Postoperative orthostatic intolerance following fast-track unicompartmental knee arthroplasty: incidence and hemodynamics-a prospective observational cohort study.

BACKGROUND: Early postoperative mobilization is essential for early functional recovery but can be inhibited by postoperative orthostatic intolerance (OI). Postoperative OI is common after major surgery, such as total knee arthroplasty (TKA). However, limited data are available after less extensive surgery, such as unicompartmental knee arthroplasty (UKA). We, therefore, investigated the incidence of OI as well as cardiovascular and tissue oxygenation responses during early mobilization after UKA. METHODS: This prospective single-centre observational study included 32 patients undergoing primary UKA. Incidence of OI and cardiovascular and tissue oxygenation responses during mobilization were evaluated preoperatively, at 6 and 24 h after surgery. Perioperative fluid balance, bleeding, surgery duration, postoperative hemoglobin, pain during mobilization and opioid usage were recorded. RESULTS: During mobilization at 6 h after surgery, 4 (14%, 95%CI 4-33%) patients experienced OI; however, no patients terminated the mobilization procedure prematurely. Dizziness and feeling of heat were the most common symptoms. OI was associated with attenuated systolic and mean arterial blood pressure responses in the sitting position (all p < 0.05). At 24 h after surgery, 24 (75%) patients had already been discharged, including three of the four patients with early OI. Only five patients were available for measurements, two of whom experienced OI; one terminated the mobilization procedure due to intolerable symptoms. We observed no statistically significant differences in perioperative fluid balance, bleeding, surgery duration, postoperative hemoglobin, pain, or opioid usage between orthostatic intolerant and tolerant patients. CONCLUSIONS: The incidence of orthostatic intolerance after fast-track unicompartmental knee arthroplasty is low (~ 15%) and is associated with decreased orthostatic pressure responses. Compared to the previously described orthostatic intolerance incidence of ~ 40% following total knee arthroplasty, early orthostatic intolerance is uncommon after unicompartmental knee arthroplasty, suggesting a procedure-specific component. TRIAL REGISTRATION: Prospectively registered at ClinicalTrials.gov; registration number: NCT04195360, registration date: 13.12.2019.

Prevalence of orthostatic intolerance in long covid clinic patients and healthy volunteers: A multicenter study.

Orthostatic intolerance (OI), including postural orthostatic tachycardia syndrome (PoTS) and orthostatic hypotension (OH), are often reported in long covid, but published studies are small with inconsistent results. We sought to estimate the prevalence of objective OI in patients attending long covid clinics and healthy volunteers and associations with OI symptoms and comorbidities. Participants with a diagnosis of long covid were recruited from eight UK long covid clinics, and healthy volunteers from general population. All undertook standardized National Aeronautics and Space Administration Lean Test (NLT). Participants' history of typical OI symptoms (e.g., dizziness, palpitations) before and during the NLT were recorded. Two hundred seventy-seven long covid patients and 50 frequency-matched healthy volunteers were tested. Healthy volunteers had no history of OI symptoms or symptoms during NLT or PoTS, 10% had asymptomatic OH. One hundred thirty (47%) long covid patients had previous history of OI symptoms and 144 (52%) developed symptoms during the NLT. Forty-one (15%) had an abnormal NLT, 20 (7%) met criteria for PoTS, and 21 (8%) had OH. Of patients with an abnormal NLT, 45% had no prior symptoms of OI. Relaxing the diagnostic thresholds for PoTS from two consecutive abnormal readings to one abnormal reading during the NLT, resulted in 11% of long covid participants (an additional 4%) meeting criteria for PoTS, but not in healthy volunteers. More than half of long covid patients experienced OI symptoms during NLT and more than one in 10 patients met the criteria for either PoTS or OH, half of whom did not report previous typical OI symptoms. We therefore recommend all patients attending long covid clinics are offered an NLT and appropriate management commenced.

Orthostatic intolerance after acute mild hypovolemia: incidence, pathophysiologic hemodynamics, and heart-rate variability analysis-a prospective observational cohort study.

PURPOSE: Early postoperative mobilization can be hindered by orthostatic intolerance (OI). Postoperative OI has multifactorial pathogenesis, possibly involving both postoperative hypovolemia and autonomic dysfunction. We aimed to investigate the effect of mild acute blood loss from blood donation simulating postoperative hypovolemia, on both autonomic function and OI, thus eliminating confounding perioperative factors such as inflammation, residual anesthesia, pain, and opioids. METHODS: This prospective observational cohort study included 26 blood donors. Continuous electrocardiogram data were collected during mobilization and night sleep, both before and after blood donation. A Valsalva maneuver and a standardized mobilization procedure were performed immediately before and after blood donation, during which cardiovascular and tissue oxygenation variables were continuously measured by LiDCOrapid™ and Massimo Root™, respectively. The incidence of OI, hemodynamic responses during mobilization and Valsalva maneuver, as well as heart rate variability (HRV) responses during mobilization and sleep were compared before and 15 min after blood donation. RESULTS: Prior to blood donation, no donors experienced OI during mobilization. After blood donation, 6/26 (23%; 95% CI, 9 to 44) donors experienced at least one OI symptom. Three out of 26 donors (12%; 95% CI, 2 to 30) terminated the mobilization procedure prematurely because of severe OI symptoms. Cardiovascular and cerebral tissue oxygenation responses were reduced in patients with severe OI. After blood loss, HRV indices of total autonomic power remained unchanged but increased sympathetic and decreased parasympathetic outflow was observed during mobilization, but also during sleep, indicating a prolonged autonomic effect of hypovolemia. CONCLUSION: We describe a specific hypovolemic component of postoperative OI, independent of postoperative autonomic dysfunction, inflammation, opioids, and pain. STUDY REGISTRATION: ClinicalTrials.gov (NCT04499664); registered 5 August 2020.

RéSUMé: OBJECTIF: La mobilisation postopératoire précoce peut être entravée par une intolérance orthostatique (IO). L'IO postopératoire a une pathogenèse multifactorielle, impliquant peut-être à la fois une hypovolémie postopératoire et un dysfonctionnement autonome. Notre objectif était d'étudier l'effet d'une légère perte de sang aiguë due au don de sang simulant une hypovolémie postopératoire, à la fois sur la fonction autonome et sur l'IO, éliminant ainsi les facteurs périopératoires confondants tels que l'inflammation, l'anesthésie résiduelle, la douleur et les opioïdes. MéTHODE: Cette étude de cohorte observationnelle prospective comprenait 26 personnes ayant donné leur sang. Des données d'électrocardiogramme continu ont été recueillies pendant la mobilisation et le sommeil nocturne, avant et après le don de sang. Une manœuvre de Valsalva et une procédure de mobilisation standardisée ont été réalisées immédiatement avant et après le don de sang, au cours desquelles les variables d'oxygénation cardiovasculaire et tissulaire ont été mesurées en continu avec les moniteurs LiDCOrapid™ et Massimo Root™, respectivement. L'incidence d'IO, les réponses hémodynamiques pendant la mobilisation et la manœuvre de Valsalva, ainsi que les réponses de variabilité de la fréquence cardiaque (VFC) pendant la mobilisation et le sommeil ont été comparées avant et 15 minutes après le don de sang. RéSULTATS: Avant le don de sang, aucune personne ayant fait un don de sang n'a ressenti d'IO pendant la mobilisation. Après le don de sang, 6/26 (23 %; IC 95 %, 9 à 44) des donneurs et donneuses ont manifesté au moins un symptôme d'IO. Trois personnes sur 26 (12 %; IC 95 %, 2 à 30) ont interrompu prématurément la procédure de mobilisation en raison de symptômes graves d'IO. Les réponses d'oxygénation des tissus cardiovasculaires et cérébraux ont été réduites chez les personnes atteintes d'IO sévère. Après la perte de sang, les indices de VFC de la puissance totale autonome sont demeurés inchangés, mais une augmentation du flux sympathique et une diminution du flux parasympathique ont été observées pendant la mobilisation, mais également pendant le sommeil, indiquant un effet autonome prolongé de l'hypovolémie. CONCLUSION: Nous décrivons une composante spécifique hypovolémique de l'IO postopératoire, indépendante du dysfonctionnement autonome postopératoire, de l'inflammation, des opioïdes et de la douleur. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT04499664); enregistrée le 5 août 2020.

[A 10-year retrospective analysis of spectrums and treatment options of orthostatic intolerance and sitting intolerance in children].

OBJECTIVE: To analyze the disease spectrums underlying orthostatic intolerance (OI) and sitting intolerance (SI) in Chinese children, and to understand the clinical empirical treatment options. METHODS: The medical records including history, physical examination, laboratory examination, and imagological examination of children were retrospectively studied in Peking University First Hospital from 2012 to 2021. All the children who met the diagnostic criteria of OI and SI were enrolled in the study. The disease spectrums underlying OI and SI and treatment options during the last 10 years were analyzed. RESULTS: A total of 2 110 cases of OI and SI patients were collected in the last 10 years, including 943 males (44.69%) and 1 167 females (55.31%) aged 4－18 years, with an average of (11.34±2.84) years. The overall case number was in an increasing trend over the year. In the OI spectrum, postural tachycardia syndrome (POTS) accounted for 826 cases (39.15%), followed by vasovagal syncope (VVS) (634 cases, 30.05%). The highest proportion of SI spectrum was sitting tachycardia (STS) (8 cases, 0.38%), followed by sitting hypertension (SHT) (2 cases, 0.09%). The most common comorbidity of OI and SI was POTS coexisting with STS (36 cases, 1.71%). The highest proportion of treatment options was autonomic nerve function exercise (757 cases, 35.88%), followed by oral rehydration salts (ORS) (687 cases, 32.56%), metoprolol (307 cases, 14.55%), midodrine (142 cases, 6.73%), ORS plus metoprolol (138 cases, 6.54%), and ORS plus midodrine (79 cases, 3.74%). The patients with POTS coexisting with VVS were more likely to receive pharmacological intervention than the patients with POTS and the patients with VVS (41.95% vs. 30.51% vs. 28.08%, χ2= 20.319, P < 0.01), but there was no significant difference in the proportion of treatment options between the patients with POTS and the patients with VVS. CONCLUSION: POTS and VVS in children are the main underlying diseases of OI, while SI is a new disease discovered recently. The number of children with OI and SI showed an increasing trend. The main treatment methods are autonomic nerve function exercise and ORS. Children with VVS coexisting with POTS were more likely to take pharmacological treatments than those with VVS or POTS only.

Postural orthostatic tachycardia syndrome as a sequela of COVID-19.

Postural orthostatic tachycardia syndrome (POTS) is a complex multisystem disorder characterized by orthostatic intolerance and tachycardia and may be triggered by viral infection. Recent reports indicate that 2%-14% of coronavirus disease 2019 (COVID-19) survivors develop POTS and 9%-61% experience POTS-like symptoms, such as tachycardia, orthostatic intolerance, fatigue, and cognitive impairment within 6-8 months of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Pathophysiological mechanisms of post-COVID-19 POTS are not well understood. Current hypotheses include autoimmunity related to SARS-CoV-2 infection, autonomic dysfunction, direct toxic injury by SARS-CoV-2 to the autonomic nervous system, and invasion of the central nervous system by SARS-CoV-2. Practitioners should actively assess POTS in patients with post-acute COVID-19 syndrome symptoms. Given that the symptoms of post-COVID-19 POTS are predominantly chronic orthostatic tachycardia, lifestyle modifications in combination with the use of heart rate-lowering medications along with other pharmacotherapies should be considered. For example, ivabradine or ß-blockers in combination with compression stockings and increasing salt and fluid intake has shown potential. Treatment teams should be multidisciplinary, including physicians of various specialties, nurses, psychologists, and physiotherapists. Additionally, more resources to adequately care for this patient population are urgently needed given the increased demand for autonomic specialists and clinics since the start of the COVID-19 pandemic. Considering our limited understanding of post-COVID-19 POTS, further research on topics such as its natural history, pathophysiological mechanisms, and ideal treatment is warranted. This review evaluates the current literature available on the associations between COVID-19 and POTS, possible mechanisms, patient assessment, treatments, and future directions to improving our understanding of post-COVID-19 POTS.

Orthostatic intolerance after fast-track knee arthroplasty: Incidence and hemodynamic pathophysiology.

BACKGROUND: Early postoperative mobilization can be hindered by orthostatic intolerance (OI) due to failed orthostatic cardiovascular regulation. The underlying mechanisms are not fully understood and specific data after total knee arthroplasty (TKA) are lacking. Therefore, we evaluated the incidence of OI and the cardiovascular response to mobilization in fast-track TKA. METHODS: This prospective observational cohort study included 45 patients scheduled for primary TKA in spinal anesthesia with a multimodal opioid-sparing analgesic regime. OI and the cardiovascular response to sitting and standing were evaluated with a standardized mobilization procedure preoperatively, and at 6 and 24 h postoperatively. Hemodynamic variables were measured non-invasively (LiDCO™ Rapid). Perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, opioid use, and pain during mobilization were recorded. RESULTS: Eighteen (44%) and 8 (22%) patients demonstrated OI at 6 and 24 h after surgery, respectively. Four (10%) and 2 (5%) patients experienced severe OI and terminated the mobilization procedure prematurely. Dizziness was the most common OI symptom during mobilization at 6 h. OI was associated with decreased orthostatic responses in systolic, diastolic, mean arterial pressures, and heart rate (all p < .05), while severe OI patients demonstrated impaired diastolic, mean arterial pressures, heart rate, and cardiac output responses (all p < .05). No statistically significant differences in perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, pain, or opioid use were observed between orthostatic tolerant and intolerant patients. CONCLUSION: Early postoperative OI is common following fast-track TKA. Pathophysiologic mechanisms include impaired orthostatic cardiovascular responses. The progression to severe OI symptoms appears to be primarily due to inadequate heart rate response.

The prevalence and impact of orthostatic intolerance in young women across the hypermobility spectrum.

Orthostatic intolerance (OI) is frequently reported in young women with generalized hypermobility spectrum disorder (G-HSD) and hypermobile EDS (hEDS). However, it remains currently unclear whether OI is a comorbidity or fundamental part of the pathophysiology of G-HSD or hEDS. This study investigated the prevalence and impact of OI in young women across the hypermobility spectrum. Forty-five women (14-30 years, 15 controls, 15 G-HSD, and 15 hEDS) undertook a head-up tilt (HUT) and active stand test. Postural Orthostatic Tachycardia Syndrome (POTS) and Orthostatic Hypotension (OH) were assessed using age-related criteria. Autonomic dysfunction and quality-of-life questionnaires were also completed. The prevalence of POTS was higher in women with G-HSD than hEDS and control groups during HUT (43% vs. 7% and 7%, respectively, p < 0.05), but similar between groups during the active stand (47%, 27%, and 13% for G-HSD, hEDS, and control, respectively). No participants had OH. hEDS and G-HSD participants reported more severe orthostatic symptoms and poorer quality of life than controls. Although POTS was observed in hypermobile participants, there is no conclusive evidence that its prevalence differed between groups due to differences between the HUT and active stand assessments. Nevertheless, OI and broader autonomic dysfunction impacted on their quality of life.

Incidence and Risk Factors of Orthostasis After Primary Hip and Knee Arthroplasty.

BACKGROUND: Postoperative orthostatic intolerance can limit mobilization after hip and knee arthroplasty. The literature is lacking on the incidence and risk factors associated with orthostatic intolerance after elective arthroplasty. METHODS: A retrospective case-control study of primary total hip, total knee, and unicompartmental knee arthroplasty patients was conducted. Patients with orthostatic events were identified, and potential demographic and perioperative risk factors were recorded. Orthostatic intolerance was defined as postoperative syncope, lightheadedness, or dizziness, limiting ambulation and/or requiring medical treatment. Statistical analysis was completed using Pearson's chi-square test for categorical data and t-tests for continuous data. Binary logistic regression was performed. RESULTS: A total of 500 consecutive patients were included. The overall incidence of orthostatic intolerance was 18%; 25% in total hip arthroplasty (THA) and 11% in total knee arthroplasty. On univariate analysis, significant risk factors for developing postoperative orthostatic intolerance include older age, female gender, THA surgery, lower American Society of Anesthesiologists class, absence of recreational drug use, lower estimated blood volume, lower preoperative diastolic blood pressure, spinal with monitored anesthesia care (MAC), posterior approach for THA, bupivacaine use in spinal, percent of blood loss, postoperative oxycodone or tramadol use, higher postoperative intravenous fluid volume, and lower postoperative hemoglobin. Multivariate analysis demonstrated persistent significance of female gender, THA surgery, spinal with MAC, bupivacaine use in spinal, and more intravenous fluid administered postoperatively. CONCLUSION: Orthostatic intolerance affects a significant number of arthroplasty patients. Awareness of risk factors and modification of perioperative variables linked to orthostatic intolerance may assist the surgeon in choosing the appropriate surgical setting, educating patients, and improving early postoperative recovery.

The impact of orthostatic intolerance on early ambulation following abdominal surgery in an enhanced recovery programme.

BACKGROUND: The prevalence of orthostatic intolerance on the day of surgery is more than 50% after abdominal surgery. The impact of orthostatic intolerance on ambulation on the day of surgery has been little studied. We investigated orthostatic intolerance and walking ability after colorectal and bariatric surgery in an enhanced recovery programme. METHODS: Eighty-two patients (colorectal: n = 46, bariatric n = 36) were included and analysed in this prospective study. Walk tests for 2 min (2-MWT) and 6 min (6-MWT) were performed before and 24 h after surgery, and 3 h after surgery for 2-MWT. Orthostatic intolerance characterised by presyncopal symptoms when rising was recorded at the same time points. Multivariate binary logistic regressions modelling the probability of orthostatic intolerance and walking inability were performed taking into account potential risk factors. RESULTS: Prevalence of orthostatic intolerance and walking inability was, respectively, 65% and 18% 3-hour after surgery. The day after surgery, patients' performance had greatly improved: approximately 20% of the patients experienced orthostatic intolerance, whilst only 5% of the patients were unable to walk. Adjusted binary logistic regressions demonstrated that age (p = .37), sex (p = .39), BMI (p = .74), duration of anaesthesia (p = .71) and type of surgery (p = .71) did not significantly influence walking ability. CONCLUSION: Our study confirms that orthostatic intolerance was frequent (~ 60%) 3-hour after abdominal surgery but prevented a 2-MWT only in ~20% of patients. No risk factors for orthostatic intolerance and walking inability were evidenced.

Orthostatic intolerance: a frailty marker for older adults.

PURPOSE: Frailty, orthostatic blood pressure changes (OBPC), and orthostatic intolerance syndrome (OIS) are common in geriatric patients. However, the results of the studies evaluating the relationship between these entities are discordant. We aimed to investigate the association between frailty and OIS with or without OBPC. METHODS: Comprehensive geriatric assessment (CGA), frailty assessment, OBPC evaluations in the active-standing test (1st, 3rd, 5th, and 10th min), OIS investigation both in history before the test (self-reported OIS) and emerged during the active-standing test, and sarcopenia assessment via BIA and handgrip strength (HGS) were performed in 102 geriatric outpatients. RESULTS: Patients were divided into three categories according to their frailty status (non-frail, prefrail, and frail) by Modified Fried Frailty Index (FFI) and Clinical Frailty Scale (CFS). Prevalence of self-reported OIS and OIS during the test were statistically higher in the frail group assessed by both frailty scales (P value: 0.001 for CFS, P value < 0.0001 for FFI, and P value: 0.001 for CFS, P value: 0.007 for FFI, respectively). Logistic regression analysis showed that OIS significantly increased frailty assessed both by FFI and CFS, when adjusted for age, sex, comorbidities, CGA, and sarcopenia (For FFI, OR: 19.37; 95% CI: 2.38-157.14; P value: 0.006 and for CFS OR: 4.32; 95% CI: 1.184-11.47; P value: 0.003, respectively). CONCLUSION: To the best of our knowledge, this is the first study defining OIS as symptoms both self-reported and provoked during the test, and showed a strong correlation between OIS and frailty. OIS may be defined as a multifactorial and independent marker for frailty, regardless of OBPC. Further prospective investigations are warranted to support the relationships between OIS and frailty.

Orthostatic intolerance in post-concussion patients.

Orthostatic intolerance (OI) following pediatric concussion is not well understood. Assessing the prevalence of concussion-related OI and how it compares to non-concussion-related OI will improve care for patients suffering with these symptoms. OBJECTIVE: We set out to describe concussion-related OI in adolescence, with particular emphasis on time to recovery and differences from non-concussion-related OI (including male vs. female prevalence). Retrospective chart reviews were completed on post-concussion patients endorsing symptoms of OI. The patients' sex, sport history, previous concussions, time since injury, and recovery time were analyzed and compared between males and females as well as against general OI statistics. Thirty-nine pediatric patients, representing 8.7% of all new patients referred to a specialized concussion clinic over a 13-month interval, were included in the chart review. Mean age of onset was 15.0 ± 2.5 years and 18 (46%) were males. The median times from evaluation to symptom resolution were 120 days. Of 18 patients who completed head-up tilt table testing, 17 (94%) had orthostatic tachycardic response (>40 bpm heart rate increment). Post-concussive OI differs from other orthostatic intolerance etiologies, lacking a strong female predominance and exhibiting a shorter time course to recovery compared to other etiologies of OI (but longer recovery time compared to concussion patients in general). Clinical orthostatic vital signs may not be sensitive for diagnosing orthostatic intolerance in athletes, likely due to higher vagal tone and more efficient skeletal muscle pump.

Orthostatic Hypotension and Orthostatic Intolerance Symptoms in Geriatric Rehabilitation Inpatients, RESORT.

OBJECTIVES: Orthostatic hypotension (OH) and orthostatic intolerance symptoms are common in older community-dwelling adults and are associated with reduced quality of life and detrimental health outcomes. This study aimed to determine the prevalence, co-occurrence and determinants of OH and orthostatic intolerance symptoms in geriatric rehabilitation inpatients. DESIGN: Observational, longitudinal cohort, "REStORing the health of acutely unwell adulTs" (RESORT). SETTING AND PARTICIPANTS: Geriatric rehabilitation inpatients (n = 1505) of a tertiary teaching hospital in Melbourne, Australia. METHODS: OH was defined as a drop in systolic blood pressure by ≥20 mm Hg and/or diastolic blood pressure by ≥10 mm Hg within three 3 of moving from supine to a standing or sitting position. Symptoms were recorded following the 3 minutes. Determinants included sociodemographics, reason for admission, cognitive health, nutritional status, physical performance, frailty, morbidity, medication use, length of stay (LOS), and number of geriatric conditions. Independent t-tests, Mann-Whitney U tests or χ2 tests were used to analyze differences between inpatients with and without OH and symptoms. Logistic regression analyses were used to ascertain the determinants. RESULTS: OH and orthostatic intolerance symptoms were prevalent in 19.8% (standing: 21.4%, sitting: 18.2%) and 22.6% (standing: 25.0%, sitting: 20.2%) of inpatients, respectively. Symptoms were reported by 32.8% of inpatients with OH and 20.1% without OH. Higher number of comorbidities and geriatric conditions, low functional independence, and longer LOS were determinants of OH. Female gender, higher number of morbidities and geriatric conditions, low functional independence, depression risk, poor physical performance, musculoskeletal and "other" reasons for admission, and long LOS during geriatric rehabilitation were determinants of symptoms. CONCLUSIONS AND IMPLICATIONS: OH and orthostatic intolerance symptoms occur in one-fifth of geriatric rehabilitation inpatients, however, the co-occurrence is low and determinants differ. Poorer health in patients with orthostatic intolerance symptoms highlights the need to assess symptoms in clinical practice, independent of an OH diagnosis.

Orthostatic intolerance after bariatric surgery: A systematic review and meta-analysis.

There have been increased reports of orthostatic intolerance post-bariatric surgery. However, the prevalence, pathophysiology and long-term outcomes have not been well described. Therefore, we sought to summarize evidence of orthostatic intolerance after bariatric surgery. We conducted a systematic review using PubMed, Scopus, CINAHL, Cochrane Database of Systematic Reviews and the Cochrane Central Register of Controlled Trials (CENTRAL) to identify relevant articles from the date of inception until 1st April 2020. Study selection, data extraction and quality assessment of the included studies were performed independently by two reviewers. The findings of the included studies were narratively reported. When feasible, a meta-analysis was done to summarize the relevant results. We included 20 studies (n = 19 843 participants) reporting findings of 12 prospective cohort studies, 5 retrospective cohort studies, 2 cross-sectional studies and one randomized controlled trial. The 5-year cumulative incidence of orthostatic intolerance was 4.2% (one study). Common clinical presentations of orthostatic intolerance were lightheadedness, dizziness, syncope and palpitation. The pooled data suggested improvement in overall cardiac autonomic function (sympathetic and parasympathetic) post-bariatric surgery. In addition, a significant systolic blood pressure drop may reflect a reset of the balance between the sympathetic and parasympathetic nervous systems after weight loss in the pooled analysis. Existing literature on orthostatic intolerance post-bariatric surgeries was limited or of low quality, and larger studies are needed to know the true incidence of orthostatic intolerance post-bariatric surgeries and the pathophysiology. We found one study reporting the 5-years cumulative incidence of orthostatic intolerance post-bariatric surgeries as only 4.2%. This could challenge the idea of increased orthostatic intolerance prevalence post-bariatric surgeries. Registration The review protocol was registered at the International Prospective Register of Systemic Reviews PROSPERO (CRD42020170877).

Orthostatic Intolerance after Bariatric Surgery: a Systematic Review.

Predisposing factors of new-onset orthostatic intolerance (OI) after bariatric surgery (BS) are unknown. The purpose of this study is to summarize current existing data on new-onset OI after BS. Materials and methods were considered for a search of articles that were published by the 30th of July 2020. A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and in line with the protocol agreed by all authors was conducted. Of the 604 initially identified articles, four studies were found to match the established criteria and were extracted for eligibility. 83.3% were female. Hypertension, type 2 diabetes mellitus, and obstructive sleep apnea syndrome were the most frequently reported comorbidities. Surgical intervention such as revision, conversion, or reversal was not documented in these studies. Awareness of this issue must be raised due to the possibility of reduced quality of life and the risk of syncope.

Mechanisms and management of gastrointestinal symptoms in postural orthostatic tachycardia syndrome.

Postural orthostatic tachycardia syndrome (POTS) is a disorder of orthostatic intolerance associated with many GI manifestations that can be broadly classified into two different categories: those present all the time (non-positional) and those that occur with orthostatic position change. There are also many conditions that can co-exist with POTS such as mast cell activation syndrome and the hypermobile form of Ehlers-Danlos syndrome (hEDS) that are also oftentimes associated with GI symptoms. In the current issue of Neurogastroenterology and Motility, Tai et al. explored the relationship between functional GI disorders among hEDS patients with and without concomitant POTS and showed that the hEDS-POTS cohort was more likely to have more than one GI organ involved compared to the cohort with hEDS alone, and certain GI symptoms were also more common in the hEDS-POTS cohort. In this review article, we will briefly review the literature surrounding putative mechanisms responsible for GI symptoms in POTS with an emphasis on the contributory role of concomitant hEDS and then discuss management strategies for GI symptoms in POTS.

Demographic and clinical features of pediatric patients with orthostatic intolerance and an abnormal head-up tilt table test; A retrospective descriptive study.

BACKGROUND: Clinical presentation varies in children with Orthostatic Intolerance. This study aimed to evaluate the epidemiological and clinical characteristics of pediatric patients with orthostatic intolerance (OI) and positive head-up tilt test (HUTT). METHODS: This study was a retrospective review of clinical data from outpatients over 18 months period. RESULTS: We included 112 patients with abnormal HUTT results. Females were 78 (70%). Mean age of presentation was 15.6 years (sd: 3.3). Fifteen percent were overweight, and 14% were obese. A headache and syncope were the most frequent presenting symptoms (46% and 29% respectively). Review of systems identified more patients with headaches (84%), Syncope (61%), presyncope (87%) and abdominal pain (29%). Except for fatigue being more prevalent during a review of systems among patients with severe OI (69%) compared to those with moderate OI (46%, p = 0.02), there was no statistically significant difference in the clinical presentation between investigator-defined moderate and severe OI. Comorbidities identified in this cohort were Chiari malformations (9%), idiopathic intracranial hypertension (9%), electroencephalographic abnormalities (8%) and patent foramen ovale (43%). CONCLUSIONS: Adolescents, mainly females had OI. Patients with OI and abnormal HUTT predominantly had a headache, syncope, and presyncope during the presentation. Eliciting review of systems and using tools such as clinical questionnaire identifies significant clinical presenting features and comorbidities.

Autonomic cardiovascular control changes in recent heart transplant recipients lead to physiological limitations in response to orthostatic challenge and isometric exercise.

PURPOSE: Heart transplantation causes denervation of the donor heart, but the consequences for cardiovascular homeostasis remain to be fully understood. The present study investigated cardiovascular autonomic control at supine rest, during orthostatic challenge and during isometric exercise in heart transplant recipients (HTxR). METHODS: A total of 50 HTxRs were investigated 7-12 weeks after transplant surgery and compared with 50 healthy control subjects. Continuous, noninvasive recordings of cardiovascular variables were carried out at supine rest, during 15 min of 60° head-up tilt and during 1 min of 30% of maximal voluntary handgrip. Plasma and urine catecholamines were assayed, and symptoms were charted. RESULTS: At supine rest, heart rate, blood pressures and total peripheral resistance were higher, and stroke volume and end diastolic volume were lower in the HTxR group. During tilt, heart rate, blood pressures and total peripheral resistance increased less, and stroke volume and end diastolic volume decreased less. During handgrip, heart rate and cardiac output increased less, and stroke volume and end diastolic volume decreased less. Orthostatic symptoms were similar across the groups, but the HTxRs complained more of pale and cold hands. CONCLUSION: HTxRs are characterized by elevated blood pressures and total peripheral resistance at supine rest as well as attenuated blood pressures and total peripheral resistance responses during orthostatic challenge, possibly caused by low-pressure cardiopulmonary baroreceptor denervation. In addition, HTxRs show attenuated cardiac output response during isometric exercise due to efferent sympathetic denervation. These physiological limitations might have negative functional consequences.

Effect of verticalization with Erigo® in the acute rehabilitation of severe acquired brain injury.

The recovery of the orthostatism after a severe acquired brain injury (sABI) is an essential objective to pursue in order to avoid the occurrence of secondary complications resulting from prolonged immobilization to which the patient is subjected during the acute phase. This randomized controlled trial aims to evaluate the effect of verticalization with the lower limb robot-assisted training system Erigo® versus conventional neurorehabilitation in 44 adult subjects affected by sequelae of sABI in the acute rehabilitation phase, related to cardiorespiratory signs and measures of impairment and activity. At the end of the study (20 treatment sessions, 5 sessions per week), in both groups of patients, there were no dropouts nor adverse events. In subject verticalized with Erigo®, there were no episodes of (pre)syncope from orthostatic hypotension nor postural orthostatic tachycardia and cardiorespiratory signs remained stable; moreover, there were no increase in muscle tone nor reduction in range of motion at lower limbs. Results obtained show improved outcomes on the whole and in a similar way in both groups; however, the improvement in scores of the National Institutes of Health Stroke Scale, the Tinetti scale, and the Functional Independence Measure from the enrollment to the end of the treatment cycle being equal, the evaluation performed at the 10th session allows to establish that the improvement appears earlier in the intervention group and later in the control group. The more rapid recovery of impairments and some activities in subjects treated with Erigo® could allow a "time-saver" to devote to the rehabilitation of sensory-motor functions which are more complex and subordinated to the preliminary reacquisition of elementary postures and motor strategies.

Prevalence and frequency of self-perceived systemic features in people with joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type.

Some commonly reported systemic features of joint hypermobility syndrome (JHS)/Ehlers-Danlos syndrome hypermobility type (EDS-HT) are absent from nosologies due to insufficient validity. The primary aim was to examine the hypothesised high prevalence and frequency of orthostatic intolerance, easy bruising, and urinary incontinence in adults with JHS/EDS-HT and secondarily to determine the association between extent of generalised joint hypermobility (GJH) and these systemic features. A cross-sectional cohort study was conducted via online recruitment of medically diagnosed JHS/EDS-HT patients. A survey collected demographic data and clinical history. A subgroup of participants underwent physical testing of GJH using the Beighton score and Lower Limb Assessment Score (LLAS). Descriptive analysis was performed on demographic data and self-reported non-musculoskeletal systemic features. Correlation of GJH scores and systemic features were performed using Spearman's rank correlation. The survey was completed by 116 individuals (95% female; 16-68 years) with 57 (93% female) also participating in the physical assessment. The most prevalent systemic feature was orthostatic intolerance (98%), followed by easy bruising and urinary incontinence (97% and 84% respectively). Of those reporting symptoms of orthostatic intolerance, easy bruising, and urinary incontinence, 58%, 40%, and 18% described them as very highly frequent respectively (frequency > 75%). No significant correlations were found between the extent of systemic features and GJH scores as measured by either the Beighton score or the LLAS. The high prevalence and frequency of the systemic features found in this study, which are omitted in diagnostic classification criteria, suggest that further research on their diagnostic accuracy is warranted.