Resumen:
A bibliographic review found three randomized double-blinded placebo-controlled studies and five prospective studies, six of which showed that opioids significantly relieve dyspnea (P<0.001). The use of morphine for symptomatic relief does not significantly change the level of saturation of oxygen in the blood. In addition, the functional studies do not indicate that the use of opioids for dyspnea relief causes high CO2 levels in blood (P=0.05). The opioids used for treating dyspnea do not significantly compromise respiratory function; they are safe and effective.