Overview

Over a comparatively short period, partial hepatectomy has been transformed from a high-risk, resource-intensive procedure to one that is now performed routinely, often removing a large amount of liver tissue and/or combined with resection of other organs, with the expectation of an uncomplicated postoperative course and recovery in most patients. Although reports of hepatic resection date back to antiquity (see the Introduction to this text), it was Lortat-Jacob’s report of an elective right hepatectomy for malignancy in 1952 that ushered in the modern era of hepatobiliary surgery, suddenly creating new possibilities to treat a wide range of disorders (Lortat-Jacob & Robert, 1952); however, from that point forward, the initial experience with hepatic resection was far from promising. In 1977, James Foster and Berman published a multiinstitutional summary of hepatic resection surgery in the United States composed of 168 resections performed over the preceding 14 years. This report documented a marked and unacceptably high operative mortality rate, which was due primarily to two often related factors: inability to control hemorrhage in the operating room and postoperative liver failure (Foster & Berman, 1977).

Since that time, progressive advances in many different areas have led to the improvement in outcome required for hepatic resection to take its place as a mainstream procedure. These advances have come on several fronts, and it is therefore difficult to single out one for special mention. Perhaps the most noteworthy gain has been a greater appreciation of the segmental anatomy of the liver and the willingness and ability of surgeons to pursue resections based on anatomic principles (see Chapters 1B, 90B, and 92). This particular element has had a profound effect, not only improving the results of major resections but spurring greater use of parenchyma-sparing sublobar resections, such as posterior or anterior sectoral hepatectomy or central hepatectomy, rather than right or extended right hepatectomy, respectively. Equally important, this change fundamentally altered the approach to patients who require bilobar resections.

A number of studies have documented this trend over time, and it has been associated with, and is probably responsible for, decreases in blood loss and transfusion rates, reductions in hospital stays, and decreases in operative mortality (Fan et al, 1999; Jarnagin et al, 2002; Belghiti et al, 2000).

Practice changes in other areas, including intraoperative and perioperative management and patient selection, have clearly contributed to the overall improvement in outcomes (see Chapter 22). The use of low central venous pressure (CVP) anesthesia, now widely used, represented a notable change in the previous standard practice of fluid loading prior to resection. Despite concerns of possible risks of air embolization or disturbance of renal function, both unfounded, low-CVP anesthetic management has been shown to reduce blood loss during the resection because of decreased filling pressures and reduced distension of the hepatic veins, and it does so with no significant untoward effects (Cunningham et al, 1994; Melendez et al, 1998).

Beyond the technical aspects of partial hepatectomy, a greater understanding of the impact of resection on the natural history of many diseases, combined with a clearer delineation of perioperative risk, have allowed a much more informed patient-selection process, one that has increasingly targeted resection more effectively to those patients most likely to benefit (see Chapter 49, Chapter 50A, Chapter 50B, Chapter 50C, Chapter 50D, Chapter 79A, Chapter 79B, Chapter 80, Chapter 81A, Chapter 81B, Chapter 81C ). Additionally, the quality and quantity of the future liver remnant has assumed great importance in patient selection for operations (see Chapter 93A, Chapter 93B ). Both of these issues have represented particularly critical developments for patients with hepatic colorectal metastases, for whom the advent of more active chemotherapeutic agents has led to more frequent treatment prior to operation. The latter development has greatly altered the landscape of this disease by allowing many more patients, particularly those with very advanced lesions previously considered surgically unapproachable, to undergo potentially curative surgery (Adam et al, 2000; Masi et al, 2009); however, while enhancing the results of resection, such therapy has the potential to cause significant hepatotoxicity and increase the risk of postoperative liver failure (see Chapters 65 and 87; Vauthey et al, 2006). In an effort to mitigate the risks in heavily pretreated patients and those with fibrosis or cirrhosis, preoperative portal vein embolization, first introduced 30 years ago, has been used with increasing frequency and has emerged as a powerful tool for inducing hypertrophy of the future liver remnant (see Chapter 93A, Chapter 93B ; Makuuchi et al, 1984).

This changing treatment paradigm in patients with hepatic colorectal metastases, with chemotherapy playing an increasingly prominent role, has yet to evolve in other malignant diseases; however, as more effective drugs emerge, it is more than likely that similar changes in practice will be seen in other tumor types. An example of note is biliary tract cancer: recent publication of the results of the ABC-02 trial holds some promise for better results with chemotherapy treatment (Valle et al, 2010).

Advances in imaging technology deserve special mention, as patient selection is continually refined. Whereas radiologic evaluation once required invasive investigations in many cases, it can now provide complete, noninvasive assessment of the liver, including the biliary tree, the arterial and venous anatomy, and the intrahepatic and extrahepatic disease extent in the case of malignant disease (see Chapters 13, 16, and 17). Indeed, for certain tumors, classic imaging findings are now considered pathognomonic and have supplanted the need for a biopsy. Specific examples in this regard include liver hemangiomata and focal nodular hyperplasia (see Chapter 17) and the guidelines for the diagnosis of hepatocellular carcinoma (Bruix & Sherman, 2005). Going forward, advances in imaging technology likely to influence the practice of hepatic resectional surgery include computer-aided reconstruction, functional imaging, and intraoperative navigation (Cherqui & Belghiti, 2009; Chopra et al, 2010).

Technical progress in other areas, particularly with devices such as vascular staplers and those used to transect the liver parenchyma (see Chapter 90B), is often hailed as a significant advance; however, although their value should not be dismissed, they cannot overcome poorly conceived or poorly executed operations, and their relative contribution, compared to the enhancements in other aspects, is modest at best.

Advances in imaging have also played a major role in postoperative management, particularly in diagnosing and treating postoperative complications. Over the past several years, the marked reduction in operative mortality after hepatic resection has seemingly occurred with little obvious change in morbidity (see Chapter 25). This observation suggests an overall improvement in the ability to salvage patients who experience significant complications. The ready availability of high-quality imaging and a heightened sense of awareness of the perioperative problems that may occur have led to earlier detection of complications. These changes, combined with the ability to manage many problems percutaneously or endoscopically, rather than operatively, have clearly had a major impact on perioperative outcome.

Conclusion

This chapter has detailed the contemporary approach to hepatic resection for a wide variety of diseases and indications (see Chapters 90B, 90C, and 90F), including the technical aspects of partial hepatectomy for living-donor transplantation (see Chapter 90D), and advances in minimally invasive approaches (see Chapter 90E) in particular, which represents a remarkable evolution in hepatic surgery; continued technical progress will certainly bring laparoscopic and robotic approaches to resection further into the mainstream. The descriptions herein reflect the current state of the art, built upon the collective contributions of many pioneering surgeons over the past several decades and continuing to the present. The techniques and approaches discussed include, to some degree, the biases of the authors; however, the overriding theme is always adherence to best principles of hepatic resection surgery, and alternative viewpoints must be considered where appropriate.