Micturition Syncope

0022-5247 /81/1264-0551$02.00/0

Tmc

Vol. 126, Octobe,-

JOURNAL OF UROLOGY

Coi;y:right © 1981 by The Williams & Wilkins Co.

Printed in U. S.A

SYNCOPE C. ~T. GODEC''' lJrotn the

AND

A. S. CASS

of Surgery, Division of Urology, Hennepin Medical Center, 1v11cru,ieu,µu•u::; and Ramsey Hospital, St. Paul, Minnesota

ABSTRACT

event. Increased vagal stimulation and standing position factors of this syndrome. Postural may V•'P""" the predominance of male victims. example and an unusual incident in a woman. m,nvF,H,o...a.

or follow-

Gastaut and Fischer--1Nilliams described 2 types of syncopeimmediate and "'"'"''-'Pn I ocular compression bifor 10 to 15 seconds. HL.UHCU>m,C

and even cardiac arrest. It that nausea, vu""'''"'" and decrease in blood pressure. It is of~µ·vuca,,c,,u~syncope cardiac arrest of the aucvuv1rn,c innervation the target organ is part in micturition an imbalance in autonomic .i.nnervation with could ~"'~.w~ a strong CASE REPORTS

area of examination the anne,arect normal_ ex-· re,;tneSJ.a in the neck. Pulse and blood pressure ec1;rocaira1o~rarnand of refused ation. Two years after the incident the was free ":;;:";:::tc,,""·s. No occurrence of syncope has occurred the ur10

woman was seen for stress incontinence and nocturnal enuresis. IVIedical revealed bilateral ureuu ,m,ca.u·c,u with reflux into both segments and lower for which the had m,-i,,,·,n,,n bilateral hemi-

gram, voiding cystourethrogram and cystoscopy were norm.al in view of the medical history. A urine culture was The urodynamic diagnostic study included a supine cystometrogram. The supine cystometrogram was normal, a capacity of 680 cc. During bladder filling for a cystometrogram, with the patient in the standing position, she collapsed when the bladder reached a capacity of 450 cc (see figure). After 3 minutes in the supine position the patient regained consciousness and was feeling well. She denied episode of syncope and had no history of cular disease. COMMENT

Micturition syncope is a complex neurovascular phenomenon that is not understood completely. Because of the of this type of event there is little agreement on the parameters involved. Our first patient had the classic description of the Qmnr'""'"'" The complete absence of any detectable abnormality c,nn"'".,.." to support the idea that micturition syncope represents transient disturbance of normal physiological functions m healthy individuals and is not the result of some structural disease. The second case is more interesting because micturition syncope is extremely rare in female patients. In some authors believe that it does not occur. 3 Since most cases occuT with the patient in the standing position it is µv,,N,use that women are protected by their seated voiding posture. When the woman in our case fainted during bladder filling, the reverse of the voiding maneuver, she was standing. Sudden bladder (150 cc per minute) could represent a massive sensory from the bladder to the vagal center. The combination of position and rapid bladder distension had an tant role in triggering micturition syncope in this case. The uxodynamic findings were nonspecific and did not this occurrence of micturition syncope. Valsalva maneuver frequently is cited as a factor in micturition syncope. If micturition is associated straining this may trigger V alsalva's maneuver with increased intrathoracic, intra-abdominal and intra.cerebral and subsequent diminished venous return. to the heart. ;,.,..,._,,r1t,,t and Forteza postulated that the circulatory effects of Valsalva's maneuver, at the moment when the venous retuTn to the heart and the peripheral resistance are low, might be the causeo 4 Eberhart and Morgan add that functional vesical neck obstruction may be the induction factor for Valsalva's maneuver which, in conjunction with straining, may result in syncope. 5 Many reports on micturition syncope are related to Pickering noted that blood pressure decreases pr,otcmr1CU sleep: in l case from 135 to 65 mm. Hg, no change in heart rate. 6 Under normal waking conditions, when one 551

552

GODEC AND CASS

UPP (cmH 20)

~gt 0

CMG SUPINE PRESSURE (cmH 20) CMG STANDING PRESSURE (cm H20l

' ;s:J

10

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20 30 LENGTH (cm)

40

50

~I

40

,;r-Potient fainted

30 20 10 0

UROFLOW (cc)

150

300 450 600 VOLUME (cc)

750

50 40 30 20 10 0

be the effect of loss of pressure on the distended bladder. Sudden decompression of a distended bladder by catheterization can result in severe circulatory collapse. 7 Exaggerated lordotic posture, assumed by some during voiding, also may interfere with venous return. 8 Howarth and associates suggest that diminished venous return reduces filling pressure and triggers impulses from the heart to the central nervous system, initiating the vasovagal fainting reflex and resulting in syncope. 9 Micturition syncope probably is not caused by any single entity but by a complex of factors. Recovery generally is rapid and complete, recurrences are rare and the results of physical examinations, including electrocardiogram and electroencephalogram, usually are normal. We probably should consider this disorder to be a transient disturbance of normal physiological functions in healthy individuals, rather than the result of some underlying structural disease. If the case history is unremarkable an intensive search for organic pathology usually is unrewarding. REFERENCES 1.

Gastaut, H. and Fischer-Williams, M.: Electro-encephalographic study of syncope. Its differentiation from epilepsy. Lancet, 2: 1018, 1957.

5

10 15 TIME (sec)

20

25

Urodynamic evaluation, including urethral pressure profile ( UPP), cystometrogram ( CMG) in supine and standing positions, and uroflow, display nonspecific findings. from a recumbent to an erect posture, baroreceptors cause peripheral vasoconstriction, an increase in heart rate, and venous tone and contraction of the leg muscles. During sleep the function of these baroreceptors may be decreased or the response to afferent stimuli may be inadequate. A strong vagal stimulus, produced by the act of micturition, could further decrease the already low pressure. Thus, postural hypotension could explain why micturition syncope occurs most frequently in patients who had been sleeping. Since men generally stand while voiding this theory would also explain the predominance of male patients with this syndrome. Another possible explanation for micturition syncope could

2. Engel, G. L., Romano, J. and McLin, T. R.: Vasodepressor and carotid sinus syncope; clinical, electroencephalographic and electrocardiographic observations. Arch. Intern. Med., 74: 100, 1944. 3. Donker, D. N., Robles de Medina, E. 0. and Kieft, J.: Micturition syncope. Electroenceph. Clin. Neurophysiol., 33: 328, 1972. 4. Proudfit, W. L. and Forteza, M. E.: Micturition syncope. New Engl. J. Med., 260: 328, 1959. 5. Eberhart, C. and Morgan, J. W.: Micturition syncope. Report of a case. J.A.M.A., 174: 2076, 1960. 6. Pickering, G.: Hyperpiesis: high blood-pressure without evident cause: essential hypertension. Brit. Med. J., 2: 929, 1965. 7. Shaw, E. C. and Young, H. H.: Gradual decompression in chronic vesical distension. Presentation of a decompressing manometer and automatic bladder irrigator. J. Urol., 11: 373, 1924. 8. Brigden, W., Howarth, S. and Sharpey-Schafer, E. P.: Postural changes in the peripheral blood-flow of normal subjects with observations on vasovagal fainting reactions as a result of tilting, the lordotic posture, pregnancy and spinal anaesthesia. Clin. Sci., 9: 79, 1950.

9. Howarth, S., McMichael, J. and Sharpey-Schafer, E. P.: Effect of venesection in low output heart failure. Clin. Sci., 6: 41, 1946.