Whole bowel irrigation as a decontamination procedure after acute drug overdose.

Whole bowel irrigation, routinely used before colonoscopy, is evaluated as a potential gastrointestinal decontamination procedure for acute drug overdose. Nine adult volunteers, who served as their own controls, each ingested 5.0 g of ampicillin trihydrate on two occasions, one week apart. Whole bowel irrigation with polyethylene glycol electrolyte lavage solution was performed one hour after one ingestion. Serial serum ampicillin levels, electrolytes, osmolalities, body weights, and hematocrits were obtained. The areas under the concentration vs time curves for ampicillin were computed for both groups, and their means were compared. Mean duration of the procedure was 234 minutes and mean volume of infused polyethylene glycol electrolyte lavage solution was 7.7 L. Whole bowel irrigation produced a 67% decrease in ampicillin absorption and there were no significant changes in body weight, hematocrit, serum electrolytes, or osmolality. We conclude that whole bowel irrigation is an effective and safe gastrointestinal decontamination procedure for acute drug ingestion.

Clinical spectrum of sulfonylurea overdose and experience with diazoxide therapy.

We retrospectively reviewed our 10-year experience with the management of sulfonylurea overdose. There were 40 overdoses in 37 patients aged 1 to 78 years, with two deaths and one patient being left in a chronic vegetative state. Blood sugar levels ranged from normal to severe recalcitrant hypoglycemia. Maximal duration of recurrent hypoglycemia was 82 hours. In 21 of 31 patients with hypoglycemia, response to hypertonic glucose therapy was poor, resulting in recurrent hypoglycemia. Six of these patients were treated with intravenous diazoxide and had prompt correction. Overdose of sulfonylurea drugs may produce severe, protracted hypoglycemia poorly responsive to hypertonic glucose therapy. Treatment with diazoxide is rational and effective and may be lifesaving.

Multiple-dose charcoal and whole-bowel irrigation do not increase clearance of absorbed salicylate.

BACKGROUND: This study assesses whether oral multiple-dose charcoal therapy (MDC) or whole-bowel irrigation (WBI) enhances the excretion of previously absorbed salicylate. METHODS: A controlled, randomized, three-limbed crossover protocol was used in nine humans who ingested aspirin. Salicylate levels were measured in serial serum specimens and 32-hour urine collections and kinetic parameters were calculated. RESULTS: There were no differences among the control (CTL), MDC, or WBI groups for area under the serum concentration vs time curve (CTL, 2320 +/- 501 mg/L.h MDC, 2040 +/- 454 mg/L.h; WBI, 2093 +/- 418 mg/L.h) or for urinary salicylates (CTL, 54.9% +/- 9.4%; MDC, 50.9% +/- 8.0%, WBI, 52.4% +/- 13.7% of ingested dose). CONCLUSIONS: Our data do not support the use of either MDC or WBI to enhance the excretion of previously absorbed salicylate in poisoned patients. In patients with drug overdoses, a clear rectal effluent remains as the endpoint for WBI.

Does multiple-dose charcoal therapy enhance salicylate excretion?

Multiple-dose charcoal therapy has been shown to increase the excretion of some drugs. This study assesses the effects of this intervention on salicylate excretion in the postabsorptive phase. Ten human volunteers participated in this randomized, controlled, crossover, two-limbed protocol. On two occasions each volunteer ingested 2880 mg of aspirin. During the experimental limb, 25 g of activated charcoal was ingested at 4, 6, 8, and 10 hours after drug ingestion. Pharmacokinetic data were derived from serial serum salicylate concentrations, and urinary salicylate excretion was quantified. Treatment effects were 9% and 18%, respectively. Although both are significant, they are clinically modest, making multiple-dose charcoal therapy of questionable value for acute salicylate poisoning. Controlled data demonstrating the clinical efficacy of this therapy are required to validate it as an intervention for this condition.

Hepatotoxicity in acute iron poisoning.

Although liver injury is a recognized consequence of acute iron poisoning, its description is limited to several case reports. It appears to be dose-related, however, there are published reports of severe iron poisoning without liver injury. The purpose of this study is to examine the hypothesis that this is a dose-related phenomenon and to identify the serum iron concentration of risk for this outcome. The design of this study is a retrospective review of our hospital's experience over 20 years. Extracted data included demographics, time of ingestion, highest serum iron concentration and highest hepatic transaminase activity. Iron poisoning was defined as a serum iron concentration >300 microg/dL (55 micromol/L) within 12 hours of ingestion. Hepatotoxicity was defined as a serum transaminase (either ALT or AST) >150 U/L. Severe hepatotoxicity was defined >1000U/L. Seventy-three patients (1-48 years old) participated in the study and of these patients 60 (47 female) did not have hepatotoxicity. Their serum iron concentrations were 300-704 microg/dL (55-128 micromol/L). Thirteen patients had hepatotoxicity and of these patients, nine had severe liver injury. Severe injury was associated with serum iron concentrations well in excess of 1000 microg/dL (182 micromol/L). Our data support hepatotoxicity due to iron poisoning as a dose-related phenomenon with clinically important cases unlikely with a serum iron concentration of < 700 microg/dL (128 micromol/L) within the first 12 hours. Clinically important hepatotoxicity occurs with values in excess of 1000 microg/dL (182 micromol/L).

Whole-bowel irrigation versus activated charcoal in sorbitol for the ingestion of modified-release pharmaceuticals.

Overdose with modified-release pharmaceuticals is an increasing phenomenon. This study examines whole-bowel irrigation as a potential decontamination strategy after overdose with enteric-coated acetylsalicylic acid and compares it with administration of activated charcoal in sorbitol, which is currently the recommended intervention. A three-phase randomized crossover protocol was used in 10 adult volunteers. Each volunteer ingested nine 325 mg doses of enteric-coated acetylsalicylic acid on three occasions, with at least 1 week between each administration period. Serum samples were analyzed for salicylic acid concentration by HPLC. Both interventions decreased peak salicylic acid concentration, time-to-zero salicylic acid concentration, and AUC when compared with control (p less than 0.01). Whole-bowel irrigation was superior to activated charcoal in sorbitol by all three criteria (p less than 0.05). Adverse effects were qualitatively and quantitatively greater during activated charcoal in sorbitol, and the volunteers preferred whole-bowel irrigation over charcoal in sorbitol. Our data suggest that whole-bowel irrigation should be considered for overdose of other modified-release pharmaceuticals.

American Academy of Pediatrics. Committee on Injury and Poison Prevention. Safe transportation of newborns at hospital discharge.

All hospitals should set policies that require the discharge of every newborn in a car safety seat that is appropriate for the infant's maturity and medical condition. Discharge policies for newborns should include a parent education component, regular review of educational materials, and periodic in-service education for responsible staff. Appropriate child restraint systems should become a benefit of coverage by Medicaid, managed care organizations, and other third-party insurers.

American Academy of Pediatrics. Committee on Injury and Poison Prevention. Transporting children with special health care needs.

Children with special health care needs should have access to proper resources for safe transportation. This statement reviews important considerations for transporting children with special health care needs and provides current guidelines for the protection of children with specific health care needs, including those with a tracheostomy, a spica cast, challenging behaviors, or muscle tone abnormalities as well as those transported in wheelchairs.

Childhood diethylene glycol poisoning treated with alcohol dehydrogenase inhibitor fomepizole and hemodialysis.

Diethylene glycol (DEG), a commonly used solvent, has been implicated in multiple poisoning deaths, the most recent being the Haitian acetaminophen tragedy. Unlike the more commonly seen ethylene glycol ingestion, little is understood of DEG metabolism or kinetics in humans. This has made the clinical presentation, biochemical correlates, and treatment options unclear. Patients presenting less than 12 hours after DEG ingestion may not show metabolic acidosis, whereas those presenting later may show florid metabolic acidosis. Kinetic data lend support to these observations. We report a case of DEG ingestion in a 17-month-old girl who was managed with activated charcoal, fomepizole (a recently available alcohol dehydrogenase inhibitor), and hemodialysis (HD). Pre-HD and post-HD DEG levels support clearance of DEG with HD.

Interaction between N-acetylcysteine and activated charcoal: implications for the treatment of acetaminophen poisoning.

STUDY OBJECTIVE: To determine if the presence of N-acetylcysteine reduces the ability of activated charcoal to adsorb acetaminophen both in the absence and presence of a coingestant. DESIGN: In vitro laboratory study. SETTING: University hospital research laboratory. MEASUREMENTS AND MAIN RESULTS: The adsorption of acetaminophen and salicylic acid by activated charcoal in the presence and absence of N-acetylcysteine was measured in vitro. Acetaminophen and salicylic acid analyses were conducted with high-performance liquid chromatography. Adsorption data were compared using the appropriate parametric statistical test. The addition of N-acetylcysteine significantly decreased the binding of acetaminophen by activated charcoal (p<0.005). When salicylic acid was added to simulate a coingestant, N-acetylcysteine significantly decreased salicylate adsorption by charcoal (p<0.001). CONCLUSIONS: The presence of N-acetylcysteine reduces the ability of activated charcoal to adsorb acetaminophen and coingestants. In vivo data will be required to determine the clinical relevance of these interactions.

Toxicokinetics and toxicodynamics of iron poisoning.

Iron is a unique poison because it is not a xenobiotic. It is an essential element and highly reactive. Because of the critical dependence upon iron and its potential to damage tissues, elaborate mechanisms have evolved for its efficient absorption, transport, cellular uptake, storage and conservation. These are incompletely understood with even less being known after the ingestion of an overdose. Thus little is known of iron's toxicokinetics. Less is known regarding its absorption. A saturable active receptor mediated mechanism has been described, however, a passive mechanism is speculated to exist. After overdose, the amount absorbed is unknown but is likely in the order of 10%. Transferrin capacity is saturated after the absorption of a toxic dose resulting in much of the circulating iron being hydrated ferric ion. The liver clears most of the circulating iron and the plasma half-life after overdose is similar to the 4-6 h observed after therapeutic dosing. There is no mechanism for iron excretion. The toxicodynamics are a consequence of the chief mechanism for iron-induced tissue damage, free radical production with resultant lipid peroxidation. Therefore target organs and tissues are those exposed to high concentrations of iron and have a high metabolic activity. These are the gastrointestinal epithelium, cardiovascular system and the liver. Five distinct clinical phases are recognized: Gastrointestinal Toxicity, Relative Stability, Circulatory Shock and Acidosis, Hepatotoxicity and Gastrointestinal Scarring. Rational treatment of iron poisoning requires a thorough understanding of its toxicokinetics and toxicodynamics.

Neonatal withdrawal from maternal volatile substance abuse.

AIM: To determine whether neonates born to mothers who are volatile substance abusers are at risk for an abstinence syndrome. METHODS: A consecutive sample of infants born to volatile substance abusing mothers was studied over four years, in a university affiliated medical centre with a variable mix of primary, secondary, and tertiary care patients. Infants were clinically scored with the Finnegan Neonatal Abstinence Scoring System. Those who fulfilled a priori scoring criteria were treated with phenobarbital and scoring was continued. RESULTS: There were 48 babies of whom 32 fulfilled the criteria for pharmacotherapy. All eight babies with the characteristic odour, and 15 of the 21 born to mothers with that odour, fulfilled these criteria. The typical symptoms were excessive and high pitched cry, sleeplessness, hyperactive Moro reflex, tremor, hypotonia, and poor feeding. Mean age of onset of treatment was 27.1 hours and mean duration was 5.8 days. Treatment was judged effective in 17 of 27, while benefit was borderline in three and absent in seven. CONCLUSIONS: It is suggested that there is an identifiable neonatal volatile substance abuse abstinence syndrome. The characteristic chemical odour in the neonate or mother is a marker for its occurrence, and phenobarbital treatment seems to be effective. The Finnegan Scoring System seems to be useful for grading its severity.

Vaccination of emergency department patients at high risk for influenza.

OBJECTIVE: To determine the proportion of Canadian emergency department (ED) patients who are at risk for increased morbidity from influenza but were not vaccinated and to determine emergency physicians' (EPs') willingness to screen for and prescribe influenza vaccination. METHODS: The authors surveyed a convenience sample of patients presenting during a one-week period at each of four EDs in Winnipeg, Manitoba, Canada, after the end of the seasonal period for vaccination. They also surveyed all full-time EPs in Winnipeg. RESULTS: Fifty-three percent of emergency patients at risk for increased morbidity from influenza had not been vaccinated and 59.3% of them were willing to be vaccinated during an emergency visit. This represents 31.6% (+/-3.1%) of all high-risk patients and 15% of all emergency patients. High-risk patients who did not have a regular physician were less likely to have been vaccinated (OR 0.165, p = 0.018). Most EPs rarely or never offer influenza vaccination (30% and 57%, respectively). Seventy-six percent of them were willing to prescribe vaccination. CONCLUSION: Many ED patients are at risk for increased morbidity from influenza and have not been vaccinated. The majority of them are willing to be vaccinated during an emergency visit and the majority of EPs are willing to prescribe vaccination. Emergency department vaccination for influenza should be considered as a strategy to increase vaccination among high-risk groups.

Validation of the Ottawa Ankle Rules in children with ankle injuries.

OBJECTIVES: The Ottawa Ankle Rules (OAR) have been found to be 100% sensitive in adult patients with ankle injuries, and application of the OAR has resulted in a 28% reduction in the number of x-rays ordered. The objectives of this study were to determine the sensitivity and specificity of the OAR in children and to determine the potential change in x-ray utilization. METHODS: Children, aged 2-16 years, presenting to the EDs of two children's hospitals, with an ankle injury in the previous 48 hours, were enrolled. All patients were assessed by either staff physicians or fellows. X-rays were ordered according to standard clinical practice. Prior to reviewing x-rays, the physical examination was recorded on a standardized form. Positive outcomes (clinically significant) were defined as fractures with fragments > or =3 mm. Patients not x-rayed and asymptomatic at five to seven days postinjury were considered to have no significant fracture. RESULTS: Six hundred seventy patients were enrolled. The OAR were 100% sensitive (95% CI = 95% to 100%) for significant ankle fractures, with a specificity of 24% (95% CI = 20% to 28%). The OAR were 100% sensitive (95% CI = 82% to 100%) for the midfoot, with a specificity of 36% (95% CI = 29% to 43%). If the OAR had been followed, there would have been a reduction of ankle x-rays by 16% and foot x-rays by 29% without missing any clinically significant fracture. However, analysis of the two hospitals showed that if the rules had been applied, one would have a reduction in x-rays, while the other center would have an increase. CONCLUSIONS: This study demonstrates the OAR to be sensitive for detecting clinically significant (> or =3 mm) ankle and midfoot fractures in children. The application of these rules may reduce the number of x-rays ordered. A further study is required to determine the effect of using the OAR in clinical practice.

Variation in utilization of computed tomography scanning for the investigation of minor head trauma in children: a Canadian experience.

OBJECTIVES: To compare the utilization rates of CT scans in investigating minor head trauma in children in Canada, to identify the injuries determined by these scans, and to identify clinical findings that are highly associated with its diagnosis and the injury itself. METHODS: A retrospective cohort study involving nine pediatric hospitals in Canada was conducted. A structured data collection method was used. Inclusion criteria included age 16 years or less, history of blunt head trauma, and a Glasgow Coma Scale score (GCS) greater than or equal to 13. Data collected included demographic information, type of injury, relevant clinical information, computed tomography (CT) scan data, and clinical outcome. Clinical findings associated with CT scan and positive CT scan were identified using logistic regression. RESULTS: One thousand one hundred sixty-four children were included in the study. One hundred seventy-one (15%) had a CT scan, of which 60 (35%) were abnormal. There was a significant difference in the rate of ordering of CT scans among the participating hospitals, but no significant difference in the rate of abnormal CT scans. Mechanism of injury, GCS, and loss of consciousness were significantly related to the presence of an abnormal CT scan. CONCLUSIONS: Although there is a significant difference in the utilization of CT scans to investigate minor head trauma in children across Canada, there is no significant difference in the frequency of head injuries in these patients. This suggests that it may be possible to determine clinical criteria that are predictive of a head injury in these patients.

Does iron deficiency raise the seizure threshold?

To determine the effect of iron status on the seizure threshold, measures of iron sufficiency were prospectively evaluated in 51 children presenting to a pediatric emergency department with a febrile illness with (26) or without (25) an associated febrile seizure. A higher proportion of children from the febrile seizure group had a family history of mental retardation (5/26 versus 0/25, P = .02) or of previous febrile seizures (10/26 versus 2/23, P = .01). The two groups were otherwise comparable for age, sex, race, family history of afebrile seizures, temperature at presentation, white blood cell count, differential, and vitamin and antibiotic use. Patients with febrile seizures were less frequently iron deficient as defined by a free erythrocyte protoporphyrin level above 0.80 ng/L (2/23 versus 10/25, P < .01), hemoglobin concentration less than 110 g/L (1/26 versus 6/25, P < .03), hematocrit less than 0.30 L/L (0/22 versus 4/25, P < .02), mean corpuscular hemoglobin less than 20 pg (0/25 versus 3/24, P < .04), mean corpuscular volume less than 65 fL (0/26 versus 4/24, P < .02), and platelet count higher than 550 x 10(9)/L (0/26 versus 3/25, P < .04). This association was even stronger when adjusted for differences in family history. None of the patients in the febrile seizure group was being treated for iron deficiency at presentation, whereas three of 25 controls used an iron supplement (P < .04). Iron deficiency may protect against the development of febrile seizures.

Recent advancements in pediatric toxicology.

Ingestion of potentially poisonous agents is a common reason for children to present to an emergency department. The clinician must decide whether gastrointestinal decontamination is indicated for these patients. The controversy over the type of gastrointestinal decontamination is resolving and recent recommendations are reviewed. Also two new antidotes, fomepizole for toxic alcohols and octreotide for sulfonylureas, are reviewed.

Pediatric trauma registries: the foundation of quality care.

BACKGROUND/PURPOSE: Traumatic injuries cause substantial morbidity and mortality in children. Trauma registries are essential to assess and improve standards of trauma care. An interprovincial study of pediatric trauma between 6 centers across Canada who use identical software components was completed. METHODS: Data were collected from April 1, 1995 to December 31, 1998 for children aged 1 day to 17 years with an injury severity score of > or = 12. Cause of injury, injury time and day, gender, age, injury scores, length of hospital stay, and outcomes were compared. RESULTS: A total of 1,276 patients were included. Mean age was 10.3 +/- 5.6 years. Motor vehicle collisions were the most common mechanism of injury (56%). Boys were more often injured (66%; P < .05). Injuries occurred mainly between 1600 and 2400 hours (P < .0001). Mean hospital stay was 11.5 +/- 16.6 days. The longest stays in the hospital were among those who had an abdominal abbreviated injury score (AIS) of 1 (P < or = .03). Patients with similar injury severities remained twice as long in Winnipeg Children's Hospital (hospital 5), hospital 2, and hospital 6 as compared with patients in hospital 3 (P < .05). Differences existed in discharge placement between hospitals (P < .0001). CONCLUSIONS: This study was the first to compare pediatric patients in multiple Canadian centers using identical trauma registries. Variations in length of stay and discharge placements between hospitals were identified. Further analysis of data in the registries may clarify these differences and serve as a foundation for hospitals to improve the quality of patient care.

Leaded gasoline abuse: the role of tetraethyl lead.

Volatile substance abuse is practised worldwide however reports of the abuse of leaded gasoline have been limited to northern Canada, southwestern USA and the Australian Outback. Chronic, heavy abuse of leaded gasoline results in an encephalopathy, cerebellar and corticospinal symptoms and signs, dementia, mental status alterations, and persistent organic psychosis. Much of this is due to the hydrocarbons of gasoline while the tetraethyl lead contributes to the altered mental status and is responsible for the persistent psychosis. Lead chelation therapy is not rational and has not been shown to benefit these patients.

Inefficacy of gastric emptying procedures.

Gastric lavage or ipecac-induced emesis are routinely recommended in the management of the acutely poisoned patient. Efficacy of either procedure has not been shown. Three cases are described clearly demonstrating inefficacy of emesis and wide bore orogastric lavage. The role of these procedures requires careful controlled evaluation. Until the publication of supportive data, their efficacy is unproven.