The COVID-19 pandemic disrupted the world in 2020 by spreading at unprecedented rates and causing tens of thousands of fatalities within a few months. The number of deaths dramatically increased in regions where the number of patients in need of hospital care exceeded the availability of care. Many COVID-19 patients experience Acute Respiratory Distress Syndrome (ARDS), a condition that can be treated with mechanical ventilation. In response to the need for mechanical ventilators, designed and tested an emergency ventilator (EV) that can control a patient’s peak inspiratory pressure (PIP) and breathing rate, while keeping a positive end expiratory pressure (PEEP). This article describes the rapid design, prototyping, and testing of the EV. The development process was enabled by rapid design iterations using additive manufacturing (AM). In the initial design phase, iterations between design, AM, and testing enabled a working prototype within one week. The designs of the 16 different components of the ventilator were locked by additively manufacturing and testing a total of 283 parts having parametrically varied dimensions. In the second stage, AM was used to produce 75 functional prototypes to support engineering evaluation and animal testing. The devices were tested over more than two million cycles. We also developed an electronic monitoring system and with automatic alarm to provide for safe operation, along with training materials and user guides. The final designs are available online under a free license. The designs have been transferred to more than 70 organizations in 15 countries. This project demonstrates the potential for ultra-fast product design, engineering, and testing of medical devices needed for COVID-19 emergency response.

Sanitation guidelines for animal research facilities state that disinfection is achieved by application of high-temperature water (143 to 180 °F [62 to 82 °C]) or detergents and disinfectants. However, these guidelines are based on requirements for pasteurization, which may be unnecessarily stringent for the sanitation of nonfood items and do not address the theoretical sanitation potential of water at temperatures below 143 °F (62 °C). Recent literature indicates that water temperatures below 143 °F (62 °C) can also provide effective sanitation. In this study, we compared cagewash cycles at low (100 °F [38 °C] and 120 °F [49 °C]) and high (standard) (180 °F [82 °C]) temperatures and evaluated sanitation efficacy by using ATP swabs and RODAC plates. Low-temperature loads were washed either with or without prior treatment of a chemical disinfectant (10% bleach). The 100 °F (38 °C) cycle was not sufficient for sanitization without bleach pretreatment. However, the 120 °F (49 °C) cycle effectively sanitized cages without bleach pretreatment. Validation of effective sanitation at a lower water temperature (120 °F [49 °C]) can improve cagewash logistics and reduce costs as compared with standard (180 °F [82 °C]) high-temperature cycles.

Intrapleural injections can be used in mice to deliver therapeutic and diagnostic agents and to model human disease processes (for example, pleural fluid accumulation, malignant pleural disease, and lung cancers). In the context of establishing cancer models, minimally invasive methods of intrapleural injection are desirable because inflammation at the injection site can have a major impact on tumor growth and progression. Common approaches for intrapleural injection include surgical exposure of the thoracic wall or the diaphragm prior to injection; however, these invasive procedures require tissue dissection that triggers an undesirable inflammatory response and increases the risk of pneumothorax. While nonsurgical procedures can minimize this concern, ‘blind’ injections may lead to off target inoculation. In this study, we hypothesized that a minimally invasive transthoracic approach (MI-TT) would produce a tumor distribution and burden similar to that of a surgical transabdominal approach (SX-TA). Prior to performing the procedures on live mice, surgeons were trained using cadavers and terminal procedures. Then a total of 14 nude mice (female, 4 to 6 wk old) were injected with 50 μL (5 million) A549-Luc2 human cancer cells either using the MI-TT (n = 8) or SX-TA (n = 6) approach under carprofen analgesia and isoflurane anesthesia. Our results indicate that with training, a minimally invasive transthoracic approach for intrapleural injection provides more consistent tumor placement and a greater tumor burden than does the surgical method. However, additional studies are necessary to confirm anatomic placement and characterize tumor profiles.

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