Neurologic emergencies

This article considers the rapid assessment and initial management of several neurologic emergencies--altered consciousness, increased intracranial pressure, stroke, status epilepticus, acute neurogenic respiratory failure, acute autonomic instability, the neuroleptic malignant syndrome, and spinal cord compression.

Management of a pregnant paraplegic patient in a rehabilitation center

As the population of paraplegic women of child-bearing age increases, the psychiatrist may be more frequently called on to care for pregnant women. Pregnancy in a paraplegic patient can be accompanied by many serious medical problems including autonomic dysreflexia, anemia, decubitus ulcers, urinary tract infections, and premature labor. This is a case report of a successful pregnancy in a spinal cord injured woman who was managed at a rehabilitation center throughout her entire pregnancy, despite developing the multiple complications described above.

Preterm labor in the quadriplegic parturient

The occurrence of preterm labor is not uncommon in the pregnant quadriplegic. Early diagnosis is hampered by the inability of most quadriplegics to sense uterine contractions in the usual way. A patient we recently treated for preterm labor learned to recognize contractions by the associated symptoms of autonomic hyper-reflexia: flushing, headache, and piloerection. Tocolytic therapy was successful and a favorable neonatal outcome occurred. Increased awareness by the physician and the pregnant quadriplegic patient is encouraged so that symptoms of autonomic hyper-reflexia may be recognized as potentially indicative of uterine contractions.

Atrial demand pacing to protect against vagal overactivity in sympathetic autonomic neuropathy

The clinical features, investigation and management of a patient with a subacute autonomic neuropathy are described. A series of physiological and biochemical studies indicated severe but selective sympathetic cardiovascular dysfunction, associated with bradycardia. The bradycardia was enhanced by raising blood pressure but there was no other evidence either of cardiac vagal impairment or hyperreactivity. Oral atropine prevented the bradycardia but had to be withdrawn because of intolerable side effects. An atrial demand pacemaker was implanted to elevate basal heart rate and prevent bradycardia. The pacemaker alone did not improve postural hypotension but it enabled the blood pressure to be readily and safely controlled by a combination of drugs.

Autonomic dysfunction and Eaton Lambert syndrome

Autonomic dysfunction associated with Eaton Lambert syndrome in a patient with oat cell carcinoma of the lung is reported. Widespread postganglionic adrenergic and cholinergic defects suggested the presence of autonomic neuropathy. Clinical remission accompanied tumor regression after combined chemotherapy and radiation.

Autonomic hyperreflexia: a mortal danger for spinal cord-damaged women in labor

Reproductive care of women with spinal cord damage demands knowledge of such women's reproductive potential and the specific complications to which these women are prone during pregnancy and childbirth, especially autonomic hyperreflexia. Fertility in cord-damaged women of reproductive age is generally undiminished as are libido, ability to have intercourse, and ability to bear children. Frequent complications of cord-damaged pregnant women include urinary tract infection, anemia, pressure sores, sepsis, unattended birth, and autonomic hyperreflexia. Autonomic hyperreflexia or autonomic dysreflexia occurs during labor in up to two thirds of women with cord lesions above T-6. Autonomic hyperreflexia results from noxious stimuli including distention of the bladder, cervix, or rectum, which evokes mass triggering of sympathetic and parasympathetic afferents that are uninhibited by supraspinal centers below the cord lesion. Autonomic hyperreflexia manifests itself with sudden onset of marked hypertension and headache during uterine contractions, as well as bradycardia or tachycardia, various cardiac dysrhythmias, and marked diaphoresis with piloerection and flushing above the level of the cord lesion. We describe the second reported occurrence of intraventricular hemorrhage due to autonomic hyperreflexia during labor and detail recommendations for anticipating and mitigating this potentially lethal complication of parturition in cord-damaged women. Pregnancy and parturition are best carried out with informed cooperation of the patient and of obstetric, cord rehabilitation, anesthetic, and nursing personnel.

Blood pressure and vasopressin in progressive autonomic failure. Response to postural stimulation, L-dopa and naloxone

We showed previously that patients with progressive autonomic failure with multiple system atrophy (MSA) failed to excrete a water load while they were standing, suggesting abnormal postural regulation of vasopressin release. The rise of plasma arginine vasopressin (AVP) with upright posture is modulated by central dopamine and opioid receptors. Patients with MSA may have depletion of brain dopamine and opioid peptides. We measured the plasma levels of AVP in patients with MSA and control subjects during postural stimulation by head-up tilt and the inhibition of this rise in AVP by L-DOPA (dopamine precursor) and naloxone (opiate antagonist). Since L-DOPA and naxolone can alleviate hypotension, we also studied the effects of these agents on orthostatic hypotension. Plasma AVP concentration of normal subjects rose progressively over 90 min of head-up tilt and this postural rise in AVP was abolished by L-DOPA and naloxone. Patients with MSA had similar levels of AVP while horizontal. However, they showed a severely blunted postural AVP response since their levels rose to only 10 per cent of the rise in the normal subjects despite the additional stimulus to AVP secretion of considerable postural hypotension. They also showed no inhibition of AVP secretion by L-DOPA or naloxone. Naloxone did not alter the blood pressure of either group. Although L-DOPA did not change the blood pressure of normal subjects, it lowered it in patients with MSA both while they were horizontal and tilted.

IN CONCLUSION

(1) the postural stimulation of AVP release is blunted in MSA; (2) this postural rise in AVP is not inhibited by a dopamine agonist or opioid antagonist in MSA suggesting loss of dopaminergic and opioid pathways involved in AVP release; (3) endogenous opioids do not contribute to orthostatic hypotension in MSA; (4) patients with MSA are supersensitive to the hypotensive effects of an acute L-DOPA infusion.

Sympathetic neural prosthesis for managing orthostatic hypotension

A prototype electromechanical analogue of the sympathetic division of the baroreceptor reflex arc was used to maintain blood pressure automatically in two patients with neurogenic orthostatic hypotension. The device prevented significant and sustained reductions in mean blood pressure when the patients were tilted up to 85 degrees. Upon achieving the preset mean blood pressure, the device maintained this pressure with a standard error of less than 2 mm Hg. Similar results were obtained when the patients were walking. The device did not cause supine hypertension during the trials.

The Key-Gaskell syndrome: the current situation

During the past 12 months an apparently new disease of cats has occurred with increasing frequency throughout the United Kingdom causing high morbidity and mortality and arousing considerable interest both within and outside the profession. The purpose of this paper is to report what is known about the disease and to indicate lines of current research. As there is an urgent need to communicate information it will be appreciated that this paper is incomplete in certain areas such as pathology and epidemiology where studies are still in progress.