Modified ultrafiltration & postoperative course in patients undergoing
repair of Tetralogy of Fallot
Abstract
Background: Expected benefits of modified ultrafiltration(MUF) include
increased hematocrit, reduction of total body water & inflammatory
mediators, improved left ventricular systolic function, & improved
systolic blood pressure and cardiac index following cardiopulmonary
bypass(CPB). This prospective randomized trial tested this hypothesis.
Methods: 79 patients undergoing intracardiac repair of Tetralogy of
Fallot(TOF) were randomized to MUF group(Group-M, n=39) or only
conventional ultrafiltration(CUF) group(Group-C, n=40). Primary outcome
was change in hematocrit. Secondary outcomes were changes in peak airway
pressures, ventilatory support, blood transfusions, time to peripheral
rewarming, mean arterial pressure, central venous pressure, inotrope
score(IS) and cardiac index. Serum inflammatory markers were measured.
Results: Following MUF, Group-M had higher hematocrit(44.3±0.98 g/dl)
compared to Group-C(37.8±1.37g/dl),P=<0.001. Central venous
pressure(mmHg) immediately following sternal closure was 9.27±3.12mmHg
in Group-M & 10.52±2.2mmHg in Group-C(P=0.04). In the ICU, they were
11.52±2.20mmHg in Group-C and 10.84±2.78mmHg in Group-M(P=0.02). Time to
peripheral rewarming was 6.30±3.91 hours in Group-M and 13.67±3.91hours
in Group-C(P=0.06). Peak airway pressures in ICU were 17±2mmHg in
Group-M & 20.55±2.97mmHg in Group-C, P<0.001. Duration of
mechanical ventilation was 6.3±2.7 hours in Group-M compared to 14.7±3.5
hours in Group-C(P=0.002). IS was 11.52±2.20 in Group-C compared to
10.84±2.78 in Group-M. 8/39(20.5%) patients in Group-M had
IS>10 compared to 22/40(55%) patients in Group-C(P=0.02).
Serum Troponin-T and Interleukin-6 levels were lower in Group-M; TNF-α
and CPK-MB were similar. ICU & hospital stay were similar. Conclusion:
MUF group had higher post-operative hematocrit, decreased duration of
mechanical ventilation, lower need for inotropes & lower Interleukin-6
& Troponin-T levels. MUF group had better post-operative outcomes.