Antidiuretic hormone levels and polyuria in spinal cord injury. A preliminary report

Conservative Bladder Management and Medical Treatment in Chronic Spinal Cord Injury Patients

To review the available data on non-surgical management for neurogenic lower urinary tract dysfunction (NLUTD) in patients with chronic spinal cord injury (SCI) and provide the most updated knowledge for readers. We categorized the bladder management approaches into storage and voiding dysfunction separately; both are minimally invasive, safe, and efficacious procedures. The main goals for NLUTD management are to achieve urinary continence; improve quality of life; prevent urinary tract infections and, last but not least, preserve upper urinary tract function. Annual renal sonography workups and regular video urodynamics examinations are crucial for early detection and further urological management. Despite the extensive data on NLUTD, there are still relatively few novel publications and there is a lack of high-quality evidence. There is a paucity of new minimally invasive and prolonged efficacy treatments for NLUTD, and a partnership between urologists, nephrologists and physiatrists is required to promote and ensure the health of SCI patients in the future.

Renal and Endocrine Responses to Arm Exercise in Persons with Cervical Spinal Cord Injury

The aim of this study was to assess renal functions and endocrine responses to arm exercise in persons with cervical spinal cord injury (CSCI) under euhydrated conditions (free drinking of water), and to determine the physiological effects of exercise on renal function in these subjects. Eleven CSCI individuals (spinal lesions between C6 and C8, American Spinal Injury Association impairment scale A) and nine able-bodied (AB) persons rested for 30 min before performing 30 min arm-crank ergometer exercises at 50% of their maximum oxygen consumption, followed by 60-min of rest/recovery. Urine and blood samples were collected before and immediately after the exercise and recovery period. The CSCI patients showed no increase in plasma adrenaline and plasma renin activity compared with the AB controls, but showed similar changes in plasma aldosterone and the plasma antidiuretic hormone in response to the exercise. Creatinine clearance, osmolal clearance, free water clearance, and the fractional excretion of Na⁺ did not change during exercise in both groups of subjects, however free water clearance in the CSCI group was higher than in the AB group throughout the study. These findings suggested that activated plasma aldosterone without an increase in adrenaline or renin activity during exercise in CSCI individuals may reflect an adaptation to the disturbance of the sympathetic nervous system to compensate for renal function. As a result, no adverse effects of exercise on renal function in CSCI patients were observed.

Timeline of Changes in Biomarkers Associated with Spinal Cord Injury-Induced Polyuria

Deficits in upper and lower urinary tract function, which include detrusor overactivity, urinary incontinence, detrusor-sphincter dyssynergia, and polyuria, are among the leading issues that arise after spinal cord injury (SCI) affecting quality of life. Given that overproduction of urine (polyuria) has been shown to be associated with an imbalance in key regulators of body fluid homeostasis, the current study examined the timing of changes in levels of various relevant hormones, peptides, receptors, and channels post-contusion injury in adult male Wistar rats. The results show significant up- or downregulation at various time points, beginning at 7 days post-injury, in levels of urinary atrial natriuretic peptide, serum arginine vasopressin (AVP), kidney natriuretic peptide receptor-A, kidney vasopressin-2 receptor, kidney aquaporin-2 channels, and kidney epithelial sodium channels (β- and γ-, but not α-, subunits). The number of AVP-labeled neurons in the hypothalamus (supraoptic and -chiasmatic, but not paraventricular, nuclei) was also significantly altered at one or more time points. These data show significant fluctuations in key biomarkers involved in body fluid homeostasis during the post-SCI secondary injury phase, suggesting that therapeutic interventions (e.g., desmopressin, a synthetic analogue of AVP) should be considered early post-SCI.

Medical management of neurogenic bladder with oral therapy

This is a review of the most current literature on medical management of the neurogenic bladder (NGB) to treat detrusor overactivity (DO), improve bladder compliance and treat urinary incontinence. The use of antimuscarinics, alpha blockers, tricyclic antidepressants, desmopressin and mirabegron will be discussed along with combination therapy to improve efficacy. These medical therapies will be the focus of this review with surgical therapy and botulinum toxin injections being the subject of other articles in this series.

The epidemiological survey of acute traumatic spinal cord injury (ATSCI) of 2002 in Beijing municipality

STUDY DESIGN

Epidemiological survey.

OBJECTIVES

To study the incidence and epidemiology of acute traumatic spinal cord injury (ATSCI) of 2002 in Beijing municipality.

SETTING

Beijing.

METHODS

After quota sampling, data of all ATSCI patients who were injured in Beijing in 2002 from sample hospitals were collected for detailed investigation.

RESULTS

In all, 1079 patients were estimated to have ATSCI in 2002 in Beijing municipality and the annual incidence was 60.6 per million. The incidence increased more than ninefold compared with that of 6.7 per million between 1982 and 1986. The mean age of patients at the time of injury was 41 years. The male/female ratio was 3.1/1. The causes of injury were fall from height (37.5%), traffic accidents (26.9%), struck by object (16.3%) and fall on ground (8.3%), in that order. The mean expenditure of hospitalisation was 27819.3 RMB in 2002. The proportion of cervical, thoracic and lumbar injuries was 4.9, 28.0 and 65.9, respectively in 2002. The mean time of hospitalisation was 18.9 days and only 1.5% of the spinal cord injury (SCI) patients went to rehabilitation hospitals after their discharge. The severity of neurological impairment was not recorded in the majority of hospitals.

CONCLUSION

There was a rapid increase of the annual SCI incidence from 1982 to 2002 during an economic boom. Safety regulations are of primary importance in preventing the injury. Once happened, long-term health insurance is essential for the well-being of the victims. Although some improvement has been made since 2002, much remains to be done in this direction.

Nocturnal polyuria with abnormal circadian rhythm of plasma arginine vasopressin in post-stroke patients

OBJECTIVE

Nocturia is a common reason for interrupted sleep in post-stroke patients. These patients often have neurogenic bladder overactivity. However, little is known about the possible contribution of nocturnal polyuria in the patients.

METHODS

We measured the number of nocturia, the circadian plasma arginine vasopressin (AVP) level and urinary excretion in 4 patients with stroke.

RESULTS

All patients had nocturnal urinary frequency (three times in one and twice in 3). All patients were revealed to have nocturnal polyuria, and the ratio of nocturnal urinary output to 24 hour volume ranged from 36% to 63%. Measurement of daily plasma AVP variation showed that all patients lost normal nocturnal rise of the plasma AVP concentration. Two patients were successfully treated with 5 mug of intranasal desmopressin once a night, a potent analogue of AVP, without hypertension particularly in the night, signs of congestive cardiac failure or any electrolyte abnormality such as hyponatremia.

CONCLUSION

Our post-stroke patients had nocturnal polyuria with abnormal circadian rhythm of plasma AVP secretion. Desmopressin reduced nocturnal waking in urination. It also ameliorated nocturnal dehydration that might trigger a stroke recurrence in the patients.

Nocturnal polyuria and antidiuretic hormone levels in spinal cord injury

OBJECTIVE

To establish baseline ADH levels in spinal cord injury patients and to evaluate whether spinal cord patients have attenuation of diurnal variation of ADH similar to children with enuresis and elderly with nocturnal polyuria.

DESIGN

Twenty-seven healthy quadriplegic patients, ASIA impairment scale A, were evaluated for serum ADH levels at night and during the day.

MAIN OUTCOME MEASURES

Evaluation of whether bladder overdistention caused by attenuation of diurnal variation of ADH is responsible for the episodes of autonomic dysreflexia and recurrent urinary tract infections in spinal cord injury patients who are on intermittent catheterization for bladder management.

RESULTS

A lack of diurnal variation of ADH in the subject population.

CONCLUSIONS

A trial of desaminocystein-D-arginine vasopressin (DDAVP) should be considered for patients with established attenuation of the diurnal variation ADH.