We report an open, uncontrolled study designed to assess the effects of subcutaneous (SC)
morphine on
dyspnea of terminal
cancer. Twenty patients with
dyspnea caused by restrictive
respiratory failure received an SC dose of
morphine of 5 mg (5 patients who were not receiving
narcotics), or equivalent to 2.5 times their regular dose (15 patients who were receiving
narcotics for
pain).
Dyspnea (D) and
pain (15 cases) were measured before the dose and every 15 min for 150 min after the injection using a visual analog scale 0-100. Respiratory rate (RR), respiratory effort (RE) (score 1-6), arterial saturation of O2 (SO2) and end-tidal PACO2 were determined before and 45 min after SC
morphine. D, RR, RE, SO2, and PACO2 were 68 +/- 32, 32 +/- 7; 3.5 +/- 1.8, 87 +/- 10, and 31 +/- 12, respectively, before SC
morphine, and 34 +/- 25 (P less than 0.001), 31 +/- 9 (P:NS), 3.2 +/- 1.9 (P:NS), 86 +/- 11 (P:NS), and 33 +/- 9 (P:NS), respectively, 45 min after SC
morphine. Nineteen of 20 patients (95%) reported improved
dyspnea after
morphine. We conclude that
morphine appears to improve
dyspnea without causing a significant deterioration in respiratory function in terminal
cancer patients. Double-blind placebo controlled studies are needed in this population.