed an SSI within 30 days after surgery. In uni- and multivariable analysis, an increased mean door opening frequency during cardiac surgery was associated with higher risk for consecutive SSI (adjusted hazard ratio per 5-unit increment, 1.49; 95% confidence interval, 1.11-2.00; P = .008). The observed effect was driven by internal OR door openings toward the clean instrument preparation room.

CONCLUSIONS

Frequent door openings during cardiac surgery were independently associated with an increased risk for SSI. This finding warrants further study to establish a potentially causal relationship between OR door openings and the occurrence of SSI.

Intraoperative and Postoperative Infection Prevention

Implementation of strategies for prevention of surgical site infection and periprosthetic joint infection is gaining further attention. We provide an overview of the pertinent evidence-based guidelines for infection prevention from the World Health Organization, the Centers for Disease Control and Prevention, and the second International Consensus Meeting on Musculoskeletal Infection. Future work is needed to ascertain clinical efficacy, optimal combinations, and the cost-effectiveness of certain measures.

In-Room Ultraviolet Air Filtration Units Reduce Airborne Particles During Total Joint Arthroplasty

Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet-C (C-UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C-UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony-forming units (CFUs). Fifty primary TJA cases were performed in a positive-pressure OR; 25 cases with the C-UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m³ between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C-UVC group had significantly lower TPC (2.6 × 10⁶ vs. 4.7 × 10⁶ particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C-UVC group (10.9 CFU/m³ vs. 13.7 CFU/m³ , p = 0.163). Multivariate analysis identified C-UVC filtration as a significant predictor of decreased TPC (β = -0.44, p = 0.002) and VPC (β = -0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C-UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non-significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C-UVC filtration units on surgical-site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431-437, 2020.

Hospital infection control and behaviour of operating room staff

OBJECTIVES

Surgical site infections (SSIs) are a frequent complication of surgical procedures and one of the most common forms of hospital acquired infection (HAI). National/international guidelines and recommendations have been issued for prevention. The objective of this study was to observe the behaviour of healthcare workers engaged in surgical procedures and hence assess compliance with SSI guidelines.

METHODS

An observational descriptive study was conducted at a University hospital in southern Italy. A specifically designed form was used to record the actions of the surgical team during randomly selected surgical operations. Observations comprised the use of surgical attire, the frequency of doors opening and the number of staff in the operating room.

RESULTS

A total of 308 operating room personnel was observed during 402 surgical procedures: 127 surgeons (41%), 39 anaesthesiologists (13%), 62 nurses (20%) and 80 students in training (26%). 96% of the surgical team wore scrubs, 93% of health workers wore a mask and of these 78% wore it correctly in order to completely cover the nose, mouth and beard (when present), 99% wore a cap (only in 48% was the hair completely covered), 50% of the operators wore gloves, 95% wore shoes dedicated to the operating theater and 23% also wore shoe covers, 56% wore gowns, and 22% had eye protection. Furthermore, the average number of health personnel in the operating theater was 8, the doors remained closed in 261 (65%) surgical operations.

CONCLUSION

As the results indicated a low adherence to international guidelines among the personnel, it is suggested that training courses should be provided to increase staff awareness on prevention and management of HAI.

Influence of a visible-light continuous environmental disinfection system on microbial contamination and surgical site infections in an orthopedic operating room

BACKGROUND

A growing body of research has demonstrated that manual cleaning and disinfection of the operating room (OR) is suboptimal. Residual environmental contamination may pose an infection risk to the surgical wound. This study evaluates the impact of a visible-light continuous environmental disinfection (CED) system on microbial surface contamination and surgical site infections (SSI) in an OR.

METHODS

Samples from 25 surfaces within 2 contiguous ORs sharing an air supply were obtained after manual cleaning on multiple days before and after a visible-light CED system installation in 1 of the ORs. Samples were incubated and enumerated as total colony-forming units. SSIs in both ORs, and a distant OR, were tracked for 1 year prior to and 1 year after the visible-light CED system installation.

RESULTS

There was an 81% (P = .017) and 49% (P = .015) reduction in total colony-forming units after the visible-light CED system installation in the OR in which the system was installed, and in the contiguous OR, respectively. In the OR with the visible-light CED system, SSIs decreased from 1.4% in the year prior to installation to 0.4% following installation (P = .029).

CONCLUSIONS

A visible-light CED system, used in conjunction with manual cleaning, resulted in significant reductions in both microbial surface contamination and SSIs in the OR.

An exploration on the relationship between traffic flow and the rate of surgical site infections: A literature review

Surgical site infections are the second most frequent type of health-care associated infections in Europe and America. Public Health England's data on 139,691 operations at 209 hospitals reported 1,635 surgical site infections between April 2012 and March 2017. Patients with a surgical site infection are twice as likely to die, five times more likely to be readmitted after discharge and are likely to have a prolonged hospitalization. Therefore, it is still a significant issue that professionals need to help reduce. This literature review looks at ventilation within theatres and how traffic flow can affect the air flow and if it can increase the incidence rates of surgical site infections. Recommendations of strategies are made to help reduce traffic flow within operating theatres.