DRG 945 Overview

DRG 945 (Rehabilitation with Major Complication or Comorbidity/Complication or Comorbidity) captures inpatient stays where the primary focus is intensive rehabilitation for patients who also have significant medical complications or comorbidities. Typical cases include patients requiring multidisciplinary therapy after stroke, severe musculoskeletal injury, or neurologic events with concurrent medical instability. This Diagnosis-Related Group influences Medicare payment because case mix and documented complication or comorbidity levels affect reimbursement relative to standard rehabilitation DRGs. Accurate clinical documentation of the rehabilitation need and the presence of Major Complication or Comorbidity or Complication or Comorbidity is central to payment assignment.

Across commercial payers the reported rate range for DRG 945 spans roughly $2.6K up to $43K based on the payer-specific distributions shown in the table and chart below, with individual payer medians varying substantially. The widest spread is observed at Blue Cross Blue Shield, where values extend from the low thousands to as high as $43K, indicating substantial variability across claims. Refer to the table and chart below for payer-level quartiles and extremes.

• Rehabilitation intervention trials comparing multidisciplinary inpatient therapy intensities and modalities: randomized or pragmatic comparative studies test different combinations or doses of physical, occupational, and speech therapy for patients admitted primarily for inpatient rehabilitation with complicating comorbidities or complications (CC/MCC), such as post-stroke with cardiac disease or post-orthopedic surgery with infection. These studies focus on short-term functional gains, length of stay, and discharge disposition among medically complex rehab patients to determine optimal therapy plans. Results inform providers on tailoring intensity to clinical complexity and help payers evaluate value relative to cost and LOS for this high-resource DRG.
• Transitional care and readmission-reduction studies targeting post-discharge outcomes: cohort studies and randomized studies of discharge planning, early home-based therapy, tele-rehabilitation follow-up, or enhanced case management for patients leaving inpatient rehabilitation who have CC/MCC (for example, people with multisystem disease, cognitive impairment, or high fall risk). The objective is to reduce 30‑ and 90‑day readmissions, emergency visits, and functional decline by addressing medication reconciliation, caregiver training, and continuity of therapy. This research is relevant to hospitals and payers because reductions in readmissions and improved community function can lower downstream costs and improve reimbursement metrics tied to post-acute outcomes.
• Comparative effectiveness and prognostic research on patient selection and risk stratification for inpatient rehab versus alternative settings: observational studies and predictive-model development use administrative data and clinical measures to identify which medically complex patients (e.g., advanced cardiac or pulmonary disease, multiple pressure injuries, or concurrent infection) benefit most from inpatient rehabilitation rather than skilled nursing or home-based rehab. These studies examine functional trajectories, complications, and cost-effectiveness across care settings to guide appropriate site-of-care decisions. Findings help clinicians and utilization managers optimize placement, justify resource allocation for the DRG, and align payer authorization policies with expected outcomes.