Unique static discharge events on two CentriMag® (2nd Gen) ECMO patients causing console failure.

The use of ECMO for cardiovascular support continues to increase in the United States and around the world. It is not a benign endeavor as serious complications may occur. We present our experience of two second generation CentriMag® (Abbott formerly Thoratec Inc.) console failures that occurred while transporting the patients to other areas of the hospital. In each incident, the patients were immediately placed on back-up units and the transport continued. No patient complications could be attributed to the failures. An investigation by Abbott engineers traced the failure to a static build-up and discharge caused by a non-manufacturer-approved metal rod that was utilized to mount the external monitor. The static discharge caused a disruption of electrical continuity between the control system and the motor, stopping the motor as well as the monitoring system. Removal of the mounting rod prevented replication of the situation in the lab. We have removed the rod from our clinical units and have not experienced any other pump failures.

Laboratory Evaluation of Hemolysis and Systemic Inflammatory Response in Neonatal Nonpulsatile and Pulsatile Extracorporeal Life Support Systems.

The objective of this study was to compare the systemic inflammatory response and hemolytic characteristics of a conventional roller pump (HL20-NP) and an alternative diagonal pump with nonpulsatile (DP3-NP) and pulsatile mode (DP3-P) in simulated neonatal extracorporeal life support (ECLS) systems. The experimental neonatal ECLS circuits consist of a conventional Jostra HL20 roller pump or an alternative Medos DP3 diagonal pump, and Medos Hilite 800 LT hollow-fiber oxygenator with diffusion membrane. Eighteen sterile circuits were primed with freshly donated whole blood and divided into three groups: conventional HL20 with nonpulsatile flow (HL20-NP), DP3 with nonpulsatile flow (DP3-NP), and DP3 with pulsatile flow (DP3-P). All trials were conducted for durations of 12 h at a flow rate of 500 mL/min at 36°C. Simultaneous blood flow and pressure waveforms were recorded. Blood samples were collected to measure plasma-free hemoglobin (PFH), human tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-8, in addition to the routine blood gas, lactate dehydrogenase, and lactic acid levels. HL20-NP group had the highest PFH levels (mean ± standard error of the mean) after a 12-h ECLS run, but the difference among groups did not reach statistical significance (HL20-NP group: 907.6 ± 253.1 mg/L, DP3-NP group: 343.7 ± 163.2 mg/L, and DP3-P group: 407.6 ± 156.6 mg/L, P = 0.06). Although there were similar trends but no statistical differences for the levels of proinflammatory cytokines among the three groups, the HL20-NP group had much greater levels than the other groups (P > 0.05). Pulsatile flow generated higher total hemodynamic energy and surplus hemodynamic energy levels at pre-oxygenator and pre-clamp sites (P < 0.01). Our study demonstrated that the alternative diagonal pump ECLS circuits appeared to have less systemic inflammatory response and hemolysis compared with the conventional roller pump ECLS circuit in simulated neonatal ECLS systems. Pulsatile flow delivered more hemodynamic energy to the pseudo-patient without increased odds of hemolysis compared with the conventional, nonpulsatile roller pump group.

Hemodynamic evaluation of the Avalon Elite bi-caval dual lumen cannulae.

In previous studies, we have evaluated the hemodynamic properties of selected oxygenators, pumps (centrifugal and roller), and single lumen cannulae. Because the dual lumen cannulae are widely used in veno-venous extracorporeal life support (ECLS) and are receiving popularity due to their advantages over the single lumen cannulae, we evaluated the flow ranges and pressure drops of three different sizes of Avalon Elite dual lumen cannulae (13Fr, 16Fr, and 19Fr) in a simulated neonatal ECLS circuit primed with human blood. The experimental ECLS circuit was composed of a RotaFlow centrifugal pump, a Capiox BabyRX05 oxygenator, 3 ft of 1/4-in venous and arterial line tubing, an Avalon Elite dual lumen cannula, and a soft reservoir as a pseudo-right atrium. All experiments were conducted at 37°C using an HCU 30 heater-cooling unit and with human blood at a hematocrit of 36%. The blood pressure in the pseudo-right atrium was continuously monitored and maintained at 4-5 mm Hg. For each cannula, pump flow rates and pressures at both the arterial and venous sides were recorded at revolutions per minute (RPMs) from 1750 to 3750 in 250 intervals. For each RPM, six data sets were recorded for a total of 162 data sets. The total volume of the system was 300 mL. The flow range for the 13Fr, 16Fr, and 19Fr cannulae were from 228 to 762 mL/min, 478 to 1254 mL/min, and 635 to 1754 mL/min, respectively. The pressure drops at the arterial side were higher than the venous side at all tested conditions except at 1750 rpm for the 19Fr cannula. The results of this study showed the flow ranges and the pressure drops of three different sized dual lumen cannulae using human blood, which is more applicable in clinical settings compared with evaluations using water.

The new role of the perfusionist in adult extracorporeal life support.

Adult and pediatric extracorporeal life support (ECLS) has been transformed by the European(1) and Australian( 2) experiences with a reduction of the circuit to its most basic form (Figure 1). Many factors have converged at this point in time to allow us to offer this support. The availability in the U.S.A. of an advanced oxygenator (Quadrox(D)) (Maquet Inc., Bridgewater, NJ), long-term centrifugal pumps and circuit coatings offers us the means to provide ECLS. The other equally important factor is the intensivist trained in extracorporeal therapies. Once the intensive care unit registered nurse (ICU RN) is trained to safely and effectively manage both the patient and ECLS circuit, this support may be offered. The perfusionist is in an unique position to educate and mentor the ICU RN in ECLS. There is, perhaps, no one in a better position to explain this equipment and its uses in an interdisciplinary-oriented pediatric and adult ECLS program than a perfusionist.