Microlaryngeal surgery (MLS) encompasses a range of delicate diagnostic and operative procedures on the larynx, including excision of polyps, nodules, cysts, Reinke's oedema, and early-stage malignancies. ¹ The nature of this surgery demands an immobile surgical field, a bloodless operative site, and clear visualisation of the vocal cords, making the anaesthetic technique pivotal to its success. ² The fundamental challenge for the anaesthesiologist lies in managing the patient's airway and gas exchange while simultaneously surrendering the larynx to the surgeon, creating a true "shared airway" scenario. ³

The historical approach to MLS involved intermittent apnoea, where the patient is hyperventilated with 100% oxygen, the tube is removed to allow the surgeon brief periods of work, and then ventilation is reinstated. However, this technique is inefficient, poses risks of hypoxaemia and hypercapnia, and is unsuitable for prolonged procedures. ⁴ The modern approaches primarily involve either endotracheal intubation with a small-diameter tube (e.g., 5.0-6.0 mm ID) or various forms of jet ventilation (supraglottic, subglottic, or transtracheal). ^5,6 Each technique has its advantages and drawbacks concerning surgical access, control of ventilation, and risk of barotrauma.

The choice of anaesthetic agents is equally critical. Inhalational anaesthetics can cause airway irritation and are difficult to administer during jet ventilation due to atmospheric pollution and lack of precision. ⁷ Total intravenous anaesthesia (TIVA) with propofol and a short-acting opioid like remifentanil has gained widespread favour. ⁸ Propofol provides smooth induction, rapid emergence, and antiemetic properties, while remifentanil, with its context-sensitive half-time of 3-5 minutes regardless of infusion duration, offers profound analgesia and suppression of airway reflexes without prolonging recovery. ^9,10

This combination facilitates a profound level of anaesthesia that blunts haemodynamic responses to laryngoscopy and surgical stimulation, provides excellent conditions for the surgeon, and allows for a swift return of laryngeal reflexes and consciousness postoperatively, thereby enhancing patient safety. ¹¹ Despite its theoretical benefits, prospective data on the comprehensive outcomes of this technique, including haemodynamic stability, surgical condition scores, and detailed recovery metrics in a contemporary clinical setting, are valuable. This prospective observational study aims to evaluate the efficacy and safety of a TIVA-based anaesthetic regimen for patients undergoing elective MLS.

This prospective observational study was conducted after obtaining approval from the institutional ethics committee and written informed consent from all participants. The study enrolled 75 American Society of Anesthesiologists (ASA) physical status I-III patients aged between 18 and 65 years, scheduled for elective MLS over a period of six months.

Inclusion Criteria:

1. Patients aged 18-65 years.
2. ASA physical status I, II, or III.
3. Scheduled for elective microlaryngeal procedure (e.g., vocal cord polyp excision, microlaryngoscopy, biopsy).
4. Patients providing written informed consent.

Exclusion Criteria:

1. Patient refusal.

2.Known allergy or contraindication to propofol, remifentanil, or neuromuscular blocking agents.

3.Significant cardiovascular, respiratory (especially severe COPD or asthma), hepatic, or renal disease.

4. Pregnancy or lactation.
5. Morbid obesity (Body Mass Index > 35 kg/m²).
6. Predicted difficult airway.
7. Significant gastroesophageal reflux disease.

All patients underwent standard pre-anaesthetic assessment. After securing intravenous access and standard monitoring (ECG, NIBP, SpO₂), premedication with intravenous midazolam (0.02 mg/kg) was administered. Anaesthesia was induced with fentanyl (1-2 mcg/kg), propofol (2-2.5 mg/kg), and rocuronium (0.6 mg/kg) to facilitate tracheal intubation. A small-bore microlaryngeal tube (size 5.0-6.0 mm ID) was used for intubation in all cases. Anaesthesia was maintained with a continuous infusion of propofol (75-150 mcg/kg/min) and remifentanil (0.05-0.25 mcg/kg/min), titrated to maintain haemodynamic stability within ±20% of baseline values. Neuromuscular blockade was maintained with intermittent boluses of rocuronium. Ventilation was controlled to maintain normocapnia (EtCO₂ 35-45 mmHg). At the end of surgery, anaesthetic infusions were stopped, and neuromuscular blockade was antagonized with neostigmine and glycopyrrolate. The time from cessation of infusions to eye-opening on command and to achieving an Aldrete score of ≥9 was recorded. Haemodynamic variables (Heart Rate, Systolic and Diastolic Blood Pressure) were recorded at baseline, after induction, during laryngoscopy, at 5-minute intervals intraoperatively, and at extubation. The operating surgeon, blinded to the anaesthetic drug titration, assessed the quality of the surgical field every 15 minutes using a 5-point Surgical Condition Score (SCS: 1=extremely poor, 2=poor, 3=acceptable, 4=good, 5=excellent). Any complications, such as desaturation, coughing, laryngospasm, or postoperative nausea and vomiting (PONV), were noted.

Table 1: Patient Demographics and Surgical Data (n = 75)

VOC: Vocal Cord Surgery (Polyps, Nodules)

Table 2: Haemodynamic Parameters (Mean ± SD)

* Statistically significant compared to baseline (p<0.05)

Table 3: Distribution of Surgical Condition Scores (SCS)

Total assessments: 335 (across 75 patients)

Table 4: Recovery Profile (Mean ± SD)

Table 5: Postoperative Complications (n = 75)

Table 6: Anaesthetic Agent Consumption (Mean ± SD)

Atopic dermatitis (AD) is one of the most common chronic skin disorders in childhood, affecting between 5% and 20% of children worldwide [18,19]. In Singapore, a large study of 12,323 schoolchildren aged 7 to 16 years reported a prevalence of 21% in a predominantly Asian population [20]. Similarly, a cross-sectional study from Northern Europe demonstrated a prevalence of 15.6% among children using an investigator-developed questionnaire, which was validated against Hanifin and Rajka’s criteria [21]. Laughter et al reported a prevalence of 17% in Oregon schoolchildren, although the use of stricter diagnostic thresholds yielded a more conservative estimate of 7% [19]. These variations highlight the methodological challenges in determining the true prevalence of AD through population-based questionnaires. Although AD may persist into adulthood, childhood disease remains far more common, and approximately 60% of patients achieve remission by adulthood [22].

In the present study, the most frequently affected quality of life components, as assessed by the Children’s Dermatology Life Quality Index (CDLQI), were itching (83.8%), sleep disturbance (66.2%), and limitations in play activities (62.3%). These findings reinforce the significant impact of AD on daily life, with pruritus and sleep disruption emerging as the most burdensome symptoms. Ben-Gashir et al similarly observed that itching contributed the highest proportion of CDLQI scores, with nearly three-quarters of children experiencing itchy, painful, or uncomfortable skin [23]. This pattern is consistent with the original validation of the CDLQI, where symptoms and feelings were the domains most strongly affected [11,23].

The CDLQI has proven to be a valuable tool in assessing the psychosocial burden of dermatologic conditions in children. Studies have shown that not only AD, but also other chronic skin disorders such as vitiligo, negatively influence quality of life, with improvements in disease activity correlating with reductions in CDLQI scores [24]. More recent work has confirmed that AD significantly impairs the quality of life of both children and toddlers, particularly in the domains of itch, self-consciousness, dressing, sleep, and treatment-related difficulties [25–27]. In these studies, at least 60% of children reported being affected to some degree by their skin disease, and up to 85% of toddlers experienced substantial disruption across multiple domains [25]. Ben-Gashir et al [23] also demonstrated that quality of life impairment correlated closely with AD severity, further supporting the utility of the CDLQI in community-based research.

In our cohort, most children presented with moderate disease (44.6%), followed by mild (35.4%) and severe (20.0%), with a mean SCORAD score of 8.4 ± 3.6. Pruritus was reported in the majority of cases (95.4%), while sleep disturbance affected over half (52.3%). Similar to our findings, Emerson et al [27] and Lewis-Jones et al [28] reported low quality of life scores in children with eczema, though differences in study design and outcome measures limit direct comparison. Nonetheless, these results consistently demonstrate that AD exerts a substantial burden on children and their families, even in the absence of active eczema lesions [23].

The psychosocial implications of AD extend beyond symptoms. Children with atopic dermatitis often experience behavioral difficulties, including increased dependency, fearfulness, and disturbed sleep [29]. Such problems may interfere with social and intellectual development, with peer and teacher interactions sometimes compromised by concerns about appearance, fear of contagion, or restrictions in physical activities [30]. Sleep disruption, largely due to nocturnal itching and scratching, is particularly significant. Yosipovitch et al [31] reported that 84% of AD patients had difficulty falling asleep and 79% experienced nocturnal awakenings due to pruritus. Objective sleep studies using actigraphy confirm these findings, showing increased nighttime activity and poorer sleep quality in children with AD compared to controls [32]. Reid et al further estimated that affected children may lose up to 2 hours of sleep per night. Such chronic sleep loss contributes to daytime somnolence, impaired school performance, and mood disturbances, while the use of sedating antihistamines can compound these effects [33].

Overall, our findings highlight the substantial morbidity associated with childhood AD. The interplay of pruritus, sleep disturbance, and psychosocial impairment underscores the need for comprehensive management strategies that address not only disease severity but also the broader quality of life of affected children and their families.

This study demonstrates that total intravenous anaesthesia utilizing propofol and remifentanil is a highly effective and safe technique for microlaryngeal surgery. It provides outstanding haemodynamic stability, creates superior surgical conditions characterised by an immobile and bloodless field, and ensures a rapid, smooth, and predictable recovery with a low incidence of postoperative complications. This regimen successfully addresses the unique challenges of the shared airway in MLS and should be considered a gold-standard anaesthetic approach for these procedures.

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