key: cord-0898454-qfnqxgio
authors: Fox, Thomas H.; Silverblatt, Michael; Lacour, Alisha; deBoisblanc, Bennett P.
title: Negative Pressure Tent to Reduce Exposure of Health Care Workers to SARS CoV-2 During Aerosol Generating Respiratory Therapies
date: 2020-05-23
journal: Chest
DOI: 10.1016/j.chest.2020.04.070
sha: bc0897ab07b13f62e1a3987c569a5630d61a512c
doc_id: 898454
cord_uid: qfnqxgio

nan

Many patients admitted with COVID-19 pneumonia could benefit from high-flow nasal oxygen or noninvasive ventilation to address hypoxemia and/or work of breathing, but the use of these modalities has been associated with transmission of infection to healthcare workers 1 . Here we describe the creation of a simple negative pressure tent that can be placed over individual patients being treated anywhere within a hospital where wall suction is available. These tents are similar in appearance to the oxygen tents that were commonly used in the late 19th and early 20th centuries but instead of filling them with oxygen, wall suction is utilized to create negative pressure to remove aerosols generated within the tent. They are inexpensive to manufacture (~$100 US), easy to build on site, are highly scalable to meet the demands of individual institutions, and easily slide under the mattress of most hospital beds. In this configuration we measured in excess of 22 air changes per hour which exceeds the CDC recommendation of 12 air changes per hour for negative pressure isolation rooms. This simple design can maintain negative pressure with oxygen flow rates of over 60 L/min entering the tent. Healthcare workers wearing PPE can lift the edge of the tent to provide care without exposing their faces. Updraft nebulizer aerosol tests and cough tests utilizing florescent powder demonstrated no visible contamination outside of the tent. During simulations there was no measurable accumulation of CO2 within the tent. Fire hazards are always a concern when using medical oxygen, however oxygen concentrations within the tent never exceeded 43% using the simulated high flow devices at 60 L/min. The schematics and additional photographs and videos of these isolation tents can be found in the online supplement, which is linked below. Modification of this design to fit the table dimensions of special procedure suites and operating rooms is easily accomplished. We feel that this simple design is an inexpensive, rapidly deployable, and practical method to improve healthcare worker safety during the COVID-19 pandemic.

Link to online supplement: https://docs.google.com/document/d/1nDSpBCf2cU6lZVF09Egmwee2a5BpBAuVDMn0pkp9mE E/edit?usp=sharing

Aerosol generating procedures and risk of transmission of acute respiratory infections to healthcare workers: a systematic review

Figure: Negative pressure tent deployed in a simulated non-negative pressure hospital room