Hemodynamic variability in patients undergoing decompressive craniotomy or craniectomy: A scoping review

Area of Science:

• Neurosurgery
• Critical Care Medicine
• Autonomic Neuroscience

Background:

• Decompressive craniectomy (DC) treats intracranial hypertension in severe brain injury and stroke.
• Heart rate variability (HRV) and blood pressure variability (BPV) may indicate autonomic dysfunction and hemodynamic instability post-DC.
• The prognostic role of HRV and BPV in DC patients requires clarification.

Purpose of the Study:

• To map the existing evidence on heart rate variability (HRV), blood pressure variability (BPV), and related hemodynamic variability in patients undergoing decompressive craniectomy (DC).

Main Methods:

• A comprehensive scoping review was conducted following PRISMA-ScR guidelines.
• Searches were performed across major databases (MEDLINE, Embase, Cochrane CENTRAL, CINAHL, Web of Science) up to June 2025.
• Included studies of any design reporting temporal variability in heart rate or blood pressure in DC patients were screened and findings summarized descriptively.

Main Results:

• Twenty-three studies (1765 participants) were included, primarily focusing on severe traumatic brain injury.
• Reduced HRV post-DC was consistently associated with higher mortality and poorer neurological outcomes.
• Increased early postoperative systolic BPV independently predicted worse functional outcomes; certain anesthetic techniques reduced blood pressure fluctuations.

Conclusions:

• Limited evidence suggests reduced HRV and increased BPV predict worse outcomes in DC patients.
• HRV and BPV metrics show potential prognostic value.
• Future research should standardize measurements and prospectively validate whether targeting hemodynamic variability improves neurological outcomes.