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to acute blockage of an indwelling catheter or large residual urine due to obstruction
at the external or internal sphincter complex or by a stone at any level of the
urinary tract which needs appropriate measures. Obstruction in the intestinal tract by
constipation may be another cause of these autonomous reflex responses. Neglect of
these manifestations of stress in the organism may sometimes elicit epileptic fits and, if
not counteracted early, may cause cerebral haemorrhage (see chapter of Pregnancy and
Labour). On the other hand, the awareness of some of these phenomena by the patient,
such as flushing, feeling of heat, sweating, etc., can be utilized for the patient's training
to employ adequate stimuli for emptying the bladder at regular intervals in accordance
with fluid intake.
B. THE AUTONOMOUS CONUS-CAUDA EQUINA
BLADDER (NUCLEAR-RADICULAR OR LOWER
MOTOR NEURON TYPE)
Destruction of the ganglion cells and their synapses within the spinal bladder centre
itself or its nerve roots, in complete lesions of the conus-cauda equina, results in inter
ruption of the connections between bladder and spinal vesical centre. The bladder has
become autonomous. Effective detrusor contractions do not occur and voiding depends
on the usually ineffective control of the autonomous intramural innervation of the
bladder wall which is incapable of provoking appropriate powerful emptying contrac
tions to bladder distension. Therefore, micturition is activated by abdominal pressure
and depends on the efficiency and power of the abdominal muscles. Cystometry shows
either a flat curve with feeble and irregular contractions or, in patients where the bladder
wall has become rigid, a greater or lesser steep slope of its tonus limb. There is dribbling
or stress incontinence, if the external urethral sphincter and the muscles of the pelvic
floor are de-efferentated, but the bladder can be emptied more or less satisfactorily by
manual pressure, assisted by abdominal pressure at regular intervals. There are exceptions
to this rule. One of our patients was admitted several months after cordectomy because of
an intramedullary tumour. The whole spinal cord with its roots below T9 had been
removed, yet cystometry revealed some moderate though irregular detrusor contractions
with considerable voiding effect. In this case, the autonomous intravesical innervations
had undoubtedly reached an unusual degree of compensatory function.
C. MIXED FORMS OF VESICAL DYSFUNCTION
In some cases of conus-cauda equina lesion or longitudinal lesions at higher level, the
destruction of the spinal bladder centre or its roots is only partial and there may be
various forms of dissociation in the paralysis of detrusor, external urethral sphincter
and pelvic floor muscles. This results in mixed forms of autonomous and automatic
bladder function. Provided the sacral arc has escaped total damage, greater or lesser
co-ordinated detrusor contractions may develop once the acute phase of bladder atonicity
