Poisoning (General Principles of Treatment)

The majority of poisoning cases are related to mistakes in dosage. The concentration of the substance over time determines the dosage. Excessive exposure to usually harmless compounds can result in toxicity. Some poisonings occur due to being exposed to chemicals that are toxic at all concentrations. Poisoning is distinct from hypersensitivity and idiosyncratic reactions, which are unexpected and unrelated to dosage, and intolerance – which is a toxic reaction to a normally harmless dose of a chemical.

Poisoning is most usually caused by ingestion. It may also be caused through inhalation, injection, or contact with bodily surfaces (e.g., through the skin, eye, mucous membranes). Many widely used non-food chemicals are typically non-toxic. Despite this, practically any item can be harmful if consumed in large quantities.

Consumable Substances That Are Usually Not Dangerous

Accidental poisoning is prevalent in young toddlers, who are interested and swallow stuff indiscriminately despite terrible tastes and odours. Often, just one toxin is implicated. Poisoning is particularly common among older children, teenagers, and adults who attempt suicide. Numerous medicines, especially acetaminophen, alcohol, and other over-the-counter (OTC) medications, may be included in these types of poisonings. Accidental poisoning in the elderly might occur as a result of disorientation, poor vision, mental disability, or repeat prescriptions for the same medicine by various doctors. Disabling drugs (e.g., scopolamine, gamma-hydroxybutyrate, benzodiazepines) typically have sedative, amnestic, or both characteristics. 

Types of Poisoning

• Poisons that can be ingested

• Poisons that can be inhaled

• Poisons that can be taken on the skin

• Poisons that can get in our eyes

Poisoning Diagnosis

The most typical signs of poisoning include respiratory or CVS depression, impairment of consciousness, dehydration owing to diarrhoea/vomiting, convulsions, hypothermia, arrhythmia, convulsions, and commas. As a result, a diagnosis is determined based on the symptoms of poisoning exhibited. The diagnosis is based on the following factors: 

1. History

It is imperative to obtain and record information such as name and kind of drug, time of drug intake, co-administration of other drugs such as alcohol, method of ingestion, and amount of drug. This provides information regarding the patient’s clinical status, stability, and drug clearance.

2. Physical Examination 

This includes monitoring breathing, airway patency, circulation, mental state, pupil size, temperature, blood pressure, blood glucose, pulse, ECG, muscle tone, and reflexes. Following that, evidence in the form of a suicide note or a container of poisons is recorded. The case is evaluated depending on the source of the poisoning. 

The homicidal, suicidal, and criminal poisoning is reported to the police and a forensic toxicologist. Depressed states are sometimes caused by antipsychotics, antidepressants, antiarrhythmics, adrenergic blockers, carbamates, narcotics, sedatives, and hypnotics. However, agitated states are caused by caffeine, cocaine, ergot alkaloids, antihistamines, and antiparkinsonian drugs.

3. Laboratory Evaluation 

The oxygen level in the blood, arteries, plasma osmolarity, and oxygen binding capability to haemoglobin are all measured using appropriate procedures.

4. Toxicological Testing 

This method offers direct proof of toxicity in the body. Before completing such screening, the patient must be given first and main supporting measures. This screening procedure aids in the selection of an appropriate antidote, reduces poison absorption, and eradicates the problem with subsequent care.

Iron Poisoning Diagnosis

Iron poisoning should be evaluated in mixed ingestions (since iron is widespread) and in tiny children with iron availability and unexplained metabolic acidosis or severe or hemorrhagic diarrhoea. Siblings and playmates of little children who have consumed iron should also be checked since children frequently share their food and toys.

To confirm intake, an abdominal x-ray is frequently indicated. It identifies whole iron pills or iron agglomerate but ignores chewed and digested tablets, fluid iron treatments, and iron with multivitamin preparations. Serum iron, electrolytes, and pH are measured three to four hours after administration. If any of the following symptoms follows suspected consumption, toxicity is assumed:

• Vomiting and stomach ache

• Serum iron levels more than 350 mcg/dL (63 micromol/L)

• Iron may be seen on X-rays

• Unknown cause of metabolic acidosis

These iron levels may suggest poison. However, iron levels alone can not predict toxicity precisely. Total iron-binding capacity is frequently inaccurate and ineffective in diagnosing severe poisoning, and it is not recommended. The most reliable method is to test blood iron, bicarbonate, and pH levels sequentially (with anion gap computation); these findings are assessed together, and the results are connected with the patient’s clinical situation. Toxicity is indicated, for example, by increased iron levels, metabolic acidosis, worsening symptoms, or, more commonly, any combination of these findings.

Initial step in poisoning treatment

If the victim ingested poison, provide him or her with some fresh air as soon as possible. If indeed the individual has poison on their skin, remove any clothes that have come into contact with the poison. Rinse skin for 15 to 20 minutes with running water. If the person has poison in their eyes, rinse them for 15 to 20 minutes with running water.

Poisoning Management

The basic approach to the poisoned patient can be split into six phases: 

(1) stabilisation; 

(2) laboratory evaluation; 

(3) cleaning of the gastrointestinal system, skin, or eyes; 

(4) delivery of an antidote; 

(5) toxin elimination augmentation

(6) observation and disposal.

Conclusion

All individuals with gastroenteritis that is more severe than moderate are admitted to the hospital. To chelate free serum iron, suffering from chronic toxicity (metabolic acidosis, shock, acute diarrhoea, or high serum level > 500 mcg/dL [89.5 micromol/L]) are given IV deferoxamine. Deferoxamine is administered intravenously at rates of up to 15 mg/kg/h, titrated until hypotension is achieved. Patients taking deferoxamine require IV hydration since both deferoxamine and iron toxicity can lower blood pressure.