Anaesthetic implications of intra-operative Indocyanine Green use in pediatric surgery.

INTRODUCTION: The use of Indocyanine Green (ICG) dye for fluorescent guided surgery is increasing in children. In many cases, ICG is injected intravenously peri-operatively and is known to falsely alter peripheral oxygenation readings because of interference with the measured red/infrared absorbance ratio of pulsatile blood. METHODS: The study occurred at a single centre tertiary children's hospital. ICG was delivered peri-operatively. SpO2 was monitored real-time in all patients. Blood pressure, heart rate, expired carbon dioxide and electrocardiographic data were collected from anaesthetic records. Data is median (interquartile range) RESULTS: Twenty-five patients(13 F;12 M) age 60(77)months and weight 17(18.7)kg were included between 01/April/2021 and 31/Nov/2022. Fifteen patients received 0.5(0.38) mg/kg ICG at induction of anesthesia with ΔSpO2 of 6(2) %. Median time to ΔSpO2 fall was 25(6) s with recovery taking 74(68) s. Time to recovery and ΔSpO2 were proportional to ICG dose/kg with r2 of 0.7993 and 0.597 and p of 0.0008 and 0.001 respectively on linear regression. Five patients had intralesional ICG and one had an enteral dose with no effect on SpO2. Eight patients had a total of 20 intraoperative bolus doses of ICG with no effect on SpO2 in 11. In 9, time to SpO2 fall was 26(12) s with ΔSpO2 of 4(1) % and recovery at 24(50) s. No corrective anaesthetic manoeuvres were required. CONCLUSION: Understanding the timings of the transient artefactual fall and recovery in SpO2 following ICG injection is essential for safe anesthesia. This is the first study to evaluate this effect in children prospectively.

Assessment of jejunal interposition perfusion using indocyanine green.

INTRODUCTION: Jejunal interposition (JI) is an option for oesophageal replacement in children; ensuring good graft perfusion is essential. We report three cases where Indocyanine Green (ICG) with Near-Infrared Fluorescence (NIRF) was used to assess perfusion during graft selection, passage into the chest and anastomotic assessment. This extra assessment may reduce risk of anastomotic leak and/or stricture. METHODS: We describe the technique and salient features of all patients who have undergone ICG/NIRF-assisted JI in our centre. Patient demographics, indications for surgery, intra-operative plan, video of NIR perfusion assessment, complications and outcomes were reviewed. RESULTS: ICG/NIRF was used in three patients (2M:1F) at a dose of 0.2 mg/kg. ICG/NIRF imaging helped select the jejunal graft and confirmed perfusion after division of segmental arteries. Perfusion was assessed before and after passing the graft through the diaphragmatic hiatus and before and after making the oesophago-jejunal anastomosis. Intrathoracic assessment at the end of the procedure confirmed good perfusion of mesentery and intrathoracic bowel. In two patients, the reassurance contributed to successful procedures. In the third patient, graft selection was satisfactory, but borderline perfusion on clinical assessment after passing the graft to the chest, confirmed by ICG/NIRF meant the graft was abandoned. CONCLUSIONS: ICG/NIRF imaging was feasible and augmented our subjective assessment of graft perfusion, giving greater confidence during graft preparation, movement, and anastomosis. In addition, the imaging helped us abandon one graft. This series demonstrates the feasibility and benefit of ICG/NIR use in JI surgery. Further studies are required to optimise ICG use in this setting.

Fluorescence-guided lymph node sampling is feasible during up-front or delayed nephrectomy for Wilms tumor.

BACKGROUND: Lymph node sampling is critical to surgical staging in Wilms tumor; failure to sample lymph nodes is associated with under-staging and an increased incidence of local relapse. However, no standard lymphatic mapping method is currently being utilized for Wilms tumor to aid identification of regional draining lymph nodes. Herein, we describe the use of fluorescence-guided lymphatic mapping for Wilms tumor. MATERIALS AND METHODS: Two tertiary level referral centers independently began indocyanine green (ICG) fluorescence-guided nodal mapping. In one center, this was achieved with ipsilateral intra-parenchymal (IP) injection of ICG during minimally invasive tumor nephrectomy (MIN) following neoadjuvant chemotherapy and in the other, with Peri­Hilar (PH) injection during upfront, open tumor nephrectomy (ON). Successful lymph node mapping was defined as the presence of fluorescence signal in draining lymph nodes. RESULTS: Eight patients (median age of 2.5 years) underwent fluorescence-guided lymphatic mapping (four IP and four PH injection). Lymphatic mapping was successful in seven patients (88%) including each of the four patients with IP injection. CONCLUSIONS: Fluorescence-guided lymphatic mapping of Wilms tumor drainage is feasible by both IP injection and PH injection techniques. However, whether lymphatic mapping improves the precision of lymph node sampling is unknown and should be studied in prospective trials.

A single centre experience using internal traction sutures in managing long gap oesophageal atresia.

AIM: Thoracoscopically placed internal traction sutures (ITS) for the initial management of long gap oesophageal atresia (LGOA), not amenable to primary anastomosis, was first described in 2015. Here we describe our experience using ITS both thoracoscopically and at thoracotomy where the gap between upper and lower oesophagus is too wide for primary anastomosis. METHOD: The case notes of all infants treated with ITS for oesophageal atresia (01/10/2015 to 01/12/2019) were reviewed. Gaps considered too wide for an anastomosis had ITS placed between the two pouches as described by Patkowski in 2015. All patients were gastrostomy fed.  Patients returned to theatre with an expectation to complete the anastomosis or re-tighten the traction sutures. RESULTS: Seven patients (4 OA, 1 OA with proximal fistula, 2 OA/distal TOF) median birthweight 2.28 kg (1.2-3.6 kg) were managed using ITS. Median gap length 4.5 (3-9) vertebral bodies.  ITS were placed thoracoscopically in 5 cases and at thoracotomy in 2 at median 46 days (1-120) old. In all cases, ITS was associated with significant intra-thoracic adhesions. Five patients leaked from the traction sutures. Four patients had a delayed primary anastomosis performed at thoracotomy and 3 required a cervical oesophagostomy. The median length of stay was 159 days (98-282).  All patients started thoracoscopically eventually required thoracotomy. CONCLUSION: The use of ITS in our department was associated with significant complications, particularly intra-thoracic leaks and adhesions.  In our hands ITS did not improve the feasibility of thoracoscopic repair for LGOA and has been abandoned by us. LEVEL OF EVIDENCE: Level IV Case Series.

Fluorescent Guided Lymph Node Harvest in Laparoscopic Wilms Nephroureterectomy.

Lymph node harvest is an integral part of Wilms tumor surgery with both SIOP and COG protocols asking for more than 6 lymph nodes to best evaluate for nodal spread and a subsequent need for intensification of treatment. The majority of studies show that in both open and minimally invasive resections the median number of nodes removed is 4. Indocyanine green and near infrared fluorescence may be the key to solving this problem. In adult gynaecology, colorectal and breast cancers, ICG is used to identify sentinel nodes and facilitate nodal retrieval. This report describes its use in Wilms tumor as a technique to aid lymph node harvest.

3D Model Facilitated Zero-Ischemia Laparoscopic Nephron Sparing Resection in Nephroblastomatosis Following the Addition of Cis-Retinoic Acid.

There are limited reports of laparoscopic nephron sparing surgery (LNSS) in children and none where a 3D model facilitated oncological resection. There are also limited reports discussing the use of cis-retinoic acid in bilateral diffuse hyperplastic perilobar nephrogenic rests (DHPLNR). We report the first case of a 3D model facilitated zero-ischemia LNSS in children and the first following treatment with cis-retinoic acid. The patient was a 3-year-old girl with bilateral DHPLNR who had recurrent disease following standard therapy. She had suspicious lesions in the upper pole of the left kidney. Both were completely excised and histologically described as hyperplastic nephrogenic rests.

Paediatric laparoscopic Heller's cardiomyotomy: a single centre series.

BACKGROUND: The optimal management of oesophageal achalasia remains unclear in the paediatric population due to the rarity of the disease. This study reviews the institutional experience of the laparoscopic Heller's cardiomyotomy (HC) procedure and attempts to define the most appropriate treatment. METHODS: A retrospective review of children undergoing HC at a single institution was performed. Demographics, pre-operative investigations, and interventions were reviewed. Post-operative outcomes and follow up were evaluated. Data is expressed as median (range). RESULTS: Twenty-eight children were included (13 male, 15 female) whose median age was 13 (3.2-17.4) years. Nine children underwent a pre-operative oesophageal balloon dilatation (OBD) a median of 1(1-6) times. Others included botulinum toxin injection (n=1) and Nifedipine (n=1). All had a pre-operative upper gastrointestinal contrast series, and twenty-five had upper gastrointestinal endoscopy and manometry. All had laparoscopic HC with no conversions, and ten had a concomitant fundoplication. Post-operative intervention occurred in eight (28%) incorporating OBD (n=7), of whom four required a redo HC. One patient underwent a redo without intervening OBD. Follow-up was for a median of 0.83 (0-5) years with fourteen children discharged from surgical follow-up. Twenty-seven have thus far had a good outcome. CONCLUSION: This study comprises the largest series of paediatric laparoscopic HC reported to date. It is effective with or without a fundoplication and is the best long term treatment modality available. OBD for persisting symptoms following HC may obviate the need for redo myotomy.