2021 MiECTiS focused update on the 2016 position paper for the use of minimal invasive extracorporeal circulation in cardiac surgery

The landmark 2016 Minimal Invasive Extracorporeal Technologies International Society (MiECTiS) position paper promoted the creation of a common language between cardiac surgeons, anesthesiologists and perfusionists which led to the development of a stable framework that paved the way for the advancement of minimal invasive perfusion and related technologies. The current expert consensus document offers an update in areas for which new evidence has emerged. In the light of published literature, modular minimal invasive extracorporeal circulation (MiECC) has been established as a safe and effective perfusion technique that increases biocompatibility and ultimately ensures perfusion safety in all adult cardiac surgical procedures, including re-operations, aortic arch and emergency surgery. Moreover, it was recognized that incorporation of MiECC strategies advances minimal invasive cardiac surgery (MICS) by combining reduced surgical trauma with minimal physiologic derangements. Minimal Invasive Extracorporeal Technologies International Society considers MiECC as a physiologically-based multidisciplinary strategy for performing cardiac surgery that is associated with significant evidence-based clinical benefit that has accrued over the years. Widespread adoption of this technology is thus strongly advocated to obtain additional healthcare benefit while advancing patient care.

Individualized heparin monitoring and management reduces protamine requirements in cardiac surgery on minimal invasive extracorporeal circulation; A prospective randomized study

INTRODUCTION

Individualized heparin and protamine management is increasingly used as a strategy to reduce coagulation activation and bleeding complications. While it is associated with increased heparin requirements during Cardiopulmonary Bypass (CPB), the impact on protamine administration remains controversial. We aim to investigate the effect of heparin level-guided monitoring on protamine dosing during cardiac surgery where low-anticoagulation protocols are implemented.

METHODS

This is a prospective, randomized, controlled trial. A total of 132 patients undergoing elective full-spectrum cardiac surgery with Minimal Invasive Extracorporeal Circulation (MiECC) were recruited. All patients were managed by the same anaesthetic, surgical and perfusion team. Patients were randomly allocated in two groups; the individualized heparin-protamine titration (IHPT) group and the conventional heparinization and reversal group by using ACT (cACT) with a 0.75:1, protamine: heparin ratio. Titration was accomplished with the Hepcon HMS Plus (Medtronic, Minneapolis, MN) system. The primary outcome of the study was the total protamine dose used. Secondary outcomes comprised of the total heparin dose, the percentage of patients achieving target ACT, 24-h transfusion requirements, postoperative bleeding, duration of mechanical ventilation, major morbidity and length of hospital stay. Patients in each group were divided in two subgroups according to the target ACT; those operated for coronary artery bypass grafting (CABG) using a target ACT >300 s and the rest (non-CABG) patients operated with a target ACT >400 s, respectively.

RESULTS

Protamine requirements were significantly reduced when IHPT was implemented; CABG (118 ± 24 mg vs 163 ± 61 mg; p < 0.001) and non-CABG cases (151 ± 46 mg vs 197 ± 45 mg; p < 0.001). Moreover, heparin requirements were significantly higher in the non-CABG subgroup managed with IHPT (34,539 ± 7658 IU vs 29,893 ± 9037 IU; p = 0.02). In overall, no significant differences were detected with respect to postoperative bleeding, transfusion of RBC or other blood products.

CONCLUSIONS

Individualized heparin monitoring and management reduces protamine requirements in cardiac surgery with MiECC implementing reduced anticoagulation strategy.

TRIAL REGISTRATION

clinicaltrials.gov; NCT04215588.

Modular minimally invasive extracorporeal circulation ensures perfusion safety and technical feasibility in cardiac surgery; a systematic review of the literature

INTRODUCTION

Despite extensive evidence that shows clinical of superiority of MiECC, worldwide penetration remains low due to concerns regarding air handling and volume management in the context of a closed system. The purpose of this study is to thoroughly investigate perfusion safety and technical feasibility of performing all cardiac surgical procedures with modular (hybrid) MiECC, as experienced from the perfusionist's perspective.

METHODS

We retrospectively reviewed perfusion charts of consecutive adult patients undergoing all types of elective, urgent, and emergency cardiac surgery under modular MiECC. The primary outcome measure was perfusion safety and technical feasibility, as evidenced in the need for conversion from a closed to an open circuit. A systematic review of the literature was conducted aiming to ultimately clarify whether there are any safety issues regarding MiECC technology.

RESULTS

We challenged modular MiECC use in a series of 403 consecutive patients of whom a significant proportion (111/403; 28%) underwent complex surgery including reoperations (4%), emergency repair of acute type A aortic dissection and composite aortic surgery (1.7%). Technical success rate was 100%. Conversion to an open circuit was required in 18/396 patients (4.5%), excluding procedures performed under circulatory arrest. Open configuration accounted for 40% ± 21% of total procedural perfusion time and was related to significant hemodilution and increase in peak lactate levels. Systematic review revealed that safety of the procedure challenged originated from a single report, while no clinical adverse event related to MiECC was identified.

CONCLUSIONS

Use of modular MiECC secures safety and ensures technical feasibility in all cardiac surgical procedures. It represents a type III active closed system, while its stand-by component is reserved for a small (<5%) proportion of procedures and for a partial procedural time. Thus, it eliminates any safety concern regarding air handling and volume management, while it overcomes any unexpected intraoperative scenario.

Minimal invasive extracorporeal circulation preserves coagulation integrity

INTRODUCTION

Coagulopathy after cardiac surgery is a serious multifactorial complication that results in postoperative bleeding requiring transfusion of red blood cells and procoagulant products. Use of cardiopulmonary bypass represents the major contributing factor affecting coagulation. We sought to prospectively investigate the effect of contemporary minimal invasive extracorporeal circulation (MiECC) on coagulation parameters using point-of-care (POC) rotational thromboelastometry and the relation to postoperative bleeding.

METHODS

Patients undergoing elective cardiac surgery on MiECC were prospectively recruited. Anticoagulation strategy was based on individualized heparin management and heparin level-guided protamine titration. Rotational thromboelastometry testing was performed before induction of anesthesia and after aortic cross-clamp release. A strict POC-guided transfusion protocol was implemented. The primary endpoint was the assessment of viscoelastic properties of the coagulating blood at the end of surgery compared to preoperative values and the relation to postoperative bleeding and 24-hour transfusion requirements.

RESULTS

Fifty patients were included in the study with a significant proportion having complex surgery. Thirteen patients (26%) required blood transfusion (mean rate: 0.5 ± 1 units per patient), 5/50 (10%) received coagulation factors while no patient received fresh frozen plasma, platelets or fibrinogen. Thromboelastometry analysis showed that the major derangement was CT EXTEM > 100 seconds in 28/50 (56%) and A10 EXTEM < 40 mm in one (2%) patient without clinical significance. Platelet function was preserved throughout surgery. A10-FIBTEM was found predictive of postoperative bleeding at 12 hours.

CONCLUSIONS

MiECC preserves clot quality throughout surgery acting in both key determinants of clot strength; fibrinogen and platelets. This is clinically translated into minimal postoperative bleeding and restricted use of blood products and coagulation factors.

Cardiopulmonary bypass-induced coagulopathy in pediatric patients: The role of platelets in postoperative bleeding. A preliminary study

Pediatric patients are particularly prone to cardiopulmonary bypass (CPB)-induced coagulopathy mainly due to hemodilution, consumption of coagulation factors and hypothermia. The aim of the present study was to examine the possible role of platelet count and function as it relates to the bleeding risk after CPB in the pediatric population. All consecutive patients (age <13 years) scheduled for elective cardiac surgery between January 2019 and November 2019 were retrospectively considered for the study. We gathered demographic characteristics, perioperative laboratory data (mainly platelet count and function), transfusion requirements, and blood loss for each patient. Patients with a chest tube output during the first 24 hours after surgery >75th percentile were bleeders (cases). Controls were nonbleeders. A total of 31 patients were enrolled [median age 17 (4-57) months]. A significant postoperative reduction in platelet count (P < .001) and function either in ADP-test (P < .001), TRAP-test (P < .001) and ASPI-test (P < .001) was found, with positive correlations between chest tube output within the first 24 hours after surgery and postoperative impairment of platelet count (R = 0.553, P = .001), ADP-test (R = 0.543, P = .001), TRAP-test (R = 0.627, P < .001) and ASPI-test (R = 0.436, P = .014). Eight children (26%) experienced major postoperative bleeding. Bleeders were significantly younger (P = .015) and underwent longer CPB duration (P = .015). Despite no significant differences in postoperative platelet count and function between cases and controls, the postoperative reduction (Δ) in platelet count (P = .002) and function in ADP-test (P = .007), TRAP-test (P = .020) and ASPI-test (P = .042) was significantly greater in bleeders vs. nonbleeders. A ΔPLT >262 500 ×10⁹ /L, a ΔADP-test >29 U, a ΔTRAP-test >44 U and a ΔASPI-test >26 U showed to be predictive of major postoperative bleeding. Postoperative bleeding in children undergoing cardiac surgery with CPB was linked to younger age, longer CPB duration, and significant postoperative reduction in platelet count and function. Larger studies are needed to confirm our results and define strategies to reduce postoperative bleeding in these patients.

The effect of the relationship between post-cardiotomy neutrophil/lymphocyte ratio and platelet counts on early major adverse events after isolated coronary artery bypass grafting

Background

In this study, we aimed to investigate the role of postcardiotomy neutrophil, lymphocyte, and platelet counts in predicting major adverse events after coronary artery bypass grafting.

Methods

A total of 373 patients (257 males, 116 females; median age 63, range 33 to 85 years) who underwent isolated coronary artery bypass grafting under cardiopulmonary bypass between January 2015 and January 2020 were retrospectively analyzed. The patients who did not develop any postoperative major adverse event were included in Group 1, while those who did constituted Group 2. Preoperative neutrophil-to-lymphocyte ratio, postcardiotomy neutrophil-to-lymphocyte ratio, postoperative Day 1 neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio were calculated.

Results

Preoperative neutrophil counts, C-reactive protein values, neutrophilto- lymphocyte ratio, total perfusion time, and length of intensive care unit and hospital stay were significantly higher in Group 2 (p=0.019, p=0.028, p<0.001, p=0.027, p<0.001, and p<0.001, respectively). Post-cardiotomy neutrophil, neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio, along with the postoperative first day white blood cell count, neutrophil, C-reactive protein, neutrophil-to-lymphocyte ratio, and neutrophil-to-lymphocyte x platelet ratio were significantly higher in Group 2 (p=0.004, p<0.001, p<0.001, p=0.019, p=0.003, p=0.001, p<0.001, and p=0.041, respectively). The post-cardiotomy platelet and lymphocyte counts and postoperative first day lymphocyte counts were significantly lower in Group 2 (p<0.001, p=0.007, and p=0.009, respectively).

Conclusion

Post-cardiotomy neutrophil-to-lymphocyte ratio and neutrophilto- lymphocyte x platelet ratio can be easily accessible, inexpensive complete blood count parameters and may be more valuable in predicting major adverse events in patients undergoing coronary artery bypass grafting.