The practicalities of establishing a porcine isolated heart model.

BACKGROUND: The isolated heart apparatus is over 100 years old, but remains a useful research tool today. While designs of many large animal systems have been described in the literature, trouble-shooting and refining such a model to yield a stable, workable system has not been previously described. This paper outlines the issues, in tabular form, that our group encountered in developing our own porcine isolated heart rig with the aim of assisting other workers in the field planning similar work. The paper also highlights some of the modern applications of the isolated heart apparatus. Methods Landrace pigs (50-80 kg) were used in a pilot project to develop the model. The model was then used in a study examining the effects of various cardioplegic solutions on function after reanimation of porcine hearts. During the two projects, non-protocol issues were documented as well as their solutions. These were aggregated in this paper. RESULTS: Issues faced by the group without explicit literature solutions included pig size selection, animal acclimatisation, porcine transoesophageal echocardiography, cannulation and phlebotomy for cross-clamping, cardioplegia delivery, heart suspension and rig tuning. CONCLUSION: Prior recognition of issues and possible solutions faced by workers establishing a porcine isolated heart system will speed progress towards a useable system for research. The isolated heart apparatus remains applicable in transplant, ischaemia reperfusion, heart failure and organ preservation research.

Penetrating Cardiac Injury Managed Without Surgery but with Systemic Heparinisation.

A 36-year-old woman presented to hospital after a penetrating chest injury. She was haemodynamically stable. Echocardiography revealed left ventricular thrombus, with minimal pericardial effusion and no associated cardiac injuries. Intravenous anticoagulation was commenced for her intracardiac thrombus and her pericardial effusion was monitored with serial echocardiography. She remained well, was converted to warfarin and discharged home day 12 post admission, with cautious follow-up given her risk of late effusion and tamponade. Follow-up imaging revealed resolution of her intracardiac thrombus. She remains well to date.

Extracorporeal-assisted rewarming in the management of accidental deep hypothermic cardiac arrest: a systematic review of the literature.

A systematic review of the literature surrounding the use of Extra-Corporeal Assisted Rewarming (ECAR) in patients presenting with deep hypothermia or hypothermic cardiac arrest was undertaken using a structured protocol. Thirty-one papers were deemed suitable for review, 13 of these were of sufficient quality to permit systematic data analysis. The primary outcome measure was survival to hospital discharge. The secondary outcome measure was functional neurological status at last follow-up. Analysis revealed a 67.7% survival to discharge and a 61.5% rate of good neurological recovery for patients presenting with pure hypothermic cardiac arrest. This was in marked contrast to a 23.4% survival and a 9.4% rate of good neurological outcome in those presenting with a mixed hypoxic/hypothermic arrest. Other data revealed a survival benefit for patients presenting with deep hypothermia without cardiac arrest treated with ECAR compared to those treated with conventional rewarming techniques. Hypoxic arrest, serum potassium > 10 mmol/L and presenting rhythm of asystole were found likely be significant predictors of poor outcome. Innovative reperfusion and rewarming strategies are also reviewed.

Long-term outcomes in surgically intervened empyema patients: a systematic review.

BACKGROUND: Pleural empyema is significant cause of morbidity and mortality. Debate in the literature exists regarding the best initial and definitive therapy, with recent research demonstrating superior short-term outcomes with initial surgical intervention. Despite this, the impact of surgical intervention on long-term outcomes has been incompletely described. A systematic review was undertaken to assess the current evidence evaluating the long-term impact of surgical intervention. METHODS: A systematic review was undertaken according to PRISMA guidelines utilizing three databases. Articles included all papers where patients received surgical intervention for empyema with outcomes evaluated beyond 90 days. Two reviewers extracted and reviewed the articles. Grey literature was included. RESULTS: Eleven studies and two abstracts were extracted. One study and two abstracts evaluated the quality of life outcomes, two studies evaluated dyspnoea outcomes, seven studies evaluated long-term lung function and two studies evaluated mortality and re-admissions. 60-65% of patients had no dyspnoea between 2 and 7 years follow-up. In six of seven studies, normal lung function was achieved in patients with chronic fibrothorax with FEV1% and FVC% improvements between 14-30% and 13-50%, respectively. The results from such biased cohorts could not be extrapolated to conclude that surgical intervention results in better outcomes than ICC drainage. Risk of bias was severe for all 11 studies. CONCLUSION: Surgical intervention potentially improves post-operative lung function, long-term dyspnoea, and mortality. The impact this has on quality of life remains unknown. Future prospective trials with homogenous comparative groups are required to better define the role of surgery and its impact on long-term outcomes.

Extending the age criteria of lung transplant donors to 70+ years old does not significantly affect recipient survival.

OBJECTIVES: To determine the impact of older donor age (70+ years) on long-term survival and freedom from chronic lung allograft dysfunction in lung transplant (LTx) recipients. METHODS: A retrospective single-center study was performed on all LTx recipients from 2002 to 2017 and a modern subgroup from 2013 to 2017. Recipients were stratified into 4 groups based on donor lung age (<18, 18-55, 56-69, ≥70 years). Donor and recipient characteristics were compared using χ2 tests for differences in proportions and analysis of variance for differences in means. Univariable and multivariable Cox regression was used to describe differences in long-term survival and freedom from chronic lung allograft dysfunction. RESULTS: Between 2002 and 2017, 1600 LTx were performed, 98 of which were performed from donors aged 70 years or older. Recipients of 70+ years donor lungs were significantly older with a mean age of 55.5 ± 12.9 years old (P = .001) and had more Status 3 (urgent) recipients (37.4%, P = .002). After multivariable regression, there were no significant differences in survival or freedom from chronic lung allograft dysfunction between the 4 strata of recipients. CONCLUSIONS: Lung transplantation using donors 70 years old or older can be considered when all other parameters suggest excellent donor lung function without compromising short- or long-term outcomes.

How we can reduce the environmental impact of our operating theatres: a narrative review.

Climate change is projected to become the leading cause of adverse health outcomes globally, and the healthcare system is a key contributor. Surgical theatres are three to six times more pollutant than other hospital areas, and produce anywhere from a fifth to a third of total hospital waste. Hospitals are increasingly expected to make operating theatres more sustainable, however guidelines to improve environmental sustainability are lacking, and previous research takes a narrow approach to operative sustainability. This paper presents a narrative review that, following a 'review of reviews' approach, aims to summarize the key recommendations to improve the environmental sustainability of surgical theatres. Key domains of discussion identified across the literature included minimisation of volatile anaesthetics, reduction of operating theatre power consumption, optimisation of surgical approach, re-use and re-processing of surgical instruments, waste management, and research, education and leadership. Implementation of individual items in these domains has seen significant reductions in the environmental impact of operative practice. This comprehensive summary of recommendations lays the framework from which providers can assess the sustainability of their practice and for the development of encompassing guidelines to build an environmentally sustainable surgical service.

Ex vivo lung evaluation of single donor lungs when the contralateral lung is rejected increases safe use.

OBJECTIVE: The decision to perform a single-lung transplant (SLT) when the contralateral donor lung is rejected is a challenging scenario. The introduction of ex vivo lung perfusion (EVLP) has improved donor lung assessment, and we hypothesize that it has improved SLT outcomes in this setting. METHODS: A retrospective single-center review of all SLTs performed between 2000 and 2017 was performed in which the years 2000 to 2008 were considered the "pre-EVLP era" and 2009 to 2017 the "EVLP era." Recipients of SLT lungs when the contralateral lung was declined were classified into 3 groups: (1) Pre-EVLP era, (2a) EVLP era but EVLP not used, and (2b) EVLP era and EVLP used. The outcomes of interest were survival, time-to-extubation, and intensive care unit and hospital stay. RESULTS: Among 1692 transplants between 2000 and 2017, 244 (14%) were SLT. SLT rate was similar between eras (pre-EVLP 16% vs EVLP 15%), but more SLTs were performed where the contralateral lung was declined in the EVLP era (pre-EVLP 32% vs EVLP 45%, P = .04). Lungs evaluated on EVLP had lower procurement partial pressure of oxygen and were more often from donation after cardiac death donors. Recipients were generally also sicker, with a greater proportion of rapidly deteriorating recipients. Despite this, outcomes were similar between eras with a trend towards lower 30-day mortality in the EVLP era. CONCLUSIONS: The availability of EVLP allowed for better evaluation of marginal single lungs when the contralateral was declined. This has led to increased use rates with preserved outcomes despite use of more extended criteria organs.

Successful use of factor VIIa to control life-threatening post-operative haemorrhage in a patient on extra-corporeal membrane oxygenation.

Recombinant Factor VII (Novoseven) is gaining recognition as an established treatment option for post-cardiac surgery bleeding. However, little information is available on its use in patients being maintained on Extra-Corporeal Membrane Oxygenation (ECMO) support, particularly in the adult population. We present the first case of the successful use of Factor VIIa to control bleeding in an adult patient on ECMO post cardiac surgery.

A simplified strategy for donor-recipient size-matching in lung transplant for interstitial lung disease.

BACKGROUND: Donor-recipient size-matching has been repeatedly reported to improve outcomes following lung transplantation (LTx). However, there is significant variability in practice and the optimal strategy for size-matching is yet to be defined. For recipients with ILD, size-matching decisions are complicated by concerns regarding the potential impact of pre-LTx pulmonary restriction. We evaluate whether a specific donor-to-recipient size-matching strategy, based on predicted total lung capacity, benefits this patient group. METHODS: This retrospective, single-centre, cohort study describes the post-LTx outcomes of adults who underwent LTx for ILD between 1983 and 2020. Only patients with restrictive physiology, based on pre-LTx pulmonary function testing were included. Post-LTx outcomes were compared based on donor-recipient predicted TLC (D-R pTLC) ratio. A D-R pTLC ratio of ≥0.8 or <1.2 for DLTx, and a D-R pTLC ratio of ≥0.8 or <1.0 for SLTx were classified as 'size-matched'. RESULTS: Five-hundred and fifty LTx recipients met inclusion criteria. Of these, 404 underwent DLTx and 146 underwent SLTx. Size-matching was achieved in 78% of DLTx and 47% of SLTx. Overall survival (p = 0.007) and CLAD-free survival (p < 0.001) was significantly improved following a size-matched DLTx, compared to those with D-R pTLC ratios <0.8 or ≥1.2. Size-matching based on a D-R pTLC ratio 0.8≥ <1.0 for SLTX did not significantly improve survival. CONCLUSIONS: D-R pTLC size-matching, based on a ratio of 0.8≥ <1.2 improved post-DLTx outcomes for patients with restrictive lung disease. This is simple to do, and if applied clinically, could improve overall outcomes in lung transplantation.

Deceased-donor lobar lung transplant: A successful strategy for small-sized recipients.

OBJECTIVES: Lobar lung transplantation (LLTx) from deceased donors is a potential solution for donor-recipient size mismatch for small sized recipients. We reviewed our institutional experience to compare outcomes after LLTx to standard lung transplantation (LTx). METHODS: We retrospectively reviewed transplants in our institution from January 2000 to December 2017. LLTx early- and long-term outcomes were compared with LTx. Additional analysis of outcomes was performed after dividing the cohort into 2 eras (era 1, 2000-2012; era 2, 2013-2017). RESULTS: Among the entire cohort (1665), 75 were LLTx (4.5%). Compared with LTx, LLTx were more frequently bridged to transplant with extracorporeal life support or mechanical ventilation and were transplanted in a rapidly deteriorating status (respectively, 20% vs 4.4%, P = .001; 22.7% vs 7.9, P < .001; and 41.3% vs 26.5%, P = .013). LLTx had longer intensive care unit and hospital lengths of stay (respectively, median 17 vs 4 days, and 45 vs 23, both P < .001), and greater 30-day mortality (13.3% vs 4.3%, P = .001) and 90-day mortality (17.3% vs 7.2%, P = .003). In era 2, despite a significantly greater 30-day mortality (10.8% vs 2.8%, P = .026), there was no significant difference in 90-day mortality between LLTx and LTx (13.5% vs 5.1%, P = .070). Overall survival at 1, 3, and 5 years was not significantly different between LLTx and LTx (73.2% vs 84.4%, 56.9% vs 68.4% and 50.4% vs 55.8, P = .088). CONCLUSIONS: Although LLTx is a high-risk procedure, both mid- and long-term survival are comparable with LTx in all cohorts in the modern era. LLTx therefore represents a valuable surgical option for small-sized recipients.

Preoperative Extracorporeal Membrane Oxygenation and Plasmapheresis for Urgent Pulmonary Endarterectomy in Heparin-Induced Thrombocytopenia-Positive Patient.

Pulmonary endarterectomy is the treatment of choice for chronic thromboembolic pulmonary hypertension. This case report outlines the importance of venoarterial extracorporeal membrane oxygenation and plasmapheresis as two important options in the management of heparin-induced thrombocytopenia-positive patients requiring urgent pulmonary endarterectomy.

Medium-term outcomes after pulmonary valve replacement with the Freestyle valve for congenital heart disease: a case series.

OBJECTIVES: The Freestyle valve may be used for pulmonary valve replacement (PVR). Whether its stentless design and anticalcification treatment improve durability relative to alternative bioprostheses, however, is unknown and long-term data are lacking. METHODS: We performed a retrospective review of all Freestyle PVRs performed by a single surgeon in two institutions. All patients were contacted for follow-up to establish survival, New York Heart Association class and reintervention. Up to date, echocardiography was obtained to assess valve function. Perioperative factors associated with structural valve dysfunction (SVD) were assessed using Cox regression. RESULTS: Between 2000 and 2014, PVR with a Freestyle valve was performed in 114 patients with congenital heart disease. There were 70 males and 44 females. The median age was 21 years (interquartile range 11-35 years). The median clinical and echocardiographic follow-up was 62 months (interquartile range 35-115 months, n = 110) and 58 months (interquartile range 30-93 months, n = 107), respectively. Follow-up was complete for 107 of 114 patients (94%). The survival rate was 95% at 5 years and 91% at 10 years. The rate of freedom from SVD at 5 years was 82%, and at 10 years was 61%. The reintervention-free survival rate was 85% at 5 years, and 71% at 10 years. CONCLUSION: The Freestyle valve in the pulmonary position in a congenital population is associated with low medium-term incidences of SVD and reintervention. It performs equally well to the homograft when a conduit is required and can be considered a valid alternative to stented bioprostheses when PVR alone is required.

Surgical Results and Outcomes After Reimplantation for the Management of Anomalous Aortic Origin of the Right Coronary Artery.

BACKGROUND: Anomalous aortic origin of the right coronary artery (AAORCA) has been reported to cause myocardial ischemia, leading to angina, dyspnea, and decreased exercise tolerance. Reimplantation is a repair technique devised to exclude the abnormal intramural portion of the anomalous artery and avoid the known late attrition of saphenous vein grafts. Our study aims to evaluate the medium-term clinical outcomes with this technique. METHODS: A retrospective review was made of patients who underwent repair of AAORCA by reimplantation between 2002 and 2014 in two institutions in Western Australia. Follow-up computed tomography coronary angiography was used to assess the status of the reimplanted right coronary artery (RCA). Data on survival, freedom from symptoms, cardiac events, and cardiac interventions were also analyzed. RESULTS: Of the 16 patients (aged 17 to 70 years old), 14 (88%) were symptomatic before surgery, with angina (50%) and exertional dyspnea (56%) being the most common symptoms. Surgical reimplantation was successful in 15 patients (94%) without operative mortality. One patient required saphenous vein bypass grafting of the RCA intraoperatively after presumed failed repair and difficulty weaning from cardiopulmonary bypass. All patients who had successful reimplantation of AAORCA were symptom-free after surgery, and none had subsequent cardiac events attributable to the RCA or required further interventions. Ten patients (67%) had computed tomography coronary angiography after surgery; none had stenosis, kinking, or compression of the RCA by the pulmonary artery. Two further patients (including the patient who underwent saphenous vein grafting for presumed failed reimplantation) underwent conventional angiography, which demonstrated patent reimplantations. CONCLUSIONS: To the best of our knowledge, this is the largest reported series of anomalous RCA managed by surgical reimplantation. Our results suggest that this technique is safe and has excellent medium to long-term results regarding symptom-free survival.

Successful 2,000-Kilometer International Transfer of an Infant Receiving Extracorporeal Membrane Oxygenation for Severe Respiratory Failure.

There is minimal reported experience with long-range retrieval of pediatric patients receiving extracorporeal membrane oxygenation (ECMO) support. We report the case of a 10-month old boy with necrotizing staphylococcal pneumonia complicated by a bronchopleural fistula, who was successfully retrieved and transported while receiving ECMO to our unit in Sydney, Australia, from a referring hospital 2,000 kilometers away in the Pacific Islands. He was successfully weaned from ECMO to receive single-lung ventilation after 13 days, and he underwent surgical repair of his bronchopleural fistula through a thoracotomy 3 days after decannulation. He has made a full recovery.

Sternal cables are not superior to traditional sternal wiring for preventing deep sternal wound infection.

OBJECTIVES: Deep sternal wound infection is a devastating complication of cardiac surgery. In the current era of increasing patient comorbidity, newer techniques must be evaluated in attempts to reduce the rates of deep sternal wound infection. METHODS: A randomized controlled trial comparing sternal closure with traditional sternal wires in figure-8 formation with the Pioneer cabling system® from Medigroup after adult cardiac surgery was performed. RESULTS: A total of 273 patients were enrolled with 137 and 135 patients randomized to sternal wires and cables group, respectively. Baseline characteristics between the two groups were well balanced. Deep sternal wound infection occurred in 0.7% of patients in the wires group and 3.7% of patients in the cables group (absolute risk difference = -3.0%, 95% confidence interval: -7.7 to 0.9%; P = 0.12). Patients in the cables group were extubated slightly earlier than those in the sternal wires group postoperatively (9.7 vs 12.8 h; P = 0.03). There was, however, no significant difference in hospital and follow-up pain scores or analgesia requirements. CONCLUSIONS: The Pioneer sternal cabling system appears to facilitate early extubation after adult cardiac surgery, but it does not reduce the rate of deep sternal infectionAustralian New Zealand Clinical Trials Registry: ANZCTR-ACTRN12615000973516.

Fatal Acute Appendicitis in a Neonate With Congenital Heart Disease.

We describe a case of fatal acute appendicitis in a neonate associated with congenital cardiac disease requiring staged surgery. Neonatal appendicitis is extremely rare and usually associated with prematurity and congenital abdominal conditions. This report serves to highlight the risk of this disease due to vascular insufficiency and ischemia in neonates with congenital cardiac disease and highlight the importance of considering this diagnosis in such a neonate with unexplained sepsis even in the absence of clear abdominal signs.