Airway management by physicians wearing anti-chemical warfare gear: comparison between laryngeal mask airway and endotracheal intubation:

Staff perceptions of military chemical-biological-radiological-nuclear (CBRN) air-purifying masks during a simulated clinical task in the context of SARS-CoV-2

Air-purifying full-face masks, such as military chemical-biological-radiological-nuclear masks, might offer superior protection against severe acute respiratory syndrome coronavirus 2 compared to disposable polypropylene P2 or N95 masks. In addition, disposable masks are in short supply, while military chemical-biological-radiological-nuclear masks can be disinfected then reused. It is unknown whether such masks might be appropriate for civilians with minimal training in their use. Accordingly, we compared the Australian Defence Force in-service chemical-biological-radiological-nuclear Low Burden Mask (AirBoss Defense, Newmarket, Canada) with polypropylene N95 masks and non-occlusive glasses worn during simulated tasks performed by civilian clinicians in an Australian tertiary referral hospital intensive care unit. After brief training in the use of the Low Burden Mask, participants undertook a simulated cardiac arrest scenario. Previous training with polypropylene N95 masks had been provided. Evaluation of 10 characteristics of each mask type were recorded, and time to mask application was assessed. Thirty-three participants tested the Low Burden Mask, and 28 evaluated polypropylene N95 masks and glasses. The Low Burden Mask was donned more quickly: mean time 7.0 (standard deviation 2.1) versus 18.3 (standard deviation 6.7) seconds; P = 0.0076. The Low Burden Mask was rated significantly higher in eight of the 10 assessed criteria, including ease of donning, comfort (initially and over a prolonged period), fogging, seal, safety while removing, confidence in protection, and overall. Visibility and communication ability were rated equally highly for both systems. We conclude that this air-purifying full-face mask is acceptable to clinicians in a civilian intensive care unit. It enhances staff confidence, reduces waste, and is likely to be a lower logistical burden during a prolonged pandemic. Formal testing of effectiveness is warranted.

Systematic review and meta-analysis comparing ventilatory support in chemical, biological and radiological emergencies

Objective:

to compare the mean development time of the techniques of direct laryngoscopy and insertion of supraglottic devices; and to evaluate the success rate in the first attempt of these techniques, considering health professionals wearing specific personal protective equipment (waterproof overalls; gloves; boots; eye protection; mask).

Method:

meta-analysis with studies from LILACS, MEDLINE, CINAHL, Cochrane, Scopus and Web of Science. The keywords were the following: personal protective equipment; airway management; intubation; laryngeal masks.

Results:

in the “reduction of the time of the procedures” outcome, the general analysis of the supraglottic devices in comparison with the orotracheal tube initially presented high heterogeneity of the data (I²= 97%). Subgroup analysis had an impact on reducing heterogeneity among the data. The “laryngeal mask as a guide for orotracheal intubation” subgroup showed moderate heterogeneity (I²= 74%). The “2^ndgeneration supraglottic devices” subgroup showed homogeneity (I²= 0%). All the meta-analyses favored supraglottic devices. In the “success in the first attempt” outcome, moderate homogeneity was found (I²= 52%), showing a higher proportion of correct answers for supraglottic devices.

Conclusion:

in the context of chemical, biological or radiological disaster, the insertion of the supraglottic device proved to be faster and more likely to be successful by health professionals. PROSPERO record (CRD42019136139).

Impact of Clinician Personal Protective Equipment on Medical Device Use During Public Health Emergency: A Review

The aim of this systematic review is to evaluate the impact of personal protective equipment (PPE) on medical device use during public health emergency responses. We conducted a systematic literature search of peer-reviewed journals in PubMed, Web of Science, and EBSCO databases. Twenty-nine of 92 articles published between 1984 and 2015 met the inclusion criteria for the review. Although many medical device use impacts were reported, they predominantly fell into 3 categories: airway management, drug administration, and diagnostics and monitoring. Chemical, biological, radiological, and nuclear (CBRN)-PPE increased completion times for emergency clinical procedures by as much as 130% and first attempt failure rates by 35% (anesthetist) versus 55% (non-anesthetist). Effects of CBRN-PPE use depend on device, CBRN-PPE level, and clinician experience and training. Continuous clinical training of responders in CBRN-PPE and device modifications can improve safety and effectiveness of medical device use during public health emergency response.

Intubation performance using different laryngoscopes while wearing chemical protective equipment: a manikin study

OBJECTIVES

This study aimed to compare visualisation of the vocal cords and performance of intubation by anaesthetists using four different laryngoscopes while wearing full chemical protective equipment.

SETTING

Medical simulation center of a university hospital, department of anaesthesiology.

PARTICIPANTS

42 anaesthetists (15 females and 27 males) completed the trial. The participants were grouped according to their professional education as anaesthesiology residents with experience of <2 years or <5 years, or as anaesthesiology specialists with experience of >5 years.

INTERVENTIONS

In a manikin scenario, participants performed endotracheal intubations with four different direct and indirect laryngoscopes (Macintosh (MAC), Airtraq (ATQ), Glidescope (GLS) and AP Advance (APA)), while wearing chemical protective gear, including a body suit, rubber gloves, a fire helmet and breathing apparatus.

PRIMARY AND SECONDARY OUTCOME MEASURES

With respect to the manikin, setting time to complete 'endotracheal intubation' was defined as primary end point. Glottis visualisation (according to the Cormack-Lehane score (CLS) and impairments caused by the protective equipment, were defined as secondary outcome measures.

RESULTS

The times to tracheal intubation were calculated using the MAC (31.4 s; 95% CI 26.6 to 36.8), ATQ (37.1 s; 95% CI 28.3 to 45.9), GLS (35.4 s; 95% CI 28.7 to 42.1) and APA (23.6 s; 95% CI 19.1 to 28.1), respectively. Intubation with the APA was significantly faster than with all the other devices examined among the total study population (p<0.05). A significant improvement in visualisation of the vocal cords was reported for the APA compared with the GLS.

CONCLUSIONS

Despite the restrictions caused by the equipment, the anaesthetists intubated the manikin successfully within adequate time. The APA outperformed the other devices in the time to intubation, and it has been evaluated as an easily manageable device for anaesthetists with varying degrees of experience (low to high), providing good visualisation in scenarios that require the use of chemical protective equipment.

Does position of the patient adversely affect successful intubation whilst wearing CBRN-PPE?

INTRODUCTION

Following a CBRN incident attending medical personnel will be required to instigate life saving airway interventions whilst wearing CBRN-PPE. CBRN-PPE is known to adversely affect fine motor skill but little is known about whether the position of the patient compounds this problem.

METHODS

Seventy-five clinicians were recruited and performed intubation and insertion of a LMA in to a manikin whilst wearing CBRN-PPE. Both skills were completed twice with the manikin positioned on a bench and once on the floor. Following completion of the study 25 participants (a minimum of 2 participants from each professional group) were interviewed to ascertain their experiences. The recruitment of a non-homogenous group allowed for subgroup analysis with regards the potential impact of professional background on skill performance.

RESULTS

9.33% first attempts at intubation at waist height ended in failure but this reduced to 4% on the second attempt. This improvement was reversed with the manikin on the floor where the failure rate was 26.67%. Intubation on the floor took significantly longer to perform, being 45.9 s slower than the first attempt at intubation in the optimal position [95% CI (30.7 s, 61.1 s); p<0.001] and 62.4 s longer than the second [95% CI (48.4 s, 76.3 s); p<0.001]. LMA insertion was successful at all attempts, regardless of the manikins position. LMA placement on the floor was no slower than the second attempt at waist height (p=0.231) and faster than the first attempt at waist height (by 4.8 s [95% CI (3.4 s, 6.1 s); p<0.001]). Anaesthetists were consistently the fastest at performing all airway skills regardless of the position of the manikin but previous exposure to wearing CBRN-PPE had no statistically significant impact on skill performance. All 25 clinicians interviewed had difficulty in viewing the larynx with the manikin positioned on the floor regardless of being an experienced 'on floor' intubator with the movement of the CBRN-PPE hood being the principle reason. This is in contrast to only three participants noting issues with vision whilst standing-up.

CONCLUSION

the position of the patient is likely to be an independent factor when choosing to either intubate or insert a LMA whilst wearing the current NHS CBRN-PPE.