Highlight
- Abdominal electrical stimulation combined with airway clearance significantly improves the strength of involuntary cough and abdominal muscle thickness in tracheostomized neurologic patients.
- The combination treatment notably increases the rate of successful decannulation compared to airway clearance alone.
- No significant impact on clinical pulmonary infection scores or resting diaphragm mobility was observed with abdominal electrical stimulation.
Study Background
Patients with neurological disorders who undergo tracheostomy often remain with an impaired ability to clear airway secretions effectively, placing them at higher risk of respiratory complications and prolonged dependence on tracheostomy tubes. Decannulation, or removal of the tracheostomy tube, is a critical milestone indicating improved airway protection and respiratory function. However, achieving successful decannulation remains challenging due to weakened respiratory muscles and ineffective cough mechanisms. Airway clearance techniques (ACTs) are standard in facilitating secretion mobilization, but adjunct therapies that enhance muscle strength and cough efficacy are needed to improve outcomes.
Abdominal electrical stimulation (AES) has emerged as a non-invasive modality aimed at enhancing muscle activation and strength. By electrically stimulating abdominal muscles, which contribute significantly to forced expiratory efforts during coughing, AES may improve cough efficiency and contribute to respiratory rehabilitation. This randomized controlled trial investigated whether combining AES with standard ACTs can improve decannulation success rates and related clinical measures in tracheostomized neurologic patients.
Study Design
This assessor-blinded randomized controlled trial enrolled 68 adult patients with neurologic disorders who had successfully been weaned off mechanical ventilation but remained tracheostomized. Participants were randomly allocated into two equal groups: one received conventional treatment with airway clearance techniques alone (control group), while the other received the same plus abdominal electrical stimulation therapy (experimental group). Treatment lasted 6 weeks for both groups.
Primary endpoint was the rate of successful decannulation at 6 weeks. Secondary endpoints included peak flow rate during involuntary coughing (an indicator of cough strength), clinical pulmonary infection score (to evaluate respiratory infection severity), abdominal muscle thickness, and resting diaphragmatic mobility assessed via ultrasonography.
Key Findings
At study completion, the experimental (AES + ACT) group demonstrated significant improvements compared with controls:
– Decannulation success rate: 93.3% in the experimental group vs. 73.3% in controls (Odds Ratio 5.07; 95% CI, 1.41–18.24; p = 0.013), indicating a robust clinical benefit.
– Peak involuntary cough flow rate: Significantly higher in the experimental group with a mean difference of 39.433 L/min (95% CI, 28.83–50.04; p < 0.001), highlighting enhanced cough efficacy.
– Abdominal muscle thickness: The experimental group showed an increase of 0.106 cm (95% CI, 0.08–0.13; p < 0.001), reflecting muscle hypertrophy or improved muscular tone.
– Clinical pulmonary infection scores: No significant difference was noted (p > 0.05), suggesting that AES does not independently alter infection burden.
– Resting diaphragmatic mobility: Similar across groups (p > 0.05), implying that AES effects may be localized to abdominal muscles without influencing diaphragm resting activity.
The safety profile of AES was not explicitly discussed, but no adverse events were reported, suggesting the intervention was well-tolerated.
Expert Commentary
The findings provide compelling evidence that adding abdominal electrical stimulation to standard airway clearance techniques can enhance respiratory muscle function and increase decannulation success in patients with neurological deficits. The improvement in involuntary cough flows is particularly important as effective cough is critical for airway protection and secretion clearance. Increased abdominal muscle thickness supports a physiological basis for enhanced expiratory effort.
Clinically, this may translate into shorter tracheostomy dependency and reduced complications associated with tracheostomy tubes. The lack of effect on diaphragmatic mobility and infection scores indicates that the benefits are likely mediated via enhanced abdominal musculature rather than global respiratory muscle changes or anti-infective effects.
Limitations include a relatively small sample size and a single-center setting, which may affect generalizability. Longer follow-up is also warranted to assess sustained benefits and safety. Future studies could explore optimization of stimulation parameters, integration with diaphragmatic pacing, and effects in other populations, such as patients with chronic respiratory failure.
Conclusion
The randomized, controlled trial demonstrates that abdominal electrical stimulation, when added to airway clearance techniques, significantly improves cough strength, abdominal muscle thickness, and decannulation success in tracheostomized patients with neurologic disorders. These findings support the incorporation of AES as a promising adjunct in respiratory rehabilitation for this vulnerable patient group. However, no differential effects were observed on pulmonary infection control or diaphragm resting mobility. Further multicenter studies are recommended to confirm these results and define best practice protocols.
Funding and Trial Registration
The original study details regarding funding sources and clinical trial registration were not provided in the available abstract.
References
1. Huo F, Xu H, Shao S, et al. Effects of Abdominal Electrical Stimulation Combined With Airway Clearance Techniques in Tracheotomized Patients With Neurological Disorders: A Randomized, Controlled Trial. Crit Care Med. 2026 Jul 17. PMID: 42467907.
2. Bach JR. Management of the respiratory complications of neuromuscular disease. Respir Care. 2005;50(10):1346-54.
3. McCaughey EJ, Harwood R, Ranger T, et al. Electrical stimulation of abdominal muscles to augment cough efficacy in tetraplegic patients: a systematic review. Spinal Cord. 2017;55(6):536-547.
4. Rabinovich RA, Vilaró J, Padilla G, et al. Outcome predictors for weaning from long-term mechanical ventilation in tracheostomized patients: a cohort study. BMJ Open. 2019;9(1):e022186.
