Comprehensive Guidelines for Managing Poisoning in Adults

Introduction

Overview of Poisonings and Drug Overdoses

A systematic review documented the global epidemiological profile of unintentional drug overdoses, revealing a wide variability in prevalence and mortality rates across different regions and periods. The review emphasized a significant increase in drug overdose-related deaths and hospitalizations, primarily driven by the misuse of prescription opioids, cocaine, and heroin. This trend underscores the evolving nature of the overdose crisis, which has increasingly affected both urban and rural areas (Martins et al., 2015).

In 2023, over 2 million suspected human toxic exposures were managed by poison control centers in the United States, reflecting the extensive burden on healthcare systems. These exposures result in direct medical and significant societal costs, including productivity losses and long-term health consequences. The management and prevention of poisonings and drug overdoses require coordinated efforts from healthcare providers, public health agencies, and policymakers to address the underlying causes and reduce the associated morbidity and mortality (Gummin et al., 2023).

Importance of Poison Control Centers

In 2023, over 2 million suspected human toxic exposures were managed by poison control centers in the United States (Gummin et al.). Poison control centers play a crucial role in public health by providing immediate, expert guidance in toxic exposure cases, reducing the burden on emergency healthcare services, and improving patient outcomes. These centers offer vital services such as real-time consultation, education, and data collection, essential for immediate patient care and long-term public health strategies.

Poison control centers help prevent unnecessary emergency department visits, which can be costly and resource-intensive. For example, a study found that after discontinuing poison control services in Louisiana, there was a significant increase in self-referrals to healthcare facilities, leading to higher costs and resource utilization (King & Palmisano, 1991). Another study demonstrated that using poison control centers can save substantial costs by managing cases at home and avoiding unnecessary hospital admissions (Zaloshnja et al., 2006).

Furthermore, poison control centers contribute to public health by participating in toxico-surveillance and environmental health monitoring. They collect and analyze data on poisoning cases, which helps identify emerging hazards and guide public health interventions. This data is also crucial for regulatory actions, product safety evaluations, and public education campaigns (Laborde, 2004).

Scope of the Guide

This guide reviews the general approach and initial management of adult patients with suspected or confirmed poisoning. Specific management of common drug overdoses is discussed in separate reviews, including critically ill adults and children with unknown overdoses.

Epidemiology

Poisoning represents a significant public health issue, affecting individuals across all age groups and socio-economic backgrounds. In 2022, 2,064,875 reported human exposure to toxic substances in the United States (Gummin et al.). This data underscores the extensive reach of toxic exposures and their impact on public health systems.

The data collected by America's Poison Centers (APC) is robust, incorporating reports from all 55 poison centers across the United States. These centers upload case data in near real-time, providing a comprehensive surveillance system that captures the incidence and characteristics of toxic exposures. This extensive dataset allows for detailed analysis and identification of poisoning trends, facilitating targeted public health interventions and resource allocation (Gummin et al., 2023).

Age and Gender Distribution

Poisonings occur in all age groups but are most prevalent in children under five years and adults aged 20-40 years. Gender distribution varies with age; pediatric cases are slightly more common in boys, whereas adult cases are more common in women, particularly in self-poisoning incidents.

Detailed Findings:

1.     Pediatric Poisonings:

o   Children under five years are at a high risk for accidental poisoning. A study found that the most common agents of acute poisoning in this age group were household products and medications (Lee et al., 2019).

o   Boys are more frequently affected than girls in younger age groups. However, this trend reverses in adolescents, where intentional poisonings become more common and are more frequently observed in females (Beauchamp et al., 2020).

2.     Adult Poisonings:

o   Among adults, females are more commonly involved in self-poisoning cases, particularly with pharmaceuticals such as analgesics and antidepressants. Studies have shown that women are more likely to use medications for intentional overdoses (McGlone & Teece, 2013).

o   In contrast, men are more likely to experience poisoning from substances such as alcohol and industrial chemicals. Males also have a higher incidence of fatal outcomes in poisoning cases (Rogers & Heard, 2007).

3.     Elderly Poisonings:

o   Older adults are also significantly affected by poisonings, often due to polypharmacy and medication errors. Female older adults are more frequently involved in poisonings related to adverse drug reactions, while males are more often affected by alcohol-related toxicity (Beauchamp et al., 2018).

4.     Global Trends:

o   International studies reveal similar patterns, with a higher prevalence of poisoning in children and young adults. For instance, in Southern India, a significant number of poisoning cases among males were due to organophosphates, whereas females frequently used pharmaceuticals (Kanchan & Menezes, 2008).

o   In Palestine, males were more commonly involved in unintentional poisonings, while intentional poisonings were more frequent among females (Sawalha et al., 2010).

Common Substances Involved

The most frequently involved substances in poisonings include analgesics, household cleaning substances, antidepressants, and cosmetics/personal care products (Gummin et al.). Analgesic poisoning has been particularly notable, with a rapid increase in cases over the past decade.

Detailed Insights:

1.     Analgesic Poisoning Trends:

1. The incidence of poisonings involving opioid analgesics has increased significantly over the years. For instance, the rate of opioid-analgesic poisoning deaths nearly quadrupled from 1.4 per 100,000 in 1999 to 5.4 per 100,000 in 2011. This increase has been largely driven by the misuse of prescription opioids such as hydrocodone, morphine, and oxycodone (Chen et al., 2014).

2. In the pediatric population, hospitalizations for opioid poisonings rose nearly two-fold from 1997 to 2012, particularly affecting young children and older adolescents. The annual incidence of hospitalizations for opioid poisonings per 100,000 children aged 1 to 19 years increased from 1.40 to 3.71 during this period (Gaither et al., 2016).

3. The trend in analgesic-related medication errors reported to US poison control centers increased significantly by 82.6% from 2000 to 2009, highlighting the growing issue of analgesic misuse and the need for better management and preventive measures (Eluri et al., 2018).

2.     Household Products and Other Common Substances:

2. Household cleaning substances and personal care products are frequent causes of accidental poisonings, especially in children under five years old. These substances are often involved in unintentional ingestions due to their accessibility and attractive packaging.

3.     Antidepressants:

3. The use of antidepressants in overdose cases has also seen an increase. Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), have become more common in self-poisoning incidents over recent years, reflecting changes in prescribing practices (Staikowsky et al., 2004).

Outcomes

The majority of poisoning cases are managed with supportive care, but a significant number result in severe outcomes, including hospitalization and death. In 2022, 3,255 poisoning-related deaths were recorded, with 80.6% of these deaths directly related to toxic exposure (Gummin et al.).

Geographical Variations

Poisoning incidence and types of substances involved can vary by region and are influenced by local drug availability, industrial activities, and regional healthcare practices.

Global Context

Global Morbidity and Mortality

Poisonings from both legal and illegal substances continue to be significant causes of morbidity and mortality globally. Although the overall mortality rate remains low, the impact on healthcare systems is substantial. Thirty-one percent of cases required management in healthcare facilities, and 6.7% necessitated hospital admission. Notably, fatal poisonings remain rare in children under 12 years old (Gummin et al.).

Emergency Department Visits and Hospital Admissions

Between 2016 and 2019, an estimated 270,000 emergency department visits in the US were related to self-harming medication use, with an additional 1.4 million visits for therapeutic use of medications. Similar rates are observed in other industrialized nations. In children under six, most cases involved unintentional ingestion, whereas most adult fatalities (age 20 and older) were suicidal. Females accounted for a slightly higher percentage of exposures, but males represented a significant portion of fatal ingestions (Gummin et al.).

Regional Trends and Substance Variations

In 2008, poisoning surpassed motor vehicle collisions as the leading cause of injury-related death in the US, with over 102,000 deaths in 2021, primarily involving opioids. Suicide by poisoning is notably prevalent in Scandinavian countries and the UK, while less common in Eastern Europe and Central and South America (Gummin et al.). The most common drug classes involved in poisoning include analgesics (e.g., acetaminophen), opioids, and antidepressants. Regional trends vary; for instance, opioids, acetaminophen, and gamma hydroxybutyrate (GHB) are prevalent in Norway, while benzodiazepines, antidepressants, and antihistamines are common in German ICUs. In Africa and East Asia, pesticides account for more poisoning cases than medications (Gummin et al.).

General Approach to Management

Initial Assessment and Stabilization

• Ensure stabilization of the patient's airway, breathing, and circulation (ABCs).

• Perform a focused history and physical examination to identify the poison and assess the patient's condition (Thompson et al.).

Vital signs are crucial in assessing and monitoring the status of poisoned patients, offering valuable clues to the toxicologic etiology and severity of illness. Although additional components like oxygen saturation and capillary blood glucose are important, this section focuses on traditional vital signs: blood pressure, pulse rate, respiratory rate, and temperature.

Blood Pressure Xenobiotics can cause hypotension through decreased peripheral vascular resistance, myocardial contractility, dysrhythmias, and intravascular volume depletion. Conversely, hypertension can result from CNS sympathetic overactivity, increased myocardial contractility, and increased peripheral vascular resistance. The variability in blood pressure changes often assists in diagnosing poisoning (Hoving et al., 2011).

Pulse Rate The pulse rate provides critical information about the balance between sympathetic and parasympathetic tone. Many xenobiotics that exert therapeutic or toxic effects influence pulse rate, which can also be affected by pain, hyperthermia, or volume depletion. Distinguishing between sympathomimetic and anticholinergic effects can be challenging, as both can cause tachycardia. However, accompanying signs like diaphoresis or bowel sounds can help differentiate them (Dalefield, 2015).

Respiratory Rate Evaluation of respiratory status, including rate, depth, and pattern, is essential in assessing poisoned patients. Hyperventilation may result from CNS stimulants, metabolic acidosis, or pulmonary injury, while CNS depressants can cause bradypnea. Understanding the ventilatory status in the context of the patient's physiologic condition is critical (Larsen & Cummings, 1998).

Temperature Core temperature assessment is vital in managing poisoned patients. Hyperthermia can result from internal heat generation or external factors and may lead to serious complications if not promptly addressed. Severe hyperthermia (>106°F or >41.1°C) requires immediate intervention. Hypothermia, though less immediately life-threatening, also requires rapid and accurate diagnosis and management (Hoving et al., 2011).

Toxidromes Toxidromes are groups of signs and symptoms that result from particular toxins. These syndromes are best described by a combination of vital signs and clinically apparent end-organ manifestations, including changes in mental status, pupil size, peristalsis, skin condition, mucous membranes, and urinary function. Identifying these patterns can aid in diagnosing and managing poisoning cases.

Key Takeaways for Clinical Practice

• Importance of Serial Monitoring: Repeated evaluation of vital signs helps identify patterns and monitor response to treatment.

• Differentiating Toxidromes: Understanding and recognizing toxidromes is crucial for accurate diagnosis and effective management.

• Assessment and Stabilization: Initial assessment should focus on stabilizing vital signs, with continuous monitoring to detect trends and changes.

• Comprehensive Evaluation: A thorough history, physical examination, and meticulous attention to vital signs are essential in identifying the toxicologic etiology and guiding appropriate treatment interventions.

History and Physical Examination

Gathering Information

• Gather information on the substance ingested, the amount, the time of ingestion, and any symptoms presented.

• Look for toxidromes and symptom complexes that help identify specific types of poisoning (Kulig).

Supportive Care

• Provide general supportive care, including oxygen, intravenous fluids, and medications to support cardiovascular and respiratory functions.

• Monitor vital signs and laboratory parameters regularly (Boyle et al.).

Prevention of Poison Absorption

• Use activated charcoal within the first hour of ingestion to prevent further absorption of the poison.

• Consider gastric lavage or whole bowel irrigation in specific cases, based on the type and amount of poison ingested (Goldberg et al.).

Use of Antidotes and Enhanced Elimination Techniques

Antidotes While supportive care is the cornerstone of poisoning treatment, antidotes can be lifesaving for certain poisonings. Administer specific antidotes when indicated—for example, naloxone for opioid poisoning or flumazenil for benzodiazepine overdose. Antidotes should be used judiciously and only when the clinical diagnosis supports their use. They work by various mechanisms, including neutralizing poisons, antagonizing effects, or inhibiting toxic metabolite conversion (McGlone & Teece; Spyker & Minocha).

Enhanced Elimination Techniques In some cases, techniques such as hemodialysis, hemoperfusion, or urinary alkalinization may be employed to enhance the elimination of certain toxins (Yarbrough).

Diagnosis and Diagnostic Studies of Poisoning

Patient History

Though intuitively useful, the history can be unreliable, especially in intentional ingestions. Confirm the history with signs, symptoms, and laboratory data. If the patient cannot provide a reliable history, obtain information from various sources. Check the exposure environment for clues and inquire about over-the-counter medications, traditional or herbal remedies, and dietary supplements (Thanacoody).

Detailed Physical Exam

The physical examination of symptomatic poisoned patients offers invaluable clues. Mental status, vital signs, and pupillary examination are critical, helping classify the patient into physiologic excitation or depression states.

• Physiologic Excitation: This condition can be caused by anticholinergic agents, sympathomimetic agents, central hallucinogenic agents, or states of drug withdrawal.

• Physiologic Depression: This condition can be caused by various substances, including sedative-hypnotic agents, opioids, cholinergic agents, sympatholytics, or alcohol.

• Mixed Physiologic Effects: Seen in polydrug overdoses or exposure to certain metabolic poisons, membrane-active agents, heavy metals, or agents with multiple mechanisms of action.

Various physical findings, such as characteristic odors, pupillary findings, neuromuscular abnormalities, mental status alterations, skin findings, temperature alterations, blood pressure and heart rate alterations, and respiratory disturbances, can assist in diagnosing poisoning (Olson et al.).

Electrocardiography ECG abnormalities can provide diagnostic and prognostic information. An ECG should be performed on all symptomatic patients or those exposed to potentially cardiotoxic agents. Pay attention to QRS and QTc intervals, as many drugs cause sodium or potassium channel blockade (Thanacoody).

Radiographic Studies Imaging is not always required but can be useful in certain situations, such as visualizing radiopaque toxins or ingested drug packets (Vale & Bradberry).

Toxicology Screens Toxicology screening is rarely necessary for asymptomatic patients or those with consistent clinical findings and medical history. However, screening for acetaminophen and salicylates is recommended for uncertain histories or intentional poisonings. Urine drug screens can detect various substances, but comprehensive toxicology screening should be reserved for severe or unexplained toxicity or legal implications (Lee et al.).

Other Laboratory Studies Laboratory abnormalities characteristic of specific agents should guide further testing. Initial tests should include serum electrolytes, renal function, and glucose measurements, with additional tests based on the patient's condition (Vale et al.).

Poisoning Management

Decontamination

Decontamination, performed soon after exposure, can prevent poison absorption. Methods include irrigation for topical exposures and activated charcoal for ingestion. Decontamination methods vary by exposure type and specific toxins (Hoving et al.).

Supportive Care

Supportive care is crucial and often sufficient for recovery. This supportive care includes managing airway protection, hypotension, hypertension, arrhythmias, seizures, agitation, and hyperthermia, with specific treatments based on the patient's condition and the toxins involved (Singh et al.).

Initial Management of Patients with a Suspected Exposure

Managing Acutely Poisoned or Overdosed Patients

For over five decades, medical toxicologists have emphasized treating the patient rather than the poison. An organized, rapid clinical management plan is essential, focusing on the patient's clinical status rather than solely on the ingredients listed on the product containers.

Evaluation and Management of Altered Mental Status (AMS)

AMS is defined as the deviation of a patient's sensorium from its baseline, including hyperactive, agitated conditions and depressed levels of consciousness. Initial bedside assessment should include airway patency, adequacy of breathing, pulse strength and rate, blood pressure, and rectal temperature. Continuous rhythm monitoring and a 12-lead electrocardiogram (ECG) are essential to identify dysrhythmias related to toxic exposures.

Specific Treatments

Within the first 5 minutes of managing a patient with AMS, administer the following if indicated and not contraindicated:

• Supplemental Oxygen: To treat xenobiotic-induced hypoxia.

• Hypertonic Dextrose: 0.5 to 1.0 g/kg of D50W for an adult.

• Thiamine: 100 mg IV for an adult to prevent Wernicke encephalopathy.

• Naloxone: 0.04 mg IV with upward titration for opioid-induced respiratory compromise.

Gastrointestinal Decontamination

Decisions regarding GI decontamination should be based on the specifics of the ingestion, including the quantity, formulation, time since exposure, concurrent ingestions, and the patient's condition. Based on these factors, activated charcoal, orogastric lavage, and whole-bowel irrigation (WBI) with polyethylene glycol electrolyte solution (PEG-ELS) are considered.

Eliminating Absorbed Xenobiotics

After deciding on decontamination, assess the applicability of techniques to eliminate absorbed xenobiotics. These include:

• Alkalinization of Urine: Enhances renal excretion of acidic xenobiotics.

• Hemodialysis: Used for patients who overdose on salicylates, methanol, ethylene glycol, lithium, valproic acid, and other dialyzable substances.

• Hemoperfusion: Useful for substances like theophylline, phenobarbital, and carbamazepine, though now less common in the US.

Disposition

Disposition is based on toxicity severity. Mild cases can be observed in the emergency department, while moderate to severe cases require hospital admission or ICU care. All intentional overdoses need a psychiatric assessment before discharge. Criteria for ICU admission include severe respiratory, cardiovascular, or neurological impairment.

Criteria for Disposition

Mild Cases:

• Patients with mild symptoms can typically be managed and observed in the emergency department. They can be discharged once their condition stabilizes and they show no signs of deterioration (Adams et al.).

Moderate to Severe Cases:

• Hospital admission is warranted for patients with moderate to severe symptoms, including significant changes in vital signs, mental status, or laboratory findings. Continuous monitoring and supportive care are essential to manage these patients effectively (Eizadi-Mood et al.).

ICU Admission Criteria:

• Severe Respiratory Impairment: Patients who require mechanical ventilation or are experiencing significant respiratory distress should be considered for ICU admission.

• Cardiovascular instability: Patients with severe hypotension, arrhythmias, or requiring vasoactive drugs for blood pressure support.

• Neurological impairment: Patients with severe altered mental status, seizures, or coma (Wang et al.).

Psychiatric Assessment:

All patients with intentional overdoses must undergo a psychiatric evaluation before discharge to address underlying mental health issues and prevent future episodes. This evaluation is crucial for providing appropriate psychiatric care and support (Poynton et al.).

Additional Resources

Poison Control Centers Contact Information

Regional poison control centers provide consultation for poisoning cases. In the US, they can be reached at 1-800-222-1222. Poison center contact information worldwide is available separately (Vassilev & Marcus).

Summary and Recommendations

Toxicology Consultation:

• Seek help from poison control centers or medical toxicologists (Hoving et al.).

Avoid Unnecessary Interventions:

• Weigh intervention risks against benefits (Ghannoum & Roberts).

Initial Stabilization:

• Prioritize stabilization for compromised airway, gas exchange, or hemodynamics (Singh et al.).

Comprehensive History:

• Obtain a thorough exposure history, considering over-the-counter drugs and remedies (Thanacoody).

Detailed Physical Examination:

• Perform comprehensive exams for toxidrome signs (Olson et al.).

Diagnostic Testing and Imaging:

• Focused evaluations are conducted based on clinical status and suspected toxins (Vale & Bradberry).

Specific Drug Testing:

• Screen for specific toxins when history is uncertain, or toxicity is unexplained (Lee et al.).

Supportive Care and ICU Criteria:

• Provide supportive care and admit patients based on clinical criteria (Wang et al.).