Angiogenesis is essential for breast cancer metastases formation and is mediated by vascular endothelial growth factor (VEGF) and prostaglandin E2 (PGE2). We hypothesized that serum levels of VEGF and PGE2 are increased by the stress response to breast cancer surgery and attenuated by paravertebral anesthesia and analgesia (PVAA). Thirty women undergoing mastectomy were enrolled in this prospective, randomized study, to receive general anesthesia (GA) and postoperative opioid analgesia (morphine 0.1 mg/kg bolus and patient-controlled infusion) or GA and PVAA (72-h infusion). All patients received rectal diclofenac. Venous blood samples were taken preoperatively and at 4 and 24 h postoperatively for serum glucose, cortisol, C-reactive protein, VEGF, and PGE2. PVAA inhibited the surgical stress response, as indicated by significantly less plasma glucose, cortisol, and C-reactive protein. VEGF and PGE2 values did not differ significantly between the groups. Mean (SD) percentage change in VEGF at 4 and 24 h respectively were 3% +/- 44% versus 9% +/- 80%, P=0.29 and 5% +/- 43% versus -10% +/- 63%, P=0.41 for patients with combined general and PVAA and GA alone, respectively. Mean percentage change in postoperative PGE2 at 4 and 24 h respectively was 10% +/- 17% versus 11% +/- 69%, P=0.29 and 34% +/- 19% versus 47% +/- 18%, P=0.15. We conclude that despite inhibiting the surgical stress response, PVAA had no effect on serum levels of putative breast cancer angiogenic factors, VEGF and PGE2.

M ethods of monitoring level of consciousness during anesthesia have been assessed for their validity, but no comparative study has focused on the practical usefulness of the Bispectral Index (BIS), processed electroencephalogram (pEEG), and Alaris auditory evoked potentials (A-AEP). Variables examined in this report are the success rate, the inappropriateness rate, responsiveness, and recovery time of the monitors.Ninety female patients scheduled for partial mastectomy agreed to participate in the study and were randomly divided into 3 groups. Anesthesia was induced with propofol and fentanyl to insert a laryngeal mask airway (LMA) and was maintained with the addition of nitrous oxide. The EEG was monitored continuously using the BIS, 90% spectral edge frequency (pEEG), or the A-AEP index. Success rate was the number of patients with low-enough impedance to extract good EEG signals at first placement of the electrodes. The number of patients with an index outside of the range (as shown by the manufacturer) considered appropriate under general anesthesia yielded an inappropriateness rate. Changes of the index by LMA insertion or surgical incision indicated responsiveness, and recovery time was the time to return to good EEG signals after signal disturbance by electric cautery.The success rate was 27 with BIS, 24 with A-AEP, and 15 with pEEG. Each index decreased in all 3 groups with induction of anesthesia. The inappropriateness rate was smallest with A-AEP, followed by BIS and pEEG (4, 9, and 14, respectively). Insertion of the LMA and skin incision markedly increased the index in the A-AEP group alone. Mean recovery times were 43 seconds in the BIS group, 19 seconds in the A-AEP group, and 11 seconds in the pEEG group. In all groups, arterial blood pressure and heart rate increased during anesthesia, were unchanged by LMA insertion or surgical incision, and returned to control values with LMA removal.This comparison of the clinical usefulness of EEG monitors found the BIS to have the largest success rate, the A-AEP the smallest inappropriateness rate and the largest responsiveness, and the pEEG the fastest recovery time with propofol-fentanyl-nitrous oxide anesthesia.

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