Is preparation of a sterile operative field before percutaneous endoscopic gastrostomy necessary? A cost-effectiveness analysis

Background: Despite the non-sterile nature of the alimentary tract, percutaneous endoscopic gastrostomy (PEG) procedures are often performed after creating a sterile surgical field to reduce infection risk. Our group has previously demonstrated no statistically significant difference in the rate of surgical site infection (SSI) following PEG performed with or without sterile operative fields. The purpose of this study is to evaluate the cost-effectiveness of working with or without sterile operative fields during PEG. Methods: A decision tree model of PEG with and without sterile operative fields was created to evaluate the cost-effectiveness of these two methods. The primary outcome was incremental cost-effectiveness ratio with a ceiling willingness to pay threshold assumed of $100,000 per quality-adjusted life year (QALY). Costs were from the perspective of the healthcare system with a time horizon for the model of 90 days. Sensitivity analyses were performed on all model parameters. Results: In the base case analysis, sterile operative field PEG was cost-effective resulting in 0.2225 QALYs at an expected cost of $2,099. PEG procedures without a sterile operative field yielded less QALYs (0.2224) at a higher cost ($2,199) and were dominated. These procedures became cost-effective when the expected cost was < $1618 (e.g., $140 less than sterile operative field PEG) or when the SSI rate was < 1.6% (e.g., 0.2% higher than sterile operative field PEG) while holding all other variables constant. Conclusion: PEG procedures performed without a sterile operative field can be cost-effective compared to procedures performed with a sterile operative field if the rates of SSI remain similar. Cost savings from foregoing a sterile operative field appear to be offset if the SSI rate increases > 0.2% above that of sterile operative field PEG procedures.