In 1908, Pringle first described a technique to minimize blood loss during hepatic surgery by clamping the vascular pedicle.  The inflow of blood to the liver is via the hepatic artery and portal vein (see the image below). Surgeons must be able to isolate and control these sources of blood flow to control bleeding not only in traumatic injuries to the liver but also in elective hepatic resections.
Clamping of the hepatic pedicle, also known as the Pringle maneuver, allows surgeons to evaluate traumatic liver injury. It does so by allowing one to determine if the hemorrhage is from branches of the hepatic artery or the portal vein. When a clamp is applied to the pedicle, hemorrhage ceases if it is from either of these sources. If hemorrhage continues, the other likely sources of bleeding include the retrohepatic vena cava and hepatic veins. 
Traumatic injury to the liver can result in massive hemorrhage. Intraoperative blood loss is a major determinant of perioperative outcome.  Temporary control of hemorrhage is important in terms of buying time while the anesthesiologist restores the circulating volume before further blood loss occurs. It also allows time for repair of other injuries that may be of higher priority without unnecessary blood loss.  Once patients are stabilized, they may be taken back to the operating room for definitive procedures.
The Pringle maneuver is one technique that enables surgeons to halt hemorrhage and find the source of bleeding, allowing time for repair of the vessel. In the setting of hepatic resection of benign and malignant lesions, this maneuver can be used to assist with control of bleeding.  However, total vascular occlusion is more appropriate for hepatic resection. 
Ongoing bleeding may be controlled by this maneuver. If hemorrhage continues after this technique, hepatic bypass is an option. However, it may be more appropriate to perform damage-control laparotomy and tightly pack the liver.  This will allow for continued resuscitation and stabilization. The surgeon may return at a later time to reexplore and perform definitive repair.
Inferior vena cava (IVC) injuries can be lethal and difficult to isolate and repair. If the IVC is actively bleeding, exploration is warranted. When the right hemiliver is mobilized, an active rush of blood indicates an injury to the right or left hepatic vein. If there is a large retroperitoneal hematoma, then a retrohepatic vena cava injury is likely.
The liver should be packed and a sternotomy performed. The intrapericardial portion of the IVC can be controlled with a Rumel tourniquet (Heaney technique). This, along with the Pringle maneuver, allows time for the surgeon to repair the injured vessel. 
Selective inflow occlusion is not required for living donor hepatectomy. Total inflow occlusion using the Pringle maneuver can be performed without causing graft injury.  A study by Takatsuki et al found that whereas the Pringle maneuver could be safely performed in living donor hepatectomy, the only benefit was reduced blood loss during the donor surgery; they noted no significant positive impact on outcome for the recipient. 
A 2012 British trial comparing the efficacy of the Pringle maneuver combined with a low initial volume status (P+LCVP) to the Pringle maneuver with infrahepatic IVC clamping (P+IVCC) in complex liver resections demonstrated superiority of P+IVCC in decreasing blood loss, improving time to return of liver function, and decreasing the degree of renal dysfunction. 
No absolute contraindications to this procedure exist. For patients with impaired liver function, such as those with cirrhosis, clamping time until ischemia and portal hypertension is significantly reduced. In such instances, intermittent clamping for increments of 10 minutes at a time should be performed.