Outcome Improvement and Cost Reduction in an Increasingly Morbid Cardiac Surgery Population

Correlation of Near-Infrared Spectroscopy Oximetry and Corresponding Venous Oxygen Saturations in Children with Congenital Heart Disease

Invasive and non-invasive monitoring allow for early detection of hemodynamic compromise, facilitating timely intervention and avoidance of further decline. While venous oximetry is useful for assessing the adequacy of systemic oxygen delivery (DO₂), it is most often intermittent, invasive, and costly. Near-infrared spectroscopy (NIRS) oximetry allows for the non-invasive estimation of the adequacy of DO₂. We assessed the correlation between cerebral NIRS oximetry and superior vena cava (SVC) and jugular venous (JV) oxygen saturations and between renal NIRS oximetry and inferior vena cava (IVC) oxygen saturations. Systematic review of the literature was conducted to identify studies with data regarding near-infrared spectroscopy and venous saturation. The PubMed, EMBASE, Medline, and Cochrane databases were queried using the following terms in isolation and various combinations: "congenital heart disease," "near infrared spectroscopy," "venous saturation," and "pediatric." Pediatric studies in which simultaneous NIRS oximetry and corresponding venous oxygen saturations were simultaneously collected after cardiac surgery or catheterization were identified. Data were pooled from these studies to analyze the correlation between NIRS oximetry and the corresponding venous oxygen saturations. A total of 16 studies with 613 patients were included in the final analyses. Data were present to compare cerebral and renal NIRS oximetry with corresponding venous oxygen saturation. Cerebral NIRS and SVC and JV oxygen saturations and renal NIRS and IVC oxygen saturations demonstrated strong degrees of correlation (r-value 0.70 for each). However, cerebral NIRS and IVC oxygen saturation had a week degree of correlation (r-value of 0.38). Pooled analyses demonstrate that cerebral NIRS oximetry correlates strongly with SVC or JV oxygen saturation while renal NIRS oximetry correlates strongly with IVC oxygen saturations. A weak correlation was noted between cerebral NIRS oximetry and IVC oxygen saturations.

[How can we define the extracorporeal circulation quality?]

Extracorporeal circulation (ECC) has to ensure homeostasis of the patient and to minimize pathophysiological disorders inherent in the technique. However, we cannot dissociate it from the surgery and anesthesia knowing that the discipline involves a close partnership with these stakeholders. The purpose of this publication is to review the essential elements that at present can contribute to the quality of the CEC and suggest improvements and developments to be implemented in this area.

Why do patients having coronary artery bypass grafts have different costs or length of stay? An analysis across 10 European countries

We analyse variations in cost or length of stay (LoS) for 66,587 patients from 10 European countries receiving a coronary artery bypass graft (CABG) procedure. In five of these countries, variations in cost are analysed using log-linear models. In the other five countries, negative binomial regression models are used to explore variations in LoS. We compare how well each country's diagnosis-related group (DRG) system and a set of patient-level characteristics explain these variations. The most important explanatory factors are the total number of diagnoses and procedures, although no clear effects are evident for our CABG-specific diagnostic and procedural variables. Wound infections significantly increase LoS and costs in most countries. There is no evidence that countries using larger numbers of DRGs to group CABG patients are better at explaining variations in cost or LoS. However, refinements to the construction of DRGs to group CABG patients might recognise first and subsequent CABGs or other specific surgical procedures, such as multiple valve repair.

Monitoring tissue oxygenation by near infrared spectroscopy (NIRS): background and current applications

Conventional cardiovascular monitoring may not detect tissue hypoxia, and conventional cardiovascular support aiming at global hemodynamics may not restore tissue oxygenation. NIRS offers non-invasive online monitoring of tissue oxygenation in a wide range of clinical scenarios. NIRS monitoring is commonly used to measure cerebral oxygenation (rSO(2)), e.g. during cardiac surgery. In this review, we will show that tissue hypoxia occurs frequently in the perioperative setting, particularly in cardiac surgery. Therefore, measuring and obtaining adequate tissue oxygenation may prevent (postoperative) complications and may thus be cost-effective. NIRS monitoring may also be used to detect tissue hypoxia in (prehospital) emergency settings, where it has prognostic significance and enables monitoring of therapeutic interventions, particularly in patients with trauma. However, optimal therapeutic agents and strategies for augmenting tissue oxygenation have yet to be determined.

[Bedside thrombelastography. Cost reduction in cardiac surgery]

BACKGROUND

Demographic changes and aggressive medication with platelet aggregation inhibitors have resulted in a marked increase in blood and coagulation product expenditure and costs in cardiac surgery. We analyzed the bedside coagulation test (ROTEM) in order to verify clot forming quality and to find a cost-effective treatment algorithm.

PATIENTS AND METHODS

Annual treatment costs of all cardiosurgical patients were retrospectively analyzed before (729 patients) and after (693 patients) implementation of the bedside ROTEM test. Cumulative numbers and costs of platelet concentrates (PltC), fresh frozen plasma (FFP), red blood cell units (RBC), and the coagulation factors prothrombin complex concentrates (PCC), recombinant factor VIIa (rFVIIa), factor XIII (FXIII), and fibrinogen were assessed. Average monthly numbers and costs were compared. The number of rethoracotomies and early mortality were assessed and compared in both periods.

RESULTS

After ROTEM implementation cumulative RBC expenditure showed a 25% decrease and PltC a 50% decrease. FFP expenditure remained unchanged. PCC, FXIII were markedly reduced (-80%) while rFVIIa was entirely omitted. Fibrinogen, however, showed a two-fold increase. Cumulative average monthly costs of all blood products decreased from 66,000 EUR to 45,000 EUR (-32%). Coagulation factor average monthly costs decreased from 60,000 EUR to 30,000 EUR (-50%) yielding combined savings of 44%. In contrast, average monthly costs for ROTEM were 1,580 EUR. The total number of rethoracotomies decreased from 6.6% to 5.5% while early mortality (5.9%; 6.0%) remained stable.

CONCLUSIONS

Cumulative costs for treatment of perioperative coagulation disorders were reduced by bedside ROTEM analysis to achieve a selective substitution management. Saved costs for blood and coagulation products clearly outweighed the expenses of ROTEM. Adequate differential coagulation management can therefore be cost-effective.