Survival after partial heart transplantation in a piglet model.

Partial heart transplantation (PHT) is a novel surgical approach that involves transplantation of only the part of the heart containing a valve. The rationale for this approach is to deliver growing heart valve implants that reduce the need for future re-operations in children. However, prior to clinical application of this approach, it was important to assess it in a preclinical model. To investigate PHT short-term outcomes and safety, we performed PHT in a piglet model. Yorkshire piglets (n = 14) were used for PHT of the pulmonary valve. Donor and recipient pairs were matched based on blood types. The piglets underwent PHT at an average age of 44 days (range 34-53). Post-operatively, the piglets were monitored for a period of two months. Of the 7 recipient piglets, one mortality occurred secondary to anesthesia complications while undergoing a routine echocardiogram on post-operative day 19. All piglets had appropriate weight gain and laboratory findings throughout the post-operative period indicating a general state of good health and rehabilitation after undergoing PHT. We conclude that PHT has good short-term survival in the swine model. PHT appears to be safe for clinical application.

Surgical Protocol for Partial Heart Transplantation in Growing Piglets.

Partial heart transplantation is a new approach to deliver growing heart valve implants. Partial heart transplants differ from heart transplants because only the part of the heart containing the necessary heart valve is transplanted. This allows partial heart transplants to grow, similar to the valves in heart transplants. However, the transplant biology of partial heart transplantation remains unexplored. This is a critical barrier to progress of the field. Without knowledge about the specific transplant biology of partial heart transplantation, children with partial heart transplants are empirically treated like children with heart transplants because the valves in heart transplants are known to grow. In order to progress the field, an animal model for partial heart transplantation is necessary. Here, we contribute our surgical protocol for partial heart transplantation in growing piglets. All aspects of partial heart transplantation, including the donor procedure, the recipient procedure, and recipient perioperative care are described in detail. There are important nuances in the conduct of virtually all aspects of open heart surgery that differs in piglets from humans. Our surgical protocol, which is based on our experience with 34 piglets, will allow other investigators to leverage our experience to seek fundamental knowledge about the nature of partial heart transplants. This is significant because the partial heart transplant model in piglets is complex and very resource intensive.

Partial Heart Transplantation - How to Change the System.

Partial heart transplantation is the first clinically successful approach to deliver growing heart valve implants. To date, 13 clinical partial heart transplants have been performed. However, turning partial heart transplantation into a routine procedure that is available to all children who would benefit from growing heart valve implants poses formidable logistical challenges. Firstly, a supply for partial heart transplant donor grafts needs to be developed. This challenge is complicated by the scarcity of donor organs. Importantly, the donor pools for orthotopic heart transplants, partial heart transplants and cadaver homografts overlap. Secondly, partial heart transplants need to be allocated. Factors relevant for equitable allocation include the indication, anatomical fit, recipient clinical status and time on the wait list. Finally, partial heart transplantation will require regulation and oversight, which only recently has been undertaken by the Food and Drug Administration, which regulates human cellular and tissue-based products. Overcoming these challenges will require a change in the system. Once this is achieved, partial heart transplantation could open new horizons for children who require growing tissue implants.

Textbook Outcome for Superior Cavopulmonary Connection: A Metric for Single Ventricle Heart Surgery.

Background: To develop a more holistic measure of congenital heart center performance beyond mortality, we created a composite "textbook outcome" (TO) for the Glenn operation. We hypothesized that meeting TO would have a positive prognostic and financial impact. Methods: This was a single center retrospective study of patients undergoing superior cavopulmonary connection (bidirectional Glenn or Kawashima ± concomitant procedures) from 2005 to 2021. Textbook outcome was defined as freedom from operative mortality, reintervention, 30-day readmission, extracorporeal membrane oxygenation, major thrombotic complication, length of stay (LOS) >75th percentile (17d), and mechanical ventilation duration >75th percentile (2d). Multivariable logistic regression and Cox proportional hazards modeling were used. Results: Fifty-one percent (137/269) of patients met TO. Common reasons for TO failure were prolonged LOS (78/132, 59%) and ventilator duration (67/132, 51%). In multivariable analysis, higher weight [odds ratio, OR: 1.44 (95% confidence interval, CI: 1.15-1.84), P = .002] was a positive predictor of TO achievement while right ventricular dominance [OR 0.47 (0.27-0.81), P = .007] and higher preoperative pulmonary vascular resistance [OR 0.58 (0.40-0.82), P = .003] were negative predictors. After controlling for preoperative factors and excluding operative mortalities, TO achievement was independently associated with a decreased risk of death over long-term follow-up [hazard ratio: 0.50 (0.25-0.99), P = .049]. Textbook outcome achievement was also associated with lower direct cost of care [$137,626 (59,333-167,523) vs $262,299 (114,200-358,844), P < .0001]. Conclusion: Achievement of the Glenn TO is associated with long-term survival and lower costs and can be predicted by certain risk factors. As outcomes continue to improve within congenital heart surgery, operative mortality will become a less informative metric. Textbook outcome analysis may represent a more balanced measure of a successful outcome.

Center-level factors associated with shorter length of stay following stage 1 palliation: An analysis of the national pediatric cardiology quality improvement collaborative registry.

BACKGROUND: Stage 1 single ventricle palliation (S1P) has the longest length of stay (LOS) of all benchmark congenital heart operations. Center-level factors contributing to prolonged hospitalization are poorly defined. METHODS: We analyzed data from infants status post S1P included in the National Pediatric Cardiology Quality Improvement Collaborative Phase II registry. Our primary outcome was patient-level LOS with days alive and out of hospital before stage 2 palliation (S2P) used as a balancing measure. We compared patient and center-level characteristics across quartiles for median center LOS, and used multivariable regression to calculate center-level factors associated with LOS after adjusting for case mix. RESULTS: Of 2,510 infants (65 sites), 2037 (47 sites) met study criteria (61% male, 61% white, 72% hypoplastic left heart syndrome). There was wide intercenter variation in LOS (first quartile centers: median 28 days [IQR 19, 46]; fourth quartile: 62 days [35, 95], P < .001). Mortality prior to S2P did not differ across quartiles. Shorter LOS correlated with more pre-S2P days alive and out of hospital, after accounting for readmissions (correlation coefficient -0.48, P < .001). In multivariable analysis, increased use of Norwood with a right ventricle to pulmonary artery conduit (aOR 2.65 [1.1, 6.37]), shorter bypass time (aOR 0.99 per minute [0.98,1.0]), fewer additional cardiac operations (aOR 0.46 [0.22, 0.93]), and increased use of NG tubes rather than G tubes (aOR 7.03 [1.95, 25.42]) were all associated with shorter LOS centers. CONCLUSIONS: Modifiable center-level practices may be targets to standardize practice and reduce overall LOS across centers.

Understanding and Managing Direct Operating Room Supply Costs in Cardiac Surgery.

BACKGROUND: Value-based bundles require surgeons to understand their costs. Current approaches to cost reporting are confusing and difficult to reproduce. Using the Epic surgical receipt function, we describe an intuitive and systematic approach for evaluating financial data within the operating room. METHODS: We conducted a retrospective review of all congenital cardiac procedures performed at a single academic medical center between January 1, 2020, and January 1, 2021. Direct operating room supply costs were obtained using the Epic surgical receipt function. Costs were analyzed on the basis of contribution to total annual cost and variability in case cost. Implications for strategies identified within congenital cardiac surgery were then evaluated in adult cardiac surgery. RESULTS: Five procedures representing 71 patients accounted for more than 50% of the total direct operating room supply costs (left ventricular assist device, Norwood procedure, pulmonary valve replacement, right ventricle-to-pulmonary artery shunt, and aortic arch augmentation). Disposable vascular clips, suture brand preference, and surgical patch materials accounted for 3.7%, 6.6%, and 26.5% of annual direct operating room supply costs, respectively. Improvements to these categories would represent 12% to 14% ($250 000) in annual savings without an anticipated effect on outcomes. Across adult and congenital cardiac surgery, 95% of all name-brand suture use was tied to preference cards. An opt-in vs default approach to name-brand polypropylene suture could save more than $250 000 annually. CONCLUSIONS: The surgical receipt represents a reliable and intuitive way for reporting surgical costs. Systematically analyzing costs and their impact on outcomes will help surgeons improve the value of care they provide.

Minimally Invasive Approach for Cardiac Hemangioma Resection in a Teenager.

Cardiac hemangiomas are a rare tumor traditionally resected by median sternotomy. We performed a minimally invasive right ventricular cardiac hemangioma resection via a left anterior mini-incision (LAMI). The procedure was without complication, and the patient was discharged on postoperative day 2. The LAMI has been used broadly by our team for operations involving the right ventricular outflow tract, as an alternative to median sternotomy. Here we show that it can also be used for the resection of a cardiac tumor.

Early identification of patients at risk for delayed recovery of ambulation after elective abdominal surgery.

BACKGROUND: Recovery of preoperative ambulation levels 1 month after surgery represents an important patient-centered outcome. The objective of this study is to identify clinical factors associated with the inability to regain baseline preoperative ambulation levels 28 days postoperatively. METHODS: This is a prospective cohort study enrolling patients scheduled for elective inpatient abdominal operations. Daily ambulation (steps/day) was measured with a wristband accelerometer. Preoperative steps were recorded for at least 3 full calendar days before surgery. Postoperatively, daily steps were recorded for at least 28 days. The primary outcome was delayed recovery of ambulation, defined as inability to achieve 50% of preoperative baseline steps at 28 days postoperatively. RESULTS: A total of 108 patients were included. Delayed recovery (< 50% of baseline preoperative steps/day) occurred in 32 (30%) patients. Clinical factors associated with delayed recovery after multivariable logistic regression included longer operative time (OR 1.37, 95% CI 1.05-1.79), open operative approach (OR 4.87, 95% CI 1.64-14.48) and percent recovery on POD3 (OR 0.73, 95% CI 0.56-0.96). In addition, patients with delayed ambulation recovery had increased rates of postoperative complications (16% vs 1%, p < 0.01) and readmission (28% vs 5%, p < 0.01). CONCLUSION: After elective inpatient abdominal operations, nearly one in three patients do not recover 50% of their baseline preoperative steps 28 days postoperatively. Factors that can be used to identify these patients include longer operations, open operations and low ambulation levels on postoperative day #3. These data can be used to target rehabilitation efforts aimed at patients at greatest risk for poor ambulatory recovery.

Decreases in daily ambulation forecast post-surgical re-admission.

BACKGROUND: Surgical readmissions are clinically and financially problematic. Our purpose is to determine if a decrease in postoperative ambulation (steps/day) is associated with hospital readmission. METHODS: In this prospective cohort study, patients undergoing elective operations wore an accelerometer activity tracker to measure steps/day for 28 consecutive postoperative days. The primary outcome was hospital readmission. The change in steps/day over two consecutive days prior to the day of the readmission were examined. Predetermined thresholds for decreases of consecutive daily ambulation levels were used to calculate sensitivity and specificity for the outcome of hospital readmission. RESULTS: 215 patients (aged 63 ± 12 years) were included. Readmission occurred in 10% (n = 21). For each of the first 28-postoperative days, the entire cohort had an average daily step increase of 136 ± 146 steps/day (Spearman correlation rho = 0.990; p < 0.001). A decrease in steps for two consecutive days of >50% from the prior day had a 79% sensitivity and 90% specificity for hospital readmission. CONCLUSIONS: A decrease of >50% daily ambulation (steps/day) over two consecutive post-discharge days accurately forecasts hospital readmission. The implications of these findings are that monitoring daily ambulation could serve as a form of outpatient telemetry aiding to forecast post-surgical readmissions.

Monopolar stray energy in robotic surgery.

INTRODUCTION: Stray energy transfer from monopolar radiofrequency energy during laparoscopy can be potentially catastrophic. Robotic surgery is increasing in popularity; however, the risk of stray energy transfer during robotic surgery is unknown. The purpose of this study was to (1) quantify stray energy transfer using robotic instrumentation, (2) determine strategies to minimize the transfer of energy, and (3) compare robotic stray energy transfer to laparoscopy. METHODS: In a laparoscopic trainer, a monopolar instrument (L-hook) was activated with DaVinci Si (Intuitive, Sunnyvale, CA) robotic instruments. A camera and assistant grasper were inserted to mimic a minimally invasive cholecystectomy. During activation of the L-hook, the non-electric tips of the camera and grasper were placed adjacent to simulated tissue (saline-soaked sponge). The primary outcome was change in temperature from baseline (°C) measured nearest the tip of the non-electric instrument. RESULTS: Simulated tissue nearest the robotic grasper increased an average of 18.3 ± 5.8 °C; p < 0.001 from baseline. Tissue nearest the robotic camera tip increased (9.0 ± 2.1 °C; p < 0.001). Decreasing the power from 30 to 15 W (18.3 ± 5.8 vs. 2.6 ± 2.7 °C, p < 0.001) or using low-voltage cut mode (18.3 ± 5.8 vs. 3.1 ± 2.1 °C, p < 0.001) reduced stray energy transfer to the robotic grasper. Desiccating tissue, in contrast to open air activation, also significantly reduced stray energy transfer for the grasper (18.3 ± 5.8 vs. 0.15 ± 0.21 °C, p < 0.001) and camera (9.0 ± 2.1 vs. 0.24 ± 0.34 °C, p < 0.001). CONCLUSIONS: Stray energy transfer occurs during robotic surgery. The assistant grasper carries the highest risk for thermal injury. Similar to laparoscopy, stray energy transfer can be reduced by lowering the power setting, utilizing a low-voltage cut mode instead of coagulation mode and avoiding open air activation. These practical findings can aid surgeons performing robotic surgery to reduce injuries from stray energy.

Electromagnetic interference on cardiac pacemakers and implantable cardioverter defibrillators during endoscopy as reported to the US Federal Drug Administration.

INTRODUCTION: More than 3 million patients have a cardiac implanted electronic device (CIED) such as a pacemaker or implanted cardioverter-defibrillator in the USA. These devices are susceptible to electromagnetic interference (EMI) leading to malfunction and injury. Radiofrequency energy, the most common modality for obtaining hemostasis during endoscopy, is the most common source of EMI. Few studies have evaluated the effect of endoscopic radiofrequency energy on CIEDs. We aim to characterize CIED dysfunction related to endoscopic procedures. We hypothesize that EMI from endoscopic energy can result in patient injury. METHODS: We queried the Manufacturer and User Facility Device Experience (MAUDE) database for CIED dysfunction related to electrosurgical devices over a 10-year period (2009-2019). CIED dysfunction events were identified using seven problem codes (malfunction, electromagnetic interference, ambient noise, pacing problem, over-sensing, inappropriate shock, defibrillation). These were cross-referenced for the terms "cautery, electrocautery, endoscopy, esophagus, colonoscopy, colon, esophagoscopy, and esophagogastroduodenoscopy." Reports were individually reviewed to confirm and characterize CIED malfunction due to an endoscopic procedure. RESULTS: A search for CIED dysfunction resulted in 43,759 reports. Three hundred and eleven reports (0.7%) were associated with electrocautery, and of these, 45 reports (14.5%) included endoscopy. Ten reports involving endoscopy (22%) specified upper (3, 7%) or lower (7, 16%) endoscopy while the remainder were non-specific. Twenty-six of reports involving endoscopy (58%) suffered injury because of CIED dysfunction: Of these, 17 (65%) received inappropriate shocks, 5 (19%) had pacing inhibition with bradycardia or asystole, 3 (12%) had CIED damage requiring explant and replacement, and 1 (4%) patient suffered ventricular tachycardia requiring hospital admission. CONCLUSION: The use of energy during endoscopy can cause dysfunction of CIEDs. This most commonly results in inappropriate defibrillation, symptomatic bradycardia, and asystole. Patients with CIEDs undergoing endoscopy should undergo pre- and post-procedure device interrogation and re-programming to avoid patient injury.

Stray energy transfer in single-incision robotic surgery.

INTRODUCTION: Stray energy transfer from surgical monopolar radiofrequency energy instruments can cause unintended thermal injuries during laparoscopic surgery. Single-incision laparoscopic surgery transfers more stray energy than traditional laparoscopic surgery. There is paucity of published data concerning stray energy during single-incision robotic surgery. The purpose of this study was to quantify stray energy transfer during traditional, multiport robotic surgery (TRS) compared to single-incision robotic surgery (SIRS). METHODS: An in vivo porcine model was used to simulate a multiport or single-incision robotic cholecystectomy (DaVinci Si, Intuitive Surgical, Sunnyvale, CA). A 5 s, open air activation of the monopolar scissors was done on 30 W and 60 W coag mode (ForceTriad, Covidien-Medtronic, Boulder, CO) and Swift Coag effect 3, max power 180 W (VIO 300D, ERBE USA, Marietta, GA). Temperature of the tissue (°C) adjacent to the tip of the assistant grasper or the camera was measured with a thermal camera (E95, FLIR Systems, Wilsonville, OR) to quantify stray energy transfer. RESULTS: Stray energy transfer was greater in the SIRS setup compared to TRS setup at the assistant grasper (11.6 ± 3.3 °C vs. 8.4 ± 1.6 °C, p = 0.013). Reducing power from 60 to 30 W significantly reduced stray energy transfer in SIRS (15.3 ± 3.4 °C vs. 11.6 ± 3.3 °C, p = 0.023), but not significantly for TRS (9.4 ± 2.5 °C vs. 8.4 ± 1.6 °C, p = 0.278). The use of a constant voltage regulating generator also minimized stray energy transfer for both SIRS (0.7 ± 0.4 °C, p < 0.001) and TRS (0.7 ± 0.4 °C, p < 0.001). CONCLUSIONS: More stray energy transfer occurs during single-incision robotic surgery than multiport robotic surgery. Utilizing a constant voltage regulating generator minimized stray energy transfer for both setups. These data can be used to guide robotic surgeons in their use of safe, surgical energy.