A threshold of 100 or more colony-forming units on the anesthesia machine predicts bacterial pathogen detection: a retrospective laboratory-based analysis.

PURPOSE: Preventing the spread of pathogens in the anesthesia work area reduces surgical site infections. Improved cleaning reduces the percentage of anesthesia machine samples with ≥ 100 colony-forming units (CFU) per surface area sampled. Targeting a threshold of < 100 CFU when cleaning anesthesia machines may be associated with a lower prevalence of bacterial pathogens. We hypothesized that anesthesia work area reservoir samples returning < 100 CFU would have a low (< 5%) prevalence of pathogens. METHODS: In this retrospective cohort study of bacterial count data from nine hospitals, obtained between 2017 and 2022, anesthesia attending and assistants' hands, patient skin sites (nares, axilla, and groin), and anesthesia machine (adjustable pressure-limiting valve and agent dials) reservoirs were sampled at case start and at case end. The patient intravenous stopcock set was sampled at case end. The isolation of ≥ 1 CFU of Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Enterococcus, vancomycin-resistant Enterococcus, gram-negative (i.e., Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter spp.) or coagulase-negative Staphylococcus was compared for reservoir samples returning ≥ 100 CFU vs those returning < 100 CFU. RESULTS: Bacterial pathogens were isolated from 24% (7,601/31,783) of reservoir samples, 93% (98/105) of operating rooms, and 83% (2,170/2,616) of cases. The ratio of total pathogen isolates to total CFU was < 0.0003%. Anesthesia machine reservoirs returned ≥ 100 CFU for 44% (2,262/5,150) of cases. Twenty-three percent of samples returning ≥ 100 CFU were positive for ≥ 1 bacterial pathogen (521/2,262; 99% lower confidence limit, 22%) vs 3% of samples returning < 100 CFU (96/2,888; 99% upper limit, 4%). CONCLUSIONS: Anesthesia machine reservoir samples returning < 100 CFU were associated with negligible pathogen detection. This threshold can be used for assessment of terminal, routine, and between-case cleaning of the anesthesia machine and equipment. Such feedback may be useful because the 44% prevalence of ≥ 100 CFU was comparable to the 46% (25/54) reported earlier from an unrelated hospital.

RéSUMé: OBJECTIF: La prévention de la propagation des agents pathogènes dans la zone de travail de l'anesthésie réduit les infections du site opératoire. L'amélioration du nettoyage réduit le pourcentage d'échantillons de l'appareil d'anesthésie présentant ≥ 100 unités de formation de colonie (UFC) par surface échantillonnée. Le fait de cibler un seuil < 100 UFC lors du nettoyage des appareils d'anesthésie pourrait être associé à une prévalence plus faible d'agents pathogènes bactériens. Nous avons émis l'hypothèse que les échantillons des réservoirs de la zone de travail d'anesthésie < 100 UFC résulteraient en une faible prévalence (< 5 %) d'agents pathogènes. MéTHODE: Dans cette étude de cohorte rétrospective des données de décompte bactérien de neuf hôpitaux, obtenues entre 2017 et 2022, les mains des anesthésiologistes et des assistant·es en anesthésie, les sites cutanés des patient·es (narines, aisselles et aines) et les réservoirs de l'appareil d'anesthésie (soupape de réglage de limitation de pression et cadrans d'agent) ont été échantillonnés au début et à la fin de chaque cas. Les échantillons sur l'ensemble de robinets d'arrêt intraveineux des patient·es ont été prélevés à la fin de chaque cas. L'isolement de ≥ 1 UFC de staphylocoque doré, de staphylocoque doré résistant à la méthicilline, d'entérocoque, d'entérocoque résistant à la vancomycine, de staphylocoque à Gram négatif (c.-à-d. Klebsiella, Acinetobacter, Pseudomonas et Enterobacter spp.) ou à coagulase négative a été comparé pour les échantillons de réservoir retournant ≥ 100 UFC vs ceux qui comportaient < 100 UFC. RéSULTATS: Des bactéries pathogènes ont été isolées dans 24 % (7601/31 783) des échantillons de réservoir, 93 % (98/105) des salles d'opération et 83 % (2170/2616) des cas. Le rapport entre le nombre total d'isolats d'agents pathogènes et le nombre total d'UFC était de < 0,0003 %. Les échantillons pris sur les réservoirs d'appareils d'anesthésie ont retourné ≥ 100 UFC dans 44 % (2262/5150) des cas. Vingt-trois pour cent des échantillons retournés ≥ 100 UFC étaient positifs pour ≥ 1 agent pathogène bactérien (521/2262; limite de confiance inférieure à 99 %, 22 %) vs 3 % des échantillons retournant < 100 UFC (96/2888 ; 99 % de la limite supérieure, 4 %). CONCLUSION: Les échantillons pris sur les réservoirs de l'appareil d'anesthésie comportant < 100 UFC étaient associés à une détection négligeable d'agents pathogènes. Ce seuil peut être utilisé pour l'évaluation du nettoyage final, de routine et entre les cas de l'appareil et de l'équipement d'anesthésie. Une telle rétroaction peut être utile parce que la prévalence de 44 % de ≥ 100 UFC était comparable aux 46 % (25/54) rapportés précédemment dans un autre hôpital.

Estimation of the contribution to intraoperative pathogen transmission from bacterial contamination of patient nose, patient groin and axilla, anesthesia practitioners' hands, anesthesia machine, and intravenous lumen.

BACKGROUND: Earlier studies showed net cost saving from anesthesia practitioners' use of a bundle of infection prevention products, with feedback on monitored Staphylococcus aureus intraoperative transmission. ESKAPE pathogens also include Enterococcus and gram-negative pathogens: Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter. We evaluated whether bacterial contamination of patient nose, patient groin and axilla, anesthesia practitioners' hands, anesthesia machine, and intravenous lumen all contribute meaningfully to ESKAPE pathogen transmission within anesthesia work areas. METHODS: The retrospective cohort study used bacterial count data from nine hospitals, 43 months, and 448 ESKAPE pathogen transmission events within anesthesia areas of 86 operating rooms. Transmission was measured within and between pairs of successive surgical cases performed in the same operating room on the same day. RESULTS: There were 203 transmission events with S. aureus, 72 with Enterococcus, and 173 with gram negatives. ESKAPE pathogens in the nose contributed to transmission for 50% (99% confidence limit ≥45%) of case pairs, on the groin or axilla for 54% (≥49%), on the hands for 53% (≥47%), on the anesthesia machine for 21% (≥17%), and in the intravenous lumen for 24% (≥20%). ESKAPE pathogens in the nose started a transmission pathway for 27% (≥22%) of case pairs, on the groin or axilla for 24% (≥19%), on the hands for 38% (≥33%), on the anesthesia machine for 11% (≥7.6%), and in the intravenous lumen for 8.0% (≥5.3%). All P ≤ 0.0022 compared with 5%. CONCLUSIONS: To prevent intraoperative ESKAPE pathogen transmission, anesthesia practitioners would need to address all five categories of infection control approaches: nasal antisepsis (e.g., povidone-iodine applied the morning of surgery), skin antisepsis (e.g., chlorhexidine wipes), hand antisepsis with dispensers next to the patient, decontamination of the anesthesia machine before and during anesthetics, and disinfecting caps for needleless connectors, disinfecting port protectors, and disinfecting caps for open female Luer type connectors.

Most hospital patients at risk for bacterial infection undergo an anesthetic: implications for infection control practices related to the anesthesia workspace.

PURPOSE: Even with nearly 100% compliance with prophylactic antibiotic protocols, many surgical patients (> 5%) develop surgical site infections, some caused by pathogens transmitted from the anesthesia workspace (e.g., anesthesia machine), including multidrug-resistant Staphylococcus aureus. Reducing contamination of the anesthesia workspace substantively reduces the risk of surgical site infections. We estimated the percentage of hospital patients at risk for health care-associated infections who may benefit from the application of basic preventive measures under the control of anesthesia practitioners (e.g., their hand hygiene). METHODS: We conducted a retrospective cohort study which included every patient admitted to the University of Miami Health System from April 2021 through March 2022 for hospitalization, surgery, emergency department visits, or outpatient visits. Lists were created for the start date and times of every parenteral antibiotic administered and every anesthetic. RESULTS: Among 28,213 patient encounters including parenteral antibiotic(s), more than half (64.3%) also included an anesthetic (99% confidence interval, 62.2 to 66.6). The hypothesis that most antibiotics were administered during encounters when a patient underwent an anesthetic was accepted (P < 0.001). This observation may seem counterintuitive because parenteral antibiotics were administered for fewer than half of the 53,235 anesthetics (34.2%). The result was a consequence of most anesthetics (63.5%) at the health system being conducted in nonoperating room locations, and only 7.2% of such patients received a parenteral antibiotic. CONCLUSIONS: Because approximately two-thirds of patients who receive an intravenous antibiotic also undergo an anesthetic, greater use of effective infection control measures in the anesthesia operating room workspace has the potential to substantively reduce overall rates of hospital infections.

RéSUMé: OBJECTIF: Même avec un respect de près de 100 % des protocoles antibiotiques prophylactiques, bon nombre de patients et patientes en chirurgie (> 5 %) développent des infections du site opératoire, dont certaines sont causées par des agents pathogènes transmis par l'espace de travail anesthésique (p. ex. appareil d'anesthésie), y compris un staphylocoque doré multirésistant. La réduction de la contamination de l'espace de travail anesthésique réduit considérablement le risque d'infections du site opératoire. Nous avons estimé le pourcentage de patientes et patients hospitalisé·es à risque d'infections associées aux soins de santé qui pourraient bénéficier de l'application de mesures préventives de base sous le contrôle de praticiens et praticiennes d'anesthésie (par exemple, leur hygiène des mains). MéTHODE: Nous avons mené une étude de cohorte rétrospective qui comprenait toutes les personnes admises au Système de santé de l'Université de Miami d'avril 2021 à mars 2022 pour une hospitalisation, une intervention chirurgicale, des visites aux urgences ou des consultations externes. Des listes ont été créées pour la date et l'heure de début de chaque antibiotique parentéral administré et de chaque anesthésique. RéSULTATS: Parmi les 28 213 consultations avec les patient·es comprenant des antibiotiques parentéraux, plus de la moitié (64,3 %) comportaient également un anesthésique (intervalle de confiance à 99 %, 62,2 à 66,6). L'hypothèse selon laquelle la plupart des antibiotiques étaient administrés lors de rencontres lorsqu'une personne bénéficiait d'une anesthésie a été acceptée (P < 0,001). Cette observation peut sembler contre-intuitive, car des antibiotiques parentéraux ont été administrés pour moins de la moitié des 53 235 anesthésiques (34,2 %). En effet, la plupart des anesthésies (63,5 %) ont été administrées en dehors de la salle d'opération, et seulement 7,2 % de cette patientèle a reçu un antibiotique parentéral. CONCLUSION: Étant donné qu'environ les deux tiers des patientes et patients qui reçoivent un antibiotique par voie intraveineuse bénéficient également d'une anesthésie, une plus grande utilisation de mesures efficaces de contrôle des infections dans l'espace de travail anesthésique de la salle d'opération pourrait réduire considérablement les taux globaux d'infections hospitalières.

Quantifying and Interpreting Inequality in Surgical Site Infections per Quarter Among Anesthetizing Locations and Specialties.

Background Earlier studies have shown that prevention of surgical site infection can achieve net cost savings when targeted to operating rooms with the most surgical site infections. Methodology This retrospective cohort study included all 231,057 anesthetics between May 2017 and June 2022 at a large teaching hospital. The anesthetics were administered in operating rooms, procedure rooms, radiology, and other sites. The 8,941 postoperative infections were identified from International Classification of Diseases diagnosis codes relevant to surgical site infections documented during all follow-up encounters over 90 days postoperatively. To quantify the inequality in the counts of infections among anesthetizing locations, the Gini index was used, with the Gini index being proportional to the sum of the absolute pairwise differences among anesthetizing locations in the counts of infections. Results The Gini index for infections among the 112 anesthetizing locations at the hospital was 0.64 (99% confidence interval = 0.56 to 0.71). The value of 0.64 is so large that, for comparison, it exceeds nearly all countries' Gini index for income inequality. The 50% of locations with the fewest infections accounted for 5% of infections. The 10% of locations with the most infections accounted for 40% of infections and 15% of anesthetics. Among the 57 operating room locations, there was no association between counts of cases and infections (Spearman correlation coefficient r = 0.01). Among the non-operating room locations (e.g., interventional radiology), there was a significant association (Spearman r = 0.79). Conclusions Targeting specific anesthetizing locations is important for the multiple interventions to reduce surgical site infections that represent fixed costs irrespective of the number of patients (e.g., specialized ventilatory systems and nightly ultraviolet-C disinfection).

The efficacy of multifaceted versus single anesthesia work area infection control measures and the importance of surgical site infection follow-up duration.

BACKGROUND: Earlier a randomized trial showed efficacy of a multifaceted intervention approach for reducing surgical site infection: hand hygiene, vascular care, environmental cleaning, patient decolonization (nasal povidone iodine, chlorhexidine wipes), with feedback on pathogen transmission. The follow-up prospective observational study showed effectiveness when applied to all operating rooms of an inpatient surgical suite. In practice, many organizations will at baseline not be using conditions equivalent to the control groups but instead functionally have had ongoing a single intervention for infection control (e.g., encouraging better hand hygiene). Organizations also differ in how well and long they survey every surgical patient for postoperative surgical site infection. Thus, estimation of the expected net cost savings from implementing multifaceted intervention depends on the relative efficacy of multifaceted approach versus single intervention approaches and on the incidence of surgical site infection, the latter depending itself on the monitoring period for infection development. METHODS: The retrospective cohort analysis included 4865 patients from two single intervention and two multifaceted studies, each of the four studies with matched control groups. We used Poisson regression with robust variance to estimate the relative risk reduction in surgical site infections for the multifaceted approach versus single interventions and, with 30-day follow-up versus ≥60-day follow-up for infection. RESULTS: The multifaceted approach was associated with an estimated 68% reduction in postoperative surgical site infections relative to single interventions (risk ratio 0.32, 97.5% confidence interval 0.15-0.70, P = 0.001). There were approximately 2.61-fold more surgical site infections detected with follow-up for at least 60 days of medical records relative to 30 days of records reviewed (97.5% CI 1.62 to 4.21, P < 0.001). CONCLUSIONS: An evidence-based, multifaceted approach to anesthesia work area infection control can generate substantial reductions in surgical site infections. A follow-up period of at least 60-days is indicated for infection detection.

Estimating costs of anesthesia supplies for intraoperative infection control.

BACKGROUND: Some costs for anesthesia supplies to reduce intraoperative infections depend on the procedure and duration of the case. For regular anesthesia supplies and medications, costs are linearly related to American Society of Anesthesiologists' Relative Value Guide units, known for nearly all cases in the United States of America. We hypothesized linear association between costs of infection control items and anesthesia units. METHODS: A prospective observational study of 38 surgical cases was performed. Usage of anesthesia infection control supplies was recorded: alcohol hand dispensers, microfiber cloths for machine disinfection, and disinfecting and cleaning caps for syringe tips, Luer connectors, and stopcocks. Cost per case was calculated using 2022 US dollar payments for those items. RESULTS: Using least squares linear regression to associate the anesthesia units (base + time) with supply costs, in addition to intercept and linear slope, none of 5 potential extra non-linear terms were significant (all P ≥ .46). Further assessment showed lack of fit to a quadratic model. Pearson linear correlation coefficient between cost and units was 0.88. An example was created showing how to forecast annual infection control supply costs for anesthesia based on the linear model. CONCLUSIONS: For purposes of predicting intraoperative anesthesia supplies to reduce bacterial transmission in the anesthesia workspace, a valid approach is to assume a linear association with the total anesthesia units, a predictor generally known for all anesthetics.

The importance of targeting intraoperative transmission of bacteria with antibiotic resistance and strain characteristics.

BACKGROUND: Evidence-based intraoperative infection control measures can reduce Staphylococcus aureus transmission and infections. We aimed to determine whether transmitted S. aureus isolates were associated with increased risk of multidrug resistance and associated traits. METHODS: S. aureus isolates obtained from intraoperative environmental, patient skin, and provider hand reservoirs among 274 operating room case pairs (1st and 2nd case of the day) across 3 major academic medical centers from March 2009 to February 2010 underwent systematic-phenotypic-genomic analysis to identify clonal transmission events. The association of clonal S. aureus transmission with multidrug resistance and resistance traits was investigated. Transmission dynamics were characterized. RESULTS: Transmitted isolates (N=58) were associated with increased risk of multi-drug antibiotic resistance [33% (19/58) transmitted vs. 10% (12/115) other isolates, risk ratio 3.14, 99% CI 1.34-7.38, P=0.0006]. Transmission was associated with a significant increase in resistance traits including mecA [40% transmitted isolates vs. 17% other isolates, risk ratio 2.28, P=0.0026] and ant (6)-Ia [26% transmitted isolates vs. 9% other isolates, risk ratio 2.97, P=0.0050]. Provider hands were a frequent reservoir of origin, between-case a common mode of transmission, and patient skin and provider hands frequent transmission locations for multidrug resistant pathogens. CONCLUSIONS: Intraoperative S. aureus transmission was associated with multidrug resistance and resistance traits. Proven infection control measures should be leveraged to target intraoperative transmission of multidrug resistant pathogens.

Patient Safety in Anesthesia: Hand Hygiene and Perioperative Infection Control.

Purpose of Review: This review highlights the importance of the anesthesia team in minimizing perioperative infection risks and prevention of surgical site infection. Due to the immense financial and patient care burden that results from perioperative infection, a foundational knowledge in preventive measures is essential. Recent Findings: Perioperative infection control, the role of the anesthesia team in reducing infection risk, and more specifically the outsized importance of hand hygiene in this space have become increasingly apparent. Maintenance of workspace cleanliness along with hand hygiene forms the cornerstone of preventing microbial transmission. Unfortunately, improvements around perioperative infection control are lacking. Summary: The importance of the anesthesia team in maintaining proper hand hygiene, a clean work environment, and appropriate patient conditions to minimize risk of perioperative infection cannot be overstated. Poor clinical outcomes, economic burden, and external pressure from payers highlight the need for anesthesia providers to have an up-to-date knowledge of best practices in this area. In this article, we will review the current recommendations for hand hygiene practices and perioperative infection prevention.

Molecular characterisation and epidemiology of transmission of intraoperative Staphylococcus aureus isolates stratified by vancomycin minimum inhibitory concentration (MIC).

Background: Reduced vancomycin susceptibility in Staphylococcus aureus (S. aureus) is considered a more pathogenic strain characteristic and is associated with treatment failure. We aimed to characterise the epidemiology of intraoperative transmission of S. aureus isolates with reduced vancomycin susceptibility. Methods: S. aureus isolates (N=173) collected from 274 randomly selected operating room environments at three major academic medical centres in 2009-2010 were characterised by vancomycin minimum inhibitory concentration (MIC). We aimed to characterise the transmission dynamics for VISA and isolates with relatively reduced vancomycin (MIC= 2µg/mL) susceptibility at the range of therapeutic differentiation. Results: Intraoperative S. aureus MIC was 1.38 ± 0.34 µg/mL. No VISA isolates were identified (95% upper confidence limit 2.1%) and those with an MIC of 2 µg/mL accounted for 12.72% (22/173) of all isolates. MIC=2 µg/mL isolates were more frequently cultured from the hands of healthcare providers [19.3% (16/83)] versus otherwise [6.7% (6/90)], with unadjusted risk ratio 2.89, P=0.021, and from patients with >2 major comorbidities [25.0% (8/32)] versus otherwise [9.9% (14/141)], with unadjusted risk ratio 2.52, P=0.035. Both were significant when tested simultaneously. The adjusted relative risk for provider hands was 2.77 (95% CI 1.15 to 6.69, P=0.024). The adjusted relative risk for patients with >2 major comorbidities was 2.37 (95% CI 1.11 to 5.05, P=0.026). MIC=2µg/mL was not associated with greater risk of clonal transmission (unadjusted P=0.34, adjusted P=0.18). Conclusion: Intraoperative VISA is a rare event. S. aureus isolates MIC=2µg/mL isolates were not associated with increased risk of intraoperative transmission. The epidemiology of detected intraoperative transmission is consistent with Centers for Disease Control guidelines.

Average and longest expected treatment times for ultraviolet light disinfection of rooms.

BACKGROUND: Planning Ultraviolet-C (UV-C) disinfection of operating rooms (ORs) is equivalent to scheduling brief OR cases. The study purpose was evaluation of methods for predicting surgical case duration applied to treatment times for ORs and hospital rooms. METHODS: Data used were disinfection times with a 3-tower UV-C disinfection system in N=700 rooms each with ≥100 completed treatments. RESULTS: The coefficient of variation of mean treatment duration among rooms was 19.6% (99% confidence interval [CI] 18.2%-21.0%); pooled mean 18.3 minutes among the 133,927 treatments. The 50th percentile of coefficients of variation among treatments of the same room was 27.3% (CI 26.3%-28.4%), comparable to variabilities in durations of surgical procedures. The ratios of the 90th percentile to mean differed among rooms. Log-normal distributions had poor fits for 33% of rooms. Combining results, we calculated 90% upper prediction limits for treatment times by room using a distribution-free method (e.g., third longest of preceding 29 durations). This approach was suitable because, once UV-C disinfection started, the median difference between the duration estimated by the system and actual time was 1 second. CONCLUSIONS: Times for disinfection should be listed as treatment of a specific room (e.g., "UV-C main OR16"), not generically (e.g., "UV-C"). For estimating disinfection time after single surgical cases, use distribution-free upper prediction limits, because of considerable proportional variabilities in duration.

Effectiveness and feasibility of an evidence-based intraoperative infection control program targeting improved basic measures: a post-implementation prospective case-cohort study.

STUDY OBJECTIVE: A randomized controlled study demonstrated that an optimized intraoperative infection control program targeting basic preventive measures can reduce Staphylococcus aureus transmission and surgical site infections. In this study we address potential limitations of operating room heterogeneity of infections and compliance with behavioral interventions following adoption into clinical practice. DESIGN: A post-implementation prospective case-cohort study. SETTING: Twenty-three operating rooms at a large teaching hospital. PATIENTS: A total of 801 surgical patients [425 (53%) women; 350 (44%) ASA > 2, age 54.6 ± 15.9 years] were analyzed for the primary and 804 for the secondary outcomes. INTERVENTIONS: A multifaceted, evidence-based intraoperative infection control program involving hand hygiene, vascular care, and environmental cleaning improvements was implemented for 23 operating room environments. Bacterial transmission monitoring was used to provide monthly feedback for intervention optimization. MEASUREMENTS: S. aureus transmission (primary) and surgical site infection (secondary). MATERIALS AND METHODS: The incidence of S. aureus transmission and surgical site infection before (3.5 months) and after (4.5 months) infection control optimization was assessed. Optimization was defined by a sustained reduction in anesthesia work area bacterial reservoir isolate counts. Poisson regression with robust error variances was used to estimate the incidence risk ratio (IRR) of intraoperative S. aureus transmission and surgical site infection for the independent variable of optimization. MAIN RESULTS: Optimization was associated with decreased S. aureus transmission [24% before (85/357) to 9% after (42/444), IRR 0.39, 95% CI 0.28 to 0.56, P < .001] and surgical site infections [8% before (29/360) and 3% after (15/444) (IRR 0.42, 95% CI 0.23 to 0.77, P = .005; adjusted for American Society of Anesthesiologists' physical status, aIRR 0.45, 95% CI 0.25 to 0.82, P = .009]. CONCLUSION: An optimized intraoperative infection control program targeting improvements in basic preventive measures is an effective and feasible approach for reducing S. aureus transmission and surgical site infection development.

Epidemiology of Enterococcus , Staphylococcus aureus , Klebsiella , Acinetobacter , Pseudomonas , and Enterobacter Species Transmission in the Pediatric Anesthesia Work Area Environment With and Without Practitioner Use of a Personalized Body-Worn Alcohol Dispenser.

BACKGROUND: Personalized body-worn alcohol dispensers may serve as an important tool for perioperative infection control, but the impact of these devices on the epidemiology of transmission of high-risk Enterococcus , Staphylococcus aureus , Klebsiella, Acinetobacter , Pseudomonas , and Enterobacter (ESKAPE) pathogens is unknown. We aimed to characterize the epidemiology of ESKAPE transmission in the pediatric anesthesia work area environment with and without a personalized body-worn alcohol dispenser. METHODS: This controlled before and after study included 40 pediatric patients enrolled over a 1-year study period. Two groups of operating room cases were compared: (1) operating room cases caring for patients with usual care (December 17, 2019, to August 25, 2020), and (2) operating room cases caring for patients with usual care plus the addition of a personalized, body-worn alcohol hand rub dispenser (September 30, 2020, to December 16, 2020). Operating rooms were randomly selected for observation of ESKAPE transmission in both groups. Device use was tracked via wireless technology and recorded in hourly hand decontamination events. RESULTS: Anesthesia providers used the alcohol dispenser 3.3 ± 2.1 times per hour. A total of 57 ESKAPE transmission events (29 treatment and 28 control) were identified. The personalized body-worn alcohol dispenser impacted ESKAPE transmission by increasing the contribution of provider hand contamination at case start (21/29 device versus 10/28 usual care; relative risk, [RR] 2.03; 99.17% confidence interval [CI], 1.025-5.27; P = .0066) and decreasing the contribution of environmental contamination at case end (3/29 device versus 12/28 usual care; RR, 0.24; 99.17% CI, 0.022-0.947; P = .0059). ESKAPE pathogen contamination involved 20% (8/40) of patient intravascular devices. There were 85% (34/40) of preoperative patient skin surfaces contaminated with ≥1 (1.78 ± 0.19 [standard deviation {SD}]) ESKAPE pathogens. CONCLUSIONS: A personalized body-worn alcohol dispenser can impact the epidemiology of ESKAPE transmission in the pediatric anesthesia work area environment. Improved preoperative patient decolonization and vascular care are indicated to address ESKAPE pathogens among pediatric anesthesia work area reservoirs.

Statistical Design of Overnight Trials for the Evaluation of the Number of Operating Rooms That Can Be Disinfected by an Ultraviolet Light Disinfection Robotic System.

Background and objective The number of ultraviolet light disinfection robot systems that are needed for a facility's surgical suite(s) and/or procedure suite(s) depends in part on how many rooms need to be disinfected overnight by each robot and how long this will take. The answer needs to be determined separately for each surgical and procedure suite because those variables vary both among facilities and among operating rooms or procedure rooms within facilities. In this study, we consider statistical designs to assess how many rooms a facility can reliably (≥90% chance) disinfect overnight using an ultraviolet light disinfection robot system. Methods We used 133,927 observed disinfection times from 700 rooms as a population from which repeated samples were drawn with replacement in Monte-Carlo simulations. We used eight-hour and 10-hour shift lengths being multiples of 40 hours for full-time hourly employees. Results One possible strategy that we examined was to estimate total disinfection times by estimating the mean for each room and then summing up the means. However, that did not correctly answer the question of how many rooms can reliably be available for the next day's first case. Summing up a percentile (e.g., 90%) instead also was inaccurate, because the proper percentile depended on the number of rooms. A suitable strategy is a brief trial (e.g., nine nights or 19 nights) with the endpoint being the daily number of rooms disinfected. Empirically, the smallest count of rooms disinfected among nine nights or the second smallest count among 19 nights are 10th percentiles (i.e., ≈90% probability that at least that number of rooms can be disinfected in the future). The drawback is that while this approach gives the probability of a night with fewer rooms disinfected, it does not give information as to how many fewer rooms may either skip ultraviolet decontamination or start late the next workday because disinfection was not completed. Our simulations showed that there is a substantial probability (≥95%) of at most two rooms fewer or one room greater than the 10th percentile with a nine-night trial and one room fewer or greater with a 19-night trial. Conclusions Because probability distributions of disinfection times are heterogeneous both among rooms and among treatments for the same room, each facility should plan to perform its own trial of nine nights or 19 nights. This will provide results that are within two rooms or one room of the correct answer in the long term. This information can be used when planning purchasing decisions, leasing, and technician staffing decisions.

Quantifying and interpreting inequality of surgical site infections among operating rooms.

PURPOSE: The incidence of surgical site infection differs among operating rooms (ORs). However, cost effectiveness of interventions targeting ORs depends on infection counts. The purpose of this study was to quantify the inequality of infection counts among ORs. METHODS: We performed a single-centre historical cohort study of elective surgical cases spanning a 160-week period from May 2017 to May 2020, identifying cases of infection within 90 days using International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes. We used the Gini index to measure inequality of infections among ORs. As a reference, the Gini index for inequality of household disposable income in the US in 2017 was 0.39, and 0.31 for Canada. RESULTS: There were 3,148 (3.67%) infections among the 85,744 cases studied. The 20% of 57 ORs with the most and least infections accounted for 44% (99% confidence interval [CI], 36 to 52) and 5% (99% CI, 2 to 8), respectively. The Gini index was 0.40 (99% CI, 0.31 to 0.50), which is comparable to income inequality in the US. There were more infections in ORs with more minutes of cases (Spearman correlation ρ = 0.68; P < 0.001), but generally not in ORs with more total cases (ρ = 0.11; P = 0.43). Moderately long (3.3 to 4.8 hr) cases had a large effect, having greater incidences of infection, while not being so long as to have just one case per day per OR. There was substantially greater inequality in infection counts among the 557 observed combinations of OR specialty (Gini index 0.85; 99% CI, 0.81 to 0.88). CONCLUSIONS: Inequality of infections among ORs is substantial and caused by both inequality in the incidence of infections and inequality in the total minutes of cases. Inequality in infections among OR and specialty combinations is due principally to inequality in total minutes of cases.

RéSUMé: OBJECTIF: L'incidence d'infections opératoires diffère d'une salle d'opération (SOP) à une autre. Toutefois, le rapport coût-efficacité des interventions ciblant les SOP dépend de l'incidence des infections. Le but de cette étude était de quantifier l'inégalité du nombre d'infections entre les SOP. MéTHODE: Nous avons effectué une étude de cohorte historique et monocentrique des cas chirurgicaux non urgents couvrant une période de 160 semaines allant de mai 2017 à mai 2020. Nous avons identifié les cas d'infection dans les 90 jours suivant l'opération à l'aide des codes de diagnostic de la Classification internationale des maladies, dixième révision, modification clinique. Nous avons utilisé l'indice de Gini pour mesurer l'inégalité des infections entre les SOP. À titre de référence, en 2017, l'indice de Gini pour l'inégalité du revenu disponible des ménages était de 0,39 aux États-Unis et de 0,31 pour le Canada. RéSULTATS: Il y a eu 3148 (3,67 %) infections parmi les 85 744 cas étudiés. Les quintiles des 57 SOP ayant le plus et le moins d'infections représentaient 44 % (intervalle de confiance [IC] 99 %, 36 à 52) et 5 % (IC 99 %, 2 à 8) des infections, respectivement. L'indice de Gini était de 0,40 (IC 99 %, 0,31 à 0,50), ce qui est comparable à l'inégalité des revenus aux États-Unis. Il y avait plus d'infections dans les SOP comptant plus de minutes de cas (corrélation de Spearman ρ = 0,68; P < 0,001), mais généralement pas dans les SOP avec un nombre plus élevé de cas totaux (ρ = 0,11; P = 0,43). Les cas modérément longs (3,3 à 4,8 heures) ont eu un effet important, ayant des incidences plus importantes d'infection, tout en n'étant pas suffisamment longs pour n'avoir qu'un seul cas par jour et par SOP. Une inégalité sensiblement plus prononcée a été remarquée dans le nombre d'infections parmi les 557 combinaisons observées de spécialité de SOP (indice de Gini 0,85; IC 99 %, 0,81 à 0,88). CONCLUSION: L'inégalité des infections entre les SOP est importante et causée à la fois par l'inégalité dans l'incidence des infections et par l'inégalité dans la durée totale (en minutes) des cas. L'inégalité dans les infections entre les SOP et les combinaisons de spécialités est principalement due à l'inégalité dans le nombre total de minutes des cas.

Sample times for surveillance of S. aureus transmission to monitor effectiveness and provide feedback on intraoperative infection control.

BACKGROUND: Reductions in perioperative surgical site infections are obtained by a multifaceted approach including patient decolonization, vascular care, hand hygiene, and environmental cleaning. Associated surveillance of S. aureus transmission quantifies the effectiveness of these basic measures to prevent transmission of pathogenic bacteria and viruses to patients and clinicians, including Coronavirus Disease 2019 (COVID-19). To measure transmission, the observational units are pairs of successive surgical cases in the same operating room on the same day. In this prospective cohort study, we measured sampling times for inexperienced and experienced personnel. METHODS: OR PathTrac kits included 6 samples collected before the start of surgery and 7 after surgery. The time for consent also was recorded. We obtained 1677 measurements of time among 132 cases. RESULTS: Sampling times were not significantly affected by technician's experience, type of anesthetic, or patient's American Society of Anesthesiologists' Physical Status. Sampling times before the start of surgery averaged less than 5 min (3.39 min [SE 0.23], P < 0.0001). Sampling times after surgery took approximately 5 min (4.39 [SE 0.25], P = 0.015). Total sampling times averaged less than 10 min without consent (7.79 [SE 0.50], P < 0.0001), and approximately 10 min with consent (10.22 [0.56], P = 0.70). CONCLUSIONS: For routine use of monitoring S. aureus transmission, when done by personnel already present in the operating rooms of the cases, the personnel time budget can be 10 min per case.