Effects of ischemic pre-conditioning on electrically stimulated contractions.

PURPOSE: Ischemic pre-conditioning (IPC) offers protection against future ischemic events and may improve sports performance due to several mechanisms at local and systemic levels. This study investigates the local effects on muscle contractility in electrically induced muscle contractions, thus effectively excluding any uncontrolled change in the motor drive. METHODS: Twenty-one subjects were divided into two groups: 12 subjects in the IPC group (3 × 5/5 min right arm ischemia/reperfusion; cuff pressure 250 mmHg) and 9 subjects in the SHAM group (same treatment at 20 mmHg). The adductor pollicis was contracted by supramaximal stimulation of the ulnar nerve with single pulses, trains of stimuli (5, 8, 10 and 12 Hz, 1-s duration) and bursts (4 pulses, 25 Hz), all separated by 5-s intervals. The stimulation sequence was delivered before and 15 and 30 min after IPC/SHAM treatment. The isometric contraction force, the superficial electromyographic signal, and tissue oxygenation were continuously monitored. RESULTS: A significant force decrease in time was observed at 8, 10 (p < 0.01) and 12 Hz (p < 0.05) along with a decrease in half-relaxation time in single twitches and bursts (p = 0.01), regardless of treatment. This general time-related weakening was more marked in IPC than SHAM at 5-Hz stimulation. No effects were observed on the magnitude of the superficial electromyographic signal. CONCLUSION: Data indicate that IPC does not increase muscle force during electrically stimulated contractions, supporting the idea that IPC's ergogenic effects are not due to increased muscle contractility.

Effects of Using Virtual Reality Technology on Pain and Hemodynamic Variables in Patients Receiving Hand Laceration Repair in an Emergency Department: A Randomized Controlled Trial.

BACKGROUND: Pain and altered hemodynamic variables are among the most common complications in patients undergoing hand laceration repair in an Emergency Department. AIM: This study aimed to evaluate the effects of using virtual reality (VR) technology on pain and hemodynamic variables in patients receiving hand laceration repair in an Emergency Department. METHOD: This nonblinded randomized clinical trial included 160 patients undergoing laceration repair to their hands under local anesthetics from November 2020 to May 2021. The participants were randomly allocated to the experimental and control groups. Patients in the control group received routine care (such as ambient noise reduction, providing explanations about the surgery, and Lidocaine injection before the surgery). In the experimental group, a video containing natural landscapes and sounds was played using a semi-immersive VR headset during the surgery. Pain level and hemodynamic variables were measured immediately before and after the intervention. The pain was measured using the Critical Care Pain Observation Tool and Visual Analog Scale. RESULTS: Immediately after the intervention, systolic blood pressure (BP), respiration rate, and pain intensity were significantly lower in the intervention group compared with the control group (p < .05). There were no significant differences between the intervention and control groups regarding diastolic BP, mean BP, SPO2, heart rate, and muscular tension (p > .05). CONCLUSIONS: Semi-immersive VR is effective in managing pain and hemodynamic variables during hand laceration repair. The nurses could use the semi-immersive VR to better control of pain and hemodynamic variables during hand laceration repair.

The prognostic role of advanced hemodynamic variables in patients with left ventricular assist devices.

BACKGROUND: Invasive hemodynamic variables obtained from right heart catheterization have been used for risk-stratifying patients with advanced heart failure (HF). However, there is a paucity of data on the prognostic value of invasive hemodynamic variables in patients with left ventricular assist devices (LVAD). We hypothesized that cardiac power output (CPO), cardiac power efficiency (CPE), and left ventricular stroke work index (LVSWI) can serve as prognostic markers in patients with LVADs. METHODS: Baseline hemodynamic data from patients who had LVAD ramp studies at our institution from 4/2014 to 7/2018 were prospectively collected, from which advanced hemodynamic variables (CPO, CPE, and LVSWI) were retrospectively analyzed. Univariate and multivariable analyses were performed for hemocompatibility-related adverse events (HRAE), HF admissions, and mortality. RESULTS: Ninety-one participants (age 61 ± 11 years, 34% women, 40% Black or African American, and 38% ischemic cardiomyopathy) were analyzed. Low CPE was significantly associated with mortality (HR 2.42, 95% CI 1.02-5.74, p = 0.045) in univariate analysis and Kaplan-Meier analysis (p = 0.04). Low LVSWI was significantly associated with mortality (HR 2.13, 95% CI 1.09-4.17, p = 0.03) in univariate analysis and Kaplan-Meier analysis (p = 0.02). CPO was not associated with mortality. CPO, CPE, and LVSWI were not associated with HRAE or HF admissions. CONCLUSIONS: Advanced hemodynamic variables can serve as prognostic indicators for patients with LVADs. Low CPE and LVSWI are prognostic for higher mortality, but no variables were associated with HF admissions or HRAEs.

The Effect of Hand Massage on Preoperative Anxiety Level and Hemodynamic Variables in Children: A Randomized Controlled Trial.

PURPOSE: The study was conducted to determine the effect of hand massage applied to preoperative children on anxiety level and hemodynamic variables. DESIGN: This research study is a randomized controlled trial with control and study groups, pre- and post-tests. METHODS: This study was conducted between April and September 2017 with 84 children who were planned to receive an operation by applying general/local anesthesia in a province in the south of Turkey. The population of the research was composed of children between the ages 9 and 12 (study group = 42 and control group = 42). The data were collected through "Child and Parent Information Form," "State-Trait Anxiety Inventory for Children," "Physical Symptoms Follow-up Form for Anxiety," and "Satisfaction Evaluation Scale." FINDINGS: The state-trait anxiety mean after hand massage was found to be 25.78 ± 5.90 in the study group, and 31.80 ± 6.51 in the control group (P < .05). There was a statistically significant difference (P < .05) between the systolic blood pressures and heart rate averages of the children in the study group after hand massage. There was a negative correlation between the satisfaction hand massage and state-trait anxiety means of the study group children (P < .05). CONCLUSIONS: Hand massage was found to have a positive effect on reducing anxiety, systolic blood pressure and heart rate. No effect was found on diastolic blood pressure, respiratory rate and SpO2. We recommend that more extensive studies on hand massage are performed.

Non-Newtonian Blood Modeling in Intracranial Aneurysm Hemodynamics: Impact on the Wall Shear Stress and Oscillatory Shear Index Metrics for Ruptured and Unruptured Cases.

When simulating blood flow in intracranial aneurysms (IAs), the Newtonian model seems to be ubiquitous. However, analyzing the results from the few studies on this subject, the doubt remains on whether it is necessary to use non-Newtonian models in computational fluid dynamics (CFD) simulations of cerebral vascular flows. The objective of this study is to investigate whether different rheology models would influence the hemodynamic parameters related to the wall shear stress (WSS) for ruptured and unruptured IA cases, especially because ruptured aneurysms normally have morphological features, such as lobular regions and blebs, that could trigger non-Newtonian phenomena in the blood flow due to low shear rates. Using CFD in an open-source framework, we simulated four ruptured and four unruptured patient-specific aneurysms to assess the influence of the blood modeling on the main hemodynamic variables associated with aneurysm formation, growth, and rupture. Results for WSS and oscillatory shear index (OSI) and their metrics were obtained using Casson and Carreau-Yasuda non-Newtonian models and were compared with those obtained using the Newtonian model. We found that all differences between non-Newtonian and the Newtonian models were consistent among all cases irrespective of their rupture status. We further found that the WSS at peak systole is overestimated by more than 50% by using the non-Newtonian models, but its metrics based on time and surface averaged values are less affected-the maximum relative difference among the cases is 7% for the Casson model. On the other hand, the surface-averaged OSI is underestimated by more than 30% by the non-Newtonian models. These results suggest that it is recommended to investigate different blood rheology models in IAs simulations when specific parameters to characterize the flow are needed, such as peak-systole WSS and OSI.

Volume-associated hemodynamic variables for prediction of cardiac surgery-associated acute kidney injury.

BACKGROUND: Delayed diagnosis of acute kidney injury (AKI) is common because the changes in renal function markers often lag injury. We aimed to find optimal non-invasive hemodynamic variables for the prediction of postoperative AKI and AKI renal replacement therapy (RRT). METHODS: The data were collected from 1,180 patients who underwent cardiac surgery in our hospital between March 2015 and Feb 2016. Postoperative central venous pressure (CVP), mean arterial pressure (MAP), heart rate, PaO2, and PaCO2 on ICU admission and daily fluid input and output (calculated as 24 h PFO) were monitored and compared between AKI vs. non-AKI and RRT vs non-RRT cases. RESULTS: The AKI and AKI-RRT incidences were 36.7% (n = 433) and 1.2% (n = 14). Low cardiac output syndromes (LCOSs) occurred significantly more in AKI and RRT than in non-AKI or non-RRT groups (13.2% vs. 3.9%, P < 0.01; 42.9% vs. 7.1%, P < 0.01). CVP on ICU admission was significantly higher in AKI and RRT than in non-AKI and non-RRT groups (11.5 vs. 9.0 mmHg, P < 0.01; 13.3 vs. 9.9 mmHg, P < 0.01). 24 h PFO in AKI and RRT cases were significantly higher than in non-AKI or non-RRT patients (1.6% vs. 0.9%, P < 0.01; 3.9% vs. 0.8%, P < 0.01). The areas under the ROC curves to predict postoperative AKI by CVP on ICU admission (> 11 mmHg) + LCOS + 24 h PFO (> 5%) and to predict AKI-RRT by CVP on ICU admission (> 13 mmHg) + LCOS + 24 h PFO (> 5%) were 0.763 and 0.886, respectively. CONCLUSION: The volume-associated hemodynamic variables, including CVP on ICU admission, LCOS, and 24 h PFO after surgery could predict postoperative AKI and AKI-RRT.

Comparing the effect of dexmedetomidine and labetalol on hemodynamic variables in patients undergoing microlaryngoscopy.

INTRODUCTION: This study was conducted to compare the effect of dexmedetomidine and labetalol on hemodynamic variables in patients undergoing microlaryngoscopy. MATERIAL AND METHODS: In this randomized clinical trial study 70 patients undergoing microlaryngoscopy were involved. The patients were randomly assigned into two groups. Patients in dexmedetomidine group received 0.5 µg/kg of dexmedetomidine diluted in 100 ml of saline solution and the patients in the second group received 0.25 mg/kg of labetalol before anesthesia induction. At the beginning of the surgery, dexmedetomidine was infused at the dose of 0.4 µg/kg/h in the dexmedetomidine group, and labetalol at the dose of 1.8 mg/kg/h in the labetalol group. Patients' systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate at different times and anesthesia and surgery duration, recovery time and dose of prescribed propofol were recorded and compared between two groups. RESULTS: There was a significant difference in mean systolic blood pressure, mean diastolic blood pressure, mean arterial blood pressure and mean heart rate between two groups at different times (p value < 0.05). CONCLUSION: The results of this study indicated that dexmedetomidine had higher efficacy, compared to labetalol, in reducing diastolic blood pressure, systolic blood pressure, heart rate, and mean arterial blood pressure following microlaryngoscopy.

Hemodynamic changes caused by acupuncture in healthy volunteers: a prospective, single-arm exploratory clinical study.

BACKGROUND: Radial pressure pulse wave (RPPW) examination has been a key diagnostic component of traditional Chinese medicine. The objective of this study was to investigate the changes in RPPW along with various hemodynamic variables after acupuncture stimulation and to examine the validity of pulse diagnosis as a modern diagnostic tool. METHODS: We conducted acupuncture stimulation at both ST36 acupuncture points in 25 healthy volunteers. We simultaneously assessed the RPPW by pulse tonometry; heart rate variability (HRV) by electrocardiogram; photoplethysmogram (PPG) signals, respiration rate, peripheral blood flow velocity and arterial depth by ultrasonography; and cardiac output by impedance cardiography, before, during and after a session of acupuncture stimulation. RESULTS: We observed consistent patterns of increased spectral energy at low frequency (<10 Hz) and pulse power using RPPW examination and in the amplitude and systolic area of the PPG signal during the entire acupuncture session. The low- and high-frequency domains of HRV increased and decreased, respectively, during the acupuncture session. The peripheral blood velocity rose shortly after needle insertion, reached a maximum in the middle of the session and decreased afterwards. The augmentation index (AIX) and pulse transit time (PTT) obtained from RPPW did not change significantly. CONCLUSION: Acupuncture stimulation at ST36 in healthy subjects increased the peripheral pulse amplitudes (pressure pulse wave (PPW) and PPG), blood flow velocity (ultrasonography) and sympathetic nerve activity (HRV). The lack of changes in the AIX and PTT suggests that the increased pulse amplitudes and blood flow velocity may result from increased cardiac output. TRIAL REGISTRATION: Clinical Research Information Service ( KCT0001663 ).

Which hemodynamic parameter predicts nitroglycerin-potentiated head-up tilt test response?

BACKGROUND: The aim of our study was to identify the early hemodynamic predictors of head-up tilt test (HUTT) outcome in healthy patients with recurrent unexplained syncope. METHODS AND RESULTS: The study involved 95 patients (mean age 38 ± 15; 42 male) who were referred for the evaluation of the syncopal episodes from October 2012 to May 2013. According to the nitroglycerin-potentiated diagnostic tilt test response, the study population was divided into two groups: HUTT+ Group (61 patients, mean age 37 ± 10; 27 male) and HUTT- Group (34 patients, mean age 38 ± 11; 15 male) with no tilt-induced syncope. Finger arterial blood pressure (BP) was recorded during tilt testing. Left ventricular stroke volume (SV), cardiac output (CO), and total peripheral resistance (TPR) were computed from the pressure pulsations. After nitroglycerin administration, the HUTT+ Group showed a significant increase in heart rate (92.0 ± 7.3 beats/min vs 68.9 ± 8.7 beats/min, P < 0.0001), with well-maintained systolic BP (111.6 ± 14.1 mm Hg vs 108.8 ± 11.5 mm Hg; P = 0.332) and diastolic BP (66.1 ± 8.5 mm Hg vs 63.1 ± 6.9 mm Hg; P = 0.0913); a significant decrease in SV (53.9 ± 8.0 mL vs 78.6 ± 8.2 mL; P < 0.0001) and CO (4.0 ± 0.5 L/min vs 5.8 ± 1.0 L/min; P < 0.001), and a significant increase in TPR (1.3 ± 0.3 U vs 0.9 ± 0.2 U, P < 0.0011). We tested three hemodynamic parameters (SV, CO, and TPR) as predictors of positive tilt test response with receiver-operating characteristic curve analysis. CONCLUSIONS: Our results show that, 2 minutes after nitroglycerin administration, a statistically significant decrease of SV values (<67 mL) strongly predicts (area under the curve, 0.985; P < 0.0001) the HUTT-positive response in healthy patients with recurrent unexplained syncope.

Chronic Effects of Different Intensities of Interval Training on Hemodynamic, Autonomic and Cardiorespiratory Variables of Physically Active Elderly People.

Interval training (IT) is a very efficient method. We aimed to verify the chronic effects of IT with different intensities on hemodynamic, autonomic and cardiorespiratory variables in the elderly. Twenty-four physically active elderly men participated in the study and were randomized into three groups: Training Group A (TGA, n = 8), Training Group B (TGB, n = 8) and control group (CG, n = 8). The TGA and TGB groups performed 32 sessions (48 h interval). TGA presented 4 min (55 to 60% of HRmax) and 1 min (70 to 75% of HRmax). The TGB training groups performed the same protocol, but performed 4 min at 45 to 50% HRmax and 1 min at 60 to 65% HRmax. Both training groups performed each set six times, totaling 30 min per session. Assessments were performed pre (baseline) after the 16th and 32nd intervention session. The CG performed only assessments. Hemodynamic, autonomic and cardiorespiratory (estimated VO2max) variables were evaluated. There were no significant differences between protocols and times (p > 0.05). However, the effect size and percentage delta indicated positive clinical outcomes, indicating favorable responses of IT. IT may be a strategy to improve hemodynamic, autonomic and cardiorespiratory behavior in healthy elderly people.

Assessing rupture risk by hemodynamics, morphology and plasma concentrations of the soluble form of tyrosine kinase receptor Axl in unruptured intracranial aneurysms.

OBJECTIVE: This study investigated the relationship between morphology, hemodynamic parameters, and plasma concentrations of the soluble form of tyrosine kinase receptor Axl (sAxl) and their potential role in assessing the intracranial aneurysm rupture risk. METHODS: Thirty-nine patients were retrospectively recruited and these patients were divided into low and high rupture risk groups based on the PHASES score. Plasma levels of sAxl were measured using an enzyme-linked immunosorbent assay-based method. Computational fluid dynamics were used to calculate the morphological and hemodynamic parameters. Differences between clinical data, morphological-hemodynamic parameters and sAxl level were initially determined using univariate analysis. The variables (p ＜ 0.05) were included in a logistic regression model, and the specificity and sensitivity of the selected parameters were evaluated both graphically and statistically using receiver operating characteristic (ROC) curve methods. RESULTS: Aneurysm size ratio (p = 0.023), and normalized wall shear stress (WSS) (p = 0.02) showed significant differences between the two groups. Plasma concentrations of sAXL with a high rupture risk were significantly higher than the low rupture risk (8.47 ± 4.43 ng/ml vs. 5.37 ± 3.21 ng/ml; p = 0.016). Binary logistic regression analysis indicated that the concentration of sAxl was an independent determinant of high rupture risk (odds ratio=1.41, 95%CI=1.08-1.83, p = 0.011). The combination of sAxl + size ration (SR) + WSS achieved the highest area under the curve (0.849) for predicting rupture risk. CONCLUSIONS: Unruptured intracranial aneurysms with a higher rupture risk had a larger SR, lower WSS, and higher plasma sAxl concentration. Combining sAxl, SR, and WSS could help estimate the rupture risk of intracranial saccular aneurysm.

Comparative Evaluation of Effectiveness of 2% Lignocaine Hydrochloride with Clonidine Hydrochloride versus 2% Lignocaine Hydrochloride with Adrenaline Bitartrate as Local Anesthetic for Adult Patients Undergoing Surgical Extraction of Impacted Mandibular Third Molars: A Randomized Controlled Clinical Study.

BACKGROUND AND OBJECTIVES: Clonidine is a common additive to local anesthetics for various regional and local nerve blocks. However, its effectiveness in dentistry has not yet been fully explored. Thus, this study was performed to evaluate the quality of anesthesia, vasoconstrictive effects, hemodynamic response, and pain control using a solution of 2% lignocaine hydrochloride with clonidine hydrochloride in comparison with the standard solution of 2% lignocaine hydrochloride and adrenaline bitartrate for pterygomandibular nerve blocks. MATERIALS AND METHODS: A parallel arm, triple-blind randomized controlled study was conducted on 152 patients belonging to ASA-I (American Society of Anesthesiologists) category in the age group of 18-45 years, requiring surgical extraction of impacted mandibular third molars. The patients were divided equally into two groups randomly by computer-generated sequence; Group 1: 2% lignocaine hydrochloride with 1 ml of clonidine hydrochloride (150 µg/ml) and Group 2: 2% lignocaine hydrochloride with adrenaline bitartrate 1: 80,000 (12.5 µg/ml). The variables evaluated were systolic, diastolic, and mean arterial blood pressures, heart rate (HR), blood loss, onset, depth (pain), and duration of anesthesia. RESULTS: There was a statistically nonsignificant difference seen between the two groups (P > 0.05) for the onset of anesthesia, pain assessed, and blood loss, whereas a statistically highly significant difference was seen for cardiovascular variables (systolic, diastolic and mean arterial blood pressures, and HR) at various intervals with higher values for Group 2 (P < 0.001) and for the duration of action of local anesthesia (LA), with higher values for Group 1 (P < 0.001). CONCLUSIONS: Clonidine as an additive to lignocaine has proved to have the onset of action, vasoconstrictive properties, and pain control, equivalent to adrenaline. However, with better stability of hemodynamic variables and prolonged duration of action of LA with clonidine, it can be considered as a better, safer, and more effective additive to lignocaine than adrenaline.

The effects of hemodynamic monitoring using the PiCCO system on critically ill patients.

OBJECTIVE: We aimed to evaluate the effects of hemodynamic monitoring using the pulse index continuous cardiac output (PiCCO) system with critically ill patients. METHODS: In total, 292 patients with primary physiological abnormalities of hypotension (n = 180) or hypoxemia (n = 112) were evaluated. The attending physicians completed a questionnaire before each catheterization. After each catheterization, the attending physicians reviewed each chart to determine the possibility of altering the therapy. RESULTS: In the hypotension subgroup, the attending physicians showed less accuracy in predicting the global end-diastolic index values (23.9%, 43/180), with a significant difference, and more accuracy in predicting the extravascular lung water index values (58.9%, 66/112), without a significant difference from the patients in the hypoxemia subgroup. In the hypotension patients, the lactate clearance rate within 6 h was significantly higher (36.4 ± 9.6 vs 21.3 ± 9.5; P<0.0001) when the hemodynamic monitoring led to therapeutic changes. CONCLUSIONS: The hemodynamic variables obtained using the PiCCO system improved the accuracy of the bedside evaluations and led to alterations in the therapeutic plans, particularly among the hypotension patients. The therapy changes showed no improvement in the overall mortality but were associated with improved tissue perfusion among the hypotension patients.

The effects of volume-controlled ventilation versus pressure-controlled ventilation on hemodynamic and respiratory parameters in patients undergoing lumbar spine fusion surgery: a randomized controlled trial.

BACKGROUND: Hypotension is a common event in patients under general anesthesia during lumbar spine fusion surgery. The reduction of venous drainage followed by the postural changes is the main reason. The venous return reduced when the intrathoracic pressure is positive. Volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) are two traditional ventilation modes in operating room, with different respiratory mechanics. The two ventilation modes have different influences on intrathoracic pressure and consequently venous return. A double-blinded, randomized, parallel group controlled clinical trial was conducted to examine the hemodynamic and respiratory effects of two different ventilation modes in lumbar spine fusion surgery. METHODS: Forty-eight patients scheduled for posterior lumbar spine fusion surgery at Zhongda Hospital, Southeast University were randomly allocated into two groups to receive either the VCV mode or PCV mode [vital volume (VT) 8 mL/kg, and partial pressure of end-tidal carbon dioxide (PETCO2) 35-45 mmHg]. The respiratory mechanics [peak airway pressure (Ppeak) and dynamic compliance (Cdyn)] and hemodynamic changes were measured every 10 min for 120 min. All participants and relevant staff were blinded to the randomization. RESULTS: The data of 19 of 22 patients in the VCV group and 18 of 20 in the PCV group were analyzed. Compared to VCV group, cardiac output (CO) and central venous pressure (CVP) in the PCV group were higher; however, the difference was not significant. There's no statistically difference in systemic vascular resistance index (SVRI) values of both the groups. The mean blood pressure (MBP) of the PCV group was higher than that of the VCV group from 90 min after the patients were turned to the prone position until the endpoint. The Cdyn and Ppeak of the PCV group were higher than those of the VCV group. Additionally, there was a positive correlation between Cdyn and CO (r=0.744, P=0.006). CONCLUSIONS: With better respiratory mechanic and hemodynamic stability, PCV was a better choice for patients undergoing lumbar spine fusion surgery. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-TRC-14005086.

Hemodynamic Changes During Surgical Decompression in Traumatic Brain Injury Patients.

OBJECTIVE: To understand the hemodynamic changes that occur with surgical decompression of lesions caused by traumatic brain injury. METHODS: In this prospective, observational study, patients with traumatic brain injury requiring craniotomy within 48 hours of injury were recruited. Cardiac index (CI), stroke volume index, stroke volume variation, systemic vascular resistance index (SVRI), heart rate, and mean arterial pressure were monitored throughout surgery using a FloTrac transducer. Standard anesthetic and surgical regimens were followed. RESULTS: Hemodynamic data in 107 patients were compared before skin incision and after hematoma decompression (comparable anesthetic state). There was a significant increase in CI and stroke volume index and a decrease in SVRI and mean arterial pressure following surgical decompression. On subgroup analysis based on preincision CI, the changes were similar in patients with low and normal CI, whereas in patients with high CI, SVRI did not decrease significantly. High preincision CI with no change in SVRI with decompression was associated with poor neurologic outcome at discharge. CONCLUSIONS: In patients with TBI, surgical decompression leads to an increase in CI and a decrease in mean arterial pressure owing to a decrease in SVRI in patients with preincision low or normal cardiac output. These changes were not seen in patients with preincision high CI, and such patients had a poor neurologic outcome.

Autonomic function and its relationship with central obesity and hemodynamic variables in obese and overweight adults / Función autonómica y su relación con la obesidad central y las variables hemodinámicas en adultos obesos y con sobrepeso

Introduction: central obesity is associated with an autonomic dysfunction characterized by an increase in sympathetic activity and a reduction in vagal tone, leading to a decrease in heart rate variability. Objective: we aimed to analyze the relationship between the time and frequency domains of heart rate variability with central obesity, and its hemodynamic variables in normal-weight, overweight and obese adults. Methods: a total of 65 adults were evaluated (25.4 ± 3.2 years old) and distributed in 3 groups: normal weight group (NW group), overweight group (OW group) and obese group (OB group). Heart rate variability parameters at rest and both anthropometric and hemodynamic variables were recorded. Results: the results showed a positive correlation between waist circunference and LF/HF ratio in the OW (p = 0.0008; r = 0.6607; r2 = 0.4365) and OB (p = 0.0001; r = 0.8286; r2 = 0.6866) groups. The waist-to-height ratio showed significant differences with HF in the NW, OW, and OB groups. The variables related to the parasympathetic system (SDNN, RMSSD, pNN50, HF) in the OB and OW groups showed a decrease in values when compared to the NW group. Likewise, the variable related to the sympathetic system (LF) in the OB and OW groups increased its values when compared with the NW group. The LF/HF ratio increased from the NW group to the OW and OB groups (1.6 ± 0.7; 2.5 ± 1.8 and 3.3 ± 0.7). Conclusion: overweight and obese adults present a modulation of sympathetic activity predominance at rest. This increased activity is represented by the time and frequency domains of heart rate variability, having an important correlation with waist circumference and waist-to-height ratio (AU)

Introducción: la obesidad central se asocia con una disfunción autonómica caracterizada por una mayor actividad simpática y reducción del tono vagal, conduciendo a una disminución de la variabilidad de la frecuencia cardíaca (VFC). Objetivo: analizar la relación entre los dominios de tiempo y frecuencia de la VFC con la obesidad central y sus variables hemodinámicas en adultos con peso normal, sobrepeso y obesidad. Metodología: participaron 65 adultos (25,4 ± 3,2 años) distribuidos en 3 grupos: peso normal (grupo NW), sobrepeso (grupo OW) y obesidad (grupo OB). Se registraron los parámetros de la VFC y las variables antropométricas y hemodinámicas. Resultados: se observó una correlación positiva entre la circunferencia de la cintura y la relación LF/HF en el grupo OW (p = 0,0008; r = 0,6607; r2 = 0,4365) y OB (p = 0,0001; r = 0,8286; r2 = 0,6866). La relacion cintura/altura mostró una diferencia significativa con la HF en los grupos NW, OW y OB. La actividad parasimpática (SDNN, RMSSD, pNN50, HF) de los grupos OB y OW evidenció una disminución de los valores en comparación con el grupo NW. La actividad simpática (LF) en el grupo OB y OW presentó mayores valores que en el grupo NW. La relación LF/HF aumentó del grupo NW hacia el OW y el OB (1,6 ± 0,7; 2,5 ± 1,8 y 3,3 ± 0,7). Conclusiones: el sobrepeso y la obesidad presentan una predominancia de la actividad simpática en reposo. Este aumento de la actividad está representado en el dominio de tiempo y frecuencia de la VFC y, además, presenta una correlación importante con la circunferencia de la cintura y la relación cintura/altura (AU)

Repercusión hemodinámica del cierre de la fístula arteriovenosa sobre el corazón derecho en trasplantados renales / Hemodynamic impact of arteriovenous fistula closure on the right heart in kidney transplant patients

Introducción: Las complicaciones cardiovasculares constituyen la primera causa de morbilidad y mortalidad en el receptor de trasplante renal. Objetivo: Caracterizar la repercusión de la fístula arteriovenosa sobre variables hemodinámicas del corazón derecho en trasplante renal. Métodos: Estudio prospectivo, longitudinal. Se incluyeron 52 pacientes, evaluados clínica y ecocardiográficamente. Se compararon cinco variables hemodinámicas en el corazón derecho, previos y seis meses posteriores al cierre de la fístula arteriovenosa. Resultados: La edad promedio 46,02 años, 29 masculinos (55,8 por ciento). El diámetro de la aurícula derecha en las fístulas cerradas en la muñeca izquierda 8805; 6 años disminuyó (p=0,044), al igual que en el ventrículo derecho <6 años a nivel del pliegue del codo izquierdo (p=0,004). La presión sistólica de la arteria pulmonar descendió tras el cierre en el codo izquierdo lt;6 años (p=0,002), en las 8805;6 (p=0,05) y en el derecho (p=0,006). La presión media de la arteria pulmonar se redujo en las cerradas en pliegue del codo izquierdo <6 años (p=0,001) y 8805;6 años (p=0,017) al igual que en el derecho (p=0,009). La fracción de eyección del ventrículo derecho se incrementó al cierre en muñeca izquierda ;6 años (p=0,046) y en el codo derecho 8805;6 años (p=0,027). Conclusiones: La permanencia de la fístula arteriovenosa en el receptor de trasplante renal contribuye a la perpetuación y progresión de la disfunción cardiovascular preexistente(AU)

Introduction: Cardiovascular complications are the leading cause of morbidity and mortality in kidney transplant recipients. Objective: To describe the consequence of arteriovenous fistula on hemodynamic variables of the right heart in kidney transplantation. Methods: We conducted a prospective, longitudinal study. Fifty two patients were included, and they were clinically and echocardiographically assessed. Five hemodynamic variables were compared in the right heart, prior to the closure of the arteriovenous fistula and six months after. Results: The average age was 46.02 years, 29 were male (55.8 percent). The diameter decreased in the right atrium in closed fistulas in the left wrist #8805; 6 years (p = 0.044). The same occurred in the right ventricle <6 years at the level of the left elbow crease (p = 0.004). The systolic pressure of the pulmonary artery decreased after closure in the left elbow <6 years (p = 0.002), in ≥6 (p = 0.05) and in the right (p = 0.006). The mean pressure of the pulmonary artery was reduced in those closed in the crease of the left elbow <6 years (p = 0.001) and ≥6 years (p = 0.017) as well as in the right (p = 0.009). The right ventricular ejection fraction increased at closure in the left wrist <6 years (p = 0.046) and in the right elbow ≥6 years (p = 0.027). Conclusions: The permanence of arteriovenous fistula in the kidney transplant recipient contributes to the perpetuation and progression of the pre-existing cardiovascular dysfunction(AU)

The hemodynamic changes by different end-tidal CO2 under anesthesia using sevoflurane-N2O.

BACKGROUND: Hypercapnia augments cardiac output and can initiate a sympathetically mediated release of catecholamines to increase cardiac output. Many studies of hemodynamic changes by hypercapnia under general anesthesia with inhalation anesthetics besides sevoflurane. This study examined the hemodynamic changes by increasing end-tidal carbon dioxide (EtCO2) under sevoflurane-N2O anesthesia. METHODS: Twenty patients were enrolled in the study. We studied stable, mechanically ventilated patients under general anesthesia maintained with O2 2 L/min - N2O 2 L/min - sevoflurane (1.5-2.5 vol%). Hypercapnia were obtained by reducing tidal volume and respiratory rate. EtCO2 was adjusted to 30, 40, 50 mmHg with each concentration maintained for 15 min. Global hemodynamic variables were monitored with a pulmonary artery catheter. RESULTS: There were no changes in mean arterial pressure or heart rate by hypercapnia. Acute moderate hypercapnia increased cardiac output (4.9 +/- 1.7, 5.5 +/- 1.7, 6.2 +/- 2.1 L/min; P < 0.05), cardiac index (3.0 +/- 0.9, 3.4 +/- 0.9, 3.8 +/- 1.1 L/min/m2; P < 0.05), pulmonary artery pressure (16.9 +/- 3.7, 19.6 +/- 4.2, 23.0 +/- 4.7 mmHg), but did not decrease systemic vascular resistance (1,558.3 +/- 500.4, 1,423.5 +/- 678.6, 1,156.8 +/- 374.0 dynes.sec/cm5; P > 0.05). CONCLUSIONS: When we changed patient EtCO2 to 30, 40, and 50 mmHg, there were no changes in mean arterial blood pressure and heart rate, but systemic vascular resistance decreased, and cardiac output, cardiac index and mean pulmonary arterial pressure increased significantly.

The hemodynamic changes by different end-tidal CO2 under anesthesia using sevoflurane-N2O / 대한마취과학회지

BACKGROUND: Hypercapnia augments cardiac output and can initiate a sympathetically mediated release of catecholamines to increase cardiac output. Many studies of hemodynamic changes by hypercapnia under general anesthesia with inhalation anesthetics besides sevoflurane. This study examined the hemodynamic changes by increasing end-tidal carbon dioxide (EtCO2) under sevoflurane-N2O anesthesia. METHODS: Twenty patients were enrolled in the study. We studied stable, mechanically ventilated patients under general anesthesia maintained with O2 2 L/min - N2O 2 L/min - sevoflurane (1.5-2.5 vol%). Hypercapnia were obtained by reducing tidal volume and respiratory rate. EtCO2 was adjusted to 30, 40, 50 mmHg with each concentration maintained for 15 min. Global hemodynamic variables were monitored with a pulmonary artery catheter. RESULTS: There were no changes in mean arterial pressure or heart rate by hypercapnia. Acute moderate hypercapnia increased cardiac output (4.9 +/- 1.7, 5.5 +/- 1.7, 6.2 +/- 2.1 L/min; P 0.05). CONCLUSIONS: When we changed patient EtCO2 to 30, 40, and 50 mmHg, there were no changes in mean arterial blood pressure and heart rate, but systemic vascular resistance decreased, and cardiac output, cardiac index and mean pulmonary arterial pressure increased significantly.