Modifications of ALPPS - from complex to more complex or from complex to less complex operations.

BACKGROUND: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has recently been developed to induce rapid liver hypertrophy to reduce the chance of post-hepatectomy liver failure in patients with borderline or insufficient future liver remnant. ALPPS is still in an early developmental stage and its techniques have not been standardized. This study aimed to review the technical modifications of the conventional ALPPS procedure. DATA SOURCES: Studies were identified by searching MEDLINE and PubMed for articles published from January 2007 to December 2016 using the keywords "associating liver partition and portal vein ligation for staged hepatectomy" and "ALPPS". Additional articles were identified by a manual search of references from key articles. RESULTS: There have been a lot of modifications of the conventional ALPPS. These are classified as: (1) modifications aiming to improve surgical results; (2) modifications aiming to expand surgical indications; (3) salvage ALPPS; (4) ALPPS using the minimally invasive approach. Some of these modifications have made the conventional ALPPS procedure to become even more complex, although there have also been other attempts to make the procedure less complex. The results of most of these modifications have been reported in small case series or case reports. We need better well-designed studies to establish the true roles of these modifications. However, it is interesting to see how this conventional ALPPS procedure has evolved since its introduction. CONCLUSIONS: There is a trend for the use of minimally invasive procedure in the phase 1 or 2 of the conventional ALPPS procedure. Some of these modifications have expanded the use of ALPPS in patients who have been considered to have unresectable liver tumors. The long-term oncological outcomes of these modifications are still unknown.

Associating liver partition and portal vein ligation for staged hepatectomy: the current role and development.

BACKGROUND: Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has recently been developed to induce rapid liver hypertrophy and reduce post-hepatectomy liver failure in patients with insufficient future liver remnant (FLR). ALPPS is still considered to be in an early developmental phase because surgical indications and techniques have not been standardized. This article aimed to review the current role and future developments of ALPPS. DATA SOURCES: Studies were identified by searching MEDLINE and PubMed for articles from January 2007 to October 2016 using the keywords "associating liver partition and portal vein ligation for staged hepatectomy" and "ALPPS". Additional papers were identified by a manual search of references from key articles. RESULTS: ALPPS induces more hypertrophy of the FLR in less time than portal vein embolization or portal vein ligation. The benefits of ALPPS include rapid hypertrophy 47%-110% of the liver over a median of 6-16.4 days, and 95%-100% completion rate of the second stage of ALPPS. The main criticisms of ALPPS are centered on its high morbidity and mortality rates. Morbidity rates after ALPPS have been reported to be 15.3%-100%, with ≥ the Clavien-Dindo grade III morbidity of 13.6%-44%. Mortality rates have been reported to be 0%-29%. The important questions to ask even if oncologic long-term results are acceptable are: whether the gain in quality and quantity of life can be off balance by the substantial risks of morbidity and mortality, and whether stimulation of rapid liver hypertrophy also accelerates rapid tumor progression and spread. Up till now, the documentations of the ALPPS procedure come mainly from case series, and most of these series include heterogeneous groups of malignancies. The numbers are also too small to separately evaluate survival for different tumor etiologies. CONCLUSIONS: Currently, knowledge on ALPPS is limited, and prospective randomized studies are lacking. From the reported preliminary results, safety of the ALPPS procedure remains questionable. ALPPS should only be used in experienced, high-volume hepatobiliary centers.

Selective main portal vein clamping to minimize the risk of recurrence after curative liver resection for hepatocellular carcinoma.

BACKGROUND/AIMS: Our aim was to compare the postoperative outcomes of partial hepatectomy using Pringle maneuver and selective main portal vein clamping. METHODOLOGY: From January 2004 to December 2006, 169 consecutive patients received liver resection by the same surgical team. The surgical techniques were the same for all patients except for the hepatic vascular inflow occlusion techniques during liver parenchymal transection. Patients either received clamping of the portal triad (PTC group, n=118) or selective main portal vein clamping (PVC group, n=51). RESULTS: Operative time to carry out PVC was significantly longer than PTC (110.6±21.8 vs. 129.6±29.8min), however intraoperative blood loss was the same. There was no significant difference in operative mortality or morbidity rates, although the liver function recovered quicker in the PVC group. Significantly more patients in the PTC group developed HCC recurrence at postoperative one year than the PVC group (60.2% vs. 33.3%). There was no significant difference in overall survival between the 2 groups. Univariate analysis showed that clamping method, tumor size and BCLC grade were risk factors for disease-free survival (DFS) at one year, and multivariate analyses demonstrated clamping method and AFP level as independent risk factors for DFS. CONCLUSIONS: Patients subjected to selective portal vein clamping did better than those to Pringle maneuver in the postoperative outcomes. The underlying mechanism may be I/R injury of the liver remnant which might also contribute to an increase in tumor recurrence after liver resection.

Hemodynamics and oxygen transport dynamics during hepatic resection at different central venous pressures in a pig model.

BACKGROUND: Although low central venous pressure (CVP) has been used to minimize blood loss during hepatectomy, the impact of variations of CVP on the rate of blood loss and on the perfusion of end-organs has not been evaluated. This animal study aimed to evaluate the hemodynamics and oxygen transport changes during hepatic resection at different CVP levels. METHODS: Forty-eight anesthetized Bama miniature pigs were divided into 8 groups with CVP during hepatic resection controlled at 0 to <1, 1 to <2, 2 to <3, 3 to <4, 4 to <5, 5 to <6, 6 to <7, and 7 to <8 cmH2O. Intergroup comparisons were made for hemodynamic parameters, oxygen transport dynamics, and the rate of blood loss. RESULTS: The rate of blood loss and the hepatic venous pressure during hepatic resection were almost linearly related to the CVP. A significant drop in the mean arterial pressure, cardiac output, and cardiac index occurred between CVP ≥2 and <2 cmH2O. Oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction ratio (ERO2) remained relatively constant between CVPs of 2 to <8 cmH2O. There was a significant drop in DO2 when the CVP was <2 cmH2O. There was also a significant drop in VO2 and ExO2 when the CVP was <1 cmH2O. CONCLUSION: The optimal CVP for hepatic resection is 2 to 3 cmH2O.