A risk stratifying tool to facilitate safe late-stage percutaneous endoscopic gastrostomy in ALS

Background: The safety of percutaneous endoscopic gastrostomy (PEG) insertion in amyotrophic lateral sclerosis (ALS) patients with significant respiratory compromise has been questioned. Objectives: To review the characteristics of an ALS clinic patient cohort undergoing PEG, and the introduction of a risk stratification tool with procedural adaptations for higher-risk individuals. Methods: Patients undergoing PEG insertion were analysed (n = 107). Cases stratified as higher-risk underwent insertion in a semi-recumbent position, minimising sedation, with the option of nasal non-invasive ventilation. Results: All underwent successful PEG. One-third had pre-procedure FVC ≤50% (mean, 64 ± 22%). Of those who underwent PEG insertion after introduction of risk stratification (n = 58), 39 (67%) met criteria for being higher risk, 16 (41%) of whom had FVC ≤50% (p = 0.005). High-risk patients received lower sedative doses vs. the low-risk group (midazolam 2.1 ± 1.1 vs.2.8 ± 0.95mg, p = 0.021; fentanyl 42 ± 16 vs. 60 ± 21μg, p = 0.015). Four deaths occurred within one month of insertion (attributable to the natural disease course). Conclusions: Risk stratification identified a greater number of patients with evidence of respiratory compromise than using the sole criterion of FVC ≤50%. A modified PEG procedure enabled safe insertion despite respiratory compromise, in those who might not have tolerated attempted insertion by alternative means such as radiologically-inserted gastrostomy.