CDI Blood Parameter Monitoring System 500—A New Tool for the Clinical Perfusionist

In early 2008, surveys of active extracorporeal membrane oxygenation (ECMO) centers in North America were conducted by electronic mail regarding neonatal ECMO equipment and professional staff. Eighty of 103 (78%) North American ECMO centers listed in the Extracorporeal Life Support Organization directory as neonatal centers responded to the survey. Of the responding centers, 82.5% routinely used roller pumps for neonatal ECMO, and the remaining 17.5% used centrifugal pumps. Silicone membrane oxygenators were used by 67% of the respondents, whereas 19% used micro-porous hollow fiber oxygenators, and 14% used polymethylpentene hollow fiber oxygenators. Of the silicone membrane oxygenator users, 86% used the Medtronic Ecmotherm heat exchanger, 10% used the Gish HE-4 heat exchanger, and 4% used the Terumo Conducer device. Sixty-four percent of the responding centers used some form of in-line blood gas monitoring. Six percent of the centers used a bubble trap in the arterial line, and 5% used an arterial line filter. A bladder was used by 85% of the centers, and 4% of these used a mechanical bladder box for servo regulation; the remaining 96% used pressure servo regulation. An air bubble detector was used by 88% of the responding centers. A surface coating was used by 44% of the centers on all their neonatal ECMO patients. Thirty-one percent of the centers use an activated clotting time of 180–220 seconds. At 54% of the responding centers, perfusionists were involved with the ECMO program, registered nurses were involved at 70% of the centers, and respiratory therapists were involved at 46% of the centers. Compared with a 2002 survey, silicone membrane use is declining, and the use of centrifugal blood pumps and coated ECMO circuits is becoming more apparent. ECMO teams are still multidisciplinary, made up of combinations of registered nurses, respiratory therapists, and perfusionists.

Section: Discussionmentioning

confidence: 99%

North American Neonatal Extracorporeal Membrane Oxygenation (ECMO) Devices and Team Roles: 2008 Survey Results of Extracorporeal Life Support Organization (ELSO) Centers

Lawson

Lawson²,

Walczak³

et al. 2008

Use of the CDI Blood Parameter Monitoring System 500 for Continuous Blood Gas Measurement During Extracorporeal Membrane Oxygenation Simulation

Schreur

Niles²,

Ploessl³

2005

The Oximetrix III Opticath (Abbott Critical Care Systems) is used for continuous measurement of venous saturation in a variety of applications, including extracorporeal membrane oxygenation (ECMO), despite clinical reports that have presented data showing poor accuracy of these devices. The CDI Blood Parameter Monitoring System 500 (Terumo) is an inline blood gas monitoring tool commonly used during cardiopulmonary bypass procedures to continuously assess oxygen saturation, blood gases, potassium, and bicarbonate. The purpose of this experiment was to compare the Opticath and the CDI 500 in trending venous blood saturation during a simulation of ECMO. An ECMO simulation circuit consisting of a silicone rubber membrane oxygenator and a stainless steel heat exchanger was constructed, and a standard venous reservoir bag was used to represent the patient. The CDI and the Opticath were incorporated side by side into a shunt that originated just before the oxygenator and returned flow to the venous line. The circuit was primed with fresh porcine blood and conditioned with the addition of CO2 to simulate typical venous blood under ECMO conditions. After an initial calibration procedure, samples were drawn and analyzed by an AVL Opti CCA (Roche/Osmetech) every 4–8 hours for a period of 7 days, with calibration of each device at sample intervals. The data were plotted, and a least squares regression line was calculated. The average error for venous saturation of the CDI and Opticath after 72 hours was 3.86 and 9.51 respectively. At 168 hours, error for the CDI was 8.37, and the Opticath had an error of 14.78. A correlation analysis of the CDI and AVL CCA analyzer yielded a correlation coefficient of r = .88 at 72 hours and r = .84 at 168 hours. Correlation between the Opticath and the AVL CCA yielded a correlation coefficient of r = .77 at 72 hours and r = .55 at 168 hours. Based on these findings, the CDI 500 is an effective tool for monitoring venous blood saturation under simulated conditions of ECMO.

In Vitro Comparison of the New In-Line Monitor BMU 40 versus a Conventional Laboratory Analyzer

Grosse¹,

Holzhey²,

Falk³

et al. 2010

Reliable information about different blood parameters is essential in maintaining hemodynamics, perfusion, and gas exchange during cardiopulmonary bypass (CPB). For this purpose, a precise and continuous monitoring is needed. The objective of this in vitro study was to compare a novel continuous in-line blood parameter monitoring system versus a reference laboratory analyzer. The study was conducted as an in vitro prospective experimental study during a CPB simulation. The reliability of BMU 40 was tested in monitoring the pO2, oxygen saturation (SO2), and hematocrit (Hct) under physiological and extreme conditions with regards to temperature, oxygenation, and blood concentration. Four different tests were performed and conducted with five sensors each. Correlation analyses and Bland-Altman analyses were performed. A total of 350 measurement points were compared. All monitored values of blood parameters correlated highly with laboratory values (all r values >.90). Test 1: Biases of pO2 (act) varied from −3.24 mmHg (±6.86 mmHg) up to 6.0 mmHg (±17.89 mmHg). The biases of pO2 (37°C) ranged from −3.52 mmHg (±6.01 mmHg) up to 68.8 mmHg (±67.82 mmHg). Test 2: The biases standard deviations (SD) for Hct ranged from −0.35% (±.79%) up to 2.35% (±.91%). The biases (SD) for SO2 varied from −.45% (±.86%) up to .85% (±1.01%). Test 3: The biases (SD) of Hct ranged from −1.00% (±1.84%) up to −.67% (±1.49%). Test 4: The biases (SD) for SO2 varied from −.36% (±1.60%) up to.48% (±.90%). The BMU 40 is a reliable device in measuring the partial oxygen pressure (pO2), SO2, and Hct under normal physiological and extreme conditions with regards to temperature, oxygenation, and blood concentration in simulation of CPB. The algorithm to calculate pO2 (37°C) under hypothermic conditions needs to be adjusted. (Before the official market launch a new software version of the BMU 40 has been developed. The algorithm to calculate pO2 (37°C) under hypothermic conditions has been improved and the miscalculation eliminated.)