**3. Surgical procedures characterized by continuous single interruption of the porta hepatis for right trisectionectomy**

Foster said (1989), "Surgical technique is an art form. It can be very personal, based mostly on experience, or it can take a cookbook approach. For many standard operations, we follow in the ruts created by our teachers, perhaps adding a nuance or two called forth by an unusual situation or by a creative mind. Unfortunately, many years ago when I needed help, there was no available to teach me to operate on the liver" [14].

Multiple intermittent hepatic inflow occlusion for hepatic resection had been proposed. The significance of intermittent hepatic inflow occlusion for hepatectomy had been generally accepted [15]. Belghiti et al. [16] demonstrated that the intermittent interruption of flow through the porta hepatis with periods of 15 min of clamping and 5 min of unclamping led to better parenchymal tolerance than continuous flow interruption, especially in patients with abnormal liver parenchyma. The total ischemic time under intermittent interruption of flow through the porta hepatis for hepatectomy was approximately 30–90 min (2–6 times of clamping for 15 min each time). Nevertheless, in 1988, Rui reported his work on hepatectomy for primary liver cancer in Queen Mary Hospital (Hong Kong) titled *100 Cases of Hepatectomy under Normothermic Continuously Single Interruption of Porta Hepatis without Mortality*. We performed successfully major hepatectomy (Figure 1) for totally about 600 patients with HCC combined mostly with cirrhosis under normothermic continuous single interruption of porta hepatis. These studies were summarized in 20 cases of hemihepatectomy [17]; 4 cases of right trisectionectomy [18];179 cases of major hepatectomy, including 54 patients in elderly group and 125 in the nonelderly group [19]; and 33 cases of right trisectionectomy [9]. In the179 cases of major hepatectomy, the surgical procedures were shown in Tables 1 and 2. The postopera‐ tive complication rate was 10.6% (19/179), and the operative mortality was 1.1% (2/179). We noted that elderly HCC patients tend to presentations of significantly lower HBsAg positivity, smaller tumor sizes, less portal vein tumor thrombi (PVTT) and satellite nodule formation, earlier TNM staging, better differentiated tumors, less progressive, less aggressive, and less intrahepatically recurrence than that in the nonelderly. We found that Child–Pugh grading, PVTT, and Edmondson–Steiner grading independently predict postsurgical prognosis of elderly patients with HCC. In 2015, Uwatoko et al. [20] reported two cases of patients over 90 years old who underwent major hepatectomy for HCC, representing the oldest patients in the world to have done so. Generally, hepatectomy can be well tolerated for the elderly HCC patients, and a beneficial outcome similar to that of the nonelderly individuals can be expected, despite they had poorer liver function.

be obvious; (5) the Child–Pugh classification of liver function must be grade "A" and the indocyanine green retention rate at 15 min (ICGR 15) should be lower than 15% before surgery; and (6) serum bilirubin is less than 34 mmol/L, serum albumin higher than 30 g/L, and serum

A total of 459 primary liver cancer patients were hepatomized in our group. Among them, 33 cases of right trisectionectomies were performed. The patients included 24 males (72.7%) and 9 females (27.3%) with ages ranging from 15 to 69 years. Of the 33 cases, 28 (84.8%) were hepatitis B surface antigen (HBsAg) positive and 5 (15.2%) were negative. There were 8/33 cases (24.2%) with slight cirrhosis and 25/33 cases (75.8%) without cirrhosis; 22/33 cases (66.7%) were grade A in Child–Pugh classification, and 11/33 cases (33.3%) were grade B when the patients were hospitalized, but became grade A before surgical procedures through positive hepatic protective therapy; 27/33 cases (81.8%) with elevated serum α-fetoprotein (the highest value of AFP was 20,000 ng/ml) and 6/33 cases (18.2%) with normal α-fetoprotein. Sizes of tumor ranged from 8 to 20 cm. The stage of tumors was all IVa (T4N0M0). Pathological examination showed that 27 cases (81.8%) were hepatocellular carcinoma, 2 cases (6.1%) were cholangiocarcinoma, and 4 cases (12.1%) were mixed hepatocellular cholangiocarcinoma. Tumor thrombi were found in 17 cases (51.5%) in the right branch of the portal vein. Macro‐ scopic satellite nodules were found in 15 cases (45.5%) and did not presented in left lateral section of the liver. All right trisectionectomies were performed under continuous single interruption of porta hepatis. The 1-, 3-, and 5-year survival rates after right trisectionectomy were 71.9%, 40.6%, and 34.4%, respectively [9]. The longest cancer-free survival of right trisectionectomy in our group is 26 years. This patient is still alive in Beijing. Recently, it is reported from The National Health and Family Planning Commission of The People's Republic of China that a mean of 5-year survival rate for HCC is 10.1% in China. It is obvious that right

trisectionectomy would benefit the patients with resectable huge HCC.

**the porta hepatis for right trisectionectomy**

no available to teach me to operate on the liver" [14].

**3. Surgical procedures characterized by continuous single interruption of**

Foster said (1989), "Surgical technique is an art form. It can be very personal, based mostly on experience, or it can take a cookbook approach. For many standard operations, we follow in the ruts created by our teachers, perhaps adding a nuance or two called forth by an unusual situation or by a creative mind. Unfortunately, many years ago when I needed help, there was

Multiple intermittent hepatic inflow occlusion for hepatic resection had been proposed. The significance of intermittent hepatic inflow occlusion for hepatectomy had been generally accepted [15]. Belghiti et al. [16] demonstrated that the intermittent interruption of flow through the porta hepatis with periods of 15 min of clamping and 5 min of unclamping led to better parenchymal tolerance than continuous flow interruption, especially in patients with abnormal liver parenchyma. The total ischemic time under intermittent interruption of flow through the porta hepatis for hepatectomy was approximately 30–90 min (2–6 times of

prothrombin time larger than 60% before surgery.

286 Recent Advances in Liver Diseases and Surgery


**Table 1.** Summary of surgical type in 179 major hepatectomy under normothermic continuous single interruption of porta hepatis

In all of the major hepatectomy performed in our cohorts, the ischemic time under continuous single interruption of porta hepatis lasts generally 15 to 20 min, occasionally 40 min. The mean


**Table 2.** Survival rate of 179 cases of major hepatectomy for HCC under single time interruption of the porta hepatis

ischemic time in our cohorts is 20.6 min, which is much less than that of multiple intermittent hepatic inflow occlusion of the porta hepatic for major hepatectomy. The mean bleeding amount is 400 ml (400–2000 ml). The mortality and morbidity rates were 1.2% and 24.7%, respectively, indicating that the procedure can be carried out safely. In the process of hepatic resection under normothermic continuous single interruption of porta hepatis, the operative blood losing is much less, and the operating time is much shorter than that under multiple intermittent hepatic inflow occlusion. Capussotti et al. [21] reported their results of a prospec‐ tive, randomized clinical trial from Italy that is similar to our experience. It is obvious that major hepatectomy under normothermic continuous single interruption of porta hepatis can be well performed if the surgeon has meticulous skill in liver surgery. Therefore, the inter‐ mittent interruption of the porta hepatis may not be generally necessary. It is now commonly agreed that compared with intermittent multiple hepatic inflow occlusions, continuous single interruption of porta hepatis can simplify procedures, shorten operating time, and reduce blood losing, especially during transaction of liver parenchyma. In addition, it is well known that reperfusion injury following ischemia is a clinically important process that contributes significantly to tissue damage [22,23]. Continuous single interruption of the porta hepatis during liver resection not only diminishes blood losing but also may attenuate reperfusion injury following ischemia as compared with multiple intermittent interruption of the porta hepatis.

Moreover, we have demonstrated via animal experiment on rats that intermittent or continu‐ ous clamping leads to similar extent of postischemic liver injury after a total 40 min clamping of porta hepatis [24]. The total 40 min interruption of porta hepatis, either intermittently or continuously, may cause reversible liver injury shown mainly by ALT and AST, and slightly by MDA and SOD in rats (Figure 3). Structural alteration was seen in liver tissue and hepato‐ cytes but could recover gradually after blood perfusion was restored. Notably, no significant difference is seen in biochemical and structural injury between multiple intermittent and continuous single interruption, i.e., continuous single interruption of porta hepatis within 40 min would not significantly enhance the reversible injury of either liver structure detected by light and electron microscopy or liver functions detected by ALT and AST compared with the injury resulted from multiple intermittent interruption. Moreover, the levels of MDA, which is a marker for injury of peroxidation, resulted from ischemia/reperfusion, and SOD, which represents the scavenging potential for oxygen free radical, have no significant difference between continuous single interruption and intermittent interruption of porta hepatis for the total 40 min ischemia(p>0.05). In addition, this experiment showed that GSH might be a protectant from liver injury that resulted from ischemia/reperfusion(p<0.05) [22].

**Figure 3.** Comparison of liver injury induced by continuous single interruption and intermittent interruption of the porta hepatis via experiment on rats. Rats were divided into four groups (*n* = 8): (1) treated by intermittent interruption twice for 20 min each time with an interval of 5 min, (2) treated by continuous single interruption for 40 min, (3) treat‐ ed by intermittent in administration of GSH (reduced glutathione), and (4) treated by continuous single interruption for 40 min in administration of GSH through portal vein. Malondialdehyde (MDA) and Cu/Zn superoxide dismutase (SOD) are used for the detection of injury induced by oxygen free radical in ischemia/reperfusion and protection level, respectively. Blue color curve: intermittent interruption; red color curve: continuous single interruption. Pre: preinter‐ ruption of porta hepatis; After: postinterruption of porta hepatis; Reper: reperfusion after interruption. 1 vs 2 & 3 vs 4 :p>0.05; 1 vs 3 &2 vs 4 : p<0.05.

### **4. Surgical anatomy study of the hepatic veins**

ischemic time in our cohorts is 20.6 min, which is much less than that of multiple intermittent hepatic inflow occlusion of the porta hepatic for major hepatectomy. The mean bleeding amount is 400 ml (400–2000 ml). The mortality and morbidity rates were 1.2% and 24.7%, respectively, indicating that the procedure can be carried out safely. In the process of hepatic resection under normothermic continuous single interruption of porta hepatis, the operative blood losing is much less, and the operating time is much shorter than that under multiple intermittent hepatic inflow occlusion. Capussotti et al. [21] reported their results of a prospec‐ tive, randomized clinical trial from Italy that is similar to our experience. It is obvious that major hepatectomy under normothermic continuous single interruption of porta hepatis can be well performed if the surgeon has meticulous skill in liver surgery. Therefore, the inter‐ mittent interruption of the porta hepatis may not be generally necessary. It is now commonly agreed that compared with intermittent multiple hepatic inflow occlusions, continuous single interruption of porta hepatis can simplify procedures, shorten operating time, and reduce blood losing, especially during transaction of liver parenchyma. In addition, it is well known that reperfusion injury following ischemia is a clinically important process that contributes significantly to tissue damage [22,23]. Continuous single interruption of the porta hepatis during liver resection not only diminishes blood losing but also may attenuate reperfusion injury following ischemia as compared with multiple intermittent interruption of the porta

**Table 2.** Survival rate of 179 cases of major hepatectomy for HCC under single time interruption of the porta hepatis

**Year Overall survival rate Cancer-free survival rate**

 82.0% 73.1% 56.7% 53.2% 51.1% 46.0% 46.2% 44.5% 40.2% 38.1%

Moreover, we have demonstrated via animal experiment on rats that intermittent or continu‐ ous clamping leads to similar extent of postischemic liver injury after a total 40 min clamping of porta hepatis [24]. The total 40 min interruption of porta hepatis, either intermittently or continuously, may cause reversible liver injury shown mainly by ALT and AST, and slightly by MDA and SOD in rats (Figure 3). Structural alteration was seen in liver tissue and hepato‐ cytes but could recover gradually after blood perfusion was restored. Notably, no significant difference is seen in biochemical and structural injury between multiple intermittent and continuous single interruption, i.e., continuous single interruption of porta hepatis within 40 min would not significantly enhance the reversible injury of either liver structure detected by light and electron microscopy or liver functions detected by ALT and AST compared with the injury resulted from multiple intermittent interruption. Moreover, the levels of MDA, which is a marker for injury of peroxidation, resulted from ischemia/reperfusion, and SOD, which represents the scavenging potential for oxygen free radical, have no significant difference

hepatis.

288 Recent Advances in Liver Diseases and Surgery

Major hepatectomy under single interruption of porta hepatis requires fast operation in resection of liver lesion. It is most important for the liver surgeon to proficiently know the liver surgical anatomy. Hepatic vein is importantly related to the liver surgery. If hepatic vein is not treated perfectly in liver surgery, air embolization and bleeding may easily occur. Dai and Rui et al. [25] studied the anatomy of hepatic vein by perfusing ABS acetone solutions with various colors and then etching the liver parenchyma with HCl to show the draining variations of hepatic veins (Figure 4). We found that in 106 cases of livers from human fresh corpse, the draining variations of hepatic veins were rather popular. The variations appear mostly at Sg III, VI, and VII, least at Sg I, II, and VIII (Table 3). We also found that 80% (85/106) of middle vein and left vein join together into IVC (Figures 5 and 6), and 54.7% (58/106) middle vein is draining areas of VI, V, and VIII segments [25]. This work provides anatomic basis, especially when nonregular resection is performing and also warns to the liver surgeons to pay attention to the variations of hepatic veins. For example, during the execution of right trisectionectomy, the surgeons must carefully differentiate the middle hepatic vein (MHV) and the left hepatic vein (LHV) as well as their branch. In this case, the veins being taped must be MHV, as shown in Figure 6 (3,4), and RHV, as shown in Figure 6 (5,6), but not the HLV in Figure 6 (1,2) in the variants. As branches 1, 3, and 5 are rather thin, if any branch (such as 3 and 5 in Figure 6) of MHV and RHV is neglected and not taped, removing the liver being resected not only is impossible but also would subsequently lead to bleeding. Meanwhile, if the LHV or its branch (1,2) is taped, necrosis of the remnant liver parenchyma would happen. Any mistake would result in severe outcome.

**Figure 4.** Surgical anatomy study of hepatic veins. (1) Left hepatic vein (LHV); (2) middle hepatic vein (MHV); (3) right hepatic vein (RHV); (4) right posterior and inferior vein; (5) left intersectional plane vein; (6) IVC.


**Figure 5.** Photograph shows right hepatic vein (R), left hepatic vein (L), and Middle vein (M).

not treated perfectly in liver surgery, air embolization and bleeding may easily occur. Dai and Rui et al. [25] studied the anatomy of hepatic vein by perfusing ABS acetone solutions with various colors and then etching the liver parenchyma with HCl to show the draining variations of hepatic veins (Figure 4). We found that in 106 cases of livers from human fresh corpse, the draining variations of hepatic veins were rather popular. The variations appear mostly at Sg III, VI, and VII, least at Sg I, II, and VIII (Table 3). We also found that 80% (85/106) of middle vein and left vein join together into IVC (Figures 5 and 6), and 54.7% (58/106) middle vein is draining areas of VI, V, and VIII segments [25]. This work provides anatomic basis, especially when nonregular resection is performing and also warns to the liver surgeons to pay attention to the variations of hepatic veins. For example, during the execution of right trisectionectomy, the surgeons must carefully differentiate the middle hepatic vein (MHV) and the left hepatic vein (LHV) as well as their branch. In this case, the veins being taped must be MHV, as shown in Figure 6 (3,4), and RHV, as shown in Figure 6 (5,6), but not the HLV in Figure 6 (1,2) in the variants. As branches 1, 3, and 5 are rather thin, if any branch (such as 3 and 5 in Figure 6) of MHV and RHV is neglected and not taped, removing the liver being resected not only is impossible but also would subsequently lead to bleeding. Meanwhile, if the LHV or its branch (1,2) is taped, necrosis of the remnant liver parenchyma would happen. Any mistake would

**Figure 4.** Surgical anatomy study of hepatic veins. (1) Left hepatic vein (LHV); (2) middle hepatic vein (MHV); (3) right

hepatic vein (RHV); (4) right posterior and inferior vein; (5) left intersectional plane vein; (6) IVC.

result in severe outcome.

290 Recent Advances in Liver Diseases and Surgery

These veins run in the midplane of the liver (middle hepatic vein), the right intersectional plane (right hepatic vein), and the left intersectional plane (left hepatic vein). UV is the umbilical vein, which normally drains part of Sg 4 into the left hepatic vein.


**Table 3.** Variant rate of hepatic vein draining in 106 cases livers

**Figure 6.** The taping veins for right trisectionectomy in one type of variant. This figure shows one type of variant, i.e., middle vein and left vein joined together into IVC, in which 1 and 2 are of LHV and 3 and 4 are of MHC. During the execution of right trisectionectomy on this variant, the taped veins must be RHV (5,6) and MHV (3,4), but not LHV (1,2).
