Wednesday, September 30, 2009

NEJM Perspective: Respiratory Protection For HCWs

 

 

# 3788

 

While the debate over what constitutes suitable protection for HCWs (Health Care Workers) when dealing with influenza patients continues, the IOM recently came out with their analysis and they came down decidedly on the side of N95 respirators instead of surgical masks.

 

The complete 68 page IOM report can be downloaded by clicking the graphic below.  It is free, although you’ll be asked for your email address.

 

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The CDC’s current recommendations are also for N95 respirators, although they are `reviewing the data’.  Many hospitals continue to use surgical masks instead of N95s, despite the CDC’s recommendation.  

 

Critics of N95s point out that they can be uncomfortable to wear for extended periods of time, and that they are in short supply.   Many HCWs, however, question whether the reluctance of some facilities to embrace N95s for influenza infection protection has had more to do with their cost than with their availability or comfort.

 

Today the NEJM has a Perspective article which reviews the IOM report data, and comes down in favor of N95’s.   I’ve provided some of the more pertinent passages below, but follow the link to read it in its entirety.


Published at www.nejm.org September 30, 2009 (10.1056/NEJMp0908437)
Novel H1N1 Influenza and Respiratory Protection for Health Care Workers


Kenneth I. Shine, M.D., Bonnie Rogers, Dr.P.H., R.N., and Lewis R. Goldfrank, M.D.


(EXCERPTS)

Health care workers have long relied heavily on surgical masks to provide protection against influenza and other infections. Yet there are no convincing scientific data that support the effectiveness of masks for respiratory protection.

 

The masks we use were not designed for such purposes, and when tested, they have proved to vary widely in filtration capability, allowing penetration of aerosol particles ranging from 4 to 90%.

 

These masks — which are open on the sides, top, and bottom — may be useful in source control when worn by a patient, but even then, there is evidence that material escapes around the mask's margins after a sneeze or forcible cough.

 

By contrast, respirators cover the nose and mouth (at a minimum) and are designed to purify the air that the wearer breathes in, either by filtering it or by providing an independent air supply.

 

It has been demonstrated that N95 respirators filter out 95 to 99% of relevant aerosol particles. Although these respirators function best when they are individually fitted, unfitted respirators do have efficacy. The available evidence indicates that the tight fit and enhanced filtration capacity of these devices offer better protection against aerosol particles than do surgical masks.

 

Until more data are available, the committee recommends that clinicians reach for the N95 respirator when confronting patients with influenza-like illnesses, particularly in enclosed spaces.

 

 

Authorities have been warning that a pandemic was likely since 2005, and  nearly 18 months ago OSHA  published a recommended stockpiling guideline for Health Care facilities, where they estimated that every nurse with direct patient contact would need roughly 480 - N95 respirators for a 12 week pandemic wave.

 

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Despite this guidance, many facilities failed to purchase the OSHA recommended stockpile of PPEs (Personal Protective Equipment), and so N95s are reportedly in short supply at many hospitals.  

 

This shortage is being used as a justification by some hospitals that are issuing surgical masks to HCWs caring for flu patients, instead of N95 respirators.

 

And in the absence of N95s, admittedly that may be the only viable option.

 

We are indeed fortunate that we are dealing with a milder swine flu virus, and not the much deadlier bird flu virus. But that was a matter of luck, nothing more. 

 

And we are not out of the woods yet, as a more virulent virus could still emerge down the road.

 


The failure of many institutions to prepare for an event that public health officials have been warning about for nearly 4 years is hard to fathom.  

 

No doubt they had reasons that sounded reasonable to them at the time.

 

Whether those reasons will sound as reasonable to their employees – some of whom may be asked to work around flu patients this winter without the protection of N95 respirators - remains to be seen.