Bronchoscopic Indocyanine Green Fluorescence Imaging of the Anastomotic Perfusion After Tracheal Surgery

Management of Primary Tracheal Tumors

The diagnosis and treatment of patients with tracheal tumors is challenging due to the low incidence of these tumors. A precise diagnostic work-up and experience is necessary to distinguish between patients amenable to surgery and nonsurgical patients. An individualized treatment concept should be established for each patient in a multidisciplinary team and ranges from interventional removal of benign lesions to multimodal strategies in patients with extended malignant tumors. Early diagnosis despite unspecific symptoms and complete resection are crucially important to achieve long-term survival.

[Paediatric Airway Surgery - Indications and Techniques]

Even in specialised centres, surgical procedures on the airway are only rarely performed in paediatric patients. Moreover, knowledge of various specific anatomical characteristics, diseases and surgical techniques is a prerequisite to treat these patients. Most commonly, sequelae of long-term intubation or tracheostomy in multimorbid patients necessitate surgical repair. Moreover, congenital malformations of the airways might require surgical interventions. However, these are commonly associated with other organ malformations, which adds further complexity to the treatment concept. Thus, cooperation within an interdisciplinary team is absolutely necessary to treat these patients. However, good postoperative outcomes after paediatric airway surgery can be achieved in experienced centres with an appropriate infrastructure. Specifically, this means long-term tracheostomy-free survival with preserved laryngeal functions in most of the patients. This review provides a summary of common indications and surgical techniques in paediatric airway surgery.

Application of indocyanine green in surgery: A review of current evidence and implementation in trauma patients

Background: Modern surgical medicine strives to manage trauma while improving outcomes using functional imaging. Identification of viable tissues is crucial for the surgical management of polytrauma and burn patients presenting with soft tissue and hollow viscus injuries. Bowel anastomosis after trauma-related resection is associated with a high rate of leakage. The ability of the surgeon’s bare eye to determine bowel viability remains limited, and the need for a more standardized objective assessment has not yet been fulfilled. Hence, there is a need for more precise diagnostic tools to enhance surgical evaluation and visualization to aid early diagnosis and timely management to minimize trauma-associated complications. Indocyanine green (ICG) coupled with fluorescence angiography is a potential solution for this problem. ICG is a fluorescent dye that responds to near-infrared irradiation. Methods: We conducted a narrative review to address the utility of ICG in the surgical management of patients with trauma as well as elective surgery. Discussion: ICG has many applications in different medical fields and has recently become an important clinical indicator for surgical guidance. However, there is a paucity of information regarding the use of this technology to treat traumas. Recently, angiography with ICG has been introduced in clinical practice to visualize and quantify organ perfusion under several conditions, leading to fewer cases of anastomotic insufficiency. This has great potential to bridge this gap and enhance the clinical outcomes of surgery and patient safety. However, there is no consensus on the ideal dose, time, and manner of administration nor the indications that ICG provides a genuine advantage through greater safety in trauma surgical settings. Conclusions: There is a scarcity of publications describing the use of ICG in trauma patients as a potentially useful strategy to facilitate intraoperative decisions and to limit the extent of surgical resection. This review will improve our understanding of the utility of intraoperative ICG fluorescence in guiding and assisting trauma surgeons to deal with the intraoperative challenges and thus improve the patients’ operative care and safety in the field of trauma surgery.

Pädiatrische Atemwegschirurgie: Indikationen und Techniken

In der pädiatrischen Atemwegschirurgie sind zahlreiche anatomische Besonderheiten, spezifische Krankheitsbilder sowie spezielle Operationstechniken zu beachten. Auch an spezialisierten Zentren sind diese Eingriffe bei pädiatrischen Patienten eher selten. Ätiologisch handelt es sich meist um erworbene Stenosen als Folge von Frühgeburtlichkeit, Langzeitintubation oder -tracheotomie, welche typischerweise in Kindern mit zahlreichen Komorbiditäten auftreten. Kongenitale Fehlbildungen der Atemwege gehen häufig mit weiteren Malformationen einher, welche die erfolgreiche Behandlung zusätzlich erschweren. Voraussetzung zur Behandlung dieser Kinder sollte daher ein multidisziplinäres Team sein. An erfahrenen Zentren mit entsprechender Infrastruktur kann die chirurgische Behandlung dieser Kinder mit sehr guten Ergebnissen durchgeführt werden. So wird bei den meisten Patienten nach chirurgischer Behandlung eine sehr gute Lebensqualität ohne Notwendigkeit einer Langzeittracheostomie erreicht. Diese Übersichtsarbeit fasst die wichtigsten Indikationen, sowie die häufigsten Operationstechniken in der pädiatrischen Atemwegschirurgie zusammen.

Rapid intraoperative perfusion assessment of parathyroid adenomas with ICG using a wide-field portable hand-held fluorescence imaging system

BACKGROUND

Fluorescence angiography (FA) using indocyanine green dye (ICG) has recently been introduced for real-time identification of parathyroid adenomas. However, time to peak fluorescence has not yet been critically evaluated.

METHODS

This was a retrospective review of parathyroidectomies with ICG FA over a one-year period.

RESULTS

There were 66 patients with average age of 64 years. The average time to initial fluorescence was 26.7 s and to peak fluorescence was 38.0 s. The time to saline flush administration significantly correlated with times to initial and peak fluorescence (p < .0001). The rate of in-situ fluorescence was 97%. The rates of suspected adenoma detection were 69% for sestamibi scan, 71% for ultrasound, and 96% for CT scan. Imaging was discordant in 13 cases (20%), with the adenoma located on the opposite side of the neck in 4 cases.

CONCLUSIONS

ICG FA is a rapid and effective adjunct for the intraoperative identification of parathyroid adenomas.

Single running suture technique is associated with low rate of bronchial complications after lung transplantation

BACKGROUND

Lung transplantation has evolved to a routinely performed surgical procedure in patients with end-stage pulmonary disease. Bronchial healing problems are rare but represent a potential life-threatening complication. Herein, we aimed to define the incidence, classification, and treatment of bronchial complications after lung transplantation.

MATERIAL AND METHODS

All patients receiving lung transplantation between January 1999 and December 2017 were included in this retrospective study. All bronchial anastomoses were performed in a standardized technique using a single, polydioxanone running suture. The rate of anastomotic complications requiring an intervention, type of complication according the 2018 International Society for Heart and Lung Transplantation classification, and the clinical management were retrospectively analyzed.

RESULTS

A total of 2941 anastomoses were performed in 1555 patients. The overall incidence of relevant anastomotic complications was 1.56%, 0.68% for left anastomoses, and 2.44% for right anastomoses. In 6 patients, a surgical revision or retransplantation was performed, whereas endoscopic treatment alone was sufficient in 39 patients. One patient underwent right-sided retransplantation 6 months after the first lung transplantation after failed endoscopic treatment attempts. International Society for Heart and Lung Transplantation grade "S Lc Ec" was the most common type of anastomotic complication. The overall incidence decreased within the study period from 2.4% in the era 1999 to 2003 to 0.8% in the era 2014 to 2017. We found no significant difference in overall survival of patients with and without anastomotic complications (P = .995; hazard ratio, 0.99; 95% confidence interval, 0.63-1.58).

CONCLUSIONS

The single running suture technique is associated with a very low rate of true anastomotic complications. Close follow-up and early endoscopic treatment of patients with anastomotic complications result in excellent long-term outcomes.

Recent fluorescence imaging technology applications of indocyanine green in general thoracic surgery

Thoracic surgeons perform a wide variety of cancer operations, which are often associated with high morbidity and mortality. Thus, thoracic surgery involves many special challenges that require innovative solutions. The increased utilization of minimally invasive practices, poor overall cancer survival, and significant morbidity of critical operations remain key obstacles to overcome. Fluorescence imaging technology (FIT), involving the implementation of fluorescent dyes and imaging systems, is currently used as an adjunct for general thoracic surgery in many situations and includes sentinel lymph node mapping, pulmonary intersegmental plane identification, pulmonary nodule identification, pulmonary bullous lesion detection, evaluation of the anastomotic perfusion after tracheal surgery, and thoracic duct imaging for postoperative chylothorax. This technology enhances the surgeon's ability to perform operations, and has specific advantages. We review some of the key studies that demonstrate the applications of FIT in the field of general thoracic surgery, focusing on the use of indocyanine green.

Carinal resection

Tracheobronchial tumors with involvement of the carina represent a challenging problem in the pulmonary surgery. Carinal resection is referred to removal and reconstruction of the airway itself, whereas concomitant removal of the lung parenchyma (usually a whole lung) is termed as carinal pneumonectomy. Thorough preoperative workup of these patients is mandatory. Meticulous surgical technique and aggressive postoperative management is required for the best outcomes in these difficult cases. In the paper authors review surgical technique, evaluation and management of this challenging patient population.

Infrared intraoperative fluorescence imaging using indocyanine green in thoracic surgery

Thoracic surgery faces many unique challenges that require innovative solutions. The increase in utilization of minimally invasive practices, poor overall cancer survival and significant morbidity of key operations remain key obstacles to overcome. Intraoperative fluorescence imaging is a process by which fluorescent dyes and imaging systems are used as adjuncts for surgeons in the operating room. Other surgical subspecialists have shown that intraoperative fluorescence imaging can be applied as a practical adjunct to their practices. Thoracic surgeons over the last 15 years have also used intraoperative fluorescence imaging for sentinel lymph node mapping, lung mapping, oesophageal conduit vascular perfusion and lung nodule identification. This review describes some of the key studies that demonstrate the applications of intraoperative near-infrared fluorescence imaging.

Near-infrared intraoperative imaging for minimally invasive pulmonary metastasectomy for sarcomas

BACKGROUND

Complete pulmonary metastasectomy for sarcoma metastases provides patients an opportunity for long-term survival and possible cure. Intraoperative localization of preoperatively identified metastases and identification of occult lesions can be challenging. In this trial, we evaluated the efficacy of near-infrared (NIR) intraoperative imaging using second window indocyanine green during metastasectomy to identify known metastases and to detect occult nodules.

METHODS

Thirty patients with pulmonary nodules suspicious for sarcoma metastases were enrolled in an open-label, feasibility study (NCT02280954). All patients received intravenous indocyanine green (5 mg/kg) 24 hours before metastasectomy. Patients 1 through 10 (cohort 1) underwent metastasectomy via thoracotomy to assess fluorescence patterns of nodules detected by traditional methods (preoperative imaging and intraoperative visualization/bimanual palpation). After confirming reliability within cohort 1, patients 11 through 30 (cohort 2) underwent video-assisted thoracic surgery metastasectomy with NIR imaging.

RESULTS

In cohort 1, 14 out of 16 preoperatively identified pulmonary metastases (87.5%) displayed tumor fluorescence. Nonfluorescent metastases were deeper than fluorescent metastases (2.1 cm vs 1.3 cm; P = .03). Five out of 5 metastases identified during thoracotomy displayed fluorescence. NIR imaging identified 3 additional occult lesions in this cohort. In cohort 2, 33 out of 37 known pulmonary metastases (89.1%) displayed fluorescence. Nonfluorescent tumors were deeper than 2.0 cm (P = .007). NIR imaging identified 24 additional occult lesions. Of 24 occult lesions, 21 (87.5%) were confirmed metastases and the remaining 3 nodules were lymphoid aggregates.

CONCLUSIONS

NIR intraoperative imaging with indocyanine green (5 mg/kg and 24 hours before surgery) localizes known sarcoma pulmonary metastases and identifies otherwise occult lesions. This approach may be a useful intraoperative adjunct to improve metastasectomy.

Indocyanine green fluorescence/thermography evaluation of intercostal muscle flap vascularization

Background

During anatomical lung resection in high‐risk patients, the bronchial stump is covered with tissue flaps (e.g. pericardial fat tissue and intercostal muscle) to prevent bronchopleural fistula development. This is vital for reliable reinforcement of the bronchial stump. We evaluated the blood supply of the flap using indocyanine green fluorescence (ICG‐FL) and thermography intraoperatively in 27 patients at high risk for developing a bronchopleural fistula.

Methods

Before reinforcing the stump with a flap, the fluorescence agent was intravenously injected and the blood supply was evaluated. The surface temperature of the flap was measured with thermography. The two modalities were then compared.

Results

ICG‐FL intensity and surface temperature on the distal compared to the proximal side of the flap decreased by 32.6 ± 29.4% (P < 0.0001) and 3.5 ± 2.0°C (P < 0.0001), respectively. In patients with a higher ICG‐FL intensity value at the tip than the median, the surface temperature at the tip decreased by 2.7 ± 1.7°C compared to the proximal side. In patients with a lower ICG‐FL value at the tip, the surface temperature decreased by 4.6 ± 1.7°C (P = 0.0574). The bronchial stump reinforced the part of the flap with adequate blood supply; none of the patients developed a bronchopleural fistula.

Conclusions

ICG‐FL confirmed variation in the blood supply of the intercostal muscle flap, even if prepared using the same surgical procedure. Thermography analysis tends to correlate with the fluorescence method, but may be influenced by the state of flap preservation during surgery.