Pulmonary Hemodynamics in Chronic Obstructive Pulmonary Disease of the Emphysematous Type

Abstract

Pulmonary hemodynamics have been extensively investigated in patients with chronic bronchitis or in ‘mixed’ patients (chronic bronchitis + emphysema) but rarely in patients with markedly predominant emphysema. We have investigated a large series (n = 151) of such patients, emphysema having been assessed on radiological, clinical and functional grounds. The mean age was 58 ± 10 years; vital capacity (VC, % of predicted) = 81 ± 19; forced expiratory volume in 1 s (FEV1)= 1,198 ± 589 ml; FEV₁/VC = 38 ± 12%; PaO₂ = 72 ± 11 mm Hg; PaCO₂ = 37,5 mm Hg. Pulmonary hypertension (PH), defined by a resting pulmonary artery pressure (PAP) of ≥20 mm Hg, was present in only 31 of 151 patients. During steady-state exercise (40 W or less) an abnormally high PAP (≥30 mm Hg) was observed in 99 of 151 patients. Resting and exercising PAP were poorly correlated with resting PaO₂ and PaCO₂, but were better correlated with the amplitude of the respiratory pressure swings, FEV₁, the transfer factor and exercising PaO₂. Patients with PH (n = 31) showed significantly more obstruction and pulmonary distension than the remainder, but they did not differ from the non-PH patients with regard to resting PaO₂. It is concluded that: (1) resting PH is not the rule in diffuse emphysema but exercising hypertension is frequent (2 of 3 patients), and (2) hypoxemia is not a determining factor of hemodynamic abnormalities in emphysema

Update on pulmonary hypertension complicating chronic obstructive pulmonary disease

“…21% of subjects had PH at rest and 66% with exercise. 10 PAP exhibited an inverse relationship with FEV 1 and no relation to resting arterial oxygen saturation. Scharf and colleagues evaluated 120 patients recruited in the National Emphysema treatment trial (NETT).…”

“…11 Patients included in this study had more severe airway obstruction (FEV 1 27%) compared to prior study. 10 Regression analysis showed diffusion capacity and FEV 1 correlated with mean PAP. No relation between resting oxygen saturation and mean PAP was noted.…”

Pulmoner hipertansiyonlu KOAH’lı olgularda pulmoner rehabilitasyon etkinliği

“…Bu artış, akım artışı, hipoksi ve intratorasik basınç dalgalanmasına bağlı olarak meydana gelebilmektedir (20). İstirahat halinde pulmoner hemodinamik parametreleri normal olan 2/3 KOAH tanılılarda bile bu durum görülebilmektedir (21,22).…”

Prevalence of Pulmonary Hypertension in Patients with Chronic Obstructive Pulmonary Disease: A Prospective Clinical Study.

“…Son olarak PH patofizyolojisinde diğer bir etkenin de infl amasyon ve amfizeme bağlı kapiller arter destruksiyonu olduğu belirtilmektedir 4 . KOAH'ı olan hastaların üçte ikisinde dinlenme halindeki PAB normal olmasına rağmen, egzersiz halinde orantısız biçimde PAB artışı olmaktadır 10,11 . Bu hastaların ileri dönemde dinlenme halinde PH gelişimi için risk altında olduğu düşünülmektedir 12 .…”