Fig. 1From: A report of three cancer patients on opioid analgesia receiving spinal anesthesia: abrupt pain elimination without respiratory depressiona Magnetic resonance imaging of the spine taken 8 months before the surgery showing multiple bone metastasis of the rectal cancer. b Compressed figure of capnography monitored during the surgery. Left and right axes show end-tidal CO2 and respiratory rate, respectivelyBack to article page