Risk of Hepatic Encephalopathy After TIPS
Patients undergoing TIPS should be counseled that hepatic encephalopathy occurs in approximately 25-50% of recipients, making it the most common and clinically significant complication of the procedure. 1
Incidence and Clinical Impact
The reported incidence of post-TIPS hepatic encephalopathy varies widely from 7-61% depending on how aggressively it is sought, with rates as high as 55% when systematic assessment is performed. 1, 2 This wide range reflects both patient selection factors and the intensity of post-procedural surveillance. 1
The impact on quality of life can be devastating—family members frequently report profound personality changes, with caregivers describing "I no longer recognize my husband/wife." 1 This is particularly heartbreaking when TIPS was performed as a palliative procedure for refractory ascites. 1
Patient-Specific Risk Factors
High-risk patients who should be carefully counseled or potentially excluded from elective TIPS include: 1
- Prior history of overt hepatic encephalopathy (strongest predictor—14% vs 2% risk of refractory HE) 3
- Advanced age (older patients have consistently higher risk) 1
- Advanced liver dysfunction (Child-Pugh Class C, particularly score ≥10) 1
- Hyponatremia 1
- Renal dysfunction 1
- Sarcopenia (reduced muscle mass) 1
- Diabetes mellitus (likely due to altered renal ammonia handling) 1
- Low serum albumin ≤2.5 g/dL (13.1% vs 3.1% risk of refractory HE) 3
Interestingly, lower baseline fasting ammonia concentrations (117 vs 227 μg/dL) paradoxically predict higher risk of post-TIPS HE, possibly reflecting impaired ammonia metabolism capacity. 4
Absolute and Relative Contraindications
Elective TIPS should be avoided in: 1
- Patients with cognitive impairment and limited family or social support 1
- History of debilitating encephalopathy, particularly in emergency variceal bleeding settings 1
- Severe or uncontrolled hepatic encephalopathy at baseline 1
Risk Mitigation Strategies
Pre-Procedural Assessment
For elective TIPS candidates, perform: 1
- Testing for covert/minimal hepatic encephalopathy using psychometric hepatic encephalopathy score (PHES)—a normal PHES provides 90% probability of remaining HE-free post-procedure 1
- Critical flicker frequency (CFF) testing—values >39 Hz have 100% negative predictive value for post-TIPS overt HE 1
- Quantitative EEG with spectral analysis (P3-4 lead <8 Hz is abnormal) 1
Procedural Modifications
To reduce HE risk: 1
- Use smaller diameter controlled-expansion stents (8mm vs >8mm) for elective TIPS in ascites—shunt size >8mm increases refractory HE risk from 3.4% to 18.5% 1, 3
- Consider embolization of spontaneous portosystemic shunts (SPSS) >6mm at the time of TIPS for ascites/hepatic hydrothorax 1
Prophylactic Medical Therapy
Prophylactic lactulose or rifaximin is NOT recommended for patients without prior overt HE history undergoing TIPS, as current evidence does not support routine prophylaxis. 1
Management of Post-TIPS Hepatic Encephalopathy
When overt HE develops after TIPS: 1
First-line medical management: Lactulose and rifaximin per standard HE treatment guidelines 1
For persistent or refractory HE despite maximal medical therapy: Consider TIPS stent diameter reduction or occlusion 1
Important caveat: While TIPS revision successfully improves refractory HE in 80% of cases (8 of 10 patients), 1-year survival without liver transplantation is only 10%, severely limiting the value of revision in non-transplant candidates. 3
Clinical Decision-Making Algorithm
For elective TIPS candidates:
- Assess all risk factors listed above 1
- If ≥2 major risk factors present (prior HE, Child-Pugh C, albumin ≤2.5), perform formal covert HE testing 1
- If covert HE detected or multiple risk factors: use 8mm stent and consider SPSS embolization 1, 3
- If prior overt HE + low albumin: strongly reconsider TIPS candidacy unless transplant-eligible 3
For emergency TIPS (variceal bleeding): History of debilitating encephalopathy remains a contraindication even in acute settings, as outcomes are poor with multi-organ dysfunction. 1