Is Portal Venous Pressure or Porto-systemic Gradient Really A Harbinger of Poor Outcomes After Living Donor Liver Transplantation?

Abstract

Background: Portal hyperperfusion as a cause of small for size syndrome (SFSS) after living donor liver transplantation (LDLT) remains controversial. Portal venous pressure (PVP) is often measured indirectly and may be confounded by central venous pressure (CVP).

Methods: In 42 adult cirrhotics undergoing elective LDLT, PVP was measured by direct canulation of portal vein and porto systemic gradient (PSG) was obtained after subtracting CVP from PVP. None underwent portal inflow modulation. SFSS was looked in 27 patients after excluding 15 with technical complications.

Results: Clinical features of SFSS found in 6 patients, 5 with graft recipient weight ratio (GRWR) > 0.8% and PVP < 20 mm of Hg. One with GRWR < 0.8% could truly be labeled as SFSS. Incidence of SFSS was not higher in patients with elevated PVP > 20 mm of Hg (14.3% vs 0%, P = 0.259) or PSG > 13 mm of Hg (33.3% vs 0%, P = 0.111). Intensive care unit (ICU) stay was longer in patients with elevated PVP (14.55 vs 9.13 days, P = 0.007) and PSG (16.8 vs 9.72 days, P = 0.009). There was no difference in graft functions, post-operative complications and mortality in first month post-LDLT.

Conclusion: Elevated PVP or PSG increased morbidity but neither predicted SFSS nor affected survival.

Keywords: BAL, bronchoalveolar lavage; CTP, Child Turcot Pugh; CVP, central venous pressure; GRWR, graft to recipient weight ratio; HAT, hepatic artery thrombosis; INR, International Normalized Ratio; LDLT, living donor liver transplant; MELD, Model for End Stage Liver Disease; MHV, middle hepatic vein; N, total number; P, probability value; PNF, primary non-function; PSG, porto systemic gradient; PVP, portal venous pressure; PVT, portal vein thrombosis; ROC, receiver operating characteristics; SD, standard deviation; SFSS, small for size syndrome; SGOT, serum glutamate oxaloacetate transaminase; SGPT, serum glutamate pyruvate transaminase; cirrhosis; graft recipient weight ratio; small for size syndrome.

Figure 1

ROC curve for PSG values.

Figure 2

Diagram showing the flow of participants through the study.