The Journal of ExtraCorporeal Technology Issue 55-1 | Page 43

J . Blanco-Morillo et al .: J Extra Corpor Technol 2023 , 55 , 30 – 38 35

Table 1 . Description of the covariate analysis .

Abbreviations : Ao : Aortic ; BSA : Body Surface Area ; CABG : Coronary Artery Bypass Graft ; DM : Diabetes Mellitus ; ICU : Intensive Care Unit ; LVEF : Left Ventricular Ejection Fraction ; Val : Valvular . Inconsistent data between different records were considered missing . * p-value < 0.05 .

Table 2 . Balancing of preoperative variables .

Abbreviations : Ao : Aortic ; BSA : Body Surface Area ; PrevHct : preoperative hematocrit ; LVEF : Left Ventricular Ejection Fraction ; DM : Diabetes Mellitus ; PStroke : preoperative stroke ; Val : valvular ; CABG : Coronary Artery Bypass Graft ; Mix : combined surgery ; Ao : aorta ; PrevCrea : preoperative creatinine . No significant differences were found ( lowest p-value was Surgery : CABG = 0.33 ).

factor against emboli , reducing the embolic load delivered to the patient during CPB and the exposure to high embolic volumes [ 20 ]. Some authors pointed out that GME and sudden hemodilution play a major role in the aggression to endothelial glycocalyx , resulting in microvascular impairment , hypoperfusion , inflammatory response , and end-organ dysfunction [ 21 – 24 ].

However , current evidence supporting the individual benefits of the CPB initiation with an empty venous line or VAVD , in terms of enhanced recovery , is also poor [ 1 , 25 , 26 ]. Otherwise , our observations indicate that when all these techniques are combined in the standardized procedure described as HAR , priming hemodilution and BPR until hospital discharge are reduced until hospital discharge , representing a significant effect on the recovery . In terms of mechanical ventilation and ICU stay our study seems to be aligned with current evidence pointing out that exposure to sudden haemodilution during CPB is directly associated with the incidence of endothelial dysfunction , inflammatory response , and renal injury [ 22 , 24 , 27 ]. Some evidence indicates that MiECC application may reduce mechanical ventilation time , ICU length of stay , inflammatory response , cytokine release , and total stay [ 28 – 30 ].

Lower exposure to BPR and anemia are also related to lower postoperative morbidity and mortality [ 31 – 33 ]. However , our preliminary study only was able to observe that HAR applications did not represent significant differences in postoperative morbidity and bleeding , but a marked tendency to reduce inhospital mortality by seven points was observed ( p = 0.056 ). In this regard , we consider that the protective effect of the procedure could have been underestimated by the adoption of strict exclusion criteria , that eliminated redo cases , to improve the accuracy in measuring the effect on BPR .

Under an economic scope , HAR does not seem to represent any additional cost . Moreover , when applied to high-risk patients , just computing the direct cost of one unit when the exposure was avoided , the minimum unburdened savings exceeded 580 $/ patient [ 34 ]. However , burdened costs of transfusion and ICU stay also include expenses like human resources , machinery , facility maintenance , transport , storage , side effects , and follow-up costs which should be considered [ 35 ]. Thereby , according to other authors [ 36 – 39 ], the saving per patient treated with HAR may reach the amount of 2741.94 $ ( Table 5 ).

Several limitations should be considered in this preliminary study . Although the application of a PSM to estimate the causal effects of treatments can reduce the effect of biases when