Journal articles: 'Hemodynamic loading'

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Fujimoto, Naoki, Barry A. Borlaug, Gregory D. Lewis, Jeffrey L. Hastings, Keri M. Shafer, Paul S. Bhella, Graeme Carrick-Ranson, and Benjamin D. Levine. "Hemodynamic Responses to Rapid Saline Loading." Circulation 127, no. 1 (January 2013): 55–62. http://dx.doi.org/10.1161/circulationaha.112.111302.

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Granton, John. "Cardiopulmonary Interactions during Positive Pressure Ventilation." Canadian Respiratory Journal 3, no. 6 (1996): 380–85. http://dx.doi.org/10.1155/1996/253907.

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Positive pressure ventilation (PPV) may lead to significant hemodynamic alterations. The cardiocirculatory effects of PPV occur through alterations in the loading conditions of the right and left ventricle and are mediated by changes in intrathoracic pressures and in lung volume. However, the net effect of PPV on cardiac output and hemodynamics is not always predictable. PPV may lead to either a decrease or an increase in cardiac performance. The cardiac consequences of PPV are also dependent on baseline loading conditions and contractile function of the heart.

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Gefke, Maria, Niels Juel Christensen, Per Bech, Erik Frandsen, Morten Damgaard, Ali Asmar, and Peter Norsk. "Hemodynamic responses to mental stress during salt loading." Clinical Physiology and Functional Imaging 37, no. 6 (April 6, 2016): 688–94. http://dx.doi.org/10.1111/cpf.12360.

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Rissanen, Joonas Antero, Keijo Häkkinen, Jari Antero Laukkanen, and Arja Häkkinen. "Acute Hemodynamic Responses to Combined Exercise and Sauna." International Journal of Sports Medicine 41, no. 12 (June 29, 2020): 824–31. http://dx.doi.org/10.1055/a-1186-1716.

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AbstractThis study investigated acute hemodynamic, plasma volume and immunological responses to four loading protocols: sauna only, and sauna after endurance, strength or combined endurance and strength exercise. Twenty-seven healthy, slightly prehypertensive men (age 32.7±6.9 years) were measured at PRE, MID (after exercise), POST, POST30min and POST24h. The measurements consisted systolic and diastolic blood pressure, heart rate, body temperature and concentrations of high-sensitive C-reactive protein, white blood cells and plasma volume measurements. Endurance+sauna showed significant decreases in systolic blood pressure at POST (–8.9 mmHg), POST30min (–11.0 mmHg) and POST24h (–4.6 mmHg). At POST30min, significant decreases were also observed in sauna (–4.3 mmHg) and combined+sauna (–7.5 mmHg). Diastolic blood pressure decreased significantly from -5.4 to –3.9 mmHg at POST in all loadings. Plasma volume decreased significantly at MID in all exercise loadings and at POST in endurance+sauna and strength+sauna. Plasma volume increased significantly (p < 0.01) in endurance+sauna and combined+sauna at POST24h. White blood cells increased following all exercise+sauna loadings at MID, POST and POST30min, whereas high sensitive C-reactive protein showed no changes at any measurement point. The combination of endurance exercise and sauna showed the greatest positive effects on blood pressure. Both loadings including endurance exercise increased plasma volume on the next day.

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Ramo, P., R. Kettunen, and L. Hirvonen. "Hemodynamic effects of endurance training on canine left ventricle." American Journal of Physiology-Heart and Circulatory Physiology 252, no. 1 (January 1, 1987): H7—H13. http://dx.doi.org/10.1152/ajpheart.1987.252.1.h7.

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To investigate the effects of endurance training on myocardial performance seven beagle dogs (exercise group, EG) were trained by treadmill running for 6–7 wk. Before and after experimental period the EG and control group (CG, n = 7) underwent a standard submaximal exercise test (SMT), and hemodynamic status was checked during anesthesia by catheterization technique exposing the animals to different loadings: pacing, volume loading, and isoproterenol infusion. The increase of heart rate during SMT was about 30 beats/min less in the EG than in the CG. A highly linear relationship between stroke work and end-diastolic volume was observed within the groups (for EG r = 0.953, for CG r = 0.846), but the slope of the regression line obtained for EG appeared to be significantly (P less than 0.001) greater. In EG isoproterenol induced increases in end-diastolic (27%), end-systolic (37%), and stroke volumes (19%), but, on the contrary, decreases of these volumes in CG (19, 15, and 22%, respectively); ejection fraction remained unchanged for both EG and CG. Ventricular stroke work was significantly greater in EG. Systemic vascular resistance decreased in EG in every loading test. The results indicate an improved pump performance, which is related not only to the heterometric autoregulatory adjustments, but also to extracardial adaptations.

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Sedmera, David. "HLHS: Power of the Chick Model." Journal of Cardiovascular Development and Disease 9, no. 4 (April 11, 2022): 113. http://dx.doi.org/10.3390/jcdd9040113.

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Background: Hypoplastic left heart syndrome (HLHS) is a rare but deadly form of human congenital heart disease, most likely of diverse etiologies. Hemodynamic alterations such as those resulting from premature foramen ovale closure or aortic stenosis are among the possible pathways. Methods: The information gained from studies performed in the chick model of HLHS is reviewed. Altered hemodynamics leads to a decrease in myocyte proliferation causing hypoplasia of the left heart structures and their functional changes. Conclusions: Although the chick phenocopy of HLHS caused by left atrial ligation is certainly not representative of all the possible etiologies, it provides many useful hints regarding the plasticity of the genetically normal developing myocardium under altered hemodynamic loading leading to the HLHS phenotype, and even suggestions on some potential strategies for prenatal repair.

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Rogers, Aaron J., Ramaswamy Kannappan, Hadil Abukhalifeh, Mohammed Ghazal, Jessica M. Miller, Ayman El-Baz, Vladimir G. Fast, and Palaniappan Sethu. "Hemodynamic Stimulation Using the Biomimetic Cardiac Tissue Model (BCTM) Enhances Maturation of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes." Cells Tissues Organs 206, no. 1-2 (2018): 82–94. http://dx.doi.org/10.1159/000496934.

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Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs) hold great promise for cardiovascular disease modeling and regenerative medicine. However, these cells are both structurally and functionally immature, primarily due to their differentiation into cardiomyocytes occurring under static culture which only reproduces biomolecular cues and ignores the dynamic hemodynamic cues that shape early and late heart development during cardiogenesis. To evaluate the effects of hemodynamic stimuli on hiPSC-CM maturation, we used the biomimetic cardiac tissue model to reproduce the hemodynamics and pressure/volume changes associated with heart development. Following 7 days of gradually increasing stimulation, we show that hemodynamic loading results in (a) enhanced alignment of the cells and extracellular matrix, (b) significant increases in genes associated with physiological hypertrophy, (c) noticeable changes in sarcomeric organization and potential changes to cellular metabolism, and (d) a significant increase in fractional shortening, suggestive of a positive force frequency response. These findings suggest that culture of hiPSC-CMs under conditions that accurately reproduce hemodynamic cues results in structural organization and molecular signaling consistent with organ growth and functional maturation.

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Napoli, Anthony M. "Physiologic and Clinical Principles behind Noninvasive Resuscitation Techniques and Cardiac Output Monitoring." Cardiology Research and Practice 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/531908.

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Clinical assessment and vital signs are poor predictors of the overall hemodynamic state. Optimal measurement of the response to fluid resuscitation and hemodynamics has previously required invasive measurement with radial and pulmonary artery catheterization. Newer noninvasive resuscitation technology offers the hope of more accurately and safely monitoring a broader range of critically ill patients while using fewer resources. Fluid responsiveness, the cardiac response to volume loading, represents a dynamic method of improving upon the assessment of preload when compared to static measures like central venous pressure. Multiple new hemodynamic monitors now exist that can noninvasively report cardiac output and oxygen delivery in a continuous manner. Proper assessment of the potential future role of these techniques in resuscitation requires understanding the underlying physiologic and clinical principles, reviewing the most recent literature examining their clinical validity, and evaluating their respective advantages and limitations.

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Ogilvie, Leslie M., Brittany A. Edgett, Jason S. Huber, Mathew J. Platt, Hermann J. Eberl, Sohrab Lutchmedial, Keith R. Brunt, and Jeremy A. Simpson. "Hemodynamic assessment of diastolic function for experimental models." American Journal of Physiology-Heart and Circulatory Physiology 318, no. 5 (May 1, 2020): H1139—H1158. http://dx.doi.org/10.1152/ajpheart.00705.2019.

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Traditionally, the evaluation of cardiac function has focused on systolic function; however, there is a growing appreciation for the contribution of diastolic function to overall cardiac health. Given the emerging interest in evaluating diastolic function in all models of heart failure, there is a need for sensitivity, accuracy, and precision in the hemodynamic assessment of diastolic function. Hemodynamics measure cardiac pressures in vivo, offering a direct assessment of diastolic function. In this review, we summarize the underlying principles of diastolic function, dividing diastole into two phases: 1) relaxation and 2) filling. We identify parameters used to comprehensively evaluate diastolic function by hemodynamics, clarify how each parameter is obtained, and consider the advantages and limitations associated with each measure. We provide a summary of the sensitivity of each diastolic parameter to loading conditions. Furthermore, we discuss differences that can occur in the accuracy of diastolic and systolic indices when generated by automated software compared with custom software analysis and the magnitude each parameter is influenced during inspiration with healthy breathing and a mild breathing load, commonly expected in heart failure. Finally, we identify key variables to control (e.g., body temperature, anesthetic, sampling rate) when collecting hemodynamic data. This review provides fundamental knowledge for users to succeed in troubleshooting and guidelines for evaluating diastolic function by hemodynamics in experimental models of heart failure. Listen to this article’s corresponding podcast at https://ajpheart.podbean.com/e/assessment-of-diastolic-function/ .

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Losser, Marie-Reine, Catherine Bernard, Jean-Louis Beaudeux, Christophe Pison, and Didier Payen. "Glucose modulates hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide in rabbits." Journal of Applied Physiology 83, no. 5 (November 1, 1997): 1566–74. http://dx.doi.org/10.1152/jappl.1997.83.5.1566.

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Losser, Marie-Reine, Catherine Bernard, Jean-Louis Beaudeux, Christophe Pison, and Didier Payen. Glucose modulates hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide in rabbits. J. Appl. Physiol. 83(5): 1566–1574, 1997.—Glucose is important for vascular and immunocompetent cell functions. We hypothesized that modifications in glucose metabolism (normal feeding, 24-h fasting, glucose loading) may influence the hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide administration (LPS; 600 μg/kg iv) in rabbits. Aortic (ABFV), hepatic artery (HABFV), and portal vein blood flow velocities (PVBFV) (pulsed Doppler), plasma tumor necrosis factor (TNF) and nitrites were measured. Fasting depleted hepatic glycogen content, and intraportal glucose load (2 g/kg) partially restored it. LPS induced a similar hypotension (−20%, P < 0.05) in three groups of animals. In fed animals, systemic vasoconstriction occured with low ABFV and PVBFV (−40%, P < 0.05), together with lactacidemia and hyperglycemia. In fasted animals, ABFV and PVBFV were maintained, without metabolic acidosis or hyperglycemia. Glucose loading induced hemodynamic and metabolic patterns comparable to those observed in fed animals, although significantly more severe. TNF release was amplified fourfold by glucose loading, with no impact on nitrite levels. In conclusion, glucose metabolism interferes with hemodynamic, metabolic, and inflammatory responses to LPS.

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Ahamad Masoori, Tahir, Kumkum Gupta, Salony Agarwal, Manoranjan Bansal, Azka Zuberi, and Abdul Samad. "Clinical efficacy of dexmedetomidine in two different doses to attenuate the hemodynamic changes during laparoscopic cholecystectomy." International Journal of Research in Medical Sciences 6, no. 3 (February 22, 2018): 959. http://dx.doi.org/10.18203/2320-6012.ijrms20180623.

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Background: Laryngoscopy and laparoscopy lead to predictable hemodynamic changes. Dexmedetomidine is selective 2 agonist with dose dependent sedation, sympatholysis and analgesia, hence could provide stable hemodynamics during laparoscopic surgeries. The present study was aimed to compare the clinical efficacy of dexmedetomidine infusion in two different doses to attenuate the hemodynamic variations during laparoscopic cholecystectomy.Methods: Total 60 adult patients of ASA physical status I and II of both gender, scheduled for elective laparoscopic cholecystectomy, were randomly allocated into two groups of 30 patients. All patients were infused with loading dose of dexmedetomidine (1µg/kg) before induction. Patients of Group 1 received maintenance infusion of dexmedetomidine in doses of 0.3µg/kg/h and patients of Group 2 received maintenance infusion of dexmedetomidine in doses of 0.6µg/kg/h, continued till the end of surgery. Heart rate and blood pressure were recorded preoperatively, after dexmedetomidine administration, after induction, intubation, after creation of pneumoperitoneum and postoperatively. Intraoperative changes in heart rate and blood pressure were noted as primary variables and dexmedetomidine related side effects were noted as secondary outcomes, for statistical analysis.Results: The hemodynamic responses were attenuated in patients of both groups after laryngoscopy, intubation and creation of pneumoperitoneum but patients of Group 2 (0.6µg/kg/h) showed more stability in hemodynamics. The difference between the group was statistically significant (p value=0.001). No any evident complication or side effects occurred.Conclusions: Dexmedetomidine infusion was effective for attenuating the hemodynamic changes due to laryngoscopy and laparoscopy but were better with maintenance infusion of dexmedetomidine in dose of 0.6µg/kg/h.

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Dawkins, Tony G., Bryony A. Curry, Aimee L. Drane, Rachel N. Lord, Cory Richards, Megan Brown, Christopher J. A. Pugh, et al. "Stimulus-specific functional remodeling of the left ventricle in endurance and resistance-trained men." American Journal of Physiology-Heart and Circulatory Physiology 319, no. 3 (September 1, 2020): H632—H641. http://dx.doi.org/10.1152/ajpheart.00233.2020.

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Training-specific functional remodeling of the LV in response to different loading conditions has been recently suggested, but not experimentally tested in the same group of individuals. Our data provide novel evidence of a dichotomous, training-specific LV adaptive response to hemodynamic pressure or volume loading.

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Aggarwal, Akanksha, and Divya Mahajan. "Comparison of Dexmedetomidine with Fentanyl and Pentazocine – Promethazine in patients undergoing dilation and curettage in monitored anesthesia care." Indian Journal of Clinical Anaesthesia 8, no. 3 (September 15, 2021): 396–400. http://dx.doi.org/10.18231/j.ijca.2021.076.

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Dilatation and curettage (D and C) is an essential and common minor surgery in obstetrics and gynecology. Sedation, hypnosis and analgesia are used in combination for such short procedures. These days conscious sedation is provided to patients for day care surgeries which includes analgesia, sedation and anxiolysis while rapid recovery is ensured without side effects. Dexmedetomidine is a highly selective alpha-2 agonist that provides anxiolysis and conscious sedation without respiratory depression. It was to study the effect of dexemedetomidine with fentanyl versus Pentazocine with promethazine on hemodynamic stability and recovery during sedation in dilatation and curettage procedure. The comparison included the hemodynamic data and recovery time. The effect of the drugs on hemodynamics and monitoring the occurrence of any complication were also done. In our study, 50 patients were randomly divided into 2 equal groups; group DF received dexmedetomidine loading dose 1 μg/kg over 10 min and followed by 0.5 μg/kg/hr infusion till completion of surgery and group PP received pentazocine 0.5 mg/kg (max 30mg) and Promethazine 12.5 mg slow intravenous Bolus. Dexmedetomidine is a safe drug which provides good hemodynamics and less recovery time. It also exerts sedative and analgesic effects without respiratory depression unlike most analgesic/sedative drugs, such as ketamine, pentazocine and benzodiazepines. This study demonstrates that dexmedetomidine is a safe drug with good hemodynamic and recovery profile. Dexmedetomidine administration showed better preservation of MAP and SpO2.

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Mercat, Alain, Jean-Luc Diehl, Guy Meyer, Jean-Louis Teboul, and Herve Sors. "Hemodynamic effects of fluid loading in acute massive pulmonary embolism." Critical Care Medicine 27, no. 3 (March 1999): 540–44. http://dx.doi.org/10.1097/00003246-199903000-00032.

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Hagdorn, Quint A. J., Niek E. G. Beurskens, Thomas M. Gorter, Graziëlla Eshuis, Hans L. Hillege, George K. Lui, Scott R. Ceresnak, et al. "Sex differences in patients with repaired tetralogy of Fallot support a tailored approach for males and females: a cardiac magnetic resonance study." International Journal of Cardiovascular Imaging 36, no. 10 (May 30, 2020): 1997–2005. http://dx.doi.org/10.1007/s10554-020-01900-x.

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Abstract Purpose Substantial differences between sexes exist with respect to cardiovascular diseases, including congenital heart disease. Nevertheless, clinical decisions in the long-term follow-up of patients with repaired tetralogy of Fallot (rTOF) are currently based on unisex thresholds for cardiac magnetic resonance (CMR) measurements. This study aimed to assess whether sex differences exist in cardiac adaptation to hemodynamic loading conditions in patients with rTOF. Methods and Results This cross-sectional, two-center, combined pediatric and adult cohort included 320 rTOF patients (163 males, 51%) who underwent routine CMR. Despite similar age (median and interquartile range [m + IQR] 23.4 [15.2–34.4] years), surgical history, and hemodynamic loading, males with rTOF demonstrated higher biventricular CMR-derived volumes and masses, indexed for body surface area, compared to females (e.g. m + IQR right ventricular (RV) end-diastolic volume: males 123 [100–151] mL/m2, females 114 [94–131] mL/m2, P = 0.007). Sex-specific Z-scores of biventricular volumes and masses were similar for males and females. RV volumes and masses correlated with hemodynamic loading, but these relations did not differ between sexes. Biventricular ejection fraction (EF) appeared to be lower in male patients, compared to female patients (e.g. m + IQR RVEF: males 48 [43–54]%, females 52 [46–57]%, P < 0.001). Conclusion Indexed ventricular volumes and masses are higher in males with rTOF, compared to females, similar to the healthy population. RV hypertrophy and dilatation correlated to loading conditions similarly for both sexes. However, under comparable loading conditions, males demonstrated more severe functional impairment. These results indicate that sex-differences should no longer be ignored in treatment strategies, including timing of pulmonary valve replacement.

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D’Alto, Michele, Emanuele Romeo, Paola Argiento, Agostino Mattera Iacono, Serena Vettori, Antonella Riccardi, Yannick Allanore, et al. "Hemodynamic changes after acute fluid loading in patients with systemic sclerosis without pulmonary hypertension." Pulmonary Circulation 9, no. 1 (November 13, 2018): 204589401881608. http://dx.doi.org/10.1177/2045894018816089.

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A fluid challenge with a rapid infusion of saline helps to discriminate between pre- and post-capillary pulmonary hypertension (PH) and allows unmasking hidden post-capillary PH. Systemic sclerosis (SSc) patients may present with biventricular systolic and diastolic dysfunction. The aim of this study was to evaluate the hemodynamic changes of the pulmonary circulation in SSc patients without PH after a fluid challenge. Twenty-five SSc patients and 25 controls underwent right heart catheterization in basal conditions and after volume loading with saline infusion of 7 mL/kg over 5–10 min. At baseline, there was no difference in hemodynamics between SSc patients and controls. Rapid volume loading resulted in a significant increase in pressures and flows in both groups. Increases in right atrial pressure (3 ± 1 vs. 2 ± 1 mmHg, P = 0.03), mean pulmonary artery pressure (5 ± 1 vs. 3 ± 1 mmHg, P < 0.001), and pulmonary artery wedge pressure (PAWP; 5 ± 2 vs. 3 ± 1 mmHg, P < 0.001) were larger in SSc patients than in controls. Conversely, cardiac index (0.4 ± 0.2 vs. 0.6 ± 0.3 L/min/m2, P = 0.005) increased less in SSc patients than in controls. Pulmonary vascular resistance did not differ between groups before and after volume loading. Four SSc patients and only one of the controls reached a PAWP > 18 mmHg suggesting latent left heart failure. Even if differences are small and not diagnostic for heart failure, SSc patients without PH have a larger increase in pulmonary vascular pressures and a smaller increase in cardiac output than controls after an acute volume loading, probably due to subclinical left ventricular diastolic dysfunction.

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Ikram, Hemid, Clive J. S. Low, Ien G. Crozier, and Teresa M. Shirlow. "Hemodynamic effects of acute loading changes in aortic stenosis therapeutic implications." Journal of the American College of Cardiology 15, no. 2 (February 1990): A95. http://dx.doi.org/10.1016/0735-1097(90)92097-l.

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Kaptein, E. M. "Acute hemodynamic effects of levothyroxine loading in critically ill hypothyroid patients." Archives of Internal Medicine 146, no. 4 (April 1, 1986): 662–66. http://dx.doi.org/10.1001/archinte.146.4.662.

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Kaptein, Elaine M. "Acute Hemodynamic Effects of Levothyroxine Loading in Critically Ill Hypothyroid Patients." Archives of Internal Medicine 146, no. 4 (April 1, 1986): 662. http://dx.doi.org/10.1001/archinte.1986.00360160064008.

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Zaslavskaya, R. M., and T. N. Zhumabaeva. "Сomparative effectiveness of calcium antagonists of prolonged action in patients with stable angina pectoris." Clinical Medicine (Russian Journal) 100, no. 11-12 (January 18, 2023): 551–54. http://dx.doi.org/10.30629/0023-2149-2022-100-11-12-551-554.

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The article is devoted to investigation the comparative efficacy of therapy with drugs of calcium antagonists with prolong action — dilren and altiasem PP in old patients, suffering from ischemic heart disease, stable stenocardia 2–3 functional class. There were established more eﬃcacy of therapy with dilren then altiasem PP in the relation to clinical symptoms, hemodynamical parameters and their circadian chronostructure. These data manifested by more essential antianginal, antiischemic and vasodilated eﬀects of dilren then of altiasem PP. There were more essential the increase of tolerance to physical loading, promotion of pumping myocardial function under the inﬂuence of dilren and tendency to normalization in circadian organization of hemodynamic parameters.

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Duara, S., C. Suguihara, T. Gerhardt, and E. Bancalari. "Metabolic, hemodynamic, and ventilatory responses to respiratory load in sedated neonatal piglets." Journal of Applied Physiology 75, no. 1 (July 1, 1993): 181–84. http://dx.doi.org/10.1152/jappl.1993.75.1.181.

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Some neonatal species fail to develop the expected degree of hypercapnia during hypoventilation with mechanical loads. We studied 13 spontaneously breathing, sedated piglets (1–9 days old), grouped by age as young (< or = 3 day old) or old (> 3 day old). Baseline measurements of minute ventilation, arterial blood pressure (BP), cardiac output, and O2 consumption were repeated after continuous (inspiratory and expiratory) flow-resistive loading of 330 cmH2O.l-1 x s for 10 min. Older animals [n = 6, age 6.6 +/- 1.9 (SD) days, wt 1.99 +/- 0.5 kg] increased metabolic rate (9.8 +/- 1.4 to 10.5 +/- 1.3 ml.min-1 x kg-1, P < 0.01), whereas younger animals (n = 7, 2.6 +/- 0.6 days, 1.37 +2- 0.3 kg) invariably decreased metabolic rate with loading (9.7 +/- 1.6 to 7.9 +/- 2.6 ml.min-1 x kg-1); changes were different between groups (P < 0.02). Although ventilation decreased with loading in both groups (P < 0.01), younger animals showed a relatively greater fall from baseline values (38 vs. 27%). Despite differences in the degree of hypoventilation, arterial CO2 tension increased similarly in both groups (21%). BP increased (P < 0.01) with loading in older but not younger animals. We conclude that the decreased metabolic rate and limited hemodynamic response in younger piglets reflect an accomodative response to hypoventilation in contrast to that of older animals, which display an adult pattern of increased metabolic rate and BP with loaded breathing.

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Shagufta, Dr, and Dr Hitesha Gurtoo. "Effect of Different Doses of Dexmedetomidine on Hemodynamic Response During Laryngoscopy and Tracheal Intubation: A Comparative Prospective Study in GMC Jammu." International Journal of Research and Review 9, no. 8 (September 5, 2022): 884–93. http://dx.doi.org/10.52403/ijrr.20220878.

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Background: Our study was conceptualised to evaluate and compare the effects of two different doses of dexmedetomidine infusion after single loading dose not only for attenuation of hemodynamic response to laryngoscopy and intubation but also to evaluate the efficacy to reduce post-operative analgesic requirement and its effect on sedation score post-operatively. Methods: This prospective randomized study was conducted in the postgraduate Department of Anaesthesiology and Intensive care, Government Medical College, Jammu after getting approval from Institutional ethical committee. Around 120 patients of either sex ranging in age from 18 to 60 years, belonging to ASA physical status grade 1 and 2, scheduled for elective laparoscopic cholecystectomy under general anaesthesia with endotracheal intubation were enrolled for the study. Results: Dexmedetomidine infusion of 0.5 m g/kg /h after loading dose of 1 mg/kg resulted in stable, steady and smooth reduction in heart rate, and arterial blood pressure with no episode of severe hypotension or other adverse event. The total analgesic requirement in 24 hours in group D1 was 123.83±6.08 mg. The total analgesic requirement in 24 hours in group D2 was 83.72±4.28 mg. The difference between the two groups was statistically significant. Conclusion: Dexmedetomidine infusion of 0.5 mg/kg /h after loading dose of 1 mg/kg successfully maintained hemodynamic stability both intraoperatively and postoperatively. This dose increased the pain free period postoperatively, thus reducing the total analgesic requirement. Dexmedetomidine can, therefore, be considered an anaesthetic adjuvant in laparoscopic cholecystectomy and infusion dose of 0.5mg/kg/h is better than 0.2 mg/kg/ h after loading dose of 1 mg/kg. Keywords: Dexmedetomidine; hemodynamic response; tracheal intubation.

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Vanrenterghem, Y. F., R. K. Verberckmoes, L. M. Roels, and P. J. Michielsen. "Role of prostaglandins in protein-induced glomerular hyperfiltration in normal humans." American Journal of Physiology-Renal Physiology 254, no. 4 (April 1, 1988): F463—F469. http://dx.doi.org/10.1152/ajprenal.1988.254.4.f463.

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In six healthy male volunteers we studied the effect of indomethacin on the renal hemodynamic adaptations to an acute oral protein load. Control and protein loading studies without and with indomethacin were performed under sustained water diuresis. In the control studies without indomethacin, creatinine (CCr) and inulin clearance (CIn) remained stable and p-aminohippurate (PAH) clearance (CPAH) and kaliuresis slightly decreased while natriuresis progressively increased. Urinary prostaglandin E2 (PGE2) excretion remained stable. Indomethacin had no effect on these control values except on natriuresis and PGE2 excretion. After protein loading CCr, CIn, and CPAH progressively increased to reach a peak 2 h after protein intake. Natriuresis, kaliuresis, and urinary PGE2 excretion also increased significantly. After indomethacin the peak increase of CCr, CIn, and CPAH during the 2nd h was significantly blunted. Indomethacin had no effect on the increased sodium and potassium excretion. The increase of PGE2 excretion was significantly attenuated by indomethacin. The results presented suggest that renal prostaglandins play at least a partial role in the renal hemodynamic adaptations to protein loading.

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Brix, Bianca, Olivier White, Christian Ure, Gert Apich, Paul Simon, Andreas Roessler, and Nandu Goswami. "Hemodynamic Responses in Lower Limb Lymphedema Patients Undergoing Physical Therapy." Biology 10, no. 7 (July 10, 2021): 642. http://dx.doi.org/10.3390/biology10070642.

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Background: Lymphedema arises due to a malfunction of the lymphatic system, leading to extensive tissue swelling. Complete decongestive therapy (CDT), which is a physical therapy lasting for 3 weeks and includes manual lymphatic drainages (MLD), leads to fluid mobilization and increases in plasma volume. Here, we investigated hemodynamic responses induced by these fluid shifts due to CDT and MLD. Methods: Hemodynamic parameters were assessed continuously during a sit-to-stand test (5 min baseline, 5 min of standing, and 5 min of recovery). This intervention was repeated on days 1, 2, 7, 14, and 21 of CDT, before and after MLD. Volume regulatory hormones were assessed in plasma samples. Results: A total number of 13 patients took part in this investigation. Resting diastolic blood pressure significantly decreased over three weeks of CDT (p = 0.048). No changes in baseline values were shown due to MLD. However, MLD led to a significant decrease in heart rate during orthostatic loading over all epochs on therapy day 14, as well as day 21. Volume regulatory hormones did not show changes over lymphedema therapy. Conclusion: We did not observe any signs of orthostatic hypotension at rest, as well as during to CDT, indicating that lymphedema patients do not display an elevated risk of orthostatic intolerance. Although baseline hemodynamics were not affected, MLD has shown to have potential beneficial effects on hemodynamic responses to a sit-to-stand test in patients undergoing lymphedema therapy.

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Zuberi, Azka, Vaibhav Tiwary, Bhawana Rastogi, Kumkum Gupta, Abhishake Kumar, and Raza Farooqui. "Comparison of hemodynamic responses of intravenous dexmedetomidine and esmolol infusion during laparoscopic cholecystectomy." International Journal of Research in Medical Sciences 6, no. 4 (March 28, 2018): 1429. http://dx.doi.org/10.18203/2320-6012.ijrms20181309.

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Background: Laparoscopic cholecystectomy is one of the commonest surgery performed under general anesthesia in this set up but maintaining the hemodynamic stability is challenging in these patients. The present study was conducted to comparatively analyse the hemodynamic variations using intravenous dexmedetomidine and intravenous esmolol during laparoscopic cholecystectomy.Methods: Study was conducted on 90 adult patients aged 18-60 years, of ASA grade I or II of both gender, scheduled for laparoscopic cholecystectomy under general anesthesia. Patients were randomized into three groups of 30 patients each. Patients of Group A received esmolol infusion (loading: 1mg/kg and maintenance: 5-15µg/kg/min), patients of Group B received dexmedetomedine infusion (loading: 0.7µg/kg and maintenance: 0.4µg/kg/hr) and Group C (control group) received normal saline infusion. Patients were monitored for changes in heart rate, ECG, systemic blood pressure and EtCO2, at baseline, at 5 min and 10 min after giving study drug bolus, after induction, intubation, skin incision and CO2 insufflation. Thereafter, these changes were recorded at 15 min intervals till the end of surgery.Results: It was observed that perioperative use of dexmedetomidine and esmolol infusions maintained better hemodynamic stability as compared to the normal saline in control group. Though the patients in esmolol group showed less fluctuations in BP and HR (as compared to control group), but, stability was better in the patients of dexmedetomidine group at all-time intervals.Conclusions: Dexmedetomidine infusion was a better option for maintaining hemodynamic stability in comparison to emolol infusion during laparoscopic surgeries.

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Lakin, Robert, Ryan Debi, Sibao Yang, Nazari Polidovitch, Jack M. Goodman, and Peter H. Backx. "Differential negative effects of acute exhaustive swim exercise on the right ventricle are associated with disproportionate hemodynamic loading." American Journal of Physiology-Heart and Circulatory Physiology 320, no. 4 (April 1, 2021): H1261—H1275. http://dx.doi.org/10.1152/ajpheart.00603.2020.

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Acute exhaustive exercise differentially impacts the right ventricle (RV) versus left ventricle (LV), yet the underlying hemodynamic basis remains unclear. Using pressure-volume analyses and pressure-telemetry implantation in mice, we confirmed a marked disproportionate and persistent negative impact of exhaustive exercise on the RV. These differences in responses of the ventricles to exhaustive exercise are of clinical relevance, reflecting ∼2-fold greater hemodynamic RV loads versus LVs arising from massive (∼45 mmHg) increases in LV end-diastolic pressures at exhaustion.

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Sankova, Barbora, Jakub Machalek, and David Sedmera. "Effects of mechanical loading on early conduction system differentiation in the chick." American Journal of Physiology-Heart and Circulatory Physiology 298, no. 5 (May 2010): H1571—H1576. http://dx.doi.org/10.1152/ajpheart.00721.2009.

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The primary ring, a horseshoe-shaped structure situated between the left and right ventricle and connected superiorly to the atrioventricular canal, is the first specialized fast ventricular conduction pathway in the embryonic heart. It has been first defined immunohistochemically and is characterized as a region of slow myocyte proliferation. Recent studies have shown that it participates in spreading the ventricular electrical activation during stages preceding ventricular septation in the mouse, chick, and rat. Here we demonstrate its presence using optical mapping in chicks between embryonic days (ED) 3–5. We then tested the effects of hemodynamic unloading in the organ culture system upon its functionality. In ED3 hearts cultured without hemodynamic loading for 24 h, we observed a significant decrease in the percentage activated through the primary ring conduction pathway. A morphological examination revealed arrested growth, collapse, and elongation of the outflow tract and disorganized trabeculation. A similar reversal toward more primitive activation patterns was observed with culture between ED4 and ED5. This phenotype was completely rescued with the artificial loading of the ventricles with a droplet of silicone oil. We conclude that an appropriate loading is required during the early phases of the conduction system formation and maturation.

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Shimamoto, Yoriko, Hiroyuki Shimamoto, and Hideo Nakamura. "Hemodynamic changes during dietary salt loading in elderly patients with essential hypertension." Nippon Ronen Igakkai Zasshi. Japanese Journal of Geriatrics 27, no. 3 (1990): 332–42. http://dx.doi.org/10.3143/geriatrics.27.332.

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Konrady, A. O., I. V. Emelyanov, E. V. Frolova, A. Y. Bagrov, and E. V. Shlyakhto. "534 HEMODYNAMIC CHANGES DURING ACUTE SALT LOADING IN PATIENTS WITH RESISTANT HYPERTENSION." Journal of Hypertension 30 (September 2012): e157. http://dx.doi.org/10.1097/01.hjh.0000420809.97784.d1.

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Jammar, Prakash, Deba Gopal Pathak, Ismatara Begum, and Ram Chandraji Chauhan. "A clinical comparative study of two intubating doses of cis-atracurium during general anaesthesia for gynaecological surgery." International Journal of Basic & Clinical Pharmacology 6, no. 5 (April 24, 2017): 1206. http://dx.doi.org/10.18203/2319-2003.ijbcp20171677.

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Background: Cisatracurium is one of the cis-cis isomer of atracurium (51W89:1R-cis 1’R-cis atracurium) an intermediate duration non-depolarising neuromuscular blocking drug and is devoid of histamine release. However, 2× ED95 dose of cisatracurium does not provide satisfactory intubating condition. The recommended intubating dose of cisatracurium is 3 ×ED95. The objective of this study was to evaluate and compare duration of action, hemodynamic effects and any adverse effects for different doses of cisatracurium.Methods: After Institutional Ethical Committee approval and informed patient consent, 80 patients of ASA I and II in the age group of 20-60 years were selected and included in the study. Patients were divided in two groups of 40 each, group A received intravenously 3×ED95 (0.15 mg/kg) loading dose of cisatracurium and group B received intravenously 4×ED95 (0.2 mg/kg) loading dose of cisatracurium.Results: After induction, MAP and HR shows decrease in both groups but neither statistically nor clinically significant. Better hemodynamic stability and longer duration of action was found in group B compared to group A. No adverse effects noted in both groups.Conclusions: 4×ED95 dose of cisatracurium provides longer duration of action and more stable hemodynamic status than 3×ED95. No associated signs of histamine release were detected clinically.

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Pandey, Pawan Kumar, Chandan Paul, Malay K. Das, and Krishnamurthy Muralidhar. "Assessment and visualization of hemodynamic loading in aneurysm sac and neck: Effect of foam insertion." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 235, no. 8 (May 10, 2021): 927–39. http://dx.doi.org/10.1177/09544119211015569.

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Shape memory polymer (SMP) foam is often proposed as the future alternative of coils in aneurysm treatment devices. Present work numerically investigates the unsteady, three-dimensional simulation of blood flow in a cerebral aneurysm filled with SMP foam. Simulations are conducted on patient-specific geometries with realistic blood velocity waveform imposed at the inlet while SMP foam is treated as a porous medium. The present study introduces a “loading risk map” that helps to visualize the hemodynamic effect of foam insertion on the aneurysm sac and neck. The loading risk maps suggest that while the SMP foam subdues the flow and wall shear pulsations in the aneurysm sac, the pressure distribution is minimally affected. The maps suggest that while the downstream lip is the most risk-prone site for both geometries, downstream vascular anatomy significantly influences foam efficiency in reducing pressure and wall shear stress loading.

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Olgiati, R., G. Atchou, and P. Cerretelli. "Hemodynamic effects of resistive breathing." Journal of Applied Physiology 60, no. 3 (March 1, 1986): 846–53. http://dx.doi.org/10.1152/jappl.1986.60.3.846.

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To examine the acute hemodynamic effects induced by large swings in intrathoracic pressure such as may be generated by obstructive lung disease, airway obstruction was simulated by means of two different fixed external alinear resistances and the results were compared with those for unobstructed breathing (C). Eight normal subjects breathed through external resistances during inspiration (I), expiration (E), or both (IE) at rest (Re) and exercise (Ex). The resistances were chosen to induce similar mouth pressure (Pm) swings at Re and Ex. Pleural pressures (Ppl) were found to correlate closely with Pm. During IE resistive breathing mean swings in Pm were -31 and +19 cmH2O at Re and -38 and +22 cmH2O at Ex, with a corresponding decrease in minute ventilation (-30 and -18%) and an increase in end-tidal PCO2 (+5.6 and +4.2 Torr); these were associated with an increase in heart rate (delta HR = 4 and 6 beats/min) and systolic systemic arterial pressure (delta Psas = 10 and 14 Torr at Re and Ex, respectively). O2 consumption and cardiac output did not change. The myocardial O2 consumption, estimated from the product HR X (Psas--Ppl), increased by 17 and 20% at Re and Ex, respectively. Changes in mechanics, gas exchange, and hemodynamics were less pronounced during I or E resistive loading. It is concluded that breathing through a tight external resistance during IE at Re and Ex increases the metabolic load on the myocardium.

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Legault, Louis, Paul van Nguyen, Donna L. Holliwell, and Frans H. H. Leenen. "Hemodynamic and plasma atrial natriuretic factor responses to cardiac volume loading in young versus older normotensive humans." Canadian Journal of Physiology and Pharmacology 70, no. 12 (December 1, 1992): 1549–54. http://dx.doi.org/10.1139/y92-222.

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To assess the effects of age on responsiveness of atrial natriuretic factor (ANF) release, and the possible contribution of cardiac sympathetic activity, in young (n = 8) and older normotensives (n = 7), the effects of cardiac volume load on plasma ANF, central venous pressure, and general hemodynamics were evaluated. Studies were performed after pretreatment with placebo or 80 mg propranolol. Cardiac volume loading increased central venous pressure by 3–5 mmHg (1 mmHg = 133.3 Pa); β-blockade did not affect this response. Cardiac volume load caused significant increases in heart rate (10–15 beats/min) and cardiac index (by 0.7–0.8 L∙min−1∙m−2) and decreases in plasma catecholamines. Propranolol attenuated the increases in heart rate and cardiac index. These hemodynamic responses did not differ significantly between the two groups of subjects. Cardiac volume load significantly increased plasma ANF, by 87 ± 21 pg/mL in the young normotensives and by 212 ± 33 pg/mL in the older normotensives (p < 0.01, young vs. older). β-Blockade did not affect this different response. Our results show that the plasma ANF response to volume loading is potentiated by aging. Although differences in atrial stretch cannot be excluded, this effect may relate to the decrease in clearance of plasma ANF occurring with aging.Key words: cardiac volume load, atrial natriuretic factor, aging, β-blockade.

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Matavelli, Luis C., Xiaoyan Zhou, Jasmina Varagic, Dinko Susic, and Edward D. Frohlich. "Salt loading produces severe renal hemodynamic dysfunction independent of arterial pressure in spontaneously hypertensive rats." American Journal of Physiology-Heart and Circulatory Physiology 292, no. 2 (February 2007): H814—H819. http://dx.doi.org/10.1152/ajpheart.00671.2006.

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We have previously shown that salt excess has adverse cardiac effects in spontaneously hypertensive rats (SHR), independent of its increased arterial pressure; however, the renal effects have not been reported. In the present study we evaluated the role of three levels of salt loading in SHR on renal function, systemic and renal hemodynamics, and glomerular dynamics. At 8 wk of age, rats were given a 4% ( n = 11), 6% ( n = 9), or 8% ( n = 11) salt-load diet for the ensuing 8 wk; control rats ( n = 11) received standard chow (0.6% NaCl). Rats had weekly 24-h proteinuria and albuminuria quantified. At the end of salt loading, all rats had systemic and renal hemodynamics measured; glomerular dynamics were specially studied by renal micropuncture in the control, 4% and 6% salt-loaded rats. Proteinuria and albuminuria progressively increased by the second week of salt loading in the 6% and 8% salt-loaded rats. Mean arterial pressure increased minimally, and glomerular filtration rate decreased in all salt-loaded rats. The 6% and 8% salt-loaded rats demonstrated decreased renal plasma flow and increased renal vascular resistance and serum creatinine concentration. Furthermore, 4% and 6% salt-loaded rats had diminished single-nephron plasma flow and increased afferent and efferent arteriolar resistances; glomerular hydrostatic pressure also increased in the 6% salt-loaded rats. In conclusion, dietary salt loading as low as 4% dramatically deteriorated renal function, renal hemodynamics, and glomerular dynamics in SHR independent of a minimal further increase in arterial pressure. These findings support the concept of a strong independent causal relationship between salt excess and cardiovascular and renal injury.

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Farooq, Sajid, Muhammad Farhan Ali Rizvi, Sana Urooj Hashmi, Mirza Ahmad Raza Baig, Hafiz Syed Muhammad Irfan Yousaf, and Tasadduq Munir. "A prospective randomized study to see the effects of combined administration of dexmedetomidine plus propofol versus propofol alone in cardiac surgical patients." Professional Medical Journal 28, no. 04 (April 10, 2021): 447–54. http://dx.doi.org/10.29309/tpmj/2021.28.04.5815.

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Objective: To compare the hemodynamics changes, intraoperative awareness and postoperative delirium after combined administration of dexmedetomidine plus propofol versus propofol alone in cardiac surgical patients. Study Design: Randomized Clinical Trial. Setting: Cardiac Center, Bahawal Victoria Hospital, Bahawalpur. Period: 1st December 2018 to January 2020. Material & Methods: Sixty-two (62) patients who underwent different cardiac surgical procedures were included in the study. Patients were randomly divided in group 1 {Dexmedetomidine (DEX) +Propofol} and group 2 {propofol alone}. Induction in group 1 was done by loading dose of DEX (0.7 microgram/kg) while induction in group 2 was done by Lignocaine 1.5 mg/kg. Heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and mean arterial pressure (MAP) were recorded at different time intervals. Intraoperative awareness and post-operative delirium was also assessed. Results: All hemodynamic parameters (HR, SAP, DAP, MAP) were statistically significant lower in group 1 in comparison to group 2 at different intervals indicating a more stable hemodynamic profile in group 1. End tidal CO2, pH, and peak airway pressures were not statistically significant between both groups. Intra-operative awareness was diagnosed in 1 (3.2%) patients in group 1 and in 5 (16.1%) patients in group 2 (p-value 0.08). Delirium was diagnosed in 3 (9.6%) patients in group 1 and in only 1 (3.2%) patients in group 2 (p-value 0.30). Conclusion: Combined administration of DEX and propofol produces more stable hemodynamics, less intraoperative awareness but more incidence of delirium as compared to propofol alone in cardiac surgical patients.

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Manifield, James, Nikolaos Chynkiamis, Charikleia Alexiou, Dimitrios Megaritis, Emily Hume, Gill Barry, and Ioannis Vogiatzis. "Acute thoracoabdominal and hemodynamic responses to tapered flow resistive loading in healthy adults." Respiratory Physiology & Neurobiology 286 (April 2021): 103617. http://dx.doi.org/10.1016/j.resp.2021.103617.

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SHIMAMOTO, HIROYUKI, MITSUNORI OKAMOTO, YUJI YOKOTE, EIICHIRO SAKURA, TETSUYA OSHIMA, KOJI MATSUMOTO, YUKIKO TSUCHIOKA, HIDEO MATSUURA, TOKUO TSUBOKURA, and GORO KAJIYAMA. "Hemodynamic response to dietary sodium loading in essential hypertension studied with Doppler echocardiography." Japanese Circulation Journal 55, no. 1 (1991): 5–14. http://dx.doi.org/10.1253/jcj.55.5.

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Hoog, Tanner G., Samantha J. Fredrickson, Chih-Wei Hsu, Steven M. Senger, Mary E. Dickinson, and Ryan S. Udan. "The effects of reduced hemodynamic loading on morphogenesis of the mouse embryonic heart." Developmental Biology 442, no. 1 (October 2018): 127–37. http://dx.doi.org/10.1016/j.ydbio.2018.07.007.

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Williamson, Megan L., Matthew D. Muller, Edward J. Ryan, Chul-Ho Kim, Robert P. Blankfield, and Ellen L. Glickman. "The Effects of Acute Salt Loading on Hemodynamic Parameters in Young Caucasian Males." Medicine & Science in Sports & Exercise 42 (May 2010): 126. http://dx.doi.org/10.1249/01.mss.0000386293.73301.04.

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Bailey, James M., Bruce E. Miller, Wei Lu, Steven R. Tosone, Kirk R. Kanter, and Vincent K. H. Tam. "The Pharmacokinetics of Milrinone in Pediatric Patients after Cardiac Surgery." Anesthesiology 90, no. 4 (April 1, 1999): 1012–18. http://dx.doi.org/10.1097/00000542-199904000-00014.

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Background Milrinone has been shown to increase cardiac output in children after cardiac surgery, but pharmacokinetic analysis has not been used to identify effective dose regimens. The purpose of this study was to characterize the pharmacokinetics of milrinone in infants and children and to apply the results to the issue of dosing. Methods Twenty children were studied after they underwent repair of congenital cardiac defects. Control hemodynamic measurement was made after the children were separated from cardiopulmonary bypass, and each patient was given a loading dose of 50 microg/kg progressively in 5 min. Hemodynamic measurements were recorded again at the end of the loading dose and when a blood sample was taken to determine milrinone plasma concentrations. Further blood samples were taken during the next 16 h for milrinone plasma concentration analysis. The pharmacokinetics of milrinone were analyzed using the population pharmacokinetic program NONMEM. Results The loading dose of milrinone resulted in a mean decrease in mean blood pressure of 12% and a mean increase in cardiac index of 18% at a mean peak plasma concentration of 235 ng/ml. The pharmacokinetics of milrinone were best described by a three-compartment model. In the optimal model, all volumes and distribution clearances were proportional to weight, and weight-normalized elimination clearance was proportional to age; ie., Cl1 = 2.5 x weight x (1 + 0.058 x age) where Cl1 is expressed as ml/min, and the units of weight and age are kg and months, respectively. Conclusions A loading dose of 50 microg/kg effectively increases cardiac index in children after cardiac surgery. Simulations indicate that the peak plasma concentration can be maintained by following the loading dose of 50 microg/kg with an infusion of approximately 3 microg x kg(-1) x min(-1) for 30 min and then a maintenance infusion, which may require adjustment for age.

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Okamoto, Keiko, Chihiro Tanikawa, and Kenji Takada. "Hemodynamic Changes in the Masseter and Superior Orbicularis Oris Muscles before and after Exercise Load: A Comparison between Young Adult Women and Middle-Aged to Old Adult Women." International Journal of Dentistry 2022 (August 27, 2022): 1–9. http://dx.doi.org/10.1155/2022/5340301.

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Background. The vascularity index (VI) is useful for measuring the hemodynamics on ultrasound imaging. However, there are no reports concerning the application of the VI to facial muscles. Objective. The aim of this study was (1) to establish a method of measuring the hemodynamics in facial muscles in a constant way and (2) to evaluate the hemodynamic changes in the masseter and superior orbicularis oris muscles (SOOMs) before and after exercise load in two subject groups of females of different ages. Methods. (1) The VI in the SOOM was calculated, and the test-retest reliability was assessed in seven healthy adults. (2) The VIs in the left-side masseter and SOOM were calculated in 3 sessions: before exercise loading (T0), immediately after loading (T1), and 5 minutes after T1 (T2) for the young adult group (YAG, n = 20; age range, 20–35 years) and the middle-aged to old group (MOG, n = 20; age range, 50–70 years). Tasks were gum chewing for the masseter muscle and lip sealing for the SOOM. The differences in the mean peak flows between two sessions were examined. Results. (1) Significant differences were not noted for the repeatedly measured average volumes of blood flow with good test-retest agreement (intraclass correlation coefficient = 0.81). (2) In both muscles of the YAG, there were a significant increase in T1 compared with T0 and a significant decrease in T2 compared with T1 (all p < 0.05 ). In both muscles of the MOG, no significant differences were noted in either comparison. Conclusions. A method of measuring the hemodynamics in facial muscles was developed and showed good reliability. Changes in the blood flow after exercise load in these muscles may vary with age in women.

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Lee, Soo Kyung, Mi Ae Jeong, Jeong Min Sung, Hyo Jin Yeon, Ji Hee Chang, and Hyunyoung Lim. "Effect of remifentanil infusion on the hemodynamic response during induction of anesthesia in hypertensive and normotensive patients: a prospective observational study." Journal of International Medical Research 47, no. 12 (November 4, 2019): 6254–67. http://dx.doi.org/10.1177/0300060519883568.

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Background The induction of general anesthesia may cause hemodynamic instability. Remifentanil is often administered to suppress the hemodynamic response. We aimed to evaluate the effect of remifentanil infusion on the hemodynamic response to induction of anesthesia in hypertensive and normotensive patients. Methods Patients were divided into two groups: Group H (n = 102) were hypertensive patients and Group C (n = 107) were normotensive patients. During induction, all patients received 1 µg/kg of remifentanil as a loading dose over 2 minutes, followed by a continuous infusion at 0.05 µg/kg/minute. We analyzed the systolic, diastolic, and mean pressures and heart rate pre-induction, pre-intubation, immediately post-intubation, and at 2, 4, 6, 8, and 10 minutes after intubation. Results The systolic, diastolic, and mean pressures before induction were significantly higher in group H compared with group C, but there was no significant difference between the two groups immediately after intubation. Blood pressures immediately after intubation were similar to the pre-induction blood pressure. There was no significant difference in heart rate between the two groups at any time point. Conclusions Remifentanil infusion effectively attenuates the hemodynamic response to induction of general anesthesia in hypertensive and normotensive patients.

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Uretsky, B. F., J. G. Verbalis, T. Generalovich, A. Valdes, and P. S. Reddy. "Plasma vasopressin response to osmotic and hemodynamic stimuli in heart failure." American Journal of Physiology-Heart and Circulatory Physiology 248, no. 3 (March 1, 1985): H396—H402. http://dx.doi.org/10.1152/ajpheart.1985.248.3.h396.

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Arginine vasopressin (AVP) regulation was studied in 42 patients with severe heart failure (CHF) and 10 patients without CHF during cardiac catheterization. Plasma AVP levels were elevated in CHF compared with non-CHF patients (2.98 +/- 2.48 vs. 1.01 +/- 0.44 pg/ml, P less than 0.01). In non-CHF patients, osmotic loading with angiographic contrast caused increases in plasma osmolality (283 +/- 4 to 290 +/- 5 mosmol/l, P less than 0.05) and AVP (1.01 +/- 0.44 to 1.79 +/- 0.20 pg/ml, P less than 0.001). In 10 CHF patients, similar osmotic loading produced an increase in plasma osmolality (275 +/- 13 to 288 +/- 17 mosmol/l, P less than 0.05) and an exaggerated rise in plasma AVP (3.61 +/- 3.17 to 16.30 +/- 12.17 pg/ml, P less than 0.001). The increase in plasma AVP per unit increase in osmolality was greater (P less than 0.01) in the CHF patients (1.36 +/- 1.25 pg . mosmol-1 . 1(-1)) than in non-CHF patients (0.18 +/- 0.17). To determine whether improved cardiac performance would lower AVP levels, 18 CHF patients received the experimental agent MDL 17,043, with improved cardiac index (1.9 +/- 0.4 to 3.3 +/- 0.7 1 . min-1 . m-2, P less than 0.001). Plasma AVP levels did not change significantly (1.99 +/- 0.74 to 2.81 +/- 2.06 pg/ml), but significant inverse correlations were found between changes in plasma AVP and changes in mean (r = -0.53) and systolic (r = -0.65) arterial pressure after MDL 17,043 infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

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Freeman, G. L., S. D. Prabhu, L. E. Widman, and J. T. Colston. "An analysis of variability of left ventricular pressure decay." American Journal of Physiology-Heart and Circulatory Physiology 264, no. 1 (January 1, 1993): H262—H268. http://dx.doi.org/10.1152/ajpheart.1993.264.1.h262.

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This study evaluated whether the time course of left ventricular (LV) pressure decay is consistent from beat to beat in the normal heart under tightly controlled experimental conditions. We determined the variability of LV isovolumic relaxation and compared it with that of other hemodynamic parameters. Pressure decay was evaluated using a monoexponential time constant (T), a half-time (T1/2), and an average rate (Ravg) in nine chronically instrumented dogs. To eliminate physical factors that could lead to variability, the dogs were studied at paced heart rates after autonomic blockade and during apnea. At a heart rate of 160 beats/min the coefficient of variation (SD/mean, expressed as a percent) was higher for T (4.7%, P < 0.005), T1/2 (5.0%, P < 0.005), and Ravg (3.2%, P < 0.005) than for dP/dtmax (1.9%), as well as for end-diastolic volume (1.2%), end-systolic volume (1.2%), or end-systolic pressure (1.8%). Similar differences were present at 200 beats/min. Pressure decay was also assessed during major loading shifts induced by rapid caval occlusion. Surprisingly, comparison of first and last beats did not show significant differences for T or T1/2 but did for all standard hemodynamic parameters and for Ravg. While the best correlation with a relaxation parameter and hemodynamic parameters during changing loading conditions was for Ravg, the correlations were not consistent in every case. We conclude that LV pressure decay shows marked variability, unrelated to the algorithm used to assess it. Ravg, a model independent parameter, may be a useful way to quantify LV pressure fall.

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Chin, Young Jhoon, In Hak Kim, Chan Jong Chung, and Seung Cheol Lee. "Hemodynamic Changes and Transesopahgeal Echocardiographic Findings of Intravenous Amiodarone Loading in Patients Undergoing CABG." Korean Journal of Anesthesiology 48, no. 4 (2005): 375. http://dx.doi.org/10.4097/kjae.2005.48.4.375.

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Macnab, Andrew J., Mark Levine, Ned Glick, John Macready, Mary Elliott, and David F. Wensley. "MIDAZOLAM FOLLOWING OPEN HEART SURGERY IN CHILDREN: HEMODYNAMIC EFFECT OF A LOADING DOSE. 290." Pediatric Research 39 (April 1996): 51. http://dx.doi.org/10.1203/00006450-199604001-00309.

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Bondareva, S. V., R. A. Vartbaronov, K. V. Ponomarenko, K. G. Bagaudinov, M. N. Khomenko, and N. N. Uglova. "Resistance and hemodynamic reactions in healthy pilots under the conditions of passive orthostatic loading." Human Physiology 38, no. 7 (December 2012): 745–50. http://dx.doi.org/10.1134/s0362119712070055.

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Friesen, Robert H., Christopher S. Nichols, Mark D. Twite, Kathryn A. Cardwell, Zhaoxing Pan, Biagio Pietra, Shelley D. Miyamoto, Scott R. Auerbach, Jeffrey R. Darst, and D. Dunbar Ivy. "The Hemodynamic Response to Dexmedetomidine Loading Dose in Children With and Without Pulmonary Hypertension." Survey of Anesthesiology 58, no. 3 (June 2014): 129–30. http://dx.doi.org/10.1097/01.sa.0000446239.71400.19.

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van Loosdregt, Inge A. E. W., Giulia Argento, Anita Driessen-Mol, Cees W. J. Oomens, and Frank P. T. Baaijens. "Cell-mediated retraction versus hemodynamic loading – A delicate balance in tissue-engineered heart valves." Journal of Biomechanics 47, no. 9 (June 2014): 2064–69. http://dx.doi.org/10.1016/j.jbiomech.2013.10.049.

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Brouhard, Ben H. "Renal hemodynamic changes in humans: response to protein loading in normal and diseased kidneys." American Journal of Medicine 82, no. 4 (April 1987): 868. http://dx.doi.org/10.1016/0002-9343(87)90049-0.

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Journal articles on the topic 'Hemodynamic loading'

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