Assessing Surgical Risk in Idiopathic Portal Hypertension: Some Answers, an Extrapolation, and More Questions
Authors: Douglas A. Simonetto, Patrick S. Kamath, Vijay H. Shah
Journal: Hepatology (2019)

Potential conflict of interest: Nothing to report. See Article on Page 911 Preoperative risk assessment of patients with chronic liver disease is an important part of hepatology practice. Patients with cirrhosis undergoing major surgery are at significantly increased risk of postoperative morbidity and mortality. It is the hepatologist’s responsibility to estimate such risk and advise the surgical team and the patient on how to proceed. Continued advances in surgical technologies and medical care are leading to increasing numbers of referrals for preoperative evaluation. Therefore, understanding the risks and benefits of such interventions in patients with chronic liver disease is paramount. Postoperative outcomes in patients with compensated and decompensated cirrhosis have been previously shown1 and recommended perioperative management of these patients has been recently summarized in an expert review.3 These studies, however, are limited to patients with cirrhosis, with or without clinically significant portal hypertension, and do not include patients with idiopathic noncirrhotic portal hypertension (IPH). One of the reasons for the paucity of studies on IPH is the uncommon nature of this condition, especially in the Western hemisphere, representing less than 10% of all cases of portal hypertension. Therefore, the postoperative outcomes in this population have not been explored. In the current issue of Hepatology, Elkrief et al.4 address this question by conducting a retrospective European multicenter study through the Vascular Liver Disease Interest Group. Forty‐four patients with biopsy‐proven IPH undergoing abdominal surgery were included. The first question that arises when assessing patients before surgery is how we can accurately predict outcomes, particularly their risk of dying postoperatively. Numerous scoring systems, generic and organ specific, have been proposed over the last several decades to help predict postsurgical morbidity and mortality risk. However, even the most comprehensive scoring systems cannot account for all disease‐specific elements. This has resulted in the widespread use of a broad and somewhat subjective classification system developed by Drs. Saklad, Rovenstine, and Taylor in 1941 and later endorsed by the American Society of Anesthesiologists (ASA).5 The ASA physical classification system was intended to help surgeons, anesthesiologists, and clinicians in assessing patients before invasive procedures. It defers to their clinical judgement on how to categorize patients’ risk according to their physical status. This system has been found to be predictive of perioperative mortality in patients with cirrhosis2; however, it has several limitations, including the lack of disease‐specific parameters. To counteract the limitations of the ASA physical status classification, prognostic scoring systems assessing the severity of liver dysfunction and portal hypertension have been investigated. The Child‐Turcotte‐Pugh (CTP) score7 and later the Model for End‐Stage Liver Disease (MELD)2 both showed a strong correlation with postoperative complications and mortality and are still used in the preoperative assessment of patients with cirrhosis. In 2007, our group proposed a modified preoperative scoring system combining the ASA classification, age, and the MELD score,1 which is available online (https://www.mayoclinic.org/medical-professionals/transplant-medicine/calculators/post-operative-mortality-risk-in-patients-with-cirrhosis/itt-20434721). The Mayo Postoperative Surgical Risk Score is able to predict postoperative mortality at 30 and 90 days and 1 year, independently of the type of surgery and with greater predictive value compared to MELD alone. It is important to emphasize, however, that the risk calculator was developed from retrospective data on patients who had been subjected to surgery. That is, they had been selected for surgery based on the surgeon’s best judgement. It is recognized that the surgeon’s “eye‐ball test” includes an assessment of frailty and nutrition that is not captured in any current risk scoring system. Although predictors of postsurgical outcomes in patients with cirrhosis have been validated and are now part of our routine preoperative risk assessment; the same is not the case for patients with IPH. The synthetic liver function is usually preserved in IPH, which hampers the utility of the MELD score in risk stratification of these patients. Instead, the presence and severity of portal hypertension–related complications are more likely to predict postoperative outcomes. Hepatic venous pressure gradient may also be used to determine portal hypertension severity in this population; however, its role on preoperative risk assessment in IPH still needs to be elucidated. As expected, hepatic function was mostly preserved in the current study by Elkrief et al., and the investigators did not find a correlation between serum bilirubin level and poor outcomes. Postoperative mortality in this population was associated only with serum creatinine level and age‐adjusted comorbidity index. However, the number of deaths was low and the number of patients with severe portal hypertension was small. Of 44 patients included, 18 had a history of variceal bleeding, 16 had a history of ascites, and none had hepatic encephalopathy. Although mortality was low, the rate of portal‐hypertension–related complications after surgery was high at 36% within 3 months and included refractory ascites (4%), hepatic encephalopathy (7%), variceal bleeding (4%), spontaneous bacterial peritonitis (7%), and acute kidney injury (16%). Furthermore, 50% of patients experienced an unfavorable outcome defined as either postoperative Dindo‐Clavien complication grade 3 or higher within 1 month after surgery, portal‐hypertension–related complications within 3 months, or death within 6 months after surgery. Poor outcomes were associated with history of ascites and possibly with serum creatinine and presence of IPH‐related extrahepatic conditions, although only a history of ascites reached statistical significance. This is not surprising given that ascites is often associated with renal dysfunction and increased risk for postoperative wound complications. Adequate ascites control before elective abdominal surgery and use of abdominal drains with continuous suction for days to weeks postoperatively along with parenteral albumin use can prevent the development of wound dehiscence. It is unclear from this retrospective study what measures were taken to control ascites in the perioperative period. The high rate of postoperative complications reported by Elkrief et al., particularly portal‐hypertension related, are striking considering the small number of patients with clinically significant IPH in the study. Given that there were only four deaths reported, it is difficult to make conclusions regarding factors predictive of mortality. It is possible that patients with more severe IPH, for example, those with diuretic‐intolerant ascites or overt hepatic encephalopathy, may experience higher mortality rates. Another question that remains is whether portal decompression impacts postoperative outcomes in this population. In patients with cirrhosis, the role of preoperative transjugular intrahepatic portosystemic shunt (TIPS) placement remains uncertain and is not currently recommended.3 Elkrief et al. tried to address this question and did not find a significant difference in postsurgical outcomes in those with a previous history of TIPS or surgical portosystemic shunt. However, the heterogeneous causes of portal hypertension in this group limit conclusions regarding the effect of portal decompression on complications. Nevertheless, the complication rate of portal venous decompression is significantly lower in patients with preserved synthetic liver function. Although anecdotally considered lower risk compared to cirrhosis, the findings from Elkrief et al. should make us pause when assessing patients with IPH before elective abdominal surgeries. Even though severity of portal hypertension, other than a history of ascites, was not found to negatively impact postoperative outcomes, the number of patients with severe IPH in the study was small. Furthermore, the study was limited to abdominal surgery, largely hernia repairs, and therefore caution is required in determining whether the results of the current article can be applied to all patients with IPH undergoing surgery. Given these limitations it is difficult to make recommendations regarding selection of patients for surgery, but, certainly, renal function and history of ascites should be factored into the decision making. Figure 1 provides an algorithm for surgical risk assessment of IPH compared to cirrhosis, but this extrapolation should be tempered by the limitations of the study as outlined. It requires prospective validation, which may not occur given the limited prevalence of IPH. More important, and independent of the surgical risk, medical management of portal hypertension and related complications should be optimized in the preoperative planning period.Figure 1: Algorithm is provided that compares preoperative risk assessment models of patients with cirrhosis and potential models in patients with IPH. *IPH‐associated extrahepatic conditions: immunological disorders, HIV infection, recurrent abdominal infection, medication or toxin, prothrombotic conditions, and genetic disorders. Abbreviations: Cr, creatinine; HIV, human immunodeficiency virus.