INFLUENCE OF HIGH FREQUENCY CHEST WALL OSCILLATION IN HOSPITALIZED PATIENTS WITH COVID-19

Arterial blood gas analysis is a common investigation in emergency departments and intensive care units for monitoring patients with acute respiratory failure. ABG also has some applications in general practice, such as assessing the need for domiciliary oxygen therapy in patients with chronic obstructive pulmonary disease. An arterial blood gas result can help in the assessment of a patient's gas exchange, ventilator control and acid-base balance. (Verma et al., 2010)

The neutrophil-to-lymphocyte ratio (NLR) is an inflammatory marker derived from combining the absolute blood neutrophil and lymphocyte counts, two routinely performed parameters in clinical settings. Recently, studies have reported that NLR levels were higher in more severe patients and were suggested to confer a prognostic value in COVID-19 patients (Lagunas et al.,2020).

Earlier diagnosis of COVID-19 may be facilitated by heart rate (HR) and heart rate variability (HRV) monitoring. HR and HRV parameters could not only help to detect COVID-19 in a timely manner but could also help to identify patients at risk for cardiovascular/pulmonary complications. Additionally, HRV and HR parameters may help to assess the course of the disease. (Buchhorn et al., 2020).

The World Health Organization indicates that a resting value of RR > 30 breaths/min is a critical sign for the diagnosis of severe pneumonia in adults, while the cut-off value for children varies according to age (World Health Organization, 2020).

Resting RR values also contribute to the prognosis of COVID-19 patients as ICU admission and mortality are associated with significantly higher RR values compared to non-ICU patients and survivors (Huang et al., 2020 & Zhou et al., 2020).

Levels of dyspnea appear to vary significantly amongst patients suffering from COVID-19 ranging from 18.6 to 59%. (Guan et al., 2020). More recently, Li et al (2020) systematic review on 1,994 COVID-19 patients showed an overall percentage of patients experiencing dyspnea was 21.9% in addition. Huang et al. found a prevalence of breathlessness as high as 92% amongst COVID- 19 patients hospitalized in intensive care units versus 37% in non-intensive care units. (Huang et al.,2020).

C-reactive protein) CRP) was an independent risk factor for severe COVID-19. The optimal working point was 38.55 mg/L. This is consistent with previous research showing that hypoalbuminemia, lymphopenia, and CRP more than equal to 40 mg/L were the predictive factors for pneumonia progression to respiratory failure (Ko et al., 2016). Besides, higher CRP has been linked to unfavorable aspects of COVID-19 diseases, such as cardiac injury, and ARDS development, and death. (Terpos et al., 2020).

The Dyspnea-12 (D-12) Questionnaire is a convenient patient-reported scale for measuring the severity of breathlessness. Breathlessness is quantified by using 12 descriptors to cover both the physical and the psychological dimensions. The D-12 has established its validity and reliability in COPD, asthma, interstitial lung disease, and pulmonary hypertension. (Yorke et al., 2010).

Severe COVID-19 patients were more likely to present with higher levels of inflammation upon hospital admission.