Surgeon Personal Protection: An Underappreciated Benefit of Positive-pressure Exhaust Suits

Abstract

Background: Positive-pressure exhaust suits cost more than standard surgical gowns, and recent evidence suggests that they do not decrease infection risk. As a result, some hospitals and surgeons have abandoned positive-pressure exhaust suits in favor of less expensive alternatives. We propose that in addition to their original purpose of decreasing infection rates, positive-pressure exhaust suits may also improve personal protection for the surgeon and assistants, perhaps justifying their added costs.

Questions/purposes: (1) Do positive-pressure exhaust suits decrease exposure to particulate matter during TKA? (2) What areas covered by gowning systems are at risk of exposure to particulate matter?

Methods: Three surgical gowning systems were tested: (1) surgical gown, face mask, surgical skull cap, protective eyewear; (2) surgical gown, face mask, surgical protective hood, protective eyewear; and (3) positive-pressure exhaust suit. For each procedure, a cadaver knee was injected intraarticularly and intraosseously with a 5-µm fluorescent powder mixed with water (1 g/10 mL). After gowning in the standard sterile fashion, the primary surgeon and two assistants performed two TKAs with each gowning system for a total of six TKAs. After each procedure, three independent observers graded skin exposure of each surgical participant under ultraviolet light using a standardized scale from 0 (no exposure) to 4 (gross exposure). Statistical analysis was performed using Friedman's and Nemenyi tests. The interrater reliability for the independent observers was also calculated.

Results: The positive-pressure exhaust suits had less surgeon and assistant exposure compared with other systems (p < 0.001). The median overall exposure grade for each gowning system was 4 for System 1 (range, 3-4), 2.5 for System 2 (range, 2-3), and 0 for System 3 (range, 0-0). In pairwise comparisons between gowning systems, the positive-pressure exhaust suits had less exposure than gowning System 1 (difference of medians: 4, p < 0.001) and gowning System 2 (difference of medians: 2.5, p = 0.038). There was no difference found in exposure between Systems 1 and 2 (difference of medians: 1.5, p = 0.330). When gowning Systems 1 and 2 were removed, particulate matter was found in places that were covered such as the surgeon's beard, lips, inside the nostrils, behind the protective eyewear around the surgeon's eye, and in both eyebrows and eyelashes.

Conclusions: The positive-pressure exhaust suits provided greater personal protection with each procedure than the other two gowning systems.

Clinical relevance: With conventional gowns, particulate matter was found in the surgeon's eyelashes, under the face mask around the mouth, and inside the nostrils. Despite recent evidence that certain types of positive-pressure exhaust suits may not decrease infection, there is a clear benefit of surgeon protection from potentially infectious and harmful patient substances. Despite their added costs, hospitals and surgeons should weigh this protective benefit when considering the use of positive-pressure exhaust suits.

Fig. 1A-F

Front and side views of each tested gowning system are shown, including the conventional Halyard ULTRA Surgical gown (Halyard Health, Alpharetta, GA, USA), which includes a surgical skull cap, surgical face mask, and protective eyewear (A-B); a Halyard ULTRA surgical gown with a surgical protective hood, surgical face mask, and protective eyewear (Halyard Health; C-D); and a Stryker one-piece toga (Stryker, Kalamazoo, MI, USA; E-F).

Fig. 2A-B

To simulate patient particulate matter, a 5-μm fluorescent powder was mixed with water and was injected intraarticularly into the knee (A) and intraosseously into the proximal tibia (B).

Fig. 3

Two standardized, simulated TKAs were performed for each gowning system for a total of six procedures.

Fig. 4A-D

Particulate matter exposure encountered by surgical participants while wearing each gowning system shown here, including side views (A-B) and front view (C) of conventional gowning systems, and front view of the positive-pressure exhaust suit providing complete surgical participant protection (D).

Fig. 5A-B

Views of particulate matter exposure encountered by surgical participants that was seen after the gowning system was removed are shown, including inside the surgeon’s nostrils (A) and on both the eyebrow and eyelashes (B).