Eshan L. Senanayake

The new EuroSCORE II does not improve prediction of mortality in high-risk patients undergoing cardiac surgery: A collaborative analysis of two European centres

OBJECTIVES Prediction of operative risk in adult patients undergoing cardiac surgery remains a challenge, particularly in high-risk patients. In Europe, the EuroSCORE is the most commonly used risk-prediction model, but is no longer accurately calibrated to be used in contemporary practice. The new EuroSCORE II was recently published in an attempt to improve risk prediction. We sought to assess the predictive value of EuroSCORE II compared with the original EuroSCOREs in high-risk patients. METHODS Patients who underwent surgery between 1 April 2006 and 31 March 2011 with a preoperative logistic EuroSCORE ≥ 10 were identified from prospective cardiac surgical databases at two European institutions. Additional variables included in EuroSCORE II, but not in the original EuroSCORE, were retrospectively collected through patient chart review. The C-statistic to predict in-hospital mortality was calculated for the additive EuroSCORE, logistic EuroSCORE and EuroSCORE II models. The Hosmer-Lemeshow test was used to assess model calibration by comparing observed and expected mortality in a number of risk strata. The fit of EuroSCORE II was compared with the original EuroSCOREs using Akaikes Information Criterion (AIC). RESULTS A total of 933 patients were identified; the median additive EuroSCORE was 10 (interquartile range [IQR] 9-11), median logistic EuroSCORE 15.3 (IQR 12.0-24.1) and median EuroSCORE II 9.3 (5.8-15.6). There were 90 (9.7%) in-hospital deaths. None of the EuroSCORE models performed well with a C-statistic of 0.67 for the additive EuroSCORE and EuroSCORE II, and 0.66 for the logistic EuroSCORE. Model calibration was poor for the EuroSCORE II (chi-square 16.5; P = 0.035). Both the additive EuroSCORE and logistic EuroSCORE had a numerically better model fit, the additive EuroSCORE statistically significantly so (difference in AIC was -5.66; P = 0.017). CONCLUSIONS The new EuroSCORE II does not improve risk prediction in high-risk patients undergoing adult cardiac surgery when compared with original additive and logistic EuroSCOREs. The key problem of risk stratification in high-risk patients has not been addressed by this new model. Future iterations of the score should explore more advanced statistical methods and focus on developing procedure-specific algorithms. Moreover, models that predict complications in addition to mortality may prove to be of increasing value.

Putting the record straight on aprotinin as safe and effective: results from a mixed treatment meta-analysis of trials of aprotinin.

OBJECTIVE Meta-analysis of small, randomized, placebo-controlled trials demonstrated efficacy and safety of aprotinin. After highly publicized retrospective studies and the early stopping of the Blood Conservation Using Antifibrinolytics in a Randomized Trial (BART), aprotinin was withdrawn. We conducted a new meta-analysis (including BART) on safety and efficacy of aprotinin in cardiac surgery. METHODS We conducted a mixed treatment comparisons network meta-analysis estimating the effects of aprotinin and alternative agents in reducing blood loss during surgery. We implemented a combination of direct and indirect evidence in mixed treatment comparisons and estimated relative effects for different agents on all-cause mortality and return to the operating room for bleeding and conducted a supportive analysis of the effects of different agents with only directly randomized trials. RESULTS Mixed treatment analysis of 88 trials randomizing 15,528 patients to 1 of 3 antifibrinolytic agents demonstrated no difference in mortality between placebo and antifibrinolytic agents. Analysis of aprotinin versus tranexamic acid and ε-aminocaproic acid in 17 and 6 trials, respectively and tranexamic acid versus ε-aminocaproic acid in 5 trials demonstrated no difference in mortality between treatment allocations. All agents were superior to placebo in reducing reexploration for bleeding, with aprotinin numerically superior: aprotinin odds ratio, 2.6 (95% confidence interval, 1.9-3.7); tranexamic acid odds ratio, 1.79 (1.2-2.9), and ε-aminocaproic acid odds ratio, 2.4 (1.3-6.6). CONCLUSIONS This mixed treatment comparisons meta-analysis demonstrates no increased mortality risk with aprotinin versus other antifibrinolytic agents. All agents were superior to placebo in reducing reexploration for bleeding after adult cardiac surgery.

Multicentre double-blind randomized controlled trial of perhexiline as a metabolic modulator to augment myocardial protection in patients with left ventricular hypertrophy undergoing cardiac surgery.

OBJECTIVES Patients undergoing cardiac surgery require adequate myocardial protection. Manipulating myocardial metabolism may improve the extent of myocardial protection. Perhexiline has been shown to be an effective anti-anginal agent due to its metabolic modulation properties by inhibiting the uptake of free fatty acids into the mitochondrion, and thereby promoting a more efficient carbohydrate-driven myocardial metabolism. Metabolic modulation may augment myocardial protection, particularly in patients with left ventricular hypertrophy (LVH) known to have a deranged metabolic state and are at risk of poor postoperative outcomes. This study aimed to evaluate the role of perhexiline as an adjunct in myocardial protection in patients with LVH secondary to aortic stenosis (AS), undergoing an aortic valve replacement (AVR). METHODS In a multicentre double-blind randomized controlled trial of patients with AS undergoing AVR ± coronary artery bypass graft surgery, patients were randomized to preoperative oral therapy with either perhexiline or placebo. The primary end point was incidence of inotrope use to improve haemodynamic performance due to a low cardiac output state during the first 6 h of reperfusion, judged by a blinded end points committee. Secondary outcome measures included haemodynamic measurements, electrocardiographic and biochemical markers of new myocardial injury and clinical safety outcome measures. RESULTS The trial was halted early on the advice of the Data Safety and Monitoring Board. Sixty-two patients were randomized to perhexiline and 65 to placebo. Of these, 112 (54 perhexiline and 48 placebo) patients received the intervention, remained in the trial at the time of the operation and were analysed. Of 110 patients who achieved the primary end point, 30 patients (16 perhexiline and 14 placebo) had inotropes started appropriately; there was no difference in the incidence of inotrope usage OR of 1.65 [confidence interval (CI): 0.67-4.06] P = 0.28. There was no difference in myocardial injury as evidenced by electrocardiogram odds ratio (OR) of 0.36 (CI: 0.07-1.97) P = 0.24 or postoperative troponin release. Gross secondary outcome measures were comparable between the groups. CONCLUSIONS Perhexiline as a metabolic modulator to enhance standard myocardial protection does not provide an additional benefit in haemodynamic performance or attenuate myocardial injury in the hypertrophied heart secondary to AS. The role of perhexiline in cardiac surgery is limited.

UK specialist cardiothoracic management of thoracic injuries in military casualties sustained in the wars in Iraq and Afghanistan

OBJECTIVES Outcomes of casualties with thoracic wounding at the deployed UK military field hospital (Role 3(R3)) have been previously described. The level of cardiothoracic specialist input required on repatriation to the UK is less clear. This study aimed to assess the outcomes of casualties with thoracic injuries repatriated to the UK (Role 4 (R4)) and evaluate the impact of specialist cardiothoracic care. METHODS Casualties were identified through the UK Joint Theatre Trauma Registry. Casualties coded for pulmonary contusions and/or thoracotomy between March 2006 and March 2011 were identified and case-notes reviewed. Subgroup analysis was performed for patients with a documented thoracic abbreviated injury score ≥3. RESULTS One hundred and eighty-two UK patients were admitted to UK R4 coded to have a thoracic injury; overall mortality 4.9%. Ninety-three were classified as a thoracic AIS of ≥3; mortality 6.5%. Sixty-four were coded for pulmonary contusions and/or thoracotomy; mortality 1.6, and 66% had thoracic AIS ≥3. Improvised explosive devices injured 54 and 62% had a penetrating injury. Pulmonary contusions were present in 70%; 43% developed a chest infection. Thoracotomy/sternotomy was performed in 13 casualties in R3; 3 re-explored in R4. Oscillatory ventilation and extracorporeal membrane oxygenation was required in 1 case. Cardiothoracic surgery was involved in managing 39% (n = 24) of cases; 11 (45%) required surgical intervention and 19 (79%) had cardiothoracic outpatient follow-up. CONCLUSION Morbidity and mortality associated with significant thoracic injury is low at UK R4. Follow-up is required to assess long-term outcomes. Specialist cardiothoracic support and intervention was required in the management of complex thoracic trauma. Early specialist support at R4 may improve morbidity and outcomes associated with life-threatening thoracic injury.

Stab to the Chest Causing Severe Great Vessel Injury

Penetrating trauma has increased in developed and urban environments. Pulmonary artery injury is rare, but can be associated with significant morbidity. We report a case of delayed cardiac arrest following a stab injury to the chest. The patient had active great vessel bleeding and required extensive surgical intervention. Clinicians should have a high index of suspicion for life-threatening thoracic injuries following a stab injury to the chest, despite initial clinical stability or negative baseline radiological findings.

Chest drains – An overview:

Chest drains are used in a number of circumstances for the treatment of specific conditions and also for symptomatic relief, and hence insertion of a chest drain can be a life-saving intervention. Therefore, it is imperative that every hospital doctor is familiar with the indications and the principles of safe chest drain insertion. The knowledge of chest drain management following insertion is equally essential. Appropriate chest drain insertion and management underpins the management of chest trauma. Appropriate chest drain management will allow for resolution and management of the underlying clinical condition. This review article outlines the indications, contraindications, and principles of chest drain insertion. Furthermore, it provides an overview of chest drain management and associated complications. Although this review refers to a surgically placed chest drain, the same principles can be applied to a chest drain that is inserted percutaneously.

Migration of contraceptive implant into the left pulmonary arterial system

An 18-year-old woman had an etonogestrel implant inserted into her left upper arm 2 years earlier for menorrhagia. Her symptoms were not well controlled and she requested the implant to be removed. However, clinicians were unable to locate the implant on her left arm. Computed tomography showed that the implant had migrated to a sub-lobar branch of the left lower lobe pulmonary artery. The long-term effect of leaving an etonogestrel implant in the pulmonary arterial system is unknown. This report adds to the small body of evidence on intravascular migration of a subdermally placed contraceptive implant.

Clinical outcomes of Carbomedics Top Hat valve with a robust follow-up system.

Aim Late failure of bioprosthetic valves may limit their use in patients < 60 years. The superior hemodynamic performance offered by the Carbomedics Top Hat supraannular valve enables greater effective orifice areas to be achieved. The aim of this study was to assess the clinical outcomes of this valve, using a robust follow-up system. Methods Patients who underwent aortic valve replacement with or without coronary artery bypass grafting between July 1997 and January 2010 with Carbomedics supraannular Top Hat valves were identified. Details of readmissions and late deaths were obtained from the National Hospital Episodes Statistics data and the Office of National Statistics, tracked by the Quality and Outcomes Research Unit. Late complications associated with this prosthesis were evaluated. Results Of 253 patients identified, 181 underwent isolated aortic valve replacement and 72 had aortic valve replacement with coronary artery bypass grafting. The 30-day mortality was 1.6%, and 5- and 10-year survival rates were 91.4% and 80.5%, respectively. Detailed readmission data were available after 2001 (n = 170). Two (1.2%) patients required reoperation for endocarditis and pannus formation. Of the 17 late deaths in this subset, 4 were attributable to cardiac causes. One patient was treated for heart failure, and 2 developed bleeding complications. Conclusions Implantation of the Carbomedics Top Hat supraannular valve in our unit resulted in satisfactory in-hospital and midterm survival with low incidences of endocarditis and late heart failure.

A perilous course following myocardial infarction: ischaemic ventricular septal defect in a transplanted heart

Coronary artery disease in the donor heart is an established cause of early graft failure. However, identification of this before implantation is difficult. Cardiogenic shock associated with significant myocardial infarction during the early postoperative period is rare. Here, we report a case of a 42-year-old man who presented acutely with cardiogenic shock; he was supported by short-term extracorporeal support as a bridge to transplantation. Following successful orthotopic heart transplantation, he sustained coronary artery atheromatous plaque rupture, resulting in acute coronary artery occlusion, and subsequently developed an ischaemic ventricular septal defect on the third postoperative day.