Significant hypercapnia as an initial manifestation of COVID-19 without typical symptoms in chronic cervical spinal cord injury: A case series

CONTEXT: Few reports have described how Coronavirus Disease 2019 (COVID-19) presents in patients with long-standing high cervical spinal cord injury (SCI). This case series suggests that clinically significant hypercapnia may be an early manifestation of COVID-19 in this population, even without classic respiratory symptoms or marked oxygen desaturation, potentially delaying recognition of ventilatory failure. FINDINGS: We describe two men with chronic C4 ASIA Impairment Scale (AIS) A. Case 1: A 76-year-old vaccinated man developed drowsiness, confusion, and headache without cough or fever. Room-air oxygen saturation was 90-95%, and inflammatory markers did not clearly indicate infection. Arterial blood gas (ABG) showed new-onset, clinically significant hypercapnia (pH 7.306, PaCO₂ 62.4 mmHg, PaO₂ 77.3 mmHg). He required endotracheal intubation and intensive care unit (ICU) care; COVID-19 was subsequently confirmed and remdesivir was administered. Tracheostomy was later performed after unsuccessful ventilator weaning. Case 2: A 70-year-old unvaccinated man reported chest discomfort without cough or fever, then developed confusion. Room-air oxygen saturation remained 94-95%. ABG showed respiratory acidosis with new-onset, clinically significant hypercapnia (pH 7.304, PaCO₂ 59.4 mmHg, PaO₂ 76.7 mmHg). He also required intubation, mechanical ventilation, ICU care, and tracheostomy after COVID-19 was confirmed; he was treated with remdesivir and corticosteroids. CONCLUSION/CLINICAL RELEVANCE: These cases suggest that hypercapnia may be an early and potentially critical manifestation of COVID-19 in chronic high cervical SCI, without typical respiratory symptoms or marked hypoxemia. Clinicians should assess CO₂ retention in this vulnerable population to avoid delayed diagnosis and deterioration.