1. What lead is best used to detect inferior wall ischemia and arrhythmias (good visualization of P-waves)?
2. V5 views what area of the heart? What percent of ischemic events can be detected in lead V5?
1. Lead II
2. anterior lateral of lft LV
1.) What is the name or the EKG triangle that demonstrates the potential electrical differences for standard limb leads?
2.) Where does the negative lead start?
3.) The heart depolarizes from Negative to positive?
- Einthoven's triangle
- Rt upper limb
1. What is a modified three lead system and what is its advantage?
1. Places RA- limb below clavicle and the LA+ lead in the V5 position. Use Lead I to visualize lateral wall ischemia if pt has a Hx.
1. 5 lead system adds what two leads?
1. precordial and Rt leg lead
What limbs detect anterior wall MI?
What leads detect lateral Wall MI?
V5-V6, I, aVL
What leads detect inferior wall ischemia?
- If a BP cuff is too narrow and loose, the reading will be artificially?
- if the cuff is too wide, what will be the reading?
- which is prefered?
- too wide
1. What are contraindications of IABP monitoring?
- negative Allen's Test
- preexisting vascular insufficiency ex. Raynauds
1. what is the second most come IABP monitoring site?
2. What are its special attributes in terms of altered reading?
1. Dorsalis Pedis
2. 20 to 30mmHg higher systolic and 10 to 20mmHg lower diastolic
Femoral artery IABP complications?
pseudo-aneurysm and theroma formation
asceptic necrosis of femoral head - especially in children
What are the primary indications for CVP monitoring?
- Monitor of fluid status shifts
- Need for hyperailmentation
- Venous Air Embolism (VAE) aspiration
- Lack of peripheral access
- Expected blood loss
What are CVP contraindications?
- Renal Cell tumor extension into RA
- Fungal Tricuspid
- Anticoagulation or bleed disorders
- ipsilateral carotid endarterectomy
- Is CVP reading a good indicator of LV fx?
- CVP reading will be higher in what conditions?
- NO - Poor indicator
- increased in RV failure and tricuspid disease
1 Whats the most common site for CVP access?
3. Lft sided cannulation increases risk of what?
1. Rt IJ
2. Offers the most direct route to superior vena cava
3. Vascular errosion
- pleural effusion
- chylothorax - lymph
- lft IJ significantly smaller in 1/3 population
1. What position is used for insertion and what is you intending to prevent?
What does the a-wave correlate with?
What does the c-wave correlate with?
1 atrial contraction
2. beginning Vent contraction -backflow and tricuspid buldge toward atria
3. x-wave tricuspid - downward displacement
4. v-venous return
5. tricuspid opening - decreases pressure
1. What cause CVP giant P waves?
2. Cannon Waves
- AV dissociation - RA contracts against closed tricuspid
Define the Reticular Activating System
T/F RAS is both inhibitory and exitatory?
- it is the polysynaptic pathway that travels from brainstem to the cerebral cortex that is intimately concerned with with the electrical activity of the cereberal cortex
Sleep can occur in what two ways?
1. Slow wave (most of sleep each night)
2. and abnormal channeling of signals and RAS activity may not be depressed = desynchronized sleep
Slow wave sleep is characterized by what type of waves?
During slow wave sleep SNS and PNS are inversely active?
What is the result?
1. Delta waves
2. SNS decreased and PNS increased
3. = 10-30% decrease in BP, HR, breathing, and BMR
Desynchronized sleep has what waves?
How often do they occur?
T/F associated with active cerebral cortex and despite skeletal inhibition, eyes exhibit rapid movements REM?
1. Beta waves - Low voltage - similar to wakefulness
2. q 90 minute cycle for 5 to 20 minutes
What is the relationship btw cereberal activity and freq of brain waves?
2. what are the brain wave classifications?
1. direct relationship
2. alpha, beta, theta, and delta
Alpha waves indicate?
Absent during sleep?
- 8-12 cycles/sec 50 microvolts
1. Beta waves indicate?
1. High alert or REM
2. Low voltage - high frequency 13-30 cycles/sec < 50 microvolts
1. Theta wave indicate?
2. 4-7 cycles/s
- Delta waves indicate?
- presence of Delta waves suggests that the Cerebral cortex is released from RAS?
- Deep sleep or deep anesthesia/Organic brain dz
- Slow frequency < 4 cycles/sec
- What does BIS stand for?
- BIS number is proportional to wakefullness/Light?
- Bispectral index
- true - greater the number -> wakefulness
- Opioid do not influence state of consciousness at analgesic doses?
- BIS does not monitor muscle relaxation?
- BUT, lack of relaxation can alter reading?
1. What BIZ score indicates deep hypnotic state?
2. What score indicates General anesthesia
1. What are situations that may give you falsely elevated BIS?
What are two things that will decrease BIS?
What may cause an artificially low BIS?
1. over temporal artery
2. blinking or rolling head
1. What are the effects of anesthesia on temperature?
1. General Anesthesia inhibits thermoregulation
2. Regional anesthesia- regional vasodilation
3. Redistribution dt vasodilation
1. What are the three phases of temperature loss?
Phase I = 1-2 degree C during the first hour d/t redistribution
Phase II = gradual loss over next 3-4 hrs.
Phase III = equilibrium
What are deleterious effects of hypothermia?
- platelet aggregation
- < drug metabolism
- < wound healing-> infection
- vasoconstriction - increase PVR
- lft shift Oxyhemoglobin shift
- impaired renal fx
- Altered mental status
- postop protein catabolism and stress response
Esophageal probe must be in what portion of the esophagus?
1. distal third of esophagus
Which temp method theoretically gives you brain temp?
1. tympanic - d/t auditory canal blood supply is the external carotid - proximity to hypothalmus