Chapter 9 Autonomic Dysreflexia and Emergencies 9 in Neurogenic Bladder B. Wefer, K.-P. Jünemann

soconstriction below the neurologic lesion and causing 9.1 Autonomic Dysreflexia 101 9.1.1 Epidemiology, Pathophysiology, and Clinical a rise in blood pressure. In neurologically intact per- Features 101 sons, higher centers inhibit these sympathetic effects 9.1.2 Etiology 101 by a compensatory vasodilatation of the splanchnic 9.1.3 Treatment 102 bed, resulting in normalized blood pressure. 9.2 Neurogenic Bladder and Spinal 103 In SCI patients, these higher inhibitory pathways are References 103 not intact and cannot reach the splanchnic bed, result- ing in high blood pressure. As a parasympathetic re- flex, the heart beat is also reduced (). 9.1 Typical clinical signs and symptoms are: Autonomic Dysreflexia ) Sudden severe ) Bradycardia ( is also possible) Autonomic dysreflexia is an acute syndrome character- ) Severe pounding headache ized by abrupt onset of excessively high blood pressure ) Flushed (reddened) face caused by uncontrolled sympathetic nervous system ) Paresthesia neck, shoulder, and arms discharge in patients with (SCI). Au- ) tonomic dysreflexia is potentially life-threatening. ) Blurred vision The syndrome was first described by Head and Rid- ) Tightness in chest doch in 1917 (Head and Riddoch 1917). In 1947, Gutt- ) Nausea mann and Whitteridge showed the effects of bladder ) Feeling of anxiety and agitation distensions on the cardiovascular system (Guttmann ) Arrhythmia and Whitteridge 1947). Autonomic dysreflexia is also ) Bladder and bowel contraction known as autonomic , paroxysmal neuro- ) Penile erection genic hypertension, sympathetic hyperreflexia, and ) Sweating and red blotches above the level of spinal neurovegetative syndrome. cord injury ) Piloerection () and cold, clammy skin 9.1.1 below the level of spinal cord injury Epidemiology, Pathophysiology, and Clinical Features It is important to note that the resting blood pressure The frequency of autonomic dysreflexia varies widely, decreases after a spinal cord injury. Often a blood pres- but appears to be relatively common in spinal cord-in- sure of 90/60 mmHg is normal for SCI patients and this juredpatientswithalesionatorabovethesixththorac- means that even a normal blood pressure of 120/ ic neurologic level (T6). Sometimes autonomic dysref- 80 mmHg might be considered increased. If possible, lexia is also seen in paraplegic patients with lesions be- SCI patients should be asked for their normal resting low T6, but usually the clinical presentation is milder. blood pressure. Lifetime frequency of autonomic dysreflexia is between 19% and 85% (Snow et al. 1978; Braddom and Rocco 9.1.2 1991; Shergill et al. 2004). In particular, patients with Etiology cervical lesions (60%) show autonomic dysreflexia compared to patients with thoracic lesions (20%). Almost any precipitant below the neurologic lesion can In healthy persons, an afferent stimulus enters the trigger autonomic dysreflexia. Important to the urolo- spinal cord and then ascends to the brain. Some inter- gist, a genitourinary cause is responsible in 81%–87% neurons are reflexively connected with preganglionic of cases (Shergill et al. 2004). The commonest reason sympathetic neurons and excite them, resulting in va- for autonomic dysreflexia is bladder distension, ac- 102 9 Autonomic Dysreflexia and Emergencies in Neurogenic Bladder

counting for 75%–85% of cases (Blackmer 2003). 9.1.3 Bladder distension can be a consequence of a kinked or Treatment obstructed catheter as well as an insufficient intermit- tent catheterization frequency. Other urinary triggers Acute management of autonomic dysreflexia is impor- are infection, instrumentation, stones, and urethral tant to prevent complications. If untreated autonomic distension. dysreflexia can lead to convulsions, subarachnoid hem- As almost 90% of cases have a genitourinary cause, orrhage, intracerebral , hypertensive encepha- it is particularly important for the urologist to prevent lopathy, cardiac arrhythmias, neurogenic pulmonary autonomic dysreflexia. When treating patients with edema and death (Shergill et al. 2004). SCI, the urologist should be aware of the possibility of The acute management aims to relieve the precipi- autonomic dysreflexia. When performing instrumen- tant cause and management of symptoms to prevent tation of the lower urinary tract, for example changing potential complications. The long-term goal is to pre- a catheter, local anesthetic jelly and an aseptic tech- vent recurrence of autonomic dysreflexia. nique (to avoid urinary tract infection as a precipitant Immediately the precipitant should be identified ofautonomicdysreflexia)shouldbeused.Iftheinstru- and treated. mentation takes more than a few minutes (, To prevent a further increase in blood pressure, the urodynamic investigation) sufficient blood pressure patient should be seated upright with the head raised to monitoring should also be provided. It should also be induce an orthostatic drop in blood pressure. Tight notedthatevensexualintercoursecaneffectautonomic clothing should be removed and during treatment the dysreflexia. Therefore the andrologist should keep in blood pressure should be monitored carefully (every mind this risk when applying vibroejaculation to a SCI 2–5min). patient. Then the trigger for autonomic dysreflexia should The second most common precipitant for autonom- be identified and eliminated. In most cases, a genitouri- ic dysreflexia is bowel distension (13%–19% of cases). nary problem is the precipitant. Therefore, if the pa- Table 9.1 displays precipitants for autonomic dysref- tient has an indwelling catheter the catheter should be lexia. checked for kinks and obstructions. In addition, a full urinary bag can cause bladder distension leading to au- tonomic dysreflexia. If necessary, the catheter should Table 9.1. Precipitants for autonomic dysreflexia be carefully flushed with saline solution. Irrigation should be limited to 5–10 ml in children under 2 years Urological Bladder distension (kinked/obstructed catheter) Infection and 10–15 ml in children older than 2 years and adults. Urethral distension If no indwelling catheter is placed but bladder disten- Instrumentation (indwelling catheter, cystos- sion is the suspected trigger, a catheter should be insert- copy, urodynamics) ed.Beforeinsertingthecatheter,theurethrashouldbe Stones Ejaculation (vibro- or electroejaculation) instilled with lidocaine jelly to avoid further triggers for Sexual intercourse autonomic dysreflexia. In many cases, draining the blad- der alleviates the symptoms of autonomic dysreflexia. Gastro- Bowel distension (fecal impaction) intestinal Instrumentation If afferent stimulation of bladder wall receptors (in- Infection or inflammation (colitis, peritonitis) fection, stones) is supporting the autonomic dysrefle- Gastric ulcer xia, local anesthetic (lidocaine) instillation of the blad- Reflux der might be effective (Dietz 1996). Anal fissure High-dose antibiotics are delivered if urinary tract infection is suspected to be the cause. If symptoms per- Dermato- Pressure sore logic Ingrown toenail sist other triggers must be sought. Burns (sunburns, burns from hot water) Thenextstepisarectalexaminationforfecalimpac- Tight clothing or pressure to skin tion and a gentle manual evacuation if necessary. Skeletal Heterotopic ossification If the precipitant for autonomic dysreflexia is not Fracture found within the first few minutes medical treatment is Joint dislocation necessary when the blood pressure remains high. Repro- Labor and delivery There are only a few published studies on medical ductive Menstruation treatment of autonomic dysreflexia, but and Test icular torsion nitrates are the most commonly used drugs. The imme- Hemato- Deep vein thrombosis diate release form is the preferred method of adminis- logic Pulmonary embolism tration. Nifedipineisgiveninadoseof10mgusingthebite- and-swallow method. Adverse effects of nifedipine References 103 have been reported (reflex tachycardia and hypoten- ously. Usually indwelling catheters are used. A better sion), but in these studies nifedipine was not used to approach is a suprapubic catheter, especially in men, to treat autonomic dysreflexia (Consortium for Spinal prevent the patient from urethral trauma and prostatic Cord Medicine 2001). infections. Nitrates (glyceryl trinitrate, isosorbide dinitrate, so- After the polyuria phase, the patient should start diumnitroprusside)arealsousedtotreatautonomic with an intermittent catheterization program (if possi- dysreflexia. If the blood pressure remains high an intra- ble dependent on neurologic lesion and hand function) venous drip of sodium nitroprusside could be neces- (Dietz 1996). sary. Before using these drugs (nitrates), the patient When the phase ends, bladder dysfunc- should be questioned regarding sildenafil or other tion will develop and a urodynamic investigation is PDE-5 inhibitors. If a PDE-5 inhibitor was used in the needed to treat the dysfunction properly. last 24 h an alternative short-acting, rapid-onset anti- Bladderrehabilitationshouldbeapartoftheoverall hypertensive drug should be used. Drugs with these rehabilitation routine after spinal cord injury and characteristics are captopril and prazosin. should be adjusted to the result of the urodynamic inves- Other drugs that have been used to treat autonomic tigation. dysreflexia include hydralazine, phenoxybenzamine, , diazoxide, and (Consortium for Spinal Cord Medicine 2001; Blackmer 2003). References With recurrent episodes of autonomic dysreflexia, prevention is the best approach. Therefore patients Blackmer J (2003) Rehabilitation medicine: autonomic dysref- with spinal cord injury and their families should be ed- lexia. CMAJ 28:169:931 ucated about proper bladder, bowel, and skin manage- Braddom RL, RJ (1991) Autonomic dysreflexia. A survey of current treatment. Am J Phys Med Rehabil 70:234 ment. If a catheter is present it should be changed regu- Consortium for Spinal Cord Medicine (2001) Acute manage- larly with great care and attention to avoid autonomic ment of autonomic dysreflexia: individuals with spinal cord dysreflexia, ideally using local anesthetic jelly. Urody- injury presenting to health care facilities. Washington, DC, namicinvestigationsshouldbedonewithbloodpres- The Consortium of Paralyzed Veterans of America Dietz (1996) Querschnittslähmung: Physiopathologie Klinik sure monitoring in SCI patients. Other colleagues und Therapie von Blasenfunktion Bewegung und Vegetati- should be made aware of the propensity for autonomic vum. Kohlhammer, Stuttgart dysreflexia in affected patients. Guttmann L, Whitteridge D (1947) Effects of bladder disten- sion on automatic mechanisms after spinal cord injury. Brain 70:361 Head H, Riddoch G (1917) The autonomic bladder, excessive 9.2 sweating and some other reflex conditions in gross injuries Neurogenic Bladder and Spinal Shock of the spinal cord. Brain 40:188 Shergill IS, Arya M, Hamid R, Khastgir J, Patel HR, Shah PJ Directly after the spinal cord injury, all reflexes below (2004) The importance of autonomic dysreflexia to the urol- the neurologic lesion have disappeared. This is called ogist. BJU Int. 93:923 Snow JC, SH, Kripke BJ, Freed MM, Shah NK, Schlesinger RM spinal shock. In this phase, the bladder is hypotonic. (1978) Autonomic hyperreflexia during cystoscopy in pa- This phase takes normally 4–6 weeks, sometimes up to tients with high spinal cord injuries. Paraplegia 15:327 6–8months. To prevent the bladder from overdistension (due to polyuria), it is important to drain the urine continu-