Does the type of cardioplegia used during valve surgery influence operative nadir hematocrit and transfusion requirements?

Implementation of a Prescriptive Extracorporeal Circuit and Its Effect on Hemodilution and Blood Product Usage during Cardiac Surgery

The use of cardiopulmonary bypass (CPB) contributes significantly to intraoperative anemia. The use of a prescriptive circuit that is tailored to the patient size could significantly reduce priming volumes, resulting in less hemodilution. The purpose of this study was to determine whether a prescriptive circuit resulted in decreased hemodilution, reduced blood product usage, and improved outcomes. In total, 204 patients prospectively received the prescriptive protocol between March 2019 and November 2019. This protocol was composed of three circuit sizes: small [body surface area (BSA) ≤ 1.85 m²], medium (BSA 1.86-2.30 m²), and large (BSA ≥ 2.31 m²). Data for CPB and post-bypass transfusions were collected, along with postoperative outcomes. These patients were then 1:2 propensity score matched to 401 patients who were retrospectively reviewed who had undergone cardiac surgery using a one-sized CPB circuit. The prescriptive protocol cohort had more patients with renal disease, whereas the conventional cohort had more history of hypertension. Intraoperative results show the prescriptive circuit had lower mean prime volume and total prime volume after reverse autologous prime (1,084 mL vs. 1,798 mL, p < .0001; 725 mL vs. 1,181 mL, p < .0001). Ultrafiltration was higher in the prescriptive group (872 vs. 645 mL, p < .0001), which likely balanced the increased use of del Nido cardioplegia in the prescriptive group (1,295 vs. 377 mL, p < .0001). The drop in hematocrit (HCT) from baseline was less in the prescriptive group (15.1 ± 4.91 vs. 16.2 ± 4.88, p = .0149), whereas the postoperative HCT was higher (32.79 ± 4.88 vs. 31.68 ± 4.99, p = .0069). Transfusion of packed red cells did not change between the two groups. Implementation of a prescriptive circuit did not reduce on-bypass or intraoperative blood product usage. However, there was a significant reduction in on-bypass hemodilution and increased postoperative HCT.

A proposed redosing interval of del Nido cardioplegia solution in adult cardiac surgery: a propensity-matched study

Background:

Recently, del Nido cardioplegia solution (DN) has been utilized in adult cardiac surgery. However, adequate interval of maintenance dose(s) is still unclear. The purpose of this study was to assess the safety and efficacy of our DN protocol by comparing with conventional cold whole blood cardioplegia (CWB).

Methods:

A total of 1003 consecutive patients (DN group, N = 350 vs. CWB group, N = 653) underwent cardiovascular surgery between July 2013 and September 2018 were included in this study. The DN protocol was to administer 1000 to 1200 ml as an initial dose and to add maintenance dose(s) (500 ml each) every 60 minutes when the estimated cross-clamp time was over 90 minutes. CWB was given every 20 minutes, regardless of cross-clamp time. Propensity matching identified 254 matched pairs for analysis. The preoperative and postoperative data were reviewed.

Results:

Cross-clamp time was significantly shorter in the DN group compared with the CWB group (107 ± 56 minutes vs. 116 ± 49 minutes, p = 0.0458). A retrograde cannula was used in 124 (48.8%) patients in the DN group and 181 (71.3%) patients in the CWB group (p < 0.0001). There were no significant differences in requiring postoperative cardiac supports (inotropes, mechanical circulatory supports) and major complications. In-hospital mortality was similar between two groups (DN group: 3.2% vs. CWB group: 2.4%, p = 0.5872).

Conclusions:

Short-term clinical outcomes in the patients underwent cardiovascular surgery with the DN protocol including the redosing interval strategy were acceptable. Also, DN protocol was associated with shortened cross-clamp time and less usage of the retrograde cannula.

Alternative technique of long acting cardioplegia delivery results in less hemodilution

BACKGROUND

Preparation of del-Nido cardioplegia and its delivery technique can cause significant hemodilution. The resultant effects from hemodilution are largely proportionate to the use of a dual circuit. We opted for a custom-disposable single cardioplegia circuit instead of a dual circuit.

METHODS

We describe an alternative technique of del-Nido cardioplegia delivery and initial clinical experience with it at National University Hospital, Singapore. This is a retrospective analysis of data from January 2017 to April 2019, comprising of 177 patients of heart surgery and reflecting a single center database survey under the National Health Care Group.

RESULTS

Of the 177 patients who underwent surgery with del-Nido cardioplegia, 76 (42.9%) were valve-only procedures and 5 (2.8%) were coronary artery bypass graft-only procedures. Ultrafiltration was utilized in 132 (62.6%) patients, whereas filtrate volume was 2200 [150-9500] mL. The alternative technique of del-Nido cardioplegia delivery adopted by National University Hospital advocates for a single pump, single circuit system. The retrospective institutional data highlighted safe delivery of del-Nido cardioplegia using this technique in a range of procedures.

CONCLUSION

Besides the safe delivery of del-Nido cardioplegia, the National University Hospital Technique reduces hemodilution and provides other technical benefits including a steeper temperature gradient, modification of circuit configuration to deliver another cardioplegia while on bypass, as well as re-configuration of clamps to spike the base solution.