Biomedical subjects

J P Hanna

Publications and source records attributed to J P Hanna.

9 recordsLinked to original sources

PubMed2000

Parental attitudes toward BB and pellet guns.

As well as describing our pediatric BB and pellet gun injuries and the circumstances surrounding these injuries, we also evaluated parental perceptions of the dangers of BB and pellet guns. A convenience sample of three groups of parents and their children presenting to a Midwest, urban, children's hospital emergency department was prospectively enrolled. The three groups of parents included the injured group, which consisted of the parents whose children had been injured by BB or pellet guns; the gun group, which consisted of the parents who allowed their children to possess BB or pellet guns but had not sustained injury from these guns; and the no gun group, which consisted of the parents who did not allow their children to have these guns. All parents completed a survey concerning their attitudes toward BB and pellet guns. Twenty-eight parents completed questionnaires in each of the three groups. Most BB and pellet gun injuries occurred in adolescent males at home without adult supervision and were inflicted by a friend or by themselves. The injured group and the no gun group viewed BB and pellet guns as significantly more dangerous than the gun group. Parents who allow their children to have BB or pellet guns appear to misperceive their potential for injury by allowing their children to use these guns in an unsafe manner. Clinicians must educate parents about the significant potential for injury of nonpowdered guns.

Adolescent↗

PubMed1998

Rhabdomyolysis and hypoxia associated with prolonged propofol infusion in children.

Propofol, a new anesthetic, is now used more commonly to sedate patients in the intensive care unit. Propofol's rapid elimination has popularized its use to induce and maintain hypnosis in patients with refractory status epilepticus. It is also associated with occasional severe metabolic acidosis and hypoxia of indeterminate cause in children. We report a child and an adolescent who developed severe metabolic acidosis, progressive hypoxia, and rhabdomyolysis during maintenance infusion of propofol for the treatment of refractory status epilepticus. We suggest that propofol should not be used for prolonged sedation in children until its safety can be ensured.

Adolescent↗

PubMed1997

Intra-arterial thrombolysis of embolic proximal middle cerebral artery occlusion from presumed atrial myxoma.

The role of thrombolysis in brain ischemia in patients with atrial myxoma is unknown. A patient with acute brain ischemia and previously undiagnosed atrial myxoma recanalized an occluded middle cerebral artery with intra-arterial thrombolysis. Arterial occlusion from presumed myxoma may be amenable to fibrinolysis. Angiography before treatment in patients with atrial myxoma excludes a myxomatous pseudoaneurysm and permits site-specific thrombolytic instillment.

Carotid Arteries↗

PubMed1995

Automatic stepping in the pontomedullary stage of central herniation.

Both spontaneous and reflexive movements may occur during the final stages of herniation and following brain death. We describe spontaneous, rhythmic (0.2 to 0.5 Hz), alternating flexion of the hip, knee, and ankle in two patients during the pontomedullary phase of central herniation following a massive hemispheric infarct. Automatic stepping is likely a spinal automatism generated within the spinal locomotion center and regulated by both ascending and descending brainstem tracts. Clinicians and family members of neurologically devastated patients should be aware that this and other movements can occur during the late stages of central herniation preceding and following brain death.

Aged↗

PubMed1994

Patent foramen ovale and brain infarct. Echocardiographic predictors, recurrence, and prevention.

BACKGROUND AND PURPOSE: Paradoxical embolism through a patent foramen ovale is a recognized cause of stroke, but clinical predictors, recurrence rate, and prevention of brain infarcts in patients with patent foramen ovale have not been determined. We reviewed transesophageal echocardiographic records to ascertain echocardiographic predictors and optimal prophylaxis for patent foramen ovale-related infarcts. METHODS: A patent foramen ovale was identified in 74 patients during 615 transesophageal echocardiograms by color Doppler or saline contrast during a 60-month period. On the basis of final clinical situation, the patients were divided into the following groups: group 1, infarct with patent foramen ovale a likely cause (n = 16); group 2, infarct with patent foramen ovale an unlikely cause (n = 23); and group 3, no infarct (n = 35). Transesophageal echocardiograms were reviewed to assess patent foramen ovale characteristics and associated cardio-embolic sources without knowledge of clinical details or group assignment. Follow-up after a patent foramen ovale-related infarct was obtained by telephone or written correspondence in 15 of 16 group 1 patients. RESULTS: Atrial septal aneurysms were more common in group 1 (38%) compared with group 2 (10%) and group 3 (8%) (P = .02). Contrast right-to-left shunting occurred in 88% of group 1 (P = .06) and 86% of group 2 (P = .07) compared with 60% of group 3. Prevention of recurrence in subjects with presumed patent foramen ovale-related brain infarcts varied. Aspirin was usually chosen after initial brain ischemia. Warfarin and patent foramen ovale closure were usually reserved for subjects with symptoms of brain ischemia while taking aspirin or those who required warfarin or cardiac surgery for other indications. No recurrent infarcts occurred in 15 patients during a mean follow-up period of 28 months. CONCLUSIONS: Atrial septal aneurysm and right-to-left shunt may be predictive of a patent foramen ovale that predisposes a patient to stroke. Aspirin may provide sufficient infarct prophylaxis after initial ischemia. Warfarin and surgical correction should likely be reserved for those in whom aspirin is not effective or those who require warfarin or cardiac surgery for other reasons until prospective studies are available.

Adult↗

PubMed1993

Asymmetry of forearm rolling as a sign of unilateral cerebral dysfunction.

We compared the reliability of asymmetry of forearm rolling (rotation of one forearm around the other in front of the torso) as a sign of unilateral cerebral dysfunction with that of other standard clinical tests. We studied 62 patients with radiologically confirmed unilateral cerebral lesions and 20 control subjects with normal imaging. Asymmetric forearm rolling was the most sensitive indicator of unilateral hemispheric disease (85%). This simple test is a useful addition to the neurologic examination.

Adult↗

PubMed1993

Loss of ipsidirectional quick phases of torsional nystagmus with a unilateral midbrain lesion.

We report a patient with a long-standing, unilateral lesion of the midbrain who showed ipsidirectional loss of torsional quick phases, impairment of all vertical eye movements and normal horizontal eye movements. The findings are consistent with recent reports of the effects of experimental lesions, in monkeys, of the rostral interstitial nucleus of the medial longitudinal fasciculus and the interstitial nucleus of Cajal.

Aged↗

PubMed1992

Comparison of predictable smooth ocular and combined eye-head tracking behaviour in patients with lesions affecting the brainstem and cerebellum.

We compared the ability of eight normal subjects and 15 patients with brainstem or cerebellar disease to follow a moving visual stimulus smoothly with either the eyes alone or with combined eye-head tracking. The visual stimulus was either a laser spot (horizontal and vertical planes) or a large rotating disc (torsional plane), which moved at one sinusoidal frequency for each subject. The visually enhanced vestibulo-ocular reflex (VOR) was also measured in each plane. In the horizontal and vertical planes, we found that if tracking gain (gaze velocity/target velocity) for smooth pursuit was close to 1, the gain of combined eye-hand tracking was similar. If the tracking gain during smooth pursuit was less than about 0.7, combined eye-head tracking was usually superior. Most patients, irrespective of diagnosis, showed combined eye-head tracking that was superior to smooth pursuit; only two patients showed the converse. In the torsional plane, in which optokinetic responses were weak, combined eye-head tracking was much superior, and this was the case in both subjects and patients. We found that a linear model, in which an internal ocular tracking signal cancelled the VOR, could account for our findings in most normal subjects in the horizontal and vertical planes, but not in the torsional plane. The model failed to account for tracking behaviour in most patients in any plane, and suggested that the brain may use additional mechanisms to reduce the internal gain of the VOR during combined eye-head tracking. Our results confirm that certain patients who show impairment of smooth-pursuit eye movements preserve their ability to smoothly track a moving target with combined eye-head tracking.

Adult↗

PubMed1992

Datura delirium.

Poisoning with tropine alkaloids from cultivated plants and pharmaceuticals is an uncommon cause of delirium and coma. We report a patient with a toxic delirium following ingestion of the tropine alkaloid-containing root of Datura innoxia. Thin-layer chromatography and gas chromatography/mass spectrometry confirmed the presence of atropine and scopolamine in samples of the ingested root. Routine clinical toxin screens may not include an assay for tropine alkaloids. A specific tropine alkaloid assay may provide supporting evidence. The clinical, electroencephalographic, and therapeutic aspects of anticholinergic poisoning are discussed.

Aged↗