Continuous blood gas monitoring (CBGM) plays a pivotal role in maintaining patient stability during cardiopulmonary bypass (CPB). Traditional methods rely on intermittent sampling using blood gas analyzers (BGA), which can delay detection of critical fluctuations. This retrospective study assesses the clinical accuracy and reliability of the Quantum Perfusion System (QPS) by Spectrum Medical—an advanced CBGM technology using a cuvette-free, non-invasive setup—compared to standard BGA methods.
The study involved 40 patients undergoing elective cardiac surgeries including coronary artery bypass grafting (CABG), mitral valve replacement (MVR), and aortic valve replacement (AVR). All subjects were monitored continuously using the QPS, and readings were matched against the GEM Premier 5000 BGA at regular 15-minute intervals.
Design and Methodology
Patients enrolled were adults undergoing elective cardiac surgery with CPB at Queen Alia Heart Institute in Jordan. Exclusion criteria included emergency procedures and comorbid conditions such as renal or hepatic failure. QPS was calibrated prior to use and aligned with BGA baseline readings for accuracy.
Continuous monitoring was performed via QPS integrated with Quantum Workstation and Ventilation Modules, using direct probes on PVC tubing. Blood gas parameters were recorded every 15 minutes, with all readings conducted at a controlled temperature of 37°C.
Statistical Evaluation and CLIA Compliance
Key parameters assessed included hemoglobin (Hb), hematocrit (Hct), partial pressure of oxygen (PaO₂), carbon dioxide (PCO₂), mixed venous oxygen saturation (SvO₂), and arterial oxygen saturation (SaO₂). Both pre- and post-alignment measurements fell within the acceptable deviation ranges set by the Clinical Laboratory Improvement Amendments (CLIA):
- Hemoglobin: Pre-alignment deviation 1.9%, post-alignment 0.7% (CLIA threshold ±5%)
- Hematocrit: Pre 2.1%, post 0.2% (±5%)
- PaO₂: Pre 3.9%, post 0.4% (±10%)
- PCO₂: Pre 4.2%, post 0.19% (±10%)
- SvO₂: Pre 3%, post 0.8% (±5%)
- SaO₂: Pre 2.6%, post 0.1% (±5%)
Bland-Altman plots and Passing-Bablok regression confirmed high correlation and minimal bias between QPS and BGA readings. Paired t-tests and Wilcoxon Signed-Rank tests revealed no statistically significant differences, reinforcing the system’s accuracy.
Clinical Implications
The QPS provides real-time data, empowering clinicians to make timely decisions, especially during hemodynamic instability. Traditional BGA sampling introduces delays and risks that can be mitigated through continuous monitoring. Moreover, QPS’s in-line integration avoids the use of disposable cuvettes, reducing consumable costs and simplifying the monitoring process.
This innovation aligns with updated European guidelines for perfusion practices, offering the dual advantage of improving patient outcomes and streamlining clinical workflows.
Operational Efficiency and Economic Considerations
The cuvette-free QPS not only reduces operational costs but also minimizes clinical complexity. Its implementation results in lower labor demands, faster data availability, and improved resource utilization. Maintenance is typically annual, and total costs depend on regional procurement agreements.
Limitations and Future Directions
Despite promising results, the study’s sample size (n=40) limits its generalizability. Further studies across more diverse populations and clinical scenarios are recommended. Future investigations should explore the system’s utility during prolonged CPB durations and in patients with unstable hemodynamics. Additionally, feedback from surgical and perfusion teams can guide usability improvements and enhance clinical integration.
Conclusion
The Quantum Perfusion System emerges as a reliable and accurate tool for real-time blood gas monitoring during CPB. By meeting CLIA accuracy standards and demonstrating non-inferiority to traditional BGA, QPS offers substantial clinical, economic, and operational benefits. Though currently recommended as a trending device, further validation in larger, multi-center trials could support its broader adoption in cardiac surgical care.
