Propofol for pediatric radiotherapy

Safe anesthesia for radiotherapy in pediatric oncology: St. Jude Children's Research Hospital Experience, 2004-2006

PURPOSE

To determine the incidence of anesthesia-related complications in children undergoing radiotherapy and the associated risk factors.

METHODS AND MATERIALS

We retrospectively investigated the incidence and types of anesthesia-related complications and examined their association with age, weight, oncology diagnosis, type of anesthetic (propofol vs. propofol and adjuncts), total propofol dose, anesthetic duration, type of radiotherapy procedure (simulation vs. radiotherapy) and patient position (prone vs. supine).

RESULTS

Between July 2004 and June 2006, propofol was used in 3,833 procedures (3,611 radiotherapy sessions and 222 simulations) in 177 patients. Complications occurred during 49 anesthetic sessions (1.3%). On univariate analysis, four factors were significantly associated with the risk of complications: procedure duration (p <0.001), total propofol dose (p <0.001), use of adjunct agents (vs. propofol alone; p = 0.029), and simulation (vs. radiotherapy; p = 0.014). Patient position (prone vs. supine) was not significantly associated with the frequency of complications (odds ratio, 0.71; 95% confidence interval, 0.33-1.53; p = 0.38). On multivariate analysis, the procedure duration (p <0.0001) and total propofol dose (p < or =0.03) were the most significant risk factors after adjustment for age, weight, anesthetic type, and procedure type. We found no evidence of the development of tolerance to propofol.

CONCLUSION

The rate of anesthesia-related complications was low (1.3%) in our study. The significant risk factors were procedure duration, total propofol dose, the use of adjunct agents with propofol, and simulation (vs. radiotherapy).

Propofol sedation for longitudinal pediatric neuroimaging research

There is disagreement about allowing propofol sedation for research magnetic resonance imaging/spectroscopy (MRI/MRS) in children. Our study is the first to provide relevant safety and efficacy data. With institutional approval, 108 research MRI/MRS procedures under propofol sedation were performed longitudinally on children at ages 3-4 years (N=59) and 6-7 years (N=49). Sedation parameters, physiological values, and outcome data were collected. Success rate for acquisition of satisfactory quality MRI/MRS during propofol sedation was compared with that in typically developing, age-matched sleeping children. Only 5 minor events (2 with need to insert an oral airway, 2 with premature termination of study, 1 with bradycardia not requiring treatment) and no major events occurred. These safety/efficacy data are equal to or better than previously reported with propofol for clinically indicated procedures. A high percentage of parents of children participating in MRI/MRS studies at 3-4 years of age returned with their child at 6-7 years of age, and longitudinal follow-up was not adversely impacted by their child's experience with sedation. The success rate of data acquisition was significantly higher during propofol sedation (98%) than during late-night sleep studies in typically developing children (30%-50%). We conclude that propofol sedation for research MRI/MRS is safe and effective when children of appropriate ASA class are selected, supplemental oxygen is delivered, and sedation and monitoring are done by an experienced anesthesiologist.