Innovative Off-label Use of Hysterosalpingography Catheter for Complete Lung Isolation in a Child with Left Lung Hydatid Cyst

The Editor, We report the case of a 4-year-old male child with hydatid cyst in the left lower lobe of the lung, who was scheduled to undergo thoracoscopic excision. Complete lung isolation was achieved by the use of a 5 French hysterosalpingography (HSG) catheter [Figure 1] in the left bronchus and right main stem bronchus intubation. In this case, the HSG catheter used, was noted to be safe, atraumatic (made of polyurethane, latex- free balloon) and an economically available alternative to the existing non- ubiquitous Paediatric bronchial blockers. A 4-year-old male child, weighing 12 kg, presented with a history of fever and cough for the past 8 months, with a sudden onset of difficulty in breathing for 4 days. Computed tomography of the thorax revealed a 53 mm × 43 mm well-circumscribed, thin-walled, hypodense cystic lesion in the lower lobe of the left lung. There was tracheal deviation as the lesion originated from the lateral wall of the chest. He was empirically treated with antibiotics and antihelminthic medications with suspicion of hydatid cyst or infected congenital pulmonary airway malformation. Enzyme-linked immunosorbent assay testing of cyst fluid for Echinococcus immunoglobulin G (IgG) was inconclusive. Preoperative evaluation showed decreased breath sounds on auscultation in the left lower lobe. Blood picture revealed leucocytosis with eosinophilia. He was scheduled for thoracoscopic cyst excision under general anaesthesia. After confirming adequate fasting and parental consent, patient was premedicated with intravenous (IV) 0.1 mg/ kg of midazolam. Nebulisation with budecort and salbutamol was given. The child was shifted to the operating room, with standard American Society of Anaesthesiology monitor, IV induction with propofol 2 mg/kg, fentanyl 2 μg/kg and atracurium 0.5 mg/kg was administered along with IV dexamethasone 0.1mg/kg. After preoxygenation, using Macintosh blade size 2, a 5 Fr HSG catheter was inserted in to the left main bronchus by manoeuvring the catheter tip 90° to the left after crossing the glottis, using a 0°, 3.5 sized Storz ventilating rigid bronchoscope, turning the head towards right side and the position of the catheter was confirmed [Figure 2] and fixed to the angle of mouth. The balloon was inflated with 1 mL of saline under direct vision. Then, the right main stem bronchus was intubated using a 4 mm microcuff endotracheal tube under direct laryngoscopy in parallel to the catheter. Both the HSG catheter and the microcuffed tube were secured in the first attempt and fixed together. Adequate lung isolation was confirmed by auscultation and lung ultrasonogram.[1] [Figure 3]. Depth of anaesthesia maintained using oxygen/air (FIO2 -0.6), isoflurane, bolus doses of time-bound atracurium at 0.2 mg/kg slow injection (more than 75 s) of low-dose atracurium was safe to use without any adverse events.[2] Pressure-controlled ventilation (Vte-5–6 ml/kg/RR-26 cycles/min) with permissive hypercarbia up to 50 mm Hg was allowed as per protocol. No episode of desaturation of <94% was documented. The child was operated in the right lateral position, with thoracoscopic excision under complete lung isolation. The cyst was marsupialised, and 3% sodium chloride irrigation was done to prevent recurrence of hydatid cyst, after confirming intraoperatively. Injection hydrocortisone 4 mg/kg was given. After the completion of surgery, the child was positioned supine, and HSG catheter was removed after deflation. The endotracheal tube was withdrawn to the carina, and recruitment breaths were provided to ensure left lung ventilation. Blood gas analysis was done after lung isolation and before extubation. Lung ultrasound confirmed adequate left lung expansion, and left serratus anterior block was given for analgesia. After thorough suctioning, the child was gently extubated, shifted to paediatric intensive care unit for 12 h monitoring and discharged on the 4th postoperative day from the hospital uneventfully.Figure 1: Hysterosalpingography cathetersFigure 2: Hysterosalpingography catheter cuff in the bronchusFigure 3: Confirmation of lung isolationWe document the first report of an off-label use of the balloon HSG catheter as a substitute for bronchial blocker after getting parental consent to publish. Balloon HSG catheter was described by Sholkoff in a technical report published in the American Journal of Roentgenology;[3] since then, there have been many modifications to the HSG catheter. The available HSG catheter is a 30 cm long malleable double lumen catheter with a soft concentric balloon, which has a maximal inflation volume of 1.5 ml. Two sizes are available – 5F and 7F with an open end, soft round distal tip, which accepts a 0.035” guidewire which aids in positioning the catheter. It has stop cocks for both catheter lumens, one for balloon inflation and the other intended for saline/contrast infusion. The cuff is designed for low pressure and is safe at 1 ml inflation with adequate seal. The size of the HSG catheter was selected according to the outer diameter and the age of the child [Figure 4].[4]Figure 4: Age-based selection of bronchial blockerHSG catheter was a perfect substitute for bronchial blockers in case of non-availability of paediatric bronchial blockers. Safety profile regarding the off-label usage can be justified by articles stating the least incidence of pain and mucosal damage to the fallopian tube (similar to the mucosa of the bronchial tree-ciliated epithelium). Patrone et al. demonstrated off-label use of HSG catheter in the removal of biliary stones.[5] The advantages included the option of bending the distal tip to steer it into the operative lung, the open-ended tip, which helped with passive lung deflation and suctioning on the operative side. The catheter did not require repositioning during surgery due to displacement due to its length, inherent stiffness of the catheter and use of saline for balloon inflation. Paediatric bronchial blockers cost begins at Rs. 3000 INR, which is more expensive than the ubiquitous and simple HSG catheter which costs at least Rs. 900 INR, thus making it a very attractive option for use in children in the age group of 2–8 years as a replacement for the bronchial blocker. Further studies are needed to confirm the safety of this device as a substitute for paediatric lung isolation as bronchial blockers. Limitations to use the HSG catheter for lung isolation, is the availability of rigid ventilating bronchoscope and ultrasonogram, to use it within safe limits. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.