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Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 25, No 18S (June 20 Supplement), 2007: 9031
© 2007 American Society of Clinical Oncology
Continuous intravenous lidocaine controls abdominal pain secondary to peritoneal carcinomatosis as a consequence of diffusion into ascites
T. Tanaka,
R. Tsukui,
S. Okano,
M. Tsuchiya,
K. Obokata,
T. Ogawa,
T. Abe,
T. Ikeya and
M. Miyasaki
Maebashi Red Cross Hospital, Maebashi, Gunma, Japan
9031
Background: Our team reported at the 42nd ASCO meeting that continuous, low-dose intravenous (IV) lidocaine is an effective method for pain relief in terminal patients with peritoneal carcinomatosis. Our aim was to explore the mechanism by which abdominal pain of terminally-ill patients with peritoneal carcinomatosis was improved by continuous IV lidocaine. Methods: 48 patients with peritoneal carcinomatosis due to GI (46) and GYN (2) malignancies were administered lidocaine at low-doses (0.4 and/or 0.8mg/kg- h) for >24 hours, because opiates, NSAIDs, and other adjuvants were ineffective in relieving their abdominal pain. Pain (faces rating scale; 0-no pain, 5-worst pain), oral intake, side effects, and activities of daily life were quantified. Two days after beginning lidocaine, ascites was sampled to measure ascitic concentration of lidocaine, tumor markers and cytology. Results: Mean age (±SE) was 60±2. The volume of ascites was estimated to be 2,700±400ml by the ultrasound 5 points methodology. Abdominal symptoms improved in 1.5±0.2days after beginning lidocaine, and the pain scale decreased from 1.9±0.2 to 0.5±0.1; p<0.001; 75% of patients had improvement in pain of whom 78% had complete relief of pain. Oral intake increased from 18% to 49% of baseline (p<0.001), and 67% in those with improvement in pain had an increased volume of oral intake. There were no obvious differences in response to 0.4 and 0.8 mg/kg-h in patients receiving both doses. Serum concentrations of lidocaine at 0.4 and 0.8 mg/kg-h were 1.7±0.2 and 3.2±0.2 µg/ml, respectively; lidocaine concentrations in the ascites were 1.2±0.2 and 2.1±0.2 µg/ml. No patient complained of pain at the time of peritoneal puncture. Side effects included bradycardia of <60 beats per minutes (3 patients). The duration of lidocaine administration was 23±3 days; 43% of patients were able to be discharged home for end-of-life care, with parenteral nutrition and continuation of lidocaine administration or oral mexiletine (300450 mg/day) for adjuvant analgesia. Conclusions: Lidocaine diffuses into ascites and almost equilibrates with serum concentrations acting as a peritoneal anesthesia which, as a result, controls abdominal pain in patients with peritoneal carcinomatosis.
No significant financial relationships to disclose.
Abstract presentation from the 2007 ASCO Annual Meeting
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