A 46-year-old female aid worker with no significant past medical history fell ill with fever and general malaise in Bangui, Central African Republic. At presentation to a local outpatient clinic, she suffered from headaches, congestion, mild cough, fever, and chills. Blood counts, coagulation profile, D-Dimers, blood electrolytes, liver function tests, renal parameters, uric acid, glycemia, cholesterol and triglycerides were all normal. A lateral flow SARS-CoV2 antigen test was initially reported positive, however, this test result was never confirmed or presented in writing to the assistance company handling the case. Over the following week, her symptoms did not improve. On day four, the hospital reported positive results from malaria testing and blood smears.
In view of the limited local diagnostic and therapeutic options, an emergency evacuation by air ambulance to London, UK, was rapidly organised and activated. A Unicair Learjet 45 was dispatched from Cologne, Germany, with a collapsible Portable Medical Isolation Unit (PMIU) in the external cargo hold. A Roche SARS-CoV2 Rapid Antigen Test yielded positive results on the evening of arrival and again the next day. The flight crew unloaded, assembled and leak tested the PMIU. The medical crew, still in full PPE, loaded the patient from this side and after securing all lines, tubes and monitoring cables. Transport to London was uneventful with a stable patient and a brief refueling stop.
Point-of-care (PoC) testing with lateral flow antigen tests has been rapidly developed. If the specimens are collected by well-trained medical personnel using a deep naso-pharyngeal swap, these tests offer excellent positive and negative predictive values. PoC PCR testing for SARS-CoV-2 has also been developed and can now be performed by the air ambulance crew, with results becoming available within 30 minutes. If the air ambulance is staffed with a physician, this professional can issue an official medically verified test certificate, guaranteeing accurate execution and truthful reporting of results.
Since a positive test is one possible outcome even in a patient with little to no respiratory symptoms and complete vaccination status, a protocol on how to handle patients with a positive test result needs to accompany all PoC testing and, in the absence of clear guidance by a European regulatory body, is most likely informed by the regulations of the country in which the aircraft is registered.
Effective isolation with the sole use of PPE (FFP2 masks by patient and medical team and social distancing) is difficult to facilitate in a small aircraft cabin and further hampered by the fact that almost all small air ambulance aircraft have a backto-front airflow and the limitations of the flight crew to continuously wear FFP2 masks for safety reasons (hindering a pilot’s ability to rapidly secure their oxygen mask in the scenario of an explosive cabin decompression).
There are several risks in transporting a moderately to severely ill patient in a PMIU. We identified the main challenges as being limited access to the patient and reduced manual dexterity when delivering care through the porthole gloves. Meticulous preparation of equipment and patient using standardised protocols and checklists, the use of wireless technology to transmit patient data from the inside of the PMIU to the outside, and training and simulation sessions with transport teams can mitigate some, but not all the transport-specific risks. Careful consideration of the individual risk-benefit balance resulted in most air ambulance operators (including Unicair) deciding to transport ventilated patients without a PMIU in an open cabin, relying on a closed ventilation circuit with HEPA filters, closed suction systems and PPE for the medical team.
Uncertain times require flexible mission profiles and highly adaptive solutions to guarantee optimal safety for patients and crew. PoC testing capacities and on-demand isolation options allow for a tailored risk-benefit assessment at the scene and underscore the importance of close collaboration between assistance alarm centres and air ambulance operators. Furthermore, the ability to provide on-demand PMIU capacities en-route can prevent significant financial losses for the insurer by reducing the number of failed missions due to unexpected changes in infection status of the patient.