Fall In Blood Pressure Research Articles

Risk Factors and Clinical Outcomes of Perioperative Hypotension in the Neck of Femur Fracture Surgery: A Case-Control and Cohort Analysis.

Introduction Neck-of-femur (NOF) fractures have high prevalence rates and require prompt surgical intervention for better outcomes. Perioperative hypotension (POH) in the geriatric population has poor outcomes with several contributing factors. The study intends to explore these risk factors and their correlation with patient outcomes. Methodology We studied a total of 276 patients who underwent surgical fixation of the NOF fracture at St Peter's Hospital, Surrey, from June 1, 2022, to June 1, 2023. Patients with POH were identified; the risk factors and one-year outcome were studied to obtain the results. We used odds ratio (OR), relative risk (RR), and multivariate regression to analyse the statistical association within the data. Results The incidence of POH was 68% (188/276) which included preoperative hypotension (9.78%), intraoperative hypotension (48.55%), and postoperative hypotension with a mean arterial pressure (MAP) of <65 mmHg (24.63%) and fall of systolic blood pressure to less than 80% (34.42%). Statistically significant risk factors were hypertension (OR: 1.330), heart disease (OR: 2.768), and hemoglobin (Hg) drop (OR: 1.42). The outcomes we studied were all statistically significant, with an RR of more than one. It includes postoperative delirium (RR: 2.037), postoperative 30-day morbidity (RR: 4.008), postoperative 30-day mortality (RR: 6.12), 365-day mortality (RR: 2.224), postoperative delay in mobilisation (RR: 1.329), and prolonged length of stay (RR: 1.273). Conclusion The study shows a clear association between POH and increased postoperative complications, highlighting the need for prompt intervention. This case-control study identified hypertension, history of heart disease, and perioperative blood loss as significant risk factors for developing POH. Also, this study demonstrates that POH is significantly associated with adverse outcomes, including the increased risk of delirium, prolonged hospital stays, and elevated 30-day morbidity in elderly patients undergoing hip fracture surgery.The findings also indicated that the duration of hypotension did not directly influence the outcomes; its occurrence alone is a significant factor in developing these complications.

Blood Pressure Regulation in Post-COVID POTS: Beyond Sinus Tachycardia.

Postural orthostatic tachycardia syndrome (POTS) is a frequently diagnosed cardiovascular disorder after COVID-19 infection. POTS is characterized by the presence of excessive sinus tachycardia on standing without a fall in blood pressure (BP). We investigated the BP profile using 24-hour ambulatory BP monitoring in patients with new-onset POTS after COVID-19 compared with prepandemic population-based controls. We performed a case-control study in 100 patients (mean age, 40.0±12.9 years; 85% women) with verified post-COVID-19 new-onset POTS diagnosed by a positive head-up tilt testing versus 100 controls from a population-based cohort with a negative active standing test, no history of syncope, POTS, or endocrine disease (mean age, 42.3±14.0 years; 78% women). Twenty-four-hour BP profile was assessed for circadian BP variation including hypotensive systolic BP (SBP) episodes (<80, <90, and <100 mm Hg). Patients with post-COVID-19 POTS had significantly higher nighttime SBP, but not daytime SBP, and more daytime SBP hypotensive episodes compared with controls. Nondipping (34% versus 19%; P<0.001) and reverse dipping patterns (9% versus 0%; P<0.001) were more frequent in post-COVID-19 POTS. In the logistic regression, patients with post-COVID-19 POTS had significantly higher mean 24-hour SBP (odds ratio, 1.08 [95% CI, 1.04-1.11]; P<0.001) and nighttime SBP (odds ratio, 1.07 [95% CI, 1.04-1.10]; P<0.001), independent of age and sex. Patients with post-COVID-19 POTS demonstrate higher mean 24-hour and nighttime SBP and show disruptions of circadian BP rhythm regulation compared with population-based controls, as well as more daytime hypotensive episodes. Future studies are needed to test whether patients with post-COVID-19 POTS may benefit from tailored BP therapy.

A Comparative Study of Infusion of Ephedrine and Phenylephrine on Hemodynamic Stability After Spinal Anesthesia in Elderly Patients Undergoing Lower Limb Orthopedic Surgeries.

Background Hypotension during spinal anesthesia occurs due to sympathetic nervous system blockade, resulting in decreased systemic vascular resistance and reduced cardiac output. Due to reduced sympathetic tone, peripheral arterial vasodilatation and blood pooling in lower limbs due to venodilatation occur, reducing preload to the heart and stroke volume. The elderly patients have reduced cardiovascular compensatory mechanisms, increasing the frequency and severity of hypotension due to sympathetic blockade after spinal anesthesia significantly. Vasopressors correct hypotension during the intraoperative period to maintain organ perfusion. Fluids can be administered, and if given excessively, can cause fluid overload and urinary retention. This study aimed to compare the effectiveness of vasopressors, phenylephrine, and ephedrine in maintaining hemodynamic stability intraoperatively through prophylactic infusion after spinal anesthesia in elderly patients for lower limb orthopedic surgeries. Methodology A total of 174 elderly patients aged 60 years and above with American Society of Anesthesiologists (ASA) Classification I and II, undergoing lower limb orthopedic surgeries, enrolled in a randomized comparative study, were allocated into three groups: Group P (phenylephrine, n=58) received 250 mcg phenylephrine in 30 ml normal saline using infusion syringe pump, Group E (ephedrine, n=58) received 30 mg ephedrine in 30 ml normal saline using infusion syringe pump, and Group C (control group, n=58) received mephentermine I/V (6 mg bolus) when the fall in blood pressure was below 30% of baseline without any placebo infusion. Hemodynamic parameters (systolic and diastolic blood pressure, mean arterial pressure (MAP), heart rate) at 15, 10, and 5-minute intervals before spinal anesthesia, and at 3, 6, 9, 12, 15, 20, 25, and 30-minute intervals after spinal anesthesia. The need for rescue doses to treat hypotension after spinal anesthesia was recorded. Result At all time intervals following spinal anesthesia, Group E reported heart rate and systolic blood pressure better than Groups P and C, significantly. At 3, 6, 9, 12, 15, and 25-minute intervals following spinal anesthesia, the diastolic blood pressure in Group E was enhanced significantlythan Groups P and C. The MAP in Group E was substantially higher than in other groups at 3, 6, 15, and 20-minute intervals following spinal anesthesia, which was statistically significant. Compared to Groups P and C, Group E required lesser rescue doses to treat intraoperative fall in hypotension 30% below baseline and lesser events of bradycardia. Conclusion Following spinal anesthesia, the preload to the heart is to be maintained with intravenous (crystalloid or colloidal) solutions to maintain cardiac output adequately. Intraoperative use of phenylephrine and ephedrine as a low-dose prophylactic infusion can be used, as it increases both systemic vascular resistance and preload without cardiac stimulation along with intravenous solutions to maintain hemodynamic parameters such as systolic and diastolic blood pressure, MAP, heart rate effectively but preferably ephedrine in elderly patients.

Postural Orthostatic Tachycardia Syndrome (POTS) as a Cause of Dizziness - Expanding the Etiological Spectrum.

Dizziness is a frequent complaint encountered in neurology clinics. Dizziness can be spontaneous or triggered, which includes orthostatic dizziness. Orthostatic dizziness can be acute (reflex/vasovagal syncope), chronic (orthostatic hypotension (OH), or postural orthostatic tachycardia syndrome (POTS). Since dizziness has numerous causes, these patients undergo extensive investigations before a diagnosis is made. Here, we describe five patients who presented with dizziness and were diagnosed to have POTS on evaluation. We conducted a retrospective study of patients who presented to the Department of Neurology from August 2020 to November 2021 with the complaint of dizziness and were diagnosed with POTS. The clinical history, neurological examination, treatment response, routine blood investigations, magnetic resonance imaging (MRI) brain, and autonomic function tests (AFTs) of the patients were reviewed from patients' clinical records. Patients with dizziness and with diagnosis other than POTS were excluded from the study. Among the five patients, males were predominant with a male to female ratio of 3:2. All the patients were in their early fourth decade with a mean age of 35.4 years. The presenting symptom was dizziness, and the key associated symptoms were anxiety and headache. Due to the orthostatic nature of symptoms and absence of orthostatic fall in blood pressure (BP), a detailed AFT was carried out, leading to the diagnosis of POTS. Patients were assessed at 3-6 months after treatment and there was a moderate response in one and no response in the remaining four patients. POTS should be considered a possible etiology when patients present with orthostatic dizziness in the absence of orthostatic fall in BP. Anxiety and headache may be associated with this type of dizziness.

Effect of endothelin-1 on the blood pressure response to acute hypoxia and hyperoxia in healthy young men.

Endothelin-1 (ET-1) and its receptors are linked to increases in sensitivity of the chemoreceptors to hypoxic stress and the development of hypertension in preclinical models. We hypothesized ET receptor antagonism would lower resting blood pressure (BP) as well as the acute BP response to chemoreflex stress. Twenty-four men (31 ± 5 years, 26 ± 3 kg/m2) completed two study visits (control, bosentan). On each visit, BP was assessed under three conditions: (1) normoxia (FiO2 0.21), (2) chemoreflex excitation via hypoxia (FiO2 0.05-0.21), (3) chemoreflex inhibition via hyperoxia (FiO2 1.00). Bosentan increased plasma ET-1 (0.94 ± 0.90 to 1.27 ± 0.62 pg/mL, p = 0.004), supporting receptor blockade. Resting diastolic (73 ± 5 to 69 ± 7 mmHg, p = 0.007) and mean (93 ± 7 to 88 ± 7 mmHg, p = 0.005) BP were reduced following bosentan compared to control with no change in systolic BP (p = 0.507). The mean BP response to both acute hypoxia (-0.48 ± 0.38 to -0.25 ± 0.31 mmHg/%, p = 0.004) and hyperoxia (area under the curve -93 ± 108 to -27 ± 66 AU, p = 0.018) were attenuated following bosentan. Acute ET receptor inhibition attenuates the rise in BP during chemoreflex excitation as well as the fall in BP during chemoreflex inhibition in healthy young men. These data support a role for ET-1 in control of resting BP, possibly through a chemoreceptor-mediated mechanism.

Perioperative infusion of magnesium sulfate versus dexmedetomidine on the hemodynamic responses in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial

Background: Laparoscopic cholecystectomy is associated with less post-operative pain, shorter hospitalization, and a faster functional recovery as compared to the open procedure. However, like any other surgery, a stress response is induced. Anesthesia interventions such as direct laryngoscopy, tracheal intubation, and extubation involve severe sympathetic stimulation. Magnesium can block the release of catecholamines from both the adrenal gland and adrenergic nerve terminals by inhibiting of activation of membrane Ca²⁺-ATPase and Na⁺-K⁺-ATPase. Aims and Objectives: Both magnesium sulfate and dexmedetomidine decrease the release of catecholamines and attenuate pressor responses to anesthesia and surgery. Materials and Methods: Eighty-four ASA I/II patients were randomly allocated to two groups. Group D received dexmedetomidine 1 μg/kg followed by 0.4 μg/kg/h and Group M received 2 g MgSO₄ followed by 15 mg/kg/h. hemodynamic variables were recorded as T0 (after loading dose of study drug), just before (T1) and 1, 2, and 3 min after ProSeal laryngeal mask airway (PLMA) insertion (T2 [i] [ii] [iii]), before and after peritoneal insufflation (T3 and T4), before and after table tilt (T5 and T6), after resuming flat position (T7), peritoneal deflation (T8), PLMA removal (T9), and on post-anesthesia care unit admission (T10). Data were collected and analyzed using SPSS 17 statistical software. Results: The demographic profile was comparable. After the study drug administration, there was a fall in mean arterial pressure (MAP) in both groups (Group D &gt; Group M) and no pressor response to PLMA insertion. At peritoneal insufflation, the MAP increase was significantly more in Group M at T6, T7, and T8 (31.9%, 27.9%, and 35.6% above baseline, respectively). Although there was a fall in systolic blood pressure (SBP) from the baseline throughout the procedure in both groups, SBP was significantly higher at most times in Group M as compared to Group D (P&lt;0.05). In both groups, there was a similar rise in diastolic blood pressure after peritoneal insufflation. The mean heart rate was significantly lower in Group D at all time points. Conclusion: Dexmedetomidine seemed to be superior to MgSO₄ for ameliorating hemodynamic responses in patients undergoing laparoscopic cholecystectomy.

Hemodynamic Effects of Bone Cement Implantation in Hip Arthroplasty: Insights from a Prospective Study in Eastern India.

Bone cementation has various effects on hemodynamics including potentially fatal bone cement implantation syndrome (BCIS). Most of the studies on BCIS are from developed countries. We have studied the effect of bone cement on hemodynamics in hip arthroplasty in the eastern Indian population and compared it with the available literature. This prospective study was done by a team of orthopedic surgeons and anesthesiologists in a tertiary center in eastern India between March 2020 and December 2022. Seventy-two patients (Male 38: and Female 34) of age between 25 and 100 years fulfilling the inclusion criteria were included. In 43 patients (43/72, 59.72%) systolic and diastolic blood pressure fell in the range of 10 mmHg, in 22 patients (22/72, 30.56%) fall in blood pressure was in the range of 10-20 mmHg, and more than 20 mmHg fall in blood pressure were seen in seven patients (7/72, 9.72%). SPO2 decreased from 97-100% to 94-96% in 28 patients and 90-93% in six patients, which began to rise after 5 min of cementing and returned to normal after 10 min. Arrhythmias were seen in 16 patients with multiple comorbidity. Two patients had a cardiac arrest and one patient died after 6 h in the intensive care unit. Pre-operative evaluation, perioperative monitoring of hemodynamic parameters during cementing especially in high-risk patients with multiple comorbidities, and taking essential precautions during cemented arthroplasty are the key to preventing complications like BCIS.

Learning implementation of a guideline based decision support system to improve hypertension treatment in primary care in China: pragmatic cluster randomised controlled trial

ObjectiveTo evaluate the effectiveness of a clinical decision support system (CDSS) in improving the use of guideline accordant antihypertensive treatment in primary care settings in China.DesignPragmatic, open label, cluster randomised...

Cardiovascular Autonomic Modulation in Chronic Coronary Syndrome Following Percutaneous Coronary Intervention.

Introduction The risk of sudden death in patients with chronic coronary syndrome (CCS) is increased by unbalanced cardiovascular autonomic function. Since myocardial ischemia appears to be the causeof this condition of autonomic dysregulation, treating this condition should improve and correct the autonomic functions. Improving myocardial perfusion by PCI might have beneficial effects on the recovery of autonomic balance in ischemia-triggered autonomic dysregulation. Objective In the present study, autonomic modulation in patients with CCS was evaluated before and after percutaneous coronary intervention (PCI) using cardiovascular reflex tests. Methods A total of 30CCS patients were recruited from the cardiology outpatient department. The patients were tested withcardiovascular reflex tests (lying to standing, 30:15 ratio, Valsalva ratio, isometric handgrip test, and deep breathing test) before and after PCI. The licensed statistical software SPSS version 21.0 was used to compile and analyse the data. Results Out of 30 patients, parasympathetic reactivity tests conducted post-PCI were significantly higher as compared to pre-PCI patients: (1) lying to standing - 30:15 ratio (1.17± 0.102 versus 1.03± 0.064, p=0.000); (2) Valsalva ratio (1.42±0.276 versus 1.02±0.133, p=0.000), (3) delta heart rate in deep breathing test (17.23± 3.004 bpm versus 7.85± 4.076 bpm, p=0.000), and (4) expiration to inspiration (E:I) ratio (1.25± 0.050 versus 1.11± 0.064, p=0.000. Among sympathetic reactivity tests, lying to standing test for fall in systolic blood pressure was significantly higher in the pre-PCI state than post-PCI (-20.73± 10.29 versus -2.33± 7.67, p=0.000). The rise in DBP of the isometric handgrip test was significantly higher in post-PCI compared to pre-PCI patients (36.73±8.39 mm Hg versus 16.63±8.47 mm Hg, p=0.000). Conclusion Resting autonomic tone as determined by cardiovascular reflex testing reveals an increase in both parasympathetic and sympathetic reactivity following PCI in CCS, according to the findings of this preliminary study. As a result, we propose that noninvasive procedures like cardiovascular reflex tests be used to stratify the likelihood of illness development in the future.

Cardio-Ankle Vascular Index and left ventricular mass as markers of nocturnal blood pressure fall in the general population.

Findings regarding the association between Cardio-Ankle Vascular Index (CAVI) and the extent of nocturnal blood pressure (BP) fall in the general population are scanty. We sought to investigate this issue in the participants enrolled in the Pressioni Monitorate E Loro Associazioni (PAMELA) study. The study included 491 participants who attended the second and third surveys of the PAMELA study performed after 10 and 25years from the initial evaluation. Data collection included medical history, anthropometric parameters, office, home, ambulatory blood pressure BP monitoring (ABPM), blood examinations, echocardiography, and CAVI measurements. In the whole study, both CAVI and left ventricular mass index (LVMI) were inversely correlated with nocturnal SBP fall, expressed as day-night percent change (r = - 0.152, p = 0.0007, and r = - 0.213, p < 0.0001, respectively). However, after adjustment for sex and age, the correlation remained significant only for LVMI (r = - 0.124, p = 0.006). Non-dipper participants exhibited significantly higher sex-age adjusted LVMI (91 ± 22 vs 82 ± 18g/m2 (p < 0.0001)), but not of CAVI (9.07 ± 2.0 and 9.57 ± 2.2m/s, p = ns). Similar results were found when classifying participants into quartiles of nocturnal SBP drop. Finally, both sex-age adjusted CAVI and LVMI were positively correlated with mean nocturnal SBP (r = 0.181, p < 0.001, and r = 0.240, p < 0.0001). Although arterial stiffness assessed by CAVI, unlike LVMI, is unrelated with the degree of nocturnal BP drop, this marker is useful in identifying nocturnal hypertension and optimizing cardiovascular risk stratification in the community.

Effects of General Anesthesia on Noninvasively Measured Central and Peripheral Blood Pressure: A Prospective, Observational-based Cross-over Study

Abstract Background: Blood pressure (BP) monitoring is the basic hemodynamic parameter necessary to monitor the hemodynamic changes occurring under general anesthesia (GA) to maintain adequate perfusion to major organs such as the heart, brain, and kidneys. Physicians heavily rely upon peripheral hemodynamic measurements despite availability of devices suitable for measurement of central blood pressure through non-invasive manner paving a gap in the literature concerning the effects of GA on central pressure. Aims and Objective: In this comparative cross-over study, authors have aimed to find out the degree of changes in central and peripheral BP after the introduction of GA among adult patients of different age groups scheduled for routine surgical procedures with an objective to maintain vital functions more precisely – considering the fact that vital organ perfusions (heart, brain etc.,) depend more on the required values of CBP than that of PBP. Material &amp; Methods: Following approval from IEC, sixty adult patients with ASA physical status 1 or 2 undergoing routine surgical procedures under general anesthesia were enrolled in this prospective cross-over study where each patient was case as well control for measurement and comparison of his/her central and peripheral blood pressure. Patients, being divided into three groups as per age range - 20-40 years (Group A), 40-60 years (Group B), and 60-80 years (Group C) had their normal Riva Rocci BP cuff (Space Lab Inc. USA) placed in one arm for peripheral BP measurement and special Riva Rocci (Uscom Ltd., Australia).) BP cuff for on another arm for Central BP measurement. After patient’s arrival into operation theatre, baseline hemodynamic parameters were taken followed by sequential measurements of CBP and PBP with an interval of 2 minutes till 30-40 mins of operation. There were alternative measurements of these pressures with recording of data from either of the devices as mentioned for further comparison and analysis. Results: From baseline values, it was found that all the three groups were comparable in respect of age, height, weight, PBP and CBP. When measured pressure of all groups combined, that there was a fall in both Central and Peripheral SBP as well as DBP after giving intravenous induction agent (propofol) and rise in both central and peripheral SBP and DBP after laryngoscopy and intubation. Degree of systolic blood pressure change in both peripheral &amp; central that is fall of BP in 3rd reading &amp; rise of BP in 5th reading was greatest in group C, followed by group B, then group A [p - 0.005]. While comparing three subgroups, the baseline Augmentation Index (AI) was highest in group C and lowest in group A. Following the administration of general anesthesia (GA), the change in Augmentation Index (ΔAI), was most pronounced in the third reading corresponding to the time after the administration of the induction agent. Conclusion: Measurement of CBP through peripheral placement of cuff is a unique feasible method to detect real changes of circulation with actual pressure in vital organs. Thus, the study suggests that central blood pressure measurements can provide a more accurate reflection of hemodynamic changes during general anesthesia, especially in older individuals or those with different cardiovascular conditions allowing better vital management of body circulation.

Heated environment increases blood pressure drop and postural sway during initial orthostasis in healthy subjects.

We tested the hypothesis that heat stress influences the closed-loop cardio-postural control by an increased blood pressure (BP) drop and postural sway. Fourteen healthy individuals (eight women) performed two orthostatic tests under thermal reference (TC; ~ 24ºC) and HOT (~ 38ºC) conditions. The center-of-pressure (COP) displacements and the electromyography (EMG) activity of the calf muscles (medial gastrocnemius and tibialis anterior) were recorded during the initial orthostasis (ORT onset) after the supine-to-stand challenge. At the same period, BP (beat-to-beat) was continuously monitored, and supine-to-stand variations (∆%) were calculated. Sublingual temperature (Tsl) was measured as a surrogate of internal temperature. Tsl increased in HOT compared to TC (TC 36.5 ± 0.3 vs. HOT 36.7 ± 0.3ºC; p < 0.01). COP distance was greater in HOT compared to TC condition (TC 596.6 ± 242.4 vs. HOT 680.2 ± 249.1mm; p < 0.01). EMG activity of the gastrocnemius decreased in HOT compared to TC condition (TC 95.5 ± 19.8 vs. HOT 78.4 ± 22.8%mV; p = 0.02). EMG of tibialis did not change between TC and HOT (TC 83.5 ± 42.9 vs. HOT 66.1 ± 31.9%mV; p = 0.29). BP showed a greater fall in HOT compared to TC condition (∆%TC -24.5 ± 13.2 vs. ∆%HOT -33.2 ± 20.2%; p = 0.01). Heat stress causes a greater fall in blood pressure and a reduction in musculoskeletal pump activity during orthostatic onset. These effects could be potential mechanisms that underlie augmented postural instability under a heated environment.

The time-course augmentation of perivascular space enlargement in the basal ganglia among a community-dwelling elder population

PurposeWe examined whether time-course augmentation of perivascular space enlargement in the basal ganglia (BG-PVS) reflected cerebral small vessel disease (CSVD) severity by considering white matter hyperintensity lesion (WMHL) as an indicator for CSVD.Materials and methodsThis study population included 416 older participants from a community-based cohort. They participated in magnetic resonance imaging (MRI) studies more than once during the study period. The grades for BG-PVS and WMHL were evaluated by visual rating scales; BG-PVS time-course augmentation in 4–9 years was also evaluated. At baseline, the participants were asked about their smoking and drinking history, and medical history. They also underwent a blood examination and their office blood pressure (BP) examination. In addition, 24-h ambulatory BP monitoring was also performed within the study period.ResultsOf the 416 participants, 48 participants (11.5%) had BG-PVS time-course augmentation. The participants with BG-PVS augmentation had significantly lower LDL levels, hyper-nighttime BP, and lower nighttime BP fall in univariate analysis (p = 0.03, p = 0.03, p = 0.003, respectively). In multivariate analysis, lower nighttime BP fall and male sex showed significance (p = 0.02, 0.03, respectively). Additionally, BG-PVS time-course augmentation was significantly associated with subsequent WMHL severity in univariate analysis (p < 0.001), which remained significant in multivariate analysis adjusted by imaging and demographic factors (p = 0.03). In multivariate analysis, additionally adjusted by the clinical factors, the significance disappeared (p = 0.07).ConclusionThis study revealed that the lower nighttime BP fall in ambulatory blood pressure monitoring was a factor significantly associated with BG-PVS augmentation. Moreover, the BG-PVS time-course augmentation would be a notable finding that was associated with the subsequent WMHL.

#2851 Effects of dialysis on various microcirculatory beds in end-stage kidney disease (ESKD): a systematic review and meta-analysis

Abstract Background and Aims Microcirculatory dysfunction is common in ESKD-patients and may play a pivotal role in their cardiovascular burden. Besides traditional and chronic-kidney-disease (CKD)-specific risk factors, dialysis itself might contribute to the dysfunction of the microcirculation (MC). Although an intradialytic fall in systemic blood pressure (BP) may directly influence the microcirculatory perfusion, vascular beds in different organs may not react uniformly. This systematic review and meta-analysis evaluated the acute impact of hemodialysis (HD) and hemodiafiltration (HDF) on the MC in various vascular beds. Methods Pubmed and Embase databases were systematically explored until June 2023 by two independent researchers. All observational and interventional studies in ESKD patients that reported dialysis-induced alterations of the MC, measured at the cutaneous, sublingual, retinal, muscle or coronary beds were eligible. Dialysis-induced changes were extracted and pooled, using a fixed-effects meta-analysis when the studies were reasonably homogeneous in terms of outcomes and methodology. Results 17 Studies with 493 participants were included. Virtually all patients (99.8%) were treated with HD. No eligible studies on coronary or muscle MC were identified. Cutaneous MC was investigated in 7 studies, showing a mean reduction in transcutaneous oxygen pressure of −7.9 mmHg (95% CI −10.5 to –5.3, n = 4 studies) and a mean reduction in blood flow of −0.9 arbitrary units (95% CI −1.2 to −0.6, n = 3 studies). Cutaneous vasoreactivity was diminished in 2 out of 3 studies (reactive maximum microvascular hyperemia: −36% (p &amp;lt; 0.05); time to reach baseline skin temperature after standardized cooling: 65.6 seconds (p-value not reported); vs. no significant change in post-ischemic maximal flow (2.5, p = not significant (N.S.)). Sublingual MC was assessed in 3 studies, showing a mean decrease in microvascular flow index of −0.6 in small microvessels (vessel diameter (VD) &amp;lt;20-25 µm, 95% CI −1.0 to −0.2, n = 3 studies), but no significant change in proportion of perfused vessels (−0.5%, 95% CI −1.2 to 0.2, n = 2 studies). One study showed a significant reduction in sublingual perfused vessel density after treatment (VD &amp;lt;20 µm: −1.6 ± 3.1, p &amp;lt; 0.05; VD &amp;gt;20 µm: −0.6 ± 1.1, p &amp;lt; 0.05), whereas total vessel density was unaffected in another study (VD &amp;lt;20 µm: 0.5, p = N.S.). Retinal MC was investigated in 7 studies, showing that the perfused vessel density (PVD) remained unchanged in both the superficial and deep capillary plexus (PVD SCP −0.48, 95% CI (−0.99; 0.03); PVD DCP −0.48, 95% CI (−1.18; 0.23), n = 4 studies). One study reported a decreased PVD at the outer retina (−1.3 ± 5.7, p &amp;lt; 0.05), while conflicting results were observed in 2 studies (0.1, p = N.S.; vs. −2.9 ± 4.3, p &amp;lt; 0.001), reporting the PVD at the choriocapillaris level. One study found no change in retinal blood flow (0.4, p = N.S.). With regard to vessel diameter changes, an increase in retinal venular diameter was observed in 3 studies (retinal venular diameter: 11.2 µm, p = 0.002; central retinal vein equivalent: 12.7 µm, p &amp;lt; 0.001; retinal vessel diameter: 4.4, p &amp;lt; 0.01), and one study described impaired venular dilatation in response to flicker light (−4.0, p = 0.04). Conclusions Hemodialysis induces microvascular dysfunction in different organs, but its impact varies between vascular beds. Microvascular perfusion was most significantly impaired in the cutaneous and sublingual regions, whereas the retinal microcirculatory perfusion remained unaltered. Literature on the effect of hemodiafiltration on the MC is lacking.

#2990 Prevalence and risk factors of altered control of BP during the night in a large hemodialysis population investigated by 48 hours ABPM

Abstract Background and Aims Altered BP control during the night (non-dipping, reverse dipping and nocturnal hypertension) is recognized as a powerful risk factor for death and CV events in the hemodialysis (HD) population. However, these alterations have been described in relatively small studies and the epidemiology and risk factors for subtypes non-dipping and nocturnal hypertension are still poorly characterized in the current literature. We investigated the problem in a large Registry (The EURECAm Registry) that is the sole that adopted state of the art 48 h ABPM recording in the HD population. Method We included in this analysis 534 HD patients, enrolled in 7 centers, led by members of the EURECA-m working group, in 3 European countries. 48 h ABPM was measured by using well validated instruments (AAMI/ESH/ISO). As recommended by the European Society of Hypertension guidelines, recordings were made at 15-minute intervals during the day and 30 minutes during the night. Hypertension was defined as 48 h blood pressure (BP) &amp;gt;130/80, nocturnal hypertension as a nighttime BP &amp;gt;120/70 mmHg, non-dipping as a night/day systolic BP fall &amp;lt;10% and reverse dipping as a night/day ratio &amp;gt;1. Results Among 534 HD patients, 317 were hypertensive and. 217 normotensive. As many as 274 patients were non-dippers (51%), 32% were reverse dippers, and 381 (71%) had nocturnal hypertension. Of note, forty-one per cent of non-dippers, 37% of reverse dippers and 19% of patients with nocturnal hypertension were normotensives. As expected, the majority of reverse dippers (87%) had frank nocturnal hypertension. In a combined analysis of non-dippers and reverse dippers, as compared to dippers, these patients more frequently exhibited atrial fibrillation and had lower Heart Rate both pre-dialysis (72± 11 vs 77±13 bpm, P = 0.004) and post-dialysis (74± 13 vs 78±14 bpm, P = 0.03) and lower serum albumin (3.9±0.4 vs 4.0±0.3 g/dL, P = 0.02) but did not differ for age and gender. Conclusion In a large cohort of HD patients investigated by the state-of-the-art technique, 48 h ABPM alterations in the nocturnal BP profile were almost universal, and nocturnal hypertension was the more prevalent alteration, followed by non-dipping and reverse dipping. These alterations were independent of age and gender. Long-term, granular follow-up analyses are warranted to identify the prognostic value of these alterations.

Effect of Endothelin-1 on Resting Blood Pressure and the Blood Pressure Response to Hypoxia in Healthy Young Men

Objectives: Upregulation of endothelin-1 (ET-1) and its receptors have been linked to increases in hypoxic sensitivity of the carotid chemoreceptors and the development of hypertension. As such, chemoreflex sensitization has been shown in pre-clinical models to be attenuated by ET-1 receptor blockade. Herein, we sought to assess a role for ET-1 in the maintenance of resting blood pressure (BP) in healthy young men and determine whether chemoreflex control of BP could be altered by ET-1 blockade. We hypothesized endothelin receptor antagonism with oral bosentan would lower resting BP in healthy young men as well as the acute BP response to hypoxia. Methods: Twenty-four healthy young men (31±5 yrs, 26±3 kg/m2) completed two study visits (control, bosentan) separated by a minimum of 1 week. The nonspecific endothelin receptor antagonist bosentan (62.5 mg) was taken by mouth twice daily for 3 days prior to the second study visit. On each visit, beat-by-beat BP was assessed under 3 inspiratory air conditions: 1) steady-state normoxia (FiO2 0.21), 2) chemoreflex excitation produced by acute, graded hypoxia (FiO2 0.05 – 0.21), 3) chemoreflex inhibition elicited by transient hyperoxia (FiO2 1.00). Results: Oral bosentan treatment resulted in an increase in plasma ET-1 (0.9±0.9 to 1.3±0.6 pg/mL, p=0.004), supporting receptor blockade. Resting diastolic and mean BP were reduced following 3 days of bosentan treatment compared to control (diastolic: 73±5 to 69±7 mmHg, p=0.007; mean: 93±7 to 88±7 mmHg, p=0.005) with no change in systolic BP (p=0.507). Notably, the BP response to both acute hypoxia (-0.48±0.38 to -0.25±0.31 mmHg/%, p=0.004) and hyperoxia (main effect of bosentan, p=0.025) were attenuated following bosentan. Conclusions: Acute oral bosentan treatment resulted in a reduction in resting BP in healthy young men. The effect of endothelin receptor inhibition with bosentan further attenuated the rise in BP during chemoreflex excitation via acute, graded hypoxia as well as the fall in BP during chemoreflex inhibition (transient hyperoxia). Together these data support a role for ET-1 in control of resting BP in healthy young men, possibly through a chemoreceptor-mediated mechanism. NIH HL130339 (JL), Mayo Clinic Center for Biomedical Discovery (JL, SB). 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.

CAN PATIENTS WITH CARDIOVASCULAR RISK FACTORS AND DIFFERENCE BETWEEN OFFICE AND OUT-OF-OFFICE BP MEASUREMENTS BENEFIT FROM ABPM?

Objective: Blood pressure (BP) is a dynamic parameter characterized by fluctuations during the 24-hour period. During the nighttime hours, BP drops 10-20% in normotensive and untreated hypertensive patients - a dipping phenomenon, followed by a rapid and gradual increase during waking hours. The dipping phenomenon can be checked by Ambulatory Blood Pressure Measurement (ABPM). The main clinical indications for ABPM, suggested by the available studies, are white-coat phenomena, masked hypertension, and nocturnal hypertension. Design and method: Our study involved 45 patients with over 20% difference between office and out-of-office blood pressure measurements. We checked their medical history for other cardiovascular risk factors, such as Dyslipidemia, Diabetes Mellitus, Coronary Disease. Our patients were under 24 hour- ABPM and they were classified according to the rate of fall in systolic BP during 24-hour recording into four categories: the extreme-dippers drop &gt;20%, dippers drop &gt;10% and &lt;20%, non-dippers drop &lt;10% and &gt;0%, and reverse-dippers or risers drop &lt;0%. The purpose of our study is to consider the significance of ABPM in specific target groups of patients with cardiovascular risk factors. Results: In our study 44 patients participated (56,8% men) with mean age 55,9 and mean value of systolic BP 120,7mmHg. 40,9% of the patients had a history of hypertension, 36,4% dyslipidemia, 15,9% diabetes mellitus and 11,4% coronary disease. 77,3% of the patients were judged to be normotensive, but 35,3% of them had a history of hypertension and were under medication, only 11,4% were judged to be hypertensive, 6,8% with isolated diastolic hypertension and 4,5% with isolated systolic hypertension. According to ABPM, we changed medication in 29,5% of the patients. 76.9% of them had already history of hypertension and were under medication, 38,5% had dyslipidemia and 30,7% diabetes mellitus and coronary disease. Conclusions: In our study we were not able to demonstrate that patients with difference between office and out-of-office BP measurements and cardiovascular risk factors could benefit most from ABPM but we demonstrated that patients with a history of hypertension could benefit form ABPM, so that physician could choose the appropriate treatment.

EVALUATION OF THE EFFICACY AND TOLERABILITY OF A FIXED DOSE COMBINATION OF AMLODIPINE AND INDAPAMIDE IN PATIENTS OLDER THAN 55 YEARS

Objective: There is very limited real-life data on hypertension management in Bangladeshi population. Considering this fact, this study evaluated the effectiveness of treatment with an indapamide/amlodipine single-pill combination (SPC) in Bangladeshi patients over the age of 55 years, in an OPD setting with uncontrolled systolic hypertension in real-life clinical practice. Methods: This was a 3-month, multicenter, observational, open-label study conducted in 3 divisional cities of Bangladesh among patients with grade I or II hypertension who were either uncontrolled on previous antihypertensive treatment or treatment-naïve. The effectiveness of indapamide/amlodipine SPC was assessed by the change in office systolic blood pressure (SBP) and the rate of target SBP (&lt; 140 mmHg) achievement at 2 weeks, 1 month and 3 months, in four age groups: 55-59 years, 60-69 years, 70-79 years, and 80 years or older. Design and method: The COMBINE study recruited 213 patients, of whom 185 took indapamide/amlodipine 1.5/5 mg SPC fora full three-month course of therapy. Mean age was 62.4±7.4 years, 76 men [41.1%] and 109 women [58.9%]. The absolute decrease of SBP during 3 months of taking indapamide/amlodipine single-pill combination (SPC) was 29.3 mm Hg, DBP - 12.9 mm Hg. After 3 months of treatment significant SBP decreases from baseline were observed in each age group: ? 31.8 mmHg (from 156.7 to 124.9), ? 26.4 mmHg (from 152.7 to 126.3), ? 29.5 mmHg (from 152.8 to 123.3), and ? 25.8 mmHg (from 151.7 to 125.9) in the 55-59, 60-69, 70-79, and 80 years and older age groups, respectively. Leg edema was observed in 3 patients (1.62%), electrolyte imbalance was observed in 4 patients (2.16%) and 1 patients observed sudden fall of blood pressure. Conclusion: This COMBINE study results showed that indapamide/amlodipine SPC was associated with significant and rapid reductions in BP even in a different age range of Bangladeshi patients in routine clinical practice. This study result is consistent with already achieved data of this SPC globally.

Impact of nocturnal blood pressure dipping on recurrence of atrial fibrillation after pulmonary vein isolation.

Lack of the typical nocturnal blood pressure (BP) fall, i.e non-dipper, has been known as a cardiovascular risk. However, the influence of non-dipper on atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has been unclear. We investigated the clinical impact of non-dipping as evaluated by 24-hour ambulatory BP monitoring on the long-term outcome of AF recurrence post-PVI in 76 AF patients with a history of increased BP. The PVI procedure was successful in all 76 patients (mean age, 66±9years; antihypertensive medication, 89%; non-paroxysmal AF, 24%). Twenty patients had AF recurrence during a median follow-up of 1138 days. There was no difference in BP levels between the AF recurrence and non-recurrence groups (average 24 h systolic BP:126 ± 17 vs.125 ± 14 mmHg; P = 0.84). On the other hand, the patients with non-dipper had a higher AF recurrence than those with dipper (38.9% vs.15.0%; P = 0.018). In Cox hazard analysis adjusted by age, non-paroxysmal AF and average 24-hr systolic BP level, the non-dipper was an independent predictor of AF recurrence (HR 2.78 [95%CI:1.05-7.34], P = 0.039). Non-dipper patients had a larger left atrial (LA) volume index than the dipper patients (45.9 ± 17.3 vs.38.3 ± 10.2 ml/m2, P = 0.037). Among the 58 patients who underwent high-density voltage mapping in LA, 11 patients had a low-voltage area (LVA) defined as an area with a bipolar voltage < 0.5 mV. However, there was no association of LVA with non-dipper or dipper (22.2% vs.16.1%, P = 0.555). Non-dipper is an independent predictor of AF recurrence post-PVI. Management of abnormal diurnal BP variation post-PVI may be important.

Attenuation of hemodynamic response to laryngoscopy and endotracheal intubation using oral ivabradine – Randomised controlled trial

Endotracheal intubation is one of the most common procedures, and anesthesiologists play an important role in patient care. During laryngoscopy and intubation, the patient can experience rapid and drastic hemodynamic changes that are potentially fatal. The purpose of this study is to know the efficacy of ivabradine in attenuating the hemodynamic response to laryngoscopy and endotracheal intubation. In this prospective randomised double-blinded study, fifty patients belonging to ASA 1 and 2 were randomised to group A - ivabradine 5mg (first dose on the evening before the day of surgery and the second dose one hour before intubation). Patients in group B received tablet MVT (placebo) (first dose on the evening before the day of surgery and the second dose one hour before intubation). Patients in group A showed attenuation of heart rate during laryngoscopy and intubation till 10minutes after intubation. Patients in group B showed a rise in blood pressure during laryngoscopy and intubation till 10 minutes after intubation. Patients in group A and group B showed no significant difference in hemodynamics when monitored intraoperatively. All patients recovered fully from anaesthesia and had no complications such as severe bradycardia. Ivabradine effectively attenuates the hemodynamic stress response without a fall in blood pressure and without severe bradycardia.