Anesth Analg 2008; 107:325-332
© 2008 International Anesthesia Research Society
doi: 10.1213/ane.0b013e3181770f55
REGIONAL ANESTHESIA
Long-Term Survival After Colon Cancer Surgery: A Variation Associated with Choice of Anesthesia
Rose Christopherson, MD, PhD*,
Kenneth E. James, PhD ,
Mara Tableman, PhD ,
Prudence Marshall, MS , and
Frank E. Johnson, MD, FACS||
From the *Anesthesiology Service, VA Medical Center and Department of Anesthesiology, OR Health and Science University, Portland, OR; Department of Public Health and Preventive Medicine, OR Health and Science University, Portland, OR; Department of Mathematics and Statistics, Portland State University and Department of Public Health and Preventive Medicine, OR Health and Science University, Portland, OR; Anesthesiology Service, VA Medical Center, Portland, OR; and ||Surgical Service, VA Medical Center and Department of Surgery, Saint Louis University Medical School, St. Louis, MO.
Address correspondence to Rose Christopherson, MD, PhD, Anesthesiology Service (P3ANES), VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, OR 97229. Address e-mail to rose.christopherson{at}med.va.gov.
BACKGROUND: A previously published clinical trial of epidural-supplemented versus general anesthesia, Veterans Affairs Cooperative Study No. 345, showed no difference in 30-day mortality and morbidity rates between the two treatments. We hypothesized that long-term postoperative survival would be increased by epidural anesthesia/analgesia supplementation during colon cancer resection.
METHODS: We studied long-term survival after resection of colon cancer in a trial of general anesthesia with and without epidural anesthesia and analgesia supplementation for resection of colon cancer in Veterans Affairs Cooperative Study No. 345. Cox and log-normal survival models were used to test the effects of pathological stage, type of anesthesia and other covariates on survival in 177 patients.
RESULTS: The presence of distant metastases had the greatest effect on survival. Thus, analyses were performed separately for patients with and without metastases. For those without metastasis, the hazard ratio for the treatment effects changed at 1.46 years. Before 1.46 years, epidural supplementation was associated with improved survival (P = 0.012), while later, the type of anesthesia did not appear to affect survival (P = 0.27). Hypertension was associated with poorer survival (P = 0.029), as was alcoholism in patients who received epidural anesthesia (P = 0.014). Survival of patients with metastases was unaffected by type of anesthesia. There was a significant age by hypertension interaction (P = 0.002). Patients survived longer if they were hypertensive, but had reduced survival if they were older than 66 years and hypertensive.
CONCLUSION: Epidural supplementation was associated with enhanced survival among patients without metastases before 1.46 years. Epidural anesthesia had no effect on survival of patients with metastases. Additional studies to confirm or refute these findings are warranted.
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