Cocaine Toxicity in Emergency Medicine Clinical Presentation

The factors addressed below focus on drug use and supplement elements of the standard medical-history interview. A drug history is indicated in all patients and should be particularly complete in those presenting with drug reactions, acute anxiety, or other psychological problems, as well as in those with acute cardiovascular, pulmonary, or neurologic symptoms. If the patient is confused or unresponsive, query relatives, friends, or witnesses about antecedent activities, and seizures or syncope. This is crucial, especially if patients are carrying cocaine in their body, because they often have no stigmata of drug abuse.

History of present illness can be determined as follows:

• What drug was used?
• When was the substance used and for how long was it used? What is the patient's tolerance, cross-tolerance, and reverse tolerance? Is evidence of a withdrawal syndrome present?
• What was the total amount of cocaine used? How does this compare with the amount generally used? How long after cocaine use were symptoms noted?
• By what route was it taken? For how long has this route been used?
• Does the patient have symptoms such as pain (eg, chest, abdominal), dyspnea, altered tactile sensation (eg, cocaine bugs, Magnan sign), or hallucinations (eg, lilliputian hallucination, halo lights around objects)? Was altered mental status or seizure reported?
• Is the patient pregnant (eg, decreased plasma cholinesterase)?
• Is the patient a victim of domestic violence? (Substance abuse may develop or worsen as a result of domestic violence. Accordingly, it is appropriate to consider domestic violence when evaluating a patient for alcohol intoxication or drug toxicity and overdose.)

Review of systems is as follows:

• Is the effect of cocaine increased secondary to liver disease or CHF? Is evidence of MI or coronary artery disease present? Is evidence of a dysrhythmogenic substrate (eg, myocarditis, cardiomyopathy, WPW) present?
• When considering the extent of the review of systems (ROS), be mindful of the wide range of organ systems that cocaine and its routes of administration can affect.

Medication and drug use history can be determined as follows:

• What is the patient's average daily use? What is his or her history of cocaine and other drug use? (The mechanism of fatality differs for long-term cocaine users.)
• Does the patient use tobacco (ie, does he or she have increased risk for atherosclerosis and coronary vasospasm)? How many packs does the patient smoke per day?
• Does the patient use alcohol (ie, is cocaethylene formation possible)? If so, did the patient drink before or during cocaine uses? How much alcohol was consumed?
• What other substances were used? How much was consumed? What route of intake was used?
• Does the patient have any other drug addictions? Were any drug combinations taken or were drugs taken to increase, prolong, or decrease the effects of cocaine?
• Could medications taken by the patient potentiate the effects of cocaine? Is the patient in withdrawal?
• What prompted the visit to the ED? DAWN data for 1998 reflect the reasons for cocaine-related ED visits: unexpected reaction (21.9%), overdose (15.1%), chronic effects (13.8%), accidental injury (4.9%), withdrawal (3.2%)
• Does the patient want help in coping with cocaine use? DAWN data from 2004 reported that 46% of patients presenting to EDs did so for detoxification.^[19]

Multisystem effects of cocaine

Suspect cocaine use in patients, especially young patients, with altered mental status, new-onset seizure, hypertension, chest pain, myocardial ischemia or infarction, dyspnea, intracranial hemorrhage, epistaxis, or psychiatric illness. Pay particular attention to the assessment of vital signs and to a detailed examination of the cardiac, pulmonary, and neurologic systems, as listed below.

Association with trauma

Trauma is associated with use of cocaine. Cocaine can cause agitation, paranoia, distractibility, distorted perception, and depression. All of these may increase the likelihood of violence, suicide, or accidental injury. When cocaine is combined with alcohol, the frequency of ED presentations is substantially greater than when cocaine is used alone.

Differential diagnosis

Cocaine overdose may resemble serotonin syndrome, lithium toxicity, cyclic antidepressants toxicity, neuroleptic malignant syndrome (NMS), thyroid storm, and other hyperadrenergic states.

Consider the diagnosis of phenytoin toxicity in cocaine users who present with lethargy or cerebellar findings. Signs of phenytoin toxicity are correlated with serum levels and include nystagmus, ataxia, dysarthria, lethargy, hypotension, and coma.

Vital signs and general presentation

Although bradycardia is reported as an initial effect, the classic presentation of a patient under the influence of cocaine is tachycardia and hypertension.

When Hollander and Hoffman reviewed the literature concerning 91 patients with cocaine-induced MI, they found that as many patients were bradycardic as tachycardic, and one third were hypertensive.^[20] As a result of pathologic vasoconstriction, a patient with hemorrhagic trauma may present with a normal mean arterial pressure.

Cocaine causes pathologic vasoconstriction, thus hypovolemia secondary to hemorrhage may be delayed in recognition because the patient maintains a normal mean arterial pressure. This combination of pathophysiologic factors, coupled with delayed recognition, increases the potential for cerebral insult.^[21]

Chronic cocaine use downregulates adrenergic receptors and decreases endogenous catecholamine stores in the heart. This may affect the patient's presentation, as was observed in a study of patients admitted to a trauma service. Of 84 patients with a systolic BP less than 100 mm Hg, 45% had relative bradycardia (heart rate < 100 bpm). Toxicology data were obtained infrequently, but when determined, they demonstrated that cocaine was more frequently reported in patients with bradycardia (76%) than in those with tachycardia (26%).

The patient's skin may be cool and clammy though the patient is hyperthermic; therefore, obtaining a rectal temperature is advisable.

Cardiovascular findings

Cardiopulmonary complaints are the most common presenting manifestations of cocaine abuse and include chest pain (frequently observed in long-term use or overdose), MI, arrhythmia, and cardiomyopathy.

In individuals with cocaine-associated MI, median times to the onset of chest pain vary with the route or form of cocaine use: 30 minutes for intravenous use, 90 minutes for crack, and 135 minutes for intranasal use.

Chest pain may be observed in as many as 40% of patients presenting to the ED after admitting to cocaine use. In a study of urban and suburban EDs, cocaine or its metabolites were found in 17% of patients presenting with chest pain. This starkly contrasts with the pretest estimated prevalences of 2-4% for the suburban study site and 10% for the urban sites. The mean age of patients with chest discomfort and positive assays for cocaine was 36 years.

Include cocaine use in the differential diagnosis of any acute vascular problem.

Vascular spasm may cause blindness, renal infarction, limb ischemia, and intestinal ischemia. Limb ischemia may occur after intra-arterial injection. This may be accidental, or intentional due to the unavailability of veins because of sclerosis secondary to repetitive puncture, or due to the desired effects from arterial injection.

Aortic dissection may also be associated with cocaine use.

Hypertension occurs frequently.

Other cardiovascular findings include the following:

• Dysrhythmia (premature ventricular contractions [PVCs], supraventricular tachycardia [SVT], ventricular tachycardia [VT], and ventricular fibrillation [VF])
• Vasomotor collapse
• High-output heart failure

Respiratory findings

As reported in the literature, the primary acute pulmonary complaint associated with cocaine use is cough with black sputum (44% of patients). Chest pain is secondary, affecting 38% (pleurisy in 64% of patients with pain). Of patients with new-onset asthma who present to large urban EDs, 36.4% have a urine screen positive for cocaine (compared with 13.6% of control patients without asthma). Hemoptysis accounts for 25% of pulmonary complaints, the result of pulmonary and bronchial constriction and ischemia resulting in interstitial and alveolar hemorrhage.

"Crack lung," a syndrome usually occurring 1-48 hours after cocaine smoking, is a hypersensitivity pneumonitis. It consists of the constellation of chest pain, cough with hemoptysis, dyspnea, bronchospasm, pruritus, fever, diffuse alveolar infiltrates without effusions, and pulmonary and systemic eosinophilia.

Barotrauma, such as pneumothorax and pneumomediastinum, may result from smoking or snorting cocaine and then performing a prolonged Valsalva maneuver to increase the effect of the drug, or from coughing against a closed glottis. The increased airway pressure ruptures an alveolar bleb, and free air dissects along peribronchial paths into the mediastinum and pleural cavities.

The incidence of respiratory complaints in people who use cocaine is not known. The following respiratory toxic reactions are reported in association with cocaine use:

• Barotrauma (eg, pneumothorax, pneumopericardium, pneumomediastinum)
• Pulmonary hemorrhage or infarction
• Diffuse alveolar hemorrhage
• Pulmonary edema
• Wheezing secondary to bronchial muscle constriction
• Airway irritation via damage to bronchial epithelial cells, and stimulation of vagal receptors, inducing bronchospasm, exacerbating asthma
• Eosinophilic lung disease
• Recurrent transient pulmonary infiltrates with peripheral eosinophilia
• Chronic diffuse interstitial pneumonia with mild fibrosis
• CNS stimulant effects (eg, neurogenic pulmonary edema, respiratory depression in overdose or postictal state, abnormal hypoxic response in infants of cocaine-abusing mothers, sudden infant death syndrome (SIDS), and pulmonary hypertension)
• Crack lung or transient pulmonary infiltrates
• Nasal septum perforation and/or aspiration
• Bronchiolitis obliterans organizing pneumonia
• Granulomatosis
• Sinusitis
• Epiglottitis
• Bronchitis
• Cellulose granulomas in lung
• Panlobular emphysema
• Needle or other foreign body aspiration
• Alveolar accumulation of carbonaceous material
• Airway burns or tracheal stenosis
• Tachypnea, irregular breathing
• Respiratory arrest
• Acute lung injury (noncardiogenic [increased permeability] pulmonary edema)

Eyes, nose, mouth, and throat findings

Signs include reactive mydriasis, nystagmus (generally vertical but may be bidirectional), epistaxis, atrophic mucosa, ulcerated nasal septa, perforations, acute inflammation or scarring of the tongue, epiglottis, vocal cords, and trachea.

Hoffman and Reimer list a variety of ophthalmologic complications from cocaine use^[22] :

• Cocaine-associated cerebral vasculitis, which may produce gradual decrease in visual acuity or acute blindness
• Central retinal artery occlusion
• Blurring of vision
• Endophthalmitis from systemic or local infection
• Foreign-body granuloma
• Foreign-body embolization
• Optic neuropathy, resulting from chronic sinusitis due to intranasal cocaine use and manifesting as decreased visual acuity
• Corneal ulcerations secondary to direct instillation of cocaine into the conjunctival fornix and vision loss caused by crack-induced corneal ulceration from direct irritation of the smoke, cocaine-induced epithelial disruption, and repeated mechanical disruption from rubbing
• Torticollis, trismus, and laryngospasm may endanger the airway.

GI findings

Vomiting, diarrhea, and hyperactive bowel sounds may be present. When evaluating a patient with a history of cocaine use and a complaint of abdominal pain, consider mesenteric ischemia in the differential diagnosis. Patients with abdominal pain must also be evaluated for renal infarction.

The vascular supply to the intestine has many alpha-adrenergic receptors, and their stimulation may cause mesenteric ischemia. The clinical presentation of mesenteric ischemia includes abdominal pain and possibly tenderness, nausea, vomiting, and bloody diarrhea. Muscarinic receptor blockade results from high concentrations of cocaine, with anticholinergic effects on gastric motility that predisposes the person to ulceration from prolonged exposure to acid.

Skin, thermoregulatory, and renal findings

Patients may have sores or linear excoriations; crack pipe burns of the fingers or thumbs; thermal burns of the face and upper airway; and redness, swelling, and tenderness (secondary to phlebitis, vasculitis, cellulitis, and abscess formation).

Search for track marks in the usual sites, such as the antecubital fossae, and unusual sites, such as under the tongue and on top of the feet.

Excoriations from pruritus or hallucinations of crawling insects associated with cocaine use may also be found.

Cocaine affects the anterior hypothalamus, which increases the thermoset point. Agitation secondary to intoxication or withdrawal results in increased motor activity, which causes increased heat production.

Rule out occult infections in patients with fever.

Evaluate patients with abdominal or back pain for renal infarction.

Neurologic and psychiatric findings

Altered sensorium and acute seizures are the most common cocaine-associated neurologic syndromes observed in the ED, accounting for 52% of related presentations. Other cocaine-related neurologic processes are toxic encephalopathy, ischemic and hemorrhagic stroke, neurogenic syncope, and movement disorders. Use of cocaine also decreases rapid eye movement (REM) sleep.

Seizures, which can produce hyperthermia and lactic acidosis, are a major determinant of lethality.

About 3-4% of all strokes occur in patients aged 15-45 years. Cocaine is a common cause of stroke in young patients. Cocaine-induced hypertension may lead to hemorrhage from a cerebral aneurysm or ruptured arteriovenous malformation (AVM).

Extrapyramidal phenomena and other movement disorders, though uncommon, are reported in association with cocaine use. These effects are collectively referred to as "crack dancing." In a patient without a history of neuroleptic use such a presentation may be confusing to the ED physician.

Headaches, some potentially resulting from inhibited serotonin reuptake, are common in people who use cocaine, whereas cerebral vasculitis is rare.

Approximately 60% of people who regularly use cocaine report psychiatric complications of their drug use, and 18% have had visual or tactile hallucinations; a sensation of something crawling on the skin is most common.

Psychiatric complications commonly associated with cocaine use include anxiety, depression, paranoia, delirium, psychosis, and suicide. Toxic psychosis might be misdiagnosed as paranoid schizophrenia.

A crash follows cocaine binging and may result in extreme exhaustion (may be severe enough that the patient appears unresponsive), anxiety, psychomotor retardation, and increased appetite. Of note, the most common problem during a crash is depression that may reach suicidal proportions.

In withdrawal, depletion of dopamine and norepinephrine leads to dysphoria, depression, and drug craving.

In short, neurologic and psychiatric findings may include the following:

• Normal sensorium
• Altered mental status (a change in the level of consciousness or the content of consciousness)
• Confusion
• Restlessness
• Severe agitation
• An increase in purposeless psychomotor activity that may be exacerbated by nonspecific stimulation in the setting of cocaine use (commonly called cocaine leaps)
• "Overamped" or "wired" behavior
• Paranoia
• Delirium (a florid abnormal mental state characterized by disorientation, fear, and irritability with misperception of sensory stimuli)
• Headache
• Tremor
• Depression and extreme exhaustion associated with withdrawal following a binge

Renal findings

Vascular spasm may cause renal infarction. Cocaine may also exacerbate renal susceptibility to rhabdomyolysis by causing hyperthermia, vasoconstriction, and/or hypotension secondary to hypovolemia or MI.

Endocrine and metabolic findings

Acute toxic effects of cocaine may include acidosis, hyperkalemia, and hyperglycemia. Prolonged use of sympathomimetics, such as in a cocaine binge, may result in hypoglycemia.

Musculoskeletal findings

Cocaine use is among the drug-related causes of intrinsic muscle weakness. Wilson and Hobbs report a patient with Cori disease in whom cocaine unmasked subclinical skeletal muscle weakness, causing prolonged respiratory muscle insufficiency. Cocaine has also been implicated as a cause of impairment of neuromuscular transmission in a patient with myasthenia gravis.

Body cavity search

Packets of illicit drugs may be ingested or inserted into body cavities by "swallowers," "internal carriers," "couriers," or "mules" to intentionally transport drug, a practice called body packing. Another practice, body stuffing, involves swallowing relatively small amounts of loosely wrapped drug, or secreting packets in body cavities because of the fear of arrest. With suspicion of body packing or body stuffing, perform careful cavity searches of the rectum and vagina. Continued drug absorption is likely if toxicity continues for more than 4 hours.

Altered mental status

A number of etiologic possibilities are possible, including toxic (eg, drug intoxication, withdrawal), metabolic, structural or traumatic, infectious, epileptic, or psychogenic causes.

A simple toxicologic presentation is rare. Therefore, it is frequently necessary to differentiate agitation secondary to various intoxicants, withdrawal, or possibly both. In the agitated patient with extreme irritability, irrationality, and destructiveness, intoxication or withdrawal should be considered.

Cocaine causes a sympathomimetic toxidrome, as do amphetamines, hallucinogens, and PCP; PCP causes the most persistent psychophysiologic reactions. Withdrawal from alcohol or sedative-hypnotics may cause the triad of hyperthermia, agitated delirium, and seizures.

Phases of acute cocaine toxicity

Three phases are reported. In fatal cases, the onset and progression are accelerated, with convulsions and death frequently occurring in 2-3 minutes, though sometimes in 30 minutes. Cocaine stimulates the CNS in rostral-to-caudal fashion, with findings varying with the time since drug use.

Phase I (early stimulation) is as follows:

• CNS findings - Mydriasis, headache, bruxism, nausea, vomiting, vertigo, nonintentional tremor (eg, twitching of small muscles, especially facial and finger), tics, preconvulsive movements, and pseudohallucinations (eg, cocaine bugs)
• Circulatory findings - Possible increase in BP, slowed or increased pulse rate (possibly with ventricular ectopy), and pallor
• Respiratory findings - Increase in rate and depth
• Temperature findings - Elevated body temperature
• Behavioral findings - Euphoria, elation, garrulous talk, agitation, apprehension, excitation, restlessness, verbalization of impending doom, and emotional lability

Phase II (advanced stimulation) is as follows:

• CNS findings - Malignant encephalopathy, generalized seizures and status epilepticus, decreased responsiveness to all stimuli, greatly increased deep tendon reflexes, and incontinence
• Circulatory findings - Hypertension; tachycardia; and ventricular dysrhythmias (possible), which then result in weak, rapid, irregular pulse and hypotension; and peripheral cyanosis
• Respiratory findings - Tachypnea, dyspnea, gasping, and irregular breathing pattern
• Temperature - Severe hyperthermia (possible)

Phase III (depression and premorbid state) is as follows:

• CNS - Coma, areflexia, pupils fixed and dilated, flaccid paralysis, and loss of vital support functions
• Circulatory - Circulatory failure and cardiac arrest (VF or asystole)
• Respiratory - Respiratory failure, gross pulmonary edema, cyanosis, agonal respirations, and paralysis of respiration

The National Institute on Drug Abuse (NIDA) estimates that 10% of individuals who begin using cocaine progress to serious, heavy use. After having tried cocaine, people cannot predict the extent to which they continue using the drug. According to 1999 DAWN data, patients visiting EDs for a drug-related cause provide the following reasons for using cocaine:

• Dependence (49%)
• Recreational use (37.6%)
• Other psychic effects (19.7%)
• Suicide (8.7%)

A positive family history of substance abuse is related to the speed of developing dependence on cocaine and an earlier age of onset.

Type A and type B dependency

Evidence suggests that cocaine dependence, similar to alcoholism, may have 2 subtypes, A and B (ie, type I and type II in the literature on alcoholism typology). Type A persons may develop cocaine dependence as a function of environmental influences, whereas type B persons may have certain premorbid risk factors that predispose them to a virulent form of cocaine abuse. Ball et al studied 399 patients with cocaine abuse or dependence in the first multidimensional subtyping study of cocaine users.^[23] The most common presentation, observed in 67%, was type A. Women and African Americans most commonly had type A dependency, whereas men and whites most commonly had type B dependency.

Compared with persons with type A dependency, those with type B dependency had more severe abuse of alcohol and other drugs, addiction-related psychological impairment, antisocial behavior, and comorbid psychiatric problems.

Persons with type B dependency were more likely to be separated or divorced, to live alone or in an unstable situation, to have a family history of substance abuse, and to have had greater severity of childhood disorder than individuals with type A dependency. They also scored higher than those with type A dependency in assessments of sensation seeking, aggression, criminality, and violence.

Those with type B dependency had an early age of onset for antisocial personality disorder and early age of first use, first binge, first regular use, and first daily use of cocaine and alcohol. The quantity, frequency, duration, and severity of cocaine abuse and adverse effects (eg, loss of consciousness, chest pain, misperceived reality, violence, and use to relieve to stress) are greater with type B than with type A.

Although the groups do not differ in family history for psychiatric disorders, people with type B dependency had lifetime histories of major depression, suicide attempts, and total treatment episodes for psychiatric disorders as well as for abuse of alcohol and other drugs that were significantly greater than those with type A dependency.

No significant differences were found between the subtypes in terms of employment, education, referral source, number of close friends, age, time between the first use and the onset of symptoms of dependence, route of use, previous periods of abstinence from alcohol or other drugs, or the number of strategies used to control use.

Mental disorders

Rivara et al maintain that one half of those who abuse illicit drugs also have a mental disorder. Indeed, cocaine users, along with persons with alcoholism and those who abuse opiates, have elevated rates of antisocial personality, depression, anxiety, and polysubstance abuse. These traits also have been found in their first-degree relatives.^[24]