Faculty Bibliography

BACKGROUND:Sternal wound infections are considered a costly and potentially devastating consequence of the median sternotomy in cardiothoracic surgery. Surgical incision management employs the technique of applying a closed, negative pressure vacuum dressing to a closed wound. Several studies have demonstrated a reduction in sternal wound infections using this system. METHODS:A retrospective audit of cases receiving surgical incision management demonstrated a statistically significant reduction in sternal wound infections against a predicted rate. RESULTS:Of the 62 patients identified, only one was complicated by a sternal wound infection with the greatest reduction seen in the high-risk infection group. CONCLUSIONS:Although smaller in size, the results compared well to trials conducted in larger European and US centres. Although not advocating surgical incision management for routine use, it should be considered on patients considered high-risk for sternal wound infection, such as diabetics, the elderly and the obese.

Giant thymic cysts are a rare clinical entity evolving from smaller benign thymic cysts over many years. Benign thymic cysts account for approximately 3% of all mediastinal masses. There is a paucity of literature regarding benign thymic cyst management, especially when dealing with giant cysts. This can lead to potential confusion amongst clinicians on how to best treat these patients. We report the successful diagnosis and treatment of a 76 year-old female with a giant, benign thymic cyst. This cyst was discovered incidentally and after consultation of the literature it was found management strategies regarding this condition are scarce. After careful consideration of surgical principles, patient preference and potential complications of a conservative approach, the successful surgical removal of a 1.8 kg cyst took place. The patient improved symptomatically with improved exercise tolerance and lung function tests. This case demonstrates the benefits of giant thymic cyst removal thus confirming diagnosis, reducing potential serious complications and improving patient quality of life.

OBJECTIVE:The aims of this study were first to analyze neurocognitive outcomes of patients after open-chamber cardiac surgery to determine whether carbon dioxide pericardial insufflation reduces incidence of neurocognitive decline (primary end point) as measured 6 weeks postoperatively and second to assess the utility of carbon dioxide insufflation in cardiac chamber deairing as assessed by transesophageal echocardiography. METHODS:A multicenter, prospective, double-blind, randomized, controlled trial compared neurocognitive outcomes in patients undergoing open-chamber (left-sided) cardiac surgery who were assigned carbon dioxide insufflation or placebo (control group) in addition to standardized mechanical deairing maneuvers. RESULTS:One hundred twenty-five patients underwent surgery and were randomly allocated. Neurocognitive testing showed no clinically significant differences in z scores between preoperative and postoperative testing. Linear regression was used to identify factors associated with neurocognitive decline. Factors most strongly associated with neurocognitive decline were hypercholesterolemia, aortic atheroma grade, and coronary artery disease. There was significantly more intracardiac gas noted on intraoperative transesophageal echocardiography in all cardiac chambers (left atrium, left ventricle, and aorta) at all measured times (after crossclamp removal, during weaning from cardiopulmonary bypass, and at declaration of adequate deairing by the anesthetist) in the control group than in the carbon dioxide group (P < .04). Deairing time was also significantly longer in the control group (12 minutes [interquartile range, 9-18] versus 9 minutes [interquartile range, 7-14 minutes]; P = .002). CONCLUSIONS:Carbon dioxide pericardial insufflation in open-chamber cardiac surgery does not affect postoperative neurocognitive decline. The most important factor is atheromatous vascular disease.

BACKGROUND:Little is known about the outcome of cardiac surgery in patients with a prior history of malignancy. Our aim was to investigate in our unit the population of patients with a known malignancy and compare their outcomes to a matched population without malignancy. METHODS:We identified all patients who underwent cardiac surgery at the Alfred Hospital between February 2002 and December 2009 with malignancy. Cases were matched to 216 controls based on age, gender, major medical comorbidities and type of surgery. A univariate analysis was performed with Fishers exact test and χ(2) test. RESULTS:83/4474 patients were identified with malignancy. Sixty-four (77%) were male. Mean age of the patients with malignancy was 66.7 years, and 67.4 in the control group. 68.7% had a solid organ tumour, and 31.3% had a haematological malignancy. There were no significant between-group differences in hospital or 30-day mortality. However, there were significantly higher rates of transfusion (79.5% vs 49%, p<0.0001), reintubation (8.4% vs 0.9%, p=0.0009), pneumonia (14.5% vs 6%, p=0.035), septicaemia (8.4% vs 1.9%, p=0.018), arrhythmias (42.2% vs. 33.8%, p=0.047) and anticoagulant complications (7.2% vs 0%, p=0.008) in patients with malignancies. CONCLUSION/CONCLUSIONS:Patients who present for cardiac surgery having had prior treatment for cancer are at particular risk for complications. However, these patients can be operated upon with acceptable risk. There is no difference in the short term mortality. Therefore, for selected patients who are undergoing curative treatment for their malignancy, or are in remission, cardiac surgery is not contraindicated.

OBJECTIVE:Aprotinin has been widely used to reduce bleeding and transfusion requirements in cardiac surgery and in lung transplantation. A recent study found a significant reduction in severe (grade III) primary graft dysfunction (PGD) in lung transplantation where aprotinin had been used. However, recently, concerns regarding the safety of aprotinin have been raised, and the future use of aprotinin is uncertain. In our institution, aprotinin has been widely used in cardiac surgery and transplantation. We decided to review our lung transplant caseload to investigate the impact of aprotinin on PGD and mortality and to guide our future clinical use of this antifibrinolytic. METHODS:A retrospective review of prospectively collected data on 213 consecutive patients who underwent single- or double-lung transplantation was performed. Ninety-nine patients, who received aprotinin, were compared with 114 patients who did not. The main outcome variables analysed were development of primary graft dysfunction, renal impairment and mortality. RESULTS:Aprotinin was associated with a significantly increased risk of PGD in the first 48 h postoperatively (p=0.01). CONCLUSIONS:In conclusion, although the benefits of aprotinin on blood loss are well established, this study does not provide support for the use of aprotinin to reduce PGD in lung transplantation and indicates that aprotinin may in fact have a detrimental effect.

BACKGROUND:Our aim was to study the independent effect of heart rate (HR) on parameters of diastolic function, particularly mitral annular velocities measured by tissue Doppler imaging (TDI), an effect which is not well understood. METHODS:Sixteen patients with dual chamber pacemakers attending for routine pacemaker review underwent detailed echocardiographic assessment during atrial pacing with intact atrioventricular conduction at baseline and accelerated HRs. Mitral inflow and annular tissue Doppler velocities and systolic strain parameters were compared. RESULTS:Parameters of systolic function were unaffected by increased HR. When these parameters were compared at baseline (mean 67 bpm) and accelerated HR (mean 80 bpm), the following was observed: a significant decrease in early mitral inflow (E) wave (70.5 +/- 5.5 cm/s vs 63.5 +/- 4.9 cm/s, P < 0.02) and early mitral annular (E') velocities (7.0 +/- 0.5 cm/s vs 6.3 +/- 0.6 cm/s, P < 0.003) and a significant increase in mitral inflow A wave (70.3 +/- 4.5 cm/s vs 77.3 +/- 4.4 cm/s, P < 0.05) and late mitral annular (A') velocities (9.3 +/- 0.6 cm/s vs 10.8 +/- 0.5, P < 0.00004). CONCLUSION/CONCLUSIONS:Changes in HR have previously unrecognized significant effects on tissue Doppler parameters of diastolic function. Further study is required to determine if tissue Doppler derived annular velocities should be corrected for HR.