Similar Hemodynamic Changes Research Articles

Hot head-out water immersion increases internal carotid artery shear rate but does not alter intracranial vascular reactivity to carbon dioxide

Acute head-out water immersion (HOWI) in hot water increases cerebral blood flow (CBF) until core temperature rises by ~1.0°C. The increase in CBF may promote increases in arterial shear rate that could enhance cerebrovascular reactivity to CO2 (CVRCO2) as a result of elevated nitric oxide (NO) bioavailability. An increase in NO bioavailability improves peripheral vasodilator function, and therefore, a similar response may occur in the cerebral vasculature. This likely only aids in cerebral vasodilation during hypercapnia, and not cerebral vasoconstriction during hypocapnia. However, it is unclear if a single session of hot HOWI alters cerebral artery shear rate and CVRCO2 to hyper- and hypocapnia. Purpose: We tested the hypotheses that during a single session of hot HOWI (39°C), cerebral artery shear rate and hypercapnic CVRCO2 would be greater and hypocapnic CVRCO2 would be lower compared to temperate HOWI (35°C). Methods: Eighteen healthy participants (age: 25±5 y, 6 women) completed two experimental visits. Middle and posterior cerebral artery blood velocities (transcranial Doppler; MCAv and PCAv) were continuously recorded. Blood velocities and diameters of the right internal carotid artery (ICA) and vertebral artery (VA) were obtained via dual-mode Doppler ultrasound to calculate shear rate. Hypocapnic and hypercapnic CVRCO2 were assessed in the MCA and PCA during self-paced hyperventilation (until PETCO2 decreased by 10 mmHg from baseline) and during 30 s of 7% CO2 inhalation, respectively. Measures were completed before immersion (PRE) and after a +1.0°C increase in core temperature during hot HOWI and time-matched during temperate HOWI. Data are reported as mean ± SD. Results: There were no differences between conditions at PRE. MCAv (55±9 vs. 64±12 cm/s; P=0.01) and PCAv (29±5 vs. 39±7 cm/s; p<0.01) were lower in hot vs. temperate HOWI at +1.0°C. ICA shear rate was greater in hot vs. temperate HOWI at +1.0°C (247±51 vs. 180±43 s−1; p<0.01) but VA shear rate did not differ between conditions (P=0.78). There were no differences between conditions for hypercapnic CVRCO2 (MCA: P =0.48, PCA: P=0.43) or hypocapnic CVRCO2 (MCA: P=0.18). A condition effect was observed for PCA hypocapnic CVRCO2 (p<0.01), but multiple comparisons did not reveal where differences occurred (all P≥0.10). Conclusion: Hot head out water immersion elicits similar changes in hemodynamics and CVRCO2 in intracranial arteries (i.e., MCA and PCA) as temperate head out water immersion. Hot head out water immersion produces a greater shear rate in the ICA compared to temperate water, which may be beneficial for cerebrovascular health if done recurrently. This study was partially supported by the Mark Diamond Research Fund at the University at Buffalo and the Offce of Naval Research Director of Research Early Career Grant (N00014-17-1-2878). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Efficacy of gargling with Licorice extract, Ketamine, and Magnesium Sulfate before Laryngoscopy: Tracheal Intubation in Prevention of Sore Throat, Hoarseness, and Cough; a Randomized Clinical Trial

Background and objective: Tracheal intubation is considered to represent a major cause of trauma to the airway mucosa, which can give rise to a postoperative sore throat. This randomized clinical quality improvement trial on the well-established benefit of gargling with licorice extract, ketamine, and magnesium sulfate before laryngoscopy and tracheal intubation was undertaken to address how to prevent throat soreness, hoarseness, and cough. Patients and methods: In a prospective, double-blind randomized controlled trials, 105 patients who were undergoing laryngoscopy and endotracheal intubation under general anesthesia were recruited. They were assigned into one of three intervention groups, including ketamine, licorice, and magnesium sulfate, using block randomization and requested to gargle twice for 15 seconds and 20 minutes before anesthesia induction and to spit out. Postoperative sore throat, cough, and hoarseness were recorded from endotracheal extubation at baseline (T0) every 10 minutes during recovery until T45 (45 minutes) and at initial 24-hour time points (2, 4, 8, 12, and 24 hours) later. Analysis of variance (ANOVA) and chi-squared tests was used for data analysis at a significance level of p = 0.05 in Statistical Package for the Social Sciences (SPSS) v20 (Chicago, Illinois, United States of America) software. Results: The mean age of patients was 48.21 ± 9.21 years, and 57.1% were male. No statistically significant intergroup difference was observed in the study groups for oxygen saturation (SpO2), heart rate, blood pressure, and duration of surgery. Our results showed that less sore throat was found in the ketamine group at T8/T12 (8 and 12 hours after recovery (p < 0.05). In addition, no statistically significant intergroup difference was revealed in cough and hoarseness during the times studied (p > 0.05). Conclusion: Our evidence confirmed that ketamine, licorice, and magnesium sulfate appeared to be able to effectively reduce pain, cough, and hoarseness and to be associated with similar hemodynamic changes, while the ketamine-treated subjects manifested a marked decrease in sore throat pain intensity with postoperative times of T8 and T12. Consequently, gargling with ketamine continues to demonstrably be put forward as a promising candidate to control postoperative sore throat but is as equal as other intervention drugs in terms of effectively controlling cough or hoarseness. Ultimately, the final choice relies on both patient acceptance and anesthesiologist preference.

“EFFECT OF SUBHYPNOTIC DOSES OF MIDAZOLAM AND PROPOFOL FOR NAUSEAAND VOMITING DURING SPINALANESTHESIA FOR CESAREAN SECTION”

Introduction: Intra-operative nausea and vomiting is a common yet disturbing side effect associated with spinal anesthesia for cesarean section. In this prospective double blind study, comparision of effect of subhypnotic doses of Propofol and Midazolam on nausea and vomiting was done. Materials and Methods: The prospective randomized study was carried out in 60 parturients of ASA grade I &II of age groups between 20-35 years posted for cesarean section. They were divided into 2 groups of 30 each. The hemodynamic changes,nausea and vomiting scores, sedation scores were assessed and compared. Result: The parturients who received low dose of Propofol after delivery experienced less nausea and vomiting compared to parturients who received Midazolam. Conclusion: Subhypnotic Dose of propofol signicantly decreases intraoperative nausea and vomiting in caesarean section under spinal anesthesia compared to subhypnotic dose of midazolam, with acceptable sedation and similar haemodynamic changes

Erector spinae plane block for postoperative analgesia following percutaneous nephrolithotomy under spinal anaesthesia- A randomised controlled study.

Postoperative pain is a multitude of various irksome sensory, emotional and mental experiences aggravated by surgical trauma and associated with autonomic, endocrine, metabolic, physiological and behavioural responses. The aim of this study was to evaluate the effect of erector spinae plane block (ESPB) in postoperative analgesia following percutaneous nephrolithotomy (PCNL) under spinal anaesthesia. This prospective randomised study was conducted on sixty American Society of Anesthesiologists physical status I and II patients scheduled for PCNL under spinal anaesthesia. They were randomised into two equal groups of thirty patients. ESPB was given in group A with 20 ml of injection bupivacaine 0.25% and dexamethasone 8 mg and group B received injection tramadol 1.5 mg/kg intravenously immediately after PCNL. The primary outcome was comparison of visual analogue scale (VAS) score in the first 24 h postoperatively, whereas secondary objectives included hemodynamic variables and requirement of rescue analgesia. VAS score in group A (ESPB) with mean of 3.15 ± 0.68 was comparatively low when compared to group B with mean of 6.61 ± 0.50 at 6 hours. After 4 h postoperatively, VAS scores continued to be higher and significant number of patients required rescue analgesia in group B. ESPB reduced VAS score, provided adequate postoperative analgesia, with similar haemodynamic changes and adverse effects in comparison to the conventional analgesia with tramadol in PCNL.

Abstract 10678: Structural and Functional Changes of the Right Ventricle in Sprague Dawley and Wistar Rat Models of Pulmonary Arterial Hypertension

Introduction: Assessment of right ventricle (RV) function and structure are essential to determine the efficacy of new PAH drugs preclinically. This study compared RV function, structure, and hemodynamics in response to monocrotaline (MCT) in Sprague Dawley (SD) and Wistar rats. Methods: SD and Wistar rats (194-243 g) were administered either 0.9% NaCl or MCT (60 mg/kg) on Day 0. On Day 23, RV function and structure were evaluated by echocardiography. On Day 24, RV pressure-volume relations were assessed, and heart and lung weights were collected. Results: MCT treatment resulted in dilated RV hypertrophy in both strains, but the magnitude of changes were different between strains. RV internal diameter during diastole (61%, p=0.0003) and systole (67%, p=0.001), RV end-diastolic (51%, p<0.0001) and systolic (80%, p<0.0001) area were greater in MCT/SD than MCT/Wistar. MCT/SD also showed increased right atrial area (110%, p=0.0002) vs. MCT/Wistar. Due to increased load, MCT/SD tended to develop a thicker RV free wall (22%, p>0.05) than MCT/Wistar. Systolic dysfunction was observed with MCT treatment in both strains; however, the MCT/SD showed a greater decrease in RV fractional area change (-51%, p=0.009) than MCT/Wistar. The tricuspid annular velocity and annular plane systolic excursion were slightly decreased in MCT/SD compared to MCT/Wistar (p=NS). RV catheterization showed similar MCT-induced increases in RV end systolic and diastolic pressures in both strains. However, the decrease in cardiac output was more pronounced in MCT/SD (-30%, p<0.0001) than in MCT/Wistar. Increase in RV weight normalized by tibia length (RV/TL) and Fulton’s Index was observed with MCT treatment; but the degree of hypertrophy was more pronounced in MCT/SD (57% RV/TL and 37% Fulton’s Index) than MCT/Wistar. Conclusions: Our results showed that while similar hemodynamic changes were observed in SD and Wistar rats in response to MCT, the magnitude of dilated RV hypertrophy and systolic impairment was exacerbated in SD vs. Wistar rats.

Spikes with and without concurrent high-frequency oscillations: Topographic relationship and neural correlates using EEG-fMRI

ObjectiveEpilepsy surgery is the best therapeutic option for patients with drug-resistant focal epilepsy. During presurgical investigation, interictal spikes can provide important information on eligibility, lateralisation and localisation of the surgical target. However, their relationship to epileptogenic tissue is variable. Interictal spikes with concurrent high-frequency oscillations (HFOs) have been postulated to reflect epileptogenic tissue more reliably. Here, we studied the voltage distribution of scalp-recorded spikes with and without concurrent HFO and identified their respective haemodynamic correlates using simultaneous electroencephalography and functional Magnetic Resonance Imaging (EEG-fMRI). MethodsThe scalp topography of spikes with and without concurrent HFOs were assessed in 31 consecutive patients with focal drug-resistant epilepsy who showed interictal spikes during presurgical evaluation. Simultaneous EEG-fMRI was then used in 17 patients with spikes and concurrent HFOs. Haemodynamic changes were obtained from the spatial correlation between the patient-specific voltage map of each spike population and the intra-scanner EEG. The haemodynamic response of spikes with and without HFOs were compared in terms of their spatial similarity, strength, the distance between activation peaks and concordance with interictal localisation. ResultsTwenty-five patients showed spikes with and without concurrent HFOs. Among patients with both types of spikes, most spikes were not associated with HFOs (p < 0.0001, Mann-Whitney test). Twenty of the 25 patients showed an average of 8 ± 6 (standard deviation) electrodes with significant voltage differences (p = 0.025, permutation test corrected for multiple comparisons) on scalp electrodes within and distant to the spike field.Comparing the haemodynamic response between both spike populations, we found no significant differences in the peak strength (p = 0.71, Mann-Whitney test), spatial distribution (p = 0.113, One-sample Wilcoxon test) and distance between activation peaks (p = 0.5, One-sample Wilcoxon test), with all peaks being co-localised in the same lobe. SignificanceOur data showed that spikes with and without HFOs have different scalp voltage distributions. However, when assessing the haemodynamic changes of each spike type, we found that both elicit similar haemodynamic changes and share high spatial similarity suggesting that the epileptic networks of spikes with and without HFOs have the same underlying neural substrate.

Comparison of spinal versus caudal epidural anesthesia in the management of patients undergoing ambulatory perianal surgery: Randomized, prospective study

Objective: To compare levobupivacaine based caudal epidural anesthesia and spinal anesthesia in terms of Intraoperative hemodynamic changes and postoperative pain and patient comfort in subjects undergoing perianal surgery in outpatient setting. Material and methods: All consecutive patients who were scheduled for perianal surgery. The difference in intraoperative hemodynamic changes, sensory and motor block level, postoperative pain and patient comfort was the primary outcome measure of this study. Results: There were no significant differences between the groups in terms of mean arterial pressure and heart rate recorded. Subjects randomized to spinal anesthesia had a significantl extensive motor and sensory block compared to those randomized to caudal epidural anesthesia. Visual analogue scale scores for surgical pain at postoperative 12 hours was significantly higher in subjects receiving spinal anesthesia compared to those receiving caudal epidural anesthesia (p< 0.05). Time to first analgesic administration was significantly lower in subjects randomized to spinal anesthesia compared to those receiving caudal epidural anesthesia (p< 0.01). Conclusion: Spinal anesthesia is associated with more extensive sensory and motor block compared to caudal epidural anesthesia in patients undergoing perianal surgery. Both techniques lead to similar hemodynamic changes. Postoperative pain control is more favorable with caudal block than the spinal anesthesia.

Angiotensin II-induced natriuresis is attenuated in knockout mice lacking the receptors for tumor necrosis factor-α.

Intravenous infusion of relatively higher doses of angiotensin II (AngII) elicits natriuresis as opposed to its usual anti‐natruretic response. As AngII can induce tumor necrosis factor‐α (TNFα) production which elicits natriuresis via its action on TNFα receptor type 1 (TNFR1), we hypothesize that the concomitant release of TNFα contributes to the natriuretic response to AngII. Responses to AngII infusion (1 ng min−1 g−1 for 75 min, iv) were evaluated in anesthetized knockout (KO) mice lacking TNFR1 (n = 6) and TNFR2 (TNFα receptor type 2; n = 6) and compared these responses with those in wild type (WT; n = 6) mice. Arterial pressure (AP) was recorded from a cannula placed in the carotid artery. Renal blood flow (RBF) and glomerular filtration rate (GFR) were measured by PAH and inulin clearances, respectively. Urine was collected from a catheter placed in the bladder. AngII caused similar increases (p < 0.05 vs basal values) in AP (WT, 37 ± 5%; TNFR1KO, 35 ± 4%; TNFR2KO, 30 ± 4%) and decreases (p < 0.05) in RBF (WT, −39 ± 5%; TNFR1KO, −28 ± 6%; TNFR2KO, −31 ± 4%) without significant changes in GFR (WT, −17 ± 7%; TNFR1KO, −18 ± 7%; TNFR2KO, −12 ± 7%). However, despite similar changes in AP and renal hemodynamics, AngII induced increases (p < 0.05) in urinary sodium excretion in WT (3916 ± 942%) were less in the KO strains, more or less in TNFR1KO (473 ± 170%) than in TNFR2KO (1176 ± 168%). These data indicate that TNF‐α receptors, particularly TNFR1 are involved in the natriuretic response that occur during acute infusion of AngII and thus, plays a protective role in preventing excessive salt retention at clinical conditions associated with elevated AngII level.

Combined spinal epidural anesthesia in obese parturients undergoing cesarean surgery

There is asignificant increase in number of obese pregnant women worldwide. Obese parturients undergoing cesarean section have a higher risk for hypotension and require higher doses of vasopressors following spinal anesthesia compared to nonobese parturients. This study aimed to compare the maternal hemodynamic changes when combined spinal-epidural anesthesia (CSEA) is induced in the left lateral decubitus and sitting positions in obese pregnant women undergoing elective cesarean section. In this study, pregnant women with full-term gestation diagnosed as obese undergoing elective cesarean section were included. Two groups were formed: the CSEA was performed in left lateral position in groupI (n = 50) and in sitting position in groupII (n = 50). At the end of the CSEA procedure, patients were placed in the supine position. When the sensory block reached at the upper level of T6 dermatome, surgery was initiated. Hemodynamic, anesthetic and neonatal parameters were recorded. In all patients, CSEA was successful and sufficient anesthesia was provided for surgery. Time to reach T6 dermatome sensory level in groupII was found to be longer than groupI (P = 0.011). At 20 min after spinal injection, the maximum sensory block level was similar in both groups. There were no significant differences between groups in terms of sensory block time and the time to requiring postoperative supplemental analgesics. There were no significant differences in terms of the volume of intravenous fluid administered, ephedrine and atropine requirements between groups. Both groups had similar systolic blood pressure, heart rate and oxygen saturation values during surgery and postoperatively. While both groups had similar diastolic blood pressure (DBP) values during surgery and at the 1st postoperative hour, groupII had lower DBP values at the 2nd postoperative hour compared with groupI (P = 0.04). Left lateral decubitus and sitting positions during performance of CSEA lead to similar maternal hemodynamic changes in obese pregnant women undergoing cesarean section.

Cortical and subcortical hemodynamic changes during sleep slow waves in human light sleep

EEG slow waves, the hallmarks of NREM sleep are thought to be crucial for the regulation of several important processes, including learning, sensory disconnection and the removal of brain metabolic wastes. Animal research indicates that slow waves may involve complex interactions within and between cortical and subcortical structures. Conventional EEG in humans, however, has a low spatial resolution and is unable to accurately describe changes in the activity of subcortical and deep cortical structures. To overcome these limitations, here we took advantage of simultaneous EEG-fMRI recordings to map cortical and subcortical hemodynamic (BOLD) fluctuations time-locked to slow waves of light sleep. Recordings were performed in twenty healthy adults during an afternoon nap. Slow waves were associated with BOLD-signal increases in the posterior brainstem and in portions of thalamus and cerebellum characterized by preferential functional connectivity with limbic and somatomotor areas, respectively. At the cortical level, significant BOLD-signal decreases were instead found in several areas, including insula and somatomotor cortex. Specifically, a slow signal increase preceded slow-wave onset and was followed by a delayed, stronger signal decrease. Similar hemodynamic changes were found to occur at different delays across most cortical brain areas, mirroring the propagation of electrophysiological slow waves, from centro-frontal to inferior temporo-occipital cortices. Finally, we found that the amplitude of electrophysiological slow waves was positively related to the magnitude and inversely related to the delay of cortical and subcortical BOLD-signal changes. These regional patterns of brain activity are consistent with theoretical accounts of the functions of sleep slow waves.

Short-term Effects of Hepatic Arterial Buffer Responses Induced by Partial Splenic Embolization on the Hepatic Function of Patients with Cirrhosis According to the Child-Pugh Classification.

Objective This study primarily aimed to investigate the short-term effects of partial splenic embolization (PSE) on the Child-Pugh score and identify predictive factors for changes in the score caused by PSE. The secondary aim was to analyze changes in various parameters at one month postoperatively using these identified factors. Methods Between September 2007 and December 2019, 118 patients with cirrhosis and hypersplenism underwent PSE at our hospital. Testing was conducted preoperatively and at one month after PSE. Results Overall, the Child-Pugh score was not significantly changed postoperatively. The Child-Pugh score before PSE was identified as the strongest independent predictor of ameliorated and deteriorated Child-Pugh scores after PSE. Higher pretreatment Child-Pugh scores were correlated with higher posttreatment amelioration rates of the score. A significant decrease in the portal vein diameter and a significant increase in the common hepatic artery diameter were evident at the same level postoperatively in 64 patients with Child-Pugh class A (group A) and in 54 patients with Child-Pugh class B or C (group B/C) preoperatively. According to Murray's Law, PSE resulted in decreased portal venous flow and increased hepatic arterial flow, suggesting a hepatic arterial buffer response (HABR) induced by the procedure. Despite equivalent splenic infarction rates and similar posttreatment changes in hepatic hemodynamics, PSE significantly increased the Child-Pugh score of group A; however, the procedure significantly decreased the score of group B/C. Conclusion Considering original portal venous-hepatic arterial hemodynamics, PSE is expected to produce HABR-mediated hepatic functional improvements in cirrhosis patients with Child-Pugh class B/C.

Cerebral hemodynamic changes during motor imagery and passive robot-assisted movement of the lower limbs

BackgroundNeurovascular Coupling is the cerebral mechanism responsible for linking neuronal activity, cerebral metabolism and regional cerebral blood flow (CBF). The direct relation between functional brain activity during active, passive and motor imagery paradigms and changes in CBF has been widely investigated using different techniques. However, CBF changes have not been investigated beat by beat during robot assisted passive movement (PM) and motor imagery (MI) of lower limb, yet. Materials and methodsWe investigated beat-to-beat hemodynamic changes in 8 healthy subjects using TCD during MI and robot-assisted PM of lower limb. ResultsThe results showed that MI and PM induce a significant CBFv increase and that PM and MI lead to similar hemodynamic changes in healthy subjects. ConclusionsThe findings may be useful to better understand the variation of CBFv in brain pathology and to develop more specific and efficient rehabilitation therapy protocols in neurological diseases, such as stroke.

Bupivacaine vs. Pethidine in Spinal Anesthesia of Old Patients: Haemodynamic Changes and Complications.

Organ changes during the aging are one of the signifi cant events in old patients. rthopedic surgeries are common operations in these patients that accompany with hemodynamic changes as blood pressure decrease, heart rate, and respiratory rate change. On the other hand, pain management of the ancient patients due to negative consequences as tachycardia, blood pressure increase, and myocardial ischemia is vital. Various types of opioid analgesics have been used in order to pain control in these patients. We decided to conduct the present study in order to compare the hemodynamic changes of the old patients who undergo lower limbs orthopedic surgeries by applying subarachnoid bupivacaine and meperidine (pethidine). Sixty-six patients older than 60 years included according to inclusion and exclusion criteria and randomly allocated into two same groups, Then in the fi rst group in the sitting posture by Quincke spinal needle 24 gauge, 12.5 mg of bupivacaine 0.5% (2.5 mL) injected in the subarachnoid space between L2-L3 or L3-L4. In the second group, in a same posture by applying the same spinal needle 24 gauge, 1 mg/kg of preservative-free pethidine injected in the subarachnoid space between L2-L3 or L3-L4. The patients evaluated for duration of anesthesia and analgesia, hemodynamic changes and complications such as headache, pruritus, shivering, urinary retention, and respiratory depression.. Thirty-two patients were males (48.5%) and 34 females (51.5%). There was no statistically signifi cant difference between groups in surgery types (p = 0.063). The duration of anesthesia was not different (p = 0.268) but the duration of analgesia was signifi cantly longer in pethidine group (p = 0.000). No statistically significant difference observed in any time of first 15 min up to 180 min following intervention in heart rate (p = 0.867). No statistical significant difference observed in blood pressure change between two groups (p = 0.605). The experience of headache was more common in the group of bupivacaine during and after the operation (p = 0.004 and 0.000, respectively). The need for pruritus treatment was more in the pethidine group (p = 0.016). However, the frequency of shivering during the operation was not signifi cant (p = 0.202), but after surgery was signifi cantly commoner in bupivacaine group (p = 0.001), but urinary retention and respiratory depression occurrence were not signifi cant (p = 0.228 and 0.720, respectively). By regarding different aspects of opioids use, it seems pethidine is more efficient due to longer analgesic time, similar hemodynamic changes, fewer headache, and shivering occurrence in comparison to bupivacaine in old patients.

An in vitro analysis of the PediMag and CentriMag for right-sided failing Fontan support

ObjectiveRight-sided mechanical circulatory support for failing Fontan physiology has been largely unsuccessful due to inherent hemodynamic differences between these patients and the target populations for most assist devices. This study uses advanced benchtop modeling of Fontan physiology to examine the use of PediMag and CentriMag to improve failing Fontan hemodynamics. MethodsEach device was attached to a compliance-matched, patient-specific total cavopulmonary connection in vitro model that used resistances, compliances, and programmable waveforms to establish “failing Fontan” baseline hemodynamics (cardiac output [CO] = 3.5 L/min and central venous pressure ∼17 mm Hg). The ability of the assist devices to improve failing Fontan hemodynamics (reduce inferior vena cava pressure and augment CO) was investigated. ResultsRequiring complete Fontan pathway restriction, PediMag reduced inferior vena cava pressure by ∼10 mm Hg and supported CO augmentation up to 5 L/min. This was accompanied by an increase in superior vena cava pressure of ∼6 mm Hg. CentriMag produced similar hemodynamic changes without the need for pathway restriction or an increase in superior vena cava pressure. ConclusionsPediMag and CentriMag right-sided support led to a decrease in inferior vena cava pressure and augmentation of cardiac output. In the case of CentriMag, this is accomplished without an increase in superior vena cava pressure or the need for restrictive banding. This work provides further data to help with the optimal design of a Fontan assist device to ameliorate the growing need.

Alternations of hemodynamic parameters during Chinese cupping therapy assessed by an embedded near-infrared spectroscopy monitor.

Cupping therapy is a promising method to cure or reduce the symptoms of some diseases including muscle pain/tendency/fatigue. Although the applications of cupping therapy have a thousand-year history in traditional Chinese medicine, the therapeutic effect of cupping is still questionable due to a lack of scientific evidence and the absence of physiological observations. In our previous study, we utilized near-infrared spectroscopy (NIRS) to assess the concentration change surrounding the cupping site and found a significant elevation in oxy-hemoglobin (HbO2). To further investigate the therapeutic effect of dry cupping treatment, we embedded a NIRS sensor into a suction cup to monitor the hemodynamic changes including HbO2, deoxy-hemoglobin ([Hb]) and blood volume on the cupping site in this study. Both a prominent elevation in [Hb] and a significant drop in [HbO2] in the tissue of the cupping site were observed during cupping. We also observed similar hemodynamic changes during post-cupping, which may demonstrate how cupping therapy works for treatment. This study showed that the embedding of NIRS sensor in a cupping system could offer a better understanding of the mechanism of cupping therapy.

Postoperative Development of Abdominal Compartment Syndrome among Patients Undergoing Endovascular Aortic Repair for Ruptured Abdominal Aortic Aneurysms

Abdominal compartment syndrome (ACS) has a reported incidence of 9%-14% among trauma patients. However, in patients with similar hemodynamic changes, the incidence of ACS remains unclear. Our aim was to determine the incidence of ACS among patients undergoing endovascular aortic repair (EVAR) for ruptured abdominal aortic aneurysms (rAAAs) and to identify associated risk factors. A retrospective review was performed for consecutive patients who underwent EVAR for rAAA from March 2010 to November 2016 at our institution. The development of ACS was diagnosed based on a variety of factors, including bladder pressure, laboratory abnormalities, hemodynamic monitoring, and clinical evaluation. Previously validated risk factors for ACS development in trauma and EVAR patients (preoperative hypotension, aggressive fluid resuscitation, postoperative anemia, use of an aorto-uniiliac graft, and placement of an aortic occlusive balloon) were analyzed. Association between patient characteristics and ACS development was analyzed using the Fisher's exact test. During the study period, 25 patients had image-confirmed rAAA and underwent emergent EVAR. Mortality rate was 28% (n=7), and ACS incidence was 12% (n=3). Of the analyzed risk factors, hypotension on arrival (P=0.037), transfusion of 3 or more units of packed red blood cells (P=0.037), and postoperative anemia (P=0.02) were all significantly associated with postoperative ACS development. In addition, having greater than 3 of the studied risk factors was associated with increased odds of developing ACS (P=0.015), and having greater than 4 of the studied risk factors showed the strongest association with ACS development (P=0.0017). Overresuscitation should be avoided in patients with rAAA. In addition, patients who present with multiple risk factors for ACS should be monitored very closely with serial bladder pressures and may require decompression laparotomy immediately after EVAR.

Clinical Study of Acute Vasoreactivity Testing in Patients with Chronic Thromboembolic Pulmonary Hypertension.

Background:The clinical significance of acute vasoreactivity testing (AVT) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) remains unclear. We analyzed changes in hemodynamics and oxygenation dynamics indices after AVT in patients with CTEPH using patients with pulmonary arterial hypertension (PAH) as controls.Methods:We analyzed retrospectively the results of AVT in 80 patients with PAH and 175 patients with CTEPH registered in the research database of Beijing Chao-Yang Hospital between October 2005 and August 2014. Demographic variables, cardiopulmonary indicators, and laboratory findings were compared in these two subgroups. A long-term follow-up was conducted in patients with CTEPH. Between-group comparisons were performed using the independent-sample t-test or the rank sum test, within-group comparisons were conducted using the paired t-test or the Wilcoxon signed-rank test, and count data were analyzed using the Chi-squared test. Survival was estimated using the Kaplan-Meier method and log-rank test.Results:The rates of positive response to AVT were similar in the CTEPH (25/175, 14.3%) and PAH (9/80, 11.3%) groups (P > 0.05). Factors significantly associated a positive response to AVT in the CTEPH group were level of N-terminal pro-brain natriuretic peptide (≤1131.000 ng/L), mean pulmonary arterial pressure (mPAP, ≤44.500 mmHg), pulmonary vascular resistance (PVR, ≤846.500 dyn·s−1·m−5), cardiac output (CO, ≥3.475 L/min), and mixed venous oxygen partial pressure (PvO2, ≥35.150 mmHg). Inhalation of iloprost resulted in similar changes in mean blood pressure, mPAP, PVR, systemic vascular resistance, CO, arterial oxygen saturation (SaO2), mixed venous oxygen saturation, partial pressure of oxygen in arterial blood (PaO2), PvO2, and intrapulmonary shunt (Qs/Qt) in the PAH and CTEPH groups (all P > 0.05). The survival time in patients with CTEPH with a negative response to AVT was somewhat shorter than that in AVT-responders although the difference was not statistically significant (χ2 = 3.613, P = 0.057). The survival time of patients with CTEPH who received calcium channel blockers (CCBs) was longer than that in the group with only basic treatment and not shorter than that of patients who receiving targeted drugs or underwent pulmonary endarterectomy (PEA) although there was no significant difference between the four different treatment regimens (χ2 = 3.069, P = 0.381).Conclusions:The rates of positive response to AVT were similar in the CTEPH and PAH groups, and iloprost inhalation induced similar changes in hemodynamics and oxygenation dynamics indices. A positive response to AVT in the CTEPH group was significantly correlated with milder disease and better survival. Patients with CTEPH who cannot undergo PEA or receive targeted therapy but have a positive response to AVT might benefit from CCB treatment.

Albumin May Prevent the Morbidity of Paracentesis-Induced Circulatory Dysfunction in Cirrhosis and Refractory Ascites: A Pilot Study.

Large-volume total paracentesis may result in paracentesis-induced circulatory dysfunction, which is associated with poor outcomes. To explore the short- and long-term effects of paracentesis-induced circulatory dysfunction on systemic hemodynamics, renal function and other cirrhosis-related complications in patients with refractory ascites, following subtotal large-volume paracentesis. Patients with cirrhosis and refractory ascites without renal dysfunction had systemic hemodynamics, renal function, and neurohormones (plasma active renin, aldosterone, norepinephrine and angiotensin II) measured pre- and 6days post-paracentesis. Paracentesis was limited to ≤8L with 6-8g of albumin per liter ascites drained. Patients were followed up until transjugular intrahepatic portosystemic shunt insertion, liver transplantation, or death. Paracentesis-induced circulatory dysfunction was defined as >50% increase in plasma active renin 6days post-paracentesis. Fifty-seven patients (mean age 59.0±9.4years) had mean 6.8±1.8L of ascites removed with 9±3g of albumin given/L of ascites drained. Patients were followed up for 715±104days. Twenty-three patients (40.4%) developed paracentesis-induced circulatory dysfunction with unchanged serum creatinine on day six, despite worsening of hemodynamics (mean arterial pressure 90±10mmHg at baseline vs. 84±8mmHg on day six, p<0.05). Similar hemodynamic changes were observed among patients without paracentesis-induced circulatory dysfunction. There was no significant difference in the long-term renal function or cirrhosis-related complications between the groups. The occurrence of paracentesis-induced circulatory dysfunction, as defined by plasma active renin, may not have a significant short- and long-term impact on renal function or cirrhosis-related complications in patients with refractory ascites who undergo subtotal paracentesis with albumin infusion.

Use of McGrath MAC Videolaryngoscope to Assist Transesophageal Echocardiography Probe Insertion in Intubated Patients.

Transesophageal echocardiography (TEE) probe insertion with the conventional blind insertion technique may be difficult in anesthetized and intubated patients. The use of a videolaryngoscope may facilitate the insertion of the TEE probe. The aim of this study was to compare the conventional technique with the use of the McGrath MAC videolaryngoscope for TEE probe insertion in terms of success rate, duration of insertion, and complications in patients undergoing cardiovascular surgery. A prospective, randomized study. Training and research hospital. Eighty-six adult patients undergoing cardiovascular surgery were included. Eighty-six adult patients were randomized into 2 groups: conventional group (n = 43) and McGrath videolaryngoscope group (n = 43). Success rates, duration of insertion, complications, and hemodynamic changes during insertion were recorded. The success rate of TEE probe insertion at the first attempt was higher in the McGrath videolaryngoscope group (90.5%) than in the conventional group (43.9%) (p = 0.012). The mean duration for successful insertion of the TEE probe at the first attempt was longer in the McGrath videolaryngoscope group (24 s v 11 s) (p = 0.016). The total time for successful insertion of the TEE probe was similar in both groups. Pharyngeal injuries were observed more frequently in the conventional group (17.1% v 2.4%) (p = 0.037). The rate of blood presence on the probe tip in the conventional group was higher than in the McGrath group (21.9% v 4.8%). There were no statistical differences between the 2 groups in systolic blood pressure, mean arterial pressure, diastolic blood pressure, and heart rate before and after TEE insertion. The use of the McGrath MAC videolaryngoscope for TEE insertion in cardiovascular surgery patients increases the success rate and reduces pharyngeal injuries compared to the conventional technique. The use of the McGrath MAC videolaryngoscope for TEE insertion causes similar hemodynamic changes as in the conventional blind insertion technique.

What Are the Hemodynamic and Respiratory Effects of Passive Limb Exercise for Mechanically Ventilated Patients Receiving Low-Dose Vasopressor/Inotropic Support?

Passive limb exercises (PLEs) are used widely in the management of unconscious patients and an early start is recommended. The aim of this study was to determine the effects of PLEs on hemodynamic and respiratory parameters in mechanically ventilated critically ill patients receiving low-dose vasopressor/inotropic support. The charts of 120 mechanically ventilated patients who underwent PLEs were evaluated retrospectively between January 2000 and July 2002. Patients were grouped on the basis of administration of vasopressor/inotropic support. Thirty-eight patients did not get vasopressor/inotropic support (group 1) and 82 patients received low-dose vasopressor/inotropic support (dopamine <10 μg/kg/min, noradrenaline/adrenaline <0.1; group 2). Central venous pressure, heart rate, mean arterial pressure, and oxygen saturation were recorded before and immediately after PLEs. After PLEs in group 1 patients, central venous pressure and mean arterial pressure values increased significantly, and in group 2 patients, central venous pressure increased significantly (P < .05). No statistically significant difference was observed in the rate of change of hemodynamic or respiratory parameters between the 2 groups after the PLEs (P > .05). This retrospective study confirmed that PLEs result in similar hemodynamic and respiratory changes in critically ill patients who received low-dose vasopressor/inotropic support versus those who do not.