RACHS-1 (Risk Adjustment in Congenital Heart Surgery) Calculator

RACHS-1 (Risk Adjustment in Congenital Heart Surgery): Explanation and clinical context The RACHS-1 method groups pediatric congenital heart surgical procedures into six categories (1–6) of increasing expected operative risk to allow comparisons of in-hospital mortality between case mixes, institutions, or time periods. RACHS-1 was developed by consensus using the Pediatric Cardiac Care Consortium (PCCC) dataset and subsequent publications provide procedure mapping tables and validation in independent cohorts. RACHS-1 is intended as a procedure-based categorical risk adjuster: the primary output is a category (1 through 6).

It is not a patient-level continuous probability calculator by itself — observed mortality percentages for each category vary across cohorts, eras, and institutions; therefore use the category for benchmarking and case-mix adjustment rather than treating it as a single fixed predicted percent mortality. Clinical use notes: when multiple procedures are performed in the same operation, the RACHS-1 convention is to assign the highest applicable RACHS-1 category among the component procedures. The RACHS-1 classification excludes some specialty populations (e.g., adult transplant/ventricular assist device populations) and was intended for pediatric congenital cardiac surgical cohorts.

For exact mapping and exhaustive lists of procedure codes and their RACHS assignments consult the original RACHS-1 procedure table and subsequent validation papers; local adaptations (e.g., RACHS-ANZ, STAT/STS models) exist and are used in modern benchmarking when additional predictors are desired.