Emergency Medicine Flashcards
(139 cards)
1
Q
What is the most common cause of cardiac arrest in a child? Uncommon cause? Survival?
A
-
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
2
Q
What are the essentials of CPR?
A
- Airway
- Breathing
- Circulation
3
Q
How do you expose an airway?
A
- First priority in resuscitation
- Most common obstruction: tongue
- Head-tilt method
- Jaw-thrust method
- Neck or cervical spine injury
4
Q
How do you evalulate breathing?
A
-
Look. Listen. Feel.
- Look for rise & fall in chest
- Listen for exhaled air
- Feel for exhaled airflow
- Rescue breathing if spontaneous absent
5
Q
How do you evaluate circulation?
A
- Need for chest compressions determined after 2 rescue breaths
- Pulse assessment
- Infants: brachial artery
- Children: carotid artery
- Chest compressions: asystole, bradycardia
6
Q
What is the definition of Shock?
A
- Inadequate delivery of O2 & metabolic substrates to meet the metabolic demands of tissues
- Normal or decreased BP
7
Q
What are the 3 degrees of Shock?
A
-
Compensated
- Normal BP & CO, adequate tissue perfusion
- Maldistributed blood flow
-
Decompensated
- Hypotension, low CO
- Inadequate tissue perfusion
-
Irreversible
- Cell death, refractory to medical treatment
8
Q
What are the 3 categories of Shock?
A
- Hypovolemic
- Septic
- Distributive
9
Q
What is hypovolemic shock?
A
- Most common cause of shock in children
- Decreased circulating blood volume
- Hemorrhage, dehydration
- Amt volume determines compensation
- Endogenous catecholamines
- Volume loss >25% = decompensated shock
10
Q
What is septic shock?
A
- 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
11
Q
What is distributive shock?
A
-
Distal pooling of blood or fluid extravasation
- Anaphylactic or neurogenic shock
- Medications/toxins
- Types
- Anaphylactic shock
- Neurogenic shock
- Cardiogenic shock
12
Q
What is anaphylactic shock?
A
Extravasation of intracellular fluid from permeable capillaries
- Acute angioedema of the upper airway
- Bronchospasm
- Pulmonary edema
- Urticaria
- Hypotension
13
Q
What is neurogenic shock?
A
- 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
14
Q
What is cardiogenic shock?
A
- 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
15
Q
Recognition of shock may be difficult because…..
A
- Presence of compensatory mechanisms
- Prevent hypotension until 25% of intravascular volume lost
- Index of suspicion for shock must be high
16
Q
What are 6 historical features that may suggest the presence of shock?
A
- Severe vomiting & diarrhea
- Trauma w/ hemorrhage
- Febrile illness (esp immunocompromised pt)
- Symptoms of CHF
- Exposure to known allergic antigen
- Spinal cord injury
17
Q
Physical exam of a patient in shock?
A
- 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
18
Q
Important laboratory studies for shock?
A
- CBC - blood loss & infection
- Electrolytes - metabolic acidosis, electrolyte ab
- BUN & creatinine - renal function/perfusion
- Ca & Glu - metabolic derangements
- Coagulation factors - DIC
- Toxicology screens - poisoning
19
Q
How is shock managed?
Resuscitation? Medications?
A
- 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
20
Q
Trauma is the leading cause of death in children older than _____ year of age.
______ are the leading cause of trauma.
A
1 year of age
Motor vehicle accidents
21
Q
How is a child’s response to trauma unique?
A
- 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
22
Q
What is the primary survey in trauma?
A
- 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
23
Q
Glascow Coma Scale in Verbal Patient
- Eye opening
- Best motor response
- Best verbal response
A
-
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)
24
Q
Glascow Coma Scale in Nonverbal Patient (Child)
- Eye opening
- Best motor response
- Best verbal response
A
-
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)
25
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
26
What is the secondary survey?
Head-to-toe physical exam
Complete history
27
**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
28
What are the 3 different types if intracranial bleeds in children?
* Epidural hematoma
* Subdural hematoma
* Intracerebral hematoma
29
**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
30
**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
31
**Intracerebral hematoma**
* definition
* management
* Bleeding w/i the brain parenchyma
* Frontal & temporal lobes
* Opposite side of impact injury
* **Contrecoup injury**
* Surgical drainage
32
First sign & symptom of increased ICP
* **First symptoms**
* Headache
* **First signs**
* Pupillary changes
* Altered mental status
33
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
34
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
35
Increased ICP may lead to \_\_\_\_\_\_\_\_.
* Cerebral herniation
* Transtentorial or uncal
36
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
37
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**
38
Spinal cord injury in children
* **SCIWORA**
* Spinal cord injury w/o radiographic abnormality
* More common in children than adults
39
**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
40
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
41
\_\_\_\_\_ are the second most common cause of accidental death in children.
**Burns**
* _Scalding_ injuries from hot liquids most common
* Always consider child _abuse_
42
What is a **first** degree burn?
* Epidermis
* Red, blanching, painful skin
* Heals w/o scarring
* Example: sunburn
43
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
44
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)
45
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%
46
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
47
\_\_\_\_\_ resuscitation after a burn injury is critical because \_\_\_\_\_.
**Fluid**
* Large volumes of fluid may be lost from burned skin & leaky capillaries
48
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)
49
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)
50
What is the definition of a **near-drowning**?
Victim who survives, sometimes only temporarily, after asphyxia while submerged in a liquid
51
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
52
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
53
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**
54
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**
55
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
56
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**
57
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
58
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
59
What are the 6 clinical features of child abuse?
* Bruises
* Human bites
* Burns
* Fractures
* Head injuries
* Visceral injuries
60
**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
61
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
62
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
63
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**
64
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
65
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
66
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)
67
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
68
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_
69
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**
70
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**
71
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
72
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
73
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
74
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
75
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
76
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%
77
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
78
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
79
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
80
**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
81
**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
82
**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
83
**Poisoning physical exam: fever**
* Cocaine
* TCAs
* Phencyclidine
* Salicylates
* Thyroxine
* Anticholinergics
* Amphetamines
* Theophylline
84
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
85
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
86
What should be managed **initially** after poisoning?
* ABCs
* Altered mental status
* Dextrose for hypoglycemia
* Naloxone for opiate overdose
* Poison control center consult for assitance
87
What are the steps of gastric decontamination?
* Syrup of ipecac
* Gastric lavage
* Activated charcoal
* Whole-bowel irrigation
* Antidotes
88
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
89
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
90
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)**
91
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
92
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
93
**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
94
What are the signs/symptoms of **stage 1** of acetaminophen toxicity?
* Asymptomatic
* Vomiting & diarrhea
95
What are the signs/symptoms of **stage 2** of acetaminophen toxicity?
* GI symptoms resolve
* 36 hrs: hepatic transaminases begin to increase
96
What are the signs/symptoms of **stage 3** of acetaminophen toxicity?
* Hepatic necrosis
* Jaundice
* Hypoglycemia
* Lactic acidosis
* Hepatic encephalopathy
* Coagulopathy
* Renal failure
97
What are the signs/symptoms of **stage 4** of acetaminophen toxicity?
* Resolution of symptoms
* Progressive liver damage requiring liver transplantation
* Death
98
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
99
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
100
What are the clinical features of salicylate poisoning?
* Fever, diaphoresis, flushed appearance
* Tinnitus
* Vomiting
* Headache
* Lethargy, restlessness, coma, seizures
* Hyperpnea
* Dehydration
101
What are the **laboratory** features of salicylate poisoning?
* Respiratory alkalosis + anion gap metabolic acidosis
* Hyperglycemia followed by hypoglycemia
* Hypokalemia
102
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)
103
\_\_\_\_\_ is one of the most common & potentially fatal childhood poisonings. As little as ____ is toxic.
**Iron**
20 mg/kg
104
What are the most common sources of **accidental iron ingestion**?
* Adult-strength ferrous sulfate tablets
* Iron in prenatal vitamins
105
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
106
**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
107
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
108
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
109
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)**
110
**Lead poisoning**
diagnosis
management
* Elevated lead level
* Elevated erythrocyte protoporphyrin
* Treatment
* Dimercaprol
* British anti-lewisite (BAL)
* EDTA
111
What are caustic agents?
acids or alkalis w/ corrosive potential
112
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
113
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
114
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)
115
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
116
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**
117
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**
118
**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
119
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
120
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
121
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
122
What is the **epidemiology** of mammalian bites?
* Dogs (80%)
* Cats, rodents, other wild/domestic animals
* Humans (2-3%)
* Boys during spring/summer months
123
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
124
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**
125
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
126
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
127
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
128
How are human bites managed?
* Copious wound irrigation
* Closure of large lacerations
* Antibiotics: amoxicillin-clavulanic acid
129
What are the types of poisonous spiders?
* Black Widow Spider (*Lactrodectus* species)
* Brown Recluse Spider (*Loxosceles* species)
130
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
131
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
132
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
133
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
134
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
135
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
136
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**
137
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**
138
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
139
**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
