scholarly journals Nitric oxide-mediated vascular function in sepsis using passive leg movement as a novel assessment: a cross-sectional study

2016 ◽  
Vol 120 (9) ◽  
pp. 991-999 ◽  
Author(s):  
Ashley D. Nelson ◽  
Matthew J. Rossman ◽  
Melissa A. Witman ◽  
Zachary Barrett-O'Keefe ◽  
H. Jonathan Groot ◽  
...  

Post-cuff occlusion flow-mediated dilation (FMD) is a proposed indicator of nitric oxide (NO) bioavailability and vascular function. FMD is reduced in patients with sepsis and may be a marker of end organ damage and mortality. However, FMD likely does not solely reflect NO-mediated vasodilation, is technically challenging, and often demonstrates poor reproducibility. In contrast, passive leg movement (PLM), a novel methodology to assess vascular function, yields a hyperemic response that is predominately NO-dependent, reproducible, and easily measured. This study evaluated PLM as an approach to assess NO-mediated vascular function in patients with sepsis. We hypothesized that PLM-induced hyperemia, quantified by the increase in leg blood flow (LBF), would be attenuated in sepsis. In a cross-sectional study, 17 subjects in severe sepsis or septic shock were compared with 16 matched healthy controls. Doppler ultrasound was used to assess brachial artery FMD and the hyperemic response to PLM in the femoral artery. FMD was attenuated in septic compared with control subjects (1.1 ± 1.7% vs. 6.8 ± 1.3%; values are means ± SD). In terms of PLM, baseline LBF (196 ± 33 ml/min vs. 328 ± 20 ml/min), peak change in LBF from baseline (133 ± 28 ml/min vs. 483 ± 86 ml/min), and the LBF area under the curve (16 ± 8.3 vs. 143 ± 33) were all significantly attenuated in septic subjects. Vascular function, as assessed by both FMD and PLM, is attenuated in septic subjects compared with controls. These data support the concept that NO bioavailability is attenuated in septic subjects, and PLM appears to be a novel and feasible approach to assess NO-mediated vascular function in sepsis.

2017 ◽  
Vol 123 (6) ◽  
pp. 1468-1476 ◽  
Author(s):  
Ryan M. Broxterman ◽  
Joel D. Trinity ◽  
Jayson R. Gifford ◽  
Oh Sung Kwon ◽  
Andrew C. Kithas ◽  
...  

The assessment of passive leg movement (PLM)-induced leg blood flow (LBF) and vascular conductance (LVC) is a novel approach to assess vascular function that has recently been simplified to only a single PLM (sPLM), thereby increasing the clinical utility of this technique. As the physiological mechanisms mediating the robust increase in LBF and LVC with sPLM are unknown, we tested the hypothesis that nitric oxide (NO) is a major contributor to the sPLM-induced LBF and LVC response. In nine healthy men, sPLM was performed with and without NO synthase inhibition by intra-arterial infusion of NG-monomethyl-l-arginine (l-NMMA). Doppler ultrasound and femoral arterial pressure were used to determine LBF and LVC, which were characterized by the peak change (ΔLBFpeak and ΔLVCpeak) and area under the curve (LBFAUC and LVCAUC). l-NMMA significantly attenuated ΔLBFpeak [492 ± 153 (l-NMMA) vs. 719 ± 238 (control) ml/min], LBFAUC [57 ± 34 (l NMMA) vs. 147 ± 63 (control) ml], ΔLVCpeak [4.7 ± 1.1 (l-NMMA) vs. 8.0 ± 3.0 (control) ml·min−1·mmHg−1], and LVCAUC [0.5 ± 0.3 (l-NMMA) vs. 1.6 ± 0.9 (control) ml/mmHg]. The magnitude of the NO contribution to LBF and LVC was significantly correlated with the magnitude of the control responses ( r = 0.94 for ΔLBFpeak, r = 0.85 for LBFAUC, r = 0.94 for ΔLVCpeak, and r = 0.95 for LVCAUC). These data establish that the sPLM-induced hyperemic and vasodilatory response is predominantly (~65%) NO-mediated. As such, sPLM appears to be a promising, simple, in vivo assessment of NO-mediated vascular function and NO bioavailability. NEW & NOTEWORTHY Passive leg movement (PLM), a novel assessment of vascular function, has been simplified to a single PLM (sPLM), thereby increasing the clinical utility of this technique. However, the role of nitric oxide (NO) in mediating the robust sPLM hemodynamic responses is unknown. This study revealed that sPLM induces a hyperemic and vasodilatory response that is predominantly NO-mediated and, as such, appears to be a promising simple, in vivo, clinical assessment of NO-mediated vascular function and, therefore, NO bioavailability.


2017 ◽  
Vol 1 (3) ◽  
pp. 10-16
Author(s):  
Prakashkumar Kyada ◽  
Kunal Jadhav ◽  
T. K. Biswas ◽  
Varshil Mehta ◽  
Sojib Bin Zaman

Objective: Hypertension is one of the common risk factors for cardiovascular and cerebrovascular diseases/disorders A developing country like India faces the double burden of communicable and non-communicable diseases; of the which, hypertension is the most important treatable cause of mortality and morbidity with loss of functional capacity and decline in the quality of life. Aim: To study the prevalence of end organ damage in the hypertensive geriatric age group. Method: The present study was a cross sectional study, conducted in 150 elderly patients admitted in MGM Hospital, Navi Mumbai, India with the diagnosis of stage I or II hypertension from 2011 to 2013. Results: Data analysis of the present study showed that 68% of elderly population aged between 60 to 69 years were suffering from hypertension. Compared to males, females had a higher rate of target organ damage. This study found that out of all patients with total end organ damage, 54.6 % had CVS complications, 15.7 % had hypertensive retinopathy, 25.9 % and 18.51 had raised creatinine and proteinuria respectively. 19.4 % had cerebrovascular accident (CVA) complications. Among Cardiovascular related complications Coronary artery disease (CAD) was found in 21 patients, out of them 7 had Congestive cardiac Failure (CCF). Left Ventricular Hypertrophy (LVH) was the most common complication and seen in 38 patients. 13.8 % patients had Regional Wall Motion Abnormality (RWMA) Conclusion: The present study concluded that Isolated Systolic Hypertension (ISH) is the commonest type of hypertension in geriatric age group. This study concluded that the most common risk factors of HTN in the elderly are sedentary life style, dyslipidemia and extra salt intake while the most common end organ damage was observed to be Left Ventricular Hypertrophy followed by renal dysfunction. Keywords:  Hypertension,  Isolated Systolic Hypertension, Dyslipidemia.


2018 ◽  
Vol 3 (2) ◽  
pp. 11
Author(s):  
Yadul Ulya ◽  
Aryadi Arsyad ◽  
Saidah Syamsuddin

Anemia saat hamil berefek buruk bagi ibu maupun janin, karena dapat mengurangi suplai oksigen pada metabolisme ibu akibat kekurangan kadar hemoglobin untuk mengikat oksigen, dan peran hemoglobin sebagai pengikat nitric oxide dapat menyebabkan vasokontriksi dan mempengaruhi pengiriman oksigen. Tujuannya untuk mengetahui perbedaan kadar nitric oxide pada ibu hamil trimester 1 dengan anemia dan tidak anemia. Desain penelitian cross sectional study dengan masing-masing 35 ibu hamil trimester 1 yang anemia dan tidak anemia dengan teknik consecutive sampling. Hasil penelitian menunjukkan rata-rata kadar nitric oxide pada ibu hamil trimester 1 yang anemia lebih tinggi (128,8μmol/L) dibandingkan yang tidak anemia (89,1μmol/L) nilai p=0,008. Ibu hamil trimester 1 yang anemia kemungkinan 3,692 kali memiliki resiko mengalami peningkatan kadar nitric oxide dibandingkan yang tidak anemia dengan cut off point 92,86μmol/L. Disimpulkan, kadar nitric oxide lebih tinggi pada ibu hamil trimester 1 yang anemia dan memiliki resiko terjadi peningkatan kadar nitric oxide pada ibu hamil trimester 1 dengan anemia sebesar 3,962 kali.


2019 ◽  
Vol 7 (1) ◽  
pp. 96-101
Author(s):  
Maria Estela Karolina ◽  
Armaidi Darmawan ◽  
Wahyu Indah Dewi Aurora

Abstract Background: Cigarette smoke can affect macrophage metabolism by activating macrophages to release leukotrien B4, IL-8 and TNFα which lead to increased production of superoxide (O2-) and H2O2 and also cause oxidative damage to macromolecules such as lipids, proteins, DNA that can eliminate antioxidants and form free radicals such as Nitric Oxide (NO). NO has an important contribution in the occurrence of infection where NO will be produced more by iNOS. Methods: This study is a cross sectional study with a sample of samples taken in total sampling from medical students of Jambi University as many as 22 people with smokers and 22 non-smokers. Conducted NO examination by using microplate reader on wave 595. Research data obtained then tested by statistical analysis with mann whitney and wilcoxon test. Results : NO levels in smokers were higher than nonsmoker group NO levels. Based on normality test data with Mann Whitney obtained significant difference between both groups value of sig 0.030. Furthermore, Wilcoxon analysis. The result of wilcoxon analysis shows statistic test output where sig (<0,05). Conclusion : NO levels in the smoker group were higher than in the nonsmokers group. NO levels between smokers and nonsmokers were significantly different. Keywords : Smokers, non-smokers, nitric oxide   Abstrak Pendahuluan : Asap rokok dapat mempengaruhi metabolisme makrofag dengan mengaktifkan makrofag untuk melepaskan leukotrien B4, IL-8 dan TNFα yang menyebabkan meningkatnya produksi superoksida (O2-) dan H2O2 dan juga menyebabkan kerusakan oksidatif makromolekul seperti lipid, protein, DNA yang dapat   menghilangkan  antioksidan  serta  membentuk radikal  bebas seperti Nitrit  Oxide  (NO).  NO mempunyai kontribusi yang penting dalam terjadinya infeksi dimana NO akan diproduksi lebih banyak oleh iNOS. Metode : Penelitian ini merupakan penelitian cross sectional dengan sampel penelitian yang diambil secara total sampling dari mahasiswa kedokteran Universitas Jambi sebanyak 22 orang dengan perokok dan 22 orang bukan perokok. Dilakukan pemeriksaan NO dengan menggunakan microplate reader pada gelombang 595. Data penelitian yang di dapatkan kemudian di uji dengan analisis statistic dengan uji mann whitney dan wilcoxon. Hasil : Kadar NO pada perokok lebih tinggi dibandingkan dengan kadar NO kelompok bukan perokok. Berdasarkan uji normalitas data dengan Mann whitney diperoleh perbedaan yang bermakna diantara kedua kelompok nilai sig 0.030. Selanjutnya dilakukan Analisis Wilcoxon. Hasil analisis wilcoxon menunjukkan output test statistic dimana sig (<0,05). Kesimpulan  :  Kadar  NO  pada  kelompok  perokok  lebih  tinggi  dibandingkan  dengan  kelompok  bukan perokok. Kadar NO antara kelompok perokok dan bukan perokok terdapat perbedaan yang signifikan. Kata Kunci : Perokok, bukan perokok, Nitric Oxide


2021 ◽  
Vol 7 (4) ◽  
pp. 318-319
Author(s):  
Laura Herranz ◽  
Juliana Gurgel da Silveira ◽  
Luis Filipe Lannes Trocado ◽  
Anna Luiza Alvaraes ◽  
Juliana Fittipaldi

Author(s):  
Joel D. Trinity ◽  
Oh Sung Kwon ◽  
Ryan M. Broxterman ◽  
Jayson R. Gifford ◽  
Andrew C. Kithas ◽  
...  

Passive leg movement (PLM) evokes a robust and predominantly nitric oxide (NO)-mediated increase in blood flow that declines with age and disease. Consequently, PLM is becoming increasingly accepted as a sensitive assessment of endothelium-mediated vascular function. However, a substantial PLM-induced hyperemic response is still evoked despite NO synthase (NOS) inhibition. Therefore, in 9 young healthy men (25±4 yrs), this investigation aimed to determine if the combination of two potent endothelium-dependent vasodilators, specifically prostaglandin (PG) and endothelium-derived hyperpolarizing factor (EDHF), account for the remaining hyperemic response to the two variants of PLM, PLM (60 movements) and single PLM (sPLM, 1 movement) when NOS is inhibited. The leg blood flow (LBF, Doppler ultrasound) response to PLM and sPLM following the intra-arterial infusion of NG-monomethyl L-arginine (L-NMMA), to inhibit NOS, was compared to the combined inhibition of NOS, cyclooxygenase (COX), and cytochrome P450 (CYP450) by L-NMMA, ketorolac tromethamine (KET), and fluconazole (FLUC), respectively. NOS inhibition attenuated the overall LBF (LBFAUC) response to both PLM (control: 456±194, L-NMMA: 168±127 ml, p<0.01) and sPLM (control: 185±171, L-NMMA: 62±31 ml, p=0.03). The combined inhibition of NOS, COX, and CYP450 (i.e. L-NMMA+KET+FLUC) did not further attenuate the hyperemic responses to PLM (LBFAUC: 271±97 ml, p>0.05) or sPLM (LBFAUC: 72±45 ml, p>0.05). Therefore, PG and EDHF do not collectively contribute to the non-NOS-derived NO-mediated, endothelium-dependent, hyperemic response to either PLM or sPLM in healthy young men. These findings add to the mounting evidence and understanding of the vasodilatory pathways assessed by the PLM and sPLM vascular function tests.


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