Prevention of Unilateral Pulmonary Edema Complicating Robotic Mitral Valve Operations

Anesthesia for Minimal Invasive Cardiac Surgery: The Bonn Heart Center Protocol

The development and adoption of minimally invasive techniques has revolutionized various surgical disciplines and has also been introduced into cardiac surgery, offering patients less invasive options with reduced trauma and faster recovery time compared to traditional open-heart procedures with sternotomy. This article provides a comprehensive overview of the anesthesiologic management for minimally invasive cardiac surgery (MICS), focusing on preoperative assessment, intraoperative anesthesia techniques, and postoperative care protocols. Anesthesia induction and airway management strategies are tailored to each patient's needs, with meticulous attention to maintaining hemodynamic stability and ensuring adequate ventilation. Intraoperative monitoring, including transesophageal echocardiography (TEE), processed EEG monitoring, and near-infrared spectroscopy (NIRS), facilitates real-time assessment of cardiac and cerebral perfusion, as well as function, optimizing patient safety and improving outcomes. The peripheral cannulation techniques for cardiopulmonary bypass (CPB) initiation are described, highlighting the importance of cannula placement to minimize tissue as well as vessel trauma and optimize perfusion. This article also discusses specific MICS procedures, detailing anesthetic considerations and surgical techniques. The perioperative care of patients undergoing MICS requires a multidisciplinary approach including surgeons, perfusionists, and anesthesiologists adhering to standardized treatment protocols and pathways. By leveraging advanced monitoring techniques and tailored anesthetic protocols, clinicians can optimize patient outcomes and promote early extubation and enhanced recovery.

Unilateral pulmonary edema after minimally-invasive bentall procedure - Case report

Introduction

Unilateral pulmonary edema (UPE), a life-threatening complication of cardiac surgery, often occurs after prolonged cardiopulmonary bypass and lung collapse, especially in minimally-invasive cardiac surgery (MICS). The present study reported a young patient with severe UPE after the surgery as well as corresponding clinical treatments. In addition to the supportive treatment of extracorporeal membrane oxygenation (ECMO), monitoring changes in cardiopulmonary function and early clinical interventions are crucial.

Conclusion

By weighing the beneficial and detrimental effects of the treatment, it calls for early diagnosis and new therapeutic strategies for the complication.

Robotic mitral valve surgery

Totally endoscopic robotic mitral valve repair is the least invasive surgical therapy for mitral valve disease. Robotic mitral valve surgery demonstrates faster recovery with shorter hospital stays, less morbidity, and equivalent mortality and mid-term durability compared to sternotomy. In this review, we will explore the advantages and disadvantages of robotic mitral valve surgery and consider important technical details of both operative set-up and mitral valve repair techniques. The number of robotic cardiac surgical procedures being performed globally is expected to continue to rise as experience grows with robotic techniques and increasing numbers of cardiac surgeons become proficient with this innovative technology. This will be facilitated by the introduction of newer robotic systems and increasing patient demand.

Unusual severe hypoxemia due to unilateral pulmonary edema after conventional cardiopulmonary bypass salvaged by veno-venous extracorporeal membrane oxygenation: a case report

BACKGROUND

We report a case in which veno-venous extracorporeal membrane oxygenation (V-V ECMO) saved the life of a patient who developed severe hypoxemia due to unusual unilateral pulmonary edema (UPE) after cardiopulmonary bypass (CPB).

CASE PRESENTATION

A 69-year-old man underwent aortic valve replacement and coronary artery bypass grafting. Following uneventful weaning off CPB, he developed severe hypoxemia. The ratio of arterial oxygen tension to inspired oxygen fraction (PaO2/FiO2) decreased from 301 mmHg 5 min after CPB to 42 mmHg 90 min after CPB. A chest X-ray revealed right-sided UPE. Immediately established V-V ECMO increased PaO2/FiO2 to 170 mmHg. Re-expansion pulmonary edema (REPE) was likely, as the right lung remained collapsed during CPB following the accidental opening of the right chest cavity during graft harvesting.

CONCLUSIONS

V-V ECMO was effective in improving oxygenation and saving the life of a patient who had fallen into unilateral REPE unusually developing after conventional CPB.

Propensity-matched analysis of robotic versus sternotomy approaches for mitral valve replacement

To compare early and medium-term outcomes between robotic and sternotomy approaches for mitral valve replacement (MVR). Clinical data of 1393 cases who underwent MVR between January 2014 and January 2023 were collected and stratified into robotic MVR (n = 186) and conventional sternotomy MVR (n = 1207) groups. The baseline data of the two groups of patients were corrected by the propensity score matching (PSM) method. After matching, the baseline characteristics were not significant different between the two groups (standardized mean difference < 10%). Moreover, the rates of operative mortality (P = 0.663), permanent stroke (P = 0.914), renal failure (P = 0.758), pneumonia (P = 0.722), and reoperation (P = 0.509) were not significantly different. Operation, CPB and cross-clamp time were shorter in the sternotomy group. On the other hand, ICU stay time, post-operative LOS, intraoperative transfusion, and intraoperative blood loss were shorter or less in the robot group. Operation, CPB, and cross-clamp time in robot group were all remarkably improved with experience. Finally, all-cause mortality (P = 0.633), redo mitral valve surgery (P = 0.739), and valve-related complications (P = 0.866) in 5 years of follow-up were not different between the two groups. Robotic MVR is safe, feasible, and reproducible for carefully selected patients with good operative outcomes and medium-term clinical outcomes.

Redefining Unilateral Pulmonary Edema after Mitral Valve Surgery on Chest X-ray Imaging Using the RALE Scoring System

Introduction: Unilateral pulmonary edema (UPE) is a potential complication after mitral valve surgery (MVS), and its cause is not yet fully understood. Definitions are inconsistent, and previous studies have reported wide variance in the incidence of UPE. This research aims at the evaluation of the Radiographic Assessment of Lung Edema (RALE) score concerning assessment of UPE after MVS in order to provide an accurate and consistent definition of this pathology. Methods and Results: Postoperative chest X-ray images of 676 patients after MVS (minimally invasive MVS, n = 434; conventional MVS, n = 242) were retrospectively analyzed concerning presence of UPE. UPE was diagnosed only after exclusion of other pathologies up until the eighth postoperative day. RALE values were calculated for each patient. ROC analysis was performed to assess diagnostic performance. UPE was diagnosed in 18 patients (2.8%). UPE occurred significantly more often in the MI-MVS group (p = 0.045; MI-MVS n = 15; C-MVS n = 3). Postoperative RALE values for the right hemithorax (Q1 + Q2) > 12 and the right-to-left RALE difference ((Q1 + Q2) - (Q3 + Q4)) > 13 provide a sensitivity of up to 100% and 94.4% and a specificity of up to 88.4% and 94.2% for UPE detection. Conclusion: The RALE score is a practical tool for assessment of chest X-ray images after MVS with regard to UPE and provides a clear definition of UPE. In addition, it enables objective comparability when assessing of the postoperative course. The given score thresholds provide a sensitivity and specificity of up to 94%. Further, UPE after MVS seems to be a rather rare pathology with an incidence of 2.6%.

Endoscopic Robotic Mitral Valve Surgery in Patients With Previous Sternotomy Cardiac Surgery

Objective: Mitral surgery is higher risk in patients with a previous median sternotomy. We describe an endoscopic robotic approach in this higher-risk cohort by an experienced robotic team. Methods: From January 2006 through June 2021, 152 consecutive patients with previous sternotomy cardiac surgery underwent mitral surgery using endoscopic robotics. Peripheral perfusion with endoaortic balloon occlusion was used in 148 patients (97.4%) and ventricular fibrillation in 4 patients (2.6%). Results: Mitral repair was performed in 73 patients (48%) including primary repair in 57 patients and re-repair in 16 patients, mitral replacement in 78 patients (51.3%) including primary replacement in 26 patients, conversion of a previous repair to replacement in 28 patients, and re-replacement in 24 patients. A paravalvular leak was primarily repaired in 1 patient (0.7%). Concomitant procedures included tricuspid repair in 28 patients (18.4%) and cryoablation in 8 patients (5.3%). Postoperative echocardiography in the mitral repair patients demonstrated none to mild regurgitation in 72 patients (98.6%). One repair patient (1.4%) had severe regurgitation and required robotic mitral replacement 5 days postoperatively. There were no paravalvular leaks in the mitral replacement patients. Operative mortality occurred in 3 patients (1.97%). Stroke occurred in 1 patient (0.7%), prolonged ventilation in 18 patients (11.8%), renal failure in 2 patients (1.4%), and re-exploration for bleeding in 10 patients (6.6%). Mean length of stay for the entire cohort was 5 ± 5.4 days. Conclusions: Robotic mitral valve surgery can be extended to patients with previous sternotomy with satisfactory efficacy and low operative mortality and morbidity.

Unilateral pulmonary oedema: a case report and literature review

Acute myocarditis is often secondary to an acute virus infection, which can be the first manifestation of upper respiratory tract symptoms, followed by chest tightness, shortness of breath, palpitations, chest pain and other non-specific symptoms. In severe cases, it can quickly progress to serious complications such as heart failure, shock and respiratory failure. Laboratory examinations can show an increase of myocardial injury markers, infection and inflammatory indicators. Cardiac ultrasound can detect the weakening of the myocardial contraction and valve regurgitation. On imaging, bilateral pulmonary oedema demonstrates symmetrical infiltration along the hilum of lung, called the “butterfly shadow”. This current case report describes a patient with unilateral pulmonary oedema caused by myocarditis that was initially misdiagnosed and treated as pneumonia. The patient was subsequently treated with the application of extracorporeal membrane oxygenation and he made a full recovery. A review of this case highlights that when a patient’s symptoms are not typical, a comprehensive examination and evaluation are required to avoid incorrect treatment.

Unilateral Pulmonary Edema after Minimally Invasive Cardiac Surgery: A Case Report

Unilateral pulmonary edema after minimally invasive cardiac surgery is a rare, but potentially life-threatening condition. However, the exact causes of unilateral pulmonary edema remain unclear. We experienced aggressive unilateral pulmonary edema followed by redo-resection of recurrent left atrial myxoma through a right mini-thoracotomy. Intraoperative veno-venous extracorporeal membrane oxygenation was applied after the termination of cardiopulmonary bypass, and separate mechanical ventilation using a double-lumen endotracheal tube was applied after surgery. The patient was successfully treated and discharged uneventfully.

Unilateral pulmonary oedema after minimally invasive and robotically assisted mitral valve surgery

OBJECTIVES

Unilateral pulmonary oedema (UPO) is a severe complication of minimally invasive cardiac surgery. UPO rates and UPO-related mortality vary considerably between different studies. Due to lack of consistent diagnostic criteria for UPO, the aim of this study was to create a reproducible radiological classification for UPO. Also, risk factors for UPO after robotic and minimally invasive mitral valve operations were evaluated.

METHODS

Two hundred and thirty-one patients who underwent elective minimally invasive mitral valve surgery between January 2009 and March 2017 were evaluated. Chest radiographs of the first postoperative morning were categorized into 3 UPO grades based on the severity of radiological signs of pulmonary oedema described in this study. The radiographs were analysed by 2 independent radiologists and interobserver agreement was evaluated. The clinical significance of the classification was evaluated by comparing postoperative PaO2/FiO2 values and total ventilation times between the different UPO grades. Also, multivariable logistic regression analysis was employed to identify risk factors for UPO.

RESULTS

Interobserver agreement was substantial (Kappa = 0.780). Median total ventilation times were significantly longer with increasing severity of UPO, 15 (interquartile range 12-18) h for no UPO, 18 (interquartile range 15-24) h for grade I UPO and 25 (interquartile range 21-31) h for grade II UPO. Pulmonary hypertension [adjusted odds ratios (AOR) 2.51, 95% confidence intervals (CI) 1.43-4.40; P = 0.001], moderate or severe heart failure (AOR 2.88, 95% CI 1.27-6.53; P = 0.011), body mass index (AOR 1.14, 95% CI 1.02-1.28; P = 0.017) and cardiopulmonary bypass time (AOR 1.02, 95% CI 1.01-1.03; P < 0.001) were identified as independent risk factors for UPO and robotic approach (AOR 0.27, 95% CI 0.12-0.62; P = 0.002) as protective against UPO.

CONCLUSIONS

Due to the variability of the diagnostic criteria for UPO in previous studies, a radiological classification for UPO is required to reliably assess the rates and risk factors for UPO. The radiological classification described in this study demonstrated high interobserver agreement and correlated with total ventilation times and postoperative PaO2/FiO2 values.

Unilateral Pulmonary Edema After Robotically Assisted Mitral Valve Repair Requiring Veno-Venous Extracorporeal Membrane Oxygenation

Unilateral pulmonary edema (UPE) is an uncommon yet potentially life-threatening complication of minimally invasive cardiac surgery (MICS). Most frequently described after robotically assisted mitral valve (MV) repair, it is characterized by right lung edema, hypoxemia, hypercapnia, pulmonary hypertension, and hemodynamic instability beginning minutes-to-hours after separation from cardiopulmonary bypass (CPB). The authors describe a severe case with refractory hypoxemia requiring veno-venous (VV) extracorporeal membrane oxygenation (ECMO) after robotically assisted MV repair.

Robotic mitral valve surgery: a review and tips for safely negotiating the learning curve

Totally endoscopic robotic mitral valve repair represents the least invasive surgical therapy for mitral valve disease. Comparative results for robotic mitral valve surgery against sternotomy are impressive, repeatedly demonstrating shorter hospital stay, faster return to normal activities, less morbidity and equivalent mortality and mid-term durability. We lack data comparing robotic approaches to totally endoscopic minimally invasive mitral valve surgery using 3D vision platforms. In this review, we explore the advantages and disadvantages of robotic mitral valve surgery and share technical tips that we have learned to help teams embarking on their robotic journey. We consider factors necessary for the successful implementation of a robotic programme including the importance of training a dedicated team, with the common goal to avoid any compromise in either patient safety or repair quality during the learning curve. As experience grows with robotic techniques and more cardiac surgeons become proficient with this innovative technology, the volume of robotic cardiac procedures around the world will increase helped by the introduction of new robotic systems and patient demand. Well informed patients will increasingly seek out the opportunity of robotic valve reconstruction in reference centres in the hands of a few highly experienced robotic surgeons.

Minimally invasive mitral valve surgery

There is considerable interest and demand in the application of minimally invasive techniques in cardiac surgery driven by multiple factors including patient cosmesis and satisfaction, reduction of surgical trauma and the development of specialized instrumentation that allows these procedures to be performed safely. Minimally invasive mitral valve surgery (MIMVS) has been conducted for more than 25 years and has been shown to offer multiple benefits including better cosmetic results, enhanced post-operative recovery, improved patient satisfaction and most importantly, equivalent clinical outcomes with regards to quality and safety when compared to the standard sternotomy approach. MIMVS may be particularly beneficial in certain subgroups of patients, for example patients undergoing redo mitral valve surgery. In this article, we discuss patient selection criteria for MIMVS, the merits and drawbacks of MIMVS relative to conventional sternotomy approaches, and detail procedural aspects including anaesthetic management, intraoperative technique, and important considerations in myocardial protection and cardiopulmonary bypass (CPB). When considering developing a MIMVS programme, as for any new technique, a team approach to the introduction of the programme is essential. Although it is clear that patient selection is important, particularly early in a surgical programme, with experience complex repairs can be performed through a minimally invasive approach with excellent outcomes.

Robotic-assisted cardiac surgery without lung isolation utilizing single-lumen endotracheal tube intubation

OBJECTIVES

This study assessed the feasibility and outcomes of performing robotic cardiac surgery without lung isolation using single-lumen (SL) endotracheal tube intubation.

METHODS

Between 2013 and 2017, 132 patients underwent robotically-assisted atrial septal defect closure. A retrospective analysis was performed of 23 patients (11 males, mean age 30.9 ± 5 years) who underwent robotic surgery with double-lumen (DL) endotracheal tube intubation (group 1) compared with 109 patients (57 males, mean age 32.4 ± 7.5 years) undergoing the same procedure with SL endotracheal intubation (group 2). The patient groups were compared in terms of demographic characteristics, operative data, and complications. The technical feasibility of the robotic procedure without lung isolation was evaluated.

RESULTS

There were no mortality, intraoperative complication, and conversion. Mean total anesthesia time was significantly decreased in the SL intubation group (238.3 ± 22.4 vs 227.2 ± 21.2 minutes; P = .025). First-pass intubation success was significantly higher in the SL intubation group (17 [73.9%] vs 98 [89.9%] patients; P = .032). Mean ventilation time (10.9 ± 5.3 hours), intensive care unit stay (16.8 ± 10.1 hours), and the length of hospital stay (3.8 ± 1.2 days) was significantly decreased in patients with SL tube (P < .05). Unilateral reexpansion pulmonary edema was observed in five (21.7%) patients with DL tube, whereas no patient with SL tube had this complication.

CONCLUSIONS

SL endotracheal tube intubation without lung isolation is a feasible and safe airway alternative in robotic cardiac procedures. This approach resulted in shorter anesthesia time, ventilation time and the length of hospital stay. Port placement and robotic set-up can be uneventfully performed without lung isolation.

Preventive Strategy for Reexpansion Pulmonary Edema After Minimally Invasive Cardiac Surgery

Reexpansion pulmonary edema is a serious complication of minimally invasive cardiac surgery through the right minithoracotomy. As reexpansion mechanical injury and ischemia reperfusion injury to the collapsed lung are possible mechanisms, we introduced a preventive protocol that consists of intermittent ventilation of the right lung, restoration of bilateral ventilation, administration of mannitol before unclamping the aorta, and institution of mild hypothermia. Among 469 patients who underwent minimally invasive cardiac surgery, we used this protocol in 379 patients. Reexpansion pulmonary edema incidence decreased significantly from 7.8% to 2.1% (P = .006). Although further evaluation is required, our protocol may be effective in preventing reexpansion pulmonary edema.

The successful use of extra-corporeal membrane oxygenation as rescue therapy for unilateral pulmonary edema following minimally invasive mitral valve surgery

Unilateral right pulmonary edema has been reported as a potential life-threatening complication after minimally invasive mitral valve surgery. Nearly 2% of these cases in the immediate postoperative period have been reported to require extra-corporeal membrane oxygenation support as a rescue therapy for severe hypoxia. The exact pathophysiology of this condition remains unclear, but has been assumed to be related to ischemia–reperfusion injury and re-expansion pulmonary edema. We present in this report the successful use of extra-corporeal membrane oxygenation to manage two cases of severe hypoxia and multiorgan dysfunction secondary to unilateral right pulmonary edema.

Port-Access Mitral Valve Surgery-An Evolution of Technique

Port-access mitral valve surgery has been around since 1995; and many variations upon the technique have been developed. Since 1996, we have performed more than 2500 port-access mitral valve surgeries, and thus gained a substantial experience. The purpose of this document is to describe the current status of port-access mitral surgery at 1 institution, and to share the "know how" and life lessons behind the patient selection and conduct of the operation to accomplish results similar to those achieved from sternotomy mitral valve surgery. While port access started in larger institutions, it can be performed in small centers with the proper guidance of the pearls and pitfalls of this operation, given to young surgeons regarding the right way to start a program.

Robotic mitral valve replacements with bioprosthetic valves in 52 patients: experience from a tertiary referral hospital

OBJECTIVES

Robotic mitral valve replacement (MVR) emerged in the late 1990s as an alternative approach to conventional sternotomy. With the increased use of bioprosthetic valves worldwide and strong patient desire for minimally invasive procedures, the safety and feasibility of robotic MVRs with bioprosthetic valves require investigation.

METHODS

Between January 2013 and May 2017, 52 consecutive patients underwent robotic MVRs using the da Vinci Si surgical system (Intuitive Surgical Inc., Sunnyvale, CA, USA). Their mean age was 55.1 ± 13.8 years, and mean EuroSCORE II was 2.25% ± 1.25%. Among the enrolled patients, 32 (61.5%) patients presented with preoperative atrial fibrillation, 6 (11.5%) patients had experienced embolic stroke and 5 (9.6%) patients had undergone previous cardiac surgery. The operations were performed using cardiopulmonary bypass (CPB) under an arrested heart status.

RESULTS

Five porcine valves and 47 bovine valves were implanted. A total of 38 (73.1%) patients received concomitant cardiac procedures, including 26 Cox-maze IV procedures, 12 tricuspid valve repairs and 5 atrial septal defect repairs. The mean aortic cross-clamp and CPB times were 141.3 ± 34.3 min and 217.1 ± 42.0 min, respectively. There was no operative mortality. During the mean follow-up of 29 ± 15 months, no prosthesis degeneration was noted. The average left atrial dimension exhibited a significant decrease from 51.4 ± 11.5 mm to 42.6 ± 10.1 mm.

CONCLUSIONS

Robotic MVR with bioprosthetic valves is safe, feasible and reproducible. Mid-term results are encouraging. Both aortic cross-clamp and CPB times can be improved with experience.

Minimal volume ventilation during robotically assisted mitral valve surgery

INTRODUCTION

A minimal volume ventilation method for robotically assisted mitral valve surgery is described in this study. In an attempt to reduce postoperative pulmonary dysfunction, 40 of 174 patients undergoing robotically assisted mitral valve surgery were ventilated with a small tidal volume during cardiopulmonary bypass.

METHODS

After propensity score matching, 31 patients with minimal volume ventilation were compared with 54 patients with no ventilation. Total ventilation time, PaO₂/FiO₂ ratio, arterial lactate concentration, and the rate of unilateral pulmonary edema in the matched minimal ventilation and standard treatment groups were evaluated.

RESULTS

Patients in the minimal ventilation group had shorter ventilation times, 12.0 (interquartile range: 9.9-15.0) versus 14.0 (interquartile range: 12.0-16.3) hours (p = 0.036), and lower postoperative arterial lactate levels, 0.99 (interquartile range: 0.81-1.39) versus 1.28 (interquartile range: 0.99-1.86) mmol/L (p = 0.01), in comparison to patients in the standard treatment group. There was no difference in postoperative PaO₂/FiO₂ ratio levels or in the rate of unilateral pulmonary edema between the groups.

CONCLUSION

Minimal ventilation appeared beneficial in terms of total ventilation time and blood lactatemia, while there was no improvement in arterial blood gas measurements or in the rate of unilateral pulmonary edema. The lower postoperative arterial lactate levels may suggest improved lung perfusion among patients in the minimal volume ventilation group. The differences in the ventilation times were in fact small, and further studies are required to confirm the possible advantages of the minimal volume ventilation method in robotically assisted cardiac surgery.