Biomedical subjects

M W Shannon

Publications and source records attributed to M W Shannon.

3 recordsLinked to original sources

PubMed1992

Duration of QRS disturbances after severe tricyclic antidepressant intoxication.

While the clinical toxicity of tricyclic antidepressants, particularly the development of seizures and arrhythmias, has been strongly correlated with a QRS interval of greater than or equal to 100 msec on electrocardiography, the resolution pattern of QRS abnormalities remains poorly defined. We prospectively monitored 22 consecutive patients who were referred to a regional poison center after a tricyclic antidepressant ingestion associated with a QRS interval of greater than 100 msec. An ECG was obtained every 6-8 h in all patients until the QRS interval was less than 100 msec. Among enrolled patients the mean maximal QRS interval was 145 msec. Ten patients (45.5%) developed seizures while 6 (27%) developed cardiac arrhythmias. The time from ingestion to the last ECG demonstrating a widened QRS interval was a median 12.3 h (range 1-70 h); the time from ingestion to the first ECG with a QRS less than 100 msec was a median 19.3 h (range 3-78 h). No patients developed seizures or life-threatening cardiac arrhythmias after the QRS interval was less than 100 msec. Ten patients received sodium bicarbonate while 12 did not. There were no significant differences in the duration of QRS widening between the two groups. These data suggest that the typical period of QRS prolongation after severe tricyclic antidepressant ingestion is 12-18 h but may be as long 3 d. The factors which determine the duration of QRS widening are unclear. Sodium bicarbonate may not reduce the total duration of QRS disturbances.

Adolescent↗

PubMed1992

Lead intoxication in infancy.

Four years of experience in the evaluation and management of lead intoxication in the first year of life were reviewed. This study was conducted in a lead referral program within the state of Massachusetts, whose comprehensive lead laws include extensive (and now mandatory) lead screening of all children. Over the period of study, 50 (14%) of 370 new patients enrolled in the program were infants aged 12 months or younger. Median age of these infants was 11 months (range 1 through 12 months). Mean peak lead level was 39.0 micrograms/dL while the mean peak erythrocyte protoporphyrin concentration was 111.9 micrograms/dL of whole blood. Thirty-two percent of infants were ambulatory at the time lead intoxication was diagnosed; only 24% had a history of pica. Twenty-six percent of parents were welfare dependent. Apparent sources of plumbism included house-hold renovation (n = 20), direct ingestion of paint chips (n = 10), formula preparation with lead-contaminated water (n = 9), lead dust importation (n = 1), and congenital exposure to elevated maternal lead level (n = 1). In 9 cases the source was not found. When this profile was compared with that of a randomly selected group of 47 children aged 18 through 30 months, who were seen in the lead program during the same interval, apparent sources of intoxication in the older group were paint chip ingestion (n = 41), household renovation (n = 2), and unknown (n = 4) (P less than .0001). On the basis of these data, it is concluded that lead intoxication in infants is common and has significantly different origins from that in toddlers.(ABSTRACT TRUNCATED AT 250 WORDS)

Cooking and Eating Utensils↗

PubMed1991

The adsorption of salicylates by a milk chocolate-charcoal mixture.

STUDY OBJECTIVE: To evaluate the adsorptive capacity of a milk chocolate-charcoal mixture to aspirin, compared with superactivated charcoal and conventional activated charcoal. DESIGN: A prospective, randomized, crossover study. SETTING: The Massachusetts Poison Control Center office in The Children's Hospital, Boston. TYPE OF PARTICIPANTS: Six healthy adult volunteers with no known allergies to aspirin or chocolate, bleeding disorders, or peptic ulcer disease. INTERVENTIONS: Each participant ingested 975 mg of crushed aspirin on separate days, followed by either water; 10 g milk chocolate-charcoal mixture; 10 g SuperChar Liquid; or 10 g Actidose Aqua activated charcoal. Total serum salicylate concentrations were determined by high-performance liquid chromatography at zero, one, two, four, eight, and 24 hours after ingestion. MEASUREMENTS AND MAIN RESULTS: Neuman-Keuls analysis was used to measure time-to-peak concentration, which was reduced by SuperChar Liquid, 67%; milk chocolate-charcoal mixture, 106%; and activated charcoal, 56%. Aspirin absorption was calculated using Neuman-Keuls analysis to measure area under the concentration-time curve. Total aspirin absorption was reduced by SuperChar, 67%; milk chocolate-charcoal mixture, 50%; and activated charcoal, 2%. There was no difference in serum salicylate concentrations between SuperChar and milk chocolate-charcoal mixture at all time intervals. Also, all serum salicylate concentrations with milk chocolate-charcoal mixture were consistently lower than with activated charcoal. CONCLUSION: Although the formulation of milk chocolate with activated charcoal reduces its adsorptive capacity compared with superactivated charcoal, it is still able to bind aspirin effectively and is superior to conventional activated charcoal. Further research may improve the binding and palatability of milk chocolate-charcoal mixture, especially for home use.

Adsorption↗