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ACLS Pretest and Answers Part 2

7/28/2023

ACLS Pretest and Answers Part 2
https://youtu.be/_HMkPnLQQ5s

ACLS Pretest and Answers Part 1

7/28/2023

ACLS Pretest and Answers Part 1
https://youtu.be/lx7OuankMes

ACLS guidelines highlights

7/28/2023

https://youtu.be/2_yroF1QiP0

ACLS Guidelines Highlights:

Laypersons should initiate CPR for presumed cardiac arrest.
Evidence shows that the risk of harm to a victim who receives chest compressions when not in cardiac arrest is low.
Lay rescuers are not able to determine with accuracy whether a victim has a pulse, and the risk of withholding CPR from a pulseless victim exceeds the harm from unneeded chest compressions.
For cardiac arrest with a non-shockable rhythm, it is reasonable to administer epinephrine as soon as feasible.
For cardiac arrest with a shockable rhythm, it may be reasonable to administer epinephrine after initial defibrillation attempts have failed.
Randomized trials showed that epinephrine increased ROSC and survival rates.
Audiovisual feedback devices during CPR may optimize CPR performance.
A recent randomized control trial reported a 25% increase in survival to hospital discharge from in-hospital cardiac arrest with audio feedback on compression depth and recoil.
Monitoring physiologic parameters such as arterial blood pressure or ETCO2 may optimize CPR quality.
Targeting compressions to an ETCO2 value of at least 10 mm Hg, and ideally 20 mm Hg or greater, may be useful as a marker of CPR quality.
The usefulness of double sequential defibrillation for refractory shockable rhythm has not been established.
Based on current evidence, it is not known whether double sequential defibrillation is beneficial.
Providers should first attempt establishing IV access for drug administration in cardiac arrest.
Although IV access is preferred, for situations in which IV access is difficult or not feasible, IO access is a reasonable option.
Post-cardiac arrest care may include: coronary angiography, targeted temperature management, seizure management, ventilatory management, and Glucose control.
To be reliable, neuroprognostication should be performed no sooner than 72 hours after return to normothermia, and prognostic decisions should be based on multiple modes of patient assessment.
Cardiac arrest survivors should have multimodal rehabilitation assessment and treatment for physical, neurologic, cardiopulmonary, and cognitive impairments before discharge from the hospital.
Cardiac arrest survivors and their caregivers should receive comprehensive, multidisciplinary discharge planning, to include medical and rehabilitative treatment recommendations and return to activity or work expectations.
Structured assessment for anxiety, depression, posttraumatic stress, and fatigue should be provided for cardiac arrest survivors and their caregivers.
The process of recovering from cardiac arrest extends long after the initial hospitalization and this process should be initiated during the initial hospitalization and continue as long as needed.
Debriefings and referral for follow up for emotional support for lay rescuers, EMS providers, and hospital-based healthcare workers after a cardiac arrest event may be beneficial.
Rescuers or healthcare workers may experience anxiety or posttraumatic stress of caring for a patient with cardiac arrest.
Team debriefings may allow a review of team performance (education, quality improvement) as well as recognition of the natural stressors associated with caring for a patient near death.
Because pregnant patients are more prone to hypoxia, oxygenation and airway management should be prioritized during resuscitation from cardiac arrest in pregnancy.
Because of potential interference with maternal resuscitation, fetal monitoring should not be undertaken during cardiac arrest in pregnancy.
Pregnant women who survive cardiac arrest should receive targeted temperature management with consideration for the status of the fetus that may remain in utero.

During targeted temperature management of the pregnant patient, it is recommended that the fetus be continuously monitored for bradycardia as a potential complication, and obstetric and neonatal consultation should be sought.

Muscle relaxants and myasthenic crisis

7/28/2023

https://youtu.be/cC0ZCkPkz6A

Myasthenia gravis and myasthenia crisis:

Myasthenia gravis (MG) is a condition causing muscle weakness due to autoantibodies targeting the nicotinic acetylcholine receptors at the neuromuscular junction.
Myasthenia crisis is a complication of myasthenia gravis characterized by worsening muscle weakness, which can lead to respiratory failure that requires intubation and mechanical ventilation.
It is important to note that myasthenic crisis can be life-threatening, but with prompt and appropriate management, most patients can recover.

The priorities of management of myasthenic crisis in the emergency department include:
1. Airway management:

Patients with myasthenic crisis may require intubation and mechanical ventilation to support their breathing.

2. Identification and treatment of triggers:

Common triggers include infection, surgery, pregnancy, childbirth, or tapering of immunosuppressive medications.

3. Immunosuppressive therapy:

Corticosteroids or intravenous immunoglobulin can help to improve symptoms and prevent future crises.

4. Monitoring and supportive care:

Patients with myasthenic crisis require close monitoring and supportive care, including electrolyte management, nutritional support, and physical therapy.

Muscle relaxants or paralytic agents in MG.

Both succinylcholine and rocuronium act on the same acetylcholine receptors affected in MG.
Succinylcholine causes continuous depolarization, while rocuronium competitively antagonizes these receptors.
However, in myasthenia gravis, the reduced number of receptors can lead to resistance to succinylcholine and increased sensitivity to rocuronium.
Avoid succinylcholine in myasthenic crisis, if possible.
Succinylcholine may fail to work due to reduced acetylcholine receptor density on muscle.
Succinylcholine may also lead to unpredictable effectiveness and prolonged duration of action.
However, if succinylcholine is the only option available, an increased dose should be considered.
Rocuronium is the preferred paralytic agent in myasthenic crisis, due to its competitive antagonism and a more predictable response in patients with myasthenia gravis.
The dose of rocuronium for myasthenia crisis should be reduced by approximately 50% compared to the usual dose.
The recommended dose is 0.3 to 0.5 milligram per kilogram based on expert consensus.

Hypertensive emergency

7/28/2023

https://youtu.be/bm7_BRt_sYQ

Hypertensive Emergency:

Hypertensive emergency is an acute, marked elevation in blood pressure that is associated with signs of target-organ damage,
which include pulmonary edema, myocardial ischemia, neurologic deficits, acute renal failure, aortic dissection, and preeclampsia or eclampsia.
Usually a mean arterial pressure of at least 135 millimeter mercury is needed to cause a hypertensive emergency.
However, this may vary considerably depending on the patient's baseline blood pressure.
The relative change in blood pressure from baseline is more important than its absolute value.
Hypertensive emergency can occur at lower mean arterial pressures in previously normotensive patients who have acute hypertension such as pregnant women with preeclampsia.
Alternatively, patients with chronic hypertension may have extremely elevated blood pressure without hypertensive emergency.
If the patient has acute worsening of organ function, such as aortic dissection, eclampsia, intracranial hemorrhage, then the blood pressure needs to be decreased aggressively.
In all other cases, the blood pressure should be lowered gradually to prevent dysfunction of the brain from low perfusion.

Intravenous anti-hypertensives can be divided into three groups:

(1) Truly titratable agents, (2) Quasi-titratable agents, (3) Bolus agents.
Examples of truly titratable agents include: Clevidipine, nitroglycerine, and esmolol.
Examples of quasi-titratable agents include: Nicardipine and diltiazem.
Examples of bolus agents include: Labetalol and metoprolol.

Pitfalls in the management of hypertension include:

1. Over-diagnosis of hypertensive emergencies in patients with alarmingly high blood pressure but without any damage to target organs. Such cases do not qualify as hypertensive emergencies.
2. Overly aggressive treatment of hypertensive emergencies, which can lead to excessively rapid and significant reductions in blood pressure.
3. Over-reliance on oral antihypertensive agents with unpredictable onset and effectiveness may pose a risk of dose-stacking.
4. Avoid intravenous hydralazine since its effects can be inconsistent and may occasionally cause a drastic drop in blood pressure.
5. Avoid intravenous metoprolol since it may cause severe bradycardia.

Special considerations in the management of hypertensive emergency include:
1. Aortic dissection.

Traditional teaching is to lower the systolic blood pressure to 100 to 120 millimeter mercury. Intravenous beta-blockers, most commonly esmolol, are first-line treatments due to their ability to lower blood pressure while avoiding reflex tachycardia and increased shear stress to the aortic wall.
Using nitroprusside to treat aortic dissection has become an infrequent practice due to its association with rapid and profound hypotension, tachyphylaxis, as well as the potential for cyanide toxicity.
Nicardipine with the addition of a beta-blocker would also be a reasonable choice.

2. Acute hemorrhagic stroke.

In acute brain hemorrhage, reduction of systolic blood pressure below 140 mmHg may improve functional outcomes.
This requires an aggressive approach with rapidly titrated intravenous anti-hypertensives, and extreme vigilance is necessary to prevent hypotension, which causes decreased cerebral perfusion pressure and adds to the ischemic insult.
Easily titratable medications with rapid onset and short duration of action, such as nicardipine, are recommended.

3. Acute ischemic stroke.

Stroke patients eligible for thrombolysis should have blood pressure controlled to systolic blood pressure below 185 millimeter mercury and diastolic blood pressure below 110 millimeter mercury.
For those not receiving thrombolytics, only levels of systolic blood pressure above 220 millimeter mercury or diastolic blood pressure above 120 millimeter mercury should be treated as hypertension in acute stroke is usually transient and may be protective.
A reasonable goal is about a 15% decrease in mean arterial pressure.

4. Preeclampsia or eclampsia.

Preeclampsia or eclampsia is a particularly troubling and difficult to manage hypertensive emergency since there are two patients to consider.
The first-line therapy is magnesium sulfate, administered as a 4 to 6 gram loading dose followed by 1 to 2 gram per hour infusion.
Care must be taken to monitor for urine output, deep tendon reflexes, and respiratory status.
If further antihypertensives are needed, beta-blockers can be used, but only to treat systolic blood pressure higher than 160 millimeter mercury.
Hydralazine was once touted as the preferred agent in pregnant patients;
however, its delayed onset of action, prolonged duration, and unpredictable hypotensive effects make it a less than ideal choice.

Regardless of the agent, the patient is likely to need close monitoring in a critical care setting.

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ACLS Pretest and Answers Part 2

ACLS Pretest and Answers Part 1

ACLS guidelines highlights

Muscle relaxants and myasthenic crisis

Hypertensive emergency

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