Pre-hospital blood gas analysis – an observational study on the widespread introduction of point-of-care diagnostics in air ambulance services in Germany

In the chaotic minutes following a serious accident or a sudden medical collapse, time is the most precious resource. Emergency teams racing to the scene face a difficult reality: they must make life-or-death decisions without the full suite of laboratory tools available in a hospital. For decades, the standard approach has been to stabilize the patient and transport them quickly, relying on physical signs and basic monitoring to guide treatment. However, a specific type of test, known as a blood gas analysis, offers a way to peer directly into the body's chemical balance. This test measures how well the blood is carrying oxygen, how effectively it is removing carbon dioxide, and whether the body's internal acidity is out of balance. It also checks the levels of vital minerals and energy markers. While this test is a routine part of care inside hospitals, bringing it to the roadside or into a helicopter has been rare, largely due to the complexity of the equipment and the harsh conditions of emergency work. The question facing modern emergency medicine is whether having this chemical snapshot immediately available changes the outcome for patients, or if it remains a tool that is too difficult to use effectively outside the clinic.

A large-scale study conducted by the German Air Rescue organization, DRF Luftrettung, sought to answer this question by looking at what actually happened after they equipped their entire fleet of rescue helicopters with portable blood gas analyzers. Over the course of a single year, from January to December 2025, the researchers examined the records of more than 30,000 missions. They focused specifically on the primary missions, which are the urgent calls to treat patients at the scene, totaling over 22,000 flights. The goal was not to test a new theory in a controlled setting, but to observe how medical crews used this new technology in the real world and whether the information they gathered led to different treatment decisions. The study covered 29 different air bases across Germany, providing a broad view of how this diagnostic tool was integrated into daily emergency operations.

The results revealed that while the technology was available, its use was surprisingly selective. Out of the more than 22,000 primary missions, the crews performed a blood gas test in only about 523 cases, representing roughly 2.3 percent of all flights. This low frequency was not due to a lack of equipment or training; the crews were highly skilled and the devices were available on every helicopter. Instead, the data showed that the decision to use the test was driven by the severity of the patient's condition. The test was used most often when a patient was undergoing resuscitation outside the hospital, a situation where the medical team was trying to restart a stopped heart. In these critical moments, the test was performed in nearly 10 percent of cases. It was also used more frequently for patients with severe head injuries or multiple trauma, though the rates for these groups were lower than for cardiac arrests. The study found that the more critical the patient appeared, the more likely the crew was to reach for the analyzer.

When the crews did perform the test, the information often changed how they treated the patient. In the group of patients undergoing resuscitation, the test results led to a specific change in treatment in more than 80 percent of cases. The most common adjustments involved changing the drugs being administered or altering the way the patient was being ventilated. For example, the test frequently revealed that the blood was dangerously acidic or that levels of potassium were too high, prompting immediate medical intervention to correct these imbalances. In cases of severe trauma, the test results influenced drug therapy and breathing support in about two-thirds of the instances where it was used. However, for patients with neurological emergencies, such as strokes or unexplained loss of consciousness, the test led to a change in treatment less often, suggesting that the immediate chemical clues were less likely to dictate the next step for these specific conditions compared to cardiac or trauma cases.

The chemical data itself painted a stark picture of the patients' conditions. In the resuscitation group, the average blood acidity was extremely low, far outside the normal range, and levels of lactate, a marker of tissue stress, were dangerously high. These values confirmed that the patients were in a state of severe physiological crisis. The study also noted significant differences in how often the test was used across different regions. Some air bases used the device in nearly 15 percent of their missions, while others rarely used it at all, despite having the same equipment and training. The researchers suggested that this variation might be due to how well the new technology was adopted by the local teams, rather than differences in the types of patients they treated.

Ultimately, the study concludes that having a blood gas analyzer in a helicopter is a valuable tool, but it is not a routine check for every patient. The data suggests that the test is most effective when used for the sickest patients, particularly those whose hearts have stopped or who have suffered severe physical trauma. In these situations, the test provides critical information that allows crews to adjust their treatment before the patient even reaches the hospital. The researchers emphasize that while the tool is powerful, its full potential depends on better integration into standard procedures and more targeted training for crews to ensure they know exactly when and how to use it. The study does not claim that the test cures patients on its own, but rather that it provides a vital piece of the puzzle that helps medical teams make more informed decisions during the most critical moments of an emergency.