ObjectiveThe capnometry values during resuscitation are an evolutive predictor of kidneys obtained from uncontrolled non-heart beating donors. DesignThe study comprised a retrospective onset cohort of 37 non-heart beating donors and a validation cohort of 55 transplanted kidneys in the period 2013–2017. ScopeThe population served by the emergency service and referred to Hospital Universitario Doce de Octubre (Madrid, Spain) as potential uncontrolled non-heart beating donors. PatientsA total of 55 renal transplant patients subjected to hemodialysis and with grafts from uncontrolled non-heart beating donors. InterventionsCapnometry and capnography measurements in potential uncontrolled non-heart beating donors. VariablesCapnometry values recorded initially and at transfer in hospital for comparison with the viability of the extracted kidneys; renal failure and delayed renal function. ResultsA total of 55 out of 74 extracted kidneys were transplanted (74.3%). The rest were ruled out due to poor perfusion or signs of ischemia. An association was observed (p = 0.016) between the capnometry values during resuscitation in the grafted kidneys (µ = 22.8 mmHg) and in the kidneys discarded for transplantation (µ = 17.35 mmHg). ConclusionsCapnometry during resuscitation serves as a marker to be taken into account in relation to the viability of the transplanted organs in uncontrolled non-heart beating donors.