Biomedical subjects

N Arriada

Publications and source records attributed to N Arriada.

3 recordsLinked to original sources

PubMed2001

Treatment of hydrocephalus in adults by placement of an open ventricular shunt.

OBJECT: Ventricular shunt placement is the neurosurgical procedure most frequently associated with complications. Over the years, it has been a growing concern that the performance of most shunting devices does not conform to physiological parameters. An open ventriculoperitoneal (VP) bypass with a peritoneal catheter for which the cross-sectional internal diameter was 0.51 mm as a distinctive element for flow resistance was evaluated for use in the treatment of adult patients with hydrocephalus. METHODS: During a 2-year period, open shunts were surgically implanted in 54 adults with hydrocephalus; conventional shunts were implanted in 80 matched controls. Periodic evaluations were performed using neuroimaging studies and measures of clinical status. All patients were followed from 12 to 36 months. 18.5 +/- 4 months for patients with the open shunt and 19.1 +/- 8.1 months for controls (mean +/- standard deviation). The device continued to function in 50 patients with the open shunt (93%) and in 49 controls (61%: p < 0.001). The Evans index in patients with the open shunt was 0.33 +/- 0.09 throughout the follow up. No cases of infection, overdrainage, or slit ventricles were observed: the index in controls was 0.28 +/- 0.08; 60% of them developed slit ventricles. During the follow-up period occlusion occurred in four patients with the open shunt (7%) and in 31 controls (39%: p < 0.001). CONCLUSIONS: The daily cerebrospinal fluid (CSF) drainage through the open VP shunt is close to 500 ml of uninterrupted flow propelled by the hydrokinetic force generated by the combination of ventricular pressure and siphoning effect. It complies with hydrokinetic parameters imposed by a bypass connection between the ventricular and peritoneal cavities as well as with the physiological archetype of continuous flow and drainage according to CSF production. The open shunt is simple, inexpensive, and an effective treatment for hydrocephalus in adults.

Adolescent↗

PubMed2000

Cardiovascular dysfunction in multiple sclerosis.

Cardiovascular dysfunction (CD) in multiple sclerosis (MS) is related to involvement of reflex pathways in the brainstem. The battery of CD tests was applied to a group of 40 healthy subjects and 40 patients with MS, divided in 2 subgroups according to the expanded disability status scale (EDSS). The tests included: 1) postural blood pressure changes, 2) postural heart rate changes, 3) heart rate changes on inspiration/forced expiration and 4) ECG R-R interval measurement on the Valsalva maneuver. Both groups were subjected to the functional independence scale (FIM). Imaging studies were reviewed and autonomic dysfunction at other levels was explored. The results showed a statistically significant difference (P < 0.05) in all tests when comparing patients to controls. Tests 1 and 4 had the highest significance, with findings of more severe involvement in patients with a higher EDSS and lower FIM. A correlation was also found between CD and brainstem lesions on MRI (P < 0.01). A significant number of MS patients had evidence of CD. Test 1 may be considered a simple marker, in daily clinical practice, to detect subclinical CD. Subclinical CD is a cause of disability in this group of patients.

Adolescent↗

PubMedDate not supplied

[Interferon-beta 1a in relapsing-remitting multiple sclerosis. First report of a Mexican population].

OBJECTIVE: We present the results of a prospective and a longitudinal study of IFN-beta 1a (Rebif) in the treatment of Mexican patients with relapsing-remittin multiple sclerosis (MS). PATIENTS AND METHODS: Twenty five patients were included, all of them fulfilled the diagnostic criteria proposed by Poser, had a clinical evolution of at least 2 years, had 2 to 3 acute attacks of MS in the 12 months preceding study entry and an EDSS < 5.5. Six patients were excluded from the trial, one because of anaphylactic shock, 2 progressed to the chronic form and 3 decided not to continue in the study. These patients were considered as treatment failures and represented 24% of the participants entering the trial. The remaining 19 patients (mean age 29.8, 74% females) completed 2-year follow-up. The mean time of disease duration was 48.8 months. Six million units of IFN-beta 1a were applied thrice weekly, in 8 patients (42%) dosage reduction to 6 millions units twice a week was necessary because of leukopenia or elevation in liver enzymes. RESULTS: In the year before treatment with IFN-beta 1a patients had 2.7 +/- 0.93 acute attacks, after treatment the mean number of acute attacks per year was reduced to 1.94 +/- 2.39 (28.9% reduction). When analyzed by gender there was a 62.9% reduction in acute episodes per year in women and a 27.7% reduction in men (p < 0.05). The most frequent side effects were fatigue, headache, local skin reactions, depressed mood, myalgia, weight variations and somnolence. A few patients developed leukopenia, anemia or elevated liver enzymes. In 31.25% of the patients there was an increase in the number of lesions on MRI, in 31.25% there was a reduction in the number of lesions and in 37.5% no change was noted. CONCLUSION: The best-tolerated dose of IFN-beta 1a was 12 million units/week in women and 18 million units/week in men.

Adjuvants, Immunologic↗