Double trouble - Airway equipment problem in a difficult airway!

Abstract

Sir, A 11-year-old boy weighing 29 kg was posted for pelvic supporting osteotomy with limb lengthening and external fixation. He had a history of sepsis in infancy with post-sepsis sequelae and resultant limb length discrepancy. The patient also had surgery six years ago for posttraumatic bilateral temporomandibular ankylosis. Bilateral distraction osteotomy followed by release of ankylosis was performed in a two-stage procedure. On examination, he had micrognathia and retrognathia, with a mouth opening restricted to 2 cm [Figure 1]. He was otherwise healthy, and blood investigations were within normal limits.Figure 1: (a) Patient profile showing significant retrognathia (b) Limited mouth openingWe anticipated a difficult airway and planned to conduct the case under general anaesthesia using supraglottic airway device (SAD), with femoral nerve block for analgesia. Plan B, in case SAD insertion failed, was fibreoptic-guided tracheal intubation. The operating room preparation included difficult airway cart and team briefing about the airway plan. An intravenous line was secured prior to induction. The child was very anxious, so 1 mg midazolam was administered under monitoring. Following administration of glycopyrrolate 4 μg/kg and fentanyl 2 μg/kg, inhalational induction with incremental sevoflurane in 100% oxygen was performed. Once ability to mask ventilate was confirmed, we administered propofol 3 μg/kg. Laryngeal mask airway (LMA) Supreme® size 2.5 was chosen (over our standard preference of i-gel® airway) since it has a rather lean profile which we thought would easily fit into the narrow oral cavity. LMA insertion was easy, and adequate ventilation was achieved with a good seal. Muscle relaxant was avoided and patient was ventilated on pressure support mode with oxygen, air and sevoflurane using low flow anaesthesia. Midway through the procedure, the attending anaesthetist (our fellow in paediatric anaesthesia) noticed that the ventilator bellows had suddenly collapsed and the end-tidal carbon dioxide (EtCO2)value fell from 35 mmHg to 20 mmHg. He immediately took the reservoir bag in hand and started manual ventilation with 100% oxygen. The consultant anaesthetist was called for help and manual ventilation revealed a large leak in the LMA. Functional airway obstruction (laryngospasm, bronchospasm), shifting of the LMA were some of the differentials that came to mind. 1 mg/kg of propofol was administered and decision to change the LMA was taken. The orthopaedic surgeons were informed about the problem and requested to stop surgery. When the tapes securing the LMA were removed and the LMA Supreme® was taken out, we noticed a breach at proximal end at the junction of the bite block, causing the massive leak and loss of ventilation [Figure 2]. Another LMA Supreme® was inserted and the rest of the case proceeded uneventfully. Prompt detection, identification of the problem and timely intervention prevented fall in oxygen saturation. We are a close-knit team of paediatric anaesthetists, fellows and experienced technicians, and the shared understanding of the case ensured efficient crisis management.Figure 2: LMA Supreme® with arrow indicating site of breakage at the junction of shaft with the bite portionWe did a root cause analysis and also conducted a team debriefing after the case. The LMA Supreme® used was a near expiry device, and we believe it may have deteriorated during storage leading to the breakage. On performing a literature search, we found a report of breakage of LMA Supreme® similar to our case.[1] We decided to send this communication for publication to highlight the following points. A visual inspection to confirm the integrity of the airway device and the cuff (in case of cuffed SADs) should be part of the mandatory anaesthesia trolley pre-check. Excessive reuse of reusable SADs can also result in damage.[2] Team briefing is vital prior to every case; especially so for difficult cases. Wherever possible, in DA cases, spontaneous ventilation, avoidance of muscle relaxant and “not to burn bridges” is a sensible, safe approach.[3] Age and weight appropriate “standby” equipment should be immediately available for rescue, such as in our case. Soft skills, for example, team work and communication play an important role in crisis management. Debriefing with the entire team is equally important after critical events to assess and improve team performance and to promote a culture of safety. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given his consent for images and other clinical information to be reported in the journal. The guardian understands that names 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.