Effective treatment with oral Salbutamol on late onset respiratory impairment in a DOK7 Congenital Myasthenia Syndrome: a case report.

INTRODUCTION: DOK7 gene deficiency is a neuromuscular disease with an alteration in post-synaptic neuromuscular junction, leading to progressive respiratory impairment. Although, the therapy is not standardized, adrenergic agonists are suggested as first-line treatment.  Case presentation: Our patient had an ambiguous late childhood-onset and had a generalized muscle weakness free of respiratory symptoms during the early phase of the disease. Subsequently, when the respiratory muscle and the diaphragm involvement was impaired, a substantial loss of respiratory function with hypopneas and severe desaturation was detected. It was noteworthy the striking respiratory beneficial impact of oral salbutamol in the resolution of symptoms and functional impairments, leading to a remarkable respiratory improvement and a better quality of life.  Conclusion: Oral salbutamol treatment combined to a timely clinical recognition led to an outstanding respiratory improvement.

Standardizing PaO2 for PaCO2 in P/F ratio predicts in-hospital mortality in acute respiratory failure due to Covid-19: A pilot prospective study.

INTRODUCTION: Up to fifteen percent of patients with novel pandemic coronavirus disease (Covid-19) have acute respiratory failure (ARF). Ratio between arterial partial pressure of oxygen (PaO2) and fraction of inspired oxygen (FiO2), P/F, is currently used as a marker of ARF severity in Covid-19. P/F does not reflect the respiratory efforts made by patients to maintain arterial blood oxygenation, such as tachypnea and hyperpnea, leading to hypocapnia. Standard PaO2, the value of PaO2 adjusted for arterial partial pressure of carbon dioxide (PaCO2) of the subject, better reflects the pathophysiology of hypoxemic ARF. We hypothesized that the ratio between standard PaO2 over FiO2 (STP/F) better predicts Covid-19 ARF severity compared to P/F. METHODS: Aim of this pilot prospectic observational study was to observe differences between STP/F and P/F in predicting outcome failure, defined as need of invasive mechanical ventilation and/or deaths in Covid-19 ARF. Accuracy was calculated using Receiver Operating Characteristics (ROC) analysis and areas under the ROC curve (AUROC) were compared. RESULTS: 349 consecutive subjects admitted to our respiratory wards due to Covid-19 ARF were enrolled. STP/F was accurate to predict mortality and superior to P/F with, respectively, AUROC 0.710 versus 0.688, p = 0.012.Both STP/F and PF were accurate to predict outcome failure (AUROC respectively of 0.747 and 0.742, p = 0.590). DISCUSSION: This is the first study assessing the role of STP/F in describing severity of ARF in Covid-19. According to results, STP/F is accurate and superior to P/F in predicting in-hospital mortality.