Retrograde autologous priming to reduce allogeneic blood transfusion requirements: a systematic review

Effectiveness of the vacuum assisted aspiration AngioVac system in the removal of intravascular masses

BACKGROUND

Invasive procedures used to manage intravascular masses such as vegetation from endocarditis, deep vein thrombosis, and septic emboli are associated with high rates of complications and mortality, especially in patients with several pre-existing comorbidities. A minimally invasive technique that has become more popular in recent years is the AngioVac procedure. This single-centered, retrospective study focuses on patient presenting comorbidities and indications for the procedure as well as postprocedural outcomes.

METHODS

A total of 33 patients who underwent an AngioVac procedure at Sanford Health between March 2014 and October 2019 was reviewed. Data were collected on pre-existing comorbidities, indication of procedure, length of stay, and postoperative outcomes.

RESULTS

We evaluated a total of 33 patients who underwent an AngioVac procedure for removal of intravascular mass. The most common indications for the procedure were endocarditis (24/33, 73%); intracardiac mass (5/33, 15%); and deep vein thrombosis or pulmonary embolism (2/33, 6%). Post-procedural blood transfusion was required in nearly half (15/33, 45%). Almost all patients (31/33, 94%) required intraoperative vasopressor use. Nearly all patients (32/33, 97%) were directed to the intensive care unit following the procedure with an average length of stay of 8 days (interquartile range: 3-13). Most common complications seen after the procedure were shock requiring vasopressors, (13/33, 39%), pleural effusion (9/33, 27%), and sepsis (4/33, 12%). Procedural success in this single-centered experience was 85% (28/33), which was defined as size reduction of the initial vegetation by >50% in the absence of severe intraoperative complications and absence of need for further valvular surgical intervention.

CONCLUSION

For surgically high-risk patients, the AngioVac procedure may offer a less invasive option in the management of right sided endocarditis requiring vegetation debulking, intravascular thrombi or cardiac masses.

Hematic Antegrade Repriming: A Reproducible Method to Decrease the Cardiopulmonary Bypass Insult

The current practice of cardiopulmonary bypass (CPB) requires a preoperative priming of the circuit that is frequently performed with crystalloid solutions. Crystalloid priming avoids massive embolism but is unable to eliminate all microbubbles contained in the circuit. In addition, it causes a sudden hemodilution which is correlated with transfusion requirements and an increased risk of cognitive impairment. Several repriming techniques using autologous blood, collectively termed retrograde autologous priming (RAP), have been demonstrated to reduce the hemodilutional impact of CPB. However, the current heterogeneity in the practice of RAP limits its evidence and benefits. Here, we describe hematic antegrade repriming as an easy and reliable method that could be applied with any circuit in the market to decrease transfusion requirements, emboli, and inflammatory responses, reducing costs and the impact of CPB on postoperative recovery.

Adult cardiopulmonary bypass in Australian and New Zealand public hospitals: A survey of practice

A telephone survey of cardiac anaesthetists and perfusionists at the 29 public hospitals providing adult cardiac surgical services in Australia and New Zealand was carried out between December 2019 and January 2020. The aim was to investigate current practice with regard to selected contentious elements of anaesthetic and perfusion management during cardiopulmonary bypass; primarily relating to bypass circuit priming, blood conservation methods and point-of-care coagulation testing. There was a 100% response rate. The average number of adult public cardiopulmonary bypass cases per hospital was 508 (160-1400). For cardiopulmonary bypass cases, ten hospitals (34%) routinely used a cell saver and the remainder used a cell saver selectively. Residual blood remaining in the cardiopulmonary bypass circuit was processed using a cell saver routinely in four hospitals (14%) and selectively in 23 (79%). Acute normovolaemic haemodilution was rarely used. Retrograde autologous priming was used routinely in seven hospitals (24%) and selectively in 16 (55%). All hospitals had access to point-of-care coagulation testing. The majority of hospitals targeted an activated clotting time of 480 s (range 400-500 s) prior to commencing cardiopulmonary bypass. There was marked geographic variation in access to fibrinogen concentrate. The cardiopulmonary bypass circuit prime solution was primarily a balanced crystalloid in most hospitals; however, there was significant variation regarding the addition of human albumin, mannitol, sodium bicarbonate and other medications. Many of the interventions examined were used on a case-by-case basis. These findings support the need for further research to define more evidence-based practice of these interventions.