Etiology and Functional Outcomes following Hypoxic Ischemic Encephalopathy in Adults: A 10-Year Retrospective Cohort Study

Abstract

Objectives

To investigate the etiology and outcome of patients with HIE admitted to a complex specialist rehabilitation facility over a 10-year period, to assess if numbers had changed, and to assess the effectiveness of rehabilitation for these patients. Hypoxic ischemic encephalopathy (HIE) is a leading cause of long-term neurologic disability.

Design

An observational retrospective cohort study.

Setting

A National Rehabilitation Hospital.

Participants

All health care records with an ICD-9 code (348.1) or ICD-10 code (G93.1) for HIE from 2008 to 2017 totaling 104 participants.

Intervention

Not applicable

Main Outcome Measures

Modified Barthel Index (MBI), Disability Rating Scale (DRS), Sensory Modality Assessment and Rehabilitation Technique scale, and discharge destination. Data were obtained from the patient administrative system of the brain injury program and were abstracted using a specially designed data abstraction tool. For statistical analysis, SPSS version 26.0 was used. Comparisons across etiologic groups were calculated using analysis of variance.

Results

A total of 572 episodes were recorded under the code G93.1; 468 did not meet the inclusion criteria and 104 records were reviewed systematically using a standardized data extraction proforma. Sixty-nine (66%) were male and 35 (33%) were female. Cardiovascular causes of HIE were most common (35.6%), followed by overdose (22.1%). Most had moderate to severe disability on admission (MBI and DRS). Severe disability was associated with respiratory arrest, overdose, and neurologic causes, whereas independence was associated with cardiovascular causes. MBI and DRS improved in the majority with the greatest improvements seen with cardiovascular etiology. In this cohort study, 45.2% of patients were discharged home, 18.3% to a nursing home, and 18.3% to an acute hospital.

Conclusion

Improvement in functional outcomes after HIE was correlated to etiology. This may have implications in helping to predict patient outcomes post-HIE. Study limitations include incomplete recordings in charts and varying sample sizes within etiologic groupings.