Mean Arterial Blood Pressure Measurements Research Articles

Eplerenone Reduces Blood Pressure and Improves Vascular Function in a Mouse Model of Leptin-induced Preeclampsia

Preeclampsia is a hypertensive pregnancy disease that increases the risks for adverse outcomes of pregnancy for both mother and baby, notably by reducing fetal growth in utero. We have shown that mid-late gestation leptin infusion induces preeclampsia characteristics in pregnant mice in inducing hypertension, endothelial dysfunction, and fetal growth restriction, which is ablated in mice with endothelial mineralocorticoid receptor deletion (ECMR). However, there is a lack of preclinical data and rationale for MR antagonism for use in preeclampsia in the existing literature. Therefore, we hypothesized that leptin increases ECMR expression and that MR antagonism decreases hypertension, endothelial dysfunction, and fetal growth restriction in leptin-induced preeclamptic mice. We infused timed-pregnant Balb/C mice with saline (sham) or leptin (LEP, 0.9 mg/kg/day) via s.c. osmotic minipump and administered vehicle or eplerenone (EPL, 200mg/kg/day) in drinking water from gestation day (GD)11-18 (n=7-12). We measured mean arterial blood pressure (BP) via radiotelemetry, vascular function in 2nd order mesenteric arteries by wire myography, and pup/placental weights on GD18. We isolated endothelial cells from placentas of our mice via magnetic cell sorting. Pairwise comparisons were by student’s t test and myography curves analyzed by 2-W ANOVA w/RM. Leptin increased ECMR mRNA expression (3.1±0.32 WT LEP vs 1.1±0.48 WT sham, fold change, *p<0.05) compared to WT sham mice in placenta indicating a direct role for leptin to upregulate ECMR in pregnancy. EPL ablated leptin-induced increases in BP (98±4 LEP/EPL vs 113±3 lep/veh mmHg, *p<0.05), and when treated with EPL leptin did not induce endothelial dysfunction, as assessed as a lack of decrease in vascular relaxation to acetylcholine (p>0.05 LEP/EPL vs sham/EPL). Interestingly, EPL treatment did not prevent leptin from decreasing placental effciency in pregnant mice (7.42±0.17 LEP/veh vs 6.71±0.15 LEP/EPL, pup/placenta weight ratio, p>0.05). Collectively, these data show that leptin infusion from GD11-18 in pregnant mice increases ECMR activation by increasing expression. Furthermore, MR antagonism by eplerenone ablates the maternal hypertension and endothelial dysfunction in leptin-induced preeclampsia mice, however, fetal growth is not restored by eplerenone. Therefore, eplerenone may be a promising therapeutic for the maternal cardiovascular syndrome of preeclampsia patients, however, MR antagonism therapies may need additional agents to improve fetal outcomes. 1R01HL169576, 4R00HL146948. 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.

An Acute Bout of Subconcussive Head Impacts Does Not Change Intracranial Pressure

Purpose: Subconcussive head impacts (SHI) are known to cause a variety of negative sequelae including increased plasma concentrations of neuronal structural and glial proteins, attenuated neurovascular coupling, and impaired vestibular function. Traumatic brain injuries are associated with an increase in intracranial pressure (ICP). However, it is unknown whether an acute bout of SHI increases ICP. We tested the hypothesis that estimates of ICP via ultrasound assessments of optic nerve sheath diameter (ONSD) would be greater following a single session of repetitive SHI versus a control condition. Methods: 14 healthy participants (age: 19±2 y; BMI: 21±4 kg/m2, 3 women) with at least 3 y of soccer heading experience completed two experimental conditions in a randomized crossover design. 20 soccer headings were used to induce repetitive SHI and 20 soccer kicks were used as the control condition. A soccer ball was projected from a soccer JUGS machine (40 km/h, 12.2 m away) every 30 s for both conditions. ONSD assessed via ultrasound is associated with direct measures of ICP. Subjects were in the supine position during ONSD (transverse plane, each eye; B-mode linear array ultrasound), heart rate (HR; 3-lead ECG), and mean arterial blood pressure (MAP; photoplethysmography) measurements conducted at baseline prior to heading/kicking and at 2 h, 24 h, and 72 h post. ONSDs were measured 3 mm under the bulb in triplicate for each eye and the mean values were used for analyses. Inter-eye ONSD values were also averaged for analyses. Clinical intervention to alleviate elevated ICP is indicated when ONSD is > 5.0 mm. Data were analyzed using a mixed-effects model with repeated measures with time and condition as within subject factors. Data are presented as mean ± SD if statistically significant. Results: No subjects had an ONSD > 5.0 mm in either eye following heading or kicking. Left ONSD was greater than baseline at 2 h post heading (2.89 ± 0.25 mm vs. 2.99 ± 0.27 mm; p = 0.0157) and greater than baseline at 2 h (2.92 ± 0.37 mm vs. 2.98 ± 0.31 mm; p = 0.0352) and 72 h (3.08 ± 0.26 mm; p = 0.0067) post kicking. Left ONSD at 72 h post kicking was greater than heading (3.08 ± 0.26 mm vs. 2.93 ± 0.25 mm; p = 0.0022). There were no interaction effects for right ONSD (p = 0.4686), average ONSD (p = 0.1178), HR (p = 0.1039) or MAP (p = 0.3889). Conclusion: Neither the heading nor kicking intervention elicited a clinically relevant ONSD that would require medical attention. Contrary to our hypothesis, an acute bout of 20 soccer headers did not evoke greater ONSD in healthy subjects versus kicking. Therefore, our data indicate that a single session of SHI does not increase ICP. 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.

Three ultrasound guided plane blocks for perioperative analgesia in patients undergoing radical cystectomy: a randomized clinical trial

Background &objective: Transmuscular quadratus lumborum plane block (QLPB), paravertebral plane block (PVPB), and erector spinae plane block (ESPB) are three regional anesthesia techniques for management of perioperative pain for surgical procedures on the trunk, including thorax and abdomen. We compared the effectiveness of PVPB, QLPB type III (QL3), and ESPB for perioperative analgesia during radical cystectomy performed for bladder cancer.
 Methodology: This randomized double-blind trial was performed on 120 patients, aged above 18 years, undergoing radical cystectomy under general anesthesia. Individuals were randomly divided into 3 equal groups: ESPB, PVPB, and QLPB. Blocks were performed under ultrasound guidance preoperatively on each side with 30 ml of 0.25% bupivacaine. Time to perform block and time to the first dose of morphine postoperatively, were noted. Intra-operative hemodynamic data, including MAP and heart rate (HR) were noted every 10 min for an hour, and then at 30 min intervals. Postoperatively, MAP and HR were recorded at 0, 2, 6, 12 and 24 hours. The connection between qualitative factors was investigated using the chi-square test and Fisher's exact test. For the purpose of comparing the groups, one-way ANOVA and the Bonferroni correction were used. A two-tailed P value < 0.05 was considered significant.
 Results: Time to perform block was substantially reduced in ESPB and QL3 groups compared to PVPB group. Time to the first dose of morphine was substantially delayed in the PVPB group than ESPB and QL3 groups. Total 24 h morphine consumption was substantially lower in the PVPB group than ESPB and QL3 groups. Postoperative visual analog scale measurements were substantially lower at 15 min, 30 min, and 12 h in the PVPB group than ESPB and QL3 groups and at 6 h in the ESPB and QL3 groups than in PVPB group. Postoperative mean arterial blood pressure and heart rate measurements were substantially reduced at 0 and 12 h in the PVPB group than in ESPB and QL3 groups and at 6 h in the ESPB and QL3 groups than in PVPB group.
 Conclusions: The ultrasound guided paravertebral plane block was superior to quadratus lumborum plane block type III and erector spinae plane block in providing more effective analgesia but with higher time to perform block.
 Abbreviations: ESPB- Erector Spinae Plane Block; PVPB- Paravertebral Plane Block; QLPB- Quadratus Lumborum Plane Block; QL3- Quadratus Lumborum Plane Block Type III
 Keywords: Paravertebral Plane Block; Quadratus Lumborum Plane Block; Erector Spinae Plane Block; Ultrasound; Radical Cystectomy
 Citation: Seif NE, El-Kholy MM, Ali AR, Zalat MM, Elshazly M. Three ultrasound guided plane blocks for perioperative analgesia in patients undergoing radical cystectomy: a randomized clinical trial. Anaesth. pain intensive care 2024;28(1):85-91; DOI: 10.35975/apic.v28i1.2381
 Received: September 28, 2023; Reviewed: October 31, 2023; Accepted: October 31, 2023

Role of adding dexmedetomidine, ketamine, and magnesium sulphate to caudal block as preemptive analgesia in hypospadias repair in pediatrics: A randomized double-blinded prospective trial

ABSTRACT Background The caudal block (CB) is a quick, and safe approach for pediatric analgesia. Numerous adjuvants were added to extend the analgesia duration. Our trial aims to evaluate the significance of CB by adding dexmedetomidine, ketamine, and MgSO₄ to bupivacaine to provide postoperative analgesia in children undergoing hypospadias repair. Methods This randomized double-blinded study was performed on 75 male children undergoing hypospadias repair under CB. Patients were randomized into three equal groups. All received 0.5 ml/kg bupivacaine 0.25% caudally plus 1 ml volume containing either dexmedetomidine 1 μg/kg in Group D, 0.5 mg/kg ketamine in Group K or 50 mg of MgSO₄ in Group M. Results Time of first rescue analgesia was significantly delayed in group D (8.2 ± 3.45 h) than in group K (5.8 ± 2.85 h) and group M (3.7 ± 1.51 h) (P value = 0.007 vs. <0.001) and in group K than in group M (P value = 0.027). Heart rate and mean arterial blood pressure measurements after block and 60 min intraoperative reduced significantly in group D than in K and Group M. At 6 h and 12 h, FLACC scores were considerably lower with Group D compared to Group K, and Group M, and ketamine group compared to Group M at 4 h. The total amount of pethidine consumed 24 hours postoperatively was significantly lower in Group D than in Group K and Group M. Conclusions Dexmedetomidine as an additive to the CB significantly prolonged time to first analgesia required and decreased total rescue opioid consumption compared to ketamine and MgSO₄.

Initial mean arterial blood pressure (MABP) measurement is a risk factor for mortality in hypertensive COVID-19 positive hospitalized patients.

Hypertension (HTN) is associated with severe COVID-19 infection; however, it remains unknown if the level of blood pressure (BP) predicts mortality. We tested whether the initial BP in the emergency department of hospitalized patients portends mortality in COVID-19 positive(+) patients. Data from COVID-19(+) and negative (-) hospitalized patients at Stony Brook University Hospital from March to July 2020 were included. The initial mean arterial BPs (MABPs) were categorized into tertiles (T) of MABP (65-85 [T1], 86-97 [T2] and ≥98 [T3] mmHg). Differences were evaluated using univariable (t-tests, chi-squared) tests. Multivariable (MV) logistic regression analyses were computed to assess links between MABP and mortality in hypertensive COVID-19 patients. 1549 adults were diagnosed with COVID-19 (+) and 2577 tested negative (-). Mortality of COVID-19(+) was 4.4-fold greater than COVID-19(-) patients. Though HTN prevalance did not differ between COVID-19 groups, the presenting systolic BP, diastolic BP, and MABP were lower in the COVID-19(+) vs (-) cohort. When subjects were categorized into tertiles of MABP, T2 tertile of MABP had the lowest mortality and the T1 tertile of MABP had greatest mortality compared to T2; however, no difference in mortality was noted across tertiles of MABP in COVID-19 (-). MV analysis of COVID-19 (+) subjects exposed death as a risk factor for T1 MABP. Next, the mortality of those with a historic diagnosis of hypertension or normotension were studied. On MV analysis, T1 MABP, gender, age, and first respiratory rate correlated with mortality while lymphocyte count inversely correlated with death in hypertensive COVID-19 (+) patients while neither T1 nor T3 categories of MABP predicted death in non-hypertensives. Low-normal admitting MABP in COVID-19 (+) subjects with a historical diagnosis of HTN is associated with mortality and may assist in identifying those at greatest mortality risk.

Validity and success rate of noninvasive mean arterial blood pressure measurements in cf-LVAD patients: A technical review.

The life expectancy of patients with a continuous flow left ventricular assist device (cf-LVAD) is increasing. Adequate determination and regulation of mean arterial pressure (MAP) is important to prevent adverse events. Given the low pulsatility characteristics in these patients, standard blood pressure equipment is inadequate to monitor MAP and not recommended. We provide an overview of currently available noninvasive techniques, using an extensive search strategy in three online databases (Pubmed, Scopus and Google Scholar) to find validation studies using invasive intra-arterial blood pressure measurement as a reference. Mean differences with the reference values smaller than 5 ± 8 mm Hg were considered acceptable. After deduplication, screening, and exclusion of incorrect sources, eleven studies remained with 3139 successful MAP measurements in 386 patients. Four noninvasive techniques, using Doppler, pulse oximetry, finger cuff volume clamp, or slow upper arm cuff deflation, were identified and evaluated for validity and success rate in cf-LVAD patients. Here, a comprehensive technical background of the blood pressure measurement methods is provided in combination with a clinical use comparison. Of the reported noninvasive techniques, slow cuff devices performed most optimally (mean difference 1.3 ± 5.2 mm Hg). Our results are encouraging and indicate that noninvasive blood pressure monitoring options with acceptable validity and success rate are available. Further technical development and validation is warranted for the growing population of patients on long-term cf-LVAD support.

The Use of Non-Invasive Continuous Blood Pressure Measuring (ClearSight®) during Central Neuraxial Anaesthesia for Caesarean Section—A Retrospective Validation Study

: BackgroundThe close monitoring of blood pressure during a caesarean section performed under central neuraxial anaesthesia should be the standard of safe anaesthesia. As classical oscillometric and invasive blood pressure measuring have intrinsic disadvantages, we investigated a novel, non-invasive technique for continuous blood pressure measuring. Methods: In this monocentric, retrospective data analysis, the reliability of continuous non-invasive blood pressure measuring using ClearSight® (Edwards Lifesciences Corporation) is validated in 31 women undergoing central neuraxial anaesthesia for caesarean section. In addition, patients and professionals evaluated ClearSight® through questioning. Results: 139 measurements from 11 patients were included in the final analysis. Employing Bland–Altman analyses, we identified a bias of −10.8 mmHg for systolic, of −0.45 mmHg for diastolic and of +0.68 mmHg for mean arterial blood pressure measurements. Pooling all paired measurements resulted in a Pearson correlation coefficient of 0.7 for systolic, of 0.67 for diastolic and of 0.75 for mean arterial blood pressure. Compensating the interindividual differences in linear regressions of the paired measurements provided improved correlation coefficients of 0.73 for systolic, of 0.9 for diastolic and of 0.89 for mean arterial blood pressure measurements. Discussion: Diastolic and mean arterial blood pressure are within an acceptable range of deviation from the reference method, according to the Association for the Advancement of Medical Instrumentation (AAMI) in the patient collective under study. Both patients and professionals prefer ClearSight® to oscillometric blood pressure measurement in regard of comfort and handling.

Exposure to Repeated Cold Stress Influences Sympathetic and Cardiovascular Responses to Muscle Stretch in Decerebrated Rats

Chronic stress is known to cause adverse physical and mental effects such as pain, chronic fatigue, and depression, and it is strongly related to many diseases and syndromes (e.g., fibromyalgia, chronic fatigue syndrome, and post‐traumatic stress disorder). Evidence suggests that exercise and physical activity in leisure time are effective in improving stress‐induced symptoms. Repeated cold stress (RCS), in which an animal is repeatedly exposed to alternating room and low temperatures, is one of the chronic stress models that induces chronic pain and depression. Mechanical hyperalgesia through thin muscle afferent fibers has also been reported to occur from RCS exposure. Since the muscle afferents have a dual modulatory function in nociception and cardiovascular reflex, we hypothesized that RCS augments the mechanical component of the exercise pressor reflex (the skeletal muscle mechanoreflex), i.e., skeletal muscle afferents‐mediated increases sympathetic nerve activity (SNA) and arterial blood pressure (AP).[Purpose]The purpose of this study was to clarify the impacts of RCS on sympathetic and cardiovascular responses to stimulation of the skeletal muscle mechanoreflex in decerebrated rats.[Methods]Male Sprague‐Dawley rats (body weight: 410 ± 15 g, age: 12 weeks) were exposed to RCS using a homemade automated RCS device. The rats were alternately moved to room temperature (22°C) and cold temperature (4°C) compartments at 30‐min intervals for 5 days. To assess the skeletal muscle mechanoreflex function, we measured mean AP (MAP), heart rate (HR), and renal SNA (RSNA) responses to 30‐s static passive stretching of the hindlimb muscles by in vivo recording from unanesthetized decerebrated rats. Stretching was performed by tracing the maximum tension curve obtained from 30‐s electrical stimulation. Changes (Δ) from baseline to peak values of the measured parameters between control and RCS rats were compared.[Results]Peak tension during the Achilles tendon stretch from baseline was not significantly different between groups (control: Δ929 ± 63 g [n = 6] vs RCS: Δ765 ± 66 g [n = 4], p = 0.17). Importantly, the peak RSNA response in RCS rats (Δ236.3% and Δ242.7%, n = 2) tended to be greater than that in control rats (Δ37.1% and Δ23.9%, n = 2). Moreover, RCS had a significantly (p &lt; 0.05) greater HR response (RCS: Δ3.7 ± 1.0 bpm [n = 4] vs control: Δ0.6 ± 0.5 bpm [n = 6]), and MAP response tended (P = 0.07) to be higher in the RCS group (Δ23 ± 6 mmHg, n = 4) than in the control group (Δ8 ± 4 mmHg, n = 6).[Conclusions]Our preliminary data demonstrate that RCS augments the skeletal muscle mechanoreflex. These results suggest that chronic stress can potentially cause exaggerated cardiovascular responses during physical activity.

Effects of Fumarate on Blood Pressure and Renal Hemodynamics in Normotensive Rats: Possible Contribution of Sodium Potassium Co‐transporter (NKCC)

The tricarboxylic acid cycle product, fumarate, and its related products, have been implicated in the etiology of genetic and non‐genetic models of hypertension. Fumarate showed a mechanistic link to nitric oxide (NO) production and thus impacted blood pressure and renal hemodynamics in both models. This study evaluated the possibility of a role of fumarate in regulation of blood pressure and renal hemodynamics in normotensive rats and elucidate possible mechanisms involved. Animals were anaesthetized with Thiobutabarbital (100 mg/kg, ip). The carotid artery was cannulated for mean arterial blood pressure (MABP) measurement and the left kidney was exposed to measure cortical blood flow (CBF) and medullary blood flow (MBF). Blood and urine were collected to determine glomerular filtration rate (GFR), urine volume (Uv) and sodium excretion (UNaV). The fumarase inhibitor, pyromellitic acid (PMA) (0.1 mg/kg/h), or fumarate (0.1 mg/kg/h) were infused in these animals. To determine renal sodium excretory mechanisms involved with fumarate, fumarate (1 mg/kg, po) was administered to normotensive rats treated with hydrochlorothiazide (HCTZ) (10 mg/kg, po) or furosemide (10 mg/kg, po), urine was collected hourly for five (5) hours and assayed for sodium. Fumarate elicited a hypotensive effect, with peak effect at the 45th minute (126 ± 6.2 vs 93 ±2.6 mmHg, p&lt;0.05). Similarly, inhibition of fumarase caused a time‐dependent decrease in MABP (p&lt;0.05). There was a consistent drop in CBF in fumarate‐infused rats and although PMA caused an initial rise in CBF at 15 mins, there was a 10‐fold increase in CBF at 60 min when compared to fumarate‐infused rats (p&lt;0.05). MBF also decreased in a time‐dependent fashion in rats infused with fumarate. Consistent with the drop in MABP and CBF, GFR reduced (0.89 ± 0.26 vs 0.39 ± 0.11 mL/min, p&lt;0.05) at 30 mins before to returning to baseline levels at 60 mins in fumarate‐infused rats. Uv was unchanged in rats infused with fumarate but there was a 1‐fold reduction in UNaV at 30 mins (p&lt;0.05). Also, PMA, tended to increase UNaV at 30 mins, compared to baseline. However, there was an exacerbation in UNaV in PMA‐infused rats (24.2 ± 3.8 µmol/L) compared to fumarate‐infused rats at 30 mins (4.56 ±1.4 µmol/L, p&lt;0.05). Fumarate increased UNaV compared to control (p&lt;0.05), however, there was no significant difference in UNaV between furosemide‐treated and furosemide‐treated fumarate rats. These data indicate that fumarate and its products elicited vasodilatory effects that reduced blood pressure and exerted vascular and tubular effects on renal hemodynamics. Also, the tubular effects, possibly involves inhibition of sodium potassium co‐transporter (NKCC).

Cardiac Stroke Volume Index Is Associated With Early Neurological Improvement in Acute Ischemic Stroke Patients.

Early neurological improvement as assessed with the NIH stroke scale (NIHSS) at 24 h has been associated with improved long-term functional outcomes following acute ischemic stroke (AIS). Cardiac dysfunction is often present in AIS, but its association with outcomes is incompletely defined. We performed a pilot study to evaluate the association between non-invasively measured cardiac parameters and 24-h neurological improvement in prospectively enrolled patients with suspected AIS who presented within 12 h of symptom-onset and had an initial systolic blood pressure>140 mm Hg. Patients receiving thrombolytic therapy or mechanical thrombectomy were excluded. Non-invasive pulse contour analysis was used to measure mean arterial blood pressure (MAP), cardiac stroke volume index (cSVI), cardiac output (CO) and cardiac index (CI). Transcranial Doppler recorded mean middle cerebral artery flow velocity (MFV). We defined a decrease of 4 NIHSS points or NIHSS ≤ 1 at 24-h as neurological improvement. Of 75 suspected, 38 had confirmed AIS and did not receive reperfusion therapy. Of these, 7/38 (18.4%) had neurological improvement over 24 h. MAP was greater in those without improvement (108, IQR 96–123 mm Hg) vs. those with (89, IQR 73–104 mm Hg). cSVI, CO, and MFV were similar between those without and with improvement: 37.4 (IQR 30.9–47.7) vs. 44.7 (IQR 42.3–55.3) ml/m2; 5.2 (IQR 4.2–6.6) vs. 5.3 (IQR 4.7–6.7) mL/min; and 39.9 (IQR 32.1–45.7) vs. 34.4 (IQR 27.1–49.2) cm/s, respectively. Multivariate analysis found MAP and cSVI as predictors for improvement (OR 0.93, 95%CI 0.85–0.98 and 1.14, 95%CI 1.03–1.31). In this pilot study, cSVI and MAP were associated with 24-h neurological improvement in AIS.

Intermittent compression of the calf muscle as a countermeasure to protect blood pressure and brain blood flow in upright posture in older adults.

Orthostatic hypotension, leading to cerebral hypoperfusion, can result in postural instability and falls in older adults. We determined the efficacy of a novel, intermittent pneumatic compression system, applying pressure around the lower legs, as a countermeasure against orthostatic stress in older adults. Data were collected from 13 adults (4 male) over 65years of age. Non-invasive ultrasound measured middle cerebral artery blood velocity (MCAv) and finger photoplethysmography measured mean arterial blood pressure (MAP). Intermittent lower leg compression was applied in a peristaltic manner in the local diastolic phase of each cardiac cycle to optimize venous return during 1-min of seated rest and during a sit-to-stand transition to 1-min of quiet standing with compression initiated 15s before transition. During seated rest, compression resulted in a 4.5 ± 6.5mmHg increase in MAP, and 2.3 ± 2.1cm/s increase in MCAv (p < 0.05). MAP and MCAv increased during the 15s of applied compression before the posture transition (2.3 ± 7.2mmHg and 2.1 ± 4.0cm/s, respectively, p < 0.05) with main effects for both variables confirming continued benefit during the transition and quiet stand periods. Application of carefully timed, intermittent compression to the lower legs of older adults increased MAP and MCAv during seated rest and maintained an elevated MAP and MCAv during a transition to standing posture. Future research could assess the benefits of this technology for persons at risk for orthostatic hypotension on standing and while walking in an effort to reduce injurious, unexplained falls in older adults.

Assessment of arterial blood pressure and some biochemical markers of renal function of apparently healthy young adults in Southern Nigeria

Context: Reports on chronic hypertension and its attendant complications in young adults are increasing. Kidney diseases, associated with hypertension, are currently emerging as global public health problem. Despite their significance as the active work force in the country, there is a dearth of data on the blood pressure and renal status of young Nigerian adults.Aim: To measure mean arterial blood pressure and some biochemical indices of renal function of apparently healthy young adults aged between sixteen and thirty-five years, having blood pressure below 140/90 mmHgSettings and design: A total of 650 attendees were randomly selected from five religious congregations across three major cities of Akwa Ibom in Nigeria and used in a cross-sectional study.Material and methods: Arterial blood pressure, serum electrolytes, urea and creatinine of the subjects were determined using standard procedures. Glomerular filtration rate was calculated using the values of serum creatinine.Results: The mean systolic and diastolic blood pressure of tested population were 132.50±4.16 and of 84.36±4.35mmHg respectively. The population mean GFR was 64.56 ±3.28 mL/min/1.73m2, while that of the male and female were 70.50±4.11 mL/min/1.73m2 and 58.20 mL/min/1.73m2 respectively. The values of 144.11±3.34, 5.65± 0.31, 103.04±3.02, 23.81±0.14. 4.74±0.08 and 142.04±3.22 were obtained in mmol/L for sodium, potassium, chloride, bicarbonate, urea and creatinine respectively for males, while the values obtained for females were 141.25±3.58, 4.93±0.11, 101.53± 2.18, 22.18±0.63, 4.02±0.03 and 137.05±4.16 respectively for sodium, potassium, chloride, bicarbonate, urea and creatinine,Conclusion: It was concluded that Nigerian young adults have average arterial blood pressure within the JNC pre-hypertensive range, with mild to moderate derangements in the tested renal function parameters.

Device thrombosis in the Heartware LVAD treatment decision and role of log files

Abstract Background Device thrombosis is a significant problem during durable LVAD support, and device-specific diagnosis and treatment algorithms are necessary to optimize outcomes. The HVAD LVAD has a unique and well-developed logfile capability, yet clinical data on it's use are lacking. Methods and results We reviewed overall outcomes of 322 consecutive patients implanted at our University Medical Center with the HVAD LVAS with a particular emphasis on device thrombosis events. Thirty days, one year, and two years survival was 85.4%,65.0%, and 53.1%, respectively. One hundred eighty-one device thrombosis events occurred in 76 patients. Based on logfile patterns, events were categorized as gradual build-up or sudden build-up or acute occlusion/ingestion (Jorde U JACC-HF 2015). The first thrombosis event was a gradual build-up in 32, sudden build up in 5, and acute occlusion in 11 pts. An additional 46 gradual build-up, two sudden build-up, nine acute occlusion events occurred as recurrent events. 2-year survival without CVA was 72.8% in patients with gradual onset device thrombosis 72 pts received TPA. TPA was given, after discontinuing anticoagulation, and taking the INR level is under 2.0 and keeping invasively measured mean arterial blood pressure between 65–80 mmHg low dose tenecteplase (1000 units) was then given, and if clinical and logfile improvement did not occur repeated every six hours up to a total fo 4 doses (4000 units) over 24 hours. Successful therapy was defined as clinical resolution of pump thrombosis without recurrence in 30 days, LDH improvement and power consumption returned to normal, and occurred in 74.4% gradual onset, 71.4% sudden onset, and 56.3% acute occlusion. TPA was complicated by severe hemorrhage or death in 6.4% of patienst with a gradual build-up pattern, 14.3% with sudden build-up, and in 33.3% with acute occlusion. Conclusion Device thrombosis frequently occurs in HVAD patients, and response to therapy can be predicted by logfile analysis. TPA is an excellent option for gradual onset device thrombosis but should be avoided in the setting of acute occlusions, where early device exchange may be a better first-line strategy. Refinement of logfile analysis including earlier thrombus detection and incorporation of these techniques into clinical practice may significantly improve outcomes with the HVAD LVAD. Funding Acknowledgement Type of funding source: None

Cardiovascular changes in genetic absence epileptic WAG/Rij rats: Effects of chronic ethosuximide treatment

Purpose: The aim of this study was to investigate the effects of chronic ethosuximide (ETX) treatment on absence seizures and cardiovascular parameters in WAG/Rij rats with genetic absence epilepsy.Materials and Methods: Eight-weeks old, male Wistar and WAG/Rij rats were divided into four groups (n=20): Wistar control, Wistar ETX, WAG/Rij control and WAG/Rij ETX. ETX groups received chronic ETX treatment (oral, 300 mg/kg/day) for 3 months. At the end of the 3-month-treatment period; the total and mean duration, also number of spike wave discharges (SWDs) were evaluated using EEG recordings. Mean arterial blood pressure (MAP) and heart rate (HR) measurements were performed. Results: ETX treatment significantly decreased the duration and frequency of SWDs in WAG/Rij rats. MAP in WAG/Rij control group was markedly higher than Wistar control group. In Wistar ETX group, HR was significantly slower than Wistar control group. KCl-induced contraction response enhanced in Wistar ETX group and diminished in WAG/Rij control group compared to Wistar control group. Conclusion: Increased MAP and vascular reactivity in WAG/Rij rats. ETX treatment did not alter cardiovascular parameters in WAG/Rij rats whereas the treatment decreased the HR and vascular reactivity without affecting MAP in Wistar rats. T-type Ca++ channels may play a role in these changes.

Effects of Norepinephrine on the Intestinal Vascular System in Rabbits With Endotoxic Shock.

We hypothesized that jejunal mucosal tissue blood flow would decrease following norepinephrine (NE) administration in endotoxic shock. We aimed of this study to evaluate changes in superior mesenteric venous (SMV) blood flow and jejunal mucosal tissue blood flow of the intestinal vascular system over time by administration of NE in rabbits with endotoxic shock. We created four groups (n = 8 each): control group, lipopolysaccharide (LPS; 1 mg/kg) group, NE (2 μg/kg/min) group, and LPS+NE group. As indicators of circulation, we measured mean arterial blood pressure (MAP), cardiac output, SMV blood flow, and jejunal mucosal tissue blood flow every 30 min from 0 to 240 min. The drop in MAP observed in the LPS group was suppressed by NE administration. SMV blood flow dropped temporarily with LPS administration, but then rose thereafter. Administration of NE to the LPS group suppressed the transient decline in SMV blood flow, which did not drop below that of the control group. In the LPS group, jejunal mucosal tissue blood flow transiently dropped and then rose, reflecting the pattern in SMV blood flow. In the LPS+NE group, however, although there was no drop in SMV blood flow, jejunal mucosal tissue blood flow remained low. An interaction between NE and LPS was observed regarding jejunal mucosal tissue blood flow from 90 to 180 min (P = 0.033). We showed that NE maintained MAP and SMV blood flow but decreased jejunal mucosal tissue blood flow. In a rabbit model of endotoxic shock, NE had a negative effect on jejunal mucosal tissue blood flow.

Effects of awake caudal anesthesia on mean arterial blood pressure in very low birthweight infants

BackgroundIntraoperative blood pressure is a relevant variable for postoperative outcome in infants undergoing surgical procedures. It is therefore important to know whether the type of anesthesia has an impact on intraoperative blood pressure management in very low birth weight infants. Here, we retrospectively analyzed intraoperative blood pressure in very low birthweight infants receiving either awake caudal anesthesia without sedation, or caudal block in combination with general anesthesia, both for open inguinal hernia repair.MethodsEthical approval was provided by the University of Tuebingen Ethical Committee on 05/29/2018 with the project number 403/2018BO2. Patient records of infants admitted by the neonatologist (median age at birth 31.1 ± 3.5 weeks, median weight at birth 1240 ± 521 g) which were scheduled for inguinal hernia repair were retrospectively evaluated for the course of mean arterial blood pressure and perioperative interventions to stabilize blood pressure. A total of 42 patients were included, 16 patients (11 boys, 5 girls) received awake caudal anesthesia, 26 patients (22 boys, 4 girls) a combination of general anesthesia and caudal block.ResultsApproximately 3% of the measured mean arterial blood pressure values in the caudal anesthesia group were below a critical margin of 35 mmHg, in contrast to 47% in the combined anesthesia group (p < 0.001). Patients in the latter group showed a significantly larger drop of mean arterial blood pressure below 35 mmHg (4.7 ± 2.7 mmHg vs. 1.9 ± 1.6 mmHg; p < 0.005) and a significantly longer time of mean arterial blood pressure below 35 mmHg (25.6 ± 26.0 min vs. 0.9 ± 2.3 min; p < 0.001), although they received more volume and vasopressor boluses for stabilization (27 ± 14.8 ml vs. 10 ± 4.1 ml; p < 0.01 and 0.15 ± 0.06 ml vs. 0 ml of cafedrine/theoadrenaline; p < 0.001).ConclusionsThe study indicates that the use of caudal block as stand alone procedure for inguinal hernia repair in very low birthweight infants might be advantageous in preventing critical blood pressure drops compared to a combination of caudal block with general anesthesia.

High-Flow Nasal Cannula Oxygen in Patients Having Anesthesia for Advanced Esophagogastroduodenoscopy: HIFLOW-ENDO, a Randomized Clinical Trial.

Over 6 million esophagogastroduodenoscopy (EGD) procedures are performed in the United States each year. Patients having anesthesia for advanced EGD procedures, such as interventional procedures, are at high risk for hypoxemia. Our primary study aim was to evaluate whether high-flow nasal cannula (HFNC) oxygen reduces the incidence of hypoxemia during anesthesia for advanced EGD. Secondarily, we studied whether HFNC oxygen reduces hypercarbia or hypotension. After obtaining written informed consent, adults having anesthesia for advanced EGD, expected to last longer than 15 minutes, were randomly assigned to receive HFNC oxygen or standard nasal cannula (SNC) oxygen. The primary outcome was occurrence of one or more hypoxemia events during anesthesia, defined by arterial oxygen saturation <92% for at least 15 consecutive seconds. Secondary outcomes were occurrence of one or more hypercarbia or hypotension events. A hypercarbia event was defined by a transcutaneous CO2 measurement 20 mm Hg or more above baseline, and a hypotension event was defined by a mean arterial blood pressure measurement 25% or more below baseline. Two hundred seventy-one adult patients were enrolled and randomized, and 262 patients completed study procedures. Eight randomized patients did not complete study procedures due to changes in their anesthesia or endoscopy plan. One patient was excluded from analysis because their procedure was aborted after 1 minute. Patients who received HFNC oxygen (N = 132) had a significantly lower incidence of hypoxemia than those who received SNC oxygen (N = 130; 21.2% vs 33.1%; hazard ratio [HR] = 0.59 [95% confidence interval {CI}, 0.36-0.95]; P = .03). There was no difference in the incidence of hypercarbia or hypotension between the groups. The HR for hypercarbia with HFNC oxygen was 1.29 (95% CI, 0.89-1.88; P = .17), and the HR for hypotension was 1.25 (95% CI, 0.86-1.82; P = .25). HFNC oxygen reduces the incidence of hypoxemia during anesthesia for advanced EGD and may offer an opportunity to enhance patient safety during these procedures.

Initial blood pressure is important for long-term outcome after traumatic spinal cord injury.

Patients with traumatic spinal cord injury (TSCI) are at risk of developing neurogenic shock that causes hypotension and thereby secondary injury to the spinal cord due to ischemia. Hemodynamic treatment of patients with acute TSCI remains inadequately elucidated. Guidelines for management are divergent and based on limited evidence. To this end, the authors evaluated whether mean arterial blood pressure (MABP) during the prehospital and initial hospital phases of TSCI treatment is correlated with long-term neurological outcome. The authors performed a retrospective cohort study based on a chart review of MABP data collected during the prehospital transport, in the operating room (OR), and in the neurointensive care unit (NICU) during the first 7 days after trauma. Data from the NICU were divided into two periods: days 1-2 and days 3-7. Data were analyzed using Spearman's rank correlation to evaluate for any correlation between MABP and changes in the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) score 1 year postinjury. In the analysis, the MABP target value was 80 mm Hg. Hypotension was treated with metaoxedrin or norepinephrine. Statistically significant differences were evaluated using Spearman's rank correlation coefficient. The chart review yielded 129 patients treated for TSCI. The inclusion period was 2010-2017. For the prehospital transport measurements of MABP, the Spearman's rank correlation coefficient was a rho of 0.5662 (p < 0.001), for OR measurements it was a rho of 0.6818 (p < 0.001), and for the NICU measurements it was a rho of 0.4611 (p < 0.001); for NICU unit days 1-2 and days 3-7, the Spearman's rank correlation coefficient was a rho of 0.2209 (p = 0.0681). Continuous MABP levels exceeding 80 mm Hg have a significant impact on neurological outcome-from earliest possible stabilization in the prehospital care, through hospital admission, the surgical phase, and into the first 2 days in the NICU.

Blood pressure extremes and severe IVH in preterm infants.

BackgroundThe optimal upper and lower limits of blood pressure in preterm infants are not known. Exceeding these thresholds may contribute to intraventricular hemorrhage (IVH).MethodsPreterm infants born ≤30 weeks GA were identified. Infants had continuous measurement of mean arterial blood pressure (MABP) for 7d and cranial ultrasound imaging. IVH was classified as severe IVH (grade 3/4), no severe IVH (no IVH; grade 1/2), or no IVH.Mean±SEM MABP values from hours 1–168 were calculated and sorted into bins 2 mmHg wide. The normalized proportion of each recording spent in each bin was then calculated. Candidate limits were identified by comparison of MABP distribution in those with severe IVH vs. those without severe IVH.Results85 million measurements were made from 157 infants. Mean EGA was 25.2 weeks; mean BW was 749g; 65/157 female; inotrope use in 59/157; grade 3/4 IVH in 29/157. Infants with severe IVH spent significantly more time with extreme MABP measurements (<23 mmHg or >46mmHg) compared to those without severe IVH (12% vs. 8% of recording, p=0.02).ConclusionInfants who developed severe IVH had substantially more unstable MABP and spent a significantly greater period of time with MABP outside of the optimal range.

Cerebrovascular autoregulation in preterm fetal growth restricted neonates

ObjectiveTo investigate the effect of fetal growth restriction (FGR) on cerebrovascular autoregulation in preterm neonates during the first 3 days of life.DesignCase–control study.SettingNeonatal intensive care unit of the Wilhelmina Children’s...