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OBJECTIVE: To increase the number of off-pump coronary procedures at our institution, a new surgical team was formed. The first 3 years of "learning period" were accompanied by a quality management program aimed to control and adjust the surgical process and to ensure the safety and quality of the procedure. METHODS: All patients were operated on by the same surgeon between January 2004 and December 2006; all procedures were performed under the following quality management protocol. First, a flow chart regulated surgical and anesthetic details. Second, an online file, named "disturbance file," was used to report work flow interruption, disturbance, and intraoperative events, that is, myocardial ischemia, hypotension, conversion to cardiopulmonary bypass, and any violation of the protocol. Each event was coded with 1 point and added to a score (the higher the score is, the greater the disturbance). Outcome parameters known as major events-major cardiac and cerebral events: mortality within 30 days/myocardial infarction confirmed by electrocardiogram or significantly high levels of total creatine kinase-myocardial muscle creatine kinase/reintervention within 30 days/stroke--and new-onset dialysis were also measured. Success was defined as freedom from any of those events and depicted in a cumulative sum control (CUSUM) chart. Outcome data and CUSUM were correlated with the intraoperative Disturbance Index. RESULTS: In total, 490 off-pump coronary bypass operations were performed by the named surgeon during the study period. The 30-day mortality was reduced from 4.0% to 1.9%. Disturbance Index score of greater than 1 declined from 41.6% to 23.3%. All major cardiac and cerebral events declined. The CUSUM chart showed two critical periods during the learning period, which made an adjustment of the protocol necessary. CONCLUSIONS: Quality management control is efficient in improving the postoperative results of a surgical procedure. A learning period is of cardinal importance for any new team wishing to engage in a novel surgical technique.

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BACKGROUND AND AIM OF THE STUDY: Thrombocytopenia after implantation of the Sorin Freedom Solo (FS) stentless aortic bioprosthesis has been described previously. Thus, relevant data acquired at the authors' institution were analyzed. METHODS: A comparison of platelet counts was made in patients operated on between January and August 2008 following implantation of either the FS valve (n = 26) or a stented pericardial prosthesis (n = 238). Thrombocyte levels were measured before surgery and on days 0, 1, 2, 3, 5 and 7 after surgery; a comparison was made using absolute and hematocrit-adjusted platelet counts. Clinical adverse events were investigated in both groups, and a multivariate analysis was performed to identify predictors for the occurrence of thrombocytopenia. RESULTS: After implantation of the FS valve, the mean absolute and hematocrit-adjusted platelet counts were significantly lower on days 2, 3, 5 and 7 after surgery. An additional decrease occurred between days 1 and 3 after surgery, but this was not associated with any adverse clinical outcome. Independent determinants for thrombocytopenia were age and the type of aortic prosthesis. Postoperative echocardiography revealed lower gradients after FS valve implantation. CONCLUSION: Given the superior hemodynamic performance of the FS valve, and the absence of any adverse effects, implantation with this valve may be justified in selected patients. Further clarification of the mechanisms causing thrombocytopenia is required.

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BACKGROUND AND AIM OF THE STUDY: Although, in small aortic annulus or aortic annulus calcification, it is recommended that valves are implanted in a tilted position, mechanical valves show impaired hemodynamic performance when positioned in this way. To date, no investigations have been conducted with biological valves implanted in a tilted position. METHODS: Measurements were performed in a pulsatile flow simulator. The aortic roots were mounted in a fluid reservoir and tested with bioprosthetic valves implanted in the regular position (21 mm; n = 7) or at a 200 tilt (23 mm; n = 7). Additional 21 mm valves were implanted in both positions with a systemic pressure of 120/80 mmHg. Subsequently, the valves were implanted into a glass model and flow visualization monitored by adding air bubbles illuminated with a laser diode. RESULTS: The 21 mm valves showed a slightly higher transvalvular gradient in the tilted than in the regular position, while 23 mm valves in a tilted position showed a lower gradient than 21 mm valves in the regular position. Flow in the regular position was seen to be straight and central, but in the tilted position was diverted and impacted on the aortic wall. Vortex formation in the tilted position was more pronounced than in the regular position, with certain low-flow areas being observed. CONCLUSION: The implantation of a one size-larger bioprosthetic valve at a 20 degree tilt in a small aortic root resulted in a slight reduction in transvalvular gradient compared to a smaller valve implanted in the regular position. Whilst mechanical valve performance is markedly compromised in the tilted position, the bioprosthetic valve showed only minor impairment of transvalvular pressure gradient due to tilting, and this was overcompensated by the larger valve size. However, the advantage of a greater orifice area must be traded against the consequences of the observed flow disturbances.

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We report the rare case of an air gun pellet retained within the myocardium. The pellet passed through the right ventricle and the interventricular septum and was retained in the posterior left ventricular wall. The patient presented with cardiac tamponade requiring urgent surgical treatment. The case report is followed by a review of the pertinent literature.

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BACKGROUND: Cerebral oxygen saturation (ScO2) can be assessed by near-infrared spectroscopy. We investigated the correlation between early postoperative cognitive performance and intraoperative ScO2 in a prospective observational setting. METHODS: Forty-seven patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass underwent preoperative and postoperative neuropsychological evaluation. Patients were classified according to the presence or absence of postoperative cognitive dysfunction. Cognitive dysfunction was defined as an individual test score decrease of more than one standard deviation in two or more of the five tests. During operation ScO2 was continuously measured using an INVOS 4100 device. Cerebral oxygen saturation values were analyzed with reference to two cutoff points, which should reflect low cerebral oxygenation: an ScO2 less than 40% and a drop of more than 25% from individual baseline values. The duration and extent of ScO2 values below these two cutoff points was compared between the patients with and without cognitive dysfunction. RESULTS: Sixteen patients (34%) showed postoperative cognitive dysfunction. Cerebral oxygen saturation values less than 40% occurred in 17 patients for a mean (+/- standard error of the mean) of 17.2 +/- 6.5 minutes, whereas a decrease of more than 25% from baseline values occurred in 37 patients for 52.7 +/- 7.8 minutes. The duration and extent below the two cutoff ScO2 values was similar in patients with and without cognitive dysfunction. CONCLUSIONS: Intraoperative regional ScO2 as assessed by near-infrared spectroscopy with the INVOS 4100 device is not predictive for postoperative cognitive performance in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.

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