Exam 1 Flashcards
Intracellular water volume is how much of body weight and found mostly where?
2/3, and mostly found in muscle mass
What is your total body water?
50-80%
Extracellular water is how much of body weight and where is it mostly found?
20%, and mostly found in CV system and interstitial spaces
Plasma is what percentage of extracellular fluid and how much of blood volume?
25% of extracellular, and 50% of blood volume
Blood volume is how much of your total body weight?
approx 8% (15% arterial and 85%venous)
Formula for male blood volume?
75ml/kg
Formula for female blood volume?
65ml/kg
Formula for neonate blood volume?
85ml/kg
Formula for preemie blood volume?
90ml/kg
How does body water differ from males, females, elderly, and newborns?
Male-60% water, Female-50%, elderly-45-55%, newborn-75-80%
What are the major components in intracellular?
K+, Mg, Phos, proteins
Major components of extracellular fluid?
Na+, Ca++, Cl-, HCO3, Glucose
What is orthostatic BP?
systolic bp decrease 20mmHg or more from supine to standing or sitting. Indicative of 6-8% volume deficit
What are compensatory responses to intravascular deficit (orthostatic hypotension)?
increase in HR but not if beta blocked
How much intravascular volume loss is need to cause a decrease in arterial BP?
30%
Lab signs of hypovolemia
Increased Hct, metabolic acidosis, urine specific gravity 1.010, urine osmolality >450
NPO fluid calculation is What?
1st: 10kg= 4ml/kg/hr, next: 10kg= 2ml/kg/hr, each kg over 20kg 1ml/kg/hr. (quick way= (weight + 40 ml)x hrs NPO)
What is needed to obtain informed consent?
Make sure patient understands: 1. type of surgery being done, 2. Understand anesthetic type, risks and questions about anesthesia, 3. Explain possible complications and document
When reviewing chart make sure surgical consent is signed by whom?
(Adult non-emergent)-Patient or legal guardian
(Emergency)- closest relative or surgeon
(under 18)- signed by parent or closest legal guardian
Old anesthetic records are helpful why?
can give info on past difficult anesthetics and intubations
What other allergy is associated with an allergy to Avocado, Bananas, Chestnuts?
Latex
If anaphylaxis occurs intra-operatively and no source can be identified what could be a possible source?
Latex
What Meds should you continue prior to surgery?
4-As DHGTI- Antihypertensives, Antianginal, Anticonvulsants, Asthma, Digitalis, Hormones, GERD, Thyroid, Insulin (for insulin see pg. ….)
What is Malignant Hyperthermia?
genetic inability to breakdown succinalcholate & anesthesia which causes increases in Temp, Ca++ release, contractions, CO2, HR, acidosis, Rhabdo
Treatment for Malignant Hyperthermia?
Dantrolene
If patient has taken steroids in last 6 months what med should be given?
Hydrocortisone 100mg q6hr
Up to what time can a patient have black coffee before sugery?
2hrs (clear liquid as long as no creamer)
Up to what time can a patient have any food they want before surgery?
up to 8hrs
Up to what time can a patient have light meal or for baby infant formula/non-human milk before sugery?
up to 6 hrs
Infants can have breast milk up to what time before surgery?
4hr
What lab should be done on all women under 50?
Serum or urine HCG (pregnancy)
Abnormal blood chemistry such as electrolytes are most common in what patient populations?
Chronic diuretic therapy, cardiac history, renal disease, diabetic
In assessment of patient preparing for emergent surgery what key evaluations should be made?
- last oral intake (always presume full stomach), 2. get type and cross and is blood available, 3. Check/get IV access or lines, 4. Allergies, 5. Pertinent med hx and system review
If child is scheduled for non-urgent surgery and has upper respiratory infection what should you do?
- If severe symptoms postpone 4 weeks
- If case under general anesthesia consider risk factors and risk/benefit (avoid ETT, consider LMA, hydrate, humidify, anticholinergics?)
What are the goals of general anesthesia?
Amnesia, analgesia, skeletal muscle relaxation, and control of SNS responses
What is the gold standard for local anesthetics?
bupivacaine last 2-3 hrs
Describe the ASA classification system?
P1= normal healthy pt. P2= pt with mild systemic disease P3= pt with severe systemic disease or multiple mild disease P4= disease is constant threat to life P5= Moribund pt. not expect to survive without surg P6= brain dead organ donation E = emergency qualifier and can be added to each class
Major intracellular and extracellular cations?
- intracellular- Na+
- extracellular- K+
What labs would be indicators of possible hypovolemia?
increase hematocrit
metabolic acidosis
urine specific gravity 1.010 (normal 1.010-1.025)
urine osmolality >450
Absorption of irrigation solutions during TURP’s or endometrial ablations can lead to what?
hyponatremia
What is the treatment for hyponatremia?
Hypertonic Saline, correct underlying problem (abandon surgery), restrict fluids, increased H2O loss (diuretics if hypervolemic).
What happens with K+ levels with each 10mmHg decrease in PCO2?
They decrease approx 0.5mEq/l (K+ high with acidosis and decreases with alkalosis)
What is the treatment for hyperkalemia?
IV calcium 1gm
Alkalosis (hyperventilate, IV NaHCO3)
Albuterol 5mg/3cc saline q20min
Glucose 25gm followed by 10-15units reg insulin
How would hypokalemia show up on an EKG?
ST depression, flattened T waves, widened QRS, **U waves (after T waves)
How would hyperkalemia show up on EKG?
Widened QRS, shorted QT, peaked T waves, cardiac arrest (most detrimental)
What are some causes of hypocalemia?
Alkalosis
citrated from transfusions
renal failure
parathyroid damage or removal
What symptoms often occur with hypocalcemia?
Seizures, increased membrane excitability, laryngospasm, myocardial failure, or bradycardia.
How do you calculate maintenance fluids for surgeries with minimal blood/fluid loss?
2ml/kg/hr usually LR or D5LR this is minimum for all pts
How much replacement fluid should be given for minimal surgical trauma (breast biopsy, superficial)?
2ml/Kg/hr
How much replacement fluid should be given for moderate surgical trauma (appendectomy, laproscopic surgery, hysterectomy)?
2-4ml/kg/hr
How much replacement fluid should be given for Extreme surgical trauma (bowel resections, highly invasive prolonged)?
4-8ml/kg/hr
How do you calculate acceptable blood loss?
acceptable blood loss=
EBV* (start hct-lowest accepted hct)/ start hct
How is volume replaced when there is moderate blood loss <20% total blood volume?
With 3ml of crystalloid/ 1ml of blood loss
How much sodium is in LR, D5.45, and 0.9%?
LR= 600mg/100ml (K+ in LR can accumulate in renal pt)
D5.45= 450mg/100ml
0.9%= 900mg/100ml (may cause hyperchloremic metabolic acidosis)
pg. 392 N&P
When is albumin/colloids used?
after burns or large protein loss, when fluid replacement is 3-4 liters behind, each gram of albumin binds 18ml water, acts as carrier protein for several drugs
For an elective surgery how many IV’s and what size?
One 18 or 20 gauge IV
For a bowel case what type of IV access would you have?
Two 16 or 18 gauge IV’s
For a unstable shock pt what type of IV access?
2 large bore IV’s and CVP (central line)
What type of access for local sedation case or poor venous access?
one 20 gauge
What are some complication of IV insertion/administration?
Cellulitis, lymphangitis, thrombophlebitis, air embolism, extravasation, injection of wrong drug, inadvertent intra-arterial injection
What types of cases would you normally have CVP monitoring with central line?
sitting crani’s, large blood loss or fluid shifts, rapid infusions, pts with pre-existing cardio/resp disease, compression of great vessels, or pacer insertion
What is the best way to recognize venous air embolism?
2D echo superior to precordial doppler
What monitoring is necessary for sitting cases (such as crani’s) when surgical site is higher than heart?
- Doppler auscultation between 3-6 intercostal space on right side to listen for air embolus.
- Will also need central line with stop-cock to aspirate air if mill wheel murmur is heard.
What lead is best for arrhythmia detection?
lead II
What lead is best for ischemia detection?
modified V5
What things does monitoring EKG help identify?
- cardiac arrhythmias
- myocardial ischemia
- electrolyte changes
- heart rate changes (audible QRS should be turned on to help identify changes)
Other than arterial monitoring what type of BP measurement is most accurate?
Oscillometric- most automated cuffs use this method and correlates well with arterial mean and diastolic bp
What are indications for arterial bp monitoring?
Cardiac surg, deliberate hypotension, cranis, major vasc surg, extensive trauma, inability to measure bp with cuff, unstable cardio or respiratory disease, large blood or fluid losses, compression of great vessels.
What parameters can be derived from A-line that cannot be from cuff bp?
circulating blood volume, and beat to beat changes in bp (such as hypovolemia with positive pressure ventilation.)
What are some complication of A-line insertion?
ischemia, embolism, hemorrhage, thrombosis, infection (most common), av fistula, aneurysm
Somatosensory evoked potentials (SSEP’s) are used for what?
- monitor cerebral function and ischemia with cerebral/neuro/spinal/CEA procedures,
- better to have less/balanced anesthesia when using SSEP’s (no NMBA or N2O)
Oxygen delivery monitors use mass spectrometry what are its limitations?
-Cannot sense pressure changes, ventilatory quality/volume, or tissue perfusion.
What are some causes of low pressure alarms on vent?
- disconnect
- major leak (tracheal tube or cuff, breathing system)
- failure of gas supply to vent
What are some causes of high pressure alarms on vent?
secretions tubing kinked coughing bronchospasm surgical retractor surgeon leaning pneumothorax
How would you calculate tidal volume for adult and ped?
8-10ml/kg for adult
1ml/lb for ped
Where would you place to detect right mainstem intubation? What about upper airway obstruction?
- left side of chest
2. sternal notch
Errors with pulse oximetry can be caused by what?
electrocautery interference carbon monoxide poisoning venous congestion synthetic fingernails dirt adhesives **dye indicators (methly blue cause transient decrease in pulse ox) motion light warmers
What does BIS monitor do and what is optimal range for general anesthesia?
measures depth of anesthesia extrapolates from EEG
45-60 optimal for GA, (0=flat line EEG, 100=awake)
not reliable in prone position due to sensor location
What can cause increase in baseline for ETCO2?
- exhausted CO2 absorber
- calibration error
- H2O in CO2 analyzer
- defective expiratory valave
Where would you like to keep ETCO2?
29-34 (low end)
On normal capnogram what does each point delineate? (pg. 29 of monitoring notes)
A= beginning of exhalation AB= anatomic dead space being exhaled BC= ascending limb represents increase conc CO2 CD= alveolar plateau containing mixed alveolar gases D= ETCO2 DE= descending limb and inspiratory phase rapid CO2 decrease
What is Curare cleft or notch on capnogram?
asynchrony between intercostals and diaphragm
inadequate muscle relaxant reversal
What should you do if you see spontaneous breaths on ETCO2 graph?
adjust vent settings, give agent, narcotic, muscle relaxant
How many ml can Raytex sponges hold wet and dry?
Dry=15
Wet=10
How many ml can Minilap sponges hold wet and dry?
Dry=40
Wet=25
How many ml can Regular lap sponges hold wet and dry?
Dry=75
Wet=40
How many ml can Gyn lap sponges hold wet and dry?
Dry= 150
Wet=65
How many ml can kidney basin and bulb syringe hold?
Kidney basin= 500ml
bulb syringe= 160ml
What are methods of heat loss and definition of each?
- conduction- heat from patient to OR table
- convection- heat transferred to air motion (12%)
- radiation- pt heat transferred to air (60%)
- evaporation- skin and lungs (H2O loss 25%)
Major complication of hypothermia?
Wound infection pg. 320
Who is at greatest risk for hypothermia?
infants and small children elderly critically ill long cases extensive abdominal or thoracic cases
What is the normal and minimal urine output?
normal= 1ml/kg/hr
minimum acceptable= 0.5ml/kg/hr
Prior and during position changes what should be done?
pre-hydrate
move slowly
decrease anesthetic agent to decrease vasodilation
What factors cause injury to bone and soft tissue?
- muscle relaxants can potentiate
- pressure >70mmHg applied constantly over >2hrs can cause irreversible ischemia and pressure alopecia
In what position does ocular injury most commonly occur?
Prone
What is Grade 1 nerve injury?
Neuropraxis= response for blunt force or compression, temporary dysfunction, slight demyelination with axon degeneration
What is grade 2 nerve injury?
Axonotmesis= destruction of axons, and myelin sheath without damage to supporting matrix, axon can regenerate and function may be restored
What is grade 3 nerve injury?
Neurotmesis= crushed, avulsed or severed nerve fibers connective tissue and schwanns sheath are completely disrupted, loss of function
What is the most common nerve injury?
Ulnar neuropathy
What is treatment for hypotension after position changes?
volume replacement
What is major concern with trendelenburg position in cardiac patients?
increased venous return causes increased myocardial oxygen consumption in pts with CAD
Zone I of lungs creates what in absence of perfusion?
Alveolar dead space (alveoli vented but not perfused)
In lateral position what happens to perfusion of lungs?
- down lung becomes zone 3= increased perfusion decreased ventilation (decreased tidal volume and increased congestion)
- up lung- receives ventilation preference but decrease perfusion
- V/Q mismatch
In supine position what nerve injury can take place?
Brachial plexus (avoid extending arm >90 degrees)
After changing positions what should you always do?
Check breath sounds to make sure ET tube still in right place (especially prone position turning)
What types of cases most commonly cause ischemic optic neuropathy?
Spine cases
Ischemic optic neuropathy are exacerbated by what conditions?
Anemia, hypotension, improper positioning, DM, vascular disease, smoking, glaucoma, long cases, prone position
In lithotomy position an obese patient may have this?
V/Q mismatch from visceral forces beneath diaphragm
