Summary
Background
Anaesthesia induction is a fast-paced, complex activity that involves a high density of hand-to-surface exposures. Hand hygiene (HH) adherence has been reported to be low, which bears the potential for unnoticed pathogen transmission between consecutive patients.
Aim
To study the fit of the World Health Organization's (WHO) five moments of HH concept to the anaesthesia induction workflow.
Methods
Video recordings of 59 anaesthesia inductions were analysed according to the WHO HH observation method considering each hand-to-surface exposure of every involved anaesthesia provider. Binary logistic regression was used to determine risk factors for non-adherence, i.e. professional category, gender, task role, gloves, holding of objects, team size and HH moment. Additionally, half of all videos were recoded for quantitative and qualitative analysis of provider self-touching.
Findings
Overall, 2240 HH opportunities were met by 105 HH actions (4.7%). The drug administrator role (odds ratio (OR): 2.2), the senior physician status (OR: 2.1), donning (OR: 2.6) and doffing (OR: 3.6) of gloves were associated with higher HH adherence. Notably, 47.2% of all HH opportunities were caused by self-touching behaviour. Provider clothes, face, and patient skin were the most frequently touched surfaces.
Conclusion
The high density of hand-to-surface exposures, a high cognitive load, prolonged glove use, carried mobile objects, self-touching, and personal behaviour patterns were potential causes for non-adherence. A purpose-designed HH concept based on these results, involving the introduction of designated objects and provider clothes to the patient zone, could improve HH adherence and microbiological safety.
Keywords
Introduction
Healthcare-acquired infections (HAIs) are still a major public health concern worldwide, leading to an increase in patient morbidity, mortality, and financial costs of hospital stays [
[1]
,[2]
]. Hand hygiene (HH) is generally accepted as the single most influential element in infection prevention and control [[3]
,[4]
]. The ‘My five moments for hand hygiene’ concept (‘five moments’) has been promoted by the World Health Organization (WHO), and is regarded as the gold standard for understanding, training, monitoring, and reporting HH [[5]
,[6]
].The concept represents a fundamental reference point for healthcare workers (HCWs) in a time–space framework and describes the moments when HH is required to interrupt microbial transmission during patient care [
[4]
]. The core of the framework is the definition of the patient zone and critical body sites based on evidence-based hand transmission models [[7]
]. HH is required within the time period between touching two consecutive surfaces that would result in pathogen transmission or infection [[4]
].The ‘five moments’ concept has gained considerable popularity in the last 15 years, becoming the standard for many hospitals and the basis for numerous interventions and reports [
[8]
]. The strength of the concept is its unified approach and simplicity. However, a shared understanding of the zones and the corresponding attribution of all mobile and immobile surfaces might be more demanding than anticipated [[9]
]. This difficulty might be further accentuated in complex settings such as anaesthesia, which might explain the exceptionally low observed adherence of only 10–20% in this setting [[10]
,[11]
]. To better understand the degree of fit of the ‘five moments’ system to the anaesthesia setting, we analysed HH adherence in real-life video observations of anaesthesia inductions.Methods
A full ethics evaluation was waived by the ethics review board of the canton of Zurich based on the Swiss Law for Research on Humans (Req-2016-00173). All study patients and anaesthesia providers were briefed about the study and gave written consent.
Setting
The study was conducted at the University Hospital Zurich, Switzerland, a 900-bed primary and tertiary care centre. General anaesthesia induction was observed in visceral, heart and thoracic surgery, including solid organ transplantation, in a surgical platform of eight operating rooms with an anaesthesia induction room each. All induction rooms were of the same design, with the patient situated in the middle, a respirator at their head, a monitoring unit to their right, an anaesthesia workstation with two workplaces, and a medication cart on wheels.
Anaesthesia induction procedure
Observation was focused on anaesthesia inductions lasting approximately 10–15 min, starting with the application of a pre-anaesthesia induction checklist and ending when the patient was intubated, ventilated, and the tube secured [
[12]
]. Observations were limited to patients with American Society of Anaesthesiologists physical status classifications 2–4 who received general anaesthesia.The anaesthesia care team usually consists of a specialized registered nurse, an anaesthesia registrar, and an anaesthesia consultant who are all proficient in taking one of the following three roles: (a) an ‘airway manager’ at the head of the patient who secures the patient's airway through bag-mask ventilation, intubation, and suction if necessary; (b) a ‘drug administrator’, positioned at the side of the patient, who administers drugs such as opioids, hypnotics, and relaxants, and monitors the vital signs; (c) a ‘supporter’, positioned on the opposite side of the patient, who hands the airway equipment to the ‘airway manager’. In some cases, a fourth person – usually a senior anaesthesia consultant – supervises and coaches the team. Habitually, the most senior anaesthesia practitioner leads the team in any of the roles. Team size may vary between two and six people.
During the execution of the pre-induction checklist, the patient is preoxygenated to an expiratory oxygen fraction of 0.8 or for ≥5 min. Then, the opioid is administered, followed by a check of vital signs. Next, hypnotic drugs (mostly propofol, in some rare cases thiopental) are given, the bag-mask ventilation starts and a relaxant is administered (rocuronium or atracurium). After a few minutes of bag-mask ventilation, the patient is intubated, the correct position of the tube is checked by auscultation, capnometry, and movement of the chest, and the tube is secured with adhesive tape.
The WHO hand hygiene observation method
The study was based on an adapted, simplified version of the ‘five moments’ concept that has been adopted by Ontario (CA, USA) and many Swiss hospitals, including the University Hospital Zurich, for its simplicity and assumed increased microbiologic safety [
[5]
,13
, 14
, 15
]. It consists of the following four moments: Moment 1: Before touching a patient or their immediate surroundings; Moment 2: Before aseptic tasks; Moment 3: After body fluid exposure risk; Moment 4: After touching a patient or their immediate surrounding.In 2015, the operating theatre's interdisciplinary infection prevention group established the patient zone and healthcare zone following the simplified ‘five moments’ concept for all theatres and induction rooms. A permanent training programme educated operating theatre personnel on the concept, including the study population.
Video-based observation of hand hygiene moments
Anaesthesia inductions were recorded simultaneously by two wall-mounted GoPro cameras (GoPro, Inc., San Mateo, CA, USA) at a 90° angle from each other and ∼50 cm above eye level. The videos were then viewed and coded using the software Interact from Mangold (Mangold International GmbH, Arnsdorf, Germany) by a human factors specialist and an infection prevention specialist nurse, both with extensive experience in the simplified ‘five moments’. To increase reliability, 20% of the videos were double-coded and discrepancies were solved through in-depth discussions resulting in an interrater agreement >80%. They used the WHO observation method meticulously considering every hand-to-surface exposure (HSE) that delimitated HH opportunities as departure surface and destination surface. The surfaces were coded according to the zones and critical sites as introduced in the surgical study platform and further categorized into 19 sites in the patient zone, 15 in the healthcare zone, and eight critical sites (Supplementary Table S1). All HH actions were registered, but those outside an opportunity were excluded from the analysis. Glove use was coded as either donning or doffing within an HH opportunity or wearing during the whole opportunity. The same three values were used for carrying objects during an HH opportunity.
Professional categories (specialized nurse, resident, consultant) and task roles (airway manager, drug administrator, supporter, supervisor) were noted. The total number of people in the room during each HH opportunity was registered. The duration of each HH opportunity was calculated by the timestamp of their limiting hand-to-surface exposures.
When it was realized during the analysis that many HH opportunities involved self-touching (clothes, skin, or face) either as an origin or destination surface, 30 videos (50% of the original sample) were randomly selected to be re-coded according to the type of self-touch gesture, i.e. action (purposefully directed gesture, e.g. donning a mask), discharge (quick, unconscious gesture without physical purpose, e.g. scratching head), and stabilization (resting gesture, e.g. crossing arms). In parallel, we described the course of action in the same subset of videos in writing.
Analysis
Binary logistic regressions were calculated with HH action during an HH opportunity as the outcome. Odds ratios were calculated to determine specific risk factors for HH adherence (i.e. professional category, gender, task role, gloves, holding of objects, team size during opportunity and hand hygiene moment). Analyses were conducted using SPSS Statistics (Version 26, IBM, Armonk, NY, USA). Additionally, the written course of action was subject to thematic qualitative analysis to further describe the complex behavioural context of self-touching, HH adherence, and glove use.
Results
In total, 10 h, 2 min, and 12 s of video recording were coded, representing 59 anaesthesia inductions with a mean duration of 10 min and 12 s (SD: 213.4 s). Seventy-four (40.5% females) anaesthesia providers were observed; 26 nurses, 25 residents, and 23 senior physicians. The median team size was three (range: 2–6). In total, they encountered 2240 HH opportunities with an average of 38 opportunities (SD: 18.1) per induction. Mean HH opportunities per provider were 18.7 (SD: 13.8) opportunities per scenario.
Hand hygiene adherence
The 2240 opportunities were met by 105 HH actions, resulting in an overall HH adherence of 4.7%. Another 63 HH actions performed outside of HH opportunities were excluded from the analysis. Table I displays HH opportunities, actions, adherence rates, and potential determinants. Assuming 15 s per HH action, the time for HH would average 4 min 40 s per induction to reach 100% adherence.
Table IHand hygiene opportunities and actions, stratified according to potential determinants
| Variable | HH opportunities | HH actions | Adherence | OR | 95% CI |
|---|---|---|---|---|---|
| Total | 2240 | 105 | 4.7% | ||
| Professional category | |||||
| Resident | 548 (24.5%) | 21 | 3.8% | 1 | |
| Senior physicians | 701 (31.3%) | 53 | 7.1% | 2.1 | 1.2–3.5 |
| Nurse | 962 (42.9%) | 31 | 3.2% | 0.8 | 0.5–1.5 |
| Gender | |||||
| Female | 864 (38.6%) | 43 | 5.0% | 1 | |
| Male | 1376 (61.4%) | 62 | 4.5% | 0.9 | 0.6–1.3 |
| Task role | |||||
| Supporter | 886 (39.6%) | 32 | 3.6% | 1 | |
| Drug administrator | 761 (34%) | 58 | 7.6% | 2.2 | 1.4–3.4 |
| Airway manager | 555 (24.8%) | 15 | 2.7% | 0.7 | 0.4–1.4 |
| Supervisor | 37 (1.7%) | 0 | 0.0% | 0 | |
| Gloves | |||||
| No gloves involved | 1169 (52.2%) | 76 | 6.5% | 1 | |
| Gloves worn during entire opportunity | 914 (40.8%) | 0 | 0.0% | ||
| Doffing gloves during opportunity | 100 (4.5%) | 20 | 20.0% | 3.6 | 2.1–6.2 |
| Donning gloves during opportunity | 57 (2.5%) | 9 | 15.8% | 2.6 | 1.3–5.7 |
| Holding of objects | |||||
| Hands free | 1309 (58.4%) | 76 | 5.5% | 1 | |
| Hands busy (holding something with at least one hand) | 791 (35.3%) | 0 | 0.0% | ||
| Team size during opportunity | |||||
| 2 members | 394 (17.6%) | 24 | 6.1% | 1 | |
| 3 members | 1495 (66.7%) | 63 | 4.2% | 0.7 | 0.4–1.1 |
| 4 members | 231 (10.3%) | 14 | 6.1% | 1 | 0.5–2.0 |
| 5 members | 117 (5.2%) | 4 | 3.4% | 0.6 | 0.2–1.6 |
| 6 members | 3 (0.1%) | 0 | 0.0% | ||
| HH moment | |||||
| Moment 1 (outside–inside) | 875 (39.1%) | 29 | 3.3% | 1 | |
| Moment 2 (before critical site) | 305 (13.6) | 16 | 5.2% | 1.6 | 0.9–3.0 |
| Moment 3 (after critical site) | 197 (8.8) | 19 | 9.6% | 3.1 | 1.7–5.7 |
| Moment 4 (inside–outside) | 863 (38.5) | 41 | 4.8% | 1.5 | 0.9–2.4 |
HH, hand hygiene; OR, odds ratio; CI, confidence interval.
a P < 0.01.
Detailed analysis of departure and destination surfaces
Table II lists the ten most frequent departure and destination surfaces, and Table III the most frequent delimitating hand transition surface pairs.
Table IIThe ten most frequent hand hygiene opportunity departure and destination surfaces
| HH departure/destination surface | Frequency | % |
|---|---|---|
| Total HH opportunities | 2240 | 100 |
| Most frequent origin surface | ||
| HCW clothes | 326 | 14.6 |
| HCW face/skin | 182 | 8.1 |
| Patient intact skin | 179 | 8.0 |
| Various others | 177 | 7.9 |
| Drawer | 125 | 5.6 |
| Bed | 95 | 4.2 |
| Pen | 70 | 3.1 |
| Patient mouth | 66 | 2.9 |
| Patient documents | 66 | 2.9 |
| Oxygen mask | 65 | 2.9 |
| Most frequent destination surface | ||
| HCW clothes | 330 | 14.7 |
| HCW face/skin | 182 | 8.1 |
| Patient intact skin | 175 | 7.8 |
| Various others | 161 | 7.2 |
| Syringe | 152 | 6.8 |
| IV access | 111 | 5 |
| Drawer | 110 | 4.9 |
| Oxygen mask | 97 | 4.3 |
| Bed | 79 | 3.5 |
| Patient documents | 65 | 2.9 |
HH, hand hygiene; HCW, healthcare worker; IV, intravenous.
a This includes all other objects (e.g. equipment from the operating room that is temporarily placed in the room).
Table IIIThe most frequent pathways observed, sorted by frequency of hand hygiene opportunities
| Origin and destination surface | Frequency | % |
|---|---|---|
| Moment 1 (healthcare zone → patient zone) | 875 | 100 |
| Drawer → others patient zone | 36 | 4.1 |
| HCW clothes → others patient zone | 34 | 3.9 |
| HCW clothes → clipboard | 33 | 3.8 |
| Pen → patient documents | 32 | 3.7 |
| HCW clothes → intact skin | 29 | 3.3 |
| HCW clothes → bed | 28 | 3.2 |
| HCW clothes → oxygen mask | 28 | 3.2 |
| HCW clothes → patient intact skin | 26 | 3 |
| HCW face/skin → bed | 24 | 2.7 |
| Tape roll → patient intact skin | 22 | 2.5 |
| Moment 2 (any site→clean site) | 305 | 100 |
| Others (inside or outside patient zone) → syringe | 17 | 5.6 |
| Others (inside or outside patient zone) → laryngoscope spatula | 14 | 4.6 |
| HCW clothes → syringe | 14 | 4.6 |
| HCW face/skin → IV access | 13 | 4.3 |
| Infusion → IV access | 13 | 4.3 |
| Patient intact skin → syringe | 13 | 4.3 |
| Drawer → syringe | 11 | 3.6 |
| Drawer → IV access | 10 | 3.3 |
| Checklist → syringe | 9 | 3 |
| HCW clothes → IV access | 9 | 3 |
| HCW face/skin → syringe | 17 | 5.6 |
| Moment 3 (body fluid site → any site) | 197 | 100 |
| Patient mouth → oxygen mask | 29 | 14.7 |
| Contaminated laryngoscope → oxygen mask | 16 | 8.1 |
| Patient mouth → patient clothes | 12 | 6.1 |
| IV access → HCW face/skin | 12 | 6.1 |
| IV access → HCW clothes | 10 | 5.1 |
| Syringe → HCW clothes | 9 | 4.6 |
| Syringe → HCW face/skin | 8 | 4.1 |
| Contaminated laryngoscope → others | 7 | 3.6 |
| Syringe → drawer | 7 | 3.6 |
| Patient mouth → ambu bag | 6 | 3 |
| Moment 4 (patient zone → healthcare zone) | 863 | 100 |
| Patient intact skin → HCW clothes | 47 | 5.4 |
| Bed → HCW clothes | 45 | 5.2 |
| Clipboard → HCW clothes | 35 | 4.1 |
| Others → drawer | 31 | 3.6 |
| Others → HCW clothes | 31 | 3.6 |
| Patient intact skin → tape roll | 31 | 3.6 |
| Others → HCW face/skin | 31 | 3.6 |
| Oxygen mask → HCW clothes | 29 | 3.4 |
| Patient intact skin → tape roll | 21 | 2.4 |
| Checklist → HCW clothes | 16 | 1.9 |
HCW, healthcare worker; IV, intravenous.
a Laryngoscope was regarded as contaminated after it had been in the patient's mouth.
In the 30 recoded videos, 631 (47.2%) out of 1338 HH opportunities were caused by self-touching events (Table IV) coded as action in 399 (63.2%), as discharge in 108 (17.1%), and as stabilization in 123 (19.5%). Each self-touching event triggered two HH opportunities, one when directing the hand to the own body, which is regarded as healthcare zone, and one on the way back to the patient. Only in rare cases, when an additional surface outside the patient zone was touched in sequence, did no HH opportunity occur before or after a self-touch.
Table IVSelf-touching events as departure or destination surface in hand hygiene opportunities
| Self-touching event | No. | % |
|---|---|---|
| T-shirt hip | 71 | 21.1 |
| T-shirt pocket | 59 | 17.6 |
| Trousers pocket | 36 | 10.7 |
| Mask | 31 | 9.2 |
| T-shirt | 27 | 8.0 |
| Arms | 26 | 7.7 |
| Trousers | 16 | 4.8 |
| Nose | 15 | 4.5 |
| Eye | 10 | 3.0 |
| Neck | 10 | 3.0 |
| Cap | 9 | 2.7 |
| Ear | 6 | 1.8 |
| Chin | 4 | 1.2 |
| Forehead | 4 | 1.2 |
| Mouth | 2 | 0.6 |
| Glasses | 1 | 0.3 |
| Hair | 1 | 0.3 |
| Other hand | 1 | 0.3 |
| Total | 336 | 100 |
Total number is smaller than hand hygiene (HH) opportunities because each self-touch event results potentially in two HH opportunities. Healthcare workers did not wear face shields or protective glasses in this hospital before the COVID-19 pandemic, therefore this equipment is not listed.
a Healthcare workers (HCWs) wore protective caps. This was a single case where an HCW briefly took off the cap to scratch the hair.
Qualitative appraisal of self-touching behaviour
The results of the qualitative analysis revealed a clustering of HH opportunities according to specific roles and phases during the anaesthesia induction and they evidenced the relevance of individual behaviour patterns and specific objects.
The role of airway management involved two phases with typical trans-individual self-touching behaviours, the uneventful phase of oxygenation when the airway manager used one hand to hold the ventilation mask on to the face of the patient and had to wait until the blood saturated with oxygen. This frequently led to a stabilizing self-touching, putting one unoccupied hand on the hip thereby touching the T-shirt. Sometimes drug administrators demonstrated similar patterns while waiting for the drugs to act; directly injecting drugs was considered a Moment 2 before the invasive HH moment. The other behaviour pattern of airway managers happened shortly after intubation when checking the correct placement of the tube with the stethoscope that she had around her neck or in the trouser pocket, leading to many consecutive self-touching action events of the action type. Contrarily to the stabilization during an uneventful phase, this was usually a hectic moment. The role of the supporter usually created self-touching while using the pen (hospital zone) to take notes on the clipboard (patient zone) stored in the T-shirt chest pocket. Supervisors often produced stabilization self-touching, crossing their arms in front of the chest or hands behind their back while observing the junior staff. A relatively small number of objects were associated with self-touching, including caps, masks, T-shirts, trousers, clipboards, stethoscopes, and pens, the latter three also independently of self-touching.
Beyond roles, phases, and objects, self-touching occurred linked to individual behaviour patterns. Such inter-individual differences were not limited to self-touching but could also be observed in the density of HH opportunities in general. For example, a coughing provider repetitively held her hand in front of the mask while coughing, touching it each time; another provider touched his left upper arm repetitively, while others showed habits of wiping with their hand over the T-shirt at the hip level or over the chest as discharge gesture. The same person also touched the environment frequently without an obvious task goal. Such touching habits created clusters that inflated the overall number of HH opportunities during anaesthesia induction.
Discussion
Anaesthesia induction is a setting with a high patient throughput and intense hands-on care in a constrained environment. Therefore, indirect hand transmission of potential pathogens between patients in the absence of correct hand hygiene is very likely. Considering each hand-to-surface exposure in 59 video-captured inductions and using an adapted version of the WHO ‘five moments’ revealed several novel and relevant findings. First, the results confirmed an extremely high density of HH opportunities and low adherence of 4.7%, with a high proportion of HH actions outside opportunities. Second, self-touching of providers generated half of all observed HH opportunities. Likewise, some specific objects in the environment, including drawers, pens, tape rolls, and stethoscopes, inflated the need for HH even further. Third, we found several factors independently associated with a slightly better HH adherence, namely senior physician status, the drug administrator role, and opportunities before donning and after doffing gloves, whereas holding an object was independently associated with low HH adherence. Together, these findings can guide system redesign to reduce the abundance of HH opportunities.
The high density of HH opportunity was expected, given the hands-on and fast-paced activity during anaesthesia induction, involving injections, intubation, touching monitors, and controlling life-support equipment – producing incessant transitions between the healthcare zone, patient zone, and critical body sites. And since the risk of exposure to body fluids is common in this setting, gloves are frequently indicated for only brief manipulations. Furthermore, the high cognitive load during anaesthesia induction does not allow for deliberate focus on HH at every moment [
[16]
]. A high density of HH opportunities has been interpreted to lead to HH adherence as low as 2.9–10% in two anaesthesia studies [[10]
,[17]
]. The authors of both studies concluded that full HH adherence is not feasible and might compromise the primary care task. To increase compliance, the authors suggested focusing on the anaesthesia workflow, environmental cleaning, double gloving, disinfecting gloves, and separating contaminated from non-contaminated areas [[10]
,17
, 18
, 19
].The degree to which self-touching contributed to a large amount of HH opportunities is novel and noteworthy. Only a video-based HH investigation in intensive care and several face-touching studies have already highlighted this unconscious human behaviour [
[20]
,[21]
]. According to the ‘five moments’, the providers' bodies and apparel belong to the healthcare zone [[5]
]. Clothes might indeed be relevant for indirect pathogen transmission, as a recent review suggested [[22]
]. Studies have shown that nursing and physician attire can be contaminated, and bacteria can survive on textiles for up to 24 h [[23]
,[24]
]. Infectious risks of touching facial mucous membranes have been recognized [[21]
]. However, consistent HH before and after self-touching gestures seems unrealistic because of their unconscious nature and sheer frequency. Suppressive strategies should be avoided due to potential negative behavioural, cognitive, and neurophysiological effects [[21]
]. The qualitative analysis allowed us to identify ‘archetypical’ constellations for increased self-touching behaviour, including personal behaviour patterns. These patterns indicate that some individuals might contribute disproportionately to transmission risk, a fact rarely reported so far [[25]
].The present study found several factors independently associated with a slightly better HH adherence, namely senior physician status, drug administrator role, and opportunities before donning and after doffing gloves, whereas holding an object was independently associated with low HH adherence. Seniority was independently associated with higher adherence, as others have found, and was attributed to serving as a role model or professional routine [
[26]
,[27]
]. Drug administrators might be motivated by reports of bloodstream infections due to contaminated vascular access in anaesthesia [[28]
]. Our study registered many missed HH actions due to gloves being worn during the entire duration of HH opportunities. Gloves might induce a ‘safety bias’, ignoring that gloved hands act as vectors [[22]
,[29]
,[30]
]. Moreover, the high work pace makes glove changes challenging. Contrarily, however, HH adherence was higher when gloves were donned or doffed during the HH opportunity. Additionally, according to our qualitative observations, glove changes and HH seemed to be triggered by the start or end of a task sequence as an intrinsic behavioural cue. Another finding was that during a third of all HH opportunities, HCWs were holding objects, which inherently prevents HH action. Moreover, the numerous objects involved in anaesthesia induction, such as laryngoscopes, tape, masks, and patient documents represent themselves as potential vectors for transmission and make HH seem futile when touched repetitively. This confirms findings of prior studies in anaesthesia [[20]
,[31]
,[32]
].The WHO HH concept has been developed and adopted as universal guidance as to when cleaning hands in healthcare [
[6]
]. However, as witnessed by several studies, including ours, it appears impractical for anaesthesia induction in its current form – despite widespread application in this setting [31
, 32
, 33
]. This tension must be resolved. Our analysis reveals opportunities for system redesign using a human factors and ergonomics approach [[34]
,[35]
]. As we show, the reattribution of selected objects and surfaces to the patient zone would already reduce HH opportunities by almost half. This would involve for instance replacing tape rolls and systematically cleaning high-touch objects such as drawer handles, tourniquets, pens, and stethoscopes between patients and regularly changing attire. The practicality and implementation of such changes would have to be established in an iterative co-creation process involving providers and designers. The zone concept could be redesigned considering both the typical induction workflow and the intrinsic human HH behaviour. If done well, even accepting a moderately increased transmission risk would be overcompensated by an increased adherence, ultimately resulting in a higher system-level microbiological safety.The study has limitations. First, we did not differentiate the specific infectious risk level for each HH moment. Understanding these specific risks has been identified as an item on the HH research agenda [
[36]
]. Second, this was a single-centre, single-operating-theatre study. However, because of the standardized nature of anaesthesia induction, our findings most likely apply to this setting in general. Third, as in all observation studies, we cannot rule out a possible Hawthorne effect such that HCWs modified their behaviour in response to being observed. Fourth, the simplified version of ‘five moments’ might lead to an increased number of HH opportunities by including ‘before touching the patient's immediate environment’ in Moment 1. However, the simplified ‘four moments’ concept has been widely adopted, and, even without good microbiological evidence, it seems fair to assume that colonizing surfaces near the patient would lead to cross-contamination in this specific context.In conclusion, anaesthesia induction represents a high-paced, high-demand task environment posing a serious challenge to the strict application of the WHO HH concept. High cognitive load, the need to regularly use gloves and carry objects, and the fast sequence of HH determining hand-to-surface exposures, including the unconscious touching of the own clothes and skin, represent the main drivers for non-adherence to these internationally accepted HH rules. With this investigation, we were able to identify individual and system features that have been largely overlooked in the past. Future work can build on our findings to design a simpler pragmatic rule-set that would be better adapted to this work system. This would most likely lead to improved patient safety.
Acknowledgements
We are grateful to Y. Knill for coordinating the video recordings and G. Friedli for his help with the hand hygiene coding. Further we thank all HCWs and patients who took part in the study.
Author contributions
J.B.S. acquired and analysed data and wrote the manuscript. B.G. acquired the data, and revised the manuscript. H.S. supervised the study, analysed data, and revised the manuscript. All authors approved the final version of this manuscript.
Conflict of interest statement
J.B.S. is faculty for The Debriefing Academy, which runs debriefing courses for healthcare professionals. J.B.S. receives honorariums from PAEDSIM e.V. to teach simulation educator courses. H.S. received travel grants and/or honorary speakers from AstraZeneca, agfarm, Walker Projects, and Digital Economic Forum, all unrelated to the topic of this study.
Funding sources
This work was partially funded by the Swiss National Science Foundation [grant number P300P1_177695] and [grant number PCEFP1_203374].
Appendix A. Supplementary data
The following is the Supplementary data to this article.
- Multimedia component 1
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Article info
Publication history
Published online: March 09, 2023
Accepted:
March 7,
2023
Received:
December 15,
2022
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© 2023 The Author(s). Published by Elsevier Ltd on behalf of The Healthcare Infection Society.
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