Characteristics of 24-hour ambulatory blood pressure monitoring in a COVID-19 survivor.

COVID-19 infection primarily causes severe pneumonia complicated by acute respiratory distress syndrome and multiorgan failure requiring a ventilator support. We present a case of a 55-year-old male, admitted with COVID-19. He was obese but had no other medical conditions. His blood pressure was measured by his general physician on several occasions in the past, all values being normal (<140/90 mmHg). He developed multiorgan failure, requiring vasopressor and ventilator support for 17 days. A prone positioning improved the arterial oxygenation, and reduced the need for supplemental oxygen. After recovery, he showed persistently elevated blood pressure and sinus tachycardia both in clinic and out-of-clinic. The activation of the renin-angiotensin-aldosterone and sympathetic systems, volume-overload, hyperreninemia and cytokine storm might have contributed to the exaggerated cardiovascular response.

Diffusion capacity and CT measures of emphysema and airway wall thickness - relation to arterial oxygen tension in COPD patients.

BACKGROUND: Decreased diffusing capacity of the lung for carbon monoxide (DLCO) is associated with emphysema. DLCO is also related to decreased arterial oxygen tension (PaO2), but there are limited data on associations between PaO2 and computed tomography (CT) derived measures of emphysema and airway wall thickness. OBJECTIVE: To examine whether CT measures of emphysema and airway wall thickness are associated with level of arterial oxygen tension beyond that provided by measurements of diffusion capacity and spirometry. METHODS: The study sample consisted of 271 smoking or ex-smoking COPD patients from the Bergen COPD Cohort Study examined in 2007-2008. Emphysema was assessed as percent of low-attenuation areas<-950 Hounsfield units (%LAA), and airway wall thickness as standardised measure at an internal perimeter of 10 mm (AWT-Pi10). Multiple linear regression models were fitted with PaO2 as the outcome variable, and %LAA, AWT-Pi10, DLCO and carbon monoxide transfer coefficient (KCO) as main explanatory variables. The models were adjusted for sex, age, smoking status, and haemoglobin concentration, as well as forced expiratory volume in one second (FEV1). RESULTS: Sixty two per cent of the subjects were men, mean (SD) age was 64 (7) years, mean (SD) FEV1 in percent predicted was 50 (15)%, and mean PaO2 (SD) was 9.3 (1.1) kPa. The adjusted regression coefficient (CI) for PaO2 was -0.32 (-0.04-(-0.019)) per 10% increase in %LAA (p<0.01). When diffusion capacity and FEV1 were added to the model, respectively, the association lost its statistical significance. No relationship between airway wall thickness and PaO2 was found. CONCLUSION: CT assessment of airway wall thickness is not associated with arterial oxygen tension in COPD patients. Emphysema score measured by chest CT, is related to decreased PaO2, but cannot replace measurements of diffusion capacity in the clinical evaluation of hypoxaemia.

Oxygen desaturation in 6-min walk test is a risk factor for adverse outcomes in COPD.

The 6-min walk test (6MWT) is an exercise test that measures functional status in chronic obstructive pulmonary disease (COPD) patients and provides information on oxygen desaturation. We investigated oxygen desaturation during 6MWT as a risk factor for important COPD outcomes: mortality, frequency of exacerbations, decline in lung function and decline in lean body mass.433 COPD patients were included in the Bergen COPD Cohort Study 2006-2009, and followed-up for 3 years. Patients were characterised using spirometry, bioelectrical impedance measurements, Charlson comorbidity score, exacerbation history, smoking and arterial blood gases. 370 patients completed the 6MWT at the baseline of the study. Information on all-cause mortality was collected in 2011.Patients who experienced oxygen desaturation during the 6MWT had an approximately twofold increased risk of death (hazard ratio 2.4, 95% CI 1.2-5.1), a 50% increased risk for experiencing later COPD exacerbations (incidence rate ratio 1.6, 95% CI 1.1-2.2), double the yearly rate of decline in both forced vital capacity and forced expiratory volume in 1 s (3.2% and 1.7% versus 1.7% and 0.9%, respectively) and manifold increased yearly rate of loss of lean body mass (0.18 kg·m(-2) versus 0.03 kg·m(-2) among those who did not desaturate).Desaturating COPD patients had a significantly worse prognosis than non-desaturating COPD patients, for multiple important disease outcomes.