Cardiovascular 

Acute Coronary Syndrome

(Myocardial infarction including NSTE-ACS/NSTEMI and STEMI)

65 y/o M with h/o HTN, CAD, HLD, previous MI, CKD, DM, smoking presents with acute onset chest pain. Reports two episodes of chest and L arm pain similar to previous angina episodes within the past 24 hours. Pain severity acutely increased prior to presentation. Medications include ASA with last use within previous 7 days. Records show coronary artery stenosis ≥ 50%. Family h/o MI-related death 1st degree M relative <55 y/o and 1st degree female relative <65 y/o. Hypotension, diaphoresis, pulmonary crackles, and transient mitral regurgitation on exam. Pain not reproducible with palpation.

• TIMI risk score

  • ≥ 2 indicated need for urgent evaluation

  • ≥ 4 indicates high likelihood of CAD as the cause of chest pain (LR 11.2)

• Stat troponins values > 0.150; obtain repeat troponins at 3 and 6 hours s/p initial draw

• Stat EKG obtained within 10 minutes of presentation shows NSTE-ACS vs. STEMI (see below for specific treatment)

Treatment

• Initial therapy

  • Aspirin: Chew non-enteric coated 325 mg at symptom onset

  • Nitroglycerin 0.4 mg sublingually q5 minutes for up to 3 doses as BP allows

  • SPO2 <90%: Start oxygen 4L by NC

  • Heparin 60 u/kg IV bolus (max 4,000 u) followed by 12 u/kg/hr infusion (max 1,000 u/hr) to maintain aPTT 1.5-2.0 until revascularization (see STEMI) or 48 h s/p symptom onset

  • Consider morphine 4-8 mg IV q15 min for refractory chest pain

• Treatment based on EKG findings

  • NSTE-ACS

    • ST depression in contiguous leads ≥ 0.5 mm, T wave inversion, and new onset Q waves

    • Able to take aspirin; administer clopidogrel 600 mg loading dose

  • STEMI: ST elevation and new onset L bundle branch block (see notes for details)

    • Percutaneous coronary intervention (PCI) capable facility: Complete PCI within 12 hours of symptoms onset and administer clopidogrel 600 mg s/p procedure

    • PCI not available and pt < 75 y/o with CrCl > 30: Transfer to a capable facility (preferred) or administer clopidogrel 300 mg and fibrinolytic therapy (tPa)

• Additional therapy

  • Start carvedilol 6.25 mg BID and titrate as tolerated

  • Start lisinopril 2.5 mg qd within 24 hours of symptoms onset; titrate to 10 mg qd

  • Continue clopidogrel 75 mg qd maintenance therapy x12 months

  • Start atorvastatin 80 mg qd

• Establish outpatient appointment with cardiologist upon discharge

Notes

• Epidemiology

  • CAD risk factors include HTN, HLD, DM, current smoking, and family h/o CAD

  • Average age at first MI is 65 years

  • Most predictive s/sx include abnormal stress test, h/o peripheral arterial disease, diaphoresis, acute hypotension, and EKG changes

• Myocardial infarction terminology

  • MI definition: Ischemia-induced cardiac muscle damage resulting in elevated troponins (>3x ULN) and one of the following

    • Signs or symptoms of ischemia

    • New, significant EKG changes (see below)

    • New cardiac wall motion abnormality on echo

  • Ischemia subtypes

    • Type 1: Thrombotic occlusion of a vessel

    • Type 2: Myocardial oxygen demand exceeds oxygen supply

  • Non-ST elevation myocardial infarction (NSTEMI)

    • Term no longer used by the American College of Cardiology

    • Now grouped with unstable angina and known as non-ST elevation acute coronary syndrome (NSTE-ACS)

• Troponins >3x ULN are considered significant; this value varies locally and >0.150 is used an example above because it applies to this author’s local institution

• EKG changes

  • ST elevation: Anatomically contiguous lead changes that meet any of the following criteria:

    • ≥ 2 mm in men or ≥ 1.5 mm in women for leads V2-3

    • ≥ 1 mm for leads V1, V4-6, I-III, AVL, AVF

  • New onset L bundle branch block in the setting of acutely elevated troponins is considered an MI (STEMI) equivalent

• Absolute contraindications to fibrinolytic therapy (e.g. tPa)

  • Blood pressure

    • Systolic BP > 180 mmHg, diastolic BP > 100 mmHg

    • R vs. L arm pressure > 15 mmHg

  • CNS

    • Closed head trauma within previous 3 months

    • Any history of intracranial bleeding

    • Ischemic stroke > 3 hours or within previous 3 months

    • Structural CNS disease (vascular malformation, neoplasm, etc.)

  • Pregnancy

  • ESRD

  • Metastatic malignancy

  • Surgery within the past 4 weeks

Thrombolysis in MI Risk Score

1 point for each:

• Age>64

• 3+ CAD risk factors

• Known CAD with >50% stenosis

• Aspirin use within past 7 days

• 2+ anginal episodes within preceding 24 hours

• Elevated troponin I

• ST segment deviation >0.5mm on admission ECG

Interpretation

• Low risk (0-2): Stress test

• Intermediate (3-4) to high (5-7) risk: Coronary angiography within 24 hours

• Immediate coronary angiography for hemodynamic instability, heart failure/new MR, recurrent chest pain, ventricular arrhythmia

Atrial Fibrillation with Rapid Ventricular Response

Elderly pt with h/o psychosis, depression presents s/p cardiac surgery with palpitations and s/sx suspicious for HF vs. MI vs. stroke. Reports fatigue, chest pain, syncope, dizziness, dyspnea, and orthopnea. Medical history includes coronary artery disease, structural heart disease, heart failure, collagen vascular disease, pulmonary disease, sleep apnea, thyroid disease, and ongoing substance abuse. Medications include OTC diet pills, albuterol, lithium, and QTc-prolonging agents. Hypothermia, tachycardia, JVD, pulmonary crackles, systolic heart murmur, S3 gallop, irregular peripheral pulses on exam.

• Labs

  • Obtain CBC, CMP, TSH

  • Consider urine drug screen

• EKG: Rapid, irregularly irregular rate with absent P-waves, narrow Q-waves

• New onset with no previous echocardiogram: Obtain echocardiogram to evaluate for valvular A-Fib

• Rate control

  1. Patient stable: Maintenance rate control with goal HR < 110 bpm at rest

     • SBP > 100 mmHg: Metoprolol tartrate 25 mg BID (MDD 100 mg BID)

     • SBP < 100 mmHg: Digoxin 0.125 mg daily (MDD 0.25 mg daily)

  2. Acute hypotension, altered mental status, chest discomfort or HR consistently > 120 BPM:

     • SBP > 100 mmHg: Cardizem 0.25 mg/kg bolus over 2.5 min then 10 mg/hr infusion for up to 24 hr

     • SBP < 100 mmHg and/or HFrEF: Digoxin 0.25 mg; re-dose q6h to achieve HR < 110 bpm

  3. Rate control ineffective

     • Obtain cardiac consult

     • Consider cardioversion if AFib duration < 48h or pt hemodynamically unstable

• Stroke prevention

  • CHADSVASC > 1, HASBLED < 3, age > 80 years, weight > 60 kg, Cr < 1.5, and no valvular AFib on echocardiogram: Start abixaban (Eliquis) 5mg BID

  • Consider referral for

    • Cardiac and/or left atrial appendage ablation

    • Watchman device placement

    • Pacemaker placement

• Refer for sleep apnea testing as outpatient

• Counseling

  • Pt counseled that spontaneous A-Fib generally resolves within 7 days

  • Pt advised to limit alcohol consumption to < 1 drink per day

Notes

Considerations

• QTc-prolonging drugs

  • Increase A-Fib risk

  • Commonly associated agents include anti-arrhythmics, antidepressants, anti-psychotics, fluoroquinolones, macrolides, and antifungals

• Heart rate

  • A-Fib is a tachycardia with HR generally between 90-170 BPM; consider sick sinus syndrome in bradycardic patients

  • A-Fib with RVR (rapid ventricular response) rarely causes clinical instability unless HR > 150 bpm

Rate control

• Rate control equivalent to rhythm control per AFFIRM trial (N Eng J Med. 2002;347(23):1825-1833)

• Lenient control (HR < 110) per RACE II trial (N Eng J Med. 2010;362(15):1363-1373)

• Rate control advanced organizers:

  • ABCD: A-Fib agents include Beta-blockers, Cardizem, Digoxin

  • Maintenance agents: Beta-blocker (metoprolol) or digoxin

  • Acute agents: Cardizem or digoxin

  • Rule of '0.25' for acute dosing, i.e. Cardizem 0.25 mg/kg bolus over 2.5 min or digoxin 0.25 mg

• Metoprolol succinate

  • Long acting oral formulation

  • Provide most effective heart rate control at rest and during exercise

  • Contraindications: Systolic pressure <100 mmHg, h/o Wolff-Parkinson-White syndrome

• Diltiazem (Cardizem): Often used off-label for maintenance dosing

  • Initial dose: Immediate release 60 mg BID

  • Maximum dose 120mg TID

  • Contraindication: Systolic <100 mmHg

• Digoxin: Used off-label for maintenance dosing in patients with hypotension

Rhythm control

• For stable patients with A-Fib duration >48h, one of the following is required before cardioversion:

  • Anti-coagulation for 4 weeks

  • TEE to rule out presence of atrial thrombus

• Unstable patients

  • Amiodarone IV: 150 mg over 10 minutes, then 1 mg/minute x6 hours, then 0.5 mg/minute x18 hours, then oral maintenance dosing

  • Synchronized electrical cardioversion: 120-200J biphasic or 200 J monophasic

Stroke

• Stroke risk

  • 5 times greater in patients with AFib

  • Further elevated if AFib is caused by valvular disease

    • Valvular disease includes mechanical heart valves, rheumatic heart disease/mitral stenosis, decompensated heart failure due to valve dysfunction

    • Use warfarin (Coumadin) to anticoagulate these patients

• Stroke prevention

  • CHADSVASC: Aspirin if equal to 1, anticoagulation for score of 2 or greater

  • HASBLED determines bleeding risk; score of 3 or greater indicates high risk

  • Apixaban (Eliquis)

    • May not be covered by insurance

    • Not approved for use in pregnancy, dialysis, or valvular A-Fib

  • Watchman device occludes LA appendage and reduces embolization risk

CHADS-VASc

Used to calculate stroke risk in patients with atrial fibrillation.

• CHF: +1

• HTN: +1

• Age: 65-74 [+1], >75 [+2]

• DM: +1

• Stroke: +2

• Vascular disease: +1

• Sex F: +1

HASBLED

1 point for each of the following:

• Hypertension >160mmHg systolic

• Abnormal renal function, i.e.

  • Dialysis

  • Transplant

  • Cr >2.26 mg/dL or >200 µmol/L

• Abnormal liver function, i.e.

  • Cirrhosis

  • Bilirubin >2x normal + AST, ALT, or AP >3x normal

• Stroke: Prior history of stroke

• Bleeding: Prior Major Bleeding or Predisposition to Bleeding

• Labile INR, i.e.

  • Elevated INR

  • INR within therapeutic Range < 60% of the time

• Elderly: Age > 65 years

• Drugs: Antiplatelet agents, NSAIDs, ≥ 8 drinks/week"

Additional Arrhythmias

AV Block

• First degree

• Second degree

  • Mobitz 1 → Treat underlying condition, e.g.

    • Ischemia affecting AV node

    • Hypothyroidism

  • Mobitz 2 → Pacemaker

• Third degree heart block → Pacemaker

Sinus Node Disease (Sick Sinus Syndrome)

• Risk factors: Age > 60 years, CAD, hypothyroidism, medications

• May present with persistent tachycardia, persistent bradycardia, or tachy-brady syndrome

• Symptomatic patients: Refer for pacemaker placement

Torsades de Pointes

• Polymorphic ventricular tachycardia

• Risk factor: Electrolyte imbalance (e.g. hypokalemia), medications

• Often progresses to ventricular fibrillation

• Treat with magnesium

Heart Failure

Elderly patient with history of hypertension, coronary artery disease, valvular heart disease, atrial fibrillation, and diabetes mellitus type 2 presents with dyspnea on exertion, fatigue. Reports new onset orthopnea, nocturnal cough. Heart rate > 120 bpm, jugular venous distention, hepatojugular reflux, bibasilar crackles, S3 gallop, 2+ pitting lower extremity edema on exam.

• Patient meets Framingham heart failure diagnostic criteria

• Labs

  • NTpBNP > 400 pg/mL

  • Obtain CBC, ferritin, TIBC, CMP

  • Consider lipid profile, TSH, U/A, HbA1c

• Imaging

  • Atrial fibrillation on EKG

  • CXR shows cardiomegaly, venous congestion, interstitial edema with Kerley B lines

  • Echocardiogram shows (one of the following patterns):

    • Preserved ejection fraction: LVEF > 50%, elevated LA pressure, impaired LV relaxation, decreased compliance, and E/A reversal

    • Reduced ejection: LVEF < 50%

• Treatment

  • Patient counseled about weight loss, dietary sodium reduction, smoking cessation

  • ACE inhibitor: Lisinopril

    • Preserved ejection fraction: Start 5 mg daily and increase by 10 mg every two weeks to target dose of 40 mg daily

    • Reduced ejection fraction: Start 10 mg daily and titrate to 20 mg daily as needed for blood pressure control

  • Additional medications

    • EF < 40%: Metoprolol succinate 50 mg daily

    • Symptomatic (e.g. dyspnea): Chlorthalidone 25 mg daily

    • Start statin if patient qualifies

  • Atrial fibrillation at any EF

    • Aspirin 81 mg + anticoagulation per CHA2DS2-VAsc

    • Metoprolol succinate 50 mg daily

• Heart failure with reduced ejection fraction (HFrEF)

  • Hypervolemia

    • Fluid restrict to 1.5 L daily to correct hypervolemia, hyponatremia

    • Hypervolemia refractory to fluid restriction: Stop chlorthalidone, start bumetanide 1 mg daily and titrate to 2 mg daily

  • Ferritin < 100 ng/mol

    • Administer 1000 mg IV iron ferric carboxymaltose bolus

    • Schedule follow-up at 6, 12, 24, and 36 weeks to monitor anemia

  • LVEF < 30% with GFR > 30 mL/min

    • Start spironolactone 12.5 mg daily and double dose every 4 weeks to 50 mg daily while monitoring for hyperkalemia

    • Persistent symptoms despite spironolactone: Consider digoxin 0.125 mg daily

  • LVEF < 30% and fatigue, palpitation, dyspnea, or anginal pain provoked by moderate exertion: Consult cardiology for defibrillator placement

• Additional considerations

  • Consider transition of ACE to Entresto (valsartan + sacubitril) in patients with HFrEF class II-III to improve outcomes

  • African American with uncontrolled HTN on ACE/beta-blocker: Consider isosorbide dinitrate/hydralazine (Bidil) 1 tablet TID

  • Angina/chest pain present: Obtain stress test (may require catheterization)

• Follow up as outpatient within 7 days after hospital discharge to reduce readmission rate

Notes

Non-hypertensive Causes of Heart Failure

• Cardiac: Pericardial constriction, primary valvular disease, atrial myxoma

• Infiltrative disorders: Amyloidosis, sarcoidosis

• Storage disorders: Hemochromatosis

NYHA Stages of Heart Failure

1. No limitation of physical activity

2. Light limitation of physical activity: Ordinary activity causes fatigue, palpitations, or dyspnea

3. Marked limitation: Less than ordinary activity causes fatigue, palpitations, or dyspnea

4. Unable to engage in physical activity without symptoms, or symptoms that occur at rest

HFpEF

• Definition: EF > 50% with s/sx of HF (diagnosis of exclusion)

• Pathophysiology

  • Reduced ventricular compliance reduces ventricular filling during diastole

  • Most commonly associated with LV hypertrophy

• Treatment

  • Controlling hypertension improves prognosis

  • Beta-blockers reduce heart rate and improve ventricular filling

HFrEF

• Medications that improve mortality

  • Beta-blockers

    • Approved agents: Metoprolol succinate, carvedilol (Coreg), bisoprolol

    • Start in all patients when euvolemic and stable

    • Contraindications: Hemodynamic instability, bradycardia, severe asthma

  • Aldosterone antagonists (e.g. eplerenone, spironolactone) in patients with EF < 35% and symptomatic HF (survival advantage observed within 30 days)

  • Vasodilators: Hydralazine, isosorbide dinitrate

• Additional medications

  • Diuretics and digoxin: Improve symptoms, but do not decrease mortality

  • Amlodipine may help control blood pressure, but does affect HF outcomes

  • Verapamil: Negative inotropic effect worsens heart failure

• Statins do not improve outcomes for patients who do not otherwise meet criteria for lipid-lowering therapy, see CORONA, GISSI-HF trials

BNP

• Volume expansion → increased ventricular pressure → ventricular dysfunction → BNP release

• Renally cleared, i.e. ↓ Cr clearance = ↑ BNP

• BNP > 400

  • LR = 19 for heart failure

  • Does not necessarily indicate acute exacerbation

• HF exacerbation: BNP at admission is correlated with inpatient mortality

Dilated Cardiomyopathy

45 y/o pt with h/o autoimmune disease, DM, Hep C, HIV, alcoholism, malignancy s/p radiation/chemotherapy presents with SOB. Pt has noted new onset palpitations and was recently treated for DVT. Reports family h/o dilated cardiomyopathy. Tachycardia, lower extremity edema on exam.

• Obtain CMP

• EKG shows T wave changes, septal Q waves, bundle branch block

• Echo shows ventricular enlargement with normal left ventricular wall thickness and reduced ejection fraction

• Reduced ejection fraction: Start lisinopril 5 mg qd, metoprolol succinate 25mg qd

• NYHA class 2 or greater with reduced ejection fraction and GFR>30: Start Entresto (sacubitril/valsartan) 24/26 mg s/p 36 hour washout period for previous ACE

Notes

• Approximately 30% of cases are familial

• ACEs/ARBs provide significant mortality benefit in patients with reduced ejection fraction

Hypertrophic Cardiomyopathy

Pt with h/o dyspnea on exertion presents with recurrent, acute chest pain. Chest pain generally occurs during meals or exercise and is more common during summer months. Family h/o sudden, unexplained cardiac death. Systolic murmur with increased intensity during Valsalva on exam.

• EKG shows left ventricular hypertrophy (LVH), Q-waves

• Echocardiogram shows LVH with decreased chamber volume

• LVEF < 50%

  • Refer to heart failure (HFrEF) treatment guidelines

  • Plus anginal symptoms: Start nadolol 40 mg qd

• Refer for implantable cardioverter-defibrillator (ICD) placement for any of the following:

  • H/o sudden death in 1st degree relative

  • Ventricular wall thickness > 30mm

  • Sustained ventricular tachycardia and/or cardiac arrest

• Pt counseled that alcohol septal ablation or surgical myomectomy may be necessary for end-stage heart failure

Notes

• Prevalence 1:500

• Chest pain worse with dehydration

• Valsalva reduces preload/filling, resulting in less blood in the heart

Takotsubo Cardiomyopathy

Postmenopausal female presents with acute-onset chest pain. Reports recent dyspnea, syncope, emotional/physiologic stressors. No h/o myocarditis, pheochromocytoma, cocaine use. Tachycardia, hypotension, respiratory distress, cold extremities on exam.

• Labs

  • Initial troponin >0.02

  • Obtain troponin x3, pro-BNP; consider UDS to r/o cocaine use

  • Strict I&O's; monitor for oliguria

• Imaging

  • EKG shows ST-segment elevation and/or T wave inversion

  • Echocardiogram shows LV dysfunction and LV apical ballooning; no evidence of obstructive coronary disease

  • Angiography shows no evidence of acute plaque rupture

• Treatment

  • Manage acute cardiogenic shock per ACS guidelines

  • Once stable, start lisinopril 10 mg daily, metoprolol succinate 25 mg daily, HCTZ 25 mg daily

  • Loss of LV wall motion on echocardiogram: Start abixaban 5mg BID x4 months for thrombus ppx

• Pt counseled that symptoms typically resolve within 1 month

Notes

• Prevalence

  • Affects 1 in every 5,000 hospitalized patients

  • Responsible for 1 in every 75 cases of troponin-positive ACS

Aortic Dissection and Aneurysm

Aortic Dissection

65 y/o M with h/o HTN present with acute back pain. Pain is inter-scapular and tearing in nature. Reports syncopal episode s/p pain onset. Asymmetric blood pressure and upper extremity pulses on exam.

• CT with contrast shows dissection

• Contraindication to IV contrast: Obtain transthoracic (TTE) and/or transesophageal echo

• Treatment

  • Start IV esmolol to reduce LV ejection velocity

  • Start IV nitroprusside to lower systolic blood pressure to 90-110 mmHg

Note: Syncope occurs in 9% of patients with aortic dissection

Abdominal Aortic Aneurysm (AAA) Screening

• Etiology and Epidemiology

  • Due to atherosclerosis

  • Affects 2-5% of patients > 65

  • Approximately 5:1 male:female predominance

• USPSTF recommends one-time screening for AAA with ultrasound in men ages 65-75 who have ever smoked (i.e. >100 cigarettes in a lifetime)

• Management based on diameter:

  • AAA < 5.5 cm in men: Repair for growth > 0.5 cm in 6 months or > 1 cm per year

    • Aneurysm 3.0 to 4.0 cm: Ultrasound yearly

    • Aneurysm 4.0 to 5.5 cm: Ultrasound every 6 months for one year and then yearly if no growth

  • AAA > 5.5 cm in men or > 5.0 cm in women:

    • Life expectancy > 2 years and a surgical candidate: Refer for surgical endovascular repair

    • Life expectancy < 2 years: Do not repair

Abdominal Aortic Aneurysm Rupture

65 y/o M with a h/o HTN, AAA, and Marfan’s syndrome presents with acute onset abdominal pain radiating to the flank and groin. Reports associated vomiting and syncope. Hypotension on exam with a pulsatile abdominal mass.

• STAT non-contrast abdominal CT shows AAA rupture

• Obtain STAT vascular surgery consult

• Patient’s family counseled that condition is associated with 80% mortality rate

Peripheral Arterial Disease

Pt age > 65 years h/o HTN, HLD, CVA, heart failure, chronic kidney disease, DM, smoking presents with calf pain/cramping during activity. Pain resolves after approximately 10 minutes rest. Diminished pulses, pallor, hair loss, and non-healing gangrenous wound on lower extremities; ankle-brachial index 1.3 < ABI < 0.9.

• Obtain CBC, CMP, BNP

• Lipid panel shows HDL < 50 mg/dL

• EKG shows Q waves and ST segment changes

• Treatment

  • Start supervised exercise therapy program

  • Start aspirin 81 mg qd, ramipril 2.5 mg qd x 1 week and then 5 mg qd, atorvastatin 80 mg qd

  • Continued pain s/p supervised exercise therapy and no h/o heart failure: Start cilostazol 100 mb BID; pt counseled about risk for dizziness, GI distress due to vasodilatory effects

• Consults/Referral

  • Refer for abdominal aortic aneurysm (AAA) screening

  • Refer for surgical revascularization for cases of

    • Lifestyle limiting claudication with insufficient response to exercise/medical therapy

    • Ischemic rest pain x 2 weeks

  • Admit to hospital for emergent vascular surgery within 4 to 6 hours in cases of limb-threatening ischemia as indicated by painful, pale/dusky colored and cold extremity with absent pulses, motor weakness, sensory impairment

• Pt advised to stop smoking and offered smoking cessation therapy

Notes

• Epidemiology

  • Affects 50% of patients age > 85

  • Only 10% of PAD patients experience claudication

• Diagnosis

  • Ischemic rest pain generally occurs when feet are elevated and resolves in the dependent position, e.g. sleeping pt must hang feet over side of bed

  • Ankle-brachial index (5-8 MHz vascular probe not 2-3 MHz fetal probe)

    • 94-97% sensitivity for detecting angiographically significant stenosis

    • Values > 1.3 suggest non-compressibility; use toe index with > 0.7 considered normal

  • HDL < 40 and 50 mg/dL in males/females receptively is associated with increased risk of death

  • Consider BNP to r/o heart failure before starting cilostazol

• Treatment

  • Dual antiplatelet therapy is generally not more effective than aspirin

  • Heart Outcomes Prevention Study: ACE (ramipril) or ARB (telmisartan) reduced MI, stroke, and mortality in patients with PAD and no h/o heart failure

  • Statin NNT ~ 5 to reduce risk of long-term adverse outcome

  • Supervised exercise therapy can often be performed at a physical therapy center; otherwise, pt should walk until pain onset and then rest until pain subsides

  • Cilostazol contraindicated in heart failure

Undifferentiated shock

Pt with h/o respiratory compromise, arterial occlusion presents with acute onset hemodynamic instability. Tachycardia, tachypnea, hypotension, confusion/delirium, increased WOB, dry mucous membranes, JVD, arrhythmia, cyanosis/mottling on exam. Systolic BP <90 with MAP <65; urine output <0.5 mL/kg/hr.

• Labs

  • Obtain CBC with diff, CMP, ABG, serum lactate

  • Obtain troponin, CKMB, BNP, creatinine kinase

  • Obtain U/A, blood cultures, sputum cultures

  • Obtain type and PT/PTT/INR, D-dimer

  • Consider urine drug screen

• Triage

  • ABG shows high anion gap metabolic acidosis, serum lactate >2

  • Serum lactic acid >4: Transfer pt to MICU

• Imaging

  • Obtain EKG, CXR, U/S of IVC

  • Start continuous cardiac telemetry

  • CT if concern for trauma and/or intracranial hemorrhage

• Stabilize respiratory status

  • Titrate supplemental O2 to maintain SPO2 > 92%: Administer oxygen via NC 6L/min; if insufficient proceed to HFNC 20L/min, then BiPAP 12/5, and finally intubation

  • GCS<8 or marked respiratory distress/hemodynamic instability with no suspected tension pneumothorax: Administer ketamine 1.5 mg/kg IV, rocuronium 1.5 mg/kg IV and intubate

  • Specific interventions

    • Anaphylaxis: IV epinephrine

    • Tension pneumothorax: Chest tube

    • Massive pulmonary embolus: Thrombolytic therapy

• Circulatory

  • Establish IV access; administer 1L LR bolus followed by maintenance fluid

  • If peripheral access cannot be obtained and/or vasopressors indicated, place central line

  • MAP <65 s/p fluid resuscitation; start noradrenaline (Levophed) at 0.2 mcg/kg/hr and titrate to MAP >65

  • Specific interventions

    • Stroke: Evaluate for tPA; consult neurology

    • Arrhythmia with hemodynamic decompensation: ACLS protocols

    • Myocardial infarction: Coronary revascularization

    • Cardiac tamponade: Pericardiocentesis

• Sepsis

  • Initiate broad-spectrum antibiotics

  • Calculate Q-SOFA score

Notes

• MAP > 60 required to maintain cerebral perfusion

• Serum lactate

  • >2 indicates likely shock

  • >4 is "not for the floor" as it predicts increased mortality independent of organ hypoperfusion

• Q-SOFA score

  • One point for each of the following

    • GCS <15

    • Respiratory rate >21

    • SBP <101

  • Score of 2 or greater indicates high risk of poor outcome in patients with suspected infection, i.e. 3 to 14 times higher risk of in-hospital mortality

Cardiogenic shock

Pt with h/o severe HTN, DM, CAD, MI, HFrEF, dilated cardiomyopathy, aortic stenosis, stable abdominal aortic aneurysm presents with arrythmia s/p ingestion of beta-blockers during suicide attempt. Reports dyspnea, acute on chronic chest pain, syncope, recent chest trauma, and alcohol/cocaine abuse. Systolic BP < 90 mmHg, bradycardia, tachypnea, JVD, bibasilar pulmonary crackles, mid-systolic ejection murmur at R upper sternal border, cool extremities, confusion on exam.

• Obtain CBC, CMP, serial troponin, ABG, lactic acid, PT/PTT/INR

• Obtain EtOH level, urine drug screen

• Strict I&O’s and monitoring for oliguria

• EKG shows myocardial ischemia: Evaluate for acute coronary syndrome

• CXR shows tension pneumothorax and new onset pulmonary congestion

• CTA shows pulmonary embolism

• Obtain echocardiography; evaluated for acute myopericarditis, takotsubo cardiomyopathy, HFrEF, pericardial tamponade, ascending aortic dissection

• Treatment based on underlying condition

Notes

• May be due to the heart itself (vessel/muscle/valve), arrhythmia (tachy/brady), or obstruction

• Heart defects

  • Vessel infarction → ischemia → acute coronary syndrome

  • Muscle

    • Dilated cardiomyopathy (consider in pt with h/o alcohol abuse)

    • Takotsubo cardiomyopathy

    • Acute myopericarditis

    • Cardiac contusion

  • Valvular insufficiency: Severe valvular stenosis, chordae tendinae rupture, valvular stenosis, ventricular septal wall defect/rupture

• Arrhythmia: Treat per ACLS guidelines

• Obstruction

  • Decreased cardiac return

    • Vena cava syndrome

    • Massive pulmonary embolism

  • Cardiac compression

    • Tension pneumothorax

    • Pericardial tamponade

  • Outflow obstruction: Ascending aortic aneurysm

Distributive shock

Pt with h/o anaphylactic shock, hypothyroidism, hypoadrenalism presents with spinal trauma. Recently diagnosed with group A strep pneumonia and suffered bee sting prior to admission. Fever, hypotension, confusion/delirium, facial edema, dry mucous membranes, inspiratory stridor, hives, skin warmth below level of spinal injury, localized area of skin necrosis with abscess on exam. No LE edema, JVD noted. Systolic BP < 90 with MAP < 65, urine output < 0.5 mL/kg/hr.

• Diagnostic approach

  • Obtain q 1 hour vital signs until stable

  • Obtain CBC with differential, CMP, ABG, type and cross

  • Obtain serum lactate now, at 2 hours, and then q6h until stable

  • Obtain blood culture, sputum culture, U/A with culture, wound culture

  • Obtain troponin, CKMB, BNP, creatinine kinase

  • U/S shows IVC > 1.5 cm, i.e. adequate blood volume

• Initial treatment

  • Secure airway, correct hypoxemia (nasal cannula → high flow nasal cannula → BiPap)

  • Transfuse for hemoglobin < 7 g/dL

  • Place central line if peripheral access cannot be obtained and/or vasopressors indicated

    • Administer 1L LR bolus followed by maintenance fluid (goal = 30 mL/kg over 3 hours) before starting vasopressors

    • MAP < 65 s/p fluid resuscitation: Start noradrenaline (Levophed) at 0.2 mcg/kg/hr and titrate to MAP > 65

• Anaphylactic shock

  • Administer 0.3 mg epinephrine 1:1000 injected in outer thigh q 10 min

  • Administer diphenhydramine 50 mg IV, ranitidine 50 mg IV, methylprednisolone 1 mg/kg IV

  • Administer albuterol 2.5 mg nebulized solution

• Septic shock

  • Initial CBC shows bandemia

  • Obtain blood culture from two distinct venipuncture site and any indwelling devices

  • Start linezolid (Zyvox) IV 600 mg BID, Zosyn 3.375 g IV q8h

  • Suspected infection source

    • CNS (e.g. meningitis): CSF cell count, protein, glucose, Gram stain, and culture

    • Respiratory tract: Start chest physiotherapy, suctioning for pneumonia

    • Intra-abdominal: Obtain abdominal CT +/- stool culture

    • Urinary tract: Change catheter and consult urology if urinary tract obstruction suspected

    • Skin and soft tissue: Debride necrotic tissue, drain abscess and/or effusion

    • Bone: Obtain MRI +/- bone culture

    • Indwelling device: Discontinue or replace access site

• Myxedema coma/adrenal crisis

  • Obtain TSH, free T4 serum cortisol, ACTH, aldosterone, renin

  • Administer levothyroxine 300 mcg IV, followed by 75 mcg qd

  • Administer triiodothyronine 10 mcg intravenously, followed by 5 mcg q8h

  • Administer hydrocortisone 100 mg IV q8h until adrenal insufficiency excluded

  • Consult endocrine

• Neurogenic shock

  • Obtain CT at level of traumatic spinal cord injury (TSCI)

  • Presenting within 8 hours of isolated, non-penetrating TSCI: Consider methylprednisolone 30 mg/kg IV bolus followed by 5.4 mg/kg infusion x 23 hours

  • Consult neurology

Notes

• Potential distributive shock etiologies

  • Infectious

    • Septic shock (e.g. pneumonia)

    • Group A streptococcal infection (e.g. skin necrosis)

  • Non-infectious

    • Anaphylactic shock (characterized by allergen exposure followed by facial edema, inspiratory stridor, hives)

    • Endocrine etiologies including adrenal crisis, myxedema coma due to hypothyroidism

    • Neurogenic shock

• Antibiotics: Zyvox, Zosyn, aZithromycin for pan coverage

  • Linezolid: Gram positive coverage including MRSA (neurotoxicity risk limits use to < 2 weeks)

  • Zosyn

    • Covers anaerobes and gram negative organisms including pseudomonas

    • Does NOT cover Legionella

    • Does NOT cover organisms with inducible beta-lactamase activity that is chromosomally mediated, i.e. ESCHAPPM (Enterobacter, Serratia, Citrobacter freundii, Hafnia, Aeromonas, Proteus vulgaris, Providencia, Morgananii)

  • Azithromycin: Covers Legionella

  • Moxifloxacin: Covers Legionella and ESCHAPPM organisms

  • Antifungal: Mycofungin 100mg IV qd if disseminated fungal infection is present

Hypovolemic shock

Pt with h/o pancreatitis, intestinal obstruction, polyuria presents with blood loss s/p crush injury. Reports N/V, diarrhea s/p completing a marathon. Orthostatic hypotension, tachycardia, acute weight loss, dry mucous membranes, bleeding cool/mottled extremities, delayed capillary refill, weakness, crush injury, and agitation/confusion on exam.

• Obtain CBC, CMP, serial troponin, ABG, lactic acid, PT/PTT/INR

• Obtain urine sodium, creatinine, osmolality

• Urine sodium <20 mEq/L, FENA <0.2, urine osmolality >450 mOsmol/kg

• Strict I&O’s; monitor for oliguria

• Bedside U/S shows IVC diameter <1.5cm

• Establish access using two large-bore IVs

• Administer 2L LR bolus; give additional boluses until MAP>65

• Massive blood loss, hemoglobin <7: Adminster PRBCs

Notes

• Third-spacing may occur due to intestinal obstruction, crush injury, fracture, and acute pancreatitis

• Low urine sodium and elevated urine osmolality strongly suggest tissue hypoperfusion; exceptions include

• Patients with polyuria due to hypoaldosteronism, diuretic abuse, etc.

• Metabolic alkalosis due to vomiting

• FENA = ([Plasma creatinine × urinary sodium] / [plasma sodium × urinary creatinine]) × 100

• Do NOT administer vasopressors