Impact on Renal Function and Hospital Outcomes of an Individualized Management of Cardiopulmonary Bypass in Congenital Heart Surgery: A Pilot Study

During cardiopulmonary bypass (CPB), high flows can allow an adequate perfusion to kidneys, but, on the other hand, they could cause emboli production, increased vascular pressure, and a more intense inflammatory response, which are in turn causes of renal damage. Along with demographic variables, other intra-operative management and post-operative events, this might lead to Acute kidney injury (AKI) in infants undergoing cardiac surgery. The aim of our study was to investigate if a CPB strategy with flow requirements based on monitoring of continuous metabolic and hemodynamic parameters could have an impact on outcomes, with a focus on renal damage. Thirty-four consecutive infants and young children undergoing surgery requiring CPB, comparable as for demographic and patho-physiological profile, were included. In Group A, 16 patients underwent, for a variable period of 20 min, CPB aiming for the minimal flow that could maintain values of MVO2 > 70% and frontal NIRS (both left and right) > 45%, and renal NIRS > 65%. In Group B, 18 patients underwent nominal flows CPB. Tapered CPB allowed for a mean reduction of flows of 34%. No difference in terms of blood-gas analysis, spectroscopy trend, laboratory analyses, and hospital outcome were recorded. In patients developing AKI (20%), renal damage was correlated with demographic characteristics and with renal NIRS during the first 6 h in the ICU. A safe individualized strategy for conduction of CPB, which allows significant flow reduction while maintaining normal hemodynamic and metabolic parameters, does not impact on renal function and hospital outcomes

Reply to Ji and Associates

neonatal cardiopulmonary perfusio

Cerebral perfusion strategy in a challenge cerebral vessels debranching

We present a case of antegrade cerebral perfusion based on a circuit with a centrifugal pump for general open-heart surgery to achieving cerebral protection during a challenging hybrid aortic arch repair

Improved Outcome of Cardiac Extracorporeal Membrane Oxygenation in Infants and Children Using Magnetic Levitation Centrifugal Pumps.

Extracorporeal membrane oxygenation (ECMO) has traditionally been and, for the most part, still is being performed using roller pumps. Use of first-generation centrifugal pumps has yielded controversial outcomes, perhaps due to mechanical properties of the same and the ensuing risk of hemolysis and renal morbidity. Latest-generation centrifugal pumps, using magnetic levitation (ML), exhibit mechanical properties which may have overcome limitations of first-generation devices. This retrospective study aimed to assess the safety and efficacy of veno-arterial (V-A) ECMO for cardiac indications in neonates, infants, and children, using standard (SP) and latest-generation ML centrifugal pumps. Between 2002 and 2014, 33 consecutive neonates, infants, and young children were supported using V-A ECMO for cardiac indications. There were 21 males and 12 females, with median age of 29 days (4 days-5 years) and a median body weight of 3.2\u2009kg (1.9-18\u2009kg). Indication for V-A ECMO were acute circulatory collapse in ICU or ward after cardiac repair in 16 (49%) patients, failure to wean after repair of complex congenital heart disease in 9 (27%), fulminant myocarditis in 4 (12%), preoperative sepsis in 2 (6%), and refractory tachy-arrhythmias in 2 (6%). Central cannulation was used in 27 (81%) patients and peripheral in 6. Seven (21%) patients were supported with SP and 26 (79%) with ML centrifugal pumps. Median duration of support was 82\u2009h (range 24-672\u2009h), with 26 (79%) patients weaned from support. Three patients required a second ECMO run but died on support. Seventeen (51%) patients required peritoneal dialysis for acute renal failure. Overall survival to discharge was 39% (13/33 patients). All patients with fulminant myocarditis and with refractory arrhythmias were weaned, and five (83%) survived, whereas no patient supported for sepsis survived. Risk factors for hospital mortality included lower (<2.5\u2009kg) body weight (P\u2009=\u20090.02) and rescue ECMO after cardiac repair (P\u2009=\u20090.03). During a median follow-up of 34 months (range 4-62 months), there were three (23%) late deaths and two late survivors with neurological sequelae. Weaning rate (5/7 vs. 21/26, P\u2009=\u2009NS) and prevalence of renal failure requiring dialysis (4/7 vs. 13/26, P\u2009=\u2009NS) were comparable between SP and ML ECMO groups. Patients supported with ML had a trend toward higher hospital survival (1/7 vs. 12/26, P\u2009=\u20090.07) and significantly higher late survival (0/7 vs. 10/26, P\u2009=\u20090.05). The present experience shows that V-A ECMO for cardiac indications using centrifugal pumps in infants and children yields outcomes absolutely comparable to international registry (ELSO) data using mostly roller pumps. Although changes in practice may have contributed to these results, use of ML centrifugal pumps appears to further improve end-organ recovery and hospital and late survival

Hemodynamic Analysis of Efficacy of Pulsatile Perfusion During Cpb With A New Centrifugal Pump

Objectives: New models of centrifugal pumps are claimed to have better hemodynamic performance in pulsatile perfusion during CPB. Few data are available for hemodynamic evaluation of these pumps in vivo, especially in highrisk groups as elderly patients. The study aims at comparing hemodynamic effects of pulsatile versus non-pulsatile perfusion using MEDOS DeltaStream- DP3 centrifugal pump in patients over 75 years old. Methods: Forty patients with severe aortic stenosis (mean age 80.7±3.3, mean EuroScore 5.8±1.4) undergoing AVR from 1.01.2010 to 31.01.2010 were prospectively randomized into pulsatile (n=20pts) and non-pulsatile groups (n=20pts). Pressure and flow curves were recorded simultaneously from external flow-meters (TransonicHT110) and pressure monitor at 6 time points during CPB (at pre-oxygenator, post-oxygenator, aortic cannula and patients radial artery levels). Pulsatility was quantified in terms of Energy Equivalent Pressure(EEP) and Surplus Hemodynamic Energy(SHE). Hemodynamic indexes and clinical effects were monitored during 24 hours peri-operatively. Results: Groups showed no difference in mean CPB time (p=0.98), cross-clamp time (p=0.95), mean perfusion flow (p=0.32) and pressure (p=0.16) values. In both groups the measured blood flow corresponded to the calculated one. Mean SHE generated at the outlet of the pump was 113.5±21.8 ergs/cm3 with further progressive drop along the circuit until 5.3+1.9 ergs/cm3 calculated in the patient (4.7% from initial level). The pulsatile group showed lower vascular resistance during CPB (p=0.035) and significant difference in SVR (p=0.04) and PVR (p=0.02) just after operation. Levels of SHE delivered to the patient correlated positively with urine output during CPB (R=0.34, p=0.041) and PVR after CPB (R=0.44, p=0.015). No differences between groups were found in pharmacologic support, transfusion rates, creatinine levels, respiratory indexes and intubation time. Longer ICU and hospital stay were related to severity of preoperative co-morbidities. Conclusions: Pulsatile flow produced by MEDOS DeltaStream-DP3 centrifugal pump results in hemodynamic advantages and better tissue perfusion in highrisk patients

Efficacy of Pulsatile Flow Perfusion in Adult Cardiac Surgery: Hemodynamic Energy and Vascular Reactivity

Background: The role of pulsatile (PP) versus non-pulsatile (NP) flow during a cardiopulmonary bypass (CPB) is still debated. This study's aim was to analyze hemodynamic effects, endothelial reactivity and erythrocytes response during a CPB with PP or NP. Methods: Fifty-two patients undergoing an aortic valve replacement were prospectively randomized for surgery with either PP or NP flow. Pulsatility was evaluated in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE). Systemic (SVRi) and pulmonary (PVRi) vascular resistances, endothelial markers levels and erythrocyte nitric-oxide synthase (eNOS) activity were collected at different perioperative time-points. Results: In the PP group, the resultant EEP was 7.3% higher than the mean arterial pressure (MAP), which corresponded to 5150 +/- 2291 ergs/cm(3) of SHE. In the NP group, the EEP and MAP were equal; no SHE was produced. The PP group showed lower SVRi during clamp-time (p = 0.06) and lower PVRi after protamine administration and during first postoperative hours (p = 0.02). Lower SVRi required a higher dosage of norepinephrine in the PP group (p = 0.02). Erythrocyte eNOS activity results were higher in the PP patients (p = 0.04). Renal function was better preserved in the PP group (p = 0.001), whereas other perioperative variables were comparable between the groups. Conclusions: A PP flow during a CPB results in significantly lower SVRi, PVRi and increased eNOS production. The clinical impact of increased perioperative vasopressor requirements in the PP group deserves further evaluation

Pulsatile cardiopulmonary bypass and renal function in elderly patients undergoing aortic valve surgery

OBJECTIVES: To evaluate if pulsatile cardiopulmonary bypass (CPB) has any protective influence on renal function in elderly patients undergoing aortic valve replacement (AVR). METHODS: Forty-six patients (>= 75 years old) with aortic valve stenosis underwent AVR with either pulsatile perfusion (PP) or non-pulsatile perfusion (NP) during CPB. Haemodynamic efficacy of the blood pump during either type of perfusion was described in terms of the energy equivalent pressure and the surplus haemodynamic energy. Urine samples were collected before surgery, at sternum closure, and at 2 and 18 h of intensive care unit stay to detect acute kidney injury markers. Perioperative urine levels of N-acetyl-beta-D-glucosaminidase (NAG), kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin (NGAL) were assessed together with plasma creatinine, creatinine clearance (CCr) and 24-h haemodynamic monitoring. Normally distributed continuous variables were described as mean +/- standard deviation and non-normally distributed data were presented as the median [25th-75th percentiles]. RESULTS: PP was characterized by a significantly higher amount of surplus haemodynamic energy transferred to the patients (P <0.001), with lower mean systemic vascular resistance during CPB (P = 0.020) and during 18 h postoperatively (group-P = 0.018). No difference was found between pre- and postoperative CCr in the PP group (71 +/- 23 vs 60 +/- 35 ml/min, P = 0.27), while its statistically significant perioperative decrement was observed in the NP group (67 +/- 24 vs 45 +/- 15 ml/min, P <0.001). The PP group showed significantly lower urinary levels of NAG at 18 h postoperatively (P = 0.008), and NGAL at sternum closure (P = 0.010), 2 h (P <0.001) and 18 h (P = 0.015) postoperatively. CONCLUSIONS: Short-term PP in elderly patients showed higher safety for renal physiology than NP, resulting in better maintenance of glomerular filtration and lower renal tissue injury