Emergency Medicine Flashcards
What is the most common cause of cardiac arrest in a child? Uncommon cause? Survival?
-
Lack of oxygen supply to the heart secondary to a pulmonary problem, respiratory arrest, shock
- Choking, suffocation, airway/lung disease, near drowning
- Uncommon cause: heart disease
- Chances for survival increase dramatically if CPR & advanced life support started quickly
What are the essentials of CPR?
- Airway
- Breathing
- Circulation
How do you expose an airway?
- First priority in resuscitation
- Most common obstruction: tongue
- Head-tilt method
- Jaw-thrust method
- Neck or cervical spine injury
How do you evalulate breathing?
-
Look. Listen. Feel.
- Look for rise & fall in chest
- Listen for exhaled air
- Feel for exhaled airflow
- Rescue breathing if spontaneous absent
How do you evaluate circulation?
- Need for chest compressions determined after 2 rescue breaths
- Pulse assessment
- Infants: brachial artery
- Children: carotid artery
- Chest compressions: asystole, bradycardia
What is the definition of Shock?
- Inadequate delivery of O2 & metabolic substrates to meet the metabolic demands of tissues
- Normal or decreased BP
What are the 3 degrees of Shock?
-
Compensated
- Normal BP & CO, adequate tissue perfusion
- Maldistributed blood flow
-
Decompensated
- Hypotension, low CO
- Inadequate tissue perfusion
-
Irreversible
- Cell death, refractory to medical treatment
What are the 3 categories of Shock?
- Hypovolemic
- Septic
- Distributive
What is hypovolemic shock?
- Most common cause of shock in children
- Decreased circulating blood volume
- Hemorrhage, dehydration
- Amt volume determines compensation
- Endogenous catecholamines
- Volume loss >25% = decompensated shock
What is septic shock?
- Secondary to inflammatory response to microorganisms & toxins, abnormal blood dist.
-
Hyperdynamic stage
- Normal/high CO, bounding pulses, warm extremities, wide pulse pressure
-
Decompensated stage
- Follows hyperdynamic stage
- Impaired mental status, cool extremities, diminished pulses
What is distributive shock?
-
Distal pooling of blood or fluid extravasation
- Anaphylactic or neurogenic shock
- Medications/toxins
- Types
- Anaphylactic shock
- Neurogenic shock
- Cardiogenic shock
What is anaphylactic shock?
Extravasation of intracellular fluid from permeable capillaries
- Acute angioedema of the upper airway
- Bronchospasm
- Pulmonary edema
- Urticaria
- Hypotension
What is neurogenic shock?
- Secondary to spinal cord transection/injury
- Characterized by:
- Total loss of distal sympathetic CV tone
- Hypotension from pooling of blood w/i the vascular bed
What is cardiogenic shock?
- CO limited b/c of primary cardiac dysfunction
- Causes
- Dysrhythmias (supraventricular tachy)
- Congenital heart disease
- Impaired LV outflow
- Cardiac dysfunction after cardiac surgery
- Clinical features
- Signs & symptoms of CHF
Recognition of shock may be difficult because…..
- Presence of compensatory mechanisms
- Prevent hypotension until 25% of intravascular volume lost
- Index of suspicion for shock must be high
What are 6 historical features that may suggest the presence of shock?
- Severe vomiting & diarrhea
- Trauma w/ hemorrhage
- Febrile illness (esp immunocompromised pt)
- Symptoms of CHF
- Exposure to known allergic antigen
- Spinal cord injury
Physical exam of a patient in shock?
- BP may be normal (initial hypovolemic/septic)
- Tachycardia (before BP changes)
- Tachypnea (compensation metabolic acidosis)
- Mental status changes (poor cerebral perfusion)
- Capillary refill prolonged (cool/mottled extrem)
- Peripheral pulses bounding
Important laboratory studies for shock?
- CBC - blood loss & infection
- Electrolytes - metabolic acidosis, electrolyte ab
- BUN & creatinine - renal function/perfusion
- Ca & Glu - metabolic derangements
- Coagulation factors - DIC
- Toxicology screens - poisoning
How is shock managed?
Resuscitation? Medications?
- Initial resuscitation (ABCs)
- Supplemental O2
- Early endotracheal intubation
-
Vascular access w/ fluid resuscitation
- 20 mL/kg bolus of nl saline/LR
-
Restore intravascular volume
- IV crystalloid/colloid
-
Inotropic & vasopressor meds
- Dobutamine, dopamine, epinephrine
- Metabolic derangements treated
- Metabolic acidosos, hypocalcemia, hypoglycemia
- Broad spectrum abx for septic shock
- Blood products for hemorrhage
- FFP for DIC
Trauma is the leading cause of death in children older than _____ year of age.
______ are the leading cause of trauma.
1 year of age
Motor vehicle accidents
How is a child’s response to trauma unique?
- Head injuries common (larger % of body mass)
- Neck shorter & supports greater weight
- Rib cage more pliable, greater energy transmitted to spleen & liver
- Growth plates = weak epiphyseal-metaphyseal junction, ligaments stronger than growth plate
- Injury to the growth plate is highest risk
What is the primary survey in trauma?
- w/i 5-10 min of arrival in the ER
-
ABCDEs
- Airway
- Breathing (100% O2)
- Circulation (control hemorrhage)
- Disability (Glasgow Coma Scale)
- Exposure/Environmental control
Glascow Coma Scale in Verbal Patient
- Eye opening
- Best motor response
- Best verbal response
-
Eye opening
- Spontaneously (4)
- Response to voice (3)
- Response to pain (2)
- No response (1)
-
Best motor response
- Obeys commands (6)
- Localizes pain (5)
- Flexion withdrawal (4)
- Decorticate posturing (3)
- Decerebrate posturing (2)
- No response (1)
-
Best verbal response
- Oriented/appropriate (5)
- Disoriented conversation (4)
- Inappropriate words (3)
- Incomprehensable words (2)
- No response (1)
Glascow Coma Scale in Nonverbal Patient (Child)
- Eye opening
- Best motor response
- Best verbal response
-
Eye opening
- Spontaneously (4)
- Response to voice (3)
- Response to pain (2)
- No response (1)
-
Best motor response
- Normal movements (6)
- Localizes pain (5)
- Flexion withdrawal (4)
- Flexion abnormal (3)
- Extension abnormal (2)
- No response (1)
-
Best verbal response
- Cries normally, smiles, coos (5)
- Cries (4)
- Inappropriate crying & screaming (3)
- Grunts (2)
- No response (1)
What are 3 adjuncts to the primary survey?
-
ECG monitoring
- Dysrhythmias (cardiac injury)
- Pulseless electrical activity (cardiac tamponade, tension pneumo, hypovolemia)
-
Urinary catheter & NG tube
- Monitor UOP, reduce abd distension
-
Diagnostic studies
- Radiographs: cervical spine, chest, pelvis
- CT scans: head, abdomen
What is the secondary survey?
Head-to-toe physical exam
Complete history
Head Trauma injuries & risk
- Seizures common but self-limited
- Infants at risk for bleeding in subgaleal & epidural spaces
- Open fontanelles & cranial sutures
- But more tolerant of expansion
What are the 3 different types if intracranial bleeds in children?
- Epidural hematoma
- Subdural hematoma
- Intracerebral hematoma
Epidural hematoma
- definition
- clinical features
- diagnosis
- management
- prognosis
- Bleeding btwn the inner table of the skull/dura
- Tearing of the middle meningeal artery
- Signs & symptoms of intracranial pressure
- Head CT: lenticular density
- Immediate surgical drainage
- Good prognosis w/ surgery
Subdural hematoma
- definition
- clinical features
- diagnosis
- management
- prognosis
- Blood beneath the dura
-
Tearing of bridging meningeal veins
- Direct trauma or shaking
- More common than epidural
- Seizures, signs & symptoms of increased ICP
- Bilateral (75%), slow development
- Head CT: crescentic density
- Neurosurgical consult, surgical drainage
- Poor prognosis if underlying brain injured
Intracerebral hematoma
- definition
- management
- Bleeding w/i the brain parenchyma
- Frontal & temporal lobes
- Opposite side of impact injury
- Contrecoup injury
- Surgical drainage
First sign & symptom of increased ICP
-
First symptoms
- Headache
-
First signs
- Pupillary changes
- Altered mental status
What are the symptoms of increased ICP?
- Headache
- Vomiting
- Stiff neck
- Double vision
- Transient loss of vision
- Episodic severe headache
- Gait disturbance
- Dulled intelect
- Irritability
What are the signs of increased ICP?
- Papilledema
- Cranial nerve palsies
- Stiff neck
- Head tilt
- Retinal hemorrhage
- Macewen’s sign
- Hyperresonance of the skull on percussion
- Obtundation
- Unconsciousness
- Progressive hemiparesis
Increased ICP may lead to ________.
- Cerebral herniation
- Transtentorial or uncal
What are the 5 clinical features of herniation?
-
Bradycardia
- Early sign in children <4 YO
- Fixed & dilated ipsilateral pupil
- Contralateral hemiparesis
-
Pupils eventually bilaterally fixed & dilated
- Bilateral hemiparesis
-
Cushing’s triad (late sign)
- Bradycardia + HTN + irregular breathing
How is increased ICP managed?
-
Mild hyperventilation
- 100% to lower PaCO2 to 30-35 mmHg
- Vasoconstricts cerebral vessels
-
Elevation of head to 30-45o
- Venous drainage
-
Diuretics
- Mannitol
- Neurosurgical consultation
Spinal cord injury in children
-
SCIWORA
- Spinal cord injury w/o radiographic abnormality
- More common in children than adults
Chest trauma
- Children vs. adults
- Complications
- Child’s soft & pliable chest wall allows transmission of forces into lung parenchyma
-
Tension pneumothorax
- Life-threatening
- Distended neck veins, decreased breath sounds, hyperresonance to percussion, displaced trachea, pulseless electrical activity, shock
- Emergent chest decompression by needle thoracotomy
- Waiting for radiograph leads to death
Common sources of abdominal trauma in children
-
Duodenal hematoma
- RUQ injury (bicycle handle bar)
- Abd pain & vomiting
- Bowel obstruction
-
Lap belt injuries
- MVA, liver/spleen lacerations, bowel perf
- Chance fracture: flexion disruption of the lumbar spine
-
Spleen, liver, kidney injury
- Blunt trauma
_____ are the second most common cause of accidental death in children.
Burns
- Scalding injuries from hot liquids most common
- Always consider child abuse
What is a first degree burn?
- Epidermis
- Red, blanching, painful skin
- Heals w/o scarring
- Example: sunburn
What is a second degree burn?
- Entire epidermis & part of the dermis
-
Superficial partial thickness burns
- Entire epidermis & outer dermis
- Moist, painful, red
- Blister but don’t scar
-
Deep partial thickness burns
- Entire epidermis & lower dermis
- Pale white
- Blister & heal w/ scarring
What is a third degree burn?
- Full thickness burn
- Epidermis, dermis, subq tissue
- Dry, white, leathery
- Skin grafts needed
- Nerve endings burned (insensitivity to pain)
How do you calculate body surface area burned?
- Lund-Browder classification
- Adolescents & adults
- each arm 9%
- each leg 18%
- anterior trunk 18%
- posterior trunk 18%
- head & neck 9%
- Children: palm 1%
What is the initial resuscitation after a burn injury?
-
Endotracheal intubation
- Inhalation of hot gas
- Burn upper airway, edema, obstruction
-
Assess oxygenation
- pulse ox, administer 100% O2
- assess for CO inhalation
-
IV access
- nonburned skin
_____ resuscitation after a burn injury is critical because _____.
Fluid
- Large volumes of fluid may be lost from burned skin & leaky capillaries
What is the treatment for….
- first degree burns
- second degree burns
- third degree burns
-
first degree burns
- moisturizers, analgesics
-
second degree burns
- analgesics (opiates)
- debridement of skin to prevent infection
- bullae (large blisters) left alone unless already ruptured
- abx (topical 1% silver sulfadiazine)
-
third degree burns
- skin grafting, hydrotherapy
- escharotomy if restricts blood flow or chest expansion
- abx (topical 1% silver sulfadiazine)
With a burn injury, when is hospitalization required?
- Partial thickness burns >10% BSA
- Full thickness burns >2% BSA
- Burns specific to areas of the body
- Face, perineum, hands, feet, burns overlying a joint, circumferential burns
- Suspected inhalation injury
- Suspected nonaccidental trauama (inflicted burn)
What is the definition of a near-drowning?
Victim who survives, sometimes only temporarily, after asphyxia while submerged in a liquid
Submersion-related injuries are the ___ leading cause of death in the US.
The age distribution in childhood is _____.
- 5th leading cause, bimodal age distribution
-
Older infants & toddlers
- Wander into unfenced pools or tip into water containers
-
Adolescents
- M > F, submersion injury
- Alcohol/drug ingestion
What is the pathophysiology of a near-drowning?
-
Asphyxia
- aspirating liquid (wet drowner)
- laryngospasm (dry drowner)
- Fresh & salt water drowning
- Denaturing of surfactant
- Alveolar instability & collapse
- Pulmonary edema
-
End result
- Decreased pulmonary compliance
- Increased airway resistance
- Increased pulmonary artery pressures
- Impaired gas exchange
What are the clinical features of a near-drowning?
-
Respirations absent/irregular
- Coughing up pink/frothy material
- Rales, rhonchi, wheezes
- Pneumonia from fluid aspiration (>24 hrs)
- Hypoxemia & hypercarbia (first 12-24 hrs)
-
Neurologic insult (hypoxic CNS injury)
- Length & severity of hypoxia
- Alert vs. agitated, combative, comatose
- CV (dysrhythmias, myocardial ischemia)
- Heme (hemolysis, DIC)
- Renal failure
What is the management of a near-drowning?
- Treatment same whether fresh or salt water
-
Initial resuscitation
- ABCs, cervical spine immobilization, removal of wet clothing
-
Intubation & mechanical ventilation
- High PEEP for respiratory failure
-
Rewarming of body temperature
- Warm saline gastric lavage, bladder washings, peritoneal lavage
- Severe hypothermia: until 32oC (89.6oF)
- Attention to fluids/electrolytes
Prognosis after a near-drowning is poor for….
- Children <3 YO
- Submersion time >5 min
- Resuscitation delay >10 min
- Cardiopulmonary resuscitation required
- Abnormal neuro exam or seizures
- Arterial blood pH <7
What is the protocol for reporting child abuse?
What does child abuse include?
- Health-care personnel have a legal obligation to report suspected child abuse or neglect
- Index of suspicion of abuse should be high
- Child abuse includes:
- Physical abuse
- Psychological abuse
- Neglect
- Sexual assault
Which children are at high risk for abuse?
- Any child is at risk for abuse
-
Greatest risk:
- Age <4 YO (especially <1 YO)
- Mental retardation, developmental delay, severe handicap, hyperactivity, challenging temperament (colic, tantrums)
- Hx premature birth, low birth weight, neonatal separation from parents, multiple births
What are the risk factors for an abusive caregiver?
- Low self-esteem, social isolation, depression, hx of substance abuse
- Hx of abuse as a child
- Hx of mental illness
- Hx of violent temperament
- Family dynamics that include single parenthood, unemployment, poverty, marital conflicts, domestic violence, poor parent-child relationships, unrealistic expectations of the child
What are the 6 clinical features of child abuse?
- Bruises
- Human bites
- Burns
- Fractures
- Head injuries
- Visceral injuries
Age of bruise based on color pattern
- Red-blue
- Blue-purple
- Green
- Yellow-brown
- Red-blue: 0-3 days
- Blue-purple: 3-5 days
- Green: 5-8 days
- Yellow-brown: 8-14 days
What types of bruises are indicative of child abuse?
- Fleshy or protected areas
- Inflicted injury: face, neck, back, chest, abdomen, buttocks, genitalia
- Noninflicted injury: shins, knees, elbows, forehead (exposed areas)
- Aged on basis of color
- Patterns of bruising determine object
- Belt loops, buckles, hangers, hands
What types of burns are indicative of child abuse?
-
Accidental burns
- Irregular, spashlike
-
Non-accidental burns
- Clear line of demarcation
- “stocking” or “glovelike” = submersion
- Objects used to burn may be branded
- Irons, cigarettes
What types of fractures are indicative of child abuse?
- Inconsistent w/ hx or child’s developmental ability
-
Metaphyseal fractures
- “bucket handle” or corner fractures
- Torsional force on the limb (pulling & twisting) or violent shaking
- Fractures of the posterior or 1st ribs, sternum, scapula, vertebral spinous process
- Multiple fractures in different stages of healing
What types of head injuries are indicative of child abuse?
- Trauma, asphyxiation, shaking
- Leading cause of death & morbidity from child abuse
-
Shaken baby syndrome
- Child <2 YO
- Violently shaken
- Retinal hemorrhages
- Subdural hematomas
- Metaphyseal fractures
- Significant brain injury
What types of visceral injury are indicative of child abuse?
- Second leading cause of death from child abuse
- Rupture & injury of the intestinal tract, liver, spleen
How is child abuse diagnosed?
-
History is critical
- Child development should correlated w/ nature of the injury
- Delay in medical attention, implausable hx, inconsistency are suspicious
- Physical exam
- Acute injuries, old lesions
- Dilated ophthalmoscopic evaluation for retinal hemorrhages
- Accessory tests
- Skeletal survey (old/healing fractures)
- Head or abd CT scans (acute injuries)
How is child abuse managed?
- Child protective services or law enforcement agencies must be notified if there is a suspicion of abuse
- Hospitalization may be required or until a safe location for the child is identified
Are there physical signs of sexual abuse?
Who are the perpetrators?
Males vs. females?
- Unlike physical abuse, there are typically no overt physical signs of trauma
- Perpetrators are often known to the child
- 80% occurs in females
How do you use history to diagnose sexual abuse?
- Hx of abuse from a young child is difficult
- Open-ended questions
- Interviewer trained in sexual abuse eval
- Sexually abused children present w/ multiple non-specific complaints (abd & GU symptoms)
- Sexual behavior in young children raises red flags for abuse
How do you use physical exam to diagnose sexual abuse?
- Signs of trauma should be noted
- Genital & perianal examination
- Females: hymen, vagina, perianal areas
- Males: penis, scrotum, perianal area
- Note discharge, injury, bleeding
- Physical exam is normal in most victims
What are some labs for evaluation of sexual abuse?
- Labs to collect forensic evidence if abuse occurred w/i 72 hrs of presentation
- Cultures or serologic testing for STIs (& HIV)
- Test for pregnancy
- Assess vaginal fluid for spermatozoa
How do you manage sexual abuse?
- Safety of the child should be the highest priority
- Child protective services or social services must be notified & should arrage f/u & support
- Pregnancy may be prevented w/ high-dose oral contraceptives (morning-after pills)
- Antibiotics should be prescribed to empirically treat STDs
What is Sudden Infant Death Syndrome (SIDS)?
- Death of an infant younger than 1 YO
- Death remains unexplained after a thorough case investigation
- Autopsy
- Death scene evaluation
- Review of clinical hx
What is the epidemiology of SIDS?
- Most common cause of death in children <1 YO
- 2 in 1,000 live births
- Peak incidence at 2-4 mo
- Typical victim found dead in the morning after being put to sleep at night
How is SIDS managed?
-
Resuscitation
- Difficult to ascertain period of time infant has been apneic & pulseless
- If unsuccessful, autopsy
-
Postmortem exam
- Intrathoracic petechaie (80%)
- Pulmonary congestion or edema
- Small airway inflammation
- Evidence of hypoxia
What is the epidemiology of child poisonings?
- 60% in children <6 YO
- 90% accidental
- Majority at home when caregiver distracted
- Most ingested
- Some inhaled, spilled on skin or eyes, injected
- Mortality <1%
What are the 9 most common toxic exposures for children?
- Cosmetics & personal-care products
- Most common toxic exposure
- Cleaning agents
- Cough & cold preparations
- Vitamins, including iron
- Anagesics (acetaminophen, NSAIDs, aspirin)
- Plants (6-7%)
- Alcohols (ethanol) & hydrocarbons (gasoline, paint thinner, furniture polish)
- Carbon monoxide
- Prescription medications
Consider poisoning in patients presenting with_____.
Nonspecific signs & symptoms
- Seizures
- Severe vomiting & diarrhea
- Dysrhythmias
- Altered mental status or abnormal behavior
- Shock
- Trauma
- Unexplained metabolic acidosis
How do you use history to diagnose poisoning?
-
Information about the toxin
- Name, concentration, route
- Potential poison dose calculated for worst-case scenario
- Amount ingested per kg of body weight
- Consider multiple agents in adolescents
-
Information about the environment
- Location, meds, plants, vitamins, herbs, chemicals, timing
Poisoning physical exam: odors
- Bitter almond
- Garlic
- Acetone
- Wintergreen
- Moth balls
- Bitter almond: cyanide
- Garlic: arsenic, organophosphates
- Acetone: salicylates, isopropyl alcohol
- Wintergreen: methyl salicylate
- Moth balls: camphor
Poisoning physical exam: skin
- Cherry red color
- Sweaty
- Dry skin
- Urticaria
- Gray cyanosis
- Cherry red color: CO, cyanide
- Sweaty: organophosphates, sympathomimetics
- Dry skin: anticholinergics
- Urticaria: allergic rxn
- Gray cyanosis: methemoglobinemia
Poisoning physical exam: eyes
- Miosis
- Mydriasis
- Nystagmus
- Retinal hemorrhages
- Miosis: opiates, phencyclidine, organophosphates, phenothiazines
- Mydriasis: amphetamines, cocaine, tricyclic antidepressants, atropine
- Nystagmus: dilantin, phencyclidine
- Retinal hemorrhages: CO, methanol
Poisoning physical exam: fever
- Cocaine
- TCAs
- Phencyclidine
- Salicylates
- Thyroxine
- Anticholinergics
- Amphetamines
- Theophylline
What are some lab studies to do after poisoning?
- Screening lab tests
- Serum glucose, serum & urine toxicology screens, electrolytes
- Anion gap should be calculated
- Na+ - (Cl- + HCO3-)
-
Increased anion gap (>16): AMUDPILES
- Alcohol
- Methanol
- Uremia
- DKA
- Paraldehyde
- Iron/isoniazid
- Lactic acidosis
- Ethylene glycol
- Salicylates
What imaging should be done after poisoning?
- Radiographic imaging of the abdomen
-
Radiopaque substances (CHIPE)
- Chloral hydrate & calcium
- Heavy metals
- Iodine & iron
- Phenothiazines
- Enteric-coated tablets
What should be managed initially after poisoning?
- ABCs
- Altered mental status
- Dextrose for hypoglycemia
- Naloxone for opiate overdose
- Poison control center consult for assitance
What are the steps of gastric decontamination?
- Syrup of ipecac
- Gastric lavage
- Activated charcoal
- Whole-bowel irrigation
- Antidotes
How is syrup of ipecac used for gastric decontamination?
-
Induces emesis
- direct gastric irritation
- CNS chemoreceptor stimulation
- Only effective w/i first 30 min after ingestion
- Contraindicated in victims w/ decreased level of consciousness, caustic or hydrocarbon ingestions & children <6 mo
- Doesn’t improve clinical outcome
- Use out of favor
How is gastric lavage used for gastric decontamination?
- Large bore orogastric tube
- Indications
- Life-threatening ingestions
- w/i 1 hr after ingestion
- Toxins that delay gastric emptying (salicylates)
- Contraindications
- Caustic
- Hydrocarbon
- Non-toxic ingestions
- Delayed presentation
- Lack of evidence of clinical improvement
How is activated charcoal used for gastric decontamination?
- Very large absorptive surface area
- Binds toxins & minimizes absorption
- Should be considered for all poisonings
- Disadvantages
- Ineffective for: iron, lithium, alcohols, ethylene glycol, iodine, potassium, arsenic
- Interferes w/ visualization during endoscopy
- Don’t use for caustic ingestions
- Improves clinical outcome (esp w/i 1 hr)
How is whole-bowel irrigation used for gastric decontamination?
- Rapid, complete emptying of the intestinal tract w/ polytheylene glycol (osmotic agent) + electrolyte solution (prevents electrolyte imbalance)
- Helpful for ingestion of iron, heavy metals, sustained release medications
What is the pathophysiology of acetaminophen poisoning?
-
Hepatic damage
- Major sequelae of toxicity
- Depletion of glutathione (cofactor for metabolism by CYP450 system)
-
Toxic intermediates
- Produced when glutathione depeleted
- Bind to hepatocytes
- Hepatocellular necrosis
Stages of Acetaminophen Toxicity (timing)
- Stage 1
- Stage 2
- Stage 3
- Stage 4
-
Stage 1
- 30 min - 2 hrs
-
Stage 2
- 24-72 hrs
-
Stage 3
- 72-96 hrs
-
Stage 4
- 4 days - 2 wks
What are the signs/symptoms of stage 1 of acetaminophen toxicity?
- Asymptomatic
- Vomiting & diarrhea
What are the signs/symptoms of stage 2 of acetaminophen toxicity?
- GI symptoms resolve
- 36 hrs: hepatic transaminases begin to increase
What are the signs/symptoms of stage 3 of acetaminophen toxicity?
- Hepatic necrosis
- Jaundice
- Hypoglycemia
- Lactic acidosis
- Hepatic encephalopathy
- Coagulopathy
- Renal failure
What are the signs/symptoms of stage 4 of acetaminophen toxicity?
- Resolution of symptoms
- Progressive liver damage requiring liver transplantation
- Death
How is acetaminophen toxicity managed?
- Gastric lavage (life-threatening ingestion)
- Activated charcoal
- Obtain serum acetaminophen level 2-4 hrs after
- Matthew-Rumack nomogram
- Determines hepatitis potential
-
Hepatitis –> antidote is N-acetylcysteine
- Glutathione precursor
- Oral 140 mg/kg loading dose
- 70 mg/kg every 4 hrs for 17 doses
- Hepatoprotective w/i 8 hrs of ingestion
- Helpful up to 72 hrs post ingestion
What are some examples of salicylates?
What is the pathophysiology of salicylate poisoning?
- Pepto-Bismol, Ben-Gay, oil of wintergreen
-
Salicylates directly stimulate respiratory centers
- Hyperventilation
- Overcompensation of metabolic acidosis
- Respiratory alkalosis
-
Salicylates uncouple oxidative phosphorylation
- Lactic acidosis, enhances ketosis
What are the clinical features of salicylate poisoning?
- Fever, diaphoresis, flushed appearance
- Tinnitus
- Vomiting
- Headache
- Lethargy, restlessness, coma, seizures
- Hyperpnea
- Dehydration
What are the laboratory features of salicylate poisoning?
- Respiratory alkalosis + anion gap metabolic acidosis
- Hyperglycemia followed by hypoglycemia
- Hypokalemia
How is salicylate poisoning managed?
- Gastric lavage
- Activate charcoal every 4 hrs
- Obtain serum salicylate level at least 6 hrs after
- Done nomogram to assess toxicity
- Alkalinization of urine w/ NaHCO3 (urine pH >7) & large volume IVF enhance renal excretion
- Dialysis (life-threatening)
_____ is one of the most common & potentially fatal childhood poisonings. As little as ____ is toxic.
Iron
20 mg/kg
What are the most common sources of accidental iron ingestion?
- Adult-strength ferrous sulfate tablets
- Iron in prenatal vitamins
What is the pathophysiology of iron poisoning?
- Direct damage to the GI tract (hemorrhage)
- Hepatic injury & necrosis
- Third spacing & pooling of fluid in the vasculature (hypotension)
- Interference w/ oxidative phosphorylation
Iron Toxicity
- Stage 1
- Stage 2
- Stage 3
- Stage 4
-
Stage 1 (1-6 hrs)
- Abd pain, vomiting, diarrhea, GI bleeding
- Shock from bleeding & vasodilation
- Fever & leukocytosis
-
Stage 2 (6-12 hrs)
- Resolution of stage 1 symptoms
-
Stage 3 (12-36 hrs)
- Metabolic acidosis
- Circulatory collapse
- Hepatic & renal failure
- DIC
- Neurologic deterioration
-
Stage 4 (2-6 wks)
- Late sequelae: pyloric or intestinal scarring w/ stenosis
How should iron poisoning be managed?
- Gastric lavage
- Activated charcoal does NOT bind to iron
- Hypovolemia, blood loss, shock treatment
- WBI considered for life-threatening indigestion
- Serum iron level 2-6 hrs post-ingestion
-
IV deferoxamine (iron-binding ligand)
- Serum iron >500 ug/dL [OR]
- >300 ug/dL & acidosis, hyperglycemia, leukocytosis present
- Severe GI symptoms
- >100 mg/kg iron ingested
-
Test dose of deferoxamine
- Urine red/pink (vin rose) = +++ challenge
- Clinically significant iron ingestion
What are some sources of lead?
- Lead based paint chips
- Water carried by outdated lead pipes
- Improperly glazed or foreign-made ceramic food or water containers
- Pica: compulsive eating of non-nutrient substances such as dirt, paint, clay
What are the 4 clinical features of lead poisoning?
(can be chronic ingestion or acute)
-
Abdominal complaints
- Colicky pain, constipation, anorexia, vomiting
-
CNS complaints
- Listlessness, irritability, seizures, decreased consciousness w/ encephalopathy
-
Peripheral blood smear
- Microcytic anemia, basophilic stippling, RBC precursors
- Abd radiographs: radioopacities
- Radiographs of knees/wrists
- Dense metaphyseal bands (lead lines)
Lead poisoning
diagnosis
management
- Elevated lead level
- Elevated erythrocyte protoporphyrin
- Treatment
- Dimercaprol
- British anti-lewisite (BAL)
- EDTA
What are caustic agents?
acids or alkalis w/ corrosive potential
What kind of injury does acid poisoning cause?
- ex: toilet bowl cleaner
- Coagulation necrosis
- Superficial damage to the mouth, esophagus, stomach
- More severe damage if pH < 2
What kind of injury does alkalis poisoning cause?
- ex: oven & drain cleaners, bleach, laundry detergent
- Liquefaction necrosis
- Deep & penetrating damage to the mouth & esophagus
- More severe if pH > 12
What are the 4 clinical features of poisoning w/ caustic agents?
- Immediate burning sensation
- Intense dysphagia, salivation, restrosternal chest pain, vomiting
- Obstructive airway edema (acid > alkalis)
- Gastric perforation & peritonitis (acid)
- Esophageal perforation w/ mediastinitis (alkali)
How should poisoning w/ caustic agents be managed?
- No attempt should be made to neutralize
- Combination of acid + alkali will generate an exothermic rxn & worsen any burn
- Ipecac, gastric lavage, activated charcoal are all CONTRAINDICATED
- Charcoal interferes w/ endoscopy
- Endoscopy to assess damage
- Household bleach has less corrosive potential
- No treatment
How are people exposed to excessive CO?
- Byproduct of incomplete combustion of carbon-containing material
- Fires, tobacco, faulty home heaters, car exhaust, industrial pollution
- CO is odorless, tasteless, colorless
What is the pathophysiology of CO poisoning?
- CO interferes w/ O2 delivery & utilization
-
CO displaces O2 from the Hgb molecule
- Forms CO-Hgb, can’t carry O2
- Bond 200X stronger w/ CO than O2
-
O2-Hgb dissociation curve shifted to the left
- Tighter binding of remaining O2
- Impaired release of O2 to tissues
- CO interferes w/ cellular oxidative metabolism
Clinical features of CO poisoning
- Low levels
- High levels
- Low levels
- Nonspecific symptoms
- HA, flulike illness, dyspnea w/ exertion, dizziness
- High levels
- Visual & auditory changes, vomiting, confusion, syncope, slurred speech, cyanosis, myocardial ischemia, coma, death
What are the clinical findings of CO poisoning?
- classic
- young children
- neuro
- Cherry red skin
- Retinal hemorrhages
- Tachycardia, tachypnea
-
Young children (<8 YO)
- More symptoms at lower CO-Hb levels
- GI symptoms (vomiting, diarrhea)
-
Delayed permanent neuropsychiatric syndrome
- Memory loss, personality changes, deafness, seizures
- Up to 4 wks after exposure
How is CO poisoning diagnosed?
-
Measuring CO-Hb level
- Not always indicative of CO exposure
- May be low in victims w/ significant intoxication
- Anion-gap metabolic acidosis
- Low O2 saturation (PaO2 may be normal)
- Evidence of myocardial ischemia on ECG
- Elevated cardiac enzymes
How is CO poisoning managed?
-
100% O2
- Displace CO from Hgb
-
Hyperbaric O2
- More rapidly displaces CO from Hgb
- Improves O2 delivery to tissues
-
Hospitalization
- CO-Hb >25%
- CO-Hb >10% during pregnancy, hx or presence of neuro symptoms, metabolic acidosis or ECG changes
What is the epidemiology of mammalian bites?
- Dogs (80%)
- Cats, rodents, other wild/domestic animals
- Humans (2-3%)
- Boys during spring/summer months
What are the clinical features of dog bites?
-
Bites range in severity
- Scratches, punctures, lacerations, severe tissue injury
- Jaw pressure >200-450 lb/in2
- Young children bitten on head & neck
- Older children bitten on extremities
-
Secondary infections
- Anaerobic & aerobic organisms
- Staph aureus, Pasteurella multocida, Strep
How are dog bites managed?
- Copious wound irrigation
- Wounds on the face, large wounds, wounds <12 hrs old should be sutured
- Facial wounds <24 hrs old can be sutured
- Face has increased vascularity
- Wounds at high risk for infection
- Hand, wrist, foot, small puncture wounds
- Antibiotics: amoxicillin-clavulanic acid
- Tetanus prophylaxis
What are the clinical features of cat bites?
What is the treatment?
- Puncture wounds to the UE most common
- Victims have higher risk of infection
- Pasteurella multocida
- Cat scratch disease (regional lymphadenitis)
- Treatment
- Similar to dog bites
- Adequate irrigation difficult
What are the common types of wounds w/ human bites?
- Trunk or face in young children
- Fist fight: metacarpophalangeal joint
- Wounds extremely serious
- Infection may penetrate the avascular fascial layers –> deep infection & tendonitis
What types of infections in human bites?
- Infection rate is high
- Mixed bacterial infection
- Streptococcus viridans, Staph aureus
- Bacteroides, Peptostreptococcus, Eikenella corrodens
- Other systemic infections
- Hepatitis B, HIV, syphilis
How are human bites managed?
- Copious wound irrigation
- Closure of large lacerations
- Antibiotics: amoxicillin-clavulanic acid
What are the types of poisonous spiders?
- Black Widow Spider (Lactrodectus species)
- Brown Recluse Spider (Loxosceles species)
The black widow spider is characterized by….
- Red/orange hourglass marking on ventral surface
- Only the female spider is dangerous
- Bites only if provoked
- Web located in dark recesses
- Closets, woodpiles, attics
What are the clinical features of a Black Widow Spider bite?
- Venom is a potent neurotoxin
- Few local symptoms (burning, sharp pinprick)
- Pathognomonic signs/symptoms
- Severe HTN, muscle cramps
- Nonspecific symptoms
- HA, dizziness, nausea, vomiting, anxiety, sweating
What is the management of a Black Widow Spider bite?
-
Local wound care
- Wound irrigation, tetanus prophylaxis
-
Benzodiazepines & narcotics
- Muscle cramps
-
Lactrodectus antivenin
- Signs/symptoms of severe envenomation
The Brown Recluse Spider is characterized by…
- “Fiddle-back spider”
- Brown violin-shaped marking on dorsum of thorax
- Bites only if provoked
- Web located in dark recesses
What are the clinical features of a brown recluse spider bite?
- Venom: cytotoxic compound containing tissue-destructive enzymes
- Bite
- Little initial pain
- 1-8 hrs: painfully itchy papule
- 3-4 days: increases in size, discolors
- Necrotic & ulcerated deep lesion
-
Systemic rxns (24-48 hrs)
- Fever, chills, weakness, vomiting, joint pain, DIC, hemolysis, renal failure from myoglobinuria
How is a brown recluse spider bite treated?
- Local wound care
- Tetanus prophylaxis
- Treatment of necrotic ulcer
- Steroids, skin grafting, dapsone, hyperbaric oxygen
- No antivenin
What are the characteristics & pathophysiology of
pit viper snake bites?
- Family Crotalidae, >95% snake bites
- Rattlesnake, cottonmouth, copperhead snakes
- Bite location & amt of venom injected determine the severity of envenomation
- Head & trunk bites most severe
- Venom: complex mixture of proteolytic enzymes
What are the clinical features of a pit viper snake bite?
- Local findings
- Puncture marks, progressive severe swelling, ecchymosis
- Systemic effects
- Paresthesias of the scalp
- Periorbital fasciculations
- Weakness, diaphoresis, dizziness, nausea
- Metallic taste in the mouth
- Coagulopathy, thrombocytopenia, hypotension, shock
How are pit viper snake bites treated?
- Local wound care, tetanus prophylaxis, immobilization, immediate transport to ER
- Incision & suction NOT recommended
- More injury: tourniquets, ice, direct pressure
-
Crotalidae polyvalent antivenin (all bites)
- Children: more antivenin
- Most effective w/i 4-6 hrs
- Complications: serum sickness, anaphylaxis
-
Crotalidae polyvalent immune Fab
- Safe, more potent, very effective
Coral snake bites
- characteristics
- clinical features
- management
- Family Elapidae, 1-2% all snakebites
- “red next to yellow, kill a fellow”
- “red next to black, venom lack”
- Clinical (neurotoxic venom)
- Local swelling & tenderness
-
Severe systemic symptoms
- Paresthesias, vomiting, weakness, diplopia, fasciculations, confusion, respiratory depression
- Treatment
- Antivenin, local wound care, supportive