Utilizing retrograde autologous priming for blood conservation in cardiac surgery.

BACKGROUND: The use of crystalloid priming for extracorporeal circuit in adult cardiac surgery causes inevitable haemodilution. The haemodilution can be reduced by using methods such as retrograde autologous priming (RAP) with the patient's blood. This study compares the RAP technique with standard priming with regards to safety and the impact on haemodilution. METHODS: This was a retrospective cohort study between a control group (n = 100) consisting of consecutive patients undergoing first time isolated coronary artery bypass surgery (CABG) with crystalloid priming solution in the circuit, and the RAP group (n = 100) consisting of patients undergoing isolated first time CABG with the RAP method. All demographics, procedure and perfusion data were gathered from the local surgical and perfusion database. RESULTS: Despite starting with comparable mean pre-operative haemoglobin (Hb) levels (control 127 mg/dL versus RAP 129 mg/dL), the RAP group had significantly higher mean post-op Hb level (109 mg/dL versus 92 mg/dL, P < 0.01). Crystalloid use was also significantly lower in RAP group (3.15 L versus 4.17 L P < 0.02). Freedom from red blood cell transfusion (86% versus 76% P = 0.038) and freedom from blood products (78% versus 66%, P = 0.032) was also significantly better in the RAP group. CONCLUSIONS: This study demonstrates that retrograde autologous priming is a safe and effective method for priming the cardiopulmonary bypass circuit in adult cardiac surgery, with significantly beneficial effects on transfusion rates and intra operative fluid requirements. Given these results the RAP method should be considered as a routine step in priming an extracorporeal circuit for adult cardiac operations.

Stress Ulcer Prophylaxis in Cardiac Surgery: A Retrospective Cohort Study to Analyze the Effects of SUP Cessation.

INTRODUCTION: Upper gastrointestinal bleeding (UGIB) is an important complication among critically ill adults, especially those having cardiac surgery as management is complicated by the requirement for antiplatelet/anticoagulant therapy. As a result, stress ulcer prophylaxis (SUP) has become routine practice in many centers, utilizing either proton pump inhibitors (PPIs) or histamine-2 receptor blockers (H2RBs). Recent evidence from the PEPTIC trial indicated an increase in mortality risk among cardiac surgery patients receiving PPIs compared to H2RBs. Considering these findings, alongside practical difficulties surrounding the transition to H2RBs as a prophylactic agent in New Zealand, Wellington Hospital intensive care unit elected to discontinue routine PPI use for SUP in cardiac surgery patients. A retrospective study was conducted to assess patient outcomes following the discontinuation of routine SUP. METHOD: A retrospective cohort study was conducted of all adult patients who underwent cardiac surgery at Wellington Hospital between February/2018 and January/2022, and divided patients into cohorts before and after the discontinuation of routine use of SUP on the 31st of January 2020. The primary outcomes were the rate of UGIB, oesophagogastroduodenoscopy (OGD) and 180-day postoperative mortality. Secondary outcomes included rates of postoperative Clostridium difficile enteritis, pneumonia, deep sternal wound infection, and length of stay of the index admission. RESULTS: The rate of UGIB statistically significantly increased since the cessation of routine SUP in January 2020 (2.4% vs 5.4%, P-value = .004). This finding was mirrored with the increased rates of OGD (1.9% vs 4.0%, P-value = .005). There were no significant changes in 180-day mortality, hospital length of stay, or any of the postoperative infective complications analyzed, pneumonia, deep sternal wound infection, or C difficile enteritis. CONCLUSION: This study suggests an association between routine use of SUP and reduced rates of clinically significant UGIB and OGD requirements in cardiac surgery patients without increasing risk of infective complications or postoperative mortality.

Case Series of Early Structural Valve Deterioration of Trifecta Bioprosthesis - New Zealand Experience.

PURPOSE: Structural valve deterioration (SVD) remains a limitation on the use of bioprosthetic valves, with patient and valve-related factors contributing to early SVD. The Trifecta valve has been reported to have excellent hemodynamics but studies have highlighted early failure. We present a review and case series at a New Zealand tertiary hospital defining early SVD as failure within 3 years of implant. METHODS: A retrospective review from January 2015 to July 2019 included 525 patients undergoing surgical aortic valve replacement with 263 patients receiving an Abbott Trifecta or Trifecta Glide Technology (GT) valve. Our review found an acceptable safety profile for the valve with excellent hemodynamics, with a low mortality, stroke, and permanent pacemaker rate. RESULTS: Three patients out of 263 were identified from the study period as having early SVD requiring reintervention within 3 years of valve implantation leading to a 1.14% failure rate. One of the valves that had early SVD was a new generation Trifecta GT. An additional four patients were identified to have valves implanted prior to the study period and had valve failure at greater than 3 years post implantation. Five cases had cusp tears as their mechanism of failure, raising concerns about durability. CONCLUSION: The Trifecta valve has an acceptable safety profile and offers good hemodynamics due to the externally mounted leaflets. However, our experience of early SVD and failure is concerning for valve durability. Further comparison to other bioprosthetic valves and longer term follow-up are required to characterize the mechanism of failures.

The Effects of the COVID-19 Pandemic on Cardiac Surgery Volumes and Outcomes in New Zealand.

AIM: New Zealand adopted an "elimination strategy" in response to the 2020 COVID pandemic with strict early border controls and early national lockdowns. The international experience of cardiac surgery provision during the COVID pandemic was of reduced case numbers, difficulties with the provision of elective surgery and in some cases increased morbidity associated with waiting for surgery and from developemnt of the infection in post operative patients. We aim to review the effects the COVID-19 pandemic has had on adult cardiac surgery volumes and outcomes in the Wellington region. METHOD: Utilising local data submitted to the New Zealand National cardiac surgical database, we analysed all cardiac operations completed at a tertiary cardiothoracic centre between January 1st 2019 till December 31st 2020. The COVID-19 lockdown period (March-April 2020) was compared with its' 2019 counterpart as well as the sequential months to analyse for any 'rebound' effect. Number of surgeries, proportion of elective cases, and surgery type were assessed. RESULTS: The lockdown period of March-April/2020 showed a higher number of cardiac surgery cases per month compared to a the same period in  2019 (48.5 vs 39.0 cases/month, P=0.74). A surge in acute cases was noted in September-December 2020 with 57 acute operations completed, compared to 23 for the corresponding time period in 2019. CONCLUSION: The New Zealand response to the COVID pandemic resulted in low relative rates of community transmission and only a small number of patients admitted to hospital.  We did not see a reduction in routine cardiac operations or changes in clincial outcome over this period. Despite the lockdown period, due to low numbers of community and COVID cases in our ICU and hospital we were able to maintain a full operating capacity throughout. We did observe an increase in acute cases following the lockdown likely due to the reduced access to routine cardiology clinics and deferrable diagnostic services.