The effect of heparin on graft thrombosis in pediatric renal allografts

Abstract

Graft thrombosis is an important cause of early (<4 weeks) renal graft loss. Reports show that heparin reduces the incidence of early renal allograft thrombosis. Routine peri-operative administration of unfractionated heparin was introduced in our unit in 1994. We conducted a retrospective study of 254 transplants, undertaken in children, between 1987 and 2000. There were 126 children who did not receive heparin (group 1) and 128 who did (group 2). Recipient characteristics and immunosuppression were similar in both groups. The incidence of graft loss secondary to thrombosis was compared between the groups. Variables previously identified with increased risk of graft loss, including donor age, recipient age, cold ischaemia time (CIT), multiple donor vessels, surgical complications, and side of graft donation, were examined using logistic regression. Thrombosis occurred in 14 grafts in group 1 and 11 grafts in group 2 (odds ratio 0.7, 95% confidence interval 0.3-1.6, P=not significant). The mean time to graft loss was similar in groups 1 and 2 (6.6, SD 3.9, range 2-12 days and 7.9, SD 4.4, range 1-14 days, respectively) ( P=0.445). Young recipient age ( P=0.006), young donor age ( P=0.009), increasing CIT ( P=0.007), and surgical complications ( P=0.002) increased the risk of graft thrombosis. A reduction in the incidence of early renal allograft thrombosis upon introduction of heparin was not demonstrated.

Surgical complications in kidney transplantation in nonhuman primates

“…Comparing with adult patients, 14,15 the incidence in pediatric patients' is higher. 16 It is also a major postoperative complication in the nonhuman primate kidney transplantation model. 4,5 Our results reveal similar profile.…”

Pediatric transplantation: preventing thrombosis

“…Studies report conflicting data regarding the role of prophylactic antithrombotic therapy after kidney transplant [48,50,55,57,58]. Esfandiar et al [50] describe universal use of subcutaneous heparin 50 U kg À1 every 8 h postoperatively for 7 days, in addition to aspirin 5 mg kg À1 three times per week for 3 months.…”

“…Graft thrombosis is the second most common cause of graft loss (after rejection) with an overall incidence of around 2-3% (accounting for 10-15% of graft failure); however, there is wide variability (0-12%) between centers [47][48][49][50][51][52][53][54][55]. Risk factors for graft thrombosis include young recipient age (< 2 years), young donor age (< 5 years), donor-recipient vessel disparity, prolonged cold ischemic time, inherited and acquired thrombophilia, and preexisting thrombosis elsewhere [55,56].…”

“…Jurim (1995) [79] USA R/C LT/RLT 0-10 Not described HAT 29% (LT) vs. 0% (RLT) Kamel (2006) [80] Ireland R/C KT 0-18 None GT 5% Kanmaz (2014) [13] Turkey R/C LT 0-18 ASA HAT 3.9%, PVT 6.8% Karatzas (1997) [81] USA R/C LT All Not described HAT 11.4% Khan (2014) [82] Saudi Arabia R/C KT 0- [86] Italy R/C LT, < 6 kg 0-1 Not described HAT 0%, PVT 6% [12] Switzerland R/C LT 0-18 UFH, ASA, FFP HAT 1.8%, PVT 0.9% Millis (1996) [19] USA R/C LDLT/RLT 0-3 Not described ePVT 4-33%; dPVT 4-51% Miyagi (2014) [88] Japan R/C LDLT All Protease inhibitor Not reported Nagra (2004) [48] UK R/C KT 0-17 UFH vs. No prophylaxis GT 8% vs. 11% Neto (2007) [89] Brazil P/C LDLT < 10 kg 0-18 Not described HAT 3.1%, PVT 5.4% Neto (2012) [10] Brazil P/C LDLT 0-18 Not described HAT 4.3%, ePVT 2.6%, dPVT 5.8% Neto (2014) [90] Brazil P/C LDLT 0-18 UFH/VKA in high risk, dipyridamole PVT 7%…”

“…No graft thrombosis was observed in either group; however, one serious bleeding episode occurred in the high-intensity group. Nagra et al [48] were unable to show any benefit from routine weight-based low-dose subcutaneous heparin (1000-2500 units tds), but experienced increased bleeding in the treatment group. Some authors suggest selective heparinization only for higher risk groups (such as those with confirmed inherited thrombophilia), while others take the view that the efficacy of heparin in preventing vascular complications post-transplant is not established and the bleeding risk is too great to warrant routine thromboprophylaxis [48,55,56,59,60].…”