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219 Cards in this Set

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1. What are the 9 steps in a typical general Anesthetic procedure?
1. Pre op Eval
2. Patient prep1 (Preop holding)
3. Patient prep 2 ( OR)
4. Induction of Anesthesia 1
5. Airway Management
6. Induction of Anesthesia 2
7. Manitenance
8. Emergence
9. Recovery
2. What are the 6 steps in the preop eval?
1. Summarize general health, PMC, Allergies and medications.
2. Physical Exam ( Airway, lungs, CV)
3. Discuss with patient the benefits and risks of procedures.
4. Obtain informed consent.
5. Provide instructions ( meds, Npo)
6. Formulate a plan.
3. What 4 things takes place in paptient prep 1 in the holding area?
1. Vitals.
2. Confirm NPO.
3. Start and IV line, any invasive lines if needed.
4. IV sedative.
4. At minimum what 3 monitoring tools are attached in the operating room during the patient prep 2 stage? What should you confirm is still working?
1.A three lead ECG
2.Non invasive BP cuff
3.pulse oximeter
Confirm that the IV line is patent and running well.
5. The first phase of induction consists of what 2 steps?
1. Preoxygenation
2. IV induction with shorth acting drugs such as thiopental and propofol.
6. What are the three ways of airway management after the first part of inductions ( loss of consciousness) is achieved?
1. Mask Airway
2. Laryngeal Mask
3. Endotracheal Intubation
7. Where do you place a Laryngeal Mask?
In the patients Posterior Oropharynx, surrounding the glottic structures.
8. What do you do before you put an ET in?
paralyze the patient with a neuromuscular drug
9. Why does the ETT provide a more secure airway than the mask or LMA?
Because the ETT seals the trachea.
10. If the patient is at risk for aspiration of stomach contents....what kind of airway do you use?
ETT
11. Unlike hypnotic drugs such as propofol, inhaled anesthetics provide, __, ___, ___. which together make up the anasthetic triad.
1. Hypnosis.
2. Amnesia.
3. Analgesia.
12. What are the volatile inhaled anesthetics at room temperature?
Liquids. Thus a vaporizer is used to convert the liquids to gases.
13. Name 5 general steps used during maintenance
1. Deliver Anesthetic gas to provide adequate depth of anesthesia.
2. Give neuromuscular blocking drugs to maintain muscle paralysis.
3. Follow monitored parameters and intervene when necessary.
4. Add narcotics as needed to both lessen the requirenment of inhaled anesthetic agents, and to provide analgesia.
5. Give adjunctive drugs when indicated, like anti emetics.
14. What are the five steps used during emergence from anesthesia?
1. Reversal of residual neuromuscular blockade.
2. Discontinue inhaled anesthetic and administer 100% oxygen.
3. Extubation of the trachea.
4. Monitor vitals espesially oxygen saturation after extubation.
5. Continue oxygen by face mask during transfer to PACU.
15. Dont extubate until...
The patient follows commands.
16.what are the 3 most commonly used barbituates used for anesthesia?
Thiopental, Thiamylal, Methohexital
17. Why are drugs like thiopental and propofol good for neurosurgical operations?
They reduce ICP while preserving cerebral perfusion.
18. Besides depressing the myocardium directly, how do barbituates compromise C.O
Decrease pre load seondary to peripheral pooling.
19. What is responsible for the rapid termination of action of propfol and thiopental?
19. Redistribution away from the central compartment after a bolus.
Compare emergence from thiopental Vs Propofol
unlike thiopental, emergence from propofol is rapid even after long periods of continous infusion because of rapid clearance from the central compartment by hepatic metabolism.
who has a larger central volume of distribtution, children or elderly?
children have a larger central volume of distribution.
Does propofol make you vomit?
No, it appears to posses antiemetic activity.
What is so special about Etomidate?
minimal depression of cardiovascular and pulmonary function. Thus, it is ideal for patients with compromised cardiovascular system, cvd, hemodynamic instability.
Side effects of Etomidate
1) Pain on injection.
2) Supression of cortisol synthesis.
3) High incidence of post operative nausea and vomiting espesially when used with narcotics.
4) Myoclonic movements.
Does etomidate cause seizures?
No, it acts as a prominent anticonvulsant at high doses.
Even after continuous infusion the emergence form etomidate and propfol is...
rapid
Neuro wise, what does ketamine do?
causes the thalamocortical and limbic system to become functionally segregated.
thalamocortical and limbic system segregattion by ketamine causes what 3 symptoms...
unconsciousness, Amnesia and analgesia.
Describe emergence form ketamine...
Emergence occurs 10 to 15 minutes later. But profound disorientation may last 1.5 hours after a single dose or longer after continuous infusion.
Can you use ketamine on someone with high ICP
NO
What does ketamine to bronchioles?
Brochodilate, so it good for patients with bronchodyspastic disease.
Why does ketamine increase the likelihood of laryngospasm?
because of its sialogogic action ( drooling)
What does ketamine do to the heart?
ketamine causes stimulation of SNS which leads to an increase in HR and BP. However it directly causes a myocardial depressant action, which is usually offset by the SNS stimulation.
What are the 3 most important BDZ used in anesthesia?
Midazolam. Diazepam, lorazepam.
Recovery time from BZ can be...
Very high.
What is the half life of Flumazenil and what is the significance?
1 hour. Important because, resedation may occur unless given in subsequent doses or continous IV.
What can Flumazenil do to ICP?
Increases ICP in patients with a head injury.
How do opiods work?
Inhibit neurotransmitter release from dorsal root ganglion cells.
What are 6 CNS effects of morphine?
1. Analgesia
2. Drowsiness, mood alteration
3. nausea
4. Inhibition of corticotropin releasing factor
5. Inhibition of ADH release
6. Sleep disturbances
What are potential hemodynamic effects of morphine?
produces vascular dilation, and impairs baroreceptor reflexes leading to orthostatic hypotension.
What is the prototype for the phenylpiperidine class of opioids?
meperidine.
What does Meperidine have in common with buproprion and meropenam
Cauze seizures.
Meperidine causes greater------ -----, than both morphine or fentanyl
Hemodynamic instability.
Meperidine reduces the ____ commonly seen after anesthesia
Shivering
Fentanyl is 50 to 100 times ___ potent than morphine. Sufentanil is 5 to 15 times ___ potent than fentanyl.Alfentanil is four to 10 times____ potent as fentanyl. Remifentanil is two two to 10 times _____potent as fentanyl.
More. More.Less. more
Rank the diffrent "fentanyls" by potency
Sulfentanil > Remifentanil > Fentanyl> Alfentanil
Why is fentayl good for patients with significnat CAD
Because it completely attenuates the stress response to surgical stimulation and produces hemodynamic stability with littel myocardial depression.;
What is ketorolac?
non specific COX inhibitor IV agent.
Succinylcholine has ____ action
biphasic.
Side effects of Succinlycholine
1. Fasciculations, myalgias
2. Increased intraocular and intracranial pressure.
3. hyperkalemia.
4. Malignant hyperthermia.
nondepolarizing blocking drugs can be divided in to what two groups...
Benzylisoquinolones, and ammonio steroids.
_____ can occur with inhalational agents and lidocaine and Aminoglycosides, clindamycin and acute phenytoin therapy.
Potentiation.
Chronic anticonvulsant administration provides ____ to nondepolarizing agents and acute amd provides_____
resistance, enhances.
5 main classes of antiemetics...
5Ht3, D2, H1, and M receptors.
5HT3 antagonists end with___
setron
D2 antagonists...
Metoclopromide ( Reglan)
Odansetron is also called____ metoclopromide is also called ____. _____ is also good for migraines.
Zophran. Reglan. Reglan.
Glycopyrrolate....
anticholinergic agent.
who can get malignat hyperthermia with succinycholine
patinets with absent or non functioning plasma cholinesterases.
What are good places to put an IV in?
large Hand veins
Cephalic
Basilic
Antecubital Veins
Total body water is ___% of total kilogram weight?
50
How is total body water organized?
Total body water is 50% of total KGW
30% in intracellular
20% in Extracellular
Of the extracellular 15% is in interstitial and the other 5 % is in plasma volume
What is the composition of blood?
Plasma Volume (5% of TkgW) + Cellular components of blood (2.5% of TkgW) = 7.5% of TkgW
_____ diameter and _____ catheter allow for greater flow.
large, Short
________ solutions maintain plasma oncotic pressure better than _____ crystalloid solutions because they remain in the intravascular space longer.
Colloid. Crystalloid.
Crystalloid solutions remain the in intravascular space for...
Only 30 minutes. Crystalloid solutions equilibriate rapidly.
What solution is better at maintaining plasma oncotic pressure?
Colloid solution.s
What are some examples of colloid solutions?
5% albumin, 6% hetastarch.
Intraoperative blood loss for minimal trauma.....Moderate trauma.....Severe trauma....
0 to 2ml/kg per hour
2 to 4 ml/kg/hour
4to8ml/kg/hour
You replace each ml of blood lost with ___ ml of crstalloid solution..
3
crystalloid solutions rapidly equilibriate with the ____ ____ ____. Only ___ remains in the vascular compartment.
extravascular fluid volume. Only 1/3rd remains in the vascular compartment.
Formula for maximal allowable blood loss=
MABL= (EBV) X ( Starting HCT-lowest acceptable HCT) / Average HCT during blood loss.
One unit of packed RBCs will increase the patients HCT by ___ points
3
___ is the universal donor
O
___ is the universal Recipient
AB
Before you administer Blood make sure to...
Warm it. To prevent hypothermia.
When using pressurized IV fluid setups be sure to ___
Vent all air before administration to avoid air embolism.
The usual physiologic responce to hypovolemia is ____ and ___
Vasoconstriction and Tachycardia.
___ ___ patients should not receive muscle relaxants.
Myasthenia gravis.
What happens to the tone on the Pulse Ox as saturation gets lower?
The tone becomes lower.
How should you investigate the etiology of hypoxia?
Start with the patient and work back to the anesthesia machine.
What are common patient causes of hypoxia? (4)
1. Hypoventilation
2. Airway obstruction
3. laryngospasm, Bronchospasm.
4. Endobronchial intubation, esophageal intubation
What are some less common patient causes of hypoxia? (3)
1. Pneumothorax
2. Myocardial failure
3. P.E
What are machine and circuit related causes of hypoxia?
1. Circuit disconnection
2. Circuit obstruction
3. Oxygen Supply failure.
What is a physical exam finding with laryngospasm?
high pitched noise during inspiration.
What is responsible for a laryngospasm?
Secretions or stimulation to the posterior pharynx in the partially anesthetized patient.
How do you go about treating a laryngospasm?
First try to remove the irritating stimulus.

Remove an oral airway, suction posterior pharynx, relieve any painful stimuli.

Try breaking the laryngospasm by administering PPV with 100% oxygen.

Immediately intubate patient after paralyzing them with succinylcholine.
What is a physical exam finding with bronchopasm?
Wheezing.
What can be the cause of bronchospasm in an anesthetized patient?
Airway irritation from ETT or from aspiration.
Inadequate tidal volume can lead to....
Atelectasis and hypoxia.
What is usually a good tidal volume, and rate during surgery.
Tidal volume between 5 and 10 ml/kg and rate between 8 and 12 per minute.
How will an esophageal intubation, present. What do you do about it?
Absent breath sounds, low or absent ETCO2. Immediately reintubate.
How will a endobronchial intubation, present. What do you do about it?
Unilateral breath sounds ( usually right) wheezing. Withdraw the tube slightly.
What can you do to confirm a patent ( not kinked) ETT
Pass a suction catheter down the tube. Suction to tube while at it to remove any mucus plugs from aspiration.
Both pneumothorax and pulmonary emboli present with...
Hypotension and tachycardia
What is a common complication of carniotomies performed in the sitting position?
Air emboli
When can an air emboli occur?
Whenever a vein is open to the atmosphere at a lever higher than the right atrium.
Awake patient with hypoxia, what do you do...
Provide oxygen with face mask.

Check for upper airway obstruction, ex audible snores from the patient, rocking chest movements with out any visible air movements. Chin lift/jaw thrust, or inserting an oral airway.
In a ventilated patient, try to maintain ETCO2 between...
35 and 40 mmhg.
What are 3 conseqences of hypercarbia?
1. Increase ICP
2. Pulmonary artery hypertension.
3. Tachycardia
What do you always do first whenever you suspect a critical problem?
Ensure adequate oxygenation and ventilation.
What 2 physical exam findings are suggestive of narcotic overdose?
Pin point pupils and deep but infrequent spontaneous breaths.
Hypercarbia due to increased rebreathing of gases can occur under what setting?
Low fresh gas flow.
Exhaustion of the OC2 absorber.
Hypercarbia due to increased absorption of CO2 occurs during...
Insufflation of the peritoneal cavity with CO2 during lap procedures.
What are 3 big categories for causes of hypercarbia?
Inadequate elimination
Increased production
Increased absorption
Inadequate elimination of Co2 occurs with (6)
Airway obstruction from
COPD
Pulmonary edema
bronchospasm
mainstem intubation

Inadequate reversal of NMB
Rebreathing of gases due to low fresh gas flows or CO2 absorber malfunction
Increased production of CO2 can occur with (4)
Malignant hyperthermia
Sepsis
Thyrotoxicosis
Sodium bicarb administration
Rebreathing of CO2 is indicated by...
Increase in the INSPIRED CO2 on the capnograph ( not at 0)
BP should be checked every...
5 minutes.
Most anesthetic agents lead to cardiac contractility depression. One exception to this rule are...
Narcotics. But can indirectly depress BP by depressing sympathetic outflow.
An exagerrated decline in BP during PPV is a sign of..
Hypovolemia.
Extremely high levels of spinal blockade known as a total spinal can lead to...
resistant hypotension and bradycardia requiring immediate resuscitation.
Hypotension during an orthopedic surgery, could be from...
seen after release of a tourniquet,
Hypotension during aortic anneurism surgery...
Release of an aortic cross-clamp.
Vagally mediated reflexes causing hypotension and bradycardia/ asystole include... 5
1. Peritoneal stretch during hernia repair.
2. Insullfation of abdomen during lap.
3. Traction of the glove during eye surgery.
4. hypoxia
5. Light anesthesia
Whenever you see hypertension in an anesthetized patient, what do you do first?
Rule out hypoxia and hypercarbia, by ensuring adequate oxygenation and ventilation.
Why is sinus bradycardia in a child, during anesthesia, something to worry about?
Because it is often a sign of hypoxia/hypercarbia.
Is sinus bradycardia particulary worrysome in adults?
No.
Succhinylcholine induced bradycardia occurs in adults...
usually only after a second dose.
What can be used to treat most cases of venticular ectopy?
Lidocaine.
Mobitz type 3 suggests a...
Distal atrioventricular nodal disorder.
What are the causes of heat loss in the operating room?
Radiation 60%, evaporation 20%, convection 15%, conduction 5%
Define radiation, conduction, convection
Conduction or diffusion
The transfer of energy between objects that are in physical contact
Convection
The transfer of energy between an object and its environment, due to fluid motion
Radiation
The transfer of energy to or from a body by means of the emission or absorption of electromagnetic radiation
How can you reduce evaporative heat loss?
Airway humidifier.
Define Hyperthermia
A rise in temp at a rate greater than 0.5 degree Celcius per 15 minutes or 2degree celcius per hour.
What are 3 common causes of temperature elevation. What is the most dangerous.
Atelectasis, infection, sepsis.
MH, it must be ruled out and rapidly treated with dantrolene.
Anaphylactic VS Anaphylactoid reactions
Anaphylactoid reactions involves NON IgE mediated histamine release.
How do you treat Anaphylactic VS Anaphylactoid reactions
1. Discontinue Anesthetic if patient is unstable.
2. 100 % oxygen.
3. IV fluid Bolus.
4. D.O.C is epninephrine
5. Steroids, diphenhydramine might help.
What are four examples of Non critical events ?
1. Cant close peritoneum after abdominal surgery.
2. Patient is moving during surgery.
3. Patient is hurting during a regional anesthetic.
4. Patient is not waking up, after surgery.
Emrgence after surgery with isoflurane will take longer because...
Isoflurane is pretty soluble.
All patients with intraopertative ischemia require...
Further cardiac eval during the recovery period
Increased ICP can be associated with
Hypertension and bradycardia.
In terms of the airway anatomy, what are is the "11 criteria"
4 observations about dentition
2 for the mouth and pharynx
3 for the neck.

The more they vary from normal, the greater the chance of difficulty.
What are the 4 things you should observe while doing a physical exam on dentition?
1. The presence and size of teeth.
2. The distance between the upper and lower incisors in cm of fingerbreadths when the jaw is maximally opened.
3. Extent to which the maxillary teeth override the mandibular teeth.
4. The ease with which the mandible can slide forward ( prognath)
What is a good combination for easy airway management?
A large oral cavity combined with a small, mobile tongue.
What is the most commonly documented airway descriptor? whats number 2?
M.C is presence or absence of teeth.
2nd is the mallampati class.
What are the two most important features of the chin for airway management?
Mandibular space and tissue compliance.
Anatomical position of the mandibular space?
Bordered by the mandible anteriorly and laterally. Hyoid posteriorly.
What is the thyromental distance? and what is the significance?
The distance between the mentum and the thyroid/hyoid.

Airway risk is low if the thyromental distance is 3 fingerbreadths or greater and the tissue compliance is high.
What are you worried about while intubating an obese patient?
An enlarged pre epiglottic fat pad that can reduce airway access.
What are the 3 assessment points in the neck?
1. Asses full range of motion at the atlanto occipital joint and other cervical vertebrae.
2. Note any painful conditions or conditions associated with instability.
3. If the neck is short/ thick
What is the "sniffing " position?
Extension at the atlanto occipital joint and flexion at the remainign cervical vertebrae.
What is the problem, if the neck is too short?
The larynx takes a more cephaladad postion and may be too anterior to visualize during laryngoscopy.
What is the problem, if the neck is too thick?
Difficulty lining up the axis of the mouth, pharynx, and larynx.
How do you place a nasal aorway?
First lubricate, then pass through the nose in to the pharynx.

When passing a nasal airway, it should be directed parallel with the palate to avoid inappropriate placement.
Three reasons to not use a LMA and use and ETT
1. Airway control must be maintained for many hours.
2. When mechanical ventilation is planned.
3. Airway can be compromised by secretions or a foreign body.
Who is a good candidate for an oral airway?
A supine patient in whom the tongue tends to fall backwards closing the pharynx. ( A wooden tongue blade may be inserted to push the tongue out of the way.
Where should you tape the ETT
Maxilla and zygoma is better than mandible.
PPV should be provided at what volume and rate?
5 to 10 ml/kg . 8 to 12 per minute to maintain normal end tidal CO2.
Excessive pressure at the ETT placement site can lead to...
Tracheal mucosa necrosis and sloughing.
While doing a mask ventilation what are common causes of failure?
1. Leak
2. Air way obstruction(usually by the tongue)
How does a pulse plethysmograph work?
Senses tissue blood volume by the attentuation of light emitted from and detected by a probe that is placed over an extremity.
The elecrtic signal produced by a pulse ox or pulse plethysmograph , what is the amlitude/ frequency proportional to?
Amplitude- Blood flow
Frequency- Heart Rate.
what is a pulse oxomiter?
Pulse plethysmograph+ Infrared light source and detector.
Whats the diffrence between a pulse plethysmograph and a pulse ox
A pulse ox also has an infrared light source, so besides detecting pulse it can also detect oxygen saturation of hemoglobin.
What are the two components of an arterial pressure pulse?
A pressure wave ( propogated at 5 to 10m/sec)
A flow element ( 0.3 to 0.5m/sec)
What generated the pressure wave in an arterial pressure pulse? and what sustains it?
Generated by the mechanical contractions of the heart.

Sustained by the viscoelastic properties of the arteries.
What is the reason for diffrent blood pressure measurements at diffrent arterial locations?
The alteration of the pressure pulse from the arch of the aorta to the capillaries.
What is the best cuff width to use in order to (indirectly) measure BP
40% of the cirucumference of the arm.
Is it better to use a cuff that is too big or one that is too small.
better off using one that is too big.
What happens to the BP reading if the cuff is smaller than 40% of arm cirumference?
it will give a reading that is higher than the actual BP
How can you monitor the electric and mechanical activity of the heart with out looking at the monitor?
An Audible QRS indicator( electrical)
An Audible pulse plethysmograph ( mechanical)
What 3 lead ECG combo, has a 96 % sensitivity in detecting ischemia compared to a 12 lead?
Leads 2, V5 and V4.
What is generally considerd diagnostic of myocardial ischemia?
St- segment depression, of atleast 1mm measured at the J point + 60 msec in any lead lasting at least 1 minute.
Make sure that your ECG monitor has a bandwith of...
as low as 0.05 if not you cant pick up on Myocardial ischemia.
How do you know if there has been a 1% change in arterial hemoglobin saturation?
Change in tone of the pulse ox.
How is airway pressure measured?
by a pressure gauge on the inspiratory limb of the breathing circuit.
Peak inspiratory pressure is dependent upon...3
Resistance to flow in the breathing system.

Compliance of chest wall/lungs

breathing circuit
What is the normal range of peak inspiratory pressure in a normal person?
5 to 30 cm H20
What are some problems caused by hypothermia?
1. Depressd cerebral function.
2. Delayed awakening from Anesthesia/prolonged NM blockade.
3. Post op shivering which can increase o2 consumption a 100%.
4. Interferes with coagulation leading to problems with hemostasis.
During surgery a urine output of atleast____ is acceptable.
0.5 ml/kg per hour.
If you see red tinged urine.....
1. Traumatic catheter insertion
2. hemoglobinemia from blood transfusion reaction
Before interpreting the pressure from an arterial catheter..... the transducer must be______. This will be valid as long as?
Zeroed.
As long as the relative vertical distance between the heart and the transducer remains unchanged, the zeroing of the transducer remains valid.
The Central venous pressure will reflect the _______ pressure and can serve as a surrogate for ______ in patients with notmal lungs.
Left atrial pressure.
Pulmonary capillary wedge pressure.
For central access and measurement of CVP, a catheter can be inserted through what 3 veins?
External/ internal jugular.
Subcalvian
A central line ends where?
tip lies in the distal superior vena cava just above the right atrium.
What is the characteristic CVP tracing?
a, c, v waves with x and y descents.

A- Atrial systole
C- Bulging of tricuspid back toward atrium during ventricular systole.
V- Passive right atrial filling.
You suspect an air embolus....good thing you have...
central venous access.
What do all PA catheters havein common? what is their function.
1. Proximal Lumen: For the measurement of CVP.
2. Distal Lumen: measurement of PA pressure.

Distal end which contains
3. Inflatable ballon: Flow directed placement and to obtain the PCWP

4. Thermistor: Measure the core temp and cardaic output
Congest heart failure

MAP:
CVP:
PA:
PCWP:
CO:
SVR:

Treatment?
MAP: Low
CVP:High
PA:High
PCWP:High
CO:Low
SVR:High

Ionotrpic agent + vasodilator
Hypovolemia

MAP:
CVP:
PA:
PCWP:
CO:
SVR:

Treatment?
MAP: Low
CVP:Low
PA:Low
PCWP:Low
CO:Low
SVR:High

Give fluids
Vasodilation

MAP:
CVP:
PA:
PCWP:
CO:
SVR:

Treatment?
MAP: Low
CVP:Low/norm
PA:Low/norm
PCWP:Low/norm
CO:high
SVR:low

Vasoconstrictor

Give fluids
Hypertensive

MAP
CVP
PA
PCWP:
CO:
SVR:

Treatment?
MAP: High
CVP:norm
PA:norm
PCWP:norm
CO:norm
SVR:High

Vasodilator

Give fluids
The minimal monitoring standards for anesthesia include...4
1. Oxygen
2. Ventilation
3. Circulatory Status
4. Body temperature
How can you differentiate NMS from MH?
The muscle Rigidity in NMS can be reversed with non depolarizing neuromuscular blockers.
What are early signs of MH?
Increase in ETCO2 and then sinus tachycardia
How can you get the cardiac output using a PA catheter?
Using the thermodilution method.
what kind of anesthesia should you use for a cesarian section?
Regional Anesthesia, proven to better for both mother and child.
What are 2 absolute contraindications to spinal and epidural anesthesia?
Infection at the injection site
Coagulopathy
What is the chemical structure of a local Anesthetic?
A hydrophilc group linked to a lipophilic structure by a carbon chain.

Hydrophilc group= Tertiary amine
Lipophilic structure= has an ester or amide bond.
How are esters metabolized,
Amides?
Esters= Hydrolyzed in the blood or liver.

Amides= Generally dealkylated in the liver.
How do local Anesthetics work?
Diffusing in to the axon and blocking the sodium channels.
What is the PKA of all local Anesthetics? why is that?
7.5-9.5

Tertiary Amine, so All are weak bases
How are the local anesthetics dispenced?
Dispensed dissolved as salts of strong acids.
The rate of onset of each drug depends upon?
1. Concentration
2. MW
3. Degree of protein binding
4. Degree of Ionization.
What form of the local anesthetic enters the cell?
The unionized form enters the cell.
What form of the local anesthetic is active inside the cell?
The ionized form.
What does adding Sodium bicarbonate with a Local anesthetic acheive?
Increase the ratio of unionized drug.

Decrease the onset of time of block.

Increase the risk of percipitation of the solution.
What two esters have a rapid onset?

What two esters have a slower onset?
Rapid= Lidocaine, Mepivacaine

Slow= Bupivacaine, Tetracaine.
The duration of block ( how long the drug remains at the therapeutic concentration at the site ) is dependent upon?
Uptake from the site is dependent upon

1. drugs diffusion
2. Solubility
3. protein binding
4. blood flow in the area.
How can you increase the duration of the block?
By the addition of vasoconstrictors.
What 3 LA have a short duration of action?

What 2 LA have long duration of action?
Short duration of action= Procaine, Chloroprocaine, Lidocaine

Long= Pivacaine , Tetracaine.
Systemic toxicity of a LA is related to?

What is that dependent on?
Related to blood plasma level

Dependent on rate of uptake compared with rate of clearance of drug.
What kind of nerve blocks tend to produce the highest blood levels?
Intercostal nerve blocks.
Clearance of LA is dependent on 2?
Redistribution and metabolism.
The ester________ is rapidly cleared from the blood. Lowest blood levles.


The ester______ is has a long half life and is toxic.
Chlorprocaine.

Tetracaine.
Because vasoconstrictors decrease drug uptake. They decrease peak drug levels, and allow a _____ total dose of drug to be given.
higher.
major side effect of bupivacine
Sudden cardiovascular collapse.
What is the least toxic ester.

what is the least toxic amide.
Chloroprocaine

Prilocaine.
Side effect of Prilociane?
Methemoglobinemia.
Motor blockade is greater then sensory blockade for....
Etidocaine.
The most toxic ester..
Tetracaine.
Less cardiotoxic than bupivacaine...
Ropivacaine
Similar pharmokinetics as lidocaine...
mepivacaine.
highest potency...
Bupivacaine, Tetracaine
lowest potency...
Chloroprocaine, Procaine.
The A fibers...
Somatic motor and sensory.

large and highly myelinated.

Require highest concentration of drug to block.
B fibers....
Small and slightly myelinated....

Vascular smooth muscle.
C fibers...
Small and unmyelinated

Sensation of pain and temp. (easiest to block)