Effects of liberal vs. conventional volume regimen on pulmonary function in posterior scoliosis surgery.

BACKGROUND We observed an increased rate of pulmonary complications (hypoxemia, pulmonary edema, re-intubation) in some patients after posterior spinal fusion, though standardized intraoperative volume regimens for major surgery were used. Therefore, we focused on the effects of two different standardized fluid regimens (liberal vs. conventional) as well as on two different types of postoperative pain management (thoracic epidural catheter vs. intravenous analgesia) concerning pulmonary function in patients undergoing posterior spinal fusion. METHODS 23 patients received a conventional intraoperative fluid management (crystalloids 5.5 ml/kg/h), whereas 22 patients obtained a liberal regimen (crystalloids approximately 11 ml/kg/h) during surgery. After surgery a thoracic epidural catheter was used in 29 patients, whereas 16 patients got a conventional intravenous analgesia. Regarding pulmonary outcome, the re-intubation rate, the postoperative oxygen saturations as well as delivery volumes and retention times of pleural drainages were evaluated. RESULTS Patients with conventional intraoperative fluid management had a less frequent reintubation rate (p = 0.015), better postoperative oxygen saturations (p = 0.043) and lower delivery volumes of pleural drainages (p = 0.027) compared to those patients with liberal volume regimen. Patients with thoracic epidural catheter had improved oxygen saturations on pulse oximetry at the first day after surgery (p < 0.001) and lower delivery volumes of pleural drainages than patients with intravenous analgesia (p = 0.008). CONCLUSIONS The combination of a more restrictive fluid management (better pulmonary oxygen uptake and ventilation, less pulmonary edema) and a thoracic epidural catheter (sympatholysis, pain management) in posterior spinal fusion may be advantageous as both factors can improve pulmonary outcome.