Robotic Anatomical Pulmonary Resections: An Australian Experience.

BACKGROUND: Robotic thoracic surgery is a minimally invasive technique that allows the surgeon to perform delicate, accurate surgical manoeuvres within the chest cavity without rib spreading. Previous studies have suggested potential benefits of the robotic platform in nodal upstaging due to its versatility, seven degrees of freedom of movement, and superior vision. However, there is currently a paucity of robust clinical data from Australia. AIMS: This study aimed to assess the perioperative safety and oncological efficacy of anatomical pulmonary resections performed using the robotic platform. Endpoints included mortality and major morbidity outcomes according to Clavien-Dindo classification and rate of pathological nodal upstaging compared with preoperative imaging using positron emission tomography. METHODS: A single-surgeon retrospective analysis was performed using data collected from two institutions from July 2021 to May 2022, after ethics committee approval. Consecutive patients who underwent anatomical robotic resections were included in the study, with subsequent analysis of patients who had confirmed primary lung cancer. RESULTS: A total of 52 patients underwent robotic anatomical pulmonary resection during the study period. Safety was demonstrated by 0% mortality and a 9.6% major complication rate, which was related to chest tube insertion for prolonged air leak or intensive care unit monitoring during treatment of atrial arrhythmia. After excluding patients who did not have primary lung cancer, 48 patients remained for further analysis; pathological nodal upstaging was observed in nine (18.8%) of these patients. On multivariate analysis, the total number of lymph nodes harvested was found to be a statistically significant predictor of nodal upstaging. Complete microscopic resection (R0) was achieved in 100% of patients. CONCLUSIONS: This study represents the most extensive documentation of robotic thoracic procedures in Australia in the existing literature. It demonstrated a satisfactory safety profile with a relatively high rate of nodal upstaging, possibly reflecting the ability of the robotic instruments to perform comprehensive and complete nodal resection at the time of anatomical pulmonary resection.

Novel Epicardial Access Technique Facilitated by Carbon Dioxide Insufflation of the Pericardium for Ablation of Ventricular Arrhythmias: Lessons From the Early Experience From a Single Centre in Australia.

INTRODUCTION: Epicardial access for mapping and ablation of the epicardial substrate may be required in catheter ablation of ventricular tachycardias (VT). However, high complication rates are associated with the standard epicardial access approach. Recently, a novel method of intentional coronary vein (CV) exit with pericardial CO2 insufflation to facilitate epicardial access has been described. This study describes our initial experience with this technique. METHODS: Patients undergoing epicardial VT ablation between 1 February 2021 to 31 May 2022 at the Royal Prince Alfred Hospital, Sydney, NSW, were included in this study. Via femoral venous access, a branch of the coronary sinus was sub-selected and intentional CV exit was performed with a high tip load coronary angioplasty wire. A microcatheter was then advanced over the wire into the pericardial space, followed by pericardial CO2 insufflation, facilitating subxiphoid pericardial puncture. RESULTS: Five (5) patients underwent epicardial access for VT mapping and ablation. All patients had successful intentional CV exit and CO2 facilitated epicardial access. The mean time to successful epicardial access was 37.2±17.5 minutes. With increasing operator experience, there was improvement in epicardial access times, with the fifth case requiring only 13 minutes. There was one case of inadvertent right ventricular puncture (without haemodynamic or ventilatory compromise) due to inappropriate CO2 insufflation into the right ventricle. Epicardial access was successful on the second attempt. CONCLUSION: This is the first case series of epicardial access facilitated by CO2 insufflation in Australia. This technique enabled successful epicardial access in all patients in our early experience, with no adverse outcomes from epicardial access. With increasing operator experience, this technique may allow for more widespread adoption of up-front epicardial access for the treatment of VT.

COVID-19 safety: aerosol-generating procedures and cardiothoracic surgery and anaesthesia - Australian and New Zealand consensus statement.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a contagious disease that is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Health care workers are at risk of infection from aerosolisation of respiratory secretions, droplet and contact spread. There are a number of procedures that represent a high risk of aerosol generation during cardiothoracic surgery. It is important that adequate training, equipment and procedures are in place to reduce that risk. RECOMMENDATIONS: We provide a number of key recommendations, which reduce the risk of aerosol generation during cardiothoracic surgery and help protect patients and staff. These include general measures such as patient risk stratification, appropriate use of personal protective equipment, consideration to delay surgery in positive patients, and careful attention to theatre planning and preparation. There are also recommended procedural interventions during airway management, transoesophageal echocardiography, cardiopulmonary bypass, chest drain management and specific cardiothoracic surgical procedures. Controversies exist regarding the management of low risk patients undergoing procedures at high risk of aerosol generation, and recommendations for these patients will change depending on the regional prevalence, risk of community transmission and the potential for asymptomatic patients attending for these procedures. CHANGES IN MANAGEMENT AS A RESULT OF THIS STATEMENT: This statement reflects changes in management based on expert opinion, national guidelines and available evidence. Our knowledge with regard to COVID-19 continues to evolve and with this, guidance may change and develop. Our colleagues are urged to follow national guidelines and institutional recommendations regarding best practices to protect their patients and themselves. ENDORSED BY: Australian and New Zealand Society of Cardiac and Thoracic Surgeons and the Anaesthetic Continuing Education Cardiac Thoracic Vascular and Perfusion Special Interest Group.

Early Outcomes After Mitral Valve Repair versus Replacement in the Elderly: A Propensity Matched Analysis.

BACKGROUND: To compare early outcomes of mitral valve repair versus replacement in elderly patients with degenerative mitral valve disease. METHODS: A retrospective review of prospectively collected clinical data of patients over 75 years of age, who underwent mitral valve surgery for degenerative disease, between 2010 and 2013, was carried out. Those undergoing mitral valve repair and replacement were propensity matched to adjust for baseline clinical differences. RESULTS: A total 260 patients were identified: mitral valve repair was undertaken in 145 and replacement in 115 patients. After propensity matching, 78 patients were included in each group. In the entire, unmatched population, in-hospital mortality was significantly higher in those undergoing replacement compared with those undergoing repair (9.6% vs 1.4%, p=0.003). In-hospital death occurred in six (7.7%) of the propensity matched replacement group and none in the repair group (p=0.012). Amongst the propensity matched groups, probability of survival at 1, 2 and 3 years were 0.94, 0.90 and 0.86 respectively for the repair group and 0.85, 0.77 and 0.69 for the replacement group: the HR for death between replacement and repair is 2.5 (1.2-5.4), p=0.012. CONCLUSIONS: Within the limitations imposed by retrospective analyses, our study demonstrates that, in elderly patients with degenerative disease of the mitral valve, repair is associated with improved short-term and mid-term outcomes compared with mitral valve replacement.

Intubated Versus Nonintubated General Anesthesia for Video-Assisted Thoracoscopic Surgery-A Case-Control Study.

OBJECTIVE: General anesthesia with endobronchial intubation and one-lung positive-pressure ventilation always has been considered mandatory for thoracic surgery. Recently, there has been interest in nonintubated techniques for video-assisted thoracoscopic surgery (VATS) in awake and sedated patients. The authors' center developed a nonintubated technique with spontaneous ventilation with the patient under general anesthesia using a supraglottic airway device. The authors believe that this was the first study to compare a nonintubated general anesthetic technique with an intubated general anesthetic technique for VATS. DESIGN: Retrospective, observational study. SETTING: Specialist cardiothoracic hospital in the United Kingdom. PARTICIPANTS: All patients who underwent elective minor VATS over 8 months (n = 73). INTERVENTIONS: A nonintubated general anesthetic technique with spontaneous ventilation via a supraglottic airway device was used for minor VATS procedures. This was compared with a case-matched intubated group. MEASUREMENTS AND MAIN RESULTS: Both groups had comparable baseline characteristics and surgical procedures. The anesthetic time was shorter in the nonintubated group (13.6±8.3 v 24.1±10.9 minutes, p<0.001). Surgical operating time and feasibility were similar. Intraoperatively, there were increases in end-tidal carbon dioxide (59.1±12.9 v 41.8±4.6, p<0.001) and respiratory rate (17.8±5.6 v 13.5±2.0, p<0.001) in the nonintubated group. Fewer patients in the nonintubated group had moderate-severe pain during recovery (19.4% v 48.4%, p = 0.02) and pain on discharge to the ward (25.8% v 61.3%, p = 0.004). There was a trend toward shorter recovery times, reduced oxygen requirement, and shorter hospital stays in the nonintubated group. CONCLUSIONS: A nonintubated general anesthetic technique is a feasible alternative to intubated general anesthesia for minor VATS procedures.

Anaesthetic considerations for non-intubated thoracic surgery.

General anaesthesia with intubation and single lung ventilation has always been considered essential for thoracic surgery. Over the last decade there has been a huge evolution in thoracic surgery with the development of multiport and uniportal minimally invasive techniques. The development of a non-intubated technique during which thoracic surgery is performed on patients who are spontaneously ventilating awake, under minimal sedation with the aid of local or regional anaesthesia or under general anaesthesia with a supraglottic airway device is winning acceptance as a valid alternative technique. The concept is to allow the creation of a spontaneous pneumothorax as the surgeon enters the chest. This can provide excellent lung isolation without the need for positive pressure ventilation on the dependant lung. Awake and minimal sedation techniques, which avoid the need for general anaesthesia, maintain a more physiological cardiopulmonary and neurological status and avoid postoperative nausea and vomiting. However, general anaesthesia with a supraglottic airway device is the technique that provides a more stable airway and facilitates oxygenation in cases where an unexpected conversion to open thoracotomy in needed. For non-intubated thoracic surgery a regional analgesic technique is essential; nonetheless a 'multimodal' approach to analgesia is recommended. Non-intubated anaesthetic techniques for thoracic surgery are innovative and exciting and drive to reduce the invasiveness of the procedures. We recommend that centres starting out with non-intubated techniques begin by performing minor video-assisted thoracic surgery (VATS) procedures in selected low risk patients. Early elective conversion should be employed in any unexpected surgical difficulty or cardiopulmonary problem during the learning curve to reduce the risk of emergency conversion and complications. Further research is needed to establish which patients benefit more from the technique and what is the real impact on perioperative mortality and morbidity.

Hydrogen ion concentration and coronary artery bypass graft surgery with and without cardiopulmonary bypass.

BACKGROUND: Acidosis during cardiopulmonary bypass (CPB) has been related to the strong ion difference (SID) and the composition of intravascular fluids that are administered. Less intravascular fluids tend to be administered during off- than on-pump CABG and should influence the degree of acidosis that develops. This study aimed to explore the role of CPB in the development of acidosis by comparing changes in hydrogen ion concentration ([H+]) and electrolytes in patients undergoing on- and off-pump coronary artery bypass graft (CABG) surgery. METHODS: Eighty two patients had arterial blood gas measurements pre-operatively, following CABG and at approximately 0600 h the morning after surgery. Carbon dioxide tension (PaCO2) and concentrations of sodium, potassium, chloride, [H+], bicarbonate and haemoglobin were measured and strong ion difference calculated. Data was analysed using mixed repeated-measures analysis of variance. RESULTS: Intra-operatively, mean SID decreased more in the on- compared to the off-pump group (4.0 mmol/L, 95% confidence interval 2.8-5.3 mmol/L, p < 0.001). Neither [H+] or PaCO2 changed significantly and there were no significant difference between the groups. By the morning following surgery, [H+] and PaCO2 had both increased (p < 0.001) and difference in SID had disappeared (p = 0.17). CONCLUSION: Despite significant differences in changes in SID, there were no differences in [H+] between patients during or after CABG surgery whether performed on- or off-pump. This may be have been the result of greater haemodilution in the on- compared to the off-pump group, compensating for change in SID by reducing the concentration of weak acids. Although it was associated with significantly greater decrease in SID, CPB was not associated with any significant increased risk of acidosis.