Objective method to evaluate the competency of residents in cardiac surgery.

OBJECTIVES: Cardiac surgery training has become more challenging as patients and their diagnoses become more complex. Our goal was to develop a multicategorical assessment model for evaluating residents in cardiac surgery. This model is intended to ensure goal-directed progress in their training as well as to recognize and support their surgical talents. METHODS: We developed a new questionnaire in a multistage, 3-round process based on the Delphi method 'estimate-talk-estimate', using 55 competencies, including 38 general and 17 domain-specific competencies. Each competency is evaluated with 1 or more questions, to which 1 (not competent) to 6 (very competent) points can be chosen as an answer. RESULTS: The resulting model achieved 2 main goals: first, presenting a well-defined competency list for cardiac surgical training and second, providing an objective and realistic evaluation of trainees' abilities. Residents were assessed by all trainers to achieve a high level of objectivity. CONCLUSIONS: This evaluation model is highly objective, because residents are evaluated by multiple trainers. It allows individual support and enables better transparency in residency training. Talents and skills are evaluated, recognized and adopted as a base for individual feedback and personalized training programmes.

Early Degeneration Caused by Cusp Tear of First-Generation Trifecta Bioprosthesis.

The Trifecta aortic valve has excellent hemodynamic performance as result of an expansive valve design with a bovine pericardial sheet externally mounted on a titanium stent. We report 2 cases of early Trifecta valve degeneration, both caused by partial rupture of one of the leaflet cusps 3 and 4 years post-implant. Post discharge, both patients had routinely performed echocardiography check-ups, without signs of valve failure. Transesophageal echocardiography performed during emergency hospital readmission due to severe dyspnea revealed transvalvular aortic regurgitation without signs of endocarditis. Urgent redo-surgery was successful in both cases, replacing the Trifecta prosthesis with a different bovine bioprosthesis.

Glasgow Coma Scale for outcome prediction after cardiac surgery: is it applicable?

OBJECTIVES: The Glasgow Coma Scale (GCS) is used commonly for assessing patients' neurologic condition and outcome in intensive care units (ICUs); however, its reliability in cardiac surgical patients has been questioned. It has been claimed that active sedation is the cause of its unsuitability for these patients. This study aimed to compare the accuracy of GCS in cardiac surgical patients with and without active sedation to find out if the inapplicability of GCS in surgical patients is related to active sedation. DESIGN: This was an observational cohort study. SETTING: The study was conducted in a cardiac surgical intensive care unit between January 1, 2007 and December 31, 2009. PARTICIPANTS: All consecutive adult cardiac surgical patients were included in this study. INTERVENTIONS: All types of cardiac surgical procedures performed during the study period were included without any exceptions. The study population was divided into 2 groups: sedated and non-sedated. MEASUREMENTS AND MAIN RESULTS: GCS was calculated daily for the first 7 postoperative days. The authors developed a new 4-point neurologic descriptor (ND): (1) neurologically free, (2) ICU psychosis, (3) actively sedated, and (4) documented focal neurologic deficits. The accuracy of both scales (GCS and ND) at predicting ICU mortality was compared by replacing the GCS in the Sequential Organ Failure Assessment (SOFA) score with the new ND, producing a modified SOFA. GCS was not an accurate outcome predictor in non-sedated or sedated patients. The ND was superior to GCS. Correspondingly, the modified SOFA showed a significantly higher accuracy of ICU-mortality prediction than the original SOFA. CONCLUSIONS: Regardless of active sedation, GCS is not accurate at outcome prediction for cardiac surgical patients. The suggested ND is a simple and more accurate risk stratification variable in cardiac surgical ICUs.

SAPS 3 is not superior to SAPS 2 in cardiac surgery patients.

OBJECTIVES: Cardiac surgery patients are excluded from SAPS2 but included in SAPS3. Neither score is evaluated for this exclusive population; however, they are used daily. We hypothesized that SAPS3 may be superior to SAPS2 in outcome prediction in cardiac surgery patients. DESIGN: All consecutive patients undergoing cardiac surgery between January 2007 and December 2010 were included in our prospective study. Both models were tested with calibration and discrimination statistics. We compared the AUC of the ROC curves by DeLong's method and calculated OCC values. RESULTS: A total of 5207 patients with mean age of 67.2 ± 10.9 years were admitted to the ICU. The mean length of ICU stay was 4.6 ± 7.0 days and the ICU mortality was 5.9%. The two tested models had acceptable discriminatory power (AUC: SAPS2: 0.777-0.875; SAPS3: 0.757-893). SAPS3 had a low AUC and poor calibration on admission day. SAPS2 had poor calibration on Days 1-6 and 8. CONCLUSIONS: Despite including cardiac surgery patients, SAPS3 was not superior to SAPS2 in our analysis. In this large cohort of ICU cardiac surgery patients, performance of both SAPS models was generally poor. In this subset of patients, neither scoring system is recommended.

Mortality prediction after cardiac surgery: blood lactate is indispensible.

BACKGROUND: Blood lactate is accepted as a mortality risk marker in intensive care units (ICUs), especially after cardiac surgery. Unfortunately, most of the commonly used ICU risk stratification scoring systems did not include blood lactate as a variable. We hypothesized that blood lactate alone can predict the risk of mortality after cardiac surgery with an accuracy that is comparable to those of other complex models. We therefore evaluated its accuracy at mortality prediction and compared it with that of other widely used complex scoring models statistically. METHODS: We prospectively collected data of all consecutive adult patients who underwent cardiac surgery between January 1, 2007, and December 31, 2009. By using χ2 statistics, a blood lactate-based scale (LacScale) with only four cutoff points was constructed in a developmental set of patients (January 1, 2007, and May 31, 2008). LacScale included five categories: 0 (≤ 1.7 mmol/L); 1 (1.8-5.9 mmol/L), 2 (6.0-9.3 mmol/L), 3 (9.4-13.3 mmol/L), and 4 (≥ 13.4 mmol/L). Its accuracy at predicting ICU mortality was evaluated in another independent subset of patients (validation set, June 1, 2008, and December 31, 2009) on both study-population level (calibration analysis, overall correct classification) and individual-patient-risk level (discrimination analysis, ROC statistics). The results were then compared with those obtained from other widely used postoperative models in cardiac surgical ICUs (Sequential Organ Failure Assessment [SOFA] score, Simplified Acute Physiology Score II [SAPS II], and Acute Physiology and Chronic Health Evaluation II [APACHE II] score). RESULTS: ICU mortality was 5.8% in 4,054 patients. LacScale had a reliable calibration in the validation set (2,087 patients). It was highly accurate in predicting ICU mortality with an area under the ROC curve (area under curve [AUC]; discrimination) of 0.88. This AUC was significantly larger than that of all the other models (SOFA 0.83, SAPS II: 0.79 and APACHE II: 0.76) according to DeLong's comparison. Integrating the LacScale in those scores further improved their accuracy by increasing their AUCs (0.88, 0.81, and 0.80, respectively). This improvement was also highly significant. CONCLUSION: Blood lactate accurately predicts mortality at both individual patient risk and patient cohort levels. Its precision is higher than that of other commonly used "complex" scoring models. The proposed LacScale is a simple and highly reliable model. It can be used (at bedside without electronic calculation) as such or integrated in other models to increase their accuracy.

Rapid clinical evaluation: an early warning cardiac surgical scoring system for hand-held digital devices.

OBJECTIVES: The purpose of this study was to develop a new scoring system for the prompt recognition of clinical deterioration and early treatment in postoperative cardiac surgical patients. METHODS: All consecutive adult patients undergoing cardiac surgery between 1st January 2007 and 31st December 2010 were included. The new score was calculated daily until intensive care unit (ICU) discharge. The score consists of 11 variables representing six different organ systems. Performance was assessed using receiver-operating characteristic (ROC) curves and calibration tests. RESULTS: A total of 5207 patients with a mean age of 67.2 ± 10.9 years were admitted to the ICU after cardiac surgery. The operations performed covered the whole spectrum of cardiac surgery. ICU mortality was 5.9%. The mean length of ICU stay was 4.6 ± 7.0 days. The new score had an excellent discrimination with areas under the ROC curves between 0.91 and 0.96. Calibration was also excellent reflected by observed/expected mortality ratios ranging between 1.0 and 1.26. CONCLUSIONS: The new score is a simple and reliable scoring system to assess organ dysfunction in cardiac intensive care patients. It is designed especially for personal digital assistants to simplify and accelerate the process of risk stratification in cardiac surgical ICUs.

Preoperative risk stratification models fail to predict hospital cost of cardiac surgery patients.

BACKGROUND: Preoperative risk stratification models have previously been suggested to predict cardiac surgery unit costs. However, there is a lack of consistency in their reliability in this field. In this study we aim to test the correlation between the values of six commonly known preoperative scoring systems and evaluate their reliability at predicting unit costs of cardiac surgery patients. METHODS: Over a period of 14 months all consecutive adult patients undergoing cardiac surgery on cardiopulmonary bypass were prospectively classified using six preoperative scoring models (EuroSCORE, Parsonnet, Ontario, French, Pons and CABDEAL). Transplantation patients were the only patients we excluded. Total hospital costs for each patient were calculated independently on a daily basis using the bottom up method. The full unit costs were calculated including preoperative diagnostic tests, operating room cost, disposable materials, drugs, blood components as well as costs for personnel and fixed hospital costs. The correlation between hospital cost and the six models was determined by linear regression analysis. Both Spearman's and Pearson's correlation coefficients were calculated from the regression lines. An analysis of residuals was performed to determine the quality of the regression. RESULTS: A total of 887 patients were operated on for CABG (n = 608), valve (n = 142), CABG plus valve (n = 100), thoracic aorta (n = 33) and ventricular assist devices (n = 4). Mean age of the patients was 68.3±9.9 years, 27.6% were female. 30-day mortality rate was 4.1%. Correlation between the six models and hospital cost was weak (Pearson's: r < 0.30; Spearman's: r < 0.40). CONCLUSION: The risk stratification models in this study are not reliable at predicting total costs of cardiac surgical patients. We therefore do not recommend their use for this purpose.

Successful management of a massive residual space empyema using intrathoracic vacuum-assisted instillation.

There is no universally accepted single line treatment for residual space empyema. Recently, the vacuum-assisted instillation therapy was applied for wounds in different anatomical positions. However, it has not yet been applied as an intrathoracic management. Herein, we describe the first experience of intrathoracic vacuum-assisted instillation therapy for residual space empyema after extended thoracic surgery. It appears to be an attractive treatment option for patients with large contaminated pleural cavities in preparation for reconstructive surgery.

Daily-Mean-SOFA, a new derivative to increase accuracy of mortality prediction in cardiac surgical intensive care units.

BACKGROUND: Sequential organ failure assessment (SOFA) score is widely used in many cardiac surgical intensive care units (ICUs). Its derivatives (mean and maximum values) are known to be more accurate than the original daily values of SOFA itself. However, they were designed for research purposes and could be calculated only after ICU discharge. We aimed to develop a reliable derivative that can be easily calculated daily (Daily-Mean-SOFA) for aiding daily-decision-making and resource allocation. METHODS: All consecutive adult cardiac surgical patients from our ICU between January 1, 2007 and December 31, 2008 were included. We obtained Initial-SOFA (on day 1), the Original-Daily-SOFA value from the 1st to the 6th postoperative day, Max-SOFA (highest SOFA value during the whole ICU-stay), Mean-SOFA (sum of all daily SOFA values/the length of ICU-stay), and the new "Daily-Mean-SOFA" from day 2 to 6 (sum of SOFA from day 1 until day-n/n). We compared their accuracies at predicting ICU mortality using calibration and discrimination statistics. RESULTS: Total 2801 patients were included. The newly developed "Daily-Mean-SOFA" was significantly more accurate than the corresponding SOFA value of the same day in correctly predicting survival and mortality in the whole study population (OCC: 94.1 to 95.0%) and in accurately identifying the individual patient's risk of mortality (AUC: 0.859 to 0.904). It was better than all other derivatives except the Mean-SOFA which was superior to it (OCC: 96.3%; AUC: 0.913). CONCLUSIONS: The Daily-Mean-SOFA is a reliable derivative for daily risk stratification in cardiac ICUs. Due to its accuracy and daily availability, it may be used for risk-directed therapy in cardiac ICUs.

Logistic Organ Dysfunction Score (LODS): a reliable postoperative risk management score also in cardiac surgical patients?

BACKGROUND: The original Logistic Organ Dysfunction Sore (LODS) excluded cardiac surgery patients from its target population, and the suitability of this score in cardiac surgery patients has never been tested. We evaluated the accuracy of the LODS and the usefulness of its daily measurement in cardiac surgery patients. The LODS is not a true logistic scoring system, since it does not use ß-coefficients. METHODS: This prospective study included all consecutive adult patients who were admitted to the intensive care unit (ICU) after cardiac surgery between January 2007 and December 2008. The LODS was calculated daily from the first until the seventh postoperative day. Performance was assessed with Hosmer-Lemeshow (HL) goodness-of-fit test (calibration) and receiver operating characteristic (ROC) curves (discrimination) from ICU admission day until day 7. The outcome measure was ICU mortality. RESULTS: A total of 2801 patients (29.6% female) with a mean age of 66.4 ± 10.7 years were included. The ICU mortality rate was 5.2% (n = 147). The mean stay on the ICU was 4.3 ± 6.8 days. Calibration of the LODS was good with no significant difference between expected and observed mortality rates on any day (p ≥ 0.05). The initial LODS had an area under the ROC curve (AUC) of 0.81. The AUC was best on ICU day 3 with a value of 0.93, and declined to 0.85 on ICU day 7. CONCLUSIONS: Although the LODS has not previously been validated for cardiac surgery patients it showed reasonable accuracy in prediction of ICU mortality in patients after cardiac surgery.

A comparative study of four intensive care outcome prediction models in cardiac surgery patients.

BACKGROUND: Outcome prediction scoring systems are increasingly used in intensive care medicine, but most were not developed for use in cardiac surgery patients. We compared the performance of four intensive care outcome prediction scoring systems (Acute Physiology and Chronic Health Evaluation II [APACHE II], Simplified Acute Physiology Score II [SAPS II], Sequential Organ Failure Assessment [SOFA], and Cardiac Surgery Score [CASUS]) in patients after open heart surgery. METHODS: We prospectively included all consecutive adult patients who underwent open heart surgery and were admitted to the intensive care unit (ICU) between January 1st 2007 and December 31st 2008. Scores were calculated daily from ICU admission until discharge. The outcome measure was ICU mortality. The performance of the four scores was assessed by calibration and discrimination statistics. Derived variables (Mean- and Max- scores) were also evaluated. RESULTS: During the study period, 2801 patients (29.6% female) were included. Mean age was 66.9 ± 10.7 years and the ICU mortality rate was 5.2%. Calibration tests for SOFA and CASUS were reliable throughout (p-value not < 0.05), but there were significant differences between predicted and observed outcome for SAPS II (days 1, 2, 3 and 5) and APACHE II (days 2 and 3). CASUS, and its mean- and maximum-derivatives, discriminated better between survivors and non-survivors than the other scores throughout the study (area under curve ≥ 0.90). In order of best discrimination, CASUS was followed by SOFA, then SAPS II, and finally APACHE II. SAPS II and APACHE II derivatives had discrimination results that were superior to those of the SOFA derivatives. CONCLUSIONS: CASUS and SOFA are reliable ICU mortality risk stratification models for cardiac surgery patients. SAPS II and APACHE II did not perform well in terms of calibration and discrimination statistics.

Prediction of mortality in intensive care unit cardiac surgical patients.

OBJECTIVES: The purpose of this study was to develop a specific postoperative score in intensive care unit (ICU) cardiac surgical patients for the assessment of organ dysfunction and survival. To prove the reliability of the new scoring system, we compared its performance to existing ICU scores. METHODS: This prospective study consisted of all consecutive adult patients admitted after cardiac surgery to our ICU over a period of 5.5 years. Variables were evaluated using the patients of the first year who stayed in ICU for at least 24h. The reproducibility was then tested in two validation sets using all patients. Performance was assessed with the Hosmer-Lemeshow (HL) goodness-of-fit test and receiver operating characteristic (ROC) curves and compared with the Acute Physiology and Chronic Health Evaluation (APACHE II) and Multiple Organ Dysfunction Score (MODS). The outcome measure was defined as 30-day mortality. RESULTS: A total of 6007 patients were admitted to the ICU after cardiac surgery. Mean HL values for the new score were 5.8 (APACHE II, 11.3; MODS, 9.7) for the construction set, 7.2 (APACHE II, 8.0; MODS, 4.5) for the validation set I and 4.9 for the validation set II. The mean area under the ROC curve was 0.91 (APACHE II, 0.86; MODS, 0.84) for the new score in the construction set, 0.88 (APACHE II, 0.84; MODS, 0.84) in the validation set I and 0.92 in the validation set II. CONCLUSIONS: Most of general ICU scoring systems use extensive data collection and focus on the first day of ICU stay. Despite this fact, general scores do not perform well in the prediction of outcome in cardiac surgical patients. Our new 10-variable risk index performs very well, with calibration and discrimination very high, better than general severity systems, and it is an appropriate tool for daily risk stratification in ICU cardiac surgery patients. Thus, it may serve as an expert system for diagnosing organ failure and predicting mortality in ICU cardiac surgical patients.

Third-generation mobile phones (UMTS) do not interfere with permanent implanted pacemakers.

AIMS: Third-generation mobile phones, UMTS (Universal Mobile Telecommunication System), were recently introduced in Europe. The safety of these devices with regard to their interference with implanted pacemakers is as yet unknown and is the point of interest in this study. METHODS AND RESULTS: The study comprised 100 patients with permanent pacemaker implantation between November 2004 and June 2005. Two UMTS cellular phones (T-Mobile, Vodafone) were tested in the standby, dialing, and operating mode with 23 single-chamber and 77 dual-chamber pacemakers. Continuous surface electrocardiograms (ECGs), intracardiac electrograms, and marker channels were recorded when calls were made by a stationary phone to cellular phone. All pacemakers were tested under a "worst-case scenario," which includes a programming of the pacemaker to unipolar sensing and pacing modes and inducing of a maximum sensitivity setting during continuous pacing of the patient. Patients had pacemaker implantation between June 1990 and April 2005. The mean age was 68.4 +/- 15.1 years. Regardless of atrial and ventricular sensitivity settings, both UMTS mobile phones (Nokia 6650 and Motorola A835) did not show any interference with all tested pacemakers. In addition, both cellular phones did not interfere with the marker channels and the intracardiac ECGs of the pacemakers. CONCLUSION: Third-generation mobile phones are safe for patients with permanent pacemakers. This is due to the high-frequency band for this system (1,800-2,200 MHz) and the low power output between 0.01 W and 0.25 W.

Gaseous emboli during off-pump surgery with T-graft technique, two different mechanisms.

OBJECTIVES: Gaseous embolism is a possible complication during off-pump coronary surgery with the use of a blower and can cause ischemic injuries. We describe two different possible mechanisms of carbon-dioxide embolization. METHODS: Out of 2196 coronary bypass surgeries, between 1 January 2007 and 31 December 2009, there were 977 off-pump operations. Two off-pump cases (0.2%) had gaseous (carbon-dioxide) emboli that migrated against blood stream proximally through T-anastomoses and then into the native coronary vessels. These emboli caused a temporary haemodynamic deterioration in other territories. Two types of T-anastomoses were included [saphenous vein on left internal thoracic artery (LITA) or right internal thoracic artery (RITA) on LITA]. RESULTS: Simple procedures and measurements were necessary but enough to regain haemodynamic stability. There was no effect on the postoperative outcome. CONCLUSION: We have concluded that carbon-dioxide emboli can also cause massive but temporary haemodynamic deterioration during off-pump surgery despite higher solubility in blood. The blower should be used only when a bull-dog clamp is applied on the graft. Also, proper de-airing and flushing of grafts is very important and avoids consequences of the trapped small emboli.

Effect of clopidogrel on perioperative blood loss and transfusion in coronary artery bypass graft surgery.

The effect of antiplatelet therapy (APT) on postoperative bleeding, transfusion needs and re-exploration remains unclear. This study examines the influence of APT, as well as antiplatelet mono- and combined therapy, on haemorrhage and transfusion requirements in patients undergoing coronary artery bypass on cardiopulmonary bypass (CPB). Six hundred and fifty patients were reviewed retrospectively, 325 patients received APT within seven days and 325 control patients. APT group had two subgroups: clopidogrel (CLO) group: n=48 patients received CLO as mono-therapy; combined group: n=277 patients received both CLO and aspirin (ASS). The mediastinal drainage at 12 h was control group: 505 ml+/-445 ml and APT group: 802 ml+/-720 ml, P<0.001. APT group (vs. control group) received significantly more units of blood (3.9+/-4.2 vs. 1.9+/-2.6; P<0.001), platelet units (1.0+/-1.4 vs. 0.1+/-0.3; P<0.001), and fresh frozen plasma (FFP) units (2.9+/-3.9 vs. 0.9+/-2.2; P<0.001), respectively. Combined and mono-therapy groups had no significant differences in bleeding and blood transfusion. Considerations should be given to delaying elective coronary surgery for patients received APT for seven days.