Randomized trial comparing pulmonary alterations after conventional with venovenous bypass versus piggyback liver transplantation

Abstract

During the anhepatic phase of conventional liver transplantation (LT), the inferior vena cava (IVC) is crossclamped and venovenous bypass (VVB) is usually indicated for diversion of IVC and portal blood flow. VVB can theoretically lead to pulmonary complications due to the contact of the blood with the surfaces of the circuit. In the piggyback method, preservation of the IVC avoids VVB. The aim of this study is to compare pulmonary alterations after conventional with VVB versus piggyback LT. Sixtyseven patients were randomized for conventional VVB (n ‫؍‬ 34) or piggyback (n ‫؍‬ 33) LT. Pulmonary static compliance (C st ) and Pa O2 /F IO2 ratio were measured preand post-LT. Chest X-rays were obtained daily from the 1st to the 5th postoperative day. Pre-and post-LT C st were 73.4 ؎ 36.0 mL/cm H 2 O and 59.7 ؎ 22.0 mL/cm H 2 O in the conventional group and 69.1 ؎ 20.0 mL/cm H 2 O and 58.7 ؎ 27.1 mL/cmH 2 O in the piggyback group. The difference between the two groups was not significant (P ‫؍‬ .702). C st significantly decreased after LT (P ‫؍‬ .008). The pre-and post-LT Pa O2 /F IO2 were 455.6 ؎ 126.6 mm Hg and 463.1 ؎ 105.9 mm Hg in the conventional group and 468.9 ؎ 114.1 mm Hg and 483.3 ؎ 119.8 mm Hg in the piggyback group. The difference among the two groups was not significant (P ‫؍‬ 0.331). There was no significant difference after LT (P ‫؍‬ .382). Upon the radiological evaluation, piggyback group presented a higher frequency of pulmonary infiltrates (80.6% vs. 50.0%; P ‫؍‬ .025). In conclusion, piggyback LT recipients have a higher rate of pulmonary infiltrates when compared to those operated upon using the conventional VVB method. (Liver Transpl 2004;10:425-433.) C urrently, 2 main methods of liver transplantation (LT) are employed. 1 In the conventional method, the retrohepatic portion of the inferior vena cava (IVC) is cross-clamped and resected in block with the native liver. This maneuver can lead to pulmonary complications secondary to the temporary reduction of the venous blood return of the lower extremities and splanchnic bed. 2 Patients with poor hemodynamic tolerance to IVC and portal vein clamping will require fluid infusion during the anhepatic phase. 2 After graft reperfusion, the restoration of the venous return results in a sudden central volume overload that can cause pulmonary edema. 2 A concurrent mechanism is the release into the systemic circulation of proinflammatory substances produced in the graft itself during the ischemia-reperfusion injury, and in the obstructed venous beds during blood stagnation. 3 These substances may produce left ventricle dysfunction, increase pulmonary capillary pressure, and alter capillary permeability. 3 All these actions can contribute to pulmonary dysfunction.To overcome these disorders, venovenous bypass (VVB) is usually indicated, allowing the diversion of the IVC and portal blood flow to the superior vena cava. 2 Despite these advantages, VVB can also cause pulmonary complications. Although rare, some can be fatal, like air or thrombotic pulmonary em...

Intereukin-10 and Kupffer cells protect steatotic mice livers from ischemia-reperfusion injury

“…During the anhepatic phase of a liver transplant procedure; the portal vein is divided, followed by anastomosis of the native portion to the donor organ. Despite techniques for decompression of the splanchnic circulation, bowel congestion secondary to reduced portal outflow remains a feature of clinical transplantation [8]. Bacterial products, in particular lipopolysaccharide (LPS, endotoxin), a component of Gram-negative bacterial cell walls, are thought to translocate across the bowel wall during portal venous stasis.…”

Bacterial translocation during liver transplantation: A randomized trial comparing conventional with venovenous bypass vs. piggyback methods

“…A retrospective study comparing 24 patients submitted to conventional LT with venovenous bypass and 27 operated using the piggyback method was conducted in our service, detecting an incidence of pulmonary infiltrates significantly higher in the piggyback group 21. To confirm it, a prospective study was done including 67 patients, with similar results, but there were no statistically significant differences regarding pulmonary function outcomes, mechanical ventilation time, length of hospital stay, and operative mortality 26. In parallel with it, we have tried to identify some possible factors involved, investigating metabolic and inflammatory aspects (studies still underway).…”

The Routinely Use of “Piggyback” Technique in Adult Orthotopic Liver Transplantation

“…A decrease greater of 50% in median arterial pressure for more than one minute is described as "reperfusion syndrome" and has been reported in 30% of cases (Figueras, 2001) and two cases out of 1361 transplants presented with hemodynamic shock on reperfusion (Navarro, 1999). The PB technique has been found to be associated with more pulmonary infiltrates (Isern, 2004), but this was not clinically relevant or statistically significant when compared with the classic technique .…”