In Denmark, capnography is routinely used in monitoring patients with artificial airways. Non-invasive capnography is occasionally used by prehospital providers, but not applied inside hospital walls. Multiple studies illustrate benefits from capnography in non-intubated patients. Non-invasive capnography may reveal altered ventilation in conditions such as opioid-induced respiratory depression and acute dyspnoea, during metabolic acidosis and among patients with seizures and cerebral damage. Implementation requires education, guidelines for inhospital use and financial investment.