Decreasing size of cardiogenic oscillations reflects decreasing compliance of the respiratory system during long-term ventilation

2004 ◽  
Vol 96 (3) ◽  
pp. 879-884 ◽  
Author(s):  
Michael Lichtwarck-Aschoff ◽  
Bela Suki ◽  
Anders Hedlund ◽  
Ulf H. Sjöstrand ◽  
Agneta Markström ◽  
...  

Part of the energy produced by the heartbeat is transferred to the lung and promotes intrapulmonary gas mixing. It is likely that this transmission in the form of local mechanical disturbances affects and reflects respiratory mechanics. The effects of the cardiogenic oscillations were studied in seven piglets during 7 h of monotonous mechanical ventilation. During the 1st h of ventilation, every heartbeat triggered a noticeable transient increase in lung volume of 14 ml (95% confidence interval = 10-17 ml). After 7 h, the increase in lung volume due to heartbeat significantly decreased to 7 ml (95% confidence interval = 2-9 ml, P < 0.05). During the course of ventilation, overall lung compliance and gas exchange were progressively compromised. We conclude that 1) sufficient mechanical energy is transferred from the beating heart to the lung to increase lung volume, and 2) the ability of the heartbeats to help increase lung volume is reduced during long-term ventilation, which reflects the changes in lung compliance.

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Sara C. Auld ◽  
Hardy Kornfeld ◽  
Pholo Maenetje ◽  
Mandla Mlotshwa ◽  
William Chase ◽  
...  

Abstract Background While tuberculosis is considered a risk factor for chronic obstructive pulmonary disease, a restrictive pattern of pulmonary impairment may actually be more common among tuberculosis survivors. We aimed to determine the nature of pulmonary impairment before and after treatment among people with HIV and tuberculosis and identify risk factors for long-term impairment. Methods In this prospective cohort study conducted in South Africa, we enrolled adults newly diagnosed with HIV and tuberculosis who were initiating antiretroviral therapy and tuberculosis treatment. We measured lung function and symptoms at baseline, 6, and 12 months. We compared participants with and without pulmonary impairment and constructed logistic regression models to identify characteristics associated with pulmonary impairment. Results Among 134 participants with a median CD4 count of 110 cells/μl, 112 (83%) completed baseline spirometry at which time 32 (29%) had restriction, 13 (12%) had obstruction, and 9 (7%) had a mixed pattern. Lung function was dynamic over time and 30 (33%) participants had impaired lung function at 12 months. Baseline restriction was associated with greater symptoms and with long-term pulmonary impairment (adjusted odds ratio 5.44, 95% confidence interval 1.16–25.45), while baseline obstruction was not (adjusted odds ratio 1.95, 95% confidence interval 0.28–13.78). Conclusions In this cohort of people with HIV and tuberculosis, restriction was the most common, symptomatic, and persistent pattern of pulmonary impairment. These data can help to raise awareness among clinicians about the heterogeneity of post-tuberculosis pulmonary impairment, and highlight the need for further research into mediators of lung injury in this vulnerable population.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2607
Author(s):  
Yuzhen Gao ◽  
Jingjing Cao ◽  
Pan Xing ◽  
Ralf Altmeyer ◽  
Youming Zhang

Respiratory syncytial virus (RSV) is a major pathogen that causes severe lower respiratory tract infection in infants, the elderly and the immunocompromised worldwide. At present no approved specific drugs or vaccines are available to treat this pathogen. Recently, several promising candidates targeting RSV entry and multiplication steps are under investigation. However, it is possible to lead to drug resistance under the long-term treatment. Therapeutic combinations constitute an alternative to prevent resistance and reduce antiviral doses. Therefore, we tested in vitro two-drug combinations of fusion inhibitors (GS5806, Ziresovir and BMS433771) and RNA-dependent RNA polymerase complex (RdRp) inhibitors (ALS8176, RSV604, and Cyclopamine). The statistical program MacSynergy II was employed to determine synergism, additivity or antagonism between drugs. From the result, we found that combinations of ALS8176 and Ziresovir or GS5806 exhibit additive effects against RSV in vitro, with interaction volume of 50 µM2% and 31 µM2% at 95% confidence interval, respectively. On the other hand, all combinations between fusion inhibitors showed antagonistic effects against RSV in vitro, with volume of antagonism ranging from −50 µM2 % to −176 µM2 % at 95% confidence interval. Over all, our results suggest the potentially therapeutic combinations in combating RSV in vitro could be considered for further animal and clinical evaluations.


Author(s):  
Tsuyoshi Yamabe ◽  
Yanling Zhao ◽  
Paul A Kurlansky ◽  
Suzuka Nitta ◽  
Saveliy Kelebeyev ◽  
...  

Abstract OBJECTIVES Chronic kidney disease (CKD) is prevalent in patients undergoing cardiovascular surgery, and it negatively impacts procedural outcomes; however, its influence on the outcomes of aortic surgery has not been well studied. This study aims to elucidate the importance of CKD on the outcomes of aortic root replacement (ARR). METHODS Patients who underwent ARR between 2005 and 2019 were retrospectively reviewed (n = 882). Patients were divided into 3 groups based on the Kidney Disease: Improving Global Outcomes criteria: Group 1 [estimated glomerular filtration rate (eGFR) ≥ 60 ml/min/1.73 m2, n = 421); Group 2 (eGFR = 30–59 ml/min/1.73 m2, n = 424); and Group 3 (eGFR &lt; 30 ml/min/1.73 m2, n = 37). To reduce potential confounding, a propensity score matching was also performed between Group 1 and the combined group of Group 2 and Group 3. The primary end point was 10-year survival. Secondary end points were in-hospital mortality and perioperative morbidity. RESULTS Severe CKD patients presented with more advanced overall chronic and acute illnesses. Kaplan–Meier analysis showed a significant correlation between CKD stage and 10-year survival (log-rank P &lt; 0.001). The number of events for Group 1 was 15, Group 2 was 49 and Group 3 was 11 in 10 years. Group 3 had significantly higher in-hospital mortality (13.5% vs 3.5% in Group 2 vs 0.7% in Group 1, P &lt; 0.001) and stroke (8.1% vs 7.1% vs 1.2%, P &lt; 0.001) as well as introduction to new dialysis (27.0% vs 5.4% vs 1.7%, P &lt; 0.001). eGFR was shown to be an independent predictor of mortality (hazard ratio, 0.98; 95% confidence interval, 0.96–0.99). Comparison between propensity matched groups showed similar postoperative outcomes, and eGFR was still identified as a predictor of mortality (hazard ratio, 0.97; 95% confidence interval, 0.95–0.99). CONCLUSIONS Higher stage in CKD negatively impacts the long-term survival in patients who are undergoing ARR.


Author(s):  
Igor Belluschi ◽  
Elisabetta Lapenna ◽  
Davide Carino ◽  
Cinzia Trumello ◽  
Manuela Cireddu ◽  
...  

Abstract OBJECTIVES Previous series showed the outcomes of thoracoscopic ablation of stand-alone symptomatic paroxysmal atrial fibrillation (AF) for up to 7 years of follow-up. The goal of this study was to assess the long-term durability of surgical pulmonary vein isolation (PVI) beyond 7 years. METHODS Fifty consecutive patients {mean age 55 [standard deviation (SD): 11.2] years, previous catheter ablation in 56%, left ventricular ejection fraction 60% (SD: 4.6), left atrium volume 65 ml (SD: 17)} with stand-alone symptomatic paroxysmal AF underwent PVI through bilateral thoracoscopy ablation between 2005 and 2014. The CHA2DS2-VASc score was ≥2 in 12 patients (24%). RESULTS No hospital deaths occurred. At hospital discharge all patients but 1 (2%) were in sinus rhythm (SR). Follow-up was 100% complete [mean 8.4 years (SD: 2.3), max 15]. The 8-year cumulative incidence function of AF recurrence, with death as a competing risk, on or off class I/III antiarrhythmic drugs (AADs)/electrocardioversion/re-transcatheter ablation (TCA) was 20% (SD: 5; 95% confidence interval: 10, 32); and off class I/III AADs/electrocardioversion/re-TCA was 52% (SD: 7; 95% confidence interval: 0.83, 8.02). At 8 years, the predicted prevalence of patients in SR was 87% and 53% were off class I/III AADs/electrocardioversion/re-TCA. The recurrent arrhythmia was AF in all patients except 2, who had atypical atrial flutter (4%). No predictors of AF recurrence were identified. At the last follow-up, 76% of the patients showed European Heart Rhythm Association class I. No strokes or thromboembolic events were documented and 76% of the subjects were off anticoagulation therapy. CONCLUSIONS Despite a considerable AF recurrence rate, our single-centre, long-term outcome of surgical PVI showed encouraging data, with the majority of patients remaining in SR, although many of them were on antiarrhythmic therapy.


Respiration ◽  
2021 ◽  
pp. 1-8
Author(s):  
Karin Sanders ◽  
Karin Klooster ◽  
Lowie E.G.W. Vanfleteren ◽  
Guy Plasqui ◽  
Anne-Marie Dingemans ◽  
...  

<b><i>Background:</i></b> Hypermetabolism and muscle wasting frequently occur in patients with severe emphysema. Improving respiratory mechanics by bronchoscopic lung volume reduction (BLVR) might contribute to muscle maintenance by decreasing energy requirements and alleviating eating-related dyspnoea. <b><i>Objective:</i></b> The goal was to assess the impact of BLVR on energy balance regulation. <b><i>Design:</i></b> Twenty emphysematous subjects participated in a controlled clinical experiment before and 6 months after BLVR. Energy requirements were assessed: basal metabolic rate (BMR) by ventilated hood, total daily energy expenditure (TDEE) by doubly labelled water, whole body fat-free mass (FFM) by deuterium dilution, and physical activity by accelerometry. Oxygen saturation, breathing rate, and heart rate were monitored before, during, and after a standardized meal via pulse oximetry and dyspnoea was rated. <b><i>Results:</i></b> Sixteen patients completed follow-up, and among those, 10 patients exceeded the minimal clinically important difference of residual volume (RV) reduction. RV was reduced with median (range) 1,285 mL (−2,430, −540). Before BLVR, 90% of patients was FFM-depleted despite a normal BMI (24.3 ± 4.3 kg/m<sup>2</sup>). BMR was elevated by 130%. TDEE/BMR was 1.4 ± 0.2 despite a very low median (range) daily step count of 2,188 (739, 7,110). Following BLVR, the components of energy metabolism did not change significantly after intervention compared to before intervention, but BLVR treatment decreased meal-related dyspnoea (4.1 vs. 1.7, <i>p</i> = 0.019). <b><i>Conclusions:</i></b> Impaired respiratory mechanics in hyperinflated emphysematous patients did not explain hypermetabolism. <b><i>Clinical Trial Registry Number:</i></b> NCT02500004 at www.clinicaltrial.gov.


Lupus ◽  
2019 ◽  
Vol 29 (1) ◽  
pp. 83-91
Author(s):  
G Vajgel ◽  
C B L Oliveira ◽  
D M N Costa ◽  
M A G M Cavalcante ◽  
L M Valente ◽  
...  

Objective We analyzed baseline and follow-up characteristics related to poorer renal outcomes in a Brazilian cohort of admixture race patients with lupus nephritis. Methods Overall, 280 outpatients with a diagnosis of systemic lupus erythematosus and previous kidney biopsy of lupus nephritis were recruited from August 2015 to December 2018 and had baseline laboratory and histologic data retrospectively analyzed; patients were then followed-up and data were recorded. The main outcome measure was the estimated glomerular filtration rate at last follow-up. Secondary analyses assessed the impact of initial kidney histology and treatment in long-term kidney survival. Results Median duration of lupus nephritis was 60 months (interquartile range: 27–120); 40 (14.3%) patients presented progressive chronic kidney disease (estimated glomerular filtration rate <30 and ≥10 ml/min/1.73 m2) or end-stage kidney disease at last visit. Adjusted logistic regression analysis showed that class IV lupus nephritis (odds ratio 14.91; 95% confidence interval 1.77–125.99; p = 0.01) and interstitial fibrosis ≥25% at initial biopsy (odds ratio 5.87; 95% confidence interval 1.32–26.16; p = 0.02), lack of complete or partial response at 12 months (odds ratio 16.3; 95% confidence interval 3.74–71.43; p < 0.001), and a second renal flare (odds ratio 4.49; 95% confidence interval 1.10–18.44; p = 0.04) were predictors of progressive chronic kidney disease. In a Kaplan-Meier survival curve we found that class IV lupus nephritis and interstitial fibrosis ≥25% were significantly associated with end-stage kidney disease throughout follow-up (hazard ratio 2.96; 95% confidence interval 1.3–7.0; p = 0.036 and hazard ratio 4.96; 95% confidence interval 1.9–12.9; p < 0.0001, respectively). Conclusion In this large cohort of admixture race patients, class IV lupus nephritis and chronic interstitial damage at initial renal biopsy together with non-response after 1 year of therapy and relapse were associated with worse long-term renal outcomes.


2005 ◽  
Vol 33 (8) ◽  
pp. 1220-1223 ◽  
Author(s):  
Joseph R. Carney ◽  
Timothy S. Mologne ◽  
Michael Muldoon ◽  
Jay S. Cox

Background Few published articles exist reporting the long-term evaluation of the Roux-Elmslie-Trillat procedure. Purpose To assess the long-term effect of the Roux-Elmslie-Trillat procedure in preventing recurrent subluxation and dislocation of the patella. Study Design Case series; Level of evidence, 4. Methods Eighteen patients who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella were identified from a group previously evaluated at a mean follow-up of 3 years. The prevalence of recurrent subluxation or dislocation at a mean follow-up of 26 years was compared with the prevalence reported at the mean follow-up of 3 years. Although not the focus of this study, Cox functional scores were obtained from the smaller group and compared with the results at the 3-year follow-up. Results Seven percent (95% confidence interval, 0.00-0.32) of the patients had recurrent subluxation at 26 years compared with 7% (95% confidence interval, 0.03-0.13) of the study population reported at 3 years (P = 1.00). Fifty-four percent (95% confidence interval, 0.27-0.79) rated their affected knee as good or excellent at 26 years compared with 73% (95% confidence interval, 0.64-0.81) of the larger study population reported at 3 years (P = .14). Conclusion The prevalence of recurrent subluxation and dislocation in patients with patellofemoral malalignment who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella is similar at 3 and 26 years after the procedure. The long-term functional status of the affected knee in patients who underwent the Roux-Elmslie-Trillat procedure declined.


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