CRITICAL CARE EXAM 2

• Used for pulseless VT and VF
• High Energy stim - depolarizes all cardiac cells

• Elective or semi elective procedure used to convert an abnormal rhythm into a sinus rhythm
• patient is usually sedated (propofol)
• Impulse is synchronized on the R wave

• Used for cardiac arrest or suspected cardiac arrest
• pads are placed in the same location as a defib

Fully implantable, battery-operate system designed to recognize and terminate ventricular tachyarrhythmia's that can cause SCD

• Leads introduced thru the subclavian or cephalic vein
• Positioned inside the heart and superior vena cava

• 1. Pacing - Patient does not usually feel this
• 2. Cardioversion - low level shock to myocardium
• 3. High energy defib - max current to the heart

ICD can function as a pacer for a slow rhythm

Electrical artifact representing the discharge of electrical energy

Myocardial depolarization in response to a pacemaker spike

May be from not enough current or bad lead

The ability of the pacer to recognize intrinsic beats (natural beats)

Ability to set number of beats per minute

Ability to set amount of current delivered to the myocardium

• set system to recognize intrinsic beats
• "demand pacing"

• Noninvasive
• implemented fast
• low cost
• no additional training to apply
• can be done pre hospital setting or hospital

• Painful impulse for the patient
• Not for c spine injury or flail chest
• poor efficacy

• Temporary pacing lead
• Tip of the lead in contact with RV endocardium
• connected to a pulse generator

• minimal discomfort for the patient
• longer time window
• most reliable emergency pacer
• small amount of current delivered

• Skill required to place
• Fluoro required
• can not be placed during CPR
• Can be easily dislodged

• Inserted during open heart surgery
• thin wires into epicardial muscle
• ventricular leads - left chest wall
• atrial lead - right chest wall
• attached to conventional pulse generator

Used for sinus node dysfunction, A-fib and a-flutter with low ventricular response and 3rd degree/high grade 2nd degree AV block

• Physiologic AV synchrony
• No active patient participation
• Perm solution

• Surgical procedure
• battery replacements
• some environmental hazards

• I - Chamber paced
• II - Chamber sensed
• III - Response to setting
• IV - Programmability functions
• V - Antitachyarrhythmia functions

Leaflets fuse together and valves cannot fully open

Increased PA pressure and Pulmonary edema

LVH and decreased cardiac output

• Structural or functional disorder which decreased ventricles ability to fill and/or eject
• Dyspnea, fatigue, fluid retention and orthopnea

• Dull, sub-sternal discomfort
• associated with SOB, palpitation, sweating, NV
• Variants - Toothache, indigestion, jaw pain and back pain

• No specific chest pain or discomfort
• Silent Ischemia
• Women
• Diabetes
• Elderly
• Sudden or decompensated ventricular failure
• suddenly fluid overloaded and can not breathe

• Caused by plaque build up
• effort or anxiety related
• relieved by rest or nitro
• can progress to unstable

• Spontaneous
• Difficult to relieve - may require admission
• ECG - ST depression

• AKA Varient
• caused by spasms of the coronary artery
• Tx - calcium channel blockers
• rare occurrence
• vasoconstrictive event

• Cardiac Ischemia instantaneous
• Injury within 20 mins
• cell necrosis within 30 mins
• 50% wall thickness within 2 hours
• Infarct 90% complete within 6 hours

• HR < 60 bpm
• Typically anterior wall MI
• Reduces tissue perfusion
• Involved vessel - LAD

• Irregularly irregular
• chaotic firing of the heart cells in the atrium
• loss of atrial kick
• Thrombus formation may = CVA

• Most serious heart block
• AV node infarcted - no longer conducts impulse
• common in inferior wall MI
• May require emergency pacing

• Irritable ectopic focus in ventricle firing rapidly
• potentially fatal
• Awake - Amiodarone, elective cardiovert
• Pulseless - Immediate defib, ACLS

• Chaotic firing of individual heart cells in ventricle
• always fatal unless corrected

• Necrosis of septum
• Rupture of septal wall
• Tx - Sx

• Usually with anterior wall MI and mitral valve
• Necrotic rupture of papillary muscle
• server mitral regurg and pulm edema
• produces sudden and severe heart failure
• Tx- diuretics and Sx

• Weakened portion of myocardium
• Balloons outward during systole

• Thin,necrotic wall ruptures
• massive bleeding into the pericardial sac
• cardiac tamponade
• death within minutes

• Used for VF and VT
• Drug of choice

• Antiarrhythmic
• metabolized in the lover
• Toxicity - confusion and paralysis

• Helps restore BP
• VF and VT
• Potent vasoconstrictor

• Positive inotrope and chronotrope
• Beta 2 Stimulant
• restores sinus rhythm
• Used in PEA / asystole

• Catecholamine - stimulates adrenergic receptors in the heart and blood vessels
• increased CO, HR and BP
• Low dose - enhances renal function , used to increase output
• Mod Dose - acts like inotrope - increases contractility
• High Dose - acts as a vasoconstrictor = increased BP

• Catecholamine
• vasoconstriction = increases HR and CO
• mild inotrope
• Usually used in septic shock
• **Fill the tank first** Give fluid

• Primarily for symptomatic brady
• Increases HR (chronotrope)

• Normal Saline Solution
• Used to restore circulating volume
• Used to increase BP

• Balloon dilation
• guide wire advanced across lesion
• balloon inflated 15-90 seconds then deflated

• Performed after PTCA
• Placed to keep open

Physical removal of plaque from artery

• Tear in intimal layer of artery creates a flap which obstructs lumen
• immediate CP
• Mimics MI
• Tx - Stent

• Major post op complication
• Thrombus formation
• Sudden CP, ST segment elevation
• **Immediate return Cath Lab

• Narrowing of previously dilated vessel
• Occurs 30% within the first 6 months

• Localized SubQ bleeding
• Direct pressure to squish and break up hematoma

• Catheter manipulation in aorta creates bleeding into retroperitoneal space
• back pain / flank pain
• decreased BP, Increased HR, Decreased H&H, Restlessness

• Contained rupture of an arterial wall
• Bruit and pulsatile mass
• Tx - Stop or decrease anticoagulation
• compression by ultrasound guidance

• Presents with vascular problems
• Tx - anticoagulant , may need surgery

Invasive cardiac diagnostic procedure to investigate the hearts electrical system and responses to electrical stimuli and certain drugs

• Post cardiac surgery or PCI or cardiogenic shock
• Inserted via femoral artery
• **placement is essential**
• Diastole - aortic valve is close , balloon rapidly inflates, elevates aortic pressure,increases coronary artery perfusion, forces more blood through coronary artery
• Systole - Balloon deflates at start of systole , intra aortic volume is lowered, reducing aortic pressure, decreased myocardial workload and O2 consumption and increases coronary artery perfusion

• Does the work of the LV
• Flow assistance for failing heart
• Diverts blood flow around failing ventricle
• Decreases heart workload and maintains circulation

Increased O2 delivery to the myocardium by providing an alternate route for blood to perfuse an ischemic area of the heart

Alveoli

Physical movement of gases in and out

Movement of gases down pressure gradient

• Pumping or flow of blood into tissues and organs
• Adequate blood supply and CV functioning are needed
• amount of blood going to body and lungs

Supplies the diaphragm

• 1. Gas pressure and gradients
• 2. Surface area
• 3. Thickness
• 4. Length of exposure
• 5. Oxyhemoglobin dissociation curve

• Difference between the partial pressure of gases in the alveoli and pulmonary capillary blood
• CO2 comes out into the alveoli --> into the lungs to be expelled

Bicarb

• Measures the resistance that blood encounters as it enters the pulmonary vascular system
• represents RV afterload

• RV hypertrophy and dilation
• complication of increased PVR
• too difficult for the RV to push blood into the lungs during systole
• Major cause of death in right heart failure due to congestion in its chamber

Substance that can give up ions

Substance that can accept ions

Substance that reacts with acids and bases to maintain a neutral pH

• Represents the free hydrogen ion concentration
• Reflection of balance between carbonic acid and bicarb
• increased hydrogen ion = decreased pH
• decreased hydrogen ion = increased pH

• Decreased pH = Increased RR/ depth to blow off CO2
• Increased pH = Decreased RR/ depth to retain CO2

• Decreased pH = kidney holds bicarb
• Increased pH = kidney excretes bicarb

• Key is rapid recognition of occurrence
• Medical emergency
• **Doesn't respond to typical asthma tx**
• Tx - O2/mechanical vent, IV steroids, Heliox

• Life threatening
• Cardiopulmonary system is unable to make demand

• Failure of oxygenation
• Tachycardia
• Tachypnea
• Possible dysrhythmias
• Confusion/change in mental status

• Failure of ventilation
• inadequate CO2 removal
• Tremors
• any neurologic event
• lethargic
• headache
• flushed skin
• increased CO2 = vasodilation

• Complication of a disease process
• caused by indirect or direct pulmonary injury
• sepsis is most common cause

*Injury to alveoli epithelium - allows fluid to flood into alveoli due to injury

• Diffuse epithelial injury with inc'd permeability of the alveolar-capillary membrane
• Permeability permits fluid, protein and blood cells to enter alveoli of the lung
• Accumulation of fluids to alveolar cell damage, surfactant inactivation and formation of a hyaline membrane that inhibits gas exchange
• Results = non-cardiogenic pulmonary edema (alveolar flooding)

• **PaO2/FIO2
• Normal 300-500
• Mild 200-300
• Moderate 100-200
• Severe < 100

• 1. Exudative Phase - commencing within 24H
• Type 1 pneumocytes destroyed (responsible for gas exchange)
• Diffuse alveolar damage
• Diffuse microvascular damage
• Neutrophil infiltration
• 2. Fibroproliferative Phase - for 3-7 days
• lung repair period varies
• type 2 pneumocytes hyperplasia (responsible for surfactant )
• Lung remodeling

• Not very effective
• Corticosteroids - Reduce the inflammation
• Nitric Oxide - increased vasodilation = improved perfusion, ventilation and oxygenation
• surfactant

• Blockage in pulmonary arterial system
• Disrupts blood flow to an area in the lungs
• can be thrombotic or nonthrombotic