Hemodynamic monitoring in thoracic surgical patients.

PURPOSE OF REVIEW: This article reviews the technology and clinical data describing hemodynamic monitoring devices available to anesthesiologists and intensivists caring for patients undergoing thoracic surgical procedures, so that they may better utilize available technology to improve outcomes in this high-risk surgical population. RECENT FINDINGS: Noninvasive stroke volume monitors are based on several different technology platforms, all of which have distinct performance characteristics. Strong clinical outcomes data support the use of these devices in patients undergoing major surgical procedures although these studies generally do not target thoracic surgical procedures specifically. The predictive ability of respiratory variation (for measuring fluid responsiveness) is controversial in both one lung and low tidal volume ventilation. Extravascular lung water measurements are well validated, predict postoperative lung function, but require the use of transpulmonary thermodilution. SUMMARY: Technology that has been shown to improve clinical outcomes in major surgical procedures is likely applicable to patients undergoing thoracic surgical procedures; however, several unique features of these procedures limit or modify the way in which these devices can be used. Understanding the scientific basis of these devices is the key to using them effectively.

A Clinical Comparison of Intravenous and Epidural Local Anesthetic for Major Abdominal Surgery.

BACKGROUND: Epidural analgesia provides good pain control after many postoperative procedures, but it can lead to complications, has some contraindications, and occasionally fails. Intravenous lidocaine infusion has been suggested as an alternative. We assessed, in our clinical practice, the effects of perioperative intravenous lidocaine infusion compared with epidural analgesia for major abdominal surgery. METHODS: We conducted a retrospective review of patients who had received intravenous lidocaine (1 mg/kg per hour) perioperatively after a major abdominal surgery. We matched them with patients who had received epidural analgesia. We tested a joint hypothesis of noninferiority of lidocaine infusion to epidural analgesia in postoperative pain scores and opioid consumption. We assigned a noninferiority margin of 1 point (on an 11-point numerical rating scale) difference in pain and a ratio [mean (lidocaine) / mean (epidural)] of 1.2 in opioid consumption, respectively. RESULTS: Two hundred sixteen patients (108 in each group) were analyzed. Intravenous lidocaine was not inferior to epidural analgesia with respect to pain scores. Lidocaine infusion was inferior to epidural analgesia with respect to opioid consumption. Patients in the lidocaine group had fewer episodes of hypotension and less postoperative nausea and vomiting, pruritus, and urinary retention. Patients receiving lidocaine also had earlier urinary catheter removal and earlier first gastrointestinal function. Daily mental status assessment was similar between the 2 groups. CONCLUSIONS: Patients who received systemic lidocaine infusions with the addition of PRN (as needed) opioids administered for breakthrough pain did not have clinically significant differences in pain scores on postoperative day 2 and beyond. Intravenous lidocaine infusion in major abdominal surgery was inferior to epidural analgesia with respect to opioid consumption. However, lidocaine was associated with improvements in several important aspects of recovery.

Evolutionary relationships of "Candidatus endobugula" bacterial symbionts and their Bugula bryozoan hosts.

Ribosomal gene sequences were obtained from bryozoans in the genus Bugula and their bacterial symbionts; analyses of host and symbiont phylogenetic trees did not support a history of strict cospeciation. Symbiont-derived compounds known to defend host larvae from predation were only detected in two out of four symbiotic Bugula species.