ABSTRACT Objective: To define a reference chart comparing pressure drop vs. flow generated by a set of arterial cannulae currently utilized in cardiopulmonary bypass conditions in pediatric surgery. Methods: Cannulae from two manufacturers were selected considering their design and outer and inner diameters. Cannula performance was evaluated in terms of pressure drop vs. flow during simulated cardiopulmonary bypass conditions. The experimental circuits consisted of a Jostra HL-20 roller pump, a Quadrox-i pediatric oxygenator (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set. The circuit was primed with lactated Ringer’s solution only (first condition) and with human packed red blood cells added (second condition) to achieve a hematocrit of 30%. Cannula sizes 8 to 16 Fr were inserted into the cardiopulmonary bypass circuit with a “Y” connector. The flow was adjusted in 100 ml/min increments within typical flow ranges for each cannula. Pre-cannula and post-cannula pressures were measured to calculate the pressure drop. Results: Utilizing a pressure drop limit of 100 mmHg, our results suggest a recommended flow limit of 500, 900, 1400, 2600, and 3100 mL/min for Braile arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, respectively. For Medtronic DLP arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, the recommended flow limit is 600, 1100, 1700, 2700, and 3300 mL/min, respectively. Conclusion: This study reinforces discrepancies in pressure drop between cannulae of the same diameter supplied by different manufacturers and the importance of independent translational research to evaluate components’ performance. Objective vs surgery Methods diameters HL20 HL 20 HL-2 pump Quadroxi Quadrox i Maquet AG Rastatt Germany, Germany , Germany) Ringers Ringer s first condition second 30 30% 1 Y “Y connector 10 mlmin ml min cannula Precannula Pre postcannula post Results mmHg 500 900 1400 2600 310 mLmin mL 12 14 respectively 600 1100 1700 2700 330 Conclusion components HL2 2 HL- 3 50 90 140 260 31 60 110 170 270 33 5 9 26 6 11 17 27

ABSTRACT Introduction: The use of multiple arterial grafts (MAGs) has an impact on patient survival; however, preference for its use in the acute phase of myocardial infarction (AMI) has not yet been established. This study aimed to compare the short-mid-term clinical results of AMI patients undergoing coronary artery bypass grafting (CABG) with a single arterial graft (SAG) vs. MAGs. Methods: This is a cross-sectional cohort study of 4,053 patients from the Registro Paulista de Cirurgia Cardiovascular II (REPLICCAR II). CABG in the AMI was considered when performed between one and seven days after diagnosis (n=238). Thirty-five patients underwent surgery with ≥ 2 arterial grafts (MAG group), population adjustment in SAG group was performed using the propensity score matching (PSM). Clinical follow-up was performed by telephone to assess need for readmission, new AMI, reoperation, and death. Results: After PSM, 70 patients were evaluated. During hospitalization, a significant statistical difference was observed in the surgery duration: the MAG group had a median of 4.78 hours while the SAG group had 4.11 hours (P=0.040). Within the MAG group, there was a predominance use of bilateral internal thoracic artery (62.86%), followed by radial graft associated with the use of left internal thoracic artery (28.57%) and the combination of the three grafts (8.57%). There were no significant differences between the groups in terms of outcomes up to 30 days after CABG or up to five years after CABG. Conclusion: In REPLICCAR II, usage of MAGs in the AMI was not associated with clinical worsening of patients until the mid-term follow-up. Introduction (MAGs survival however (AMI established shortmidterm short mid term (CABG (SAG vs Methods crosssectional cross sectional 4053 4 053 4,05 II. . II) n=238. n238 n n=238 238 (n=238) Thirtyfive Thirty , group) PSM. PSM (PSM) followup follow readmission reoperation death Results 7 evaluated hospitalization duration 478 78 4.7 411 11 4.1 P=0.040. P0040 P P=0.040 0 040 (P=0.040) 62.86%, 6286 62.86% 62 86 (62.86%) 28.57% 2857 28 57 (28.57% 8.57%. 857 8.57% 8 (8.57%) 3 Conclusion midterm followup. up. 405 05 4,0 n23 n=23 23 (n=238 (PSM 47 4. 41 1 P004 P=0.04 04 (P=0.040 628 62.86 6 (62.86% 28.57 285 5 (28.57 85 8.57 (8.57% 40 4, n2 n=2 (n=23 P00 P=0.0 (P=0.04 62.8 (62.86 28.5 (28.5 8.5 (8.57 n= (n=2 P0 P=0. (P=0.0 62. (62.8 28. (28. 8. (8.5 (n= P=0 (P=0. (62. (28 (8. (n P= (P=0 (62 (2 (8 (P= (6 ( (P

ABSTRACT Objective: To investigate the association between body mass index (BMI), obesity, clinical outcomes, and mortality following coronary artery bypass grafting (CABG) in Brazil using a large sample with one year of follow-up from the Brazilian Registry of Cardiovascular Surgeries in Adults (or BYPASS) Registry database. Methods: A multicenter cohort-study enrolled 2,589 patients submitted to isolated CABG and divided them into normal weight (BMI 20.0-24.9 kg/m2), overweight (BMI 25.0-29.9 kg/m2), and obesity (BMI > 30.0 kg/m2) groups. Inpatient postoperative outcomes included the most frequently described complications and events. Collected post-discharge outcomes included rehospitalization and mortality rates within 30 days, six months, and one year of follow-up. Results: Sternal wound infections (SWI) rate was higher in obese compared to normal-weight patients (relative risk [RR]=5.89, 95% confidence interval [CI]=2.37-17.82; P=0.001). Rehospitalization rates in six months after discharge were higher in obesity and overweight groups than in normal weight group (χ2=6.03, P=0.049); obese patients presented a 2.2-fold increase in the risk for rehospitalization within six months compared to normal-weight patients (RR=2.16, 95% CI=1.17-4.09; P=0.045). Postoperative complications and mortality rates did not differ among groups during time periods. Conclusion: Obesity increased the risk for SWI, leading to higher rehospitalization rates and need for surgical interventions within six months following CABG. Age, female sex, and diabetes were associated with a higher risk of mortality. The obesity paradox remains controversial since BMI may not be sufficient to assess postoperative risk in light of more complex and dynamic evaluations of body composition and physical fitness. Objective BMI, , (BMI) (CABG followup follow up or BYPASS database Methods cohortstudy cohort study 2589 2 589 2,58 20.024.9 200249 20.0 24.9 20 0 24 9 20.0-24. kg/m2, kgm2 kgm kg/m2 kg m2 m 25.029.9 250299 25.0 29.9 25 29 25.0-29. 300 30. events postdischarge post 3 days followup. up. Results SWI (SWI normalweight relative RR=5.89, RR589 RR =5.89, 5 89 [RR]=5.89 95 CI=2.3717.82 CI2371782 CI =2.37 17.82 37 17 82 [CI]=2.37-17.82 P=0.001. P0001 P P=0.001 . 001 P=0.001) χ2=6.03, χ2603 χ χ2 6 03 (χ2=6.03 P=0.049 P0049 049 P=0.049) 2.2fold 22fold fold 2.2 RR=2.16, RR216 16 (RR=2.16 CI=1.174.09 CI117409 CI=1.17 4.09 1 4 09 CI=1.17-4.09 P=0.045. P0045 P=0.045 045 P=0.045) periods Conclusion Age sex fitness 258 58 2,5 024 20.024. 20024 200 20. 249 24. 20.0-24 kg/m 029 25.029. 25029 250 25. 299 29. 25.0-29 RR=5.89 RR58 =5.89 8 [RR]=5.8 3717 CI=2.3717.8 CI237178 237 =2.3 1782 17.8 [CI]=2.37-17.8 P000 P=0.00 00 χ2=6.03 χ260 (χ2=6.0 P=0.04 P004 04 2fold 22 2. RR=2.16 RR21 (RR=2.1 174 CI=1.174.0 CI11740 CI117 CI=1.1 409 4.0 CI=1.17-4.0 2, 02 20.024 2002 20.0-2 25.029 2502 25.0-2 RR=5.8 RR5 =5.8 [RR]=5. 371 CI=2.3717. CI23717 23 =2. 178 17. [CI]=2.37-17. P00 P=0.0 χ2=6.0 χ26 (χ2=6. RR=2.1 RR2 (RR=2. CI=1.174. CI1174 CI11 CI=1. 40 4. CI=1.17-4. 20.02 20.0- 25.02 25.0- RR=5. =5. [RR]=5 CI=2.3717 CI2371 =2 [CI]=2.37-17 P0 P=0. χ2=6. (χ2=6 RR=2. (RR=2 CI=1.174 CI1 CI=1 CI=1.17-4 RR=5 =5 [RR]= CI=2.371 CI237 = [CI]=2.37-1 P=0 χ2=6 (χ2= RR=2 (RR= CI= CI=1.17- RR= [RR] CI=2.37 CI23 [CI]=2.37- P= χ2= (χ2 (RR [RR CI=2.3 CI2 [CI]=2.37 (χ CI=2. [CI]=2.3 CI=2 [CI]=2. [CI]=2 [CI]= [CI] [CI

ABSTRACT Introduction: The aims of this study were to determine the incidence of severe and moderate primary graft dysfunction (PGD) in our center, to identify, retrospectively, donors’ and recipients’ risk factors for PGD development, and to evaluate the impact of PGD within 30 days after heart transplantation. Methods: Donors’ and recipients’ medical records of 64 consecutive adult cardiac transplantations performed between January 2016 and June 2017 were reviewed. The International Society for Heart and Lung Transplantation (ISHLT) criteria were used to diagnose moderate and severe PGD. Associations of risk factors for combined moderate/severe PGD were assessed with appropriate statistical analyses. Results: Sixty-four patients underwent heart transplantation in this period. Twelve recipients (18.7%) developed severe or moderate PGD. Development of PGD was associated with previous donor cardiopulmonary resuscitation and a history of prior heart surgery in the recipient (P=0.01 and P=0.02, respectively). The 30-day in hospital mortality was similar in both PGD and non-PGD patients. Conclusion: The use of the ISHLT criteria for PGD is important to identify potential risk factor. The development of PGD did not affect short-term survival in our study. More studies should be done to better understand the pathophysiology of PGD.

ABSTRACT Introduction: The aims of this study were to determine the incidence of severe and moderate primary graft dysfunction (PGD) in our center, to identify, retrospectively, donors’ and recipients’ risk factors for PGD development, and to evaluate the impact of PGD within 30 days after heart transplantation. Methods: Donors’ and recipients’ medical records of 64 consecutive adult cardiac transplantations performed between January 2016 and June 2017 were reviewed. The International Society for Heart and Lung Transplantation (ISHLT) criteria were used to diagnose moderate and severe PGD. Associations of risk factors for combined moderate/severe PGD were assessed with appropriate statistical analyses. Results: Sixty-four patients underwent heart transplantation in this period. Twelve recipients (18.7%) developed severe or moderate PGD. Development of PGD was associated with previous donor cardiopulmonary resuscitation and a history of prior heart surgery in the recipient (P=0.01 and P=0.02, respectively). The 30-day in hospital mortality was similar in both PGD and non-PGD patients. Conclusion: The use of the ISHLT criteria for PGD is important to identify potential risk factor. The development of PGD did not affect short-term survival in our study. More studies should be done to better understand the pathophysiology of PGD. Introduction (PGD center retrospectively donors 3 Methods Donors 6 201 reviewed (ISHLT moderatesevere analyses Results Sixtyfour Sixty four period 18.7% 187 18 7 (18.7% P=0.01 P001 P 0 01 (P=0.0 P002 02 P=0.02 respectively. respectively . respectively) 30day day nonPGD non Conclusion factor shortterm short term 20 18.7 1 (18.7 P=0.0 P00 (P=0. 2 18. (18. P=0. P0 (P=0 (18 P=0 (P= (1 P= (P (

ABSTRACT Introduction: Deep sternal wound infections (DSWI) are so serious and costly that hospital services continue to strive to control and prevent these outcomes. Microcosting is the more accurate approach in economic healthcare evaluation, but there are no studies in this field applying this method to compare DSWI after isolated coronary artery bypass grafting (CABG). This study aims to evaluate the incremental risk-adjusted costs of DSWI on isolated CABG. Methods: This is a retrospective, single-center observational cohort study with a propensity score matching for infected and non-infected patients to compare incremental risk-adjusted costs between groups. Data to homogeneity sample was obtained from a multicentric database, REPLICCAR II, and additional sources of information about costs were achieved with the electronic hospital system (Si3). Inflation variation and dollar quotation in the study period were corrected using the General Market Price Index. Groups were compared using analysis of variance, and multiple linear regression was performed to evaluate the cost drivers related to the event. Results: As expected, infections were costly; deep infection increased the costs by 152% and mediastinitis by 188%. Groups differed among hospital stay, exams, medications, and multidisciplinary labor, and hospital stay costs were the most critical cost driver. Conclusion: In summary, our results demonstrate the incremental costs of a detailed microcosting evaluation of infections on CABG patients in São Paulo, Brazil. Hospital stay was an important cost driver identified, demonstrating the importance of evaluating patients’ characteristics and managing risks for a faster, safer, and more effective discharge. Introduction (DSWI outcomes . (CABG) riskadjusted risk adjusted Methods retrospective singlecenter single center noninfected non groups database II Si3. Si3 Si (Si3) Index variance event Results expected 152 188 188% exams medications labor Conclusion summary Paulo Brazil identified faster safer discharge (CABG (Si3 15 18 (Si 1

Abstract We present an unusual case of a 67-year-old woman with an incidental finding of a cardiac mass on a chest computed tomography. Coronary angiotomography confirmed the diagnosis of right coronary artery aneurysm, with 5.7×5.7 cm. The patient underwent aneurysm resection and coronary bypass surgery, with subsequent histologic study suggestive of arteritis sequelae. Giant coronary artery aneurysms have a high risk of complications and aneurysm exclusion must be beneficial. This is a rare condition that can also be part of a systemic inflammatory disease.

Abstract Introduction: Elevated neutrophil-lymphocyte ratio (NLR) has been associated with poorer outcomes in cyanotic patients undergoing single ventricle palliation. Little is known about this biomarker on patients with tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease. Our objective is to study the impact of preoperative NLR on outcomes of TOF patients undergoing total repair. Methods: This retrospective study included 116 consecutive patients between January 2014 and December 2018. Preoperative NLR was measured from the last complete blood count test before the surgery. Using the cutoff value of 0.80, according to the receiver-operating characteristic (ROC) curve, the sample was divided into two groups (NLR < 0.80 and ≥ 0.80). The primary endpoint was hospital length of stay (LOS). Results: ROC curves showed that higher preoperative NLR was associated with longer hospital LOS, with an area under the curve of 0.801±0.040 (95% confidence interval 0.722 - 0.879; P<0.001). High preoperative NLR was also associated with long intensive care unit (ICU) LOS (P=0.035). Preoperative NLR predicted longer hospital LOS with a sensitivity of 63% and a specificity of 81.4%. Conclusion: Higher preoperative NLR was associated with long ICU and hospital LOS in patients undergoing TOF repair. Introduction neutrophillymphocyte neutrophil lymphocyte palliation TOF, , (TOF) disease repair Methods 11 201 2018 surgery 080 0 80 receiveroperating receiver operating (ROC 0.8 0.80. . 0.80) LOS. (LOS) Results 08010040 801 040 0.801±0.04 95% 95 (95 0722 722 0.72 0.879 0879 879 P<0.001. P0001 P P<0.001 001 P<0.001) (ICU P=0.035. P0035 P=0.035 035 (P=0.035) 63 814 81 4 81.4% Conclusion (TOF 1 20 08 8 0. (LOS 0801004 04 0.801±0.0 9 (9 072 72 0.7 0.87 087 87 P000 P<0.00 00 P003 P=0.03 03 (P=0.035 6 81.4 2 080100 0.801±0. ( 07 7 P00 P<0.0 P=0.0 (P=0.03 81. 08010 0.801±0 P0 P<0. P=0. (P=0.0 0801 0.801± P<0 P=0 (P=0. 0.801 P< P= (P=0 (P= (P

Abstract Introduction: The Technical Performance Score (TPS) was developed and subsequently refined at the Boston Children's Hospital. Our objective was to translate and validate its application in a developing country. Methods: The score was translated into the Portuguese language and approved by the TPS authors. Subsequently, we studied 1,030 surgeries from June 2018 to October 2020. TPS could not be assigned in 58 surgeries, and these were excluded. Surgical risk score was evaluated using Risk Adjustment in Congenital Heart Surgery (or RACHS-1). The impact of TPS on outcomes was studied using multivariable linear and logistic regression adjusting for important perioperative covariates. Results: Median age and weight were 2.2 (interquartile range [IQR] = 0.5-13) years and 10.8 (IQR = 5.6-40) kilograms, respectively. In-hospital mortality was 6.58% (n=64), and postoperative complications occurred in 19.7% (n=192) of the cases. TPS was categorized as 1 in 359 cases (37%), 2 in 464 (47.7%), and 3 in 149 (15.3%). Multivariable analysis identified TPS class 3 as a predictor of longer hospital stay (coefficient: 6.6; standard error: 2.2; P=0.003), higher number of complications (odds ratio [OR]: 1.84; 95% confidence interval [CI]: 1.1-3; P=0.01), and higher mortality (OR: 3.2; 95% CI: 1.4-7; P=0.004). Conclusion: TPS translated into the Portuguese language was validated and showed to be able to predict higher mortality, complication rate, and prolonged postoperative hospital stay in a high-volume Latin-American congenital heart surgery program. TPS is generalizable and can be used as an outcome assessment tool in resource diverse settings. Introduction (TPS Childrens Children s Hospital country Methods authors Subsequently 1030 030 1,03 201 2020 5 excluded or RACHS1. RACHS1 RACHS . RACHS-1) covariates Results 22 2. interquartile IQR [IQR 0.513 0513 0.5 13 0 0.5-13 108 10 8 10. 5.640 5640 5.6 40 6 5.6-40 kilograms respectively Inhospital In 658 6.58 n=64, n64 n n=64 , 64 (n=64) 197 19 7 19.7 n=192 n192 192 (n=192 35 37%, 37 37% (37%) 46 47.7%, 477 47.7% 47 (47.7%) 14 15.3%. 153 15.3% 15 (15.3%) coefficient (coefficient 6.6 66 error P=0.003, P0003 P P=0.003 003 P=0.003) odds OR [OR] 1.84 184 84 95 CI [CI] 1.13 113 1.1 1.1-3 P=0.01, P001 P=0.01 01 P=0.01) (OR 3.2 32 1.47 147 1.4 4 1.4-7 P=0.004. P0004 P=0.004 004 P=0.004) Conclusion rate highvolume high volume LatinAmerican Latin American program settings 103 03 1,0 20 202 RACHS-1 513 0.51 051 05 0. 0.5-1 640 5.64 564 56 5. 5.6-4 65 6.5 n6 n=6 (n=64 19. n=19 n19 (n=19 (37% 47.7 (47.7% 15.3 (15.3% 6. P000 P=0.00 00 [OR 1.8 18 9 [CI 11 1. 1.1- P00 P=0.0 3. 1.4- 1, RACHS- 51 0.5- 5.6- n= (n=6 n=1 n1 (n=1 (37 47. (47.7 15. (15.3 P0 P=0. (n= (3 (47. (15. P=0 (n ( (47 (15 P= (4 (1

Abstract Introduction: The presence of mild to moderate pericardial effusion after cardiac surgery is common and oral medical therapy is usually able to treat it. Larger effusions are less frequent and surgical intervention is usually necessary. However, there are some rare cases of large effusions that are recurrent even after intervention and become challenging to treat. Methods: We describe the case of a patient submitted to coronary artery bypass grafting (CABG) without any intraoperative complications, who was regularly discharged from the hospital. She was referred to our emergency department twice after surgery with large pericardial effusion that was drained. Even after those two interventions and with adequate oral medication, the large effusion recurred. Results: During follow-up, the patient had her symptoms resolved, with no need for further hospital admission. Her echocardiograms after the last intervention showed no pericardial effusion. The present surgical technique demonstrated to be easy to perform, thus it should be considered as a treatment option for these rare cases of large and repetitive effusions, which do not respond to the traditional methods. Conclusions: In challenging cases of recurrent and large pericardial effusions, the pericardial-peritoneal window is an alternative surgical technique that brings clinical improvement and diminishes the risk of cardiac tamponade. Introduction necessary However Methods CABG (CABG complications drained medication recurred Results followup, followup follow up, up follow-up resolved admission perform methods Conclusions pericardialperitoneal peritoneal tamponade

Abstract Introduction: To support the development of practices and guidelines that might help to reduce adverse events related to human factors, we aimed to study the response and perception by members of a cardiovascular surgery team of various error-driven or adverse features that might arise in the operating room (OR). Methods: A previously validated Disruptions in Surgery Index (DiSI) questionnaire was completed by individuals working together in a cardiovascular surgical unit. Results were submitted to reliability analysis by calculating the Cronbach’s alpha coefficient. Non-parametric Kruskal-Wallis test and Dunn’s post-test were performed to estimate differences in perceptions of adverse events or outcomes between the groups (surgeons, nurses, anesthesiologists, and technicians). P<0.05 was considered statistically significant. Results: Cronbach’s alpha reliability coefficients showed consistency within the recommended range for all disruption types assessed in DiSI: an individual’s skill (0.85), OR environment (0.88), communication (0.81), situational awareness (0.92), patient-related disruption (0.89), team cohesion (0.83), and organizational disruption (0.83). Nurses (27.4%) demonstrated significantly higher perception of disruptions than surgeons (25.4%), anesthetists (23.3%), and technicians (23.0%) (P=0.005). Study participants were more observant of their colleagues’ disruptive behaviors than their own (P=0.0001). Conclusion: Our results revealed that there is a tendency among participants to hold a positive self-perception position. DiSI appears to be a reliable and useful tool to assess surgical disruptions in cardiovascular OR teams, identifying negative features that might imperil teamwork and safety in the OR. And human factors training interventions are available to develop team skills and improve safety and efficiency in the cardiovascular OR. Introduction errordriven error driven . (OR) Methods (DiSI unit Cronbachs Cronbach s coefficient Nonparametric Non parametric KruskalWallis Kruskal Wallis Dunns Dunn posttest post surgeons, (surgeons nurses anesthesiologists technicians. technicians) P005 P 0 05 P<0.0 significant individual 0.85, 085 0.85 , 85 (0.85) 0.88, 088 0.88 88 (0.88) 0.81, 081 0.81 81 (0.81) 0.92, 092 0.92 92 (0.92) patientrelated patient 0.89, 089 0.89 89 (0.89) 0.83, 083 0.83 83 (0.83) 0.83. 27.4% 274 27 4 (27.4% 25.4%, 254 25.4% 25 (25.4%) 23.3%, 233 23.3% 23 3 (23.3%) 23.0% 230 (23.0% P=0.005. P0005 P=0.005 005 (P=0.005) colleagues P=0.0001. P00001 P=0.0001 0001 (P=0.0001) Conclusion selfperception self position teams (OR P00 P<0. 08 0.8 8 (0.85 (0.88 (0.81 09 0.9 9 (0.92 (0.89 (0.83 27.4 2 (27.4 25.4 (25.4% 23.3 (23.3% 23.0 (23.0 P000 P=0.00 00 (P=0.005 P0000 P=0.000 000 (P=0.0001 P0 P<0 0. (0.8 (0.9 27. (27. 25. (25.4 23. (23.3 (23. P=0.0 (P=0.00 (P=0.000 P< (0. (27 (25. (23 P=0. (P=0.0 (0 (2 (25 P=0 (P=0. ( P= (P=0 (P= (P

Abstract This study presents the method used for chest reconstruction and treatment of mediastinitis following cardiac surgery at the Heart Institute of the University of São Paulo Medical School. After infection control with antibiotic therapy associated with aggressive surgical debridement and negative pressure wound therapy, chest reconstruction is performed using flaps. The advantages and disadvantages of negative pressure wound therapy are discussed, as well as options for flap-based chest reconstruction according to the characteristics of the patient and sternum. Further studies are needed to provide evidence to support the decisions when facing this great challenge. School flaps discussed flapbased flap based sternum challenge

Abstract Introduction: The coronavirus disease 2019 (COVID-19) has negatively impacted healthcare services worldwide. We hypothesized that the pandemic would affect our case mix and mortality. Our objective was to study this impact. Methods: We retrospectively studied all patients who underwent congenital heart surgeries from March 21st to August 21st in 2019 and 2020 using the institutional electronic database. We compared demographic data, preoperative and postoperative length of stay (LOS), risk stratification using Risk Adjustment for Congenital Heart Surgery (RACHS) classification and outcomes in both periods. Results: We observed a 66.7% decrease in our surgical volume (285 × 95 patients). Patients operated in the pre-pandemic period were older (911.3 [174.8 - 5953.8] days-old) compared to the pandemic period (275 days-old; P<0.05). When the case mix was compared between periods, the percentage of neonatal surgery was increased in the pandemic era (8% × 21.1%; P<0.05), and the number of RACHS 1-2 surgeries decreased significantly (60.7 × 27.4%; P<0.05). Preoperative LOS was increased in the pandemic period (1.2 × 7 days; P=0.001). There was no significant increment in mortality (P=0.1). Two patients tested positive for COVID-19 in the postoperative period and both died. Conclusion: Our program observed a sudden decrease in surgical volume and a consequent increase in surgical complexity. There was a non-significant increment in mortality.

Abstract Introduction: Anemia and blood transfusion are risk factors for morbidity/mortality in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The objective of this study is to analyze the association of blood transfusion with morbidity/mortality in patients undergoing coronary artery bypass grafting (CABG) under CPB in the state of São Paulo, Brazil. Methods: This is a retrospective analysis using the State of São Paulo Registry of Cardiovascular Surgery from November 2013 to August 2014. Blood transfusion was only considered during surgery or within six hours after surgery. Anemia was defined as hematocrit ≤ 37.5%. Patients < 18 years old were excluded. The sample was divided in four groups - Group I (851, no anemia), Group II (200, anemia without blood transfusion), Group III (181, no anemia and transfusion), and Group IV (258, anemia and transfusion). Results: A total of 1,490 patients were included; 639 (42.9%) were anemic and 439 (29.5%) underwent blood transfusion. Group II showed lower composite morbidity (odds ratio [OR] −0.05; confidence interval [CI] −0.27-0.17; P=0.81) than Group III (OR 0.41; CI 0.23-0.59; P=0.018) or Group IV (OR 0.54; CI 0.31-0.77; P=0.016). Group III was at greater risk of mortality (OR 0.73; CI 0.43-1.03; P=0.02) than Group II, which was exposed only to anemia (OR −0.13; CI −0.55-0.29; P=0.75), or Group IV (OR 0.29; CI −0.13-0.71; P=0.539). Conclusion: Anemia in patients undergoing CABG with CPB is bad, but blood transfusion can be worse, increasing at least 50% the risk for mortality and/or morbidity.