Retraction speed and chronic poststernotomy pain: A randomized controlled trial.

OBJECTIVES: Approximately 30% of patients develop chronic poststernotomy pain (CPSP) following cardiac surgery with sternal retraction. Risk factors have been described but no causal determinants identified. Investigators hypothesized that opening the sternum slowly would impart less force (and thereby less nerve/tissue damage) and translate to a reduced incidence of CPSP. The main objectives were to determine whether or not slower sternal retraction would reduce the incidence of CPSP and improve health-related quality of life. METHODS: Patients undergoing coronary artery bypass graft surgery were recruited to this randomized controlled trial. Patients were randomized to slow or standard retraction (ie, sternum opened over 15 minutes vs 30 seconds, respectively). Although the anesthesiologist and surgeon were aware of the randomization, the patients, assessors, and postoperative nursing staff remained blinded. Sternotomy pain and analgesics were measured in hospital. At 3, 6, and 12 months postoperatively, all patients completed the Medical Outcomes Survey Short Form and reported on CPSP and complications requiring rehospitalization. Thirty-day rehospitalizations and mortality were recorded. RESULTS: In total, 326 patients consented to participate and 313 were randomized to slow (n = 159) versus standard retraction (n = 154). No clinically relevant differences were detected in acute pain, analgesic consumption, or the incidence of CPSP or health-related quality of life. Although the slow group had significantly more hospitalizations at 3 and 12 months postoperatively, the reasons were unrelated to retraction speed. No differences were observed in 30-day rehospitalizations or mortality. CONCLUSIONS: All outcomes were consistent with previous reports, but no clinically significant differences were observed with retraction speed.

Quantifying neurological function in patients undergoing transcatheter aortic valve implantation.

Background: Transcatheter aortic valve implantation (TAVI) is a routine procedure that is often performed on older adults that are high-risk patients with severe aortic stenosis. Patients after TAVI may experience neurological complications. However, there is a lack of objective neurological testing available for patients undergoing cardiac surgery. Objective: This brief communication seeks to explore the use of robotic technology to quantify distinctive patterns of visuospatial, sensorimotor, and cognitive functioning in patients undergoing TAVI. Methods: Patients undergoing TAVI were recruited for this prospective observational study. Prior to their procedure, study participants performed four robotic reaching tasks using the Kinarm robotic system. Patients repeated the assessment three months after their TAVI procedure. Significant changes in overall task score and parameters were determined. Results: Ten patients were recruited and included in this brief report. In a simple reaching task, patients show significant improvement in performance post-TAVI. However, patients do not improve nor worsen in a complex reaching task after TAVI. Similarly, patients demonstrate impairments in both trail making tasks before and after their TAVI procedure. Conclusions: This study captures the variability in neurological functioning in older patients undergoing TAVI. Robotic technology and quantified assessment procedures can be extremely valuable for detecting perioperative neurological impairments in this patient population.

Does Pacemaker Implantation After Surgical Aortic Valve Replacement Impact Long-Term Morbidity and Mortality? A Focused Review.

Permanent pacing remains a serious complication that can occur in the postoperative period of surgical aortic valve replacement. The reported incidence is variable, and there are many perioperative factors that have been linked with a greater need for permanent pacing. Permanent pacing can also be associated with late lead-related and cardiac complications that can affect late outcome. However, the degree of late dependence on pacemakers is varied, and some studies have shown that a substantial proportion of patients do not need long-term pacing. Some groups have found that permanent pacing was associated with a negative impact on long-term survival in these patients. A common finding among these studies is that the groups of patients with pacemakers had higher preoperative surgical risk and comorbidity status. This makes it difficult to establish whether permanent pacing on its own represents a risk factor for late mortality or whether it is simply a marker that reflects the higher complexity and comorbidities in this group of patients.

Higher Mortality in Women After Coronary Artery Bypass: Meta-analysis and Bias Analysis of Confounding.

BACKGROUND: Some studies suggest that the observed higher mortality in women compared with men after coronary artery bypass grafting (CABG) is due to confounding. Our meta-analysis aimed to (1) summarize the effect of sex on mortality after CABG and (2) identify whether unmeasured confounding likely explains the apparent higher mortality in women. METHODS: We searched MEDLINE, Embase, and CENTRAL databases for studies examining sex and 30-day mortality after CABG. We used random-effects meta-analysis to estimate the summary odds ratio (OR) of mortality in women versus men using (1) unadjusted study results and (2) adjusted study results. Available confounders data from included studies were identified. Using the OR of measured confounders and the risk of death to inform unmeasured confounding effects, we performed bias analysis simulation to correct potential unmeasured confounding in the summary OR. RESULTS: From 7,138 retrieved studies, 112 were included (N = 5,008,262 patients); 25 studies reported adjusted OR (N = 770,450 patients). Overall 30-day mortality was 4.9% in women versus 3.3% in men. The unadjusted summary OR (1.81; 95% confidence interval, 1.72-1.91) and adjusted summary OR (1.40, 95% confidence interval, 1.35-1.45) demonstrated women had an increased risk for 30-day mortality compared with men. Simulations correcting for unmeasured confounding mostly ranged from 1.05 to 1.80, which supports a higher risk for death in women after CABG. CONCLUSIONS: The findings of this review suggest that confounding is unlikely to account for the increased risk for mortality in women after CABG and that biological factors have a causal effect.

Is It Feasible to Implant Sutureless Valves in Presence of Diseased Aortic Root and Aortic Aneurysm?

Sutureless bioprosthetic valves are typically used in patients with a normal-sized aortic root and annulus because of concerns that the stent portion of the valve will not be properly anchored. This report describes an initial case series of sutureless valve implantation in the setting of a diseased aortic root and ascending aortic aneurysm, and it shows that the use of the Perceval valve (LivaNova PLC, London, UK) is feasible in these complex situations.

Study protocol for DICE trial: Video-assisted thoracoscopic surgery decortication versus interventional radiology guided chest tube insertion for the management of empyema.

BACKGROUND: Empyema is a common thoracic surgery presentation, defined as pus in the pleural space. Despite the commonality of empyema, consensus on initial management remains ambiguous. Two standard of care treatment options include inserting a chest tube (thoracostomy) and the administration of intrapleural fibrinolytics, or an initial surgical approach, surgical decortication. Due to the complexity of this pleural space infection, often repeat interventions are required after initial management in order to achieve source control and resolution of clinical symptoms. This study aims to identify the most effective initial management option for empyema. STUDY DESIGN: We present a study protocol for a randomized control trial (RCT) comparing adult individuals with empyema to one of two standard of care initial management options. Participants will be randomized into either interventional radiology guided chest tube insertion with intrapleural fibrinolytics (Dornase 5 mg and Alteplase 10 mg intrapleural twice daily for three days) or video-assisted thoracoscopic surgery (VATS) decortication. METHODS: All adults with empyema meeting inclusion criteria will be invited to participate. They will be randomized into one of two intervention groups; interventional radiology guided chest tube insertion with fibrinolytics or initial VATS decortication. Each intervention will take place within 48 hours of randomization. The primary outcome will be the rate of re-intervention within 30 days. Re-intervention is defined as repeat chest tube insertion, VATS decortication, or decortication via thoracotomy. Secondary outcomes include a change in the size of empyema, length of stay, morbidity, as well as 30-day and 90-day mortality, as well as quality of life measurements. ANTICIPATED IMPACT: This study is aimed at identifying the most effective initial management option for individuals with empyema.

Quantified pre-operative neurological dysfunction predicts outcome after coronary artery bypass surgery.

AIMS: Patients undergoing coronary artery bypass grafting (CABG) surgery may experience neurological impairment. We examined whether intraoperative regional cerebral oxygen saturation (rSO2) and neurological dysfunction prior to surgery, measured by robotic technology, are important predictors of post-operative performance following CABG surgery. METHODS: Adult patients undergoing CABG surgery were recruited for this single-center prospective observational study. Intraoperative rSO2 was captured using the FORESIGHT cerebral oximeter. Neurological assessment was performed pre-operatively and 3 months following surgery using robotic technology and a standardized pen-and-paper assessment. Linear regression models were generated to determine the predictive ability of both intraoperative rSO2 and pre-operative performance on post-operative neurological outcome. RESULTS: Forty patients had complete data available for analysis. Quantified pre-operative performance accounted for a significantly larger amount of variance in post-operative outcome compared to intraoperative rSO2. In particular, pre-operative scoring on a cognitive visuospatial task accounted for 82.2% of variance in post-operative performance (b = 0.937, t(37) = 12.98, p = 1.28e-5). DISCUSSION: Our results suggest that pre-operative performance is a stronger indicator of post-operative neurological outcome than intraoperative rSO2, and should be included as an important variable when elucidating the relationship between cerebral oxygen levels and post-operative neurological impairment. Rigorous neurological assessment prior to surgery can provide valuable information about each individual patient's path to recovery. CONCLUSION: Using robotic technology, quantified neurological impairment prior to CABG surgery may better predict post-operative neurological outcomes, compared to intraoperative rSO2 values.

Road to recovery: a study protocol quantifying neurological outcome in cardiac surgery patients and the role of cerebral oximetry.

INTRODUCTION: Patients undergoing cardiac surgery may experience both short-term and long-term postoperative neurological problems. However, the underlying cause of this impairment is unclear. Regional cerebral oxygen saturation (rSO2) levels may play a role in the development of acute dysfunction, known as postoperative delirium, in addition to longer term outcomes after cardiac surgery. Yet the degree of impairment has been difficult to define, partly due to subjective methods of assessments. This study aims to fill this knowledge gap by determining the relationship between rSO2, postoperative delirium and long-term neurological outcome after cardiac surgery using quantitative robotic technology. METHODS AND ANALYSIS: 95 patients scheduled for elective cardiac surgery will be recruited for this single-centre prospective observational study. Patients will be assessed before as well as 3 and 12 months after their surgery using the Kinarm End-Point Lab and standardised tasks. Intraoperatively, rSO2 and other haemodynamic data will be collected for the duration of the procedure. Following their operation, patients will also be screened daily for delirium during their hospital stay. ETHICS AND DISSEMINATION: This study has been approved by the Health Sciences Research Ethics Board at Queen's University (DMED-1672-14). The results of this study will be published in a peer-review journal and presented at international and/or national conferences as poster or oral presentations. Participants wishing to know the results of this study will be contacted directly on data publication. TRIAL REGISTRATION NUMBER: NCT04081649.

Outcomes of Operative and Nonoperative Treatment of Thoracic Empyema: A Population-Based Study.

BACKGROUND: The optimal management of thoracic empyema remains unclear. This study compared mortality and readmission risk after operative vs nonoperative treatment of thoracic empyema. METHODS: Administrative universal health care data were used to conduct a retrospective population-based cohort study of thoracic empyema in Ontario, Canada. Individuals aged 18 years or older with a hospital discharge diagnosis of thoracic empyema from January 1, 1996, to December 31, 2015, were included. Treatment approach was classified as nonoperative (ie, chest tube with or without fibrinolytics) or operative (video-assisted thoracoscopic surgery [VATS] or open decortication). Modified Poisson regression was used to estimate adjusted risk ratios (RRadj) between treatment (open decortication was the reference group) and (1) death and (2) readmission. Analyses were also stratified by year of admission in 5-year intervals. RESULTS: The study cohort comprised 9014 hospitalized individuals. Individuals treated nonoperatively had higher mortality risk as an inpatient (17.2% vs 10.6%; RRadj, 1.32-1.54), at 30 days (11.1% vs 4.2%; RRadj, 1.86-3.38), 6 months (26.6% vs 15.0%; RRadj, 1.38-1.59), and 1 year (32.3% vs 18.8%; RRadj, 1.38-1.59). No differences in 90-day readmission risk were observed. No effect measure modification was observed in models stratified by year of admission. CONCLUSIONS: Nonoperative management of thoracic empyema was associated with higher risk of mortality compared with surgical decortication. Early thoracic surgical consultation is recommended.

Zone 1 Debranching for Frozen Elephant Trunk and Whole-Body Perfusion.

A 65-year-old man with chronic type A aortic dissection underwent zone 1 debranching and frozen elephant trunk with whole-body perfusion. This approach has the potential to improve technical feasibility of the frozen elephant trunk procedure and reduce its ischemic complications.

Endoscopic radial artery harvesting with a non-sealed approach.

Endoscopic radial artery harvesting is considered a safe and effective approach for graft procurement during coronary artery bypass graft surgery. As an alternative to open techniques, minimally invasive approaches are associated with superior outcomes in terms of morbidity and patients' discomfort, without affecting graft quality, patency rate, and long-term outcomes.  Both sealed and non-sealed systems are available for endoscopic conduit harvesting. Sealed systems require carbon dioxide gas insufflation, which may have a damaging impact on the endothelium. Non-sealed systems do not require carbon dioxide insufflation and thus avoid the potential drawbacks of its use. In this video tutorial, we provide a thorough description of the surgical technique for endoscopic radial artery harvesting using a non-sealed approach.

Endoscopic saphenous vein harvesting with a non-sealed approach.

Endoscopic saphenous vein harvesting is considered a safe and effective approach for graft procurement during coronary artery bypass graft surgery. As an alternative to open techniques, minimally invasive approaches are associated with superior outcomes in terms of morbidity and patients' discomfort, without affecting graft quality, patency rate, and long-term outcomes.  Both sealed and non-sealed systems are available for endoscopic conduit harvesting. Sealed systems require carbon dioxide gas insufflation, which may have a damaging impact on the endothelium. Non-sealed systems do not require carbon dioxide insufflation and thus avoid the potential drawbacks of its use. In this video tutorial, we provide a thorough description of the surgical technique for endoscopic saphenous vein harvesting using a non-sealed approach.

The relationship between cerebral oxygen saturation and quantitative metrics of neurological function after coronary bypass surgery: a feasibility study.

BACKGROUND: It is well-known that patients undergoing coronary artery bypass grafting (CABG) surgery may experience neurological dysfunction following their operation. However, the nature of this dysfunction has not been properly quantified. Furthermore, the relationship between postoperative impairment and cerebral oxygen saturation during surgery has remained unclear. This study aims to define the feasibility of using robotic technology to quantify post-CABG neurocognitive function, and to correlate these objective metrics with intraoperative cerebral oxygenation. METHODS: Neurological function was tested using robotic technology and a standardized questionnaire before and 3 months after surgery. In addition, frontal lobe cerebral oxygenation was recorded using the FORESIGHT near-infrared spectrometer for the duration of the operation. Pre- and postoperative neurological assessment was performed for 24 participants. Of those 24, 20 participants had cerebral oxygenation recorded during their surgery. RESULTS: The cerebral oximeter captured 97.2% of the data. Majority of patients experienced no significant decline in overall neurocognitive function. Abnormal postoperative scores were most frequent in a sensorimotor task that involved additional cognitive load. In this reverse visually guided reaching task, postoperative scores significantly correlated with mean and minimum intraoperative cerebral oxygenation values, with lower values being associated with worse performance. CONCLUSIONS: It is feasible to use robotic technology as a quantitative and objective neurocognitive assessment method for patients undergoing CABG. The relationship between quantitative metrics of neurocognitive function and intraoperative cerebral oxygenation warrants further investigation.

Remote Ischemic Preconditioning in High-risk Cardiovascular Surgery Patients: A Randomized-controlled Trial.

Remote ischemic preconditioning (RIPC) may reduce biomarkers of ischemic injury after cardiovascular surgery. However, it is unclear whether RIPC has a positive impact on clinical outcomes. We performed a blinded, randomized controlled trial to determine if RIPC resulted in fewer adverse clinical outcomes after cardiac or vascular surgery. The intervention consisted of 3 cycles of RIPC on the upper limb for 5 minutes alternated with 5 minutes of rest. A sham intervention was performed on the control group. Patients were recruited who were undergoing (1) high-risk cardiac or vascular surgery or (2) cardiac or vascular surgery and were at high risk of ischemic complications. The primary end point was a composite outcome of mortality, myocardial infarction, stroke, renal failure, respiratory failure, and low cardiac output syndrome, and the secondary end points included the individual outcome parameters that made up this score, as well as troponin-I values. A total of 436 patients were randomized and analysis was performed on 215 patients in the control group and on 213 patients in the RIPC group. There were no differences in the composite outcome between the 2 groups (RIPC: 67 [32%] and control: 72 [34%], relative risk [0.94 {0.72-1.24}]) or in any of the individual components that made up the composite outcome. Additionally, we did not observe any differences between the groups in troponin-I values, the length of intensive care unit stay, or the total hospital stay. RIPC did not have a beneficial effect on clinical outcomes in patients who had cardiovascular surgery.

A Case of Severe Accidental Hypothermia Successfully Treated with Cardiopulmonary Bypass.

After missing for seven days, a 34-year-old female was found with a rectal temperature of 19.8oC. Instead of attempting aggressive rewarming in the emergency department she was directly transferred to the operating room for extracorporeal rewarming. She received cardiopulmonary bypass (CPB) for 66 minutes at an initial warming rate of 12oC/ hour and warmed to 36.2oC. Her postoperative course was complicated by sepsis, which eventually led to bilateral below-knee amputations after refusing antibiotics. She was discharged 22 days after admission, with full neurologic recovery. This remarkable case highlights the emerging role of CPB as the definitive therapy for severe accidental hypothermia.

The histology of human right atrial tissue in patients with high-risk Obstructive Sleep Apnea and underlying cardiovascular disease: A pilot study.

BACKGROUND: Obstructive Sleep Apnea (OSA) results in intermittent hypoxia leading to atrial remodeling, which, among other things, facilitates development of atrial fibrillation. While much data exists on the macrostructural changes in cardiac physiology induced by OSA, there is a lack of studies looking for histologic changes in human atrial tissue induced by OSA which might lead to the observed macrostructural changes. METHODS: A case control study was performed. Patients undergoing coronary artery bypass grafting (CABG) were evaluated for OSA and categorized as high-risk or low-risk. The right atrial tissue samples were obtained during CABG and both microscopic histological analysis and Sirius Red staining were performed. RESULTS: 18 patients undergoing CABG were included; 10 high-risk OSA and 8 low-risk OSA in evenly matched populations. No statistically significant difference between the two groups was observed in amount of myocytolysis (p = 0.181), nuclear hypertrophy (p = 0.671), myocardial inflammation (p = n/a), amyloid deposition (p = n/a), or presence of thrombi (p = n/a), as measured through routine H&E staining. As well, no statistically significant difference in interstitial and epicardial collagen was observed, as measured by Sirius Red staining (for total tissue: p = 0.619: for myocardium: p = 0.776). CONCLUSIONS: In this pilot study there were no observable histological differences in human right atrial tissue from individuals at high- and low-risk for OSA. Further investigation would be required for more definitive results.