A 78-year-old male has been transported to your facility via EMS. You observe the skin is cyanotic, blue and diaphoretic. His level of consciousness is severely reduced. He is only responding to uncomfortable stimulation. The paramedics report his blood pressure is 42/0 with a weak radial pulse of 28. When placed on the ECG monitor, you see a wide-QRS 3rd degree AV block.
Oxygen is administered and transcutaneous cardiac pacing patches are attached to the patient’s chest. Pacing is initiated at 20mA without capture. The amperage is increased incrementally until capture is observed at 110 mA. Within a minute, the patient’s level of consciousness improves and he is showing signs of discomfort on each TCP discharge. Morphine sulfate is given in 2.0 mg increments until the patient becomes comfortable.
The patient is prepared for insertion of an emergency transvenous cardiac pacemaker.
ADDITIONAL QUESTIONS
4. Atropine is always the first-line drug of choice when treating any bradycardia.
A. True
B. False
The best answer is B, False.
5. Which of the following might be improved by using atropine?
A. Sinus bradycardia
B. 1st degree AV block
C. 2nd degree AV block type I
D. All of the above
The best answer is D, All of the above.
6. The recommended dose of I.V. atropine used to treat symptomatic bradycardia is:
A. 0.4 mg IV bolus repeated every 10-15 minutes as needed
B. 0.5 mg IV bolus every 3-5 minutes as needed
C. 2 mg IV bolus, may repeat as necessary
D. Any of the above are acceptable
The best answer is B, 0.5 mg IV bolus every 3-5 minutes as needed.
7. When treating symptomatic bradycardia in adult patients, epinephrine should only be used by careful titration of an infusion, never by bolus.
A. True
B. False
The best answer is A, True.
8. Both epinephrine and dopamine titrated infusions are recommended as follows: 2 – 10 mcg/kg/min.
A. True
B. False
The best answer is A, True.
Case Study #3: Tachypnea
EMS has transported a 41-year-old woman who they state was found walking down a road totally disoriented and unable to identify herself. A family member arrived and informed the staff that the patient was an avid runner and other than muscle pains related to that activity had made no other complaints about her physical state. VITAL SIGNS: BP=140/70 mm Hg, RADIAL PULSE= 122/minute, RESPIRATORY FREQUENCY=31/minute (with no signs of increased work of breathing), and her PULSE-OX=96% (FI02=.21).
Her general physical exam was essentially negative except for the confusion, and the tachypnea. Her blood glucose level (meter) was normal. URINALYSIS: S/G=1.022, pH=5.54, 3+ ketones, and 3+ protein. 12-lead electrogram = normal sinus tachycardia. An APLateral chest radiograph showed scattered patchy infiltrates bilaterally. The patient was admitted with a diagnosis of acute pneumonia and IV antibiotics were started.
FURTHER ASSESSMENT
After admission, an ABG was obtained due to the continuing tachypnea. The results were: pH-7.47, paC02-25 mm Hg, pa02-61 mm Hg (FIO2=21%). The nursing staff noted the odor of “wintergreen” on the patient. Based on the above, blood was sent to the lab to obtain a salicylate level, which came back at 66 mg/dl. The patient reported that she had been using large amounts of topical liniment and P.O. aspirin over the last 4 days to manage back and lower extremity pain.
QUESTIONS
1. What is your diagnosis?
A. Acute salicylate intoxication
B. Bilateral pneumonia
C. Spontaneous pneumothorax
D. Severe anxiety reaction
The best answer is A, Acute salicylate intoxication.
2. What is the best course of treatment for this patient?
A. Antibiotic therapy
B. Inhaled bronchodilator
C. Emergency hemodialysis
D. A chest tube
The best answer is C, Emergency hemodialysis. This patient received emergency hemodialysis and within 4-6 hours had normalized mental status and lab values.
3. What is the primary blood gas derangement seen with acute salicylate intoxication?
A. Hypercarbia with metabolic alkalosis
B. Hypercarbia with no metabolic changes
C. Mixed respiratory alkalosis with metabolic acidosis
D. Severe hyperoxia
The best answer is C, Mixed respiratory alkalosis with metabolic acidosis.
4. It is important to assess patients presenting with salicylate intoxication considering whether it is acute or chronic.
A. True
B. False
The best answer is A, True.
5. Sodium bicarbonate therapy is safe and always recommended.
A. True
B. False
The best answer is B, False.
6. Other than measuring serum salicylate levels, what laboratory result should cause a practitioner to consider salicylate intoxication?
A. Elevated anion gap
B. Highly elevated serum calcium
C. Highly elevated serum glucose level
D. None of the above
The best answer is A, Elevated anion gap.
7. Aspirin is the only substance which produces clinical salicylate toxicity.
A. True
B. False
The best answer is B, False.
IMPORTANT FACTS ON ACUTE SALICYLATE INTOXICATION
- According to the CDC, products containing salicylates account for about 15% of annual analgesic-related deaths each year.
- Aspirin is not the only problematic agent. Methyl salicylate compounds used topically cause unintentional exposure.
- Pepto-Bismol has 8.7 mg of salicylate per ml.
- Salicylates have widespread effects on the human body. Tinnitus, gastric disorders, hyperthermia, anion-gap metabolic acidosis, non-cardiogenic pulmonary edema, cerebral edema, seizures and death have been reported.
- The most common diagnosis pathway is the presence of an elevated serum salicylate level. It is important to obtain clear, accurate history which would lead to the possibility. Also, chronic toxicity may show lower than expected level elevation, making the assessment of the patient’s symptoms essential in determining the level of intoxication.
- Initial management is airway/ventilation/IV access.
- Aspirin is well bound by activated charcoal.
- Ipecac is NO longer recommended.
- Some consider serum alkalization with NaHC03 (guard against severe alkalemia).
- Hemodialysis may be considered in cases where there is: persistent severe electrolyte and/or acid-base disturbances failing to respond to aggressive therapy, cerebral or pulmonary edema, progressive clinical decline. Some texts suggest that dialysis should occur at serum salicylate levels >90 mg/dL (acute) and >60 mg/dL (chronic). Most experts agree dialysis should be considered in very ill patients.
Case Study #4: Recurrent Ventricular Fibrillation
A 72-year-old male develops coarse ventricular fibrillation while being monitored following an uneventful colonoscopy. He is immediately defibrillated using a biphasic defibrillator at 120 joules. The counter-shock is successful and he is converted to sinus tachycardia. He has resumed spontaneous breathing.
Forty-five seconds later, he again develops ventricular fibrillation. He is shocked once again using 120 joules. This causes conversion back to sinus rhythm and he resumes breathing. His ventilation is assisted using a bag/valve/mask device with supplemental oxygen.
Several minutes later, ventricular fibrillation reoccurs. Immediate countershock at 120 joules terminates the fibrillation and he is back in sinus tachycardia with a pulse.
QUESTIONS
1. Should epinephrine or vasopressin be administered?
The indication for using a vasopressor such as epinephrine and/or vasopressin is refractory ventricular fibrillation (VF that does not respond to countershock). In this case, administering agents that may be proarrhythmic would be a poor choice.
2. Should the delivered energy be increased with subsequent shocks?
More therapeutic energy may be needed when a patient fails to respond at a lower level. However, in this case the patient responded well to each shock delivered. The problem was not refractoriness to the therapy. This patient kept having spontaneous reinduction.
3. Should antiarrhythmic drug therapy be considered?
Drugs such as lidocaine, procainamide, and amiodarone have been shown to increase the induction threshold for ventricular arrhythmias. With this in mind, use of such agents may make clinical sense. Issues such as onset of action, difficulty in establishing rapid blood levels, and whether or not ischemia is a component should be considered.
4. What clinical situations might explain recurrent ventricular fibrillation?
There are many clinical possibilities for chronic reinduction of arrhythmias. Some might include: - Ongoing ischemia - Organic cardiac damage - Electrolyte imbalance - Practitioners should seek to find the underlying cause and correct the problem as quickly as possible in order to improve the patient's outcome.
Conclusion
We hope you had fun and were challenged while reviewing these four case studies in preparation for your ACLS certification exam. Keep in mind that this guide is not intended to be a replacement for studying the ACLS Provider Manual. For additional ACLS training online, including our Diagnostic Skills Challenge, visit the Exam Prep page on our website.
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