Phase of care mortality analysis and failure to rescue in a Norwegian cardiothoracic unit.

Objectives. Two tools to categorize and present quality data, phase of care mortality analysis (POCMA) and failure to rescue (FTR) have been introduced in the cardiothoracic surgical environment, but not tested in Scandinavia. We aimed to investigate whether these tools could be used in a Norwegian patient population and to increase the understanding of why patients die after cardiac surgery. Design. A group of four, including one senior cardiothoracic surgeon and one senior anesthesiologist, scrutinized deaths within 30 days after cardiac surgery at the Clinic of Cardiothoracic Surgery, St. Olav's University Hospital, Norway between February 2012-October 2015 in line with the POCMA-methodology. We used the clinic's internal register to identify patients and utilized all available written information from each patient course. We decided whether each death was surgeon dependent, FTR or a result of a multifactorial etiology, and evaluated the strength of our decisions. Results. We identified 51 deaths out of 1983 operations in our study period, giving unadjusted mortality of 2.6%. Nine deaths were classified as surgeon dependent, 3 FTR and 39 multifactorial. Conclusions. POCMA- and FTR-analyses can be carried out in clinical data which is well documented. The operating surgeon is in many cases not responsible for operative mortality, very few die due to FTR, but most patients die due to a multifactorial etiology.

Perioperative Factors Associated With Changes in Troponin T During Coronary Artery Bypass Grafting.

OBJECTIVE: Investigate important clinical and operative variables associated with increases in cardiac troponin T (cTnT) as indicators of myocardial injury after coronary artery bypass grafting (CABG). DESIGN: Prospective cohort study. SETTING: Single university hospital. PARTICIPANTS: The study comprised 626 patients undergoing isolated CABG from April 2008 through April 2010 with a validation cohort (n = 686) from 2015-2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Perioperative variables were registered prospectively. The extent of diffuse coronary atherosclerosis and significant stenoses were assessed with preoperative coronary angiography. Mixed model analysis was used to construct a statistical model explaining the course of cTnT concentrations. The model was adjusted for preoperative and intraoperative/postoperative myocardial infarction (MI) for independent assessment of additional variables. Clinical factors associated with increased cTnT concentrations during and after CABG were longer duration of cardiopulmonary bypass (p < 0.001), higher preoperative creatinine (p < 0.001), New York Heart Association functional classification IV (p = 0.006), reduced LVEF (p = 0.034), higher preoperative C-reactive protein (p = 0.049), and intraoperative/postoperative MI (p < 0.001). Factors associated with decreasing cTnT concentrations during CABG were higher BSA (p < 0.001) and a recent preoperative MI (p < 0.001). The extent of diffuse coronary atherosclerosis and significant stenoses were not associated with changes in cTnT (p = 0.35). Results were similar in the validation cohort. CONCLUSIONS: Left ventricular ejection fraction, New York Heart Association classification, kidney function, inflammation status, duration of cardiopulmonary bypass, body surface area, and preoperative MI were associated with the cTnT rise-and-fall pattern related to myocardial injury after CABG. Information regarding these variables may be valuable when using cTnT in the diagnostic workup of postoperative MI.

A Preoperative Multimarker Approach to Evaluate Acute Kidney Injury After Cardiac Surgery.

OBJECTIVE: To investigate whether a multimarker strategy combining preoperative biomarkers representing distinct pathophysiologic pathways enhances preoperative risk assessment of acute kidney injury after cardiac surgery (CSA-AKI) and increases knowledge of underlying pathogenesis. DESIGN: Prospective, cohort study. SETTING: Single-center tertiary referral hospital. PARTICIPANTS: The study comprised 1,015 adults undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: CSA-AKI was defined as≥50% increase in serum creatinine concentration, absolute increase≥26 µmol/L, or new requirement for dialysis. Preoperative and perioperative information until hospital discharge was recorded. Preoperative plasma levels of C-reactive protein, terminal complement complex, neopterin, lactoferrin, N-terminal pro-brain natriuretic peptide, and cystatin C were determined using enzyme immunoassays. Biomarkers were selected based on causal hypotheses of underlying mechanisms and were related to inflammatory, hemodynamic, or renal signaling pathways. MEASUREMENTS AND MAIN RESULTS: One hundred patients (9.9%) developed CSA-AKI. Higher baseline plasma concentrations of neopterin and N-terminal pro-brain natriuretic peptide were associated independently with CSA-AKI (p = 0.04 and p<0.001, respectively). Lower baseline plasma lactoferrin concentrations were observed in patients with CSA-AKI (p = 0.05). Compared with clinical risk assessment, addition of these biomarkers provided a slight, but significant, increment in predictive utility (area under the curve 0.81-0.83, likelihood ratio test p<0.001). A net of 12% of patients were reclassified correctly, and improved prediction was demonstrated, especially in patients with intermediate risk (56% correct reclassification). CONCLUSIONS: Preoperative hemodynamic, renal, and immunologic function play central roles in the pathogenesis of CSA-AKI. These findings add evidence to the potential of a multimarker approach to improve preoperative prediction of CSA-AKI.

Prediction of bleeding after cardiac surgery: comparison of model performances: a prospective observational study.

OBJECTIVES: Primary aims were to (1) perform external validation of the Papworth Bleeding Risk Score, and (2) compare the usefulness of the Dyke et al universal definition of perioperative bleeding with that used in the Papworth Bleeding Risk Score. A secondary aim was to use a locally developed logistic prediction model for severe postoperative bleeding to investigate whether prediction could be improved with inclusion of the variable "surgeon" or selected intraoperative variables. DESIGN: Single-center prospective observational study. SETTING: University hospital. PARTICIPANTS: 7,030 adults undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Papworth Bleeding Risk Score could identify the group of patients with low risk of postoperative bleeding, with negative predictive value of 0.98, when applying the Papworth Score on this population. The positive predictive value was low; only 15% of the patients who were rated high risk actually suffered from increased postoperative bleeding when using the Papworth Score on this population. Using the universal definition of perioperative bleeding proposed by Dyke et al, 28% of patients in the Papworth high-risk group exceeded the threshold of excessive bleeding in this population. The local models showed low ability for discrimination (area under the receiver operating characteristics curve<0.75). Addition of the factor "surgeon" or selected intraoperative variables did not substantially improve the models. CONCLUSION: Prediction of risk for excessive bleeding after cardiac surgery was not possible using clinical variables only, independent of endpoint definition and inclusion of the variable "surgeon" or of selected intraoperative variables. These findings may be due to incomplete understanding of the causative factors underlying excessive bleeding.

The Precision of Pulmonary Artery Catheter Bolus Thermodilution Cardiac Output Measurements Varies With the Clinical Situation.

OBJECTIVE: To investigate the effects of ventilatory mode, injectate temperature, and clinical situation on the precision of cardiac output measurements. DESIGN: Randomized, prospective observational study. SETTING: Single university hospital. PARTICIPANTS: Forty patients undergoing planned cardiac surgery, receiving a pulmonary artery catheter according to institutional routine. INTERVENTIONS: Cardiac output was measured at 4 predefined time points during the perioperative patient course, twice during controlled and twice during spontaneous ventilation, using 2 blocks of 8 measurement replications with cold and tepid injectate in random order. MEASUREMENTS AND MAIN RESULTS: The data were analyzed using a hierarchical linear mixed model. Clinical precision was determined as half the width of the 95% confidence interval for the underlying true value. The single-measurement precision measured in 2 different clinical situations for each temperature/ventilation combination was 8% to 10%, 11% to 13%, 13% to 15%, and 23% to 24% in controlled ventilation with cold injectate, controlled ventilation with tepid injectate, spontaneous breathing with cold injectate, and spontaneous breathing with tepid injectate, respectively. Tables are provided for the number of replications needed to achieve a certain precision and for how to identify significant changes in cardiac output. CONCLUSIONS: Clinical precision of cardiac output measurements is reduced significantly during spontaneous relative to controlled ventilation. The differences in precision between repeated measurement series within the temperature/ventilation combinations indicate influence of other situation-specific factors not related to ventilatory mode. Compared with tepid injectate in patients breathing spontaneously, the precision is 3-fold better with cold injectate and controlled ventilation.

Comparison of three point-of-care testing devices to detect hemostatic changes in adult elective cardiac surgery: a prospective observational study.

BACKGROUND: Bleeding complications in cardiac surgery may lead to increased morbidity and mortality. Traditional blood coagulation tests are not always suitable to detect rapid changes in the patient's coagulation status. Point-of-care instruments such as the TEG (thromboelastograph) and RoTEM (thromboelastometer) have been shown to be useful as a guide for the clinician in the choice of blood products and they may lead to a reduction in the need for blood transfusion, contributing to better patient blood management. METHODS: The purpose of this study was to evaluate the ability of the TEG, RoTEM and Sonoclot instruments to detect changes in hemostasis in elective cardiac surgery with cardiopulmonary bypass and to investigate possible correlations between variables from these three instruments and routine hematological coagulation tests. Blood samples from thirty-five adult patients were drawn before and after surgery and analyzed in TEG, RoTEM, Sonoclot and routine coagulation tests. Data were compared using repeated measures analysis of variance and Pearson's test for linear correlation. RESULTS: We found significant changes for all TEG variables after surgery, for three of the RoTEM variables, and for one variable from the Sonoclot. There were significant correlations postoperatively between plasma fibrinogen levels and variables from the three instruments. CONCLUSIONS: TEG and RoTEM may be used to detect changes in hemostasis following cardiac surgery with CPB. Sonoclot seems to be less suitable to detect such changes. Variables from the three instruments correlated with plasma fibrinogen and could be used to monitor treatment with fibrinogen concentrate.

How can we best predict acute kidney injury following cardiac surgery?: a prospective observational study.

BACKGROUND: Several models for predicting acute kidney injury following cardiac surgery have been published, and various end-point definitions have been used. OBJECTIVES: Our aim was to investigate how acute kidney injury following cardiac surgery could be most accurately predicted. DESIGN: Single-centre prospective observational study. SETTING: St Olav's University Hospital, Trondheim, Norway, from 2000 to 2007. PATIENTS: All 5029 adult patients undergoing cardiac surgery were considered eligible for participation. Patients who required preoperative dialysis and patients with missing information on preoperative or maximum postoperative serum creatinine concentration were excluded (n=51). A total of 4978 patients were entered into the statistical analyses. MAIN OUTCOME MEASURES: Logistic regression with bootstrapping methods was applied for model development and validation, together with the area under the receiver operating characteristic curve and Hosmer-Lemeshow test. We tested different end-points, exchanged serum creatinine concentration with creatinine clearance or estimated glomerular filtration rate and added intraoperative variables. The main end-point was at least 50% increase in serum creatinine concentration, an increase in concentration by at least 26.4 µmol l(-1) (0.3 mg dl(-1)) or a new requirement for dialysis after surgery. RESULTS: The final model consisted of 11 preoperative predictors of acute kidney injury: age, BMI, lipid-lowering treatment, hypertension, peripheral vascular disease, chronic pulmonary disease, haemoglobin concentration, serum creatinine concentration, previous cardiac surgery, emergency operation and operation type. The area under the receiver operating characteristic curve was 0.819 (95% confidence interval 0.801 to 0.837), and the Hosmer-Lemeshow test P value was 0.17. Exchanging serum creatinine concentration with glomerular filtration rate or creatinine clearance slightly reduced model discrimination and the addition of intraoperative variables improved discrimination somewhat. Slight end-point definition changes had little impact. CONCLUSION: The risk of acute kidney injury can be accurately predicted using preoperative variables. Serum creatinine concentration was more accurate than estimated glomerular filtration rate or creatinine clearance. Intraoperative variables slightly improved the model, but did not seem to outweigh the advantages of a preoperative model.

Tranexamic acid reduces blood transfusions in elderly patients undergoing combined aortic valve and coronary artery bypass graft surgery: a randomized controlled trial.

OBJECTIVE: To evaluate the effects of tranexamic acid on postoperative blood loss and transfusion requirements in elderly patients undergoing combined aortic valve replacement and coronary artery bypass graft surgery (CABG). DESIGN: A prospective, randomized, double-blinded, placebo-controlled, parallel-group trial. SETTING: A university hospital (single institution). PARTICIPANTS: Sixty-four patients 70 years or older undergoing combined aortic valve replacement and CABG surgery were included. One patient was withdrawn from the study after randomization by the attending surgeon because of a change in the surgical procedure. The remaining 63 patients were analyzed as intention to treat. INTERVENTIONS: The included patients were randomized to treatment with either tranexamic acid, 10 mg/kg, as a bolus injection before surgery followed by 1 mg/kg/h as an infusion during surgery, or a corresponding volume of 0.9% sodium chloride. MEASUREMENTS AND MAIN RESULTS: Postoperative blood loss was recorded for 16 hours. The transfusion of blood products was recorded during the entire hospital stay. The number of packed red cell transfusions given to the patients was significantly lower in the tranexamic acid group compared with the placebo group (median, 3.0 [interquartile range, 2-5] v 5.0 [3-7], p = 0.049). CONCLUSION: Tranexamic acid reduced the number of packed red cell transfusions given to patients 70 years or older undergoing combined aortic valve replacement and CABG surgery.

Preoperative and intraoperative prediction of risk of cardiac dysfunction following open heart surgery.

CONTEXT: Cardiac dysfunction following open heart surgery is a major determinant of subsequent morbidity and mortality. OBJECTIVES: To develop a specific risk prediction model for postoperative cardiac dysfunction based on preoperative variables, to investigate whether prediction could be improved by inclusion of selected intraoperative variables and to compare our model with five previously published risk scores. DESIGN: Single-centre prospectively collected data. SETTING: Tertiary care centre, Middle Norway. PATIENTS: Four thousand nine hundred and eighty-nine patients (all eligible) undergoing open cardiac surgery from 2000 to 2007. MAIN OUTCOME MEASURES: Logistic regression models for postoperative cardiac dysfunction: predictive accuracy/calibration, discrimination as shown by area under the receiver operating characteristics curve, internal validity as indicated by bootstrapping, comparison of goodness-of-fit with predictions based on alternative risk scores. RESULTS: The preoperative model included chronic cardiac insufficiency, previous myocardial infarction, previous cardiac operation, pulmonary hypertension, renal dysfunction, low haemoglobin concentration, urgent operation and operation type other than isolated coronary artery bypass surgery. The area under the curve was 0.838 [95% confidence interval (CI) 0.812-0.864]. Risk prediction was accurate apart from a slight overestimation in the 2% of highest risk patients. Inclusion of a few intraoperative variables (inotropic or vasoconstrictor drugs, plasma or red cell transfusion) improved the model slightly, increasing the area under the curve to 0.875 (95% CI 0.854-0.896) or 0.890 (95% CI 0.863-0.902) for two equivalent models. On the basis of estimated shrinkage factors of 0.94, 0.97 and 0.98, respectively, the models should behave with 6% or less error in future datasets. Our preoperative model was significantly better than the previously published risk scores (P < 0.0002 for comparison of area under the curves). CONCLUSION: The preoperative model including variables obtained easily in routine clinical work performed well and was improved only slightly by inclusion of intraoperative variables. Performance was better than those of the five previously published risk scores.

Management of cardiac patients for non-cardiac surgery.

Patients with cardiac diseases undergoing non-cardiac surgery experience more perioperative problems than the others. The prevention of these problems includes proper preoperative evaluation of patients, careful intraoperative management and postoperative surveillance. Preoperative examination of such patients, including echocardiography if necessary, is crucial. The need for preoperative medication (e.g. beta-blockers, statins) ought to be carefully considered. Intraoperative management requires goal-directed haemodynamic monitoring and therapy as well as proper fluid infusion. There are no data confirming the superiority of general over regional anaesthesia in such patients. However, lower incidence of pulmonary complications and lower mortality rates were observed after regional blocks.

Initial experience with the Freedom Solo® stentless aortic valve in a low volume centre.

OBJECTIVES: Freedom Solo is a stentless biological aortic valve which is implanted supra-annularly with a single suture line. An increased risk of postoperative thrombocytopenia in the early postoperative period has been reported in recent studies. In our study we evaluated postoperative haemodynamic performance and thrombocyte-levels. DESIGN: Thirty seven patients who underwent valve implantation of the Sorin Freedom Solo stentless valve were included. The haemodynamic performance of the valve was evaluated by transthoracic echocardiography postoperatively at the fourth day (mean) and after a median of 4.2 months. RESULTS: The mean gradient (mmHg) of Freedom Solo was 7.5 at four days and 8.6 at 4.2 months. Postoperatively no patient had more than grade 1 leakage. Seven percent of the patients had a reduction of thrombocytes to less than 20% of the preoperative level. Seventy six percent had a minimum postoperative thrombocyte level less than 100*10(9)/L. The 30 days mortality in our patient material was zero. CONCLUSIONS: Implantation of the Freedom Solo valve was uncomplicated in our experience. Favourable transvalvular gradients and no significant leaks were found. In accordance with the literature, we found a high percentage of patients having a postoperative level of thrombocytes less than 100*10(9)/L after implantation of Freedom Solo.

Patterns of smoking behaviour in patients following cardiac surgery. A prospective study.

OBJECTIVES: To describe patterns of smoking behaviour in patients undergoing cardiac surgery. DESIGN: A prospective population-based study of patients undergoing cardiac surgery between September 2004 and September 2005. Smoking behaviour and socio-demographic variables were obtained by questionnaires at baseline, six and 12 months after surgery. RESULTS: At baseline 534 patients (median age 69 years, 23% females) were included, 89% responded after six and 12 months. At baseline 14% (n = 74) were current smokers, 59% (n = 316) were former smokers and 27% (n = 143) had never smoked. At six months 8% were current smokers (n = 36) while 9% (n = 40) were current smokers at 12 months. A total of nine smokers had relapsed at 12 months. CONCLUSION: About half of the current smokers gave up smoking after cardiac surgery. Changes in smoking behaviour were most likely to occur during the first six months. This supports that smoking cessation interventions should continue after discharge. Cardiac surgery can serve as a teachable moment; an opportunity to encourage patients to give up smoking and prevent relapses among those who stopped smoking before surgery.

[Non-cardiac surgery in patients with cardiac disease]. / Ikke-kardial kirurgi hos hjertesyke pasienter.

BACKGROUND: Patients with cardiac disease have a higher incidence of cardiovascular events after non-cardiac surgery than those without such disease. This paper provides an overview of perioperative examinations and treatment. MATERIAL AND METHODS: Own experience and systematic literature search through work with European guidelines constitute the basis for recommendations given in this article. RESULTS: Beta-blockers should not be discontinued before surgery. High-risk patients may benefit from beta-blockers administered before major non-cardiac surgery. Slow dose titration is recommended. Echocardiography should be performed before preoperative beta-blockade to exclude latent heart failure. Statins should be considered before elective surgery and coronary intervention (stenting or surgery) before high-risk surgery. Otherwise, interventions should be evaluated irrespective of planned non-cardiac surgery. Patients with unstable coronary syndrome should only undergo non-cardiac surgery on vital indications. Neuraxial techniques are optimal for postoperative pain relief and thus for postoperative mobilization. Thromboprophylaxis is important, but increases the risk of epidural haematoma and requires systematic follow-up with respect to diagnostics and treatment. INTERPRETATION: Little evidence supports the use of different anaesthetic methods in cardiac patients that undergo non-cardiac surgery than in other patients. Stable circulation, sufficient oxygenation, good pain relief, thromboprophylaxis, enteral nutrition and early mobilization are important factors for improving the perioperative course. Close cooperation between anaesthesiologist, surgeon and cardiologist improves logistics and treatment.

Sonoclot analysis in coronary artery surgery: a comparison between patients with unstable coronary artery disease treated with enoxaparin before surgery and patients with stable coronary artery disease not treated with enoxaparin.

OBJECTIVES: To investigate whether perioperative Sonoclot analyses could identify differences in hemostatic function between a group of patients with unstable coronary artery disease treated with low-molecular-weight heparin until the evening before surgery and a group of patients with stable coronary artery disease not treated with low-molecular-weight heparin. DESIGN: Prospective and observational investigation. SETTING: A university hospital, single institution. PARTICIPANTS: Patients scheduled for coronary artery bypass surgery. INTERVENTIONS: Blood samples for Sonoclot analysis were drawn preoperatively, 5 minutes after the administration of heparin, immediately after and 20 minutes after cardiopulmonary bypass was established, and 30 minutes and 3 and 20 hours after the end of surgery in a group of patients with unstable coronary artery disease and a group of patients with stable coronary artery disease. MEASUREMENTS AND MAIN RESULTS: The Sonoclot variables sonACT, coagulation rate, time to peak, amplitude of the peak, and R3 were recorded. The sonACT was significantly lower in the enoxaparin group compared with the control group, whereas the coagulation rate was significantly higher in the enoxaparin group. There were no statistically significant differences in time to peak, amplitude of the peak, and R3 between the 2 study groups. CONCLUSIONS: The presence of a hypercoagulable state in patients with unstable coronary artery disease is indicated by the significantly higher coagulation rate observed in this group compared with the control group. Further larger studies are needed for evaluation of the usefulness of Sonoclot analysis in the monitoring of hemostatic function in patients with unstable coronary artery disease.

Transfusion of red blood cells in coronary surgery: is there an effect on long-term mortality when adjusting for risk factors and postoperative complications?

OBJECTIVES: The aim of this study was to compare long-term mortality in patients undergoing primary isolated coronary artery bypass grafting who received ≥1 units of red blood cells (RBCs) or no RBCs. We hypothesized that a possible difference in long-term mortality was due to preoperative morbidity and/or postoperative morbidity. METHODS: This prospective cohort study, part of the Cardiac Surgery Outcome Study (CaSOS) at St. Olavs University Hospital, Trondheim, Norway, included patients operated on from 2000 through 2014 (n = 4014) and excluded those with large intra- or postoperative blood loss or 30-day mortality. Observed mortality from 30 days to 15 years postoperatively was compared between patients who received RBC transfusion and those who did not. Cox regression analysis was performed with unadjusted models, adjusting for pre- and intraoperative covariates, and with further adjustment for postoperative complications. Sensitivity analyses were performed with propensity score matching or including 30-day mortality. RESULTS: The unadjusted hazard ratio (HR) for long-term mortality was 2.10 (1.81-2.43; P < 0.01) for transfused patients. After adjusting for pre- and intraoperative variables, the HR was 1.26 (1.04-1.53; P = 0.02). With further adjustment for postoperative complications, RBC transfusion was no longer significant and the HR was 1.19 (0.98-1.44; P = 0.08). These results were supported by the sensitivity analyses. CONCLUSIONS: The study indicated that most of the association between RBC transfusion and long-term mortality following primary isolated coronary artery bypass grafting was due to confounders, especially from postoperative complications.

Long-term health-related quality of life and survival after cardiac surgery: A prospective study.

OBJECTIVES: Health-related quality of life (HRQOL) is an important end point after cardiac surgery, particularly in patients of older age. However, prospective long-term studies describing the trajectory of HRQOL after cardiac surgery are still scarce. Therefore, the aim was to assess survival, functional status, and trajectory of HRQOL 10 years after cardiac surgery. METHODS: In a prospective population-based study, 534 patients (23% aged 75 years or older, 67% male) were consecutively included before surgery. Functional status was measured according to self-assigned New York Heart Association (NYHA) classification. HRQOL was measured using the Short-Form Health Survey (SF-36). Questionnaires were given to the patients at baseline and sent by post at 6 and 12 months, and 5 and 10 years after surgery. RESULTS: Three hundred fifty-two patients were eligible after 10 years, 274 responded (77.8%). Total survival at 10 years was 67.8%. Patients aged 75 years or older at surgery had lower survival rates than younger patients (44.6% vs 74.6%, P < .001). Seven of 8 SF-36 subscales were improved at 10 years compared with baseline. Older patients improved less than younger patients and linear mixed models showed that older patients had significantly worse trajectories on 3 of 8 SF-36 subscales. NYHA classification improved from baseline to 10 years also among older patients, with 59% in NYHA class III/IV at baseline compared with 30.3% after 10 years (P < .013). CONCLUSIONS: HRQOL and function improved from before to 10 years after cardiac surgery, also for older patients. These long-term results are of major importance when discussing the use of health care resources and patient-centered clinical decision-making.

Validation of the brief pain inventory in patients six months after cardiac surgery.

The Brief Pain Inventory (BPI) is a questionnaire developed to assess the severity of pain and the impact of pain on daily function. The purpose of the current study was to evaluate the psychometric properties of the BPI for use in patients undergoing cardiac surgery. Between September 2004 and September 2005, 534 patients completed the BPI before surgery and 462 responded six months after surgery. The BPI was validated with respect to construct validity, internal consistency, criterion validity, and responsiveness. To evaluate the criterion validity, the BPI was validated against the bodily pain (BP) scale of the Medical Outcomes Study Short-Form Health Survey (SF-36). The factor analysis resulted in two distinct factors, supporting the validity of the two-factor structure of the original BPI, with high loadings on pain severity and pain interference. Results indicated acceptable internal consistency, with Cronbach's alpha coefficients between 0.84 and 0.94. The association between the BPI and the SF-36 BP dimension supported the criterion validity, with correlation coefficients between 0.47 and 0.65. The pain severity scale and the pain interference scale declined from baseline to follow-up. These results supported the responsiveness of the BPI. The study confirmed that the BPI shows good psychometric properties of reliability, validity, and responsiveness, enabling it to be used to measure pain in patients after cardiac surgery. Validating pain measures for use in this population is an important part of establishing a foundation for future studies on chronic pain after cardiac surgery.

Heparin resistance and increased platelet activation in coronary surgery patients treated with enoxaparin preoperatively.

OBJECTIVE: Patients with unstable coronary disease have changes in the hemostatic system. These patients are often treated with low molecular weight heparin. In patients who are accepted for coronary artery bypass grafting, treatment with low molecular weight heparin is frequently continued until surgery. We hypothesized that in coronary artery bypass grafting, the hypercoagulable state seen in unstable patients persists into the intra- and postoperative phase despite preoperative treatment with low molecular weight heparin. The aim of this study was to explore and describe the perioperative hemostatic process in patients with unstable coronary artery disease undergoing coronary artery bypass grafting. METHODS: Thirty-two patients with unstable coronary disease treated preoperatively with enoxaparin, and 32 stable control patients not treated with enoxaparin, were included. All patients were taking low dose aspirin until the day before surgery. Before cardiopulmonary bypass, all patients were given tranexamic acid as a bolus injection. Blood samples for analysis of platelet counts, international normalized ratio, activated partial thromboplastin time, fibrinogen, protein S, protein C, prothrombin fragment 1 + 2, thrombin-antithrombin complex, antithrombin, plasmin-antiplasmin complex, D-dimer, neutrophil-activating peptide 2, platelet-monocyte complexes, and heparin concentrations were drawn preoperatively, after 30 min on cardiopulmonary bypass, and 30 min, 3 h, and 20 h postoperatively. Heparin was given during cardiopulmonary bypass to maintain an activated clotting time above 480 s. RESULTS: Patients in the enoxaparin group needed more heparin to maintain an activated clotting time above 480 s, and had higher heparin concentrations and lower antithrombin values compared with control patients. Neutrophil-activating peptide 2 concentrations were higher in the enoxaparin group. CONCLUSIONS: Patients treated with enoxaparin before coronary artery bypass grafting showed signs of heparin resistance intraoperatively. Enoxaparin-treated patients also had increased perioperative platelet activation. Reasons for the observed difference in platelet activation remain unclear.

Increased fibrinolysis and platelet activation in elderly patients undergoing coronary bypass surgery.

Reexploration for hemorrhage after cardiac surgery is associated with increased morbidity and mortality. Elderly cardiac surgical patients have an increased risk of excessive bleeding and reexploration. In the present study we investigated the perioperative hemostatic function in elderly patients compared with younger patients undergoing coronary artery bypass grafting. Twenty-five elderly (75 yr and older) and 25 younger (younger than 60 yr) patients were included in the study. Blood samples for the analysis of platelet counts, international normalized ratio, activated partial thromboplastin time, fibrinogen, d-dimer, antithrombin, prothrombin fragment 1 + 2, thrombin-antithrombin complex, plasmin inhibitor, neutrophil-activating peptide 2, and platelet-monocyte complexes were drawn preoperatively, 30 min, and 3 h postoperatively and approximately 20 h postoperatively. Elderly patients had an increased activation of the hemostatic system. In particular, elderly patients showed a more pronounced increase in fibrinolysis and platelet activation postoperatively compared with younger patients.