Week 11 - Chemical Injuries Flashcards
what conditions happen/occur at phase 3 acetaminophen overdose?
Encephalopathy (a disease in which the functioning of the brain is affected by some agent or condition (such as viral infection or toxins in the blood).
, renal failure,
cardiomyopathy (Cardiomyopathy is a disease that affects your myocardium (heart muscle). Cardiomyopathy can make your heart stiffen, enlarge or thicken and can cause scar tissue. As a result, your heart can’t pump blood effectively to the rest of your body.)
When do Serum acetaminophen levels peak after injestion?
Serum acetaminophen levels peak at 4 hrs after injestion?
Classic symptoms for Downers? (what substances to these apply to?) (5 of them)
Applies to opioids, benzos, alcohol
Respiratory depression
Pupil constriction
Bradycardia
Hypothermia
Coma
What is something that was found to be a key contributing factor to overdose deaths?
polysubstance use was found to be a key contributing factor to overdose deaths.
What kind of symptoms do “All Arounders” produce when they are used/abused? What is an example of an “All Arounder”?
These drugs produce mixed symptoms when used or abused!
*Ecstasy, for example, is chemically very similar to cocaine and particularly methamphetamine (is a derivative of meth), but ecstasy produces hallucinogenic symptoms in addition to those on the “uppers: classic symptoms slide!
What do we need to watch for when using Cathartic/emetic methods to prevent the absorption of a substance?
*Electrolyte imbalances/dehydration
What is the main guide and basic principles of managing overdoses?
Remember, ABCDEs are still the guide and basic principles of managing overdoses still apply
Examples of substances that are combined/used as polysubstance? (think more street drugs)
Some substances named included “alcohol, fentanyl, methadone, cocaine, carfentanil, hydromorphone, benzodiazepines, morphine, heroin, and methamphetamines (note that this is not an exhaustive list)”
What do we need to watch for when using Gastric suctioning or lavage to prevent the absorption of a substance?
*Electrolyte imbalances/dehydration because we are removing fluids from the body
Why would we use Benzos + IV sodium bicarbonate to treat Salicylate Overdoses?
Benzodiazepines (prevent seizures)
IV sodium bicarbonate - Alkalinization of Urine – promote urine excretion and correct acidosis- NaHCO3 +/- potassium to promote urinary excretion and correct acidosis (watch for alkalosis!)
With any suspected overdose what is/are still our main initial focus?
With any suspected overdose, the principles of ABCDE still apply and are still our main initial focus
-Management of ABCDE!!!
For Salicylate overdoses, what does Free drug in extracellular space lead to/cause? (think of 4 S+S)
Free drug in the extracellular space can lead to confusion, delirium, seizures, coma
With acetaminophen overdoses, when is Hepatotoxicity/overdose more likely to occur?
Hepatotoxicity is more likely to occur with:
-Older adults
-Children/adults <50kg
-Malnourished patients
-Higher doses of ingestion
-Doses taken over shorter time frame
-Prexisting liver disease
-Taken with other hepatotoxic meds (amoxi-clav, carbamazepine, erythromycin
Hepatotoxicity is more likely with older adults, children and adults <50kg, malnourished patients, higher doses of ingestion, doses taken over a shorter time frame, patients taking medications that are also hepatotoxic, or preexisting liver disease.
Treatment for opioid overdose?
Treatment: activated charcoal and naloxone (IM or IV, intermittent or continuous)
S+S of a MILD Salicylate Overdose? (4 main ones), what is the Amount of ASA in Bloodstream at this level?
ASA Blood level: >150mg/kg
S+S: Nausea, vomiting, dizziness, tinnitus
What makes polysubstance ( multiple substance) use dangerous for overdoses? What do they pose for health care providers?
Combining these substances makes fatal overdoses more likely and poses a significant treatment challenge for practitioners
For Salicylate overdoses, what does the patients prognosis depend on?
Prognosis depends on patient age and amount consumed over time
Examples of uppers, downers, and all arounders?
-“Uppers”
Cocaine, methamphetamine, caffeine, nicotine
-“All Arounders”
Ecstasy, marijuana, psilocybin (magic mushrooms), LSD, PCP, peyote
-“Downers”
Alcohol, opioids, benzodiazepines, tranquilizers
what is the #1 reason for liver transplantation?
Acetaminophen overdoses
What key intervention do we do if acetaminophen levels OR liver function tests increase? (does it need to be both tests?) When is it especially important we do these?
Key: Mucomyst IV initiated if acetaminophen levels OR liver function tests increased (doesn’t need to be both—esp important if time of ingestion is unknown)
Example of Cathartic/emetic methods (medications) we can use to prevent the absorption of a substance?
-Epecac (vomiting) / Magnesium Citrate/sulfate (laxative)
S+S of acetaminophen overdose? (Phase 4) how long does this phase last for?
Fourth phase: 5-7 days
Resolution of liver function, or Death
-You wither get better or die!
What are Important questions to ask when trying to identify the substance for an overdose patient?
Important questions to ask: what was ingested, how much, at what time, have they taken this before?
Treatment for Salicylate Overdoses? (what kind of treatment is necessary?) (6 different interventions)
Aggressive treatment necessary!!!
1.) Address ABCDEs
Possible intubation - Protect airway or control respirations
2.) IV fluids
Dehydration and dextrose (for decreased glucose levels) and possible dextrose containing fluids for glucose depletion
3.) IV sodium bicarbonate
Alkalinization of Urine – promote urine excretion and correct acidosis
-NaHCO3 +/- potassium to promote urinary excretion and correct acidosis (watch for alkalosis!)
4.) Activated charcoal (prevent further absorption) - Can be administered several times!
5.) Benzodiazepines (prevent seizures)
6.) Hemodialysis possible but uncommon
What phase of acetaminophen overdose do the most sevre and worst symptoms come out? (how does the liver play a centeral role?)
Phase 3 - This is where the most severe symptoms come out!!!!
The liver plays a central role in this process bybalancing the uptake and storage of glucose via glycogenesis and the release of glucose via glycogenolysis and gluconeogenesis.
Examples of overdoses with multiple substances!
Many patients overdose on multiple substances, intentionally or unintentionally
E.g. high on cocaine and drunk on alcohol
E.g. ecstasy laced with methamphetamine
E.g. polypharmacy in the elderly
S+S of phase 1 of an acetaminophen overdose? (7 of them) how long does this phase last for? What intervention do we do here to confirm acetaminophen levels?
First Phase – 1st 24 hrs
-Nonspecific
-Nausea, vomiting, anorexia, pallor, lethargy, diaphoresis, OR
-Asymptomatic
-Liver Function Tests usually normal
-Blood levels of acetaminophen confirmed
What does Acetaminophen overdoses result in?
Results in profound hepatotoxicity!!!
-Metabolized in liver
-Reactive/toxic metabolites that damage liver
-#1 reason for liver transplantation
S+S of a SEVERE Salicylate Overdose? (think of the big one!), what is the Amount of ASA in Bloodstream at this level? (7 main ones we went over in class)
ASA Blood level: >500mg/kg
S+S: Hypotension, metabolic acidosis, cerebral edema, oliguria(low urine output), renal failure, coma, seizures
What are some interventions we can do to prevent absorption? (what is the best timeframe for these interventions to be done ? Why?)
1.) Activated charcoal:
NG into stomach
Binds with substances to prevent absorption
2.) Gastric suctioning or lavage (pump the patients stomach)
NG to suction (can’t remove large pills)
Can instill fluids before suctioning
*Electrolyte imbalances/dehydration
3.) Cathartic/emetic
Give meds to induce vomiting or GI motility (emptying stomach of unabsorbed substances)
-Epecac (vomiting) / Magnesium Citrate/sulfate (laxative)
*Electrolyte imbalances/dehydration
All best done within 60-minutes of ingestion - any longer and there is limited clinical benefit since the drug has been absorbed
How does the liver play a centeral role with acetaminophen overdoses?
The liver plays a central role in this process bybalancing the uptake and storage of glucose via glycogenesis and the release of glucose via glycogenolysis and gluconeogenesis.
How do we Identify the Poison/Substance for an overdose?
Health history – what was ingested, how much, at what time, have they taken this before?
Blood levels – etoh, THC, cocaine, etc.
S+S of a MODERATE Salicylate Overdose? (7 of them), what is the Amount of ASA in Bloodstream at this level?
ASA Blood level: >250mg/kg
S+S: Tachypnea, hyperpyrexia (>41C), sweating, dehydration, agitation, ataxia (poor muscle control), restlessness
Ex of unintentional overdose?
Unintentional are more common, but not exclusive to, the elderly.
Sometimes the patient can tell us what they took (especially if it is intentional), or at least give us clues (e.g. “I take a medication for my heart rate”—what is it and does their clinical picture correlate to taking too much of it?).
Sometimes family members find empty bottles—more clues for us.
What are important blood tests we run for acetaminophen overdoses?
Important blood tests: acetaminophen levels (illustrated on slide), AST/ALT (liver function)
What are some interventions we can do to enhance excretion of a substance? (3 of them)
1.) Hemodialysis
Rare
Filter the blood to remove toxins
Dialysis is rare and generally only for the critically ill, but it can filter the blood and potentially remove toxins
2.) Fluid loading
Enhance kidney/liver function
Excrete drug quicker (if via kidneys)
Dilute drug
Maintain kidney function
3.) Sodium bicarbonate
-Salicylate and Phenobarbital overdoses
-Alkalinazation of urine enhances excretion of acidic drugs
-Given via IV
In a select few cases, alkalinazation of the urine with sodium bicarbonate can enhance the excretion of acidic drugs. Aspirin overdose and phenobarbital overdose are the two cases where this could be used. Would be given IV with the goal of urine pH >7.5
General S+S of Salicylate overdose?
Hyperventilation, sweating, and GI losses from vomiting/diarrhea cause dehydration (think metabolic acidosis), confusion, delirium, seizures, coma
When looking at enhancing excretion, what kind of drugs does the alkalization of urine enhance?
Alkalinazation of urine enhances excretion of acidic drugs
What medication/drug is the leading case of of intentional and unintentional overdose in adults? Why? (4 reasons why)
Acetaminophen!!!!
Why: Because it’s so common
1.) Found in many cough, cold, flu and decongestant medication
2.) Over the counter—easily available and accessible in overdose amounts
3.) Patients sometimes think that if 2 pills are good, 4 pills must be better
4.) Lack of recognition of the name acetaminophen (e.g. cold medicine without Tylenol in the name)
What levels usually rise later in the course of an acetaminophen overdose?
LFTs (liver function tests) usually rise later in the course of overdose as acetaminophen levels decrease / are undetectable
S+S of acetaminophen overdose? ( 5 of them) (Phase 3) how long does this phase last for?
Third phase: 72-96 hrs (3-5 days)
-Acute hepatic necrosis
-Fulminant hepatic failure
-Most severe symptoms:
1.) Jaundice,
2.hypoglycemia,
3.stupor (Stupor is an excessively deep state of unresponsiveness, People can be aroused from it only briefly by vigorous stimulation, such as repeated shaking, loud calling, or pinching) ,
4.hemorrhage,
5.liver failure
3 major conditions: Encephalopathy, renal failure, cardiomyopathy
In Salicylate and Phenobarbital overdoses, what is given/what intervention is done to enhance excretion?
Sodium bicarbonate
What is the main condition that Salicylate overdoses lead to/cause? Why?
METABOLIC ACIDOSIS due to the inhibiting of the Krep cycle which then leads to lactic acid build-up which then causes us to hyperventilate
For Salicylate overdoses, what does the inhibit/interference with the Kreb cycle impact? (think outside/other then metabolic acidosis) What does it result in?
Liver can only metabolize so much salicylate per hour, eventually becomes overwhelmed and damaged by metabolites
Interference with Kreb’s cycle also impacts glucose homeostasis: -glycogen depletion
Gluconeogenesis, Catabolism of proteins and free fatty acids as a result - Low serum glucose clinically (hypoglycemia)
What makes acetaminophen over doses unique/different?
Acetaminophen overdose is an interesting phenomenon, because it isn’t the drug itself that kills the person, and it doesn’t kill them right away—they actually start to feel better in the 1-3 day range,
However, they may have caused irreparable liver damage at this point, and so they start to decline a few days later and may still die.
What is the max daily dose for acetaminophen? At what does does overdose symptoms begin to occur?
4g max daily dose
Overdose symptoms start at 10g – as few as 15 Tylenol Arthritis pills (650mg each).
For Salicylate overdose, can we administer activated charcoal several times?
YES
What are the 5 goals/Phases of Treating Overdoses / Chemical Injuries?
1.) Assess and manage ABCDE’s
2.) Identify poison/substance
3.) Prevent absorption
4.) Counteract the substance
5.) Enhance excretion
Why is activated charcoal called activated charcoal?
If they ask, it’s called activated charcoal because it is treated with oxygen to open up microscopic pores in the carbon that act like a sponge
What are Toxidromes?
Toxidromes : a group of signs and symptoms constituting the basis for a diagnosis of poisoning/overdose
*A toxidrome is a constellation of findings, either from the physical examination or from ancillary testing, which may result from any poison/overdose.
group of symptoms based on below classifications
-Acetaminophen
-Salicylates
-“Uppers”
Cocaine, methamphetamine, caffeine, nicotine
-“All Arounders”
Ecstasy, marijuana, psilocybin (magic mushrooms), LSD, PCP, peyote
-“Downers”
Alcohol, opioids, benzodiazepines, tranquilizers
Other than Respiratory depression, Pupil constriction, Bradycardia, Hypothermia, and Coma, what is “other” S+S are there for alcohol intoxication? (7 main ones and also think about CIWA!!)
-euphoria,
-Inhibition (a feeling that makes one self-conscious and unable to act in a relaxed and natural way)
-loss of coordination,
-poor judgment,
-memory loss,
-nausea/vomiting,
-lethargy
What intervention is essential to enhance liver and kidney function? (Hint: it enhances excretion)
In order to enhance liver and kidney function, ensuring adequate hydration (oral or more likely IV fluids) is essential
Classic S+S for Uppers? (7 main ones) What other drug are these symptoms true for as well?
-Tachycardia
-Hypertension
-Dilated pupils
-Diaphoresis
-Hyperthermia
-Agitation
-Combativeness
-(these are true of ecstasy as well)
For Salicylate overdoses, what blood tests would we run? Why do we need to use blood level tests cautiously?
Use blood test levels cautiously—they do not always accurately reflect toxicity.
You will do a series of blood salicylate levels and ABGs to watch that results are trending towards normal
What does Salicylate overdoses inhibit/lead to? What else occurs?
Inhibition of Kreb’s cycle -> this activates anaerobic metabolism lactic acid buildup -> meatabolic acidosis!
Metabolic acidosis - Hyperventilation
Glycogen depletion also occurs - hypoglycemia
S+S of acetaminophen overdose? (Phase 2) how long does this phase last for? What is important to note/remeber for this stage?
Second phase – 24-72 hrs (1-3 days)
-Patient feels better
-Elevation in liver function enzymes *AST and ALT, bili, INR(PT) elevated
-RUQ pain with nausea/vomiting
*However, they may have caused irreparable liver damage at this point, and so they start to decline a few days later and may still die.
Assuming there are no threats to life from ABCDE’s, what is the next thing/step we do when treating overdoses? Why?
Assuming there are no threats to life from ABCDE’s, the next thing to do is to try to identify the substance (or substances) that the patient has in their system. This allows us to direct our treatments more specifically
What is the antidote for acetaminophen overdoses?
acetylcysteine (mucomyst)
What are Cocaine, methamphetamine, (as well as ecstasy) considered? What do they mimic and activate? Our patients and their bodies are?
Cocaine, methamphetamine, as well as ecstasy, are all sympathomimetics
They mimic and activate the sympathetic nervous system. Patients and their bodies are high energy
What is the goal of the Pre-toxic, Toxic, and Resolution Phase when treating overdoses? (remeber, these apply to the 5 prinicples/goals of treating an overdose)
Pre-toxic phase: Goal – limit further absorption or hasten drug elimination.
Toxic Phase: Goal - Minimize tissue/organ injury
Resolution Phase: Goal – Regain homeostasis in organ function and prevent further drug poisoning
