Transcript Emergency Procedures - Dr. Brahmbhatt`s Class Handouts

ADVERSITY
“Life’s challenges are not supposed to
paralyze you, they are supposed to help you
discover who you are.”
- Bernice Johnson Reagon
Emergency Procedures
Normal PE
Area
Organs
Cranial ventral abdomen
Liver, stomach, pancreas
Cranial dorsal abdomen
Kidneys, stomach, pancreas
Mid-ventral abdomen
Spleen, small bowel
Mid-dorsal abdomen
Kidneys, ureters, retroperitoneal space
Caudal ventral abdomen
Bladder, uterus
Caudal dorsal abdomen
Colon, sub-lumbar lymph nodes,
prostate, uterus
Use belts and your hands
ABCD
• A = Establish airway
• B = Breathe for animal
• C = Maintain circulation with
thoracic compressions and IV
fluids
• D = Disability
Triage of Emergency Patients
• Initial exam (by RVT)
–
–
–
–
Wear gloves
Animal muzzled (use discretion)
Minimize movement of patient
Initial Assessment (30-60 sec; from rostral
direction)
• Mentation (level of consciousness)
–
–
–
–
A Alert
V Verbally responsive
P responsive to painful stimuli
U Unresponsive
» Extend head/neck to provide clear airway; check for patency
• Breathing/respiratory pattern (shallow, labored, rapid, obstructed)
• Abnormal body/limb posture (fracture, paralysis)
• Presence of blood or other material around patient
Mucous membrane
Color
Interpretation
Causes
PINK
Adequate circulation and
perfusion
Normal circulatory system
WHITE OR PALE PINK
Anemia, decreased peripheral
perfusion, vasoconstriction
Anemia ( blood loss, inc.
destruction, dec. production)
shock
BLUE OR GREY
Hypoxemia, anemia
Respiratory embarrassment,
blood loss
DARK RED, BRICK RED
Increased peripheral perfusion:
cyanide toxicity
Fever, sepsis, systemic
inflammatory response, smoke
inhalation/ cyanide toxicity
BROWN
Methemoglobenemia
Acetaminophen, ibuprofen
YELLOW (ICTERIC)
Hyperbilirubinemia
Hemolysis, hepatic/ biliary
disease
PATECHIA
Coagulation disorder
Thrombocytopenia, decreased
platelet function
Triage of Emergency Patients
– Initial Assessment (continued)
• Breathing/respiratory pattern
– Total/Partial blockage of airways (Requires immediate Rx)
» Exaggerated inspirations
» Nasal flare, open mouth, extended head/neck
» Cyanosis
– Breathing assessment
» Watch chest wall movement
» Auscult lungs bilaterally to r/o hemo- or pneumothorax
Breathing – Airway patent
• NO
• YES
– Clear airway: use suction
– Intubate
– Ventilate (don’t over
ventilate drive CO2
down)
• 10/12/min
• < 20 cm H2O
– Provide flow-by air
Triage of Emergency Patients
– Vital signs (taken after initial
assessment)
• HR, pulse rate (same as
HR?), strength
• RR
• mm color, CRT
• Temp
• BP
– High HR, high BP→
pain
– High HR, low BP →
hypovolemic shock
– Baseline data
• ECG
• Chem panel, CBC
Triage of Emergency Patients
• History (mnemonic)
– A Allergies
– M Medications
– P Past History
– L Lasts (meals, defecation, urination,
medication)
– E Events (What is the problem now?)
Triage of Emergency Patients
– Events
• How long since injury
• Cause of injury (HBC,
dog fight, gunshot)
• Evidence of loss of
consciousness
• Blood loss?
• Deterioration/improve
ment since accident
(good indicator of
Prognosis)
• Any other underlying
medical
conditions/medications
Triage of Emergency Patients
Treatment to restore life/health
– Analgesics for pain
• Once airway patency and heart
beat are established (these are critical for life)
– Control hemorrhage
• Pressure bandages (sterile gauze, laparotomy pads,
towels)
– If bleed thru, do not remove initial bandage, apply
another on top
– On distal extremity, BP cuff can be placed proximal
to wound (avoid tourniquet if possible)
Triage of Emergency Patients
• Control hemorrhage
• External counterpressure using body wrap of pelvic
limbs, pelvis, and abdomen
– Insert urinary catheter to monitor urine output
– Use towels, cotton rolls, duct tape, etc
– Monitor respirations (diaphragm/abdominal
breathing compromised)
– Leave on until hemodynamically stable (6-24 h)
– Monitor BP during removal
» If BP drops >5 mm Hg, stop removal; infuse
more fluids
» If BP continues to drop, reapply wrap
Triage of Emergency Patients
SHOCK:
RECOGNITION AND TREATMENT
• SHOCK is inadequate tissue perfusion resulting in
poor oxygen delivery
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–
–
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Cardiogenic
Distributive
Obstructive
Hypovolemic
Shock
• Types of Shock:
– Cardiogenic—results from heart failure
• ↓ blood pumped by heart
• HCM, DCM, valvular insufficiency/stenosis
– Distributive—blood flow maldistribution (Vasodilation)
• Sepsis, anaphylaxis →↓arteriole resistance →loss of fluid from
vessels to interstitial spaces →↓BP→ ↓ blood return to heart
– Obstructive—physical obstruction in circ system
• HW disease → heart pumping against the adult worm blockage
• Gastric torsion →↓blood return to heart
– Hypovolemic—decreased intravascular volume
• Most common in small animals
• Blood loss, dehydration from excessive vomiting/diarrhea,
effusion of fluid into 3rd spaces
Hypovolemic Shock
•
Pathophysiology of hypovolemic shock
↓blood vol →↓venous return, ↓vent filling →↓stroke vol, ↓CO →↓BP
•
Stage I: Compensation
–
Baroreceptors detect hypotension (↓BP)
a.
Sympathetic reflex—(Epi, Norepi, cortisol released from adrenals)
-
b.
Renin (kidney)→angiotensin (blood)→aldosterone (adrenals) reflex
-
–
↑ HR, contractility
Constriction of arterioles (↑BP) to skin (cold, clammy), muscles, kidneys, GI
tract; not brain, heart
↑ Na+ and water retention → ↑ intravascular vol (↑BP)
PE findings
–
–
–
Tachycardia
Prolonged cap refill time
Pale mm
Hypovolemic Shock
• Pathophysiology of hypovolemic shock
• Stage II: Decompensation
– Tachycardia
– Delayed cap refill time
– Muddy mm (loss of pink color, more brown than pink)
– BP is dropping
– Altered mental state
• Stage III: Irreversible shock
– PE findings worsen
– cannot revive
– death will occur
Shock
• Treatment: the goal of therapy is to improve O2
delivery
– O2 supplementation (If pulse ox < = 93%)
• Face mask
• O2 cage/hoods
• Transtracheal/nasal insufflation
– Venous access
•
•
•
•
Cephalic
Saphenous
Jugular
Intraosseous
Oxygen supplementation
NASAL
CANNULA
FACE MASK
OXYGEN HOOD
Fluid Administration
Shock
• Treatment
– Fluid resuscitation (O2 delivery is improved by ↑CO)
1. Crystalloids
• Isotonic solutions (electrolytes: Na+, Cl-, K+, bicarbonate)
– Examples (body fluid=280-300 mOsm/L)
» Lactated Ringer’s (273 mOsm/L)
» Normal saline (0.9%) (308 mOsm/L)
– Dose: Dog 80-90 ml/kg/hr
Cat 50-55 ml/kg/hr
• Hypertonic solutions—when lg vol of fluid cannot be administered rapidly enough
– Examples—7.5% saline
– Causes fluid shift from intracellular space→ intravascular space →↑vascular vol
→↑venous return → ↑CO
– Also causes vasodilation → ↑ tissue perfusion
– Dose: 4-6 ml/kg over 5 min
• Hypotonic solutions should never be used for hypovolemic shock
– Examples—5% Dex in water (252 mOsm/L)
Shock
• Treatment
– Fluid resuscitation (O2 delivery is improved by ↑CO)
2. Colloids—
•
•
•
•
Large molecular wt solutions that do not leave vascular system
Better blood volume expanders than crystalloids
50-80% of infused volume stays in blood vessels
Examples
– Whole blood
– Plasma
– Dextran 70
Shock
• Rx (continued)
– Sympathomimetics
Use only after adequate fluid administration if BP and tissue perfusion
have not returned to normal
• Dopamine (Inotropin®)
– 0.5-3.0 μg/kg/min
» Dilation of renal, mesenteric, coronary vessels
– 3.0-7.5 μg/kg/min
» ↑ contractility of heart
» ↑ HR
– >7.5μg/kg/min
» Vasoconstriction
• Dobutamine (Dobutrex®)
– 5-15 μg/kg/min
– ↑ contractility of heart (min effect on HR)
Shock
• Monitoring
Hemodynamic/metabolic sequelae of shock are continually changing
– Physical Parameters
• Respiratory
–
–
–
–
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Color of mm
RR
Breathing efforts smooth?
Breathing pattern regular?
Auscultation normal?
• Cardiovascular
–
–
–
–
–
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HR normal?
ECG normal?
Color of mm
Cap refill time (1-2 sec)
Urine production? (1-2 ml/kg/hr)
Weak pulse? → ↓stroke volume
Shock
• Monitoring
– Physiologic Monitoring Parameters
• O2 Saturation
– Pulse oximetry—noninvasive
– Normal: Hb saturations (SpO2)>95%
» SpO2<90%--serious hypoxemia
• Arterial BP—a product of CO, vascular capacity, blood volume
– If one is subnormal, the other 2 try to compensate to maintain BP
Shock
• Monitoring
– Laboratory Parameters
• Hematocrit (PCV)
– Increase →dehydration
– Decrease →blood loss
• Electrolytes (what is that?)
– Proper balance needed for proper cell function
– Fluid therapy may alter the balance; supplement fluid as needed
• Arterial pH and blood gases
– PaCO2 tells how well patient is ventilating
» PaCO2 <35 mm Hg → hyperventilation
» PaCO2 >45 mm Hg → hypoventilation
– PaO2 Tells how well patient is being oxygenated
» PaO2 <90 mm Hg → hypoxemia
– pH tells acid/base status of patient
– <7.35 → acidosis
– >7.45 → alkalosis
VISION
“It is a terrible thing to see and
have no vision.”
-Helen Keller
CPCRCARDIOPULMONARY
CEREBROVASCULAR
RESUSCITATION
Cardiopulmonary Arrest and Resuscitation
(CPR)
Cardiopulmonary Arrest (CPA)— sudden cessation of effective ventilation and
circulation.
• Causes
•
•
•
•
•
•
Anesthesia
Trauma: head trauma
Infections (e.g. pneumonia)
Heart disease: arrhythmia
Autoimmune disease
Malignancy
Hypoxemia, shock, anemia
Cardiopulmonary Resuscitation
• Resuscitation Team Members
– Should be 3-5 members
• Team leader—Veterinarian or RVT with most experience
• All members have several responsibilities
–
–
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–
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Provide ventilation
Chest compression
Establish IV line
Administer drugs
Attach monitoring equipment
Record resuscitation efforts
Monitor team’s effectiveness
• Teams should practice on a regular basis to stay sharp
Cardiopulmonary Resuscitation
• Facilities
–
–
–
–
Adequate room for entire team and equipment
O2 source
Good lighting
Crash cart with all needed Rx
(should be checked at beginning of each shift)
• Defibrillators
• Electrocardiogram
• Suction
– Table to perform chest compression
• Grated surgery prep table not solid enough for chest compression
– Use board underneath patient
• Recognition
– RVT should ID patients at risk and observe any deterioration
– Preventing an arrest is easier than treating one
Agonal breaths, apnea, collapse, fixed gaze, no palpable pulase
Cardiopulmonary Resuscitation
• Standard Emergency Supplies (on crash cart)
– Pharmaceuticals
•
•
•
•
•
•
•
Atropine
Epinephrine
Vasopressin
2% lidocaine (w/o epi)
Na+ bicarb
Ca++ chloride or gluconate
Lactated Ringer’s, hypertonic saline,
dextran 70, hetastarch
– Airway access supplies
•
•
•
•
Laryngoscope
Endotracheal tubes (variety of sizes)
Lubricating jelly
Roll gauze
--Venous access supplies
●
●
●
Butterfly cath
● IV caths
● IV drip sets
● Bone marrow needles
● Syringes
Hypodermic needles (var sizes)
Adhesive tape
● Tourniquet
--Miscellaneous supplies
Gauze pads (3 x 3)
Stethoscope
● Minor surgery pack
● Suture material
● Scalpel blades
● Surgeon’s gloves
●
●
Emergency Drugs in Dogs
Emergency Drugs in Cats
CPR
• Basic Life Support:
– A -- Establishment of an Airway.
– B -- Breathing support.
– C -- Circulation support.
• Advanced Life Support:
– D -- Diagnosis and Drugs.
– E -- Electrocardiography.
– F -- Fibrillation control.
• Prolonged Life Support:
– G -- Gauging a patient's response.
– H -- Hopeful measures for the brain
– I -- Intensive care.
Cardiopulmonary Resuscitation
• Basic Life Support (Phase I)
– Remember the priorities (ABC; Airway, Breathing, Circulation)
• Establish patent Airway
– Endotracheal tube
– Tracheostomy tube for upper airway obstruction
– Suction to remove blood, mucus, pulmonary edema fluid, vomit
• Artificial ventilation (Breathing)
» Ambu-Bag
» Anesthetic machine
» Ventilate once every 3-5 sec (6-10 breaths/ min)
– Chest compressions in between breaths if working alone
» 1 to 2 times per second (80 times per minute for a large dog and 120
times for a small dog or cat)
» 10 compression for every 2 breaths (or 5:1)
CPR
• http://www.youtube.com/watch?v=VJGlsYHI9
cU
Cardiopulmonary Resuscitation
Intubation
Cardiopulmonary Resuscitation
• Basic Life Support (Phase I)
– Circulation
• External cardiac compression
– Lateral recumbency—one/both hands on thorax over heart (4th-5th intercostal
space)
– In larger patients, arms extended, elbows locked
– In small patients, thumb and first 2 fingers to compress chest
– Rate of compression: 80-120/min
Cardiopulmonary Resuscitation
• Basic Life Support (Phase I)
– Circulation
• Internal cardiac compression
– More effective than external compression
» ↑CO, ↑BP, higher survival rate
– Indications
» Rib fractures
» Pleural effusion
» Pneumothorax
» If not responsive after 5 min of external cardiac compression
– Preparation
» Clip hair ASAP, no surgical scrub
» Incision at 7th and 8th intercostal space
» With a gloved hand, compress heart between fingers and palm (Do
not puncture heart with finger tips or twist heart)
» After spontaneous beating returns, flush chest cavity with saline,
perform sterile scrub of skin and close
Cardiopulmonary Resuscitation
• Basic Life Support (Phase I)
– Assessing effectiveness (must be done frequently)
• Improved color of mm
• Palpable pulse during cardiopulmonary resuscitation (difficult)
• If efforts are not effective, do something differently
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Use different hand
Change person performing compression
Ventilate with every 2nd or 3rd chest compression
Compress chest where it is widest in lg breed dogs
Apply counter-pressure to abdomen (hand, sandbag)
» Prevents posterior displacement of diaphragm and increases
intrathoracic pressure
Cardiopulmonary Resuscitation
• Advanced Life Support (Phase II)
Add 2 priorities to ABC--D E (administer
Drugs, Electrical—defibrillate)
– Drugs
• Fluids
– Lactated Ringer’s is standard (do not use Dextrose)
» Initial dose:
Dogs—40 ml/kg
(rapidly IV)
Cats—20 ml/kg
• Atropine—parasympatholytic effects
(blocks parasympathetic effects)
– 0.02-0.04 mg/kg
– ↑HR
– ↓secretions
• Epinephrine—adrenergic effects
– 0.02-0.2 mg/kg
– Arterial and venous vasoconstriction→ ↑BP
Common arrhythmias: electrical mechanical dissociation, (no pulse), asystole
(flatline), ventricular tachcardia, bradycardia
Cardiopulmonary Resuscitation
• Advanced Life Support (Phase II)
Add 2 priorities to ABC--D E (administer Drugs, Electrical—
defibrillate)
– Drugs (continued)
• 2% Lidocaine (Used to treat cardiac arrhythmias)
– Dogs:
Cats:
1-2 mg/kg
0.5-1.0 mg/kg
• Sodium bicarb (For metabolic acidosis)
– 0.5 mEq/kg per 5 min or cardiac arrest
• Vasopressin (ADH)
– 0.8 U/kg
CPR
Cardiopulmonary Resuscitation
• Advanced Life Support (Phase II)
Add 2 priorities to ABC--D E (administer Drugs, Electrical—defibrillate)
– Drugs (continued)
• Route of drug administration
– Jugular vein—close to heart; drugs will get to heart quicker
– Cephalic, saphenous—follow drugs with 10-30 ml saline flush
– Intraosseous—intramedullary cannula into femur, humerus, wing of ilium,
tibial crest
– Intratracheal—for limited # of drugs: atropine, lidocaine, epinephrine
– Intracardiac—last resort; several complications can occur
• Depends on
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–
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Speed of access
Technical ability
Difficulties encountered
Rate of drug delivery
Cardiopulmonary Resuscitation
• Advanced Life Support (Phase II)
Add 2 priorities to ABC--D E (administer Drugs, Electrical—
defibrillate)
– Electrical—Defibrillate
• Purpose—eliminate asynchronous electrical activity in heart
muscles by depolarizing all cardiac muscle fibers; hopefully, the
fibers will repolarize uniformly and start beating with
coordinated contractions
• Paddles (with electrical gel) placed on each side of chest
• Yell “CLEAR” before discharging electrical current
• Start with low charge and increase as needed
– External: 3-5 J/kg
– Internal: 0.2-0.4 J/kg
Cardiopulmonary Resuscitation
DEFIBRILLATORS
Cardiopulmonary Resuscitation
NORMAL EKG
VENTRICULAR FIBRILLATION
Cardiopulmonary Resuscitation
• Prolonged Life Support (Phase III)
– Once heart is beating on its own, monitor the following:
• HR and rhythm
– Antiarrhythmic drugs
– Correct electrolyte abnormalities
• BP
• Peripheral perfusion
– Color of mm
– Cap refill time
– urine output
• RR and character of breathing
– Adequate breathing
– Auscultory sounds
• Mental status
• Improving or deteriorating
UC Davis study: survival rate at 1 wk for cardiac resuscitation patients
Dogs: 3.8%
Cats: 2.3%
CPR
EDUCATION
“Education is what survives after
what has been learned has been
forgotten.”
- B.F. Skinner
Anaphylaxis/Allergic reactions
Rare, life-threatening reactions to something injected or ingested
Untreated, it results in shock, resp/cardiac failure, and death
IgE Antibodies to allergen bind to mast cells; on subsequent exposure, the Ag-Ab
reaction causes massive release of histamine and other inflammatory mediators
Histamine → vasodilation → ↓BP
• Initiating factors
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Insects
Vaccines
Antibiotics
Certain hormones
Other medications
Foods
Anaphylaxis/Allergic reactions
• Signs
– Sudden onset of vom/diarrhea
– Shock
• Gums are pale
• Limbs are cold
• HR rapid, weak
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Face scratching (early sign)
Respiratory distress
Collapse
Seizures
Coma
Death
Anaphylaxis/Allergic reactions
• Rx (this is an extreme emergency)
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Eliminate cause
Epinephrine
H1 antihistamines (Diphenhydramine)
IV fluids
Corticosteroids
Oxygen
• Prevention
– There is no way to predict what will bring on
an anaphylactic reaction the first time
– Always inform vet if animal has had previous
reaction to vaccine
• Owners should have an ‘epi-pen’ with them at all times
Heat Stroke (Hyperthermia)
Requires immediate treatment
Dogs do not cool as well as humans (don’t sweat)
Evaporate fluid from mouth, tongue, pharynx)
Mortality: 50 – 64%
• Causes
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Left in hot car
Water deprivation
Obesity/older
Chained without shade in hot weather
Muzzled under a hot dryer
Short-nosed breed (esp Pug, Bulldog)/heavy coat
Heart/Resp disease or any condition that impairs breathing or
ability to cool body
– Lack of acclimatization/exercise (takes 45- 60 days to acclimatize)
AN ENLARGED TONGUE HANGING FREELY FROM THE MOUTH IS A
CLEAR SIGNAL TO REST AND COOL
Heat Stroke
• Signs
– Rapid, frantic, noisy breathing
– Tongue/mm bright red, thick saliva
– Vomiting/diarrhea—may be bloody
– Rectal temp >105°
– Unsteady/stagger
– 107 – 108: energy for cellular
functions ceases = Coma/death
Prevention
Heat Stroke
• Complications
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Multi-system organ failure
Denatures proteins
Hypotension
Prognosis: nucleated RBC
Lactic acidosis
Decreased oxygen delivery
Electrolyte abnormalities => cerebral edema and death
Coagulopathies => DIC
If survives the first 24 hrs, prognosis is more favorable
Heat Stroke
• TREATMENT Mild cases: move
dog to a/c building or car
– Temp >104º, immerged in
cool water, hose down, fan,
wet cloths
– Temp >106º, cool water
enema (cool to 103º)
– Temp >109° leads to multiple
organ failure
STOP COOLING EFFORTS
AT 104º
– IV fluids
– Corticosteroids
Emergency Drugs in Cats
Emergency Drugs in Dogs
Pain Management
• Misconceptions about animal pain
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Animals do not experience pain
Pain doesn’t really affect how animal responds to treatment
Signs of pain are too subjective to be assessed
Pain is good because it limits activity
Analgesia interferes with accurate assessment of treatment
Pain management not major concern in LA (except horses)
Pain shows weakness/fragility (Lab vs Collie)
• Fresh ideas about animal pain
– Analgesia increases chance of recovery in critically ill
– Pain associated with diagnostic test should be minimized
– Morally correct thing to do
Pain Management
• Signs
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Vocalization
↑HR
↑RR
Restlessness, abnormal posturing, unwilling to move
↑ Body temperature
↑BP
Inappetence
Aggression
Facial expression, trembling
Depression, insomnia
Pain Management
• Sequelae to untreated pain
– Neuroendocrine responses
• Excessive release of pit, adr, panc hormones
– Cause immunosuppression and disturbances of growth, development, and
healing
– Cardiovascular compromise
• ↑BP, HR, intracranial pressure
– Coagulopathies
• ↑platelet reactivity, DIC
– Long-term recumbency
• Decubital ulcers
– Poor appetite/nutrition
• Hypoproteinemia→slow healing
Pain Management
• Pain Relief
– Nonpharmacologic interventions (differentiate pain vs stress)
• Give relief from:
– Boredom, Thirst, Anxiety, Need to urinate/defecate
•
•
•
•
•
Clean bedding/padding
Reduce light/sound
Stroking pet, calming speech
Owner visits (±)
Minimize painful events (reduce #, improve skills in injections,
blood draw]
Pain Management
• Questions the Vet Tech must continually ask (you are
in charge of pain meds)
– Is patient at acceptable comfort level
– Are there any contraindications to giving pain meds
– What is the appropriate (safe, effective) med for this patient
Pain Management
• Drug Options
– Nonsteroidal Antiinflammatory Drugs (NSAIDs)
•
•
•
•
•
Most widely used
Extremely effective for acute pain
Most effective when used preemptively (before tissue injury)
Usually not adequate to manage surgical pain
COX-2 NSAIDs do not cause damage to stomach lining
– Opioids
• Most commonly used in critically injured animals
– Rapid onset of action; effective; safe
• 4 types of receptors
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μ: analgesia, sedation, and resp depression
Κ: analgesia and sedation
Σ: depression, excitement, anxiety
Δ
• Side effects
– Vomiting, constipation, excitement, bradycardia, panting
• Metabolized by liver; excreted by kidneys
– Use caution with hepatic, renal disease
Pain Management
• Opioids
– Morphine sulfate (great for orthopedic emergencies)
•
•
•
•
Used for max analgesia/sedation
Inexpensive
Side-effects: systemic hypotension, vomiting
Cats particularly sensitive
– Oxymorphone
• 10x potency of morphine
• Much more expensive; less resp depression and GI stimulation
• Side-effects: depression, sensory hypersensitivity
– Hydromorphone
• Similar effects of Oxymorphone
• More widely available, less expensive than Oxymorphone
Pain Management
• Opioids
– Fentanyl citrate
• Extremely potent
• Rapid onset, short duration when administered IM or IV
• Transdermal patch
– 3-day duration
– Shave hair, apply to the skin
– Butorphanol Tartrate
• Κ agonist; μ antagonist
• Analgesic effect questionable (>1 h); good sedative (~2 h)
– More expensive than morphine
– Less vomiting, resp. depression
– Buprenorphine
• Partial mu agonist
• 30x potency of morphine; longer duration
• good absorption via buccal mucosa
Pain Management
• Opioids
– Antagonists
• Naloxone HCl
– Reversal occurs within 1-2 min
– Can be used to reverse anesthesia (Inovar-Vet)
PERSEVERANCE
“Sometimes the best way out is
through.”
TOXICOLOGIC
EMERGENCIES
Toxicologic Emergencies
• Signs will vary depending on character of toxic
compound
• Toxicity can result from exposure via many routes
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–
–
Ingestion
Inhalation
Skin contact
Injection
Toxicologic Emergencies
• Top 10 Toxicoses (2005)
– Human medication (ibuprofen, acetominophen, antidepressants)
– Insecticides—flea and tick
– Rodenticides—anticoagulants
– Veterinary medication
– Household cleaners—bleach, detergents
– Plants—sago palm, lily, azalea
– Herbicides
– Chocolate—highest in food category
– Home improvement products—solvents, adhesives, paint,
wood glue
– Fertilizers
Toxicologic Emergencies
• HISTORY
• ASSESS
• STABILIZE
– Administer oxygen
– Control seizures
– Correct cardiovascular abnormalities
• DECONTAMINATION
– Emetics
– Activated charcoal
– Gastointestinal protectants
• CONTROL CLINICAL SIGNS
• GOOD NURSING CARE
• PREVENT FURTHER EXPOSURE
Toxicologic Emergencies: external exposure
• Ocular exposure
• Rinse eyes with copious saline for 20-30 min
• Chemical burns treated with lubricating ointment and
suture lids closed
– Use corticosteroids only if corneal epithelium is
intact
– Skin exposure
• Bathe with mild detergent (liquid dish soap)
• Bather should wear protective clothing (gloves, goggles)
TO VOMIT OR NOT TO
VOMIT?
VOMIT
•
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Acetone
Alcohol
Amphetamines, opiates, cocaine, heroin
Arsenic
Snail or rat bait
Marijuana, tobacco, cigarettes/cigars
Pesticides and insecticied i.e. malathion,
dichlorvos, diazonon
House plants and sago plants
Lead
Pine oil
Choclate
Xylitol containing food items
•
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DO NOT VOMIT
Petroleum distillates
Sharp objects
Bread dough
Commercial or industrial cleaners
Alkali/ caustic cleaners
Bleach
Burnt lime
Volatile substances i.e. gasoline or paint
thinner
Unknown chemicals
Fertilizers
Lye (NaOH/ caustic soda)
Gorilla glue
Strychine
Toxicologic Emergencies
• Ingestion
• Induce vomiting—if chemical not caustic; animal conscious, not
seizing
– Syrup of ipecac, apomorphine, Xylazine, H2O2 (not reliable), salt (not
recommmended)
• Dilute caustic substances with milk, water
• Gastric lavage—large bore stomach tube; light anesthesia w/
endotracheal tube
• Administer absorbents—activated charcoal inhibits GI absorption
– Give orally or via stom tube
• Enemas/cathartics to eliminate toxins more rapidly
Toxicological Emergencies
ACTIVATED CHARCOAL WITH OR WITHOUT A CATHARTIC
Toxicologic Emergencies
•
Methylxanthines (caffeine,
theobromine, theophylline
– Found in: coffee, tea, chocolate,
other stimulants
•
•
Toxic Dose of caffeine and theobromine in dogs:
100-200 mg/kg; (other sources: 250-500mg)
Milk Chocolate—44-60 mg/oz
Dark chocolate-150 mg/oz
Baking Chocolate—390-450 mg/oz
Toxicologic Emergencies
• Clinical signs of methylxanthine/chocolate
toxicosis (caffeine, theobromine)
–
–
–
–
–
Increased HR, RR
Anxiety
Vomiting/diarrhea
Seizures, coma
Cardiac arrhythmias
• Treatment
–
–
–
–
Induce vomiting
Activated charcoal
Control seizues
Fluid therapy
Toxicologic Emergencies
– Rodenticides
1. Anticoagulants
(warfarin,
pindone,
bromadiolone,
brodifacoum)
– Work by binding Vit K,
which inhibits synthesis
of factors II, VI, IX, X
– This effect occurs
within 6-40 h in a dog;
effect may last 1-4 wk
Toxicological Emergencies
• Clinical signs (occur after depletion of clotting factors)
–
–
–
–
–
–
Lethargy
Vom/dia with blood; melena
Anorexia
Ataxia
Dyspnea
Epistaxis, scleral hemorrhage, pale mm
• Treatment
– Vit K: 3-5 mg/kg PO for up to 21 d depending on anticoagulant
used
– Induce vomiting; activated charcoal
– Whole blood transfusion if anemic
Toxicologic Emergencies
– Rodenticides
2. Cholecalciferol—Vit D3; used in Quintox,
rampage, Rat-Be-Gone
-causes Ca++ reabsorption from bone, intestine, kidneys
causing hypercalcemia (>11.5 mg/dl) and cardiotoxicity
• Clinical signs (12-36 h after ingestion)
– Kidney failure
» Anorexia
» Vomiting
» Tissue mineralization
– Cardiovascular abnormalities
» Muscle weakness
» arrhythmias
Toxicological Emergencies
• Diagnosis
– Hx of exposure
– Usually discovered on routine Chem panel (↑blood Ca++)
• Treatment
– Induce vom/activated charcoal if ingestion occurred with
2h
– Furosemide x 2-4 wk; increases Ca++ excretion in urine
– Prednisone x 2-4 wk; decreases Ca++ reabsorption from
bones/intesine
– Calcitonin to lower blood Ca++ concentration
Toxicologic Emergencies
–
Rodenticides
3. Bromethalin
-uncoupler of oxidative phosphorylation in CNS (stops production of
ATP)
-Causes cerebral edema
-found in Assault, Vengence, Trounce
-Toxic Dose
Dog: 4.7 mg/kg
Cats: 1.8 mg/kg
Clinical signs (>24 h after ingestion of high dose; 1-5 d-low dose)
•
–
–
Excitement, tremors, seizures
Depression, ataxia
Rx (will take 2-3 wk to know if animal will survive)
–
–
–
Purge GI tract if exposure recent
Reduce cerebral edema with Mannitol and glucocorticoids
Seizure control with Diazepam and Phenobarbital
Toxicologic Emergencies
• Acetaminophen
• Common OTC drug for analgesia
• Toxic dose:
Dog—160-600 mg/kg
Cat—50-60 mg/kg (2 doses in 24 h is almost always
fatal)
• Clinical signs (starts within 1-2 h of ingestion)
–
–
–
–
–
–
Vomiting, salivation
Facial and paw edema
Depression
Dyspnea
Pale mm
Cyanosis due to methemoglobinemia
• Px—poor
• Rx
– Induce vom/activated charcoal
– Antidote: N-Acetylcysteine (loading dose of140-280 mg/kg PO, IV, then
at 70 mg/kg PO, IV QID x 2-3 d
Toxicological Emergencies
causing the blood to be dark brown in color
Toxicologic Emergencies
– Metals
• Lead toxicity more common in dogs than cats
– Source
» Lead paint (prior to 1970’s) is primary source
» Batteries, linoleum, plumbing supplies, ceramic
containers, lead pipes, fishing sinkers, shotgun pellets
– Clinical signs (Usually involves signs of GI and nervous
systems)
» Anorexia
» Vom/dir
» Abd pain
-CNS signs do not show initially
» Blindness, seizures, ataxia, tremors, unusual behavior
Toxicologic Emergencies
– Metals
• Lead toxicity
– Dx
»
»
– Rx
»
»
Large # nucleated RBC’s; basophilic stipling
Blood lead conc >35 μg/ml
Remove lead from GI tract (cathartic, Sx)
Chelators (to bind the Pb in blood stream and hasten its
removal)
-Calcium EDTA (ethylene diamine tetra acetic acid)
-Penicillamine
» IV fluids for dehydration and to speed removal via kidneys
» Diazepam, Phenobarbital to control seizures
Toxicologic Emergencies
– Metals
• Zinc Toxicosis
– Usually from ingested pennies, galvanized
metal, zinc oxide ointment
• Clinical signs
– Vomiting
– CNS depression
– Lethargy
• Dx
– Hx of exposure
– Clinical signs
• Rx
– Remove metal objects endoscopically or
surgically
– IV fluid therapy
– Ca EDTA chelation
Toxicologic Emergencies
• Ethylene Glycol (antifreeze; sweet taste)
• Lethal dose:
Cat—1.5 ml/kg
Dog—6.6 ml/kg
• Signs (onset within 12 h of ingestion)
–
–
–
–
–
• Dx
CNS depression, ataxia (may appear intoxicated)
Vomiting
PD/PU
Seizures, coma, death
Acute renal failure
– Hx, signs
– Ethylene Glycol Poison Test—an 8 min test used in cats and dogs
– Calcium oxalate crystals
• Rx
– Emesis, adsorbents if ingestion within 3 h of presentation
– IV fluids, NaBicarb for acidosis
– Ethanol inhibits ethylene glycol metabolism Dogs (Cats): 20% ethanol—5.5 (5.0)
ml/kg q6h x 5, then q8h x 4
– 4-methylpyrazole has been shown to be effective
Toxicological Emergencies
THE PROBLEM
THE SOLUTION
Toxicologic Emergencies
• Snail Bait (Metaldehyde, methiocarb)
– Metaldehyde mechanism unknown
– Methiocarb is a carbamate and parasympathomimetic
• Signs
–
–
–
–
–
–
Hypersalivation
Incoordination
Muscle fasciculations
Hyperesthesia
Tachycardia
Seizures
• Rx
– Emesis and absorbents
– Pentobarbital, muscle relaxants to control CNS hyperactivity
Toxicologic Emergencies
• Garbage Toxicity
– Common in dogs; not in cats
– Enterotoxin-producing bacteria include
Strep, Salmonella, Bacillus
• Signs (within min to h after ingestion)
–
–
–
–
Anorexia, lethargy
Vom/dia
Ataxia, tremors
Enterotoxic shock can cause death
• Rx
–
–
–
–
–
IV Fluid therapy
Broad-spec antibiotics
Intestinal protectants
Muscle relaxers or Valium may be needed to control tremors
Corticosteroids to counter endotoxic shock
Toxicologic Emergencies
• Insecticides
• Pyrethrins, Pyrethroids, Permethrins
– Common ingredients of flea/tick sprays, dips, shampoos, etc
– If used according to instructions, toxicity rarely occurs; if overused,
toxicity can result
• Signs
–
–
–
–
Hypersalivation
Vom/dia
Tremors, hyperexcitability or lethargy
Later, dyspnea, tremors, seizures can occur
• Rx
–
–
–
–
–
Bathe animal to remove excess
Induce vomiting/charcoal/cathartics for ingestion
Diazepam may be necessary for mild tremors
Methocarbamol, a muscle relaxer, for moderate-severe tremors
Atropine for hypersalivation and bradycardia
Toxicologic Emergencies
– Insecticides
• Organophosphates and Carbamates
– Inhibit cholinesterase activity (break down of Ach is inhibited)
– Highly fat-soluble; easily absorbed from skin and GI tract
– Found in dips, sprays, dusts, etc for fleas and ticks, and flys
• Signs
– Salivation
– Lacrimation
– Urinary incontinence
– Diarrhea
– Dyspnea
– Emesis, gastrointestinal cramping
-May progress to
– Seizures, coma, resp depression, death
• Rx
–
–
–
–
Bathe animal
Charcoal if ingested
Atropine (0.2-0.4 mg/kg; half IV, half IM or SQ)
Praloxime chloride (20 mg/kg BID till signs subside)—reactivates
cholinesterase
Toxicologic Emergencies
• Plant Toxicity
–
–
–
–
Most common in confined and juvenile animals
Usually from ornamental, indoor plants
Severity varies with plants
ID scientific plant name (florist, greenhouse)
• Araceae family (most from this family)
– Dumb cane, split-leaf philodendron
– Contain calcium oxalate crystals
• Signs
– Hypersalivation, oral mucosal edema, local pruritis
-Large amount of plant may cause:
– Vomiting, dysphagia, dyspnea, abd pain, vocalization, hemorrhage
• Rx
– Rinse mouth with milk or water to remove Ca Oxalate crystals
– GI decontamination (protectants) may be needed
Dumb Cane (Dieffenbachia)
• aka Mother-in-law’s tongue
• Oral irritation; intense burning,
excess salivation
Split Leaf Philodendron
• Oxalate crystals like Dieffenbachia
• Oral irritation; intense burning, excess salivation
Lily of the Valley
• Contains cardiac glucosides
• Cardiac arrythmias, death
Azalea (Rhododendron)
• Hypotension, cardiovascular collapse, death
Sago Palm
• ALL PARTS OF THE PLANT ARE TOXIC
• Coagulopathy
• Liver failure
Toxicologic Emergencies
• Phone advice to give owners (legal issues)
– Protect yourself from exposure before handling animal
• Gloves, protective clothing
– Protect yourself from animal because poisoned animals may
act strangely
– Protect animal from further exposure by removing pet from
source
– Bring sample of vomit, feces, urine
– Bring container/package that toxin was in and a sample of the
toxin (plant material, rat bait, etc)
References
• Alleice Summers, Common Diseases of
Companion Animals
• Texas A and M University, 2nd Annual Canine
Paramedicine Conference, May 2011
• http://veterinarymedicine.dvm360.com/vetmed
/ArticleStandard/Article/detail/670169