Pulmonary Compliance Changes During Manipulation of Early Onset Scoliosis and Cast Application

Overview

No interventions outside the normal course of patient care. The investigators will be collecting data at specified points throughout the casting process. The proposed study will measure lung compliance during the casting process for spinal manipulation. Research questions include: Is there a quantifiable change in lung compliance during the casting process? Is there an individual change in lung compliance over time comparing collection points at each cast change? Is there a change in appearance of flow-volume loop? Is there a decrease in oxygen saturation from post-induction baseline? The investigators hypothesize that there is a change in lung compliance and a decrease in oxygen saturation during the casting process.

All patients undergoing spine manipulation and scoliosis casting will receive general anesthesia with a standard anesthetic technique regardless of if the patient is included in the study or not. The investigators will meet with the patient and the patient's parent/guardian prior to the procedure, which is traditionally done whether a patient participates in a study or not, to discuss the anesthetic plan. As part of the investigator's description of the anesthetic plan, the investigator will inform the patient and the parent/guardian of the study including the rationale for the study and the non-invasive means of obtaining data. The data will be obtained during the current cast application as well as any subsequent cast application surgeries that the patient will return for the future. A patient's cast will be changed approximately as needed per each child's circumstance; common time periods a child's cast may need to be changed include, but not limited to: growth, the cast becoming soiled, damaged, or other circumstances the study physician feels it is advisable to change the cast. The study will follow them until casting procedures are completed for treatment of scoliosis. The standard general anesthesia technique will be used. Please see Appendix A for suggested Anesthesia. There will be seven data collection points during the patient's general anesthetic: 1. Prior to the removal of the old cast, if applicable 2. After removal of old cast, if applicable 3. In frame, pre-traction 4. In frame, in traction 5. Post-body cast application (prior to cast windows; in traction) 6. Post cast application in bed out of traction (prior to cutting out windows) 7. Post-cast windows cut out (in bed, prior to return of spontaneous ventilation) The data collection will include the following physiologic parameters: 1. Non-invasive blood pressure 2. Heart rate 3. Oxygen saturation 4. The amount of traction (in pounds) that the patient is placed in for the spine manipulation. This will be measured at the beginning of traction, the beginning of cast application, and at the end of cast application. 5. Respiratory measurements from the Philips Spirometry Module, consisting of: 1. lung compliance 2. tidal volume 3. peak inspiratory pressure 4. flow volume loop 5. airway resistance Patients will also be subject to a chart review. The chart review will include previous anesthetic records which may provide valuable information concerning the patient's baseline lung compliance, tidal volume, peak inspiratory pressure, flow volume loop, and airway resistance, amount of traction applied and scoliosis curve correction. This previous data will be used to compare to the data collected before, during and after cast changes. Appendix A: Suggested Anesthesia 1. Premedication: 0.5mg/kg midazolam PO (max 15mg), PRN 2. Induction: Mask with sevoflurane in oxygen 3. Secure Intravenous Access 4. Intubation: Propofol 3-4mg/kg IV. Oral endotracheal tube. 5. Ventilation: Controlled using volume mode at 8ml/kg 6. Maintenance: oxygen, sevoflurane, controlled ventilation 7. Emergence: ondansetron 0.15mg/kg IV