The Influence of Choice of Surgical Procedure on Long-Term Survival After Cardiac Surgery.

BACKGROUND: There is some interest in long-term survival after various cardiac surgical strategies, including off-pump versus on-pump coronary artery surgery (CAG), mitral valve (MV) repair versus replacement, and aortic valve (AV) bioprosthetic versus mechanical replacement. METHODS: We studied patients older than 49 years of age, recording risk factors and surgical details at the time of surgery. We classified procedures as: MV surgery with or without concurrent grafts or valves; AV surgery with or without concurrent CAG; or isolated CAG. Follow-up was through the state death register and state-wide hospital attendance records. Risk-adjusted survival was estimated using Cox proportional hazards. Observed survival was compared to the expected age- and sex- matched population survival. RESULTS: During a median follow-up of 14.8 years 5,807 of 11,718 patients died. The difference between observed and expected survival varied between 3.4 years for AV surgery and 9.6 years for females undergoing MV surgery. The risk-adjusted mortality hazard rate after off-pump CAG was 0.93 (95% CI 0.8-1.0, p=0.84), MV repair 0.67 (95% CI 0.6-0.8, p<0.0001), MV bioprosthesis 0.82 (95% CI 0.81 (0.6-1.0, p=0.11) and bioprosthetic AV replacement 1.02 (95% CI 0.9-1.2, p=0.82). CONCLUSIONS: Compared to the general population, cardiac surgical patients have a shorter than expected life expectancy. We observed a survival benefit of mitral valve repair over replacement. We did not observe significant survival differences between off-pump and on-pump CAG, nor between bioprosthetic and mechanical replacement.

Diagnostic accuracy of viscoelastic point-of-care identification of hypofibrinogenaemia in cardiac surgical patients: A systematic review.

Hypofibrinogenaemia during cardiac surgery may increase blood loss and bleeding complications. Viscoelastic point-of-care tests provide more rapid diagnosis than laboratory measurement, allowing earlier treatment. However, their diagnostic test accuracy for hypofibrinogenaemia has never been reviewed systematically. We aimed to systematically review their diagnostic test accuracy for the identification of hypofibrinogenaemia during cardiac surgery. Two reviewers assessed relevant articles from seven electronic databases, extracted data from eligible articles and assessed quality. The primary outcomes were sensitivity, specificity and positive and negative predictive values. A total of 576 articles were screened and 81 full texts were assessed, most of which were clinical agreement or outcome studies. Only 10 diagnostic test accuracy studies were identified and only nine were eligible (ROTEMdelta 7; TEG5000 1; TEG6S 1, n = 1820 patients) (ROTEM, TEM International GmbH, Munich, Germany; TEG, Haemonetics, Braintree, MA, USA). None had a low risk of bias. Four ROTEM studies with a fibrinogen threshold less than 1.5-1.6 g/l and FIBTEM threshold A10 less than 7.5-8 mm had point estimates for sensitivity of 0.61-0.88; specificity 0.54-0.94; positive predictive value 0.42-0.70; and negative predictive value 0.74-0.98 (i.e. false positive rate 30%-58%; false negative rate 2%-26%). Two ROTEM studies with higher thresholds for both fibrinogen (<2 g/l) and FIBTEM A10 (<9.5 mm) had similar false positive rates (25%-46%), as did the two TEG studies (15%-48%). This review demonstrates that there have been few diagnostic test accuracy studies of viscoelastic point-of-care identification of hypofibrinogenaemia in cardiac surgical patients. The studies performed so far report false positive rates of up to 58%, but low false negative rates. Further diagnostic test accuracy studies of viscoelastic point-of-care identification of hypofibrinogenaemia are required to guide their better use during cardiac surgery.

New antithrombotic agents in the ambulatory setting.

PURPOSE OF REVIEW: Many patients presenting for surgical or other procedures in an ambulatory setting are taking new antiplatelet or anticoagulant agents. This review assesses how the novel features of these new agents affect the management of antithrombotic therapy in the ambulatory setting. RECENT FINDINGS: There have been very few studies investigating the relative risks of continuing or ceasing new antithrombotic agents. Recent reviews indicate that the new antithrombotic agents offer greater efficacy or ease of administration but are more difficult to monitor or reverse. They emphasize the importance of assessing the bleeding risk of the procedure, the thrombotic risk if the agent is ceased, and patient factors that increase the likelihood of bleeding. The timing of cessation of the agent, if required, depends on its pharmacokinetics and patients' bleeding risks. Patients at high risk of thrombotic complications may require bridging therapy. Once agreed upon, the perioperative plan should be made clear to all involved. SUMMARY: As there are few clinical studies to guide management, clinicians must make rational decisions in relation to continuing or ceasing new antithrombotic agents. This requires knowledge of their pharmacokinetics, and a careful multidisciplinary assessment of the relative thrombotic and bleeding risks in individual patients.

Minimally invasive mitral valve surgery using single dose antegrade Custodiol cardioplegia.

OBJECTIVE: Our unit began a minimally invasive mitral surgery (MIMS) program utilising antegrade Custodiol solution as the sole cardioplegia. The aim of this paper is to report our results of this program. PATIENTS/METHODS: Early clinical outcomes were identified and assessed for the first consecutive 100 MIMS patients with comparisons made to a historical group operated via a sternotomy (n=113). The efficacy of myocardial protection was assessed using surrogate outcomes of myocardial protection with serial sodium concentrations also analysed. RESULTS: Six hours postoperatively 12 patients required inotropic support. Peak troponin-I in the first 24 hours was 5.1 (0.8-40 µg/L [median(range)]. Sodium levels decreased following administration of Custodiol but by six hours postoperatively the sodium had returned to greater than 130 mmol/L in all but five patients. Blood transfusion was smaller in the MIMS versus historical group (RBC 17% vs. 65%). MIMS patients had a shorter duration of ventilation, hospital stay and one-year mortality rate (0%). CONCLUSIONS: In this series of patients undergoing MIMS, single dose antegrade Custodiol offers satisfactory and safe myocardial protection. Early clinical outcomes were also satisfactory. Whilst our findings are observational, they nevertheless support the use of this less invasive approach to mitral surgery using single dose Custodiol for myocardial protection.

CT pulmonary angiography during veno-arterial extracorporeal membrane oxygenation in an adult.

Veno-arterial extracorporeal membrane oxygenation (VA ECMO) causes changes in the filling and blood flow of the cardiac chambers and pulmonary vessels as well as alterations in the path of intravenous contrast injected during CT. We present a patient with a potentially misleading CT pulmonary angiogram while on full VA ECMO. We demonstrate circulatory changes as well as alterations in contrast flow when ECMO flows are reduced.

Management of coagulation: an Australian perspective.

PURPOSE OF REVIEW: New anticoagulants and new techniques bring challenges and opportunities to the practice of anaesthesia. Existing guidelines may not be up-to-date with these changes, so this review will examine the current research with a view to identifying deficiencies in existing guidelines, particularly those that may guide Australian anaesthetists. RECENT FINDINGS: The novel oral anticoagulants dabigatran and rivaroxaban, and the potent antiplatelet agents ticagrelor and prasugrel are available in Australia. Considerable research data support the benefit of using these drugs, but the risk profile is incompletely understood. The concept of damage control resuscitation is supported by plentiful, but potentially flawed, observational data, and also the technique may be associated with adverse effects. It remains difficult to firmly quantify the risks of using tranexamic acid or recombinant factor 7a in many clinical situations. SUMMARY: Despite much interesting recent research, few current guidelines are likely to require modification. Novel pharmaceuticals have risk profiles that are incompletely understood, but will only become evident on phase-4 testing. Australasian guidelines for reversal of warfarin may need to be updated to include advice on the use of recombinant factor 7a.

Patient perceptions of regional anesthesia: influence of gender, recent anesthesia experience, and perioperative concerns.

BACKGROUND AND OBJECTIVES: Anesthesiologists often find that patients would prefer a general anesthetic (GA) to a regional anesthetic (RA) for surgery. We surveyed patients' attitudes to RA in an Australian tertiary-care hospital, hoping to understand the reasons for acceptance or refusal. We explored how 3 main factors influence the patient's choice for subsequent RA: gender, type of anesthetic on the day of surgery, and perioperative concerns. METHODS: Consecutive patients at a single institution were interviewed on the first postoperative day by a research nurse, either as a face-to-face interview or by telephone after ambulatory surgery. A short description of RA and GA was given, and preferences for future anesthesia and concerns were recorded. RESULTS: Complete data were obtained from 1000 patients. More women preferred GA compared with men (76.3% vs 69.0%). Patients who received only RA during their surgery on the previous day were almost 3 times more likely to express a future preference for RA compared with those who received any GA, using hypothetical examples of arm or hip surgery (83.2% vs 21.1%, P = 0.00001). Patients expressed more concerns about hearing or seeing the surgery than experiencing a complication, and 84% preferred sedation. CONCLUSIONS: More patients, especially females, may accept RA if reassured appropriately about not hearing or seeing the surgery. Once patients have experienced RA, they are more likely to choose it in future. Modification of our discussion and consent process may increase the uptake of RA techniques.

Moderate exposure to allogeneic blood products is not associated with reduced long-term survival after surgery for coronary artery disease.

BACKGROUND: It has been suggested that blood transfusion has an adverse effect on long-term health, mainly through immune modulation and tumor promotion. To further assess this concern, the authors have performed a prospective observational study with the hypothesis that after taking perioperative risk factors relevant to long-term survival into account, patients undergoing coronary artery surgery who receive a perioperative allogeneic blood transfusion have worse long-term survival than those who do not. METHODS: The health outcomes of 1,841 consecutive subjects who had isolated nonemergency first-time coronary artery surgery and who survived more than 60 days after surgery were determined by record linkage. The association between length of survival, blood products transfused, and risk factors for long-term survival at entry to the study were determined by Cox proportional hazards regression. RESULTS: A total of 1,062 subjects were transfused. Of these, 266 subjects died during a mean follow-up of 8.1 yr. Of subjects who were transfused, 27% had a new malignant condition recorded on the death certificate, compared with 43% who were not transfused. Older age, cerebrovascular disease, use of a mammary graft, chronic pulmonary disease, renal dysfunction, reduced left ventricular function, and preoperative anemia were predictive of reduced long-term survival. There was no association between transfusion of blood products and long-term survival. CONCLUSIONS: Patients who have undergone coronary artery surgery and who have received moderate amounts of blood as part of responsible and conservative management should be reassured that they are unlikely to experience a reduction in long-term survival.

Sternotomy and the beard.

The presence of a beard or lower facial hair can pose a problem during skin preparation, cervical venous line insertion and draping of a patient for a sternotomy. We demonstrate how this can be dealt within a simple and economic fashion.

Transesophageal echocardiography-related gastrointestinal complications in cardiac surgical patients.

OBJECTIVE: The aim of this audit was to determine the incidence of major gastrointestinal (GI) complications associated with intraoperative transesophageal echocardiography (TEE) in adult cardiac surgical patients in this institution. DESIGN: Retrospective database audit. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Eight hundred fifty-nine consecutive cardiac surgical patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The records of all patients who developed a major upper GI complication within 30 days of cardiac surgery between January 2001 and May 2003 were examined. The patients were identified by cross-referencing cardiac surgery and endoscopy databases. A major GI complication was defined as a perforation of the esophagus or stomach or upper GI bleeding requiring transfusion, endoscopic, or surgical intervention. Early presentation was defined as <24 hours; late presentation was defined as >24 hours. During the audit period, 859 patients underwent cardiac surgery. Five hundred sixteen patients had cardiac surgery with TEE (group 1), and 343 patients had cardiac surgery without TEE (group 2). Six patients were identified, 1.2% (95% confidence interval [CI], CI, 0.5%-2.5%) in group 1 who had a major upper GI complication consistent with TEE injury. Two patients, 0.38% (95% CI, 0.05%-1.40%), presented early, and 4 patients, 0.76% (95% CI, 0.21%-1.98%), presented late. One patient in group 2 developed a major upper GI complication, 0.29% (95% CI, 0.01%-1.6%). CONCLUSION: The incidence of major GI complications attributed to TEE in this group of cardiac surgical patients was higher than previously reported. Late presentation was more common than early presentation. Previous studies that have not included late presentations may have underestimated the true incidence of major GI complications related to TEE.

A comparison of Plateletworks and platelet aggregometry for the assessment of aspirin-related platelet dysfunction in cardiac surgical patients.

OBJECTIVE: To compare the assessment of aspirin-related platelet dysfunction using Plateletworks (Helena Laboratories, Beaumont, TX), a new point-of-care platelet function analyzer, with turbidometric platelet aggregometry, in cardiac surgical patients. DESIGN: Prospective observational study. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Fifty consecutive adult patients undergoing elective cardiac surgery for coronary artery bypass grafting or cardiac valve replacement. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Platelet function was assessed by Plateletworks and turbidometric platelet aggregometry before the commencement of anesthesia. Collagen, 10 microg/mL, was used as the agonist for both techniques. The area under the receiver-operator curve for the identification of recent aspirin ingestion (or=72 hours) using Plateletworks was 0.58 (95% confidence interval [CI] 0.42-0.75) versus 0.77 (95% CI 0.61-0.95) for turbidometric platelet aggregometry. The Spearman correlation coefficient (rho) between preoperative Plateletworks trade mark and postoperative mediastinal blood loss was 0.07 (p = 0.58), and between preoperative turbidometric platelet aggregometry and postoperative mediastinal blood loss was -0.31 (p = 0.03). On completion of surgery, the correlation coefficients were 0.14 (p = 0.34) and -0.29 (p = 0.08), respectively. CONCLUSION: These findings suggest that Plateletworks is of limited use for the detection of aspirin-related platelet defects in cardiac surgical patients.

The effect of preoperative aspirin-free interval on red blood cell transfusion requirements in cardiac surgical patients.

OBJECTIVE: To compare red blood cell transfusion in first-time coronary artery surgery patients who stopped taking aspirin < or = 2 days, 3 to 7 days, or >7 days preoperatively. DESIGN: Observational study. SETTING: University-affiliated teaching hospital. PARTICIPANTS: Adult patients (n = 797) undergoing first-time coronary artery surgery on cardiopulmonary bypass who were not receiving other anticoagulant or antiplatelet drugs before surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were divided into 4 groups based on days since last ingestion of aspirin. Blood products transfused in the groups were (aspirin < or =2 days) (n = 140) 2.2 +/- 4 U of red cell concentrate (RCC) (mean +/- SD), 1.4 +/- 3 U of fresh frozen plasma (FFP), and 2.7 +/- 6 U of platelets; (aspirin 3 to 5 days) (n = 255), 1.5 +/- 2 U of RCC, 0.8 +/- 2 U of FFP, and 1.6 +/- 4 U of platelets; (aspirin 6 to 7 days) (n = 215), 1.6 +/- 3 U of RCC, 0.9 +/- 3 U of FFP, and 1.5 +/- 3 U of platelets; and (aspirin >7 days) (n = 187), 1.3 +/- 2 U of RCC; 0.6 +/- 2 U of FFP, and 0.9 +/- 2 U of platelets. CONCLUSION: Patients who stop taking aspirin < or =2 s preoperatively have increased allogenic red blood cell transfusion requirements perioperatively. Patients who stop taking aspirin 3 to 7 days preoperatively have little or no increased requirement for allogenic red blood cell transfusion.