Is secondary chemical exposure of hospital personnel of clinical importance?

INTRODUCTION

There is increasing concern among hospital personnel about potential secondary exposure when treating chemically contaminated patients.

OBJECTIVE

To assess which circumstances and chemicals require the use of Level C Personal Protective Equipment (chemical splash suit and air-purifying respirator), to prevent secondary contamination of hospital personnel treating a chemically contaminated patient.

METHODS

The US National Library of Medicine PubMed database was searched for the years 1985 to 2020 utilizing combinations of relevant search terms. This yielded 557 papers which were reviewed by title and abstract. After excluding papers on biological or radiological agents, or those not related to hospital personnel, 38 papers on chemicals remained. After a full-text review, 13 papers without an in-depth discussion on the risk for secondary contamination were omitted, leaving 25 papers for review. The references of these papers were searched and this yielded another seven additional citations, bringing the total to 32 papers.

INCIDENCE OF SECONDARY TOXICITY

Secondary toxicity in hospital personnel is rare: a large-scale inventory of 120,000 chemical incidents identified only nine cases, an occurrence of 0.0075%.

SKIN CONTACT AS A SECONDARY EXPOSURE ROUTE

Skin exposure is rare under normal hygienic working conditions, reflected by the very small number of cases reported in the literature: two cases with corrosive effects due to unprotected contact and one case of presumed skin absorption.

INHALATION AS A SECONDARY EXPOSURE ROUTE

Most case reports described secondary toxicity as a result of inhalation. The chemicals involved were irritating solid particles (capsaicin spray/CS), toxic gases formed in the stomach of patients (arsine/hydrazoic acid/phosphine) and vapours from volatile liquids (solvents).

FEATURES OF SECONDARY TOXICITY

Reported symptoms after secondary inhalation were generally mild and reversible (mostly irritation of eyes and respiratory tract, nausea, headache, dizziness/light-headedness) and did not require treatment. In many cases, special circumstances increased exposure: treatment/decontamination of multiple patients, regurgitation of the chemical agent from the stomach, or inadequate room ventilation.

USE OF MORE THAN STANDARD PERSONAL PROTECTIVE EQUIPMENT

Normal hygienic precautions prevent direct skin contact from exposure to common chemical agents. When solid particle contamination is extensive, a mask and eye protection should be applied. Splash proof outer clothing (splash suit) and eye protection is preferred if (partial) wet decontamination is performed on single patients. Adequate ventilation, careful removal of clothing in case of solid particles contamination and adequate disposal of gastric content reduces exposure. Hospital staff can be rotated if symptoms occur, which can be odour-mediated. The use of more elaborate personal protective equipment with an air-purifying respirator (Level C) is only necessary in exceptional cases of contamination with highly toxic volatile chemicals (e.g., sarin). It should also be considered when decontaminating a large number of patients.

CONCLUSIONS

The risk of secondary contamination and subsequent toxicity in hospital personnel decontaminating or treating chemically contaminated patients is small. Normal hygienic precautions (gloves and water-resistant gown) will adequately protect hospital staff when treating the majority of chemically contaminated patients. More extensive protection is only necessary infrequently and there is no reason to delay critical care, even if more elaborate protection is not immediately available.