Patrick Chan

Efficacy study of video-assisted thoracoscopic surgery pleurodesis for spontaneous pneumothorax

BACKGROUND This study aims to assess the efficacy of video-assisted thoracoscopic surgery pleurodesis in the treatment of spontaneous pneumothorax with particular reference to the rate of recurrence after abrasion pleurodesis and postoperative neuralgia. METHODS One hundred one patients who underwent 109 video-assisted thoracoscopic surgery pleurodesis procedures in the Austin & Repatriation Medical Centre between January 1992 and June 1998 were identified from a computerized database. The follow-up period was from 8 months to 7 years and 1 month (mean, 44.4 months). Patients were telephoned and asked as to whether recurrence occurred, and if so, when it occurred and how it was treated. They were asked to grade their current pain level from 0 to 6. RESULTS Eighty-two patients were contacted, corresponding to 88 video-assisted thoracoscopic surgery pleurodesis procedures that were followed up (80.7%). There were five recurrences (5.7%). The pain level was rated as 0 in 64 cases (72.7%), 1 in 27 cases (23.9%), 2 in 1 case (1.1%), and 3 in 2 cases (2.3%). CONCLUSIONS These data suggest that video-assisted thoracoscopic surgery pleurodesis is a valid alternative to thoracotomy with pleurectomy for treatment of spontaneous pneumothorax with an acceptable recurrence rate and minimal amount of postoperative neuralgia.

Repair of rheumatic mitral stenosis with bicommissural release, anterior leaflet augmentation and oversized annuloplasty

Rheumatic mitral valve disease often manifests with leaflet fibrosis, commissural fusion and early calcific degeneration. The thickening and fibrosis of the valvular and subvalvular apparatus has made prosthetic mitral replacement the traditional surgical solution. However, favourable valve morphology in some patients may permit a durable mitral repair rather than replacement. There is growing interest in reparative techniques that durably improve the mitral orifice while preserving the subvalvular apparatus. Many of these techniques are technically challenging and require complex resections with intricate chordal adjustments, which may have limited their global acceptance. In this report, we outline a three-step technique that does not require significant resection or involve the use of neochords. This offers a potentially simplified approach to the repair of rheumatic mitral stenosis.

Nanonet force microscopy for measuring forces in single smooth muscle cells of the human aorta

Nanonet force microscopy (NFM) measures forces exerted on or felt by cells attached to fiber nanonets. NFM is applied to cardiovascular pathologies to elucidate disease mechanisms in human patient smooth muscle cells under various stresses (oxidative and single and cyclic mechanical perturbations) to quantitate passive and reactive force modulation.

The Effect of Comprehensive Society of Thoracic Surgeons Quality Improvement on Outcomes and Failure to Rescue

BACKGROUND The Society of Thoracic Surgeons (STS) quality benchmarks guide clinical outcome improvement in cardiac surgery. Failure to rescue (FTR) from postoperative morbidity is a proposed metric of program quality. We examined the effect of a quality improvement initiative guided by STS quality measures on outcomes and FTR. METHODS Prospectively collected STS data on 3,065 consecutive patients who underwent nonemergency cardiac operations at a single institution from January 1, 2010, to January 31, 2014, were retrospectively analyzed. On January 1, 2012, the quality improvement initiative was implemented. Clinical outcomes and FTR rates were compared between operations performed before (group A) and after (group B) implementation. RESULTS STS predicted preoperative mortality and composite of mortality plus morbidity were similar in group A and group B (2.9% ± 3.7% vs 3.1% ± 4.0%, p = 0.21; 17.8% ± 12.1% vs 18.3% ± 12.4%, p = 0.24, respectively). However, the observed mortality and composite mortality plus morbidity were lower in group B vs group A (31 of 1,576 [2.0%] vs 46 of 1,489 [3.1%], p = 0.05; 168 of 1,576 [10.7%] vs 301 of 1,489 [20.2%], p = 0.0001, respectively). Despite clinical outcome improvement, no differences in FTR rates were observed across all seven major morbidity indicators in group A vs B (35 of 290 [12.1%] vs 19 of 156 [12.1%], p = 1.00, respectively). The finding of similarity in the FTR rate remained consistent during procedural subgroup analysis for isolated coronary artery bypass grafting in group A vs B (22 of 174 [12.6%] vs 9 of 77 [11.7%], p = 1.00, respectively). CONCLUSIONS Implementation of quality improvement initiatives significantly improves outcomes without affecting FTR rates. Further study is needed to determine if FTR provides additive value to quality assessment over existing STS metrics.

Trileaflet aortic valve reconstruction using glutaraldehyde fixed autologous pericardium

Aortic valve replacement (AVR) has been considered the gold standard for surgical treatment of aortic stenosis (AS). However, the prostheses used for replacement are not perfect—with mechanical valve requiring anticoagulation and bioprosthetic valves having issues with durability. Recently, there have been an influx of reconstructive techniques. However, these techniques are underutilized due to the complexity of the technique. One of the techniques that has shown promising long-term results is the trileaflet aortic valve reconstruction using glutaraldehyde fixed autologous pericardium. Once the autologous pericardium is fixed in glutaraldehyde, the aortotomy is done. The leaflets of the diseased aortic valve are removed, along with any calcium along the annulus. The commissural distances are then measured using custom sizers which correspond to a template used to sketch out neo-leaflets. The three neo-leaflets are attached using a running 4-0 polypropylene sutures. Once the valve reconstruction is completed, coaptation of the three cusps is checked by using saline and negative pressure on the left ventricular vent. Once the aortotomy is closed and the patient comes off cardiopulmonary bypass, the integrity of the leaflets are once again checked by transesophageal echocardiography. This standardized technique offers excellent long-term results and is reproducible.

Technology-Enhanced Simulation Improves Trainee Readiness Transitioning to Cardiothoracic Training

OBJECTIVE Transitioning from medical school and general surgery training to cardiothoracic (CT) surgical training poses unique challenges for trainees and patient care. We hypothesized that participation in technology-enhanced simulation modules that provided early exposure to urgent/emergent CT patient problems would improve cognitive skills and readiness to manage common urgencies/emergencies. DESIGN Traditional and integrated cardiothoracic residents at our institution participated in a technology-enhanced simulation curriculum. The course comprised of didactics, hands-on simulation, virtual models, and mock oral examinations. Residents also were given a validated pretest and post-test to evaluate knowledge retention and integration. Resident performance was graded using a previously validated objective structured clinical examination. Resident perception of course usefulness and relevance was determined through the completion of a perception survey. SETTING This study occurred at the University of Pittsburgh School of Medicine with the Department of Cardiothoracic Surgery. The facility used was the Peter Winter Institute for Simulation, Education and Research. PARTICIPANTS From 2013 to 2015, 25 traditional and integrated cardiothoracic residents participated in these training modules who have completed all portions of the simulation were used for analysis. RESULTS For our participants, knowledge base significantly increased by 7.9% (pretest = 76.0% vs. post-test = 83.9%, p < 0.01). According to trained-rater evaluation, 93.6% of responses to the 11 objective structured clinical examination competencies were deemed adequate. Postcourse perception survey demonstrated 92% of participants scoring the sessions as important or very important toward development and confidence in managing the cardiothoracic scenarios. These findings were present despite historical assumption that these learners were prepared for complex patient care. CONCLUSIONS After completing a technology-enhanced course combining didactics, simulation, and real-time assessment, residents demonstrated objective improvements in cognitive skills and readiness in managing CT patients. Resident postcourse feedback indicated enhanced confidence, suggesting increased preparedness transitioning to CT surgery. This has strong implications for improved patient safety during these potentially labile transition periods.