Caval reconstruction techniques in orthotopic liver transplantation

Table 1 Randomized controlled trial comparing conventional technique with venovenous bypass and piggyback technique

Variable	Conventional	Piggyback	P-value
n	34	33
Age	46.5 (24-73)	48 (18-66)	0.831
Child-Pugh Score			0.931
A	5	5
B	21	19
C	8	9
Anesthesia time (min) median (range)	795 (540-1115)	690 (510-1140)	0.162
Operative time (min) median (range)	647 (420-925)	600 (370-960)	0.270
Graft cold ischemia time (min) median (range)	536 (261-900)	497 (330-930)	0.205
Duration of mechanical ventilation (min) median (range)	712 (200-8070)	650 (0-26555)	0.429
Length of hospital stay (d) median (range)	15.5 (6-72)	17.0 (10-45)	0.846
Operative mortality (30 d)	0	1.3%	1.000
Red blood cells (units) median (range)	5.5 (0-34)	5.0 (0-35)	0.940
Fresh frozen plasma (units) median (range)	22.5 (0-84)	19.0 (0-82)	0.890
Platelet concentrate (units) median (range)	9.5 (0-40)	0.0 (0-30)	0.209
Aferesis platelet concentrate (units) median (range)	0.0 (0-3)	1.0 (1-10)	0.486
Crystalloid solution	1.5 (0-7.5)	1.5 (0-10)	0.985

Adapted from Isern et al[10], 2004.

Table 2 The piggyback technique

Ref.	n	Anastomosis	VVB	TPCS	Complications reported	Conclusion
Fleitas et al[26] single center	44 OLTs 39 patients	LM	No	No	Hepatic artery thrombosis (1), suprahepatic stricture (1), retransplant (5 - hepatic artery thrombosis, suprahepatic stricture, primary nonfunction, rejection), relaparotomy for bleeding (2), splenic steal (1)	Piggyback operation could be done in most OLTs, not restricted to certain anatomic situations. Lateral IVC clamping and unclamping results in good hemodynamic stability. Vascular complications, blood requirements, retransplantation, overall survival similar to that reported with standard technique
Belghiti et al[8] single center	51	LM	No	Yes, 100%	Four postoperative deaths (sepsis and primary nonfunction - 2, nosocomial pneumonitis at 3 and 5 mo - 2), no pulmonary embolism, NO IVC stump thrombosis	Piggyback technique was always technically feasible irrespective of graft size, VVB not required
Levi et al[27] single center	Era I: 945 of 1080 (87.5%)	LMR when possible	177 (18.7%)	No	Outflow obstruction (6)	Increasingly used piggyback technique over time (P < 0.0002). Over time had shorter warm ischemia time (P = 0.0004), less frequent need for VVB (P = 0.001). Hepatic venous outflow obstruction rarely encountered
	Era II: 851 of 920 (92.5%)	LMR when possible	97 (11.4%)	No	Outflow obstruction (3)
Ducerf et al[5]	88 OLTs, 81 patients	LM vs LM+ 3-cm cavotomy	No	No	No outflow obstruction (0)	Preservation of the IVC with recipient caval anastomosis with MHV and LHV is reliable. Associated cavotomy is not necessary
Parrilla et al[13] multi-center	1112	440 LM 672 LMR	No	6 at one center	Abdominal bleeding (2), acute outflow obstruction (9), ascites (3), intraoperative complications (28 - 2 venous tears, 26 congestion), graft failure (11)	Complications inherent to the piggyback technique including intraoperative venous congestion and acute and chronic Budd Chiari syndrome were more common when patients underwent anastomosis with two suprahepatic veins vs three (P < 0.001)
Cescon et al[4]	431	LM, LMR, LM+ 1 cm cavotomy	No	No	Complications related to anastomosis (20, 4.6%)	Increase in complications related to caval anastomosis in patients with two-vein anastomosis (LM vs LM+ P < 0.0001, LM vs LMR P = 0.065, LM+ vs LMR P = 0.4). Orifice formed with two veins is not sufficient. Advocate balloon angiography for dilation of anastomotic narrowing in most cases
Robles et al[17]	171	87 LM 84 LMR	No	No	Hepatic venous outflow obstruction in 7 patients with LM (8%) and in 1 patient with LMR (1.2%)	Increase in hepatic venous outflow obstruction in patients with two-vein anastomosis (P < 0.05)

LM: Anastomosis with left hepatic vein and middle hepatic vein; LMR: Anastomosis with left, middle and right hepatic veins; VVB: Venovenous bypass; TPCS: Temporary portocaval shunt; OLT: Orthotopic liver transplant; MHV: Middle hepatic vein; LHV: Left hepatic vein; IVC: Inferior vena cava.

Table 3 Comparison of standard and piggyback technique with and without venovenous bypass

Ref.	Comparison	Results
Tzakis et al[3]	24 piggyback, selective VVB 24 standard, selective VVB	No difference in blood loss, retransplantation rate, portal vein or hepatic artery thrombosis or biliary tract complications
Busque et al[33]	98 piggyback 33 standard, 15% VVB	Attempted piggyback in 131 patients. Were able to complete in 98
Reddy et al[14]	40 standard, routine VVB 36 piggyback, selective VVB	Piggyback associated with shorter anhepatic phase, shorter total operating time, less red blood cell use, trend towards shorter hospital stay, reduced hospital charges
Gerber et al[6]	75 piggyback 127 standard	Piggyback here done with triangular vagotomy at level of right hepatic vein. Decreased operative time, use of blood products, caval complications in piggyback group
Hosein Shokouh-Amiri et al[34]	34 piggyback 56 standard, routine VVB	Piggyback with 60% reduction in anhepatic phase, decreased operative time, higher core body temperature, decrease in fluid, plasma, platelets, RBC volume, 30% shorter ICU stay, hospital stay. Significant reduction in hospital costs
Barshes et al[12]	122 piggyback 98 standard, 76% VVB	Trend towards shorter operating time and ischemia time in piggyback group. Similar amount of blood products transfused. No hepatic vein thrombosis or strictures, no IVC strictures or thrombosis, no hepatic vein obstruction, no anastomotic strictures, no hemorrhagic complications
Nishida et al[35]	918 piggyback, 19.7% VVB 149 standard, 79.2% VVB	Blood transfusion, warm ischemia time, use of VVB were less in piggyback group. Liver, renal function similar
Sakai et al[36]	104 standard, with VVB 148 piggyback, with VVB 174 piggyback, without VVB	Piggyback without VVB required less RBCs, FFP, cryoprecipitate, cell-saver return, less acute renal failure, better patient and graft survival. The piggyback with VVB group had shorter operative time, warm ischemia time, and less acute renal failure than the standard with VVB group
Vieira de Melo et al[37]	125 standard, without VVB 70 piggyback, without VVB	Piggyback group had reduced surgical time, warm ischemia time, red blood cell use, FFP use, mortality at 30 d. No difference in cold ischemia time, length of stay, use of vasoactive drugs in ICU, period of intubation, duration of hospital stay, renal or graft function, need for reoperation, incidence of sepsis, biliary complications, vascular complications, need for retransplantation, 1-yr mortality. Cumulative survival at 1 yr significantly better in PB patients
Cabezuelo et al[38]	84 standard 20 standard with VVB 80 piggyback	Standard technique in comparison to piggyback technique is an independent risk factor for post-operative renal failure. VVB does not ameliorate this effect

VVB: Venovenous bypass; IVC: Inferior vena cava; ICU: Intensive care unit; RBC: Red blood cell; FFP: Fresh frozen plasma; PB: Piggyback.

Table 4 Side-to-side cavocaval anastomosis

Ref.	Anastomosis	Conclusion
Durand et al[39]	STSCCA	Low rates of postoperative renal failure. Maintained postoperative creatinine clearance. Preserved renal perfusion pressure, mean arterial pressure, cardiac index throughout procedure
Hesse et al[40]	STSCCA vs STSCCA with VVB vs STSCCA with TPCS	Lowest blood loss in group with VVB (no P-value reported). Highest red blood cell and fresh-frozen plasma transfusion in group without VVB or TPCS (P = 0.002). Changes in pre- and post-operative creatinine most pronounced in group with TPCS (not significant, no P-value reported)
Mehrabi et al[20]	STSCCA	Technique feasible in all patients, no anatomic limitations. Minimizes need for VVB or TPCS. Some patients with hepatic venous outflow obstruction managed with stenting, early revision or retransplant. Can apply technique in retransplants
Pisaniello et al[19]	STSCCA	Safe technique. Can be performed in most patients. Recommend post-anastomotic doppler ultrasonography

STSCCA: Side-to-side cavocaval anastomosis; VVB: Venovenous bypass; TPCS: Temporary portocaval shunt.

Table 5 Comparing standard technique with venovenous bypass to side-to-side cavocaval anastomosis

Ref.	Anastomosis	Conclusion
Zieniewicz et al[42]	STSCCA vs conventional with VVB	Reduction in warm ischemia time (P < 0.001) and blood loss in the STSCCA group (P < 0.001)
Remiszewski et al[43]	STSCCA vs conventional with VVB	Reduced complication rate (36% vs 30%) and reduced cost (P-value not reported) in STSCCA group
Khan et al[44]	STSCCA vs conventional with VVB	Reduced FFP (P = 0.03) and platelets (P = 0.04) transfused, shorter ICU stay (P = 0.005), less patients requiring ventilation after POD1 (P = 0.03) and less total days on the ventilator (P = 0.04) in STSCCA group. Comparable operating time, warm ischemia time, length of stay (P-value not reported). Outflow obstruction in 1.2% of STSCCA patients. Report hematoma formation as complication associated with VVB
Schmitz et al[45]	STSCCA vs conventional with VVB	Shorter warm ischemia times, reduced red blood cell (P = 0.000) and platelet transfusion (P = 0.002) in STSCCA group. Increased risk of hepatic artery stenosis (P = 0.045) and biliary leaks (P = 0.042) in the STSCCA group

STSCCA: Side-to-side cavocaval anastomosis; VVB: Venovenous bypass; ICU: Intensive care unit; FFP: Fresh frozen plasma.

Table 6 End-to-side cavocaval anastomosis

Ref.	Anastomosis	Conclusion
Polak et al[22]	ETSCCA	Simple and safe procedure. Allows wide anastomosis and eliminates risk of venous outflow tract obstruction. Can be performed without routine TPCS. Minimal intraoperative blood products used. Can be used in first and second retransplantations
Wojcicki et al[23]	ETSCCA	Low risk of vascular outflow obstruction complications with ETSCCA. Partial portal and mesenteric vein thrombosis not a contraindication for OLT, can treat with eversion thrombectomy
Belghiti et al[47]	STSCCA, ETSCCA	Caval preservation possible in most patients. Patients tolerate transient cross-clamping of the IVC prior to reperfusion when necessary to create wide anastomosis

STSCCA: Side-to-side cavocaval anastomosis; TPCS: Temporary portocaval shunt; ETSCCA: End-to-side cavocavostomy; IVC: Inferior vena cava; OLT: Orthotopic liver transplant.

Table 7 Comparing standard, piggyback and side-to-side cavocaval anastomosis

Ref.	Anastomosis	Conclusion
Lerut et al[16]	Conventional with routine VVB, piggyback with selective VVB, STSCCA	Piggyback and STSCCA groups had reduced warm ischemia time (P < 0.001), reduced need for intraoperative blood products (P < 0.01), lower rates of reoperation for bleeding (P < 0.01). STSCCA had higher frequency of immediate extubation (P < 0.001). STSCCA preserves advantages of piggyback technique including reduced implantation time and need for blood products while also eliminating VVB and reducing ventilation time
Navarro et al[48]	Piggyback, STSCCA, ETSCCA	Reduced vascular complication in STSCCA compared to piggyback group with less cases of Budd Chiari syndrome and fewer releases of the cavocaval running suture (no P-value reported)
Hesse et al[15]	Conventional with selective VVB, piggyback with selective VVB, STSCCA	Use of packed red blood cells higher in piggyback group than standard group (P = 0.01). Use of packed red blood cells (P = 0.01), number of patients operated on for hemorrhage (0.002) and use of VVB (P = 0.02) lower in STSCCA than other two groups. Perioperative FFP, time in ICU, postoperative graft function and survival similar between the three groups (P = NS, values not reported)
Lai et al[49]	Conventional with VVB, piggyback, STSCCA	STSCCA group with lowest median cold (P = 0.001) and warm ischemia times (P < 0.0001), best immediate postoperative graft function (P < 0.0001), lowest transaminase peak (P = 0.007) and best bile output (P = 0.003). No complications reported
González et al[50]	Conventional with VVB, conventional without VVB, IVC preservation	Total operating time (P = 0.004), packed red blood cell (P = 0.009), fresh frozen plasma (P = 0.005) transfusion lower in the IVC preservation group. Postoperative kidney and renal function did not differ between groups. Incidence of complications similar between groups

STSCCA: Side-to-side cavocaval anastomosis; ETSCCA: End-to-side cavocavostomy; IVC: Inferior vena cava; VVB: Venovenous bypass; ICU: Intensive care unit; NS: Non-significant.

Table 8 Comparison of piggyback and conventional in patients with hepatocellular carcinoma

	Conventional	Piggyback	P-value
n	19, 14%	119, 86%
Age (yr) (mean, median, range)	52, 52, 41-66	57, 57, 21-73	0.09
MELD at transplant (mean, median, range)	21, 22, 8-30	20, 22, 6-36	0.02
Total cold ischemia time (h) (mean, median, range)	8, 8, 4-13	7, 7, 3-17	0.03
Total warm ischemia time (min) (mean, median, range)	56, 59, 29-78	38, 29, 18-103	< 0.001
Outside milan criteria	15.80%	33.60%	0.18
Tumor number (mean, median, range)	2, 1, 1-4+	2, 1, 1-4+	0.6
Maximum tumor size (mean, median, range)	2.6, 2.7, 0.4-8.0	3.2, 3.0, 0.4-8.2	0.09
Tumor location bilateral	15.80%	24.40%	0.41
Lymphovascular invasion	21.10%	14.30%	0.49
Chemoembolization	10.50%	37.80%	0.02
1-yr overall survival	89.50%	83.20%	0.49
2-yr overall survival	84.20%	75.90%	0.55
Any HCC recurrence	5.30%	14.30%	0.47

Adapted from Mangus et al[51]. HCC: Hepatocellular carcinoma; MELD: Model for end stage liver disease.