Achieving a preoperative haemoglobin above 130 g L-1 may be more important in female than in male patients before cardiac surgery.

Sex-specific preoperative haemoglobin levels and the need for perioperative red cell transfusion in men and women are still debated. Cavalli and colleagues examined the appropriateness of World Health Organization (WHO) anaemia thresholds (haemoglobin <130 g L-1 for males and <120 g L-1 for females) in a retrospective cohort analysis of >6000 adult patients undergoing cardiac surgery with cardiopulmonary bypass. The authors concluded that the WHO anaemia threshold disproportionately disadvantages female cardiac surgery patients, and a preoperative haemoglobin level of at least 130 g L-1 should be targeted in all cardiac surgical patients regardless of sex.

Penny-wise and pound-foolish: the challenges of preoperative anaemia management.

The timely correction of anaemia before major surgery is important for optimising perioperative patient outcomes. However, multiple barriers have precluded the global expansion of preoperative anaemia treatment programmes, including misconceptions about the true cost/benefit ratio for patient care and health system economics. Institutional investment and buy-in from stakeholders could lead to significant cost savings through avoided complications of anaemia and red blood cell transfusions, and through containment of direct and variable costs of blood bank laboratories. In some health systems, billing for iron infusions could generate revenue and promote growth of treatment programmes. The aim of this work is to galvanise integrated health systems worldwide to diagnose and treat anaemia before major surgery.

Visual Blood, a 3D Animated Computer Model to Optimize the Interpretation of Blood Gas Analysis.

Acid-base homeostasis is crucial for all physiological processes in the body and is evaluated using arterial blood gas (ABG) analysis. Screens or printouts of ABG results require the interpretation of many textual elements and numbers, which may delay intuitive comprehension. To optimise the presentation of the results for the specific strengths of human perception, we developed Visual Blood, an animated virtual model of ABG results. In this study, we compared its performance with a conventional result printout. Seventy physicians from three European university hospitals participated in a computer-based simulation study. Initially, after an educational video, we tested the participants' ability to assign individual Visual Blood visualisations to their corresponding ABG parameters. As the primary outcome, we tested caregivers' ability to correctly diagnose simulated clinical ABG scenarios with Visual Blood or conventional ABG printouts. For user feedback, participants rated their agreement with statements at the end of the study. Physicians correctly assigned 90% of the individual Visual Blood visualisations. Regarding the primary outcome, the participants made the correct diagnosis 86% of the time when using Visual Blood, compared to 68% when using the conventional ABG printout. A mixed logistic regression model showed an odds ratio for correct diagnosis of 3.4 (95%CI 2.00-5.79, p < 0.001) and an odds ratio for perceived diagnostic confidence of 1.88 (95%CI 1.67-2.11, p < 0.001) in favour of Visual Blood. A linear mixed model showed a coefficient for perceived workload of -3.2 (95%CI -3.77 to -2.64) in favour of Visual Blood. Fifty-one of seventy (73%) participants agreed or strongly agreed that Visual Blood was easy to use, and fifty-five of seventy (79%) agreed that it was fun to use. In conclusion, Visual Blood improved physicians' ability to diagnose ABG results. It also increased perceived diagnostic confidence and reduced perceived workload. This study adds to the growing body of research showing that decision-support tools developed around human cognitive abilities can streamline caregivers' decision-making and may improve patient care.

Visual Blood, Visualisation of Blood Gas Analysis in Virtual Reality, Leads to More Correct Diagnoses: A Computer-Based, Multicentre, Simulation Study.

Interpreting blood gas analysis results can be challenging for the clinician, especially in stressful situations under time pressure. To foster fast and correct interpretation of blood gas results, we developed Visual Blood. This computer-based, multicentre, noninferiority study compared Visual Blood and conventional arterial blood gas (ABG) printouts. We presented six scenarios to anaesthesiologists, once with Visual Blood and once with the conventional ABG printout. The primary outcome was ABG parameter perception. The secondary outcomes included correct clinical diagnoses, perceived diagnostic confidence, and perceived workload. To analyse the results, we used mixed models and matched odds ratios. Analysing 300 within-subject cases, we showed noninferiority of Visual Blood compared to ABG printouts concerning the rate of correctly perceived ABG parameters (rate ratio, 0.96; 95% CI, 0.92-1.00; p = 0.06). Additionally, the study revealed two times higher odds of making the correct clinical diagnosis using Visual Blood (OR, 2.16; 95% CI, 1.42-3.29; p < 0.001) than using ABG printouts. There was no or, respectively, weak evidence for a difference in diagnostic confidence (OR, 0.84; 95% CI, 0.58-1.21; p = 0.34) and perceived workload (Coefficient, 2.44; 95% CI, -0.09-4.98; p = 0.06). This study showed that participants did not perceive the ABG parameters better, but using Visual Blood resulted in more correct clinical diagnoses than using conventional ABG printouts. This suggests that Visual Blood allows for a higher level of situation awareness beyond individual parameters' perception. However, the study also highlighted the limitations of today's virtual reality headsets and Visual Blood.

Association between iron deficiency and hospitalization rate in community-dwelling older adults: A 3-year prospective observational study of DO-HEALTH.

BACKGROUND: Iron deficiency (ID) is associated with negative health outcomes in older adults. However, data on the impact of ID on the number of hospitalizations and length of hospital stay (LOS) is lacking. OBJECTIVE: To explore the associations between baseline ID and the number of hospitalizations and between baseline ID and at least one LOS ≥5 days in community-dwelling older adults. METHODS: This is a secondary observational analysis of a randomized controlled trial including 2157 community-dwelling adults aged ≥70 years without major diseases at baseline. The main exposure was defined as ID (soluble transferrin receptor [sTfR] concentrations >28.1 nmol/L) at baseline. The primary outcome was the number of hospitalizations over a 3-year follow-up. The secondary outcome was having at least one LOS ≥5 days over the study period among individuals with one or more hospitalizations. Interaction between ID and anemia (hemoglobin <130 g/L for men and <120 g/L for women) was also investigated. RESULTS: Baseline sTfR concentration was determined in 2141 participants (median age 74.0 years). At 3 year, 1497 hospitalizations were reported with an incidence rate of hospitalization of 0.26 per person-year (95% CI: 0.24, 0.28). Overall, baseline ID was associated with a 24% increased incidence rate of hospitalization (incidence rate ratio: 1.24; 95% CI: 1.05, 1.45) over 3 years. This association was independent of anemia status at baseline since the interaction between ID and anemia at baseline was not significant. Moreover, ID was not significantly associated with having a LOS ≥5 days (OR: 1.40; 95% CI: 1.00, 1.97) among participants with at least one hospitalization over 3 years. CONCLUSIONS: ID is associated with increased hospitalization rate and not associated with LOS ≥5 days among generally healthy older adults. Efforts to minimize ID in older adults may improve overall health and optimize healthcare costs.

Recommendations From the International Consensus Conference on Anemia Management in Surgical Patients (ICCAMS).

BACKGROUND: Perioperative anemia has been associated with increased risk of red blood cell transfusion and increased morbidity and mortality after surgery. The optimal approach to the diagnosis and management of perioperative anemia is not fully established. OBJECTIVE: To develop consensus recommendations for anemia management in surgical patients. METHODS: An international expert panel reviewed the current evidence and developed recommendations using modified RAND Delphi methodology. RESULTS: The panel recommends that all patients except those undergoing minor procedures be screened for anemia before surgery. Appropriate therapy for anemia should be guided by an accurate diagnosis of the etiology. The need to proceed with surgery in some patients with anemia is expected to persist. However, early identification and effective treatment of anemia has the potential to reduce the risks associated with surgery and improve clinical outcomes. As with preoperative anemia, postoperative anemia should be treated in the perioperative period. CONCLUSIONS: Early identification and effective treatment of anemia has the potential to improve clinical outcomes in surgical patients.

The impact of direct oral anticoagulants on viscoelastic testing - A systematic review.

Background: In case of bleeding patients and in acute care, the assessment of residual direct oral anticoagulant (DOAC) activity is essential for evaluating the potential impact on hemostasis, especially when a timely decision on urgent surgery or intervention is required. Viscoelastic tests are crucial in a modern goal-directed coagulation management to assess patients' coagulation status. However, the role of viscoelastic test to detect and quantify residual DOAC plasma levels is controversially discussed. The aim of this review was to systematically summarize the evidence of viscoelastic tests for the assessment of residual DOAC activity. Method: PubMed, Embase, Scopus, and the Cochrane Library were searched for original articles investigating the effect of rivaroxaban, apixaban, edoxaban, or dabigatran plasma levels on different viscoelastic tests of the adult population from database inception to December 31, 2021. Results: We included 53 studies from which 31 assessed rivaroxaban, 22 apixaban, six edoxaban, and 29 dabigatran. The performance of viscoelastic tests varied across DOACs and assays. DOAC specific assays are more sensitive than unspecific assays. The plasma concentration of rivaroxaban and dabigatran correlates strongly with the ROTEM EXTEM, ClotPro RVV-test or ECA-test clotting time (CT) and TEG 6s anti-factor Xa (AFXa) or direct thrombin inhibitor (DTI) channel reaction time (R). Results of clotting time (CT) and reaction time (R) within the normal range do not reliable exclude relevant residual DOAC plasma levels limiting the clinical utility of viscoelastic assays in this context. Conclusion: Viscoelastic test assays can provide fast and essential point-of-care information regarding DOAC activity, especially DOAC specific assays. The identification and quantification of residual DOAC plasma concentration with DOAC unspecific viscoelastic assays are not sensitive enough, compared to recommended anti-Xa activity laboratory measurements. Systematic review registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=320629], identifier [CRD42022320629].

Wingless-related integration site (WNT) signaling is activated during the inflammatory response upon cardiac surgery: A translational study.

Objective: Cardiac surgery and the use of cardiopulmonary bypass initiate a systemic inflammatory response. Wingless-related integration site (WNT) signaling is part of the innate immunity and has been attributed a major role in the regulation of inflammation. In preclinical research, WNT-5a may sustain an inflammatory response and cause endothelial dysfunction. Our aim was to investigate WNT signaling after cardiac surgery and its association with postoperative inflammation (Clinicaltrials.gov, NCT04058496). Methods: In this prospective, single-center, observational study, 64 consecutive patients for coronary artery bypass grafting (CABG) ± valve surgery were assigned into three groups: off-pump CABG (n = 28), on-pump CABG (n = 16) and combined valve-CABG surgery (n = 20). Blood samples were acquired before surgery, at intensive care unit (ICU) admission and 4, 8, and 48 h thereafter. Plasma concentrations of WNT-5a and its antagonists Secreted frizzled-related protein 1 (sFRP-1), Secreted frizzled-related protein 5 (sFRP-5), and WNT inhibitory factor 1 (WIF-1) were determined by enzyme-linked immunosorbent assay. In addition, plasma concentrations of six inflammatory cytokines were measured by multiplex immunoassay. Parameters were analyzed for evolution of plasma concentration over time, interactions, intergroup differences, and association with clinical outcome parameters. Results: At baseline, WNT-5a, sFRP-1, and WIF-1 were present in a minimal concentration, while sFRP-5 was elevated. A higher baseline value of WNT-5a, sFRP-5, and WIF-1 resulted in higher subsequent values of the respective parameter. At ICU admission, WNT-5a and sFRP-5 reached their maximum and minimum value, respectively. WIF-1 decreased over time and was lowest 8 h after surgery. sFRP-1 changed minimally over time. While WNT-5a returned to the baseline within 48 h, sFRP-5 and WIF-1 did not reach their baseline value at 48 h. Of the investigated WNT system components, only WIF-1 partially reflected the severity of surgery. WNT-5a and WIF-1 had an impact on postoperative fluid balance and noradrenaline requirement. Conclusion: WNT-5a, sFRP-5, and WIF-1 are part of the systemic inflammatory response after cardiac surgery. WNT-5a peaks immediately after cardiac surgery and returns to baseline within 48 h, presumably modulated by its antagonist sFRP-5. Based on this translational study, WNT-5a antagonism may be further investigated to assess potentially beneficial effects in patients with a dysregulated inflammation after cardiac surgery.

Predictors associated with mortality of extracorporeal life support therapy for acute heart failure: single-center experience with 679 patients.

Background: Extracorporeal life support (ECLS) therapy is increasingly used for cardiac and respiratory support postcardiotomy, refractory cardiogenic shock and cardiopulmonary resuscitation. This study aims to describe in-hospital mortality of patients requiring ECLS, identify independent predictors associated with mortality and analyze changes of mortality over time. Methods: This retrospective study includes all adult ECLS cases at the University Hospital Zurich, a designated ECLS center in Switzerland, in the period 2007 to 2019. Results: ECLS therapy was required in 679 patients (median age 60 years, 27.5% female). In-hospital mortality was 55.5%. Cubic spline interpolation did not detect evidence for a change in mortality over the whole period of 13 years. In-hospital mortality significantly varied between ECLS indications: 70.7% (152/215) for postcardiotomy, 67.9% (108/159) for cardiopulmonary resuscitation, 47.0% (110/234) for refractory cardiogenic shock, and 9.9% (7/71) for lung transplantation and expansive thoracic surgery (P<0.001). Logistic regression modelling showed excellent discrimination in the receiver operating characteristic (ROC) area under the curve (AUC) of 0.89 [95% confidence interval (CI): 0.87-0.92] and identified significant mortality predictors: age, simplified acute physiology score (SAPS) II, as well as new liver failure and each allogenic blood transfusion unit given per day. ECLS after cardiopulmonary resuscitation was associated with significantly higher mortality compared to ECLS for refractory cardiogenic shock. Conclusions: In-hospital mortality of patients treated with ECLS therapy is high. Outcomes have not changed significantly in the observed period. We identified age, SAPS II, new liver failure and each allogenic blood transfusion unit given per day as independent mortality predictors. Knowledge of predictors strongly associated with in-hospital mortality may affect future decisions about ECLS indications and the respective management to use this elaborate therapy more effectively.

Prevalence and incidence of iron deficiency in European community-dwelling older adults: an observational analysis of the DO-HEALTH trial.

BACKGROUND AND AIM: Iron deficiency is associated with increased morbidity and mortality in older adults. However, data on its prevalence and incidence among older adults is limited. The aim of this study was to investigate the prevalence and incidence of iron deficiency in European community-dwelling older adults aged ≥ 70 years. METHODS: Secondary analysis of the DO-HEALTH trial, a 3-year clinical trial including 2157 community-dwelling adults aged ≥ 70 years from Austria, France, Germany, Portugal and Switzerland. Iron deficiency was defined as soluble transferrin receptor (sTfR) > 28.1 nmol/L. Prevalence and incidence rate (IR) of iron deficiency per 100 person-years were examined overall and stratified by sex, age group, and country. Sensitivity analysis for three commonly used definitions of iron deficiency (ferritin < 45 µg/L, ferritin < 30 µg/L, and sTfR-ferritin index > 1.5) were also performed. RESULTS: Out of 2157 participants, 2141 had sTfR measured at baseline (mean age 74.9 years; 61.5% women). The prevalence of iron deficiency at baseline was 26.8%, and did not differ by sex, but by age (35.6% in age group ≥ 80, 29.3% in age group 75-79, 23.2% in age group 70-74); P < 0.0001) and country (P = 0.02), with the highest prevalence in Portugal (34.5%) and the lowest in France (24.4%). As for the other definitions of iron deficiency, the prevalence ranged from 4.2% for ferritin < 30 µg/L to 35.3% for sTfR-ferritin index > 1.5. Occurrences of iron deficiency were observed with IR per 100 person-years of 9.2 (95% CI 8.3-10.1) and did not significantly differ by sex or age group. The highest IR per 100 person-years was observed in Austria (20.8, 95% CI 16.1-26.9), the lowest in Germany (6.1, 95% CI 4.7-8.0). Regarding the other definitions of iron deficiency, the IR per 100 person-years was 4.5 (95% CI 4.0-4.9) for ferritin < 45 µg/L, 2.4 (95% CI 2.2-2.7) for ferritin < 30 µg/L, and 12.2 (95% CI 11.0-13.5) for sTfR-ferritin index > 1.5. CONCLUSIONS: Iron deficiency is frequent among relatively healthy European older adults, with people aged ≥ 80 years and residence in Austria and Portugal associated with the highest risk.

Prospective, randomized, controlled, double-blind, multi-center, multinational study on the safety and efficacy of 6% Hydroxyethyl starch (HES) sOlution versus an Electrolyte solutioN In patients undergoing eleCtive abdominal Surgery: study protocol for the PHOENICS study.

BACKGROUND: Hydroxyethyl starch (HES) solutions are used for volume therapy to treat hypovolemia due to acute blood loss and to maintain hemodynamic stability. This study was requested by the European Medicines Agency (EMA) to provide more evidence on the long-term safety and efficacy of HES solutions in the perioperative setting. METHODS: PHOENICS is a randomized, controlled, double-blind, multi-center, multinational phase IV (IIIb) study with two parallel groups to investigate non-inferiority regarding the safety of a 6% HES 130 solution (Volulyte 6%, Fresenius Kabi, Germany) compared with a crystalloid solution (Ionolyte, Fresenius Kabi, Germany) for infusion in patients with acute blood loss during elective abdominal surgery. A total of 2280 eligible patients (male and female patients willing to participate, with expected blood loss ≥ 500 ml, aged > 40 and ≤ 85 years, and ASA Physical status II-III) are randomly assigned to receive either HES or crystalloid solution for the treatment of hypovolemia due to surgery-induced acute blood loss in hospitals in up to 11 European countries. The dosing of investigational products (IP) is individualized to patients' volume needs and guided by a volume algorithm. Patients are treated with IP for maximally 24 h or until the maximum daily dose of 30 ml/kg body weight is reached. The primary endpoint is the treatment group mean difference in the change from the pre-operative baseline value in cystatin-C-based estimated glomerular filtration rate (eGFR), to the eGFR value calculated from the highest cystatin-C level measured during post-operative days 1-3. Further safety and efficacy parameters include, e.g., combined mortality/major post-operative complications until day 90, renal function, coagulation, inflammation, hemodynamic variables, hospital length of stay, major post-operative complications, and 28-day, 90-day, and 1-year mortality. DISCUSSION: The study will provide important information on the long-term safety and efficacy of HES 130/0.4 when administered according to the approved European product information. The results will be relevant for volume therapy of surgical patients. TRIAL REGISTRATION: EudraCT 2016-002162-30 . ClinicalTrials.gov NCT03278548.

Physicians' perceptions of two ways of algorithm presentation: graphic versus text-based approach.

Acute bleeding during surgery or after trauma harms patients, and challenges involved physicians. Protocols and cognitive aids can help in such situations. This dual-centre study investigated physicians' opinions regarding two ways to present cognitive aids, graphic 'Haemostasis Traffic Light' and text-based, using the example of a coagulation management algorithm to identify the strengths and limitations of both presentation modalities. Using qualitative research methods, we identified recurring answer patterns and derived major topics and subthemes through inductive coding. Eighty-four physicians participated. We assigned each half randomly to one of the cognitive aids (graphic/text-based) and determined 447 usable statements. We qualitatively deduced the importance of having a cognitive aid for physicians. Furthermore, it is noticeable that the graphic group made more positive comments (154 of 242 (64%) statements), while the text-based participants made more negative annotations (126 of 205 (61%) statements), suggesting a generally stronger approval of this cognitive aid. Practitioner summary: This qualitative study provides an overview of physicians` positive and negative perceptions regarding two presentation ways for a coagulation management algorithm. Participants perceived the graphic method created according to user-centred design principles more positively. The analysis reveals components that an ideal algorithm should have to help streamline the decision-making process.

Prevalence and outcome of contrast-induced nephropathy in major trauma patients.

BACKGROUND: Contrast-induced nephropathy (CIN) has been well investigated in patients undergoing coronary angiography, but not in trauma patients. The main aim of this study was to determine the prevalence and to investigate independent risk factors for the development of CIN. METHODS: Between 2008 and 2014, all pre-hospital intubated major trauma patients with documented serum creatinine levels (SCr) undergoing a contrast-enhanced whole-body CT at admission were retrospectively analyzed. CIN was defined as a relative increase in SCr > 25% over the baseline value or an absolute SCr increase of > 44 µmol/l within 72 h. Univariate and multivariable regression analyses were performed to identify significant risk factors. A p value of < 0.01 was considered statistically significant and a p value of 0.01-0.049 suggested evidence. RESULTS: Of 284 analyzed patients, 41 (14%) met the criteria for CIN. There is suggestive evidence that age and lactate level influenced the development of CIN. Six patients (15%) had hemodialysis in the CIN-group and eight (3.3%) in the group without CIN. Complication and mortality rate was higher in patients with CIN (71% vs. 56% and 32% vs. 23%, respectively). CIN was not an independent risk factor for complications or mortality while controlling for age, gender, injury severity score, and lactate level. The length of stay was not affected by CIN. CONCLUSION: CIN occurs frequently in trauma patients, but is not an independent risk factor for complications or mortality. Therefore, contrast enhanced whole-body CT can safely be performed in trauma patients.

Iron deficiency and biomarkers of inflammation: a 3-year prospective analysis of the DO-HEALTH trial.

BACKGROUND: The longitudinal association between iron deficiency and inflammatory biomarkers levels has not been fully explored among relatively healthy older adults. AIMS: To assess whether iron deficiency at baseline and at any yearly follow-up time point, with or without anemia, was associated with changes from baseline in high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) levels over 3 years. METHODS: This is a post-hoc observational analysis of DO-HEALTH, a double-blind, randomized controlled trial including 2157 European community-dwelling adults age 70+. The outcomes were changes from baseline in hs-CRP and IL-6 levels, measured at 12, 24, and 36 months of follow-up. Iron deficiency was defined by soluble transferrin receptor levels > 28.1 nmol/L and baseline anemia by hemoglobin levels < 130 g/L for men and < 120 g/L for women. RESULTS: In total, 2141 participants were included in the analyses (mean age: 74.9 years, 61.5% of women, 26.8% with iron deficiency). Baseline iron deficiency was associated with greater increase in IL-6 levels (mean difference in change: 0.52 ng/L, 95%CI 0.03-1.00, P = .04) over 3 years. Iron deficiency at any yearly time point was associated with higher increases in hs-CRP (mean difference in change: 1.62 mg/L, 95%CI 0.98-2.26, P < .001) and IL-6 levels (mean difference in change: 1.33 ng/L, 95%CI 0.87-1.79, P < .001) over 3 years. No significant interaction between iron deficiency and anemia was found, suggesting that the results are independent of the anemic status. CONCLUSIONS: These findings suggest that iron deficiency may play a role in low-grade chronic inflammation among relatively healthy older adults.

Peri-operative blood transfusion in elective major surgery: incidence, indications and outcome - an observational multicentre study.

BACKGROUND: Patients' demographic and epidemiological characteristics, local variations in clinicians' knowledge and experience and types of surgery can influence peri-operative transfusion practices. Sharing data on transfusion practices and recipients may improve patients' care and implementation of Patient Blood Management (PBM). MATERIALS AND METHODS: This was a multicentre, prospective, observational, cross-sectional study that included 61 centres. Clinical and transfusion data of patients undergoing major elective surgery were collected; transfusion predictors and patients' outcomes were analysed. RESULTS: Of 6,121 patients, 1,579 (25.8%) received a peri-operative transfusion. A total of 5,812 blood components were transfused: red blood cells (RBC), fresh-frozen plasma and platelets in 1,425 (23.3%), 762 (12.4%) and 88 (1.4%) cases, respectively). Pre-operative anaemia was identified in 2,019 (33%) patients. Half of the RBC units were used by patients in the age group 45-69 years. Specific procedures with the highest RBC use were coronary artery bypass grafting (16.9% of all units) and hip arthroplasty (14.9%). Low haemoglobin concentration was the most common indication for intra-operative RBC transfusion (57%) and plasma and platelet transfusions were mostly initiated for acute bleeding (61.3% and 61.1%, respectively). The RBC transfusion rate in study centres varied from 2% to 72%. RBC transfusion was inappropriate in 99% (n=150/151) of pre-operative, 23% (n=211/926) of intra-operative and 43% (n=308/716) of post-operative RBC transfusion episodes. Pre-operative haemoglobin, increased blood loss, open surgery and duration of surgery were the main independent predictors of intra-operative RBC transfusion. Low pre-operative haemoglobin concentration was independently associated with post-operative pulmonary complications. CONCLUSIONS: These findings identified areas for improvement in peri-operative transfusion practice and PBM implementation in Turkey.

Cardiovascular Safety of Clonidine and Dexmedetomidine in Critically Ill Patients after Cardiac Surgery.

PURPOSE: The aim of this retrospective study was to assess the haemodynamic adverse effects of clonidine and dexmedetomidine in critically ill patients after cardiac surgery. METHODS: 2769 patients were screened during the 30-month study period. Heart rate (HR), mean arterial pressure (MAP), and norepinephrine requirements were assessed 3-hourly during the first 12 hours of the continuous drug infusion. Results are given as median (interquartile range) or numbers (percentages). RESULTS: Patients receiving clonidine (n = 193) were younger (66 (57-73) vs 70 (63-77) years, p=0.003) and had a lower SAPS II (35 (27-48) vs 41 (31-54), p=0.008) compared with patients receiving dexmedetomidine (n = 141). At the start of the drug infusion, HR (90 (75-100) vs 90 (80-105) bpm, p=0.028), MAP (70 (65-80) vs 70 (65-75) mmHg, p=0.093), and norepinephrine (0.05 (0.00-0.11) vs 0.12 (0.03-0.19) mcg/kg/min, p < 0.001) were recorded in patients with clonidine and dexmedetomidine. Bradycardia (HR < 60 bpm) developed in 7.8% with clonidine and 5.7% with dexmedetomidine (p=0.51). Between baseline and 12 hours, norepinephrine remained stable in the clonidine group (0.00 (-0.04-0.02) mcg/kg/min) and decreased in the dexmedetomidine group (-0.03 (-0.10-0.02) mcg/kg/min, p=0.007). CONCLUSIONS: Dexmedetomidine and the low-cost drug clonidine can both be used safely in selected patients after cardiac surgery.