Orthostatic hypotension: definition, diagnosis and management

Exploring 5-minute heart rate variability in spinal cord injury during acute inpatient rehabilitation

To explore the use of 5-minute heart rate variability (HRV) during inpatient rehabilitation in the acute phase of traumatic spinal cord injury (SCI). Longitudinal observational study. Acute inpatient rehabilitation (AIR). 10 patients with acute traumatic SCI. 5-minute HRV supine recordings twice daily on three different days per patient. HRV values were evaluated (1) within a single day (Early versus Late); (2) across the inpatient admission (initial, mid, and discharge); (3) by SCI phenotypes and by clinical outcomes (ex. pressure injuries (PI)). Patients had an average age of 38 years, 80% male, and 40% with tetraplegia. There were no HRV differences between Early and Late recordings, across the inpatient admission, demographics, or SCI phenotype. However, improvement in neurologic exam was accompanied by increased parasympathetic tone (mean RR increased by 172 ms SD 61, P = .005). Patients with PI demonstrated lower sympathetic (SNS) activity (decreased LF by 472 ms² SD 240, P = .049) and lower PNS activity (decreased RMSSD by 1.2 ms SD 0.5, P = .02), compared to no PI. Comparisons to uninjured reference values and chronic SCI suggest a changing autonomic nervous system (ANS) from uninjured to acute to chronic as measured by HRV.

CONCLUSIONS

This preliminary evidence suggests HRV in acute SCI is stable across time and day during inpatient rehabilitation and may be correlated to clinical sequalae of ANS dysfunction and neurologic recovery. Comparisons to published work suggest that HRV may measure the progression in the ANS from acute to chronic phase after SCI.

Symptoms, Surgical Events, and Length of Stay of Surgical Oncology Outpatients

PURPOSE

This study examined the incidence of postanesthesia symptoms, postoperative events, and length of stay (LOS) for surgical oncology outpatients in Phase II recovery during three time periods: before, one-month post, and one-year after the implementation of revised PACU I to PACU II transfer procedures and discharge criteria.

DESIGN

Data for this retrospective analysis was obtained from the organizations' electronic medical records during the timeframe April 3, 2017 through August 5, 2018 after enhanced PACU I to PACU II transfer procedures were implemented on June 5, 2017. Records of surgical outpatients transferred from PACU I to PACU II who received regional pain control or preoperative anti-emetics were excluded from the analysis.

METHODS

Study approval was obtained through the Institutional Review Board [#19-308]. The records [n = 1091] were sorted and analyzed according to symptoms, events, and length of recovery. Incidence of symptoms, use of IV fluids, and medications administered in PACU II was tabulated for each time-period. Kruskal-Wallis tests were used to detect differences in length of stay variables across the three time periods.

FINDINGS

A significant decrease in PACU II LOS was observed following the implementation of revised PACU I to PACU II transfer criteria (P< .001). Although blood pressure changes decreased between each time period: 1.4% (T-1), 0.3% (T-2), and 0.2% (T-3), postanesthesia symptoms [dizziness, pain, and nausea] decreased from T-1 to T-2, with a small increase in T-3. The use of fentanyl and continuous IV fluids decreased between all time periods.

CONCLUSIONS

Monitoring key variables related to patient outcomes involving LOS and symptom management ensures sustained practice changes, improves care, and optimizes surgical outpatient experience.

Orthostatic hypotension following posterior spinal fusion surgeries for spinal deformity correction in adolescents: prevalence and risk factors

Study design

Retrospective case series.

Objectives

This study aimed to determine the prevalence and risk factors for orthostatic hypotension (OH) in adolescents undergoing posterior spinal fusion for spinal deformity correction.

Methods

The data of 282 consecutive adolescents who underwent posterior spinal fusion for spinal deformity correction in our center over 12 months were retrieved. Patient characteristics, including whether laminectomy or osteotomy was performed during the surgery, the occurrence of postoperative nausea and vomiting (PONV), perioperative hemoglobin albumin changes, perioperative blood transfusion, length of bed rest, willingness to ambulate, length of postoperative exercises of the lower limbs, and length of hospital stay, were collected and compared statistically between patients who did and did not develop postoperative OH.

Results

Of 282 patients, 197 (69.86%) developed OH postoperatively, and all cases completely resolved 5 days after the first out-of-bed exercises. Significant differences in the incidence of PONV, the willingness to ambulate and the length of postoperative exercises of the lower limbs were observed. The mean length of hospital stay of the patients with OH was longer than that of the patients without OH.

Conclusion

Our study suggests that temporary OH is a common manifestation following posterior spinal fusion for spinal deformity correction in adolescents. Postoperative OH may increase the length of hospital stay in these patients. Patients with PONV, who are not willing to ambulate and who perform postoperative lower limb exercises for a shorter time are more likely to have OH.

Orthostatic Hypotension in Male Hypertensive Patients: A Cross-Sectional Study at the University of Gondar Comprehensive Specialized Hospital, Gondar, Ethiopia

Background

Orthostatic hypotension (OH) is defined as a fall in systolic blood pressure (SBP) ≥20 mmHg or diastolic BP (DBP) ≥10 mmHg within 3 minutes of standing. OH incidence is increased with hypertension, and management of these patients may pose challenges, as treatment of one can worsen the other.

Objective

This study aimed to determine the prevalence of OH and its associated factors among male hypertensive patients at the University of Gondar Comprehensive Specialized Hospital, Gondar, Ethiopia.

Methods

A hospital-based cross-sectional design was employed. Seated BP was measured twice and the average of the two taken. After BP had been stabilized for 5 minutes, SBP within 3 minutes of standing was measured twice and the minimum of the two taken. A drop of ≥20 mmHg in SBP within 3 minutes of standing was taken as OH. All male hypertensive patients who were able to attain a standing position were included. Sociodemographic, anthropometric, and clinical status of the patients were taken using structured interviewer-administered questionnaires. Data were entered and analyzed using SPSS 21. Both bivariate and multivariate logistic regression analysis were done. P≤0.05 was considered statistically significant.

Results

The median age of study participants was 57 (25–96) years. The prevalence of OH was 17.6%. Uncontrolled hypertension (adjusted OR 2.08, 95% CI 1.125–3.872) and duration of hypertension ≥5 years (adjusted OR 2.04, 95% CI 1.069–3.895) were significantly associated with OH in hypertensive patients.

Conclusion

The prevalence of OH among male hypertensive patients was high. Hypertensive patients whose BP was uncontrolled and having had hypertension ≥5 years were risk factors of OH.

Prevention and Management of Supine Hypertension in Patients With Orthostatic Hypotension

BACKGROUND

Orthostatic hypotension (OH) is a potentially debilitating condition caused by dysfunction of the autonomic nervous system, which is essential for the physiologic response to orthostatic posture. In addition to OH, autonomic dysfunction may also be associated with the development of concurrent supine hypertension (SH).

AREAS OF UNCERTAINTY

This paradoxical effect speaks to the complexity of the pathogenesis of autonomic disease and greatly complicates management of these patients. Clinicians are faced with a dilemma because aggressive treatment of orthostatic intolerance can worsen supine hypertension and attempts to control supine hypertension can worsen orthostatic intolerance.

DATA SOURCES

Systematic review of the published literature.

PREVENTION OF SUPINE HYPERTENSION

Patients should aim to avoid known stressors, perform physical maneuvers (eg, slowly getting up from bed, sleeping with head of bed elevated), manage underlying related conditions (eg, diabetes mellitus), and exercise.

MANAGEMENT OF SUPINE HYPERTENSION

With failure of conservative management, patients may advance to pharmacologic therapy. It is important to understand the underlying suspected etiology of the syndrome of supine hypertension and OH (SH-OH) to select promising pharmacologic agents. This article reviews medical treatment options to work toward achieving a better quality of life for patients afflicted with this disease. Although clonidine and beta-blockers can be used to treat hypertension without causing significant hypotension, midodrine, pyridostigmine, and droxidopa may be helpful in preventing OH.

CONCLUSION

The etiology and severity of autonomic dysfunction vary widely between patients, suggesting a need for an individualized treatment approach. Achieving perfect blood pressure control is not a realistic goal. Rather, treatment should be aimed at improving the patient's quality of life and decreasing their risk of injury and organ damage.

Sympathetic and Sensory-Motor Nerves in Peripheral Small Arteries

Small arteries, which play important roles in controlling blood flow, blood pressure, and capillary pressure, are under nervous influence. Their innervation is predominantly sympathetic and sensory motor in nature, and while some arteries are densely innervated, others are only sparsely so. Innervation of small arteries is a key mechanism in regulating vascular resistance. In the second half of the previous century, the physiology and pharmacology of this innervation were very actively investigated. In the past 10-20 yr, the activity in this field was more limited. With this review we highlight what has been learned during recent years with respect to development of small arteries and their innervation, some aspects of excitation-release coupling, interaction between sympathetic and sensory-motor nerves, cross talk between endothelium and vascular nerves, and some aspects of their role in vascular inflammation and hypertension. We also highlight what remains to be investigated to further increase our understanding of this fundamental aspect of vascular physiology.

Paroxysmal Orthostatic Ventricular Tachycardia in a Patient With Supine Hypertension and Orthostatic Hypotension

Supine orthostatic hypertension with orthostatic hypotension is an autonomic dysfunction where the patients present with hypertension when supine and with decrease in blood pressure while bearing an upright posture. We report on a 74-year-old male who was admitted with dizziness and was found to have profound orthostatic hypotension with supine hypertension. The patient also developed orthostatic paroxysmal premature ventricular beats as well as nonsustained ventricular tachycardia. In this report, we attempt to present the possible mechanism of orthostatic ventricular tachycardia in our patient and the overview of the treatment strategies used in management of patients with supine hypertension and orthostatic hypotension.

Prevalence of Orthostatic Hypotension and the Distribution of Pressure Variation in the Longitudinal Study of Adult Health

Fundamento

A hipotensão ortostática (HO) tem sido negligenciada na clínica não havendo estudos sobre sua prevalência na população brasileira.

Objetivo

Determinar a prevalência de HO e a variação da pressão arterial (PA) após manobra postural no Estudo Longitudinal da Saúde do Adulto.

Métodos

No presente estudo descritivo da linha de base (N = 14.833 indivíduos, 35-74 anos), os participantes ficavam deitados por 20 minutos e então levantavam ativamente, com a medida da PA em supino e aos 2, 3, e 5 minutos de ortostase. A HO foi definida por queda ≥ 20 mmHg na PA sistólica e/ou queda ≥ 10 mmHg na PA diastólica aos 3 minutos, sendo determinada a sua prevalência com intervalo de confiança de 95% (IC_95%). A distribuição da variação da PA após a manobra postural foi determinada numa subamostra (N = 8.011) após remoção de participantes com morbidade cardiovascular e/ou diabetes.

Resultados

A prevalência de HO foi de 2,0% (IC_95%: 1,8 – 2,3), crescente com a idade. Se o critério for a mesma queda pressórica em qualquer das medidas, a prevalência aumenta para 4,3% (IC_95%: 4,0 – 4,7). Em presença de HO houve relato de sintomas (tontura, escotomas, náuseas, etc.) em 19,7% dos participantes (IC_95%: 15,6 – 24,6) e em apenas 1,4% (IC_95%: 1,2 – 1,6) dos sem HO. Os escores-Z −2 das variações da PA antes e após manobra postural na subamostra foram de −14,1 mmHg na PA sistólica e −5,4 mmHg na diastólica.

Conclusão

A prevalência de HO varia em função do momento da aferição da PA. Os pontos de corte atuais podem subestimar a ocorrência de HO na população. (Arq Bras Cardiol. 2020; 114(6):1040-1048)

Orthostatic hypotension: clinical review and case study

Transient loss of consciousness (TLOC) accounts for 3% of all attendance in emergency departments within the UK. More than 90% of TLOC presentations are due to epileptic seizures, psychogenic seizures or syncope. However, in England and Wales in 2002, it was estimated that 92 000 patients were incorrectly diagnosed with epilepsy, at an additional annual cost to the NHS of up to £189 million. This article will reflect on the case study of a 54-year-old female patient who presented with a possible TLOC, and had a background of long-term depression. Differential diagnoses will be discussed, but the article will focus on orthostatic hypotension. Being diagnosed with this condition is independently associated with an increased risk of all-cause mortality. Causes of orthostatic hypotension and the pathophysiology behind the condition will be discussed, highlighting the importance of obtaining an accurate clinical history. This is extremely pertinent if a patient collapses in an NHS setting and this is witnessed by nurses because they can contribute to the history of the type of collapse, to aid diagnosis and correct treatment. In addition, nurses have a valuable role to play in highlighting polypharmacy to doctors, and non-medical prescribers, as a contributing factor to orthostatic hypotension is polypharmacy. It is therefore important to accurately distinguish TLOC aetiology, not only to provide appropriate management, but to also identify patients at risk of morbidity/mortality related to underlying disease.

Orthostatic hypotension following deep brain stimulation in parkinson's disease: a systematic review

Background: Deep brain stimulation (DBS) is a treatment that may be suitable for patients with Parkinson's disease (PD) with severe motor fluctuations and/or dyskinesias despite optimised medical therapy. DBS has been associated with side effects including deterioration in cognition, verbal fluency and mood. Studies assessing the effect of DBS on orthostatic hypotension (OH) have produced variable results.Objectives: The aim is to summarise peer-reviewed studies that have assessed the effect of DBS on systolic or diastolic BP in PD patients.Methods: The databases PubMed, EMBASE, Medline and Scopus were searched using the terms (Deep brain stimulation OR DBS) AND (hypotension OR hypertension OR blood pressure) on 13 April 2017.Results: Fourteen studies fulfilled the inclusion criteria. Ten studies involved subthalamic nucleus (STN) DBS, three studies globus pallidus interna (GPi) DBS and one study involved DBS of the pedunculopontine nuclei and motor thalamus. The majority of the studies found results indicating that DBS in PD does not worsen OH in PD.Conclusions: Small sample sizes and lack of blinding of outcome assessors means this result should be approached cautiously. Future research may further investigate the effect of GPi DBS on OH and should aim to address these methodological issues.

Syndrome of Supine Hypertension with Orthostatic Hypotension: Pathophysiology and Clinical Approach

This article is intended to provide guidance and clinical considerations for physicians managing patients suffering from supine hypertension with orthostatic hypotension, referred to as “SH-OH”. We review the normal physiologic response to orthostasis, focusing on the appropriate changes to autonomic output in this state. Autonomic failure is discussed with a generalized overview of the disease and examination of specific syndromes that help shed light on the pathophysiology of SH-OH. The goal of this review is to provide a better framework for clinical evaluation of these patients, review treatment options, and ultimately work toward achieving a better quality of life for patients afflicted with this disease.

Autonomic dysfunction: Diagnosis and management

The autonomic nervous system is designed to maintain physiologic homeostasis. Its widespread connections make it vulnerable to disruption by many disease processes including primary etiologies such as Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, and pure autonomic failure and secondary etiologies such as diabetes mellitus, amyloidosis, and immune-mediated illnesses. The result is numerous symptoms involving the cardiovascular, gastrointestinal, and urogenital systems. Patients with autonomic dysfunction (AUD) often have peripheral and/or cardiac denervation leading to impairment of the baroreflex, which is known to play a major role in determining hemodynamic outcome during orthostatic stress and low cardiac output states. Heart rate and plasma norepinephrine responses to orthostatic stress are helpful in diagnosing impairment of the baroreflex in patients with orthostatic hypotension (OH) and suspected AUD. Similarly, cardiac sympathetic denervation diagnosed with MIBG scintigraphy or ¹⁸F-DA PET scanning has also been shown to be helpful in distinguishing preganglionic from postganglionic involvement and in diagnosing early stages of neurodegenerative diseases. In this chapter, we review the causes of AUD, the pathophysiology and resulting cardiovascular manifestations with emphasis on the diagnosis and treatment of OH.

The response of the vestibulosympathetic reflex to linear acceleration in the rat

The vestibulosympathetic reflex (VSR) increases blood pressure (BP) upon arising to maintain blood flow to the brain. The optimal directions of VSR activation and whether changes in heart rate (HR) are associated with changes in BP are still not clear. We used manually activated pulses and oscillatory linear accelerations of 0.2-2.5 g along the naso-occipital, interaural, and dorsoventral axes in isoflurane-anesthetized, male Long-Evans rats. BP and HR were recorded with an intra-aortic sensor and acceleration with a three-dimensional accelerometer. Linear regressions of BP changes in accelerations along the upward, downward, and forward axes had slopes of ≈3-6 mmHg · g-1 (P < 0.05). Lateral and backward accelerations did not produce consistent changes in BP. Thus upward, downward, and forward translations were the directions that significantly altered BP. HR was unaffected by these translations. The VSR sensitivity to oscillatory forward-backward translations was ≈6-10 mmHg · g-1 at frequencies of ≈0.1 Hz (0.2 g), decreasing to zero at frequencies above 2 Hz (1.8 g). Upward, 70° tilts of an alert rat increased BP by 9 mmHg · g-1 without changes in HR, indicating that anesthesia had not reduced the VSR sensitivity. The similarity in BP induced in alert and anesthetized rats indicates that the VSR is relatively insensitive to levels of alertness and that the VSR is likely to cause changes in BP through modification of peripheral vascular resistance. Thus the VSR, which is directed toward the cardiovascular system, is in contrast to the responses in the alert state that can produce sweating, alterations in BP and HR, and motion sickness.

Prevalence of and factors related to mild and substantial dizziness in community-dwelling older adults: a cross-sectional study

Background

Dizziness is highly prevalent among older people and associated with many health factors. The aim of the study was to determine the prevalence of and factors related to dizziness among community-dwelling older adults in Sweden. In contrast to previous studies, the subjects with dizziness were divided into two groups, mild and substantial dizziness, according to the frequency and intensity of dizziness.

Methods

A sample of 305 older persons between 75 and 90 years of age (mean age 81 years) were interviewed and examined. Subjects with dizziness answered the University of California Los Angeles Dizziness Questionnaire and questions about provoking movements. The groups with substantial, mild, or no dizziness were compared with regard to age, sex, diseases, drugs, blood pressure, physical activity, exercises, falls, fear of falling, quality of life, general health, mobility aids, and physical performance.

Results

In this sample, 79 subjects experienced substantial and 46 mild dizziness. Subjects with substantial dizziness were less physically active, reported more fear of falling, falls, depression/anxiety, diabetes, stroke/TIA, heart disease, a higher total number of drugs and antihypertensive drugs, lower quality of life and general health, and performed worse physically.

Conclusions

There are many and complex associations between dizziness and factors like falls, diseases, drugs, physical performance, and activity. For most of these factors, the associations are stronger in subjects with substantial dizziness compared with subjects with mild or no dizziness; therefore, it is relevant to differ between mild and substantial dizziness symptoms in research and clinical practice in the future.

First Fall-Related Injuries Requiring Hospitalization Increase the Risk of Recurrent Injurious Falls: A Nationwide Cohort Study in Taiwan

Objectives

Recurrent falls not only have risk factors different from those of single falls but also have less favorable outcomes. The aim of our study was to determine the association between the injury characteristics of a first fall and the likelihood of recurrent injurious falls in a cohort of hospitalized patients.

Methods

We designed a nationwide retrospective cohort study and selected hospitalized patients who had injurious falls between 2001 and 2010. Cox proportional hazards models were used to estimate the hazard ratios (HRs) of recurrent injurious falls requiring hospitalization in the following year on the basis of the patients’ demographic characteristics, comorbidities, and the characteristics of injuries from the first injurious fall requiring hospitalization.

Results

Among the 504 512 patients hospitalized for injurious falls, 19 442 experienced recurrent injurious falls requiring hospitalization. The 1-year incidence of recurrent injurious falls requiring hospitalization was 3.85%. The incidence density was the highest within the 3-month period after the first injurious fall. The risk of recurrent injurious falls among patients aged 40 to 64, 65 to 74, and ≥ 75 years increased progressively (HR: 2.11, 95% confidence interval [CI]: 1.90–2.34; HR: 2.80, 95% CI: 2.51–3.11; and HR: 3.80, 95% CI: 3.42–4.23, respectively). The length of hospitalization (LOH) ≥ 15 or ≥ 31 days (HR: 1.39, 95% CI: 1.30–1.48; and HR: 1.59, 95% CI: 1.43–1.77, respectively) and injury to the head (HR: 1.59, 95% CI: 1.53–1.65) or spine (HR: 1.66, 95% CI: 1.59–1.74) were also found to be major risk factors.

Conclusions

Our findings show that the LOH and head and spine injuries are associated with an increased risk of recurrent injurious falls leading to hospitalization. The risk of recurrent injurious falls requiring hospitalization increased significantly among adults older than 40 years. We suggest further research on the effects of injury characteristics associated with the first injurious fall requiring hospitalization and resultant anatomical damages on the risk of recurrent injurious falls requiring hospitalization. High-risk patients should receive tailored rehabilitation addressing their respective injuries within 3 months after hospital discharge.