Cardiovascular Surgery Patients Research Articles

Intraoperative central venous pressure during cardiopulmonary bypass is an alternative indicator for early prediction of acute kidney injury in adult cardiac surgery

BackgroundThe relationship between venous congestion in cardiopulmonary bypass (CPB) and acute kidney injury (AKI) in cardiac surgery has not utterly substantiated. This study aimed at investigate the relationship between CVP in CPB and the occurrence of AKI.MethodsWe retrospectively reviewed 2048 consecutive patients with cardiovascular disease undergoing cardiac procedure with CPB from January 2018 to December 2022. We used the median CVP value obtained during CPB for our analysis and patients were grouped according to this parameter. The primary outcomes were AKI and renal replacement therapy(RRT). Multivariable logistic regression was used to explore the association between CVP and AKI.ResultsA total of 2048 patients were enrolled in our study and divided into high CVP group (CVP ≥ 6.5 mmHg) and low CVP group (CVP < 6.5 mmHg) according to the median CVP value. Patients in high CVP group had the high AKI and RRT rate when compared to the low CVPgroup[(367/912,40.24%)vs.(408/1136,35.92%),P = 0.045;(16/912,1.75%vs.9/1136;0.79%), P = 0.049]. Multivariate logistic regression analysis displayed CVP played an indispensable part in development of renal failure in surgical.ConclusionsElevated CVP(≥ 6.5mmH2OmmHg) in CPB during cardiac operation is associated with an increased risk of AKI in cardiovascular surgery patients. Clinical attention should be paid to the potential role of CVP in predicting the occurrence of AKI.

Implementing an evidence-based guideline to decrease opioids after cardiac surgery.

Deaths related to overdoses continue growing in the United States. The overprescription of opioids after surgical procedures may contribute to this problem. There is inconsistency in the prescription of opioids in cardiovascular surgery patients. Recommendations regarding the reduction of opioids at discharge are not fully implemented. This is a single-center, pre-post quality improvement project in adult patients after elective cardiac surgery through sternotomy. Changes in guidelines, modification of order sets, creation of dashboards, and education to the providers to increase the prescription of acetaminophen around the clock on the step-down unit and at discharge, decrease the number of opioid tablets to 25 or less at discharge and decrease the prescription of opioids to 25 or less morphine milligram equivalents (MME) at discharge. The preintervention group included 67 consecutive patients who underwent cardiac surgery from November to December 2021. The postintervention group had 67 patients during the same period in 2022. Acetaminophen prescription on the step-down unit increased from 9% to 96% ( p < .001). The proportion of patients discharged with 25 or less opioid tablets increased from 18% to 90% ( p < .001) and with 25 or less MME from 30% to 55% ( p < .01). Acetaminophen prescription at discharge increased from 10% to 48% ( p < .001). Our intervention increased the use of acetaminophen and decreased the overprescription of opioids in cardiac surgery patients at discharge. Further research is necessary to continue improving pain management to reduce the number of opioids prescribed at discharge.

Evaluation of Analgesic Drug Therapy for Postoperative Pain Management in Cardiovascular Surgery

BackgroundCardiovascular surgery is usually associated with higher degree of postoperative pain, affecting the patient's physical recovery. Multiple clinical measures have been taken to avoid overuse of opioid for postoperative pain management, which led to the development of clinical pathways for analgesic drug treatment using a multimodal approach. ObjectiveTo evaluate the effectiveness and safety of a multimodal postoperative analgesic drug pathway (ADP) for the pain management following cardiovascular surgery. MethodsThis retrospective, controlled, non-randomized study evaluated postoperative ADP in patients undergoing cardiovascular surgery in a tertiary general hospital in Qingdao, China. Effectiveness and safety outcomes were compared before and after the implementation of ADP. Outcome indicators include postoperative pain scores, consumption of opioids in analgesic pumps and incidence of adverse events. ResultsPatients who underwent cardiovascular surgery from September to November 2021 before the implementation of ADP (N = 193) and from September to November 2022 after the implementation of ADP (N = 218) were enrolled. Pain scores were reduced on day 1, 3 and 5 after surgery and in mild pain, the reduction was most significant (P < 0.001). Opioid in analgesic pumps consumption was also significantly reduced and decreased incidence of adverse events such as nausea and vomiting (P = 0.026), respiratory inhibition (P = 0.027), and dizziness and headache (P = 0.028) were noted in cardiovascular surgery patients after ADP implementation. ConclusionsImproved effectiveness and safety were observed following the implementation of ADP. Multimodal analgesic ADP methodology can be effectively used for the postoperative pain management of cardiovascular surgery patients.

Evaluation of Machine Learning Approaches for Predicting Warfarin Discharge Dose in Cardiac Surgery Patients: Retrospective Algorithm Development and Validation Study.

Warfarin dosing in cardiac surgery patients is complicated by a heightened sensitivity to the drug, predisposing patients to adverse events. Predictive algorithms are therefore needed to guide warfarin dosing in cardiac surgery patients. This study aimed to develop and validate an algorithm for predicting the warfarin dose needed to attain a therapeutic international normalized ratio (INR) at the time of discharge in cardiac surgery patients. We abstracted variables influencing warfarin dosage from the records of 1031 encounters initiating warfarin between April 1, 2011, and November 29, 2019, at St Michael's Hospital in Toronto, Ontario, Canada. We compared the performance of penalized linear regression, k-nearest neighbors, random forest regression, gradient boosting, multivariate adaptive regression splines, and an ensemble model combining the predictions of the 5 regression models. We developed and validated separate models for predicting the warfarin dose required for achieving a discharge INR of 2.0-3.0 in patients undergoing all forms of cardiac surgery except mechanical mitral valve replacement and a discharge INR of 2.5-3.5 in patients receiving a mechanical mitral valve replacement. For the former, we selected 80% of encounters (n=780) who had initiated warfarin during their hospital admission and had achieved a target INR of 2.0-3.0 at the time of discharge as the training cohort. Following 10-fold cross-validation, model accuracy was evaluated in a test cohort comprised solely of cardiac surgery patients. For patients requiring a target INR of 2.5-3.5 (n=165), we used leave-p-out cross-validation (p=3 observations) to estimate model performance. For each approach, we determined the mean absolute error (MAE) and the proportion of predictions within 20% of the true warfarin dose. We retrospectively evaluated the best-performing algorithm in clinical practice by comparing the proportion of cardiovascular surgery patients discharged with a therapeutic INR before (April 2011 and July 2019) and following (September 2021 and May 2, 2022) its implementation in routine care. Random forest regression was the best-performing model for patients with a target INR of 2.0-3.0, an MAE of 1.13 mg, and 39.5% of predictions of falling within 20% of the actual therapeutic discharge dose. For patients with a target INR of 2.5-3.5, the ensemble model performed best, with an MAE of 1.11 mg and 43.6% of predictions being within 20% of the actual therapeutic discharge dose. The proportion of cardiovascular surgery patients discharged with a therapeutic INR before and following implementation of these algorithms in clinical practice was 47.5% (305/641) and 61.1% (11/18), respectively. Machine learning algorithms based on routinely available clinical data can help guide initial warfarin dosing in cardiac surgery patients and optimize the postsurgical anticoagulation of these patients.

Uso del catéter de arteria pulmonar en las primeras horas posoperatorias de cirugía cardiovascular de alto riesgo

IntroductionInformation on physiological phenomena in the postoperative period of cardiac surgery, pulmonary artery catheter (PAC) use, and medical behaviors derived from its measurement, is limited. ObjectiveTo describe the patterns of PAC use and therapeutic behaviors derived from it in the first postoperative hours of high-risk cardiovascular surgery. Materials and methodsRetrospective cohort study of high-risk cardiovascular surgery patients, managed with PAC in the intensive care unit of the Hospital Universitario San Ignacio in Bogotá D.C. (Colombia). The therapeutic interventions derived from the hemodynamic evaluation with this catheter were evaluated, taking into account the patterns of use and therapeutic behaviors according to the postoperative moment. ResultsForty-two patients were included. Median age 65 years, 59.5% men, 57.1% with EuroSCORE≥6. Median time of PAC use was 63 h (RIC 45–80). The number of PAC measurements per 12 h decreased from 2.16±0.53 in the first 12 h to 1.30±0.82 after 48 h (p: 0.0003). The number of behaviors taken from each measurement decreased from 1.48±0.45 to 0.71±0.51 (p: 0.0001) in the same period. There was significant reduction in number of behaviors associated with fluid, vasoactive, and vasodilator administration over time. ConclusionsOur data suggest that with the passage of hours the number of PAC measurements is decreasing, as well as the number of behaviors taken based on these measurements. These data suggest that many of the patients who maintained the pulmonary artery catheter for up to 48–72 h no longer required it. Further studies will be needed to clarify which patients benefit from pulmonary artery catheterization beyond 48 h.

Abstract 11649: Serum Adiponectin Levels Correlate With Atrial PPARγ and TGFβ1 mRNA Expression in Patients Receiving Cardiac Surgery: Involvement of PPARγ on Atrial Fibrotic Remodeling

Introduction: The peroxisome proliferator-activated receptor gamma (PPAR γ) plays important roles in regulating processes related to fibrogenesis. On the other hand, adiponectin, a marker for PPARγ activity, is a hormone involved in maintaining energy homeostasis, and exerts anti-profibrotic effects in various organs. However, the roles of PPARγ and adiponectin on atrial fibrotic remodeling are still unknown. Hypothesis: We investigated the association of serum adiponectin levels and atrial gene expression of adiponectin, PPARγ and fibrosis-related genes in cardiovascular surgery patients including heart valve disease. Methods: Atrial mRNA expression levels including adiponectin and PPARγ were analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) in 59 cases (sinus rhythm (SR) 24 patients, atrial fibrillation (AF) 35 patients) in which left atrium (LA) tissues were removed from the appendage during surgery. The immunohistochemical studies were used to identify the protein expression. The serum levels of adiponectin were measured by ELISA. Results: The immunohistochemical staining showed the expression of adiponectin, PPARγ and PPARα. The significant correlations were observed among the mRNA expression levels of extracellular matrix (ECM) (COL1A1, COL3A1, fibronectin) and the fibrosis-related genes such as TGFβ1, TIMP1, MMP2, NOX2, CTGF and PDGFD attributed to the fibrosis of myocardium. The mRNA expression level of PPARγ, but not PPARα, positively correlated with that of the ECM and the fibrosis-related gene expression level. The mRNA expression level of adiponectin also positively correlated with that of ECM. Patients with AF had higher atrial expression level of adiponectin, PPARγ, COL1A1 and TGFβ than those with SR. Serum adiponectin levels significantly correlated with atrial mRNA expression level of PPARγ and TGFβ1. Patients with AF had serum higher levels of adiponectin than those with SR. Conclusions: Atrial PPARγ and adiponectin associate with atrial fibrotic remodeling in cardiovascular surgery patients. Serum adiponectin levels correlate with atrial PPARγ and TGFβ1 mRNA expression, and might have potential utility as a biomarker in atrial fibrotic remodeling.

Surgical scheduling via optimization and machine learning with long-tailed data : Health care management science, in press.

Using data from cardiovascular surgery patients with long and highly variable post-surgical lengths of stay (LOS), we develop a modeling framework to reduce recovery unit congestion. We estimate the LOS and its probability distribution using machine learning models, schedule procedures on a rolling basis using a variety of optimization models, and estimate performance with simulation. The machine learning models achieved only modest LOS prediction accuracy, despite access to a very rich set of patient characteristics. Compared to the current paper-based system used in the hospital, most optimization models failed to reduce congestion without increasing wait times for surgery. A conservative stochastic optimization with sufficient sampling to capture the long tail of the LOS distribution outperformed the current manual process and other stochastic and robust optimization approaches. These results highlight the perils of using oversimplified distributional models of LOS for scheduling procedures and the importance of using optimization methods well-suited to dealing with long-tailed behavior.

Cardiac surgery of aortic valve and ascending aorta (Bentall procedure) in a patient with Fabry disease without enzyme replacement therapy: an overview of aortic and aortic valve surgical tips

Introduction: Fabry disease (FD) is a rare disease in which cardiovascular events are one of its manifestations. Aortic and mitral valve involvement are among its manifestations, but due to the concern of suture failure without enzyme replacement therapy (ERT), the desire for its surgery has been very low, and its reported cases have been few. After the introduction of ERT, cardiovascular surgery for such patients has been gradually reported from different places, but due to the high cost of ERT, it is not practically available to patients in the third world and the backward countries. Reports of the experiences of patients with FD who underwent cardiac surgery without ERT can help improve cardiac surgery in these patients. Case Report: A 34-year-old man diagnosed with FD due to chronic renal failure and underwent dialysis 3 times a week for 1.5 years became a candidate for kidney transplant. In pre-transplant examinations, dilatation of aortic root and aortic valve insufficiency were diagnosed, and the patient’s kidney transplant surgery was postponed until after cardiac surgery. The patient underwent cardiac surgery, aortic valve replacement, and ascending aortic replacement, as well as re-implantation of both right and left coronary buttons on the ascending aorta (Bentall procedure). The post-surgery period passed without any special event. The patient’s dialysis continued; after 4 months, he underwent kidney transplant surgery, and the one-year follow-up period also was good. Conclusion: Although there is very little evidence of cardiovascular surgery in patients with FD without ERT, and surgeons have always been worried about suture failure and complications of cardiac surgery, due to the high cost of ERT, this treatment is not available to everyone. The introduced patient underwent cardiac surgery by Bentall procedure without receiving ERT and was discharged without any special complications. By reporting and collecting similar cases, guidance may be provided for patients with FD for whom ERT is not available.

PO-01-020 PERI-OPERATIVE AMIODARONE PROPHYLAXIS IN CARDIOVASCULAR SURGERY: IMPACTS ON POST-OPERATIVE LENGTH OF STAY ACCORDING TO PROCEDURE TYPES

Post-operative Atrial Fibrillation (POAF), occurring in nearly 20-50 percent of cardiovascular surgery (CVS) patients, is associated with prolonged hospitalization and excess costs of care. Peri-operative Amiodarone prophylaxis has been an effective strategy to reduce the incidence of POAF. A retrospective evaluation of the impact of Amiodarone prophylaxis on post-operative length of hospital (LOS) stay, according to CVS procedure types. Hospitalization information was available for 2704 consecutive CVS patients at a single tertiary care centre (2013-2016). CVS included standalone, or combined procedures that involved: valvular heart surgery (VHS), coronary artery bypass graft (CABG), and other miscellaneous procedures (e.g. ascending aorta replacement, endarterectomy). Hierarchical linear regression was used to evaluate the impact of Amiodarone prophylaxis on LOS, adjusted for demographic and clinical characteristics. Among the 2704 patients, there were 866 (32.0%) cases of POAF. LOS, was significantly longer in patients with POAF (+2.78 days, p<0.001). LOS was 1.62 days shorter in patients who received Amiodarone prophylaxis (p=0.007). Within all operative categories, LOS was shorter in patients receiving amiodarone prophylaxis, though statistical significance was only observed in VHS (including VHS + other) and VHS + CABG procedure types. Specifically, Amiodarone prophylaxis was associated with shorter LOS among: patients who had CABG but not VHS (8.26 versus 9.45 days, p= 0.29), patients who had VHS but not CABG (7.62 versus 11.02 days, p<0.001), patients undergoing VHS + CABG (9.36 vs. 12.41 days, p<0.03), and patients undergoing VHS + CABG + other (13.54 versus 15.09 days, p= 0.74). After adjusting for demographic-clinical covariates in a hierarchical multiple regression, Amiodarone prophylaxis remained an independent predictor of shorter LOS (b= -2.3 [-3.7, -0.93], p= 0.001). Other independent predictors included: left atrial diameter of >40 mm (b= 1.7 [0.90, 2.85], p< 0.001), female sex (b= 1.4 [0.56, 2.19], p= 0.001), history of heart failure (b= 2.1 [0.94, 3.30], p< 0.001), and CVS involving VHS + CABG (b= 1.4 [0.15, 2.67], p= 0.03), and VHS + CABG + other (b= 5.1 [2.51, 7.72], p<0.001). Amiodarone prophylaxis is independently associated with significantly shorter LOS following CVS.

PO-01-019 PRE-OPERATIVE DISCONTINUATION OF NOVEL ORAL ANTICOAGULANTS IN CARDIOVASCULAR SURGERY: HOLD TIME IS ASSOCIATED WITH LENGTH OF STAY

Pre-operative discontinuation of novel oral anticoagulants (NOACs) in cardiovascular surgery (CVS) is necessary to reduce peri-operative bleeding risks. However, there is little data on optimal pre-operative hold times for these agents and their effect on the length of stay (LOS). A retrospective evaluation of the effect of pre-operative NOAC hold times (i.e. ≤2 or ≥3 days) with or without heparin bridging, on LOS (i.e. hospital and ICU). Baseline and follow-up clinical data were collected for consecutive CVS patients treated with NOACs at a single tertiary care centre (2013-2016). After calculations of bivariate associations and between-group differences, multivariate linear regression was used to evaluate the association between NOAC hold times and post-operative complications and LOS. In 107 patients (age= 73.6±7.7 years, 72.9% male, 83.2% Atrial Fibrillation history), NOACs hold times ranged from: ≤2 days (Group 1, n= 17), ≥ 3 days without heparin (Group 2, n= 63), and ≥3 days with heparin (Group 3, n= 27). Mean LOS were respectively 20.0 (25.8), 7.6 (4.12), and 13.6 (8.21) days post-operation (Group 1- Group 2= 12.4 days; p= 0.001). In contrast, length of ICU stays did not differ between groups (3.6, 1.9, 3.1 days in groups 1-3 respectively, p= 0.17). Aside from significantly higher LOS among patients with major bleeding (15.3 vs. 8.2 days, p= 0.01) or a bleeding episode (18.1 vs. 8.3 days, p= 0.01), there were no significant differences in LOS according to baseline comorbidities or other CVS complications. Multivariate linear regression model, adjusted for age, sex, NOACs and procedure type (elective versus emergent), indicated significantly shorter LOS when NOACs were held ≥3 days without heparin (Group 2) compared to ≤2 days pre-op (Group 2: b= -11.70 [-17.94, -5.46], p< 0.001, Adj. R2= 0.19). Despite trending towards lower LOS, group 3 (i.e. ≥3 days with heparin) was not associated with significantly lower LOS (Group 3: b= -5.24 [-12.09, 1.61], p= 0.13). These findings persisted even after additional adjustment for major bleeding (Group 2: b= -10.46 [-16.62, -4.31], p= 0.001, Adj. R2= 0.23) or postoperative bleeding episode (Group 2: b= -9.30 [-15.45, -3.15], p= 0.003, Adj. R2= 0.26). Compared to NOACs held ≤2 days before CVS, holding NOACs for ≥3 days before CVS without heparin bridging was independently associated with shorter LOS, even after adjustment for differences in major bleeding.

PO-01-018 PRE-OPERATIVE DISCONTINUATION OF NOVEL ORAL ANTICOAGULANTS IN CARDIOVASCULAR SURGERY: IS TWO DAYS ENOUGH?

Discontinuation of novel oral anticoagulants (NOACs) to minimize peri-operative bleeding risk is integral before invasive cardiovascular surgery (CVS). There is little data on the optimal number of days NOACs should be held pre-operatively in these patients. A retrospective evaluation of major bleeding, and its association with the number of days NOACs were held pre-operatively, and whether or not heparin bridging was used. Major bleeding was defined according to the International Society on Thrombosis and Haemostasis (ISTH). Major bleeding is defined as: either a hemoglobin drop of >20 g/L, 2U blood transfusion, symptomatic/ critical organ bleeding, or fatal bleeding. Baseline and follow-up clinical information were collected for consecutive CVS patients treated with NOACs between 2013-2016 at a single tertiary care centre. Multivariate logistic regression models were employed to evaluate major bleeding and post-operative bleeding risks associated with different NOACs hold periods. In 107 (72.9% male) patients (age= 73.6±7.7 years), 89 (83.2%) of whom had a history of Atrial Fibrillation (AF), NOACs were stopped on average 4.5±2.4 days pre-operation, including: 17 (Group 1) within ≤2 days, 63 (Group 2) ≥3 days without heparin, and 27 (Group 3) ≥3 days with heparin bridging. There were no statistically significant differences in baseline comorbidities between the three Groups. Major bleeding rates ranged from 58.8, 30.6, 55.6% (p= 0.03), and bleeding episode rates ranged between 52.9, 16.1, 44.4% (p= 0.002) in Groups 1, 2, and 3 respectively. Multivariate logistic regression adjusted for age, sex, NOAC type, and procedure type (elective vs. emergent), showed that stopping NOAC ≥3 days (vs. ≤2 days) before surgery without heparin bridging (i.e. Group 2) was independently associated with a significantly lower risks of major bleeding (OR: 0.29 [0.08, 1.00], p= 0.05) and bleeding episode (OR: 0.16 [0.04, 0.61], p= 0.007). Compared to ≤2 days hold, NOAC hold of ≥3 days with heparin was not associated with lower risks of major bleeding (OR: 0.96 [0.25, 3.65], p= 0.95) and bleeding episode (OR: 0.77 [0.21, 2.91], p= 0.70). NOAC discontinuation ≥3 days without heparin bridging before CVS was associated with significantly lower risk of major bleeding and post-operative bleeding episode compared to the ≤2 days stop period.

Incorporation of pharmacist pre-surgical calls to improve medication history completion rates.

The accuracy and timeliness of documenting a medication history is an important aspect to ensure appropriate medication reconciliation during transitions of care. Surgical patients often have their medication history recorded just moments before surgery which may be rushed, incomplete or missed entirely. Between January and May 2020, 76.7% of surgical patients admitted to our institution had a medication history completed by a pharmacist prior to surgery. The objective of this work is to improve the pharmacist medication history completion rates for pre-surgical patients before surgery by integrating pharmacist-led medication histories into the pre-operative pathway. Through interdisciplinary collaboration, the pre-operative pathway for surgical patients was evaluated for opportunities to complete medication histories days prior to their scheduled procedure. Plan-Do-Study-Act (PDSA) cycles were utilized to make incremental improvements in practice. Through an iterative process, the pathway for cardiovascular surgery (CVS) patients was modified to include a scheduled pharmacist phone appointment in the days leading up to their surgical procedure. Utilizing these phone appointments, pharmacists complete patient medication history reviews and share a feedback loop to cardiovascular and peri-operative health care providers. The iterative PDSA cycles revealed challenges to completing pre-surgical medication history calls without advance notice. Patient responsiveness to pre-surgical medication history calls improved with the incorporation of scheduled phone appointments. Between January 18 and May 31, 2021, pharmacists completed 359 of 376 scheduled CVS appointments (95.5%), improving the medication history completion rates for cardiovascular surgery patients from 84.8 to 93.0% (p = 0.000025). The completion rate for all surgical patients also improved from 76.7 to 85.1% (p<0.00001). Incorporating scheduled pharmacist medication history appointments as a part of the pre-operative pathway was shown to expand the capacity for pharmacists to complete medication histories for patients prior to surgery. By reducing pharmacist workload on the morning of surgery, fewer patients were admitted to surgery without having their medication history reviewed by pharmacy. Future investigation should be considered to evaluate the impact on patient outcomes.

A patient blood management perspective on Anemia in the obese patient journey

Obesity and anemia are increasing prevalence around the globe. They can interplay and are both associated with high morbidity and poorer clinical outcomes. Inflammation and iron deficiency are important contributors to anemia in obese patients. Furthermore, obesity surgery can trigger high blood loss, increased demand for blood transfusions and long-term nutrient deficiency. Patient blood management programs have been crucial in improving patients' clinical results whilst minimizing costs in many different settings, such as orthopedic surgery, cardiovascular surgery, pregnancy and intensive care unit patients. In this mini-review, we will discuss applications of patient blood management principles in caring of obese individuals during the patient journey.

Effect of menthol lozenges after extubation on thirst, nausea, physiological parameters, and comfort in cardiovascular surgery patients: A randomized controlled trial

ObjectivesTo determine the effect of post-extubation oral menthol lozenges on thirst, nausea, physiological parameters, and comfort level in patients undergoing cardiovascular surgery. Research methodology/designThe study was a single-centre, randomized controlled trial. SettingThis study included 119 patients undergoing coronary artery bypass graft surgery in a training and research hospital. Patients in the intervention group (n = 59) received menthol lozenges at 30, 60, and 90 min after extubation. Patients in the control group (n = 60) received standard care and treatment. Main outcome measuresThe primary outcome of the study was the change in post-extubation thirst assessed by Visual Analogue Scale after using menthol lozenges compared to baseline. Secondary outcomes were changes in post-extubation physiological parameters and nausea severity assessed by Visual Analogue Scale compared to baseline, and comfort level assessed with Shortened General Comfort Questionnaire. ResultsBetween-group comparisons showed that the intervention group had significantly lower thirst scores at all time points and nausea at the first assessment (p < 0.05) and significantly higher comfort scores (p < 0.05) than the control group. There were no significant differences between the groups in physiological parameters at baseline or any of the postoperative assessments (p > 0.05). ConclusionIn patients undergoing coronary artery bypass graft surgery, the use of menthol lozenges effectively increased comfort level by reducing post-extubation thirst and nausea, but had no effect on physiological parameters. Implications for clinical practiceNurses should be vigilant for complaints such as thirst, nausea, and discomfort in patients after extubation. Nurses’ administration of menthol lozenges to patients may help reduce post-extubation thirst, nausea, and discomfort.

1139: FOUR-FACTOR PROTHROMBIN COMPLEX CONCENTRATE FOR REFRACTORY BLEEDING IN TRAUMA AND CARDIAC SURGERY

Introduction: Four-Factor Prothrombin Complex Concentrate (4F-PCC) is a concentrated product containing factors II, VII, IX, X, proteins C and S, that is FDA approved for reversal of vitamin K antagonists in adults with acute major bleeding or need for urgent surgery. The utilization of factor products for off-label indications has been increasing secondary to continued national blood shortages and ease of administration, with the hope of reducing blood product utilization. Methods: This single-center retrospective study at an academic level I trauma center analyzed the use of 4F-PCC for refractory bleeding between June 2018 and March 2022 in adult trauma and cardiovascular surgery patients. The primary objective was to determine blood product utilization in patients during a time period of six hours pre and post 4F-PCC administration. Secondary outcomes included thrombotic events, mortality, and use of supportive hemostatic medications. Results: Thirty-five patients received 4F-PCC for significant exsanguination refractory to massive transfusion: cardiac (n=32, 91%) and trauma surgery (n=3, 9%). The median age was 62 years (IQR 50-69) and the majority were male (n=21, 60%). The median dose administered was 2128 units (IQR 1668-2750) or 25 units/kg of factor IX (IQR 20.7-29). Units of blood products given pre and post 4F-PCC administration were: packed red blood cells (PRBC) [5.4 (IQR 3.2-8.9), 2.1 (IQR 1.8-4.1) p< 0.01], fresh frozen plasma (FFP) [4.4 (IQR 2.5-8.0), 3.4 (IQR 1.3-4.7) p=0.03], platelets [1.9 (IQR 1.1-2.2), 1.2 (IQR 1.0-2.2) p=0.20] and cryoprecipitate [1.3 (IQR 0.8-2.4), 0.9 (IQR 0.8-1.8) p=0.83]. Five patients experienced thrombotic events and the mortality was 29%. Three patients received concomitant phytonadione and seven received desmopressin. Conclusions: There was a significant reduction in PRBC and FFP units transfused after 4F-PCC administration in patients for refractory bleeding for trauma and cardiac surgery patients. Further investigation is warranted to determine if the reduction in product administration results in differences in clinical outcomes and if this finding is replicated in other surgical populations.

791: IMPACT OF SEDATION WITH KETAMINE COMPARED TO BENZODIAZEPINES ON DELIRIUM IN THE INTENSIVE CARE UNIT

Introduction: The use of high-dose ketamine infusions for sedation has grown in popularity as an alternative to benzodiazepines in intensive care unit (ICU) patients. Currently, there is a paucity of literature describing the use of high-dose ketamine for sedation. The objectives of this study are to describe high-dose ketamine use in the ICU and its impacts on delirium compared to benzodiazepines. Methods: This is a single-center, retrospective cohort study of patients admitted to an ICU between 5/5/2018 and 12/1/2021. Neurocritical care and cardiovascular surgery patients were excluded. Patients included were mechanically ventilated for ≥ 48 hours and received either ketamine ≥ 1 mg/kg/hr or a benzodiazepine infusion (midazolam or lorazepam) for ≥ 24 hours during their index ICU stay. and baseline demographics, sedative drip information, CAM-ICU scores, hospital and ICU length of stay (LOS), duration of mechanical ventilation, and chloride disturbances were collected The primary outcome was the percentage of eligible ICU days CAM-ICU positive, and secondary outcomes included ICU LOS and duration of mechanical ventilation. Eligible ICU days were defined as days with a Richmond Agitation Sedation Scale score ≥ - 3, and a CAM-ICU positive day was defined as having one positive CAM-ICU score positive. Results: A total of 187 patients were included, with 70 and 117 patients in the ketamine and benzodiazepine groups, respectively. The mean age was 56.9 (14.7), and 64.2% were male. The percentage CAM-ICU positive days in the ICU was 68.1% for ketamine and 51.5% for benzodiazepines (p=0.15). The median ICU LOS in days was 20.1 (11.6, 38.9) for the ketamine arm compared to 15.9 (8.7, 26.0) for the benzodiazepine arm (p=0.069). The median duration of mechanical ventilation in days was 19.5 (7.4, 37.4) compared to 11 (6.1, 22.0) for ketamine and benzodiazepines respectively (p=0.053). Overall, 57.5% of ketamine arm patients and 44.1% of benzodiazepine arm patients died during hospitalization (p=0.17). Conclusions: Compared to benzodiazepine infusions, high-dose ketamine infusions did not result in a significantly different number of CAM-ICU positive ICU days, ICU LOS, or duration of mechanical ventilation.

Prevalence and factors associated with pressure injury in patients undergoing open heart surgery: A systematic review and meta-analysis.

Pressure injuries (PIs) are one of the major and costliest medical problems with severe implications for patients. Cardiovascular surgery patients are at the higher risk of developing surgery-related PIs. So this study was conducted with the aim of investigating the prevalence and factors associated with PIs in patients undergoing open heart surgery. We identified articles through electronic databases such as Web of Science, Scopus, PubMed, ProQuest; and Persian Databases: SID, Magiran and Irandoc without restriction on language or publication period (from inception through June 2022). Finally, 17 studies that fulfilled eligibility criteria were included in final systematic review and meta-analysis. Data analyses were conducted using STATA version 14. The pooled prevalence of PI in patients undergoing open heart surgery was 24.06% (95% CI: 17.85-30.27). High heterogeneity was observed across the included studies (I2 = 96.0, P< 0.000). The prevalence by gender was reported as 25.19% (95% CI: 13.45-36.93) in men and 33.36% (95 CI%: 19.99-46.74) in women. The result showed there was statistically significant association between PI and Female sex (Pooled Est: 1.551, 95% CI: 1.199-2.006, z= 3.345, P= 0.001), diabetes (Pooled Est: 1.985, 95% CI: 1.383-2.849, z= 3.719, P= 0.000), advanced age (SMD: 0.33 years; 95% CI: 0.09-0.57), Duration of surgery (SMD: 0.47; 95% CI: 0.19-0.75) and preoperative serum albumin level (SMD: 0.56; 95% CI: 0.14-0.98). The relatively high PIs incidence among patients undergoing open heart surgery suggests that typical PI prevention methods are insufficient for this population. Targeted prevention measures must be developed and implemented.

The Relationship between the Incidence of Postoperative Cognitive Dysfunction and Intraoperative Regional Cerebral Oxygen Saturation after Cardiovascular Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: To assess whether intraoperative monitoring and intervention of regional cerebral oxygen saturation levels can reduce the incidence of postoperative cognitive dysfunction in patients undergoing cardiovascular surgery and contribute to patient prognosis. Methods: The Cochrane Library, PubMed, and the Web of Science were systematically searched for relevant randomized controlled trials involving the effects of cerebral oxygen saturation on the cognitive function of patients after cardiovascular surgery from January 1, 2000 to May 1, 2022. The primary outcome was the incidence of postoperative cognitive dysfunction. The secondary outcomes were length of hospital stay, length of intensive care unit (ICU) stay, length of mechanical ventilation, length of cardiopulmonary bypass, and other major postoperative outcomes such as renal failure, infection, arrhythmia, hospital mortality, and stroke. Data were pooled using the risk ratio or standardized mean difference with 95% confidence interval (CI). The original study protocol was registered prospectively with PROSPERO (CRD42020178068). Results: A total of 13 randomized controlled trials involving 1669 cardiovascular surgery patients were included. Compared with the control group, the risk of postoperative cognitive dysfunction was significantly lower in the intervention group (RR = 0.50; 95% CI: 0.30 to 0.85; p = 0.01; I2 = 71%). The Duration of stay in intensive care units in the intervention group was also significantly shorter than that in the control group (standard mean difference (SMD) = –0.14; 95% CI: –0.26 to –0.01; p = 0.03; I2 = 26%). Univariate meta-regression analyses showed that age is a major source of heterogeneity. Conclusions: Our current study suggests that intraoperative cerebral oxygen saturation monitoring and intervention can significantly reduce the incidence of postoperative cognitive dysfunction, and the length of intensive care unit stay after intervention is considerably reduced. Given that some limits in this review, more high-quality, and long-term trials are still needed to certify our findings.

Abstract 9449: Increased Neprilysin Expression Links Atrial Fibrotic Remodeling in Cardiovascular Surgery Patients

Introduction: Deposition of extracellular matrix (ECM) such as collagen leads to fibrosis, which plays essential roles in structural remodeling in atrial fibrillation (AF). Neprilysin (NEP) is an integral membrane-bound metallopeptidase with a wide spectrum of substrates and physiological functions. Hypothesis: We investigated the association of NEP and the atrial fibrosis-related genes in cardiovascular surgery patients including heart valve disease. Methods: Atrial mRNA expression including collagen and NEP were analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) in 59 cases (sinus rhythm (SR) 24 patients, AF 35 patients) in which LA tissues were removed from the appendage during surgery. NEP mRNA expression was also analyzed in adipose tissues (AT) obtained from both epicardial and subcutaneous adipose tissues. The NEP protein expression was measured by western blotting analysis and immunohistochemistry staining, and serum level of NEP was measured by ELISA. Results: The immunohistochemical staining showed the expression of NEP in both AT and LA. Higher expression of NEP mRNA and protein in adipose tissues was observed, compared with LA. Serum NEP concentration did not significantly correlate with NEP mRNA and protein expression of AT and LA. The significant correlations were observed among ECM (COL1A1, COL3A1, fibronectin) and the five selected fibrosis-related genes (TGFβ1, CTGF, miR21, NOX2 and BAX) attributed to the fibrosis of myocardium in LA. NEP mRNA expression of LA also positively correlated with the ECM and the fibrosis-related gene expression level. The multiple regression analysis revealed TGFβ1, NOX2, and NEP as independent predictors of atrial COL1A1 mRNA expression level. In addition, it revealed NEP as an independent predictor of COL1A1 mRNA expression level, even adjusted by age, sex, and BMI. Serum NEP concentration did not correlate with the ECM and the fibrosis-gene expression level. Patients with AF had higher atrial expression of NEP protein, compared to those with SR. Conclusions: Increased atrial expression of NEP links atrial fibrotic remodeling and developing AF in cardiovascular surgery patients. However, serum NEP did not reflect atrial NEP expression in LA.

Association between remimazolam and postoperative delirium in older adults undergoing elective cardiovascular surgery: a prospective cohort study.

Postoperative delirium is one of the most common complications after cardiovascular surgery in older adults. Benzodiazepines are a reported risk factor for delirium; however, there are no studies investigating remimazolam, a novel anesthetic agent. Therefore, we prospectively investigated the effect of remimazolam on postoperative delirium. We included elective cardiovascular surgery patients aged ≥ 65years at Hamamatsu University Hospital between August 2020 and February 2022. Patients who received general anesthesia with remimazolam were compared with those who received other anesthetics (control group). The primary outcome was delirium within 5days after surgery. Secondary outcomes were delirium during intensive care unit stay and hospitalization, total duration of delirium, subsyndromal delirium, and differences in the Mini-Mental State Examination scores from preoperative to postoperative days 2 and 5. To adjust for differences in the groups' baseline covariates, we used stabilized inverse probability weighting as the primary analysis and propensity score matching as the sensitivity analysis. We enrolled 200 patients; 78 in the remimazolam group and 122 in the control group. After stabilized inverse probability weighting, 30.3% of the remimazolam group patients and 26.6% of the control group patients developed delirium within 5days (risk difference, 3.8%; 95% confidence interval -11.5% to 19.1%; p = 0.63). The secondary outcomes did not differ significantly between the groups, and the sensitivity analysis results were similar to those for the primary analysis. Remimazolam was not significantly associated with postoperative delirium when compared with other anesthetic agents.