Anesthetic Management for Tracheoplasty in a Patient with Primary Tracheal Tumor

Technical Summary: Anesthetic Management for Tracheoplasty in a Patient with Primary Tracheal Tumor

Problem Statement
Primary tracheal tumors are rare respiratory neoplasms (incidence ~1 per million) that often present with severe tracheal stenosis. Surgical resection combined with tracheoplasty is the standard curative treatment; however, perioperative airway management poses a critical challenge. Conventional endotracheal intubation is frequently unfeasible in cases of severe stenosis (e.g., lumen diameter <3 mm), and the administration of muscle relaxants required for routine general anesthesia can precipitate complete airway obstruction. While Spontaneous Breathing Anesthesia (SBA) offers advantages by preserving native respiratory function, standardized regimens for tracheal tumor resection—particularly those involving complex nerve blocks to manage surgical reflexes—are lacking.

Methodology
This case report details the anesthetic management of a 58-year-old female with a malignant tracheal adenoid cystic carcinoma causing severe eccentric stenosis (minimum lumen diameter: 3 mm). The team employed a multimodal strategy centered on maintaining spontaneous breathing throughout the procedure:

1. Preoperative Preparation: Emergency tracheotomy kits and high-frequency ventilators were prepared as rescue measures. The patient provided informed consent for emergency tracheotomy under local anesthesia as a backup.
2. Sedation and Analgesia: The protocol utilized a combination of:
   • Ciprofol: 25 mg IV for initial sedation (chosen for low injection pain and short half-life).
   • Sufentanil: 10 µg IV for analgesia.
   • Dexmedetomidine: Continuous infusion at 0.4 µg/kg/h for sustained sedation with minimal respiratory depression.
3. Airway Management: A Laryngeal Mask Airway (LMA) was placed after the patient lost consciousness but before nerve blocks to facilitate ventilation. Crucially, no muscle relaxants were used.
4. Ultrasound-Guided Nerve Blocks: To inhibit surgical traction and vagal reflexes while preserving spontaneous breathing, the following blocks were performed:
   • Bilateral superficial cervical plexus block (10 mL 0.375% ropivacaine per side).
   • Bilateral cervical vagus nerve block (3 mL 0.375% ropivacaine per side).
   • Left deep cervical plexus block (10 mL 0.375% ropivacaine) to avoid bilateral phrenic nerve blockade and subsequent dyspnea.
5. Surgical Phase:
   • The patient was awakened, and the LMA was removed.
   • The diseased tracheal segment (3.5 cm) was resected under spontaneous breathing.
   • Oxygen was insufflated directly into the proximal tracheal stump via a suction catheter to maintain oxygenation during the transection.
   • The patient was instructed to actively flex the neck during end-to-end anastomosis to reduce tension.
   • Fixing sutures were placed from the mandible to the supraclavicular skin to prevent postoperative hyperextension.

Key Results

• Operative Success: The surgery was completed successfully with a total operative time of 210 minutes and anesthesia duration of 240 minutes.
• Physiological Stability: The patient maintained unobstructed spontaneous breathing throughout. Vital signs remained generally stable (HR 61–120 bpm, BP 121–161/62–100 mmHg, SpO₂ 93–100%).
• Hemodynamics: A transient increase in heart rate and blood pressure occurred immediately following the bilateral vagus nerve block due to surgical stimulation and relative sympathetic excitation; this was managed with intermittent low-dose sufentanil.
• Outcome: The patient regained full consciousness postoperatively, was transferred to the ward in a voluntary neck-flexed position, and recovered fully without severe airway complications or hemodynamic instability.

Key Contributions

• Feasibility of Bilateral Vagus Nerve Block: The report demonstrates the safety and efficacy of using ultrasound-guided bilateral vagus nerve blocks combined with sedation to suppress tracheal exploration reflexes and coughing during tracheal resection, a technique with limited prior clinical documentation.
• Hybrid Airway Strategy: It validates a specific protocol for critical airway stenosis: combining nerve blocks with low-dose sedation to preserve spontaneous breathing, utilizing an LMA for initial ventilation, and transitioning to direct oxygen insufflation during the critical resection phase.
• Risk Mitigation: The study highlights the importance of avoiding bilateral deep cervical plexus blocks to prevent phrenic nerve paralysis and the necessity of having a comprehensive emergency backup plan (including local tracheotomy) when attempting such high-risk anesthetic techniques.

Significance and Claims
The authors claim that this case verifies the safety and feasibility of a combined strategy involving multimodal nerve blocks, sedation/analgesia, and the preservation of spontaneous breathing for tracheoplasty in patients with severe tracheal stenosis. They posit that for patients where conventional intubation is unfeasible, individualized anesthetic protocols that prioritize spontaneous breathing and include comprehensive emergency backup plans can effectively ensure perioperative safety. The paper concludes that while this approach is a reliable alternative, it requires careful patient selection, thorough risk assessment, and advanced airway management skills, noting that preoperative preparation for extracorporeal circulation was not deemed necessary for this specific case but may be considered for future extremely high-risk patients.