Exam 2 Flashcards
3000 mL/min
*VE = Minute Ventilation
Airway Pressure at End Expiration is maintaned above Ambient Pressure. _____ is Applied when Positive Pressure is maintained between Inspirations that are Delivered by a Ventilator
Positive End-Expiratory Pressure (PEEP)
*Maintains some pressure in the airways, where the Pressure Guage does not return to Zero between Inspirations but Instead is maintained at the Chosen PEEP Value_- Holds the Alveoli Open_ to Prevent Atalectasis
Local Anesthetics in the ____ Form Remain at Receptor Sites Longer, while Local Anesthetics in the ____ Form Rapidly Penetrate Membranes
Cationic (Charged)- Remains at Receptor Site Longer
Non Charged- Able to Rapidly Penetrate Membrane
*First you want the Drug in the Non-Charged Form so that it can Penetrate the Nerve Membrane, then Switch to the Cationic Form so that it can Remain at the Receptor Site Longer
*The Non- charged Form Penetrates the Membrane of the Nerve. In order for it to become Active it must convert itself to the Cationic Form. The Cationic Form cannot Penetrate the Membrane and therefore stays at the receptor site longer
Onset is Dependent on the pKa of a Drug. As the pKa moves further Away from Tissue pH (7.4), it has a ____ Onset of Action
Slower
Ex. Procaine with a pKa of 8.9 has a very Slow Onset. Lidocaine with a pKa of 7.7 has a Very Fast Onset (Closer to tissue pH = 7.4)
*All Local Anesthetic pKa’s will be Above Tissue pH of 7.4. As pKa Increases Further from 7.4, you have a slower and slower Onset
*Photo: Most Important- Know the Top Four- On Exam
True/False: Lidocaine and Bupivacaine are the Two most Commonly Used Local Anesthetics. Lidocaine has a Faster Onset than Bupivacaine
True
*The pKa of Lidocaine is Closer to Tissue pH (7.4), than Bupivicaine
Highly Perfused Areas will have ____ Systemic Absorption, while Poorly Perfused Areas will have _____ Systemic Absorption
Faster Systemic Absorption- Highly Perfused
Slower Systemic Absorption- Poorly Perfused
*Duration of Action is also affected by Tissue Blood Flow
_*_Ex. Mucous Membranes and Intercostal Muscles have More Blood Flow to the Area, More Systemic Absorption, Less Likely to have an Effect Locally, and More Likely to have Side Effects
*Highly Perfused Areas have Faster Systemic Absorption, and Therefore Shorter Duration of Action
*Poorly Perfused Areas have a Much Longer Duration of Action
______ Nerve Block Indications Include:
Extraction of Canine
Extraction of Incisor
Extration of Premolar
Removal of Small Nasal Mass
Infraorbital
*Contraindication: Extraction of Molar
Peripheral Nerve Block that Provides Anesthesia to the Elbow and Distally that is Indicated in:
Radius/Ulna Fractures
Toe Amputations
Carpal Arthrodesis
Brachial Plexus Block
*If A Patient Fractured its Humerus, doing a Brachial Plexus Block does NOT Help. Only Desensitizes the Elbow and Distally- KNOW THIS
True/False: When Performing Cranial Epidurals on Sheep and Goats, you tend to hit CSF Fluid commonly and therefore should Decrease your Epidural Dose by HALF
True
*In any Species, if you see CSF Fluid within your Epidermal Needle, Decrease the Dose by 1/2 to prevent the drug from traveling to the Brain
*If you get CSF Fluid and you are dosing for an Epidural Space, make sure to lower your Dose
When Performing a Cranial Epidural, what do you do if you Puncture the Dural Sac?
Reduce the Dose by Half
Disadvantages of Which Cardiovascular Drug:
SEVERE Vasoconstriction- Decrease Tissue Perfusion
Increase Oxygen Consumption
Tachyarrhythmias
Tissue Hypoxia
Epinephrine
Cardiovascular Drug that is an Alpha 1,2 and Beta 1,2 Agonist that is used to Treat Routine Hypotension
Ephedrine
*Ephedrine, Dobutamine, Dopamine and Phenylephrine- Common Drugs that are used to Treat Routine Hypotensive Cases
Two Indications for the Use of Colloids
Shock
Hypoproteinemia
True/False: Be Cautious when Administering Fluids to Patients with Cardiac Disease or Renal Disease, because they cannot deal with a large volume of fluid quickly
True
Cystalloid Fluid Replacement that is a Balanced Electrolyte Solution that Contains Calcium and is a Common Choice for Anesthetized Patients
Lactated Ringers Solution (LRS)
*Lactate as Alkalinizing Agent
*Contains Calcium- Caution if Transfusing Blood because the Calcium will Interfer with the Anticoagulants leading to Blood Clots
Synthetic Colloid that is Pectin based and Metabolized by Amylase that Increases the Plasma Volume by at Least the Volume of Fluid Administered
Hetastarch (Vetstarch)
*Stays in the Intravascular Space a long time- we dont want to Overhydrate the Patients so we only give 2-5mL/kg/h
*When you give Hetastarch, the Patients Amylase will go through the Roof- Know this
B. 1 Drop/2 Seconds
At ____% Blood Loss, the Patients PCV will Be 20%. For Oxygen Carrying Capacity, we Need a Minimum Hemoglobin of _____mg/dL for Appropriate Delivery of Oxygen (DO2) to Tissues (PCV 21%)
20%
Hb 7 mg/dL
* 7mg/dL of Hemoglobin is the MINIMUM where you can still carrying oxygen to tissues. 7mg/dL is Equivalent to a PCV of 21% (7x3). If we have a Patient with acute blood Loss and PCV
Balanced Electrolyte Solution that is made of Water, Electrolytes and an Alkalinizing Agent that Causes No Fluid Shifts between ICF and ECF
Crystalloid
*Redistribution Occurs!!!- How Much Stays in the Intravascular Space after 15 Minutes? 20-30%. For Every 1mL of Blood Loss you are going to give 3-4 mL of Cystalloid
External Chest Compression Theory used for Cats and Dogs
where Arterial Flow is Caused by Direct Compression of the Ventricles
Cardiac Pump Theory
*In smaller patients if you compress their chest in the right place you will actually be able to compress their ventricles and move blood foward
For External Chest Compressions in Medium to Large Dogs you Place 1 Hand on Top of Other Parallel at the ____ Part of the Chest and Apply Even Pressure using Palm of Hand
Widest
When Monitoring the Effectiveness of CPCR, What is the Most Important Indicator of Survivability?
ETCO2
*Capnograph will be the most Effective Tool you can Have
*If you have Greater than 20mmHg at 20 Minutes of CPR, you have a Higher Likelyhood Return of Spontaneous Circulation (Patient is Coming Back to Life)
*If you have Less than 10mmHg at 20 Minutes of CPR Spontaneous Circulation is Unlikely to Occur (Patient Dies)
Drugs that Provide Mild to Moderate Pain Relief that are Anti-Inflammatory, Analgesic, and Antipyretic
NSAIDS
Review of Arachidonic Acid Cascade
NSAIDS Stop the Production of Prostaglandins from Arachidonic Acid (AA)- Most Important
*NSAIDS Block COX (Cyclooxygenases) therefore the Arachidonic Acid cannot turn into Prostaglandin
COX ___ Works on the Mucosa to Prevent Erosions and Promote Healing and is Also an Anti-Inflammatory
2
*COX 2 Also has some Renal Protection Fuctions
COX ___ is involved in Fever Initiation
3
Cyclooxygenase ____ is Responsible for:
Vicero-Nociception
Thermal Stimulation
Involved in Constitutive Functions with COX 2
Cyclooxygenase 1 (COX 1)
Most Commonly used COX 2 Preferential NSAID That is Used Widely in Dogs that is Formulated as a Tablet or Parenteral with a Duration of 12-24 Hours with Side Effects Including Nephrotoxicity, Hepatoxicity, and GI Ulceration
Carprofen
*Great for Pre and Post Op Surgery because you can Administer the Parenteral Formulation prior to Surgery and send the Patient home with the Oral Chews
COX 2 Selective NSAID that is a Once a Day formulation (Duration 24 Hours) used in Dogs and Horses with Side Effects Including Abdominal Pain, Diarrhea, Urticaria, and PU/PD
Firocoxib
Ventilatory Status was Assessed and there is Increased PaCO2. Is this Patient Hypoventilating or Hyperventilating?
Hypoventilation
*PaCO2 > 45mmHg is Increased = Hypoventilation
*PaCO2 is Decreased = Hyperventilation
Descending Inhibitory Pathway that is an Important Relay for Descending Facilitative and Inhibitory Modulation of Nociceptive Input
Periaqueductal Gray Matter (PAG)
Central Sensitization is Fundamentally Different from Peripheral Sensitization because it Allows Low Intensity Stimuli and Low Threshold A Delta Fibers to Cause Pain as a Result of ____ in the Spinal Cord
Neuroplasticity
*Know for Exam! In Central Sensitization the Low Intensity Stimuli are Now suddenly causing pain due to Neuroplasticity- Very hard to Recover
Four Anticipated Complications of Ruminant Anesthesia
Hypersalivation- Adults Produce a lot of Saliva
Bloat- Leads to Decreased Venous Return and Hypoventilation
Hypoventilation- Be Prepared to Give IPPV
Regurgitation/Aspiration Pnuemonia- Secure the Airway Quickly to Prevent Aspiration Pneumonia- Intubate Swiftly and Inflate Cuff after Induction. Keep Head Elevated with Nose Pointed Down during Sedation and Recovery
Three Cardiovascular Pathologies that are Common and Generally Normal During Equine Anesthesia
2 Degree AV Block- Horses have Inherently High Vagal Tone
Wandering Pacemaker- Equine have Large SA Node
Biphasic P Wave
Drugs used for Premedication in Horses
Alpha 2 Agonists (Xylazine, Detomidine)- Most commonly used for Sedation, Muscle Relaxation and Analgesic Properties (Most Common Premedication for Horses). Detomidine has a Longer Onset but has a Longer Duration Duration as well
Acepromazine- Typically only Given in Excited Horses to Help with Sedation
*Opioids are Not commonly Administered as Premedication in Horses because we are getting Sedation from the Alpha 2 Agonists. Opioids can cause Excitment and COLIC in Horses
Drugs used for IV Induction in Horses
Ketamine + Benzodiazepine
Drugs used for Maintenance in Equine Anesthesia
In Hospital- Isoflurane/Sevoflurane
In Field- TIVA (Triple Drip)- Guaifenesin, Ketamine, Xylazine
*What Happens if Guaifenesin is Given With a Concentration Higher than 15%? Hemolysis will Occur (Moreso in Cattle- Greater than 6% Guafinesen will cause Hemolysis in Cattle)
Normal Heart Rate in BPM for Horses under General Anesthesia
30-45 BPM
Complication of Equine Anesthesia that can be caused by:
Decreased FiO2
Hypoventilation
V/Q Mismatch
Right to Left Shunt
Diffusion Impairment
Hypoxemia
*5 Causes of Hypoxemia Listed Above
*V/Q Mismatch is Very Common in Equine Species
Endotracheal Intubation is Difficult in Pigs because the Laryngotracheal Junction is at an _____ and the ETT can become Caught on the Floor of the Larynx
Angle
*Rotate the Tube 180 Degrees when it meets Resistance
Two Neuromuscular Blocking Agents can cause ____ Release leading to Vasodilation and Hypotension
Histamine
*Ex. Atracurium, Mivacurium
When Administering Neuromuscular Blocking Agents you must be certain to Provide ____ because Paralysis of Muscles of Respiration is Possible
Ventilation
Nondepolarizing Neuromuscular Blocking Agent that is Described Below:
Pancuronium
*Often leads to Tachycardia
Most Susceptible Nerves to Local Anesthetics
C Fibers, B Fibers, and A Delta Fibers
*A Delta and C Fibers are where Pain Transmission Occurs- They are Two of the Most susceptible Nerves to Local Anesthetics
*Least Susceptible- Motor FIbers. By Lowering the Concentration of Local Anesthetic we can Block Sensory but still Provide Adequate Motor Function
Oral NSAIDS Must be Given with ____ to Avoid Contact of NSAID Directly with Gastric Mucosa
Food
*With Food is a Must!! NSAID that Touches the Gastric Mucosa will cause Gastric Ulcers
Cardiovascular Drug that can be Used in the Treatment of Cardiopulmonary Arrest or Vasodilatory Shock
Vasopressin
*Decreases Tissue Perfusion- Significant Vasoconstriction
Which of these is Incorrect about Administering NSAIDS:
A. Select Patient Wisely
B. Use Highest Effective Dose
C. Monitor Patients Regularly with Long-Term Use
D. Avoid Concurrent NSAID or Corticosteroid Use
B. Use Highest Effective Dose
*NSAIDS- Use LOWEST Effective Dose
Did we Get an Artery? Yes (SO2 > 88%)
pH > 7.45 therefore Alkalosis
pCO2 is Low (Primary)
HCO3 is Low (Compensatory)
*Respiratory Alkalosis
PO2 is Low (Should be around 400-500 on 100% Oxygen)
BE- Normal (0 +/- 4)
Common Induction Drugs used in Ruminant Anesthesia
Telazol
Ketamine- Great for Cattle Inductions. Combine with Muscle Relaxant- Combine with Benzodiazepine or with Guafenisin (“Double Drip”)
Propofol- Used for Smaller Ruminants and Sheep
*Ketofol- Ketamine + Propofol IV Works well in Small Ruminants
During Ruminant Anesthesia Recovery, Leave ET Tube in Place until Strong Laryngeal Reflex Returns and Patient is able to remain ____. Immediately Check for Airway Patency after Extubation
Sternal
*In Ruminants- Pull the Endotracheal Tube INFLATED- DO NOT DEFLATE CUFF
*Check for Airway Patency- Obligate Nasal Breathers. Put Hands over Nostrils to feel Airflow
External Chest Compression Theory for Medium-Large Size Dogs where you Position your hands at the Widest Part of the Thorax where you use a Pressure Gradient to move Drugs forward
Thoracic Pump Theory
Part of the Pain Pathway where Sensory and Motor Action Potentials to and From the Spinal Cord are Carried by Peripheral Nerves, which are Categorized according to Size, Myelination, and Conduction Velocity
Transmission
*Afferent- Travelling Away from the Receptor towards the CNS
*Efferent- Signal Travelling back from the CNS to Create an Action (Ex. Move your Hand off Hot Plate)
We Cannot Give ____ Containing Fluid (Ex. Lactated Ringers) In the Same line as a Transfusion Product because it interferes with Anticoagulant and will make the Product Clot
Calcium
*We Also don’t want to Transfuse Hypotonic Fluid with our Transfusion Product because it will cause Hemolysis
Sally is a 1 y.o Intact Female Labrador Retriever that you are Perfoming an Ovariohysterectomy on at 8am and she will Stay in your Clinic Overnight. You will Check on her around 10pm for a walk and to Administer Pain Medications. What is your Preemptive Analgesia Plan?
*Always want to Make sure that if we are having a Painful Procedure you will Want an Opioid as part of the Neuroleptanalgesia Combination
*Used a Pure Mu (Morphine, Hydromorphone) because they are Much stronger Opioids
*Can an NSAID be administered before Surgery? Most Commonly only Given Post-operatively because you don’t want to compromise Kidney Blood Flow during Surgery
Which of the Following is Important when Selecting Patients for NSAIDS Administration?
A. > 6 Weeks Old
B. Well-Hydrated
C. Normal Hemostatic Function
D. No Concern or Evidence of GI Ulceration
E. Making Sure No Other NSAID has been given within 7 Days
F. All of the Above are important in Patient Selction for NSAIDS
F. All the Above are important in Patient Selection for NSAIDS
*Well-Hydrated- If we block Prostaglandin Production the kidneys cannot Autoregulate Blood Flow
Cystalloid Therapy that can be used in Patients with Emergency Acute Blood Loss that Draws fluid into the Intravascular Space and Improves Cardiovascular Function, however the Effects are SHORT-TERM
Hypertonic Saline (7.5% NaCl)
*With Every 1mL of Hypertonic Saline, Plasma Volume will Increase by 2-4mL
Bupivacaine
*Question on Exam
______ are Inidicated in Procedures such as:
Hind Limb Procedures
Femur Fractures
Pelvic Procedures
Stifle Procedures
Thoracotamy
Cranial Epidurals
*As you Inject More Volume of Epidural, the Drug can Move Further Cranially and Block areas of the Abdomen
*Don’t want the drug to Travel to far Cranially because it can Impair Diaphramatic Movements or cause Seizures in the Brain
Resuscitation Crystalloid Fluid that is used in Special Circumstances when your patient needs Increased Circulating Volume Quickly (Ex. Hemorrhage)
Hypertonic Saline
*Draws Fluid INTO Intravascular Space- Very Good for Emergency Situation where you need to Increase Circulating Volume
Nonselective COX Inhibitor Drug that Blocks COX 1 and COX 2 that is Formulated as a Tablet and can Lead to Side Effects such as GI Ulceration and Decreased Platelet Activity
Aspirin
Sally is a 1 y.o Intact Female Labrador Retriever that you are Perfoming an Ovariohysterectomy on at 8am and she will Stay in your Clinic Overnight. You will Check on her around 10pm for a walk and to Administer Pain Medications. What Type of Pain is Sally Experiencing Post-Op?
B. Epinephrine
Which Cardiovascular Drug has these Characteristics:
Non Specific Beta Agnoist
Increases Heart Contractility
Increases Heart Rate
Dobutamine
Peripheral Nerve Block that is Indicated in:
Declaws
Toe Amputations
Forefoot Block
*Injected into the Medial and Lateral Aspect of the Palmar and Dorsal Aspect of Each Limb, Just proximal to the Carpus
Technique for Eye Enucleation in Large Animals that Desensitizes the Oculomotor, Trochlear, Abducens and Trigeminal Nerves
Petersons Technique
*Peterson Technique Blocks the Eye but does not Block the Eyelids
Three Volume Replacement Options for Patients with Blood Loss
Crystalloid (
Colloid (10-20% Blood Loss)
Blood Products (> 20% Blood Loss)
*After 20% Blood Loss there is not enough Red Cells To Carry Oxygen to Tissues so we must use a Blood Product, usually either Packed Red Cells or Whole Blood- Carry Oxygen
Where are the ECG Leads Placed during Ruminant Anesthesia?
Base-Apex
Review of Four Primary Disturbances and Expected Compensatory Responses
Primaries are in Red!
Think of Bicarb (HCO3) as a Base causing Alkalosis
Think of CO2 as an Acid causing Acidosis
Metabolic Acidosis- Decreased pH, Decreased Bicarbonate, Compensatory Decrease in CO2
Metabolic Alkalosis- Increased pH, Increased Bicarbonate, Compensatory Increased CO2
Respiratory Acidosis- Decreased pH, Increased CO2, Compensatory Increased Bicarbonate (common in Anesthetized Patients)
Respiratory Alkalosis- Increased pH, Decreased CO2, Compensatory Decreased Bicarbonate
Nonselective COX Inhibitor Drug that is used in Horses and Cattle and Can be Formulated as a Powder, Paste or Parenteral that has a Duration of 12 Hours but there is a HIGH Risk of GI Ulceration
Phenylbutazone
*High Risk of GI Ulceration and Nephrotoxicity
Peripheral Nerve Block in Large Animals that Provides Anesthesia of the Upper Lip and Nose for Suturing of Nasal Laceration or Placement of Nose Ring in Cattle
Infraorbital Nerve Block
*Desensitizes the Area that you Inject and Rostrally
True/False: In an Animal with Infectious Disease you should Avoid Administering Local Anesthetics
True
*Infections create more Acidic Environments, causing the pH of Drugs to Drop Dramatically. The Local Anesthetics pH will be Further from Tissue pH leading to a longer onset of action
*Less Drug will be able to Penetrate into the Nerve due to Slower Onset, leading to Higher Systemic Absorption- Be cautious when Injecting a Local Anesthetic into an Area that is Infected because you may see more Systemic Absorption and Toxic Side Effects
A. pKa 7.5
Indications for ____ Transfusion:
Coagulopathies
Fresh Frozen Plasma
*If you have a Patient that Needs Clotting Factors- Ex. Rodenticide Toxicity, Hepatic Failure, or DIC
Patient is Experiencing Supraventricular Tachycardia. What Drugs can be Used to Slow Down the Heart?
Beta-Blockers (Ex. Esmolol or Diltiazem)
*Esmolol is Commonly used to Slow Down the Heart!
Motor Fibers- Least Susceptable to Local Anesthetics- Last to be Blocked
*By Using a Lower Concentration of Local Anesthetics you are less likely to Impair Motor Function
Examples of Replacement _____ Include:
Normal Saline
LRS
Normasol- R
Pl-A
Pl-128
Crystalloids
During Equine Anesthesia Recovery the patient should be Discouraged from Standing when ____ is still Present
Nystagmus
*Nystagmus occurs in Stage II Anesthesia
Blood Volume = _____ + Erythrocytes
Plasma
*Need to Know these Numbers on Exam
Ex. 20 kg Dog. What is its Total Blood Volume? (20 x 90 = 1800)
Cardiovascular Drug that is a Beta Agonist for the Treatment of Hypotension in Equine Patients
Dobutamine
Fasting is Controversial in _____ and Generally you Withhold Food 3-6 Hours so the Patient is not Overly Stressed
Equines
*Do NOT Fast Foals
*When Preping Horses for Anesthesia we Flush Food Debris out of the Mouth because when we Intubate we don’t want to Push anything down into the Lungs
Arterial Samples are used to Evaluate _____ Gas Exchange and the Patients Oxygenation Status
Respiratory
*Arterial Blood Gas- Determine Oxygenation Status
*Venous Sample- Deoxygenated Blood so it Cannot tell you anything about the Patients Oxygenation Status
During Ruminant Anesthesia, Keep the Head and Neck Elevated and Patient in ____ Recumbancy after a Premedication is Given
Sternal
_____ Can be Given in Large Volumes to Expand Extracellular Fluid Volume Without Changes in Electrolyte Composition, Thus Does NOT Induce Fluid Shifts between ICF and ECF
Cystalloids
Two Peripheral Nerve Blocks that can be Used for TPLO’s and Crutiate Repairs
Femoral Nerve Block
Sciatic Nerve Block
Part of the Pain Pathway with Integration, Processing and Recognition of Sensory Input that Occurs in Multiple Areas of the Brain, which Communicate by Interneurons to produce a coordinated Response in the Body
Perception
The Peri-anesthetic Fluid Rate is _____mL/kg/h for Most Cases. For Cats, the Peri-anesthetic Fluid Rate is ____ mL/kg/h
10 mL/kg/h
5 mL/kg/h
*Cats have a Smaller Blood Volume so they don’t require as much fluid and they are more Prone Over Hydration
Cyclocoxygenase ____ is:
INDUCIBLE
Upregulated during Inflammation (20x’s Normal Concentration)
Key Role in Nociception
Involved in Constitutive Functions with COX 1
Cyclooxygenase 2 (COX 2)
*COX 2 is and INDUCIBLE Situation. During inflammation there is 20x’s more COX 2 in the Tissue than you would in a normal State
The Following are Commonly used_____ Fluids:
Hetastarch (Hydroxy-ethyl Startches)
Albumin
Dextrans
Colloid
Is this Arterial? Yes (SO2 > 88%)
pH is Acidemic
pCO2 is High (Primary)
PO2- Normal
_*Respiratory Acidosis- Severely Hypoventilating_
HCO3 (Bicarb)- High (Compensatory)
BE- Normal
Premedications used for Pig Anesthesia
Alpha 2 Agonists (Xylazine)- Effective when Combined with Ketamine +/- Opioid
True/False: Neuromuscular Blocking Agents Provide No Sedation, Anesthesia or Analgesia, therefore Adequate Anesthesia and Analgesia must be provided when Administering Neuromuscular Blockers
True
*Inhumane when used as Sole Agent
Which Vein is Used when Placing an IV Catheter for Ruminant Anesthesia?
Jugular Vein
*Accessed Most Easily during Surgery- Use a Large Gauge Catheter!
Impedence Device
*Creates Negative Pressure in the Thorax
____ of Extra Cellular Fluid is INTRAVASCULAR
1/4
*Interstitial Fluid makes up 3/4 of ECF
*Intravascular Fluid makes up 1/4 of ECF
Most of the ECF is in the Intersitial Compartment or Intravascular Space. The Only Place we can Affect Quickly is the Intravascular Space
Treatment of Anesthetic Induced Hypotension
5-10 mL/kg over 15 Minutes
*Give Hourly Crystalloid as Rapid Bolus. When we Give a Fluid Bolus Under Anesthesia, we give our Hourly Rate in 15 Minutes
*You DO NOT give the Shock Rate fluid Bolus in this Situation
Topical Anesthetic Sprayed on Arytenoids to Prevent Laryngeal Spasm during Intubation
Lidocaine Spray
Peri-Anesthetic Fluid Type used in these Situations:
Correct Hypovolemia
Hypoproteinemic Patients
Support Colloid Osmotic Pressure
Colloids
*Corrects Hypovolemia- Colloids stay in the Intravascular Space
Hypoproteinemic Patients- Colloids Prevent Edema and Fluid Shifts
If you have a Patient with Total Protein
Nondepolarizing Neuromuscular Blocking Agent that is Described Below:
Vecuronium
COX Preferential NSAID Drug that is used in Dogs, Cats, Horses and Cattle with a Duration of Action between 12-48 Hours with Side Effects Including Vomiting, Diarrhea, Hepatic and Renal Issues
Meloxicam
Normal Heart and Pulse Rate in Adult Cattle and Calves, sheep, and Goats
Commonly used Opioid given for Analgesia in Ruminant Anesthesia
Butorphanol
True/False: Local Anesthetics that are more Likely to have Protein Binding tend to Increase the Duration of Action of the Drug
True
*Bupivacaine has 95% Protein Binding- More Likely to have Longer Duration of Action
COX 3 Preferential NSAID that is NOT approved for Veterinary Patients, but is used in Dogs, with Side Effects Including HEPATIC Damage
Acetaminophen
*NOT FOR USE IN CATS- Heinz Body Anemia
Peripheral Nerve Block that Desensitizes Ipsilateral Incisors, Canine Tooth, Premolars and Molars as well as the Skin and Mucosa of the Chin and Lower Lip
Mandibular Nerve Block
Review of Lung Volume and Capacity
*Understand these Different Lung Volumes and Capacities- KNOW
Tidal Volume- Normal Breath In and Out
*Tidal Volume + Inspiratory Reserve Volume = Inspiratory Capacity
*Tidal Volume + Expiration Reserve Volume = Expiration Capacity
*Tidal Volume + Inspiratory Reserve + Expiratory Reserve = Vital Capacity
_____ Occurs with Rapid, Continous Firing of Primary Nociceptive Afferents, Especially C Fibers, which Stimulates the Release of Increased Amounts of Glutamate, Substance P, and BDNF leading Upregulation
Windup
*General Anesthesia does NOT prevent Windup since it does not prevent the Generation of Action Potientials in the Primary Afferents
When Performing Cranial Epidurals in Felines, the ____ ends Close to L7-S1 and we are More likely to Penetrate the ____
Dural Sac
*The Cats Dural Sac may end closer to L7-S1 and if you accidently Puncture that Dural Sac, the Drug will Travel straight to the Cats Brain
*Decrease Dose by 1/2 if CSF is Obtained
Sensory Nerves that Have a _____ Firing Rate are More Susceptible to Local Anesthetics
Higher
In Large Animals, Local Anesthesia of the ____ can be done by:
Inverted L Block
Incisional Block
Epidural
Proximal Paravertebral Block
Distal Peravertebral Block
Flank
*Incisional Block- Giving Local Anesthetic in the Area of Incision
*Epidural- Can be used for Abdominal Procedures so long as you give enough Volume
*Nerve Roots that Come Directly out from the Spinal Cord you can Desensitize them either Proximally or Distally to provide adequate Analgesia to the side that is being Innervated
Peripheral Nerve Block that Desensitizes Rostral Mandible and Ipsilateral Canine and Incisors
Mental Nerve Block
True/False: Highly Perfused Areas have a Shorter Duration of Action with Local Anesthetics, and Poorly Perfused Areas have a Much Longer Duration of Action with Local Anesthetics
True
*Highly Perfused Areas have Faster Systemic Absorption, and Therefore Shorter Duration of Action
*Poorly Perfused Areas have a Much Longer Duration of Action
Fluid Therapy used in Patients that have Massive Hemorrhage and you need to Move Fluid into the Intravascular Space, where Results are Short-Term and must be follwed by either Cystalloid or Colloid if Hypovolemic
Hypertonic Saline
Best Place to do IM Injections for Pig Anesthesia
Neck Area Caudal to the Ear
*Do Not want to Place IM Injections in the Hind Area of Pigs
Peripheral Nerve Block that is Used in Horses and Cattle for Examination of the Eye, that DOES NOT Desensitize the Eyelids
Auriculopalpebral Block
*Stops the Animal from Blinking when you are doing the exam (Paralysis), but does not Desensitize the Eyelids
Condition in Pigs that is most Prevalent in Individuals with High Ratio of Muscle to Total Body Mass caused by a mutation in the Porcine Ryanodine Receptor 1 gene that leads to Rapidly Increasing ETCO2
Malignant Hyperthermia
*Most Diagnostic Clinical Sign- Rapidly Increasing ETCO2
*100% Mortality Rate- If occurs during Anesthesia then Rapid Termination of Inhalant and Body Cooling may be helpful
Which Cardiovascular Drug has these Effects Below
Epinephrine
*May decrease Renal Blood Flow because it causes such Massive Vasoconstriction
A. Methadone
C. Cardiovascular Depression
NSAIDS Have a Very ____ Safety Margin, therefore we NEVER Exceed the Upper Dose Limit
Narrow
*One of the Most common Drugs we Perscribe but one of the Least Safe
*Use the Lowest Effective Dose
*You Must Wash Out NSAIDS- Discontinue with no NSAIDS for a 7 day Period of Time before you restart a new NSAID- WE DO NO MIX NSAIDS WITHIN 7 DAYS- KNOW THIS
Treatment of Hyperkalemia in Equine Patients
Calcium Gluconate- Does not Lower Serum Potassium Level, it just Stabilizes the Myocardium
0.9%NaCl (Saline)- Dilutes Down the Potassium Level
All of the Following are Contraindication to ____ Use:
Acute Renal Insufficiency
Hepatic Insufficiency
Dehydration
Hypotension/Hypovolemia
Coagulopathies
GI Ulceration
NSAIDS
*The Use of Other NSAIDS or Corticosteroids are also Contraindications- If the Patient is On Other NSAIDS or Corticosteroids you CANNOT Give them a different NSAID for 7 days!!!
*Acute Renal Insufficiency- If you inhibit Prostaglandins the Kidneys cannot Autoregulate Blood flow and Nephrons will Die!
*Hepatic Insufficiency- NSAIDS are Metabolized by the Liver
Review of Nerve Fibers
Two Fibers Involved in Pain- C Fibers and A Delta
*C Fibers are Unmyelinated- Slow Conduction Velocity
Degree of Myelination shows how fast the Conduction Velocity is- More Myelination, means Faster Velocity
Which One of these is Incorrect for Performing Chest Compressions:
A. Place Patient on Soft Surface
B. R,L Lateral Recumbancy
C. Change People Every 2 Minutes
D. 80-100 Compressions per Minute
E. Compress Chest 30%, Allow Full Recoil
F. CONTINOUS compressions
A. Place Patient on Soft Surface
*We want to Place the Patient on a Firm Surface because you don’t want any give
*Change People every 2 Minutes- Providing good Chest Compressions is Physically Exhausting
*Compress Chest 30%, then allow full Recoil- During Recoil is when Venous Return Occurs so you don’t want any pressure on the chest during Recoil
True/False: Type and Crossmatch must be Performed prior to Every Whole Blood, RBC, or Plasma Transfusion in Felines
True
Many Anesthetic Drugs are Highly Protein Bound. If a Patient has ______ the Anesthetic Drugs will have a more Profound Effect
Hypoproteinemia
*We Cut Down our Drug Doses in Hypoproteinemic Animals if we know the Drug is Highly Protein Bound- More Free Drug when Proteins Levels are Low = More Profound Effects
*Without Proteins in the Vascular Space pulling Water in, the Vessels will become Leaky and lead to Edema and Hypotension
Infraorbital Nerve Block Desensitizes _______ Adjacent to Injection and Rostrally
Upper Dental Arcade
*Blocks Nerve Fibers where you Inject and then Rostrally
*Anything Behind where you Inject Local Anesthetics in the Infraorbital Foramen will NOT be Desensitized
*Infraorbital Nerve Block- Not Useful for Molar Extraction- Molars are Behind the Infraorbital Foramen
Pain Scale based on Specific Behavoiral Signs believed to Represent Pain in the Dog that has One Physiologic and Seven Behavoiral Categories
The Glasgow Composite Measure Pain Score (GCMPS)
_*Better Scale- Has been Validated by Statistical Method_s
_____ are Not Used in Ruminants because Salivary Secretions will become more Viscous and Could Obstruct the Airway
Anticholinergics
135mL
(15kg x 90ml/kg) x .10 = 135mL
Review Card
*Aceytlcholine Binding is Competitive and Reversible
*If you have more Ach than NMBA, then Muscle Contraction will Occur
*If you have More NMBA than Ach, then Muscle Paralysis will Occur
Review of Ocular Rotation under Cattle Anesthesia (KNOW THIS)
Light Anesthesia- Palpebral Reflex Disappears
Induction- Eye Rotates Ventrally and Partially Obscured Cornea
Deepening Anesthesia- Pupil Hidden by Lower Lid
Deeper Anesthesia- Dorsal Rotation of Eyelid (Too Deep)
*Rotation of Globe does NOT occur Under Anesthesia in Sheep and Goats
Electric Shock that Depolarizes Myocardial Cells used Only on Patients with Ventricular Fibrillation and Pulse-less Ventricular Tachycardia
Defibrillation
*After Defibrillation you have to Restart Compressions for At least 2 more Minutes. You’re Depolarizing the Heart and it takes time to Repolarize
Lipid Solubility is Positvely Related to Potency of Local Anesthetics. As Lipid Solubility ______, Potency Increases
Increases
*Drugs that are More Lipid Soluble Facilitate Nerve Penetration more Readily and Absorbs into the Myelin Sheath leading to a Slower Onset and Longer Duration of Action
*Highly Lipid Soluble drugs are Absorbed into the Myelin Sheath, which does not Block the Nerve, Leading to Slower Onset and Longer Duration
COX 2 Selective NSAID that is used in Dogs and Formulated as a Tablet with a Duration of 24 Hours and Side Effects including Vomiting/Diarrhea, Hematochezia, and Melena
Deracoxib
Local Anesthetic Duration of Action is based on Protein Binding. The Greater the Protein Binding, the _____ the Duration of Action
Longer
Sally is a 1 y.o Intact Female Labrador Retriever that you are Perfoming an Ovariohysterectomy on at 8am and she will Stay in your Clinic Overnight. You will Check on her around 10pm for a walk and to Administer Pain Medications. What is your Postoperative Analgesia Plan?
*Carprofen- NSAID given for post operative Pain Managment
*Buprenorphine (Opioid) can be Given for Moderate Pain- Less Side Effects with Buprenorphine than Morphine
Calculate the Drip Rate in Drops/Second
1 Drop/Second
*(20 kg x 10 mL/kg/h x 20 Drops/mL)/ 60 Seconds
We _____ Ruminants during Anesthesia to Prevent Aspiration of Salivary Secretions or Rumen Contents if Regurgitation Occurs
Intubate
Review of Adrenergic Agonists (Cardiovascular Drugs)
*Drugs that Act on Beta 1 will I_ncrease Contractility_
*Drugs that act on Alpha will Increase Vasoconstriction
*Drugs that Act on Beta 2 will I_ncrease Vasodilation_
An adrenergic agonist is a drug that stimulates a response from the adrenergic receptors. The five main categories of adrenergic receptors are: α1, α2, β1, β2,
Commonly used Premedications for Ruminant Anesthesia
Acepromazine- Administered IM in Neck
Xylazine- More Potent in Ruminants (Use 1/10th of the Equine IV Dose)
*These Drugs are Not approved for use in Food Animals but they are used Off Label
Sensory Nerves have a ____ Diameter with a Higher Firing Rate, Therefore they Block Earlier and with a Lower Concentration of Local Anesthetics
Smaller
*If the Surgeon is Concerned with Motor Function, you can Find ways to Provide Adequate Motor Function while Blocking Sensory Nerves because Sensory Nerves are More Sensitive to Local Anesthetics and will be Blocked before Motor Nerves
Technique for Local Anesthesia of the Flank where you Administer the Local Anesthetic Between T13-L1, L1-L2, and L2-L3
Proximal Paravertebral
*Desensitizes the Entire Flank
*Advantages: Wide and Uniform Area of Analgesia and Muscle Relaxation, Faster Technique
*Disadvantages: Difficult in Obese Cattle, Possible Scoliosis, Risk of Hitting Aorta or Vena Cava
The Percentage of all Available Heme-Binding Sites Saturated with Oxygen from an Arterial Sample is a Calculated Value based on the Position on the Oxygen Hemoglobin Dissociation Curve and PaO2
SaO2 (Saturated Oxygen)
*At 80mmHg and 95% SaO2 - Mild Hypoxemia
*At 60mmHg and 90% SaO2- Severly Hypoxemic
Which Cardiovascular Drug is Described Below?
Dopamine
*Increased Contractility- Beta 1 Agonist
*Only when Using High Dose of Dopamine, will cause Vasoconstriction
Important Complication of Equine Anesthesia
Hypotension
*Hypotension can lead to Postanesthetic Myopathies in Horses
*If the MAP is Kept > 70mmHg Post Anesthetic Myopathies do not commonly occur. Keep MAP > 70 mmHg
Review of Plasma Volumes and Blood Volumes in Species
*Know the Blood Volume by Species- So that you can Calculate How Significant Blood Losses are going to be and how aggressive your Treatment needs to be
Blood Sample was Taken and the pH is 7.23 Is this Patient Acidemic or Alkalemic?
Acidemia
*Normal pH = 7.4
Indicated Peripheral Nerve Block used for Extraction of an Incisor, Canine, and Molar all on the Same Side
Maxillary Nerve Block
Review Card
Arterial: (Rule of 4’s)
pH- 7.4
PaCO2- 40mmHg
PaO2- 100mmHg (Room Air); 400-500mmHg (100% Oxygen)
HCO3- 24 mmol/L
BE- 0 +/- 4 mmol/L (Ideal BE is Zero)
SaO2- 95-100%
Lactate
Nonselective COX 1 and COX 2 Inhibitor Drug used in Horses and Ruminants that can be formulated as Granules, Paste or Parenteral with Side Effects Including Local Swelling and GI Ulceration
Flunixin Meglumine
Review Card- Will be on Exam
*Guidelines for IPPV
Tidal Volume- Know 10-20 mL/kg in Small Animals
*I:E Ratio- 1:2-1:3. Ex. If you spent 2 Seconds in Inspiration, how many Seconds would you want to spend in Expiration? 4-6 Seconds
You want to Spend LONGER in the Expiration Phase than the Inspiration Phase- Want to give the body time to have the venous Return
*Peak Inspiratory Pressure (PIP)- When you Deliver a Breath, you want the Pressure Guage to stay around 20 cm H20 in small animals
Inhalant Anesthetics Alter the Distribution of Pulmonary Blood Flow in Horses, Resulting in Areas that are Perfused but not well Ventilated, which Worsens Hypoxemia by Contributing to ______
V/Q Mismatch
*V = Ventilation
Q = Perfusion
Commonly Used Nondepolarizing Neuromuscular Blocking Agent that is Described Below:
Atracurium
*Repeated Doses are Not Cumulative
*Hofmann Eliminiation- Spontaneous Molecular Decomposition
*Good for Patients with Renal and Hepatic Disease because half of it has Breakdown that doesn’t Rely on Functioning Kidney or Liver
*Atracurium = Histamine Release
Acute Blood Loss > 20% Means the Patients PCV will be
*Need a Minimum Hemoglobin of 7mg/dL (PCV 21%) for Oxygen to be Delivered to Tissues. If PCV is Below 21%, Oxygen will not be Delivered to Tissues- Consider a Blood Transfusion
Cardiovascular Drug that is an Alpha 1,2 and Beta 1,2 Agonist which is the Strongest Vasopressor and Administered during Cardiopulmonary Arrest
Epinephrine
*I_ncreases Heart Rate_ due to Strong Beta effects
*Generally Causes Vasoconstriction- If a Drug has Alpha Effects, generally the Alpha Effects will Predominate the Beta Effects, in this case causing Vasoconstriction
Name the 5 Parts of the Pain Pathway (Nociception)
1. Transduction
2. Transmission
3. Modulation
4. Projection
5. Perception
*Ex. We get a Cut and we Transduce that Signal. The Signal will be Transmitted along those Nerve Fibers to the Grey Matter Dorsal Horn. Modulation Occurs in the Dorsal Horn and is Projected up to our Brain, which is able to Perceive the Signal
Local Anesthetic with the Highest Protein Binding and Highest Lipid Solubility (Potency) and therefore the Longest Duration of Action
Bupivacaine
Drug that works on V1A and V2 Receptors to cause Significant Vasoconstriction and is Effective in Acidic Environments
Vasopressin
*Effective in Acidic Environments. Epinephrine does not work once your patients become Acidemic. If we are Worried the Patient is Acidemic, we will Start with Vasopressin rather than Epinephrine
Indications for ____ Transfusion:
Acute Blood Loss/Hemorrhage
Anemia
Whole Blood
Nondepolarizing Neuromuscular Blocking Agents that Bind NAchR withOUT Activating it leading to FLACID Paralysis
These Drugs lead to FLACID Paralysis
Local Anesthetic with the Longest Duration of Action
Bupivacaine
*Bupivacaine is 95% Protein Bound
More Protein Bound = Longer Duration of Action
*Lidocaine has the Fastest Onset of Action, while Bupivacaine has the Longest Duration of Action!
*He Prefers Bupivacaine for Procedures because he wants the Local Anesthetic to Last longer and Provide more Analgesia
In Arterial Samples the PaO2 will be _____mmHg on Room Air or ______ if on 100% Oxygen (Anesthetized Patients)
80-110 mmHg
500 mmHg
*SaO2 (Saturated Oxygen) > 88%
*Arterial Sample- Pulsatile Flow
If Using a DEA (___) Donor, Type and Crossmatch is NOT Performed on 1st Transfusion
(–)
*Type and Crossmatch Any Transfusion given > 5 Days after Initial Transfusion
1st Priority Resuscitation Drug in a Full Cardiopulmonary Arrest
Epinephrine
*Acts on Alpha and Beta Receptors- Causes Intense Peripheral Vascoconstriction that Centralizes our Blood Volume
*Dose to use: 0.01 mg/kg IV
Common Nerve block for Eye Enucleation in Large Animals where you Aspirate Local Anesthetics into the Back of the Eye
Retrobulbar Block
Number 1 Priority in Cases of Cardiopulmonary Arrest that is Done to Pump Blood from the Chest to Vital Organs in order to Maximize Cerebral and Myocardial Perfusion
Continuous Uninterrupted Chest Compressions
*Even if only 1 Person is There- Do not Try to get an Airway, start Chest Compressions immediately and DO NOT STOP
*Venous Return occurs during Relaxation
Nociceptor that is High Threshold, takes a stronger stimulus to Activate, that Responds to Cold Temperature, Burning and Freezing (“Slow Pain”)
C-Fiber
*C Fibers- Unmyelinated- Takes Longer to Transmit the Pain Signals
Which Cardiovascular Drug does this Describe?
Norepinephrine
*Does not as Significantly Increase the Heart Rate compared to Epinephrine
Crystalloids Redistribute Quickly, where Only _____% Remains Intravascular 15 Minutes after Infusion
20-30%
*15 Minutes After Injection, 2/3rds to 3/4ths of the Cystalloid you gave is gone from the Intravascular space and Moved into the Interstitium
*For Every 1mL of Blood Loss you’re going to give 3-4mL of Crystalloid because only 20-30% of it stays in the Vascular Space
Technique for Local Anesthesia of the Flank, where you Administer Two Injections (Dorsal and Ventral) of Local Anesthetic at L1, L2, and L4
Distal Paravertebral
*Don’t Inject at L3
*Advantages: Lack of Scoliosis, Lack of Risk of Penetrating Major Blood Vessels
*Disadvantages: Larger Doses of Anesthetic
Respiratory Acidosis
True/False: Rotation of the Globe Occurs Under Anesthesia in Sheep and Goats
False
In Canine Blood Transfusions, Only DEA (___) Dogs should receive DEA (___) Donor Blood to Prevent DEA Sensitization of a DEA (–) Dog
(+)
*DEA = Dog Erythrocyte Antigen. It Important that if you have a DEA (+) Dog they can get a DEA (+) or (-) Transfusion. If you have a DEA (–) Dog, They can Only Recieve DEA (–) Blood- You don’t want to introduce them to the Antigen
Use DEA (–) Donors- Can Donate to Both DEA (+) and (-) Dogs
No Need to Test for Plasma Tranfusions, Just Whole Blood and RBC if not a “Transfusion Virgin”
____ Epidurals are used for Surgical Procedures in Horses and Cattle that involve the Tail, Perineum, Anus, Rectum, Vulva, Prepuce and Skin of Scrotum
Caudal
*Gray Areas show where Desensitization will Occur. Caudal Epidurals do not affect the Hind Legs and most of the time you will do and Epidural in a Standing Horse
Dose of Cystalloids used when Giving Fluid Therapy to a Patient in Cardiopulmonary Arrest that is Hypovolemic
Shock Doses: 90 ml/kg in Dogs, 45 ml/kg in Cats
Drug that is Indicated for use in a VAGALLY Induced Cardiopulmonary Arrest
Atropine
*Under Anesthesia, almost all Anesthesia Arrests Get Atropine because the Patients have High Vagal tone under Anesthesia
Peripheral Nerve Block that Desensitizes Ipsilateral Upper Dental Arcarde and Maxilla
Maxillary Nerve Block
*Desensitizes All the Teeth in the Upper Arcarde on the Side of Injection
*Indications- Molar Extraction
When Assessing the Anesthetic Depth in Horses the _____ Signs are Very Important- Palpebral and Corneal Reflexes, Lacrimation, Nystagmus, and Position of the Eyeball
Eye Signs
*Blinking, Lacrimation (Watery Eyes) and Nystagmus are all Signs that the Horse is Too Light
*Drug that makes the Reflexes Less Reliable- Ketamine
Nociceptor that has Low and High Threshold that Responds to Hot Temperature, Sharp, Pricking, Burning, and Freezing (“Fast Pain”)
A Delta Fibers
Vasodilation
Contractility
Bradycardia
Infiltration Technique used for a Flank Approach in Cattle, where we Desensitive the Nerve Fibers against the Caudal Border of Rib 13, just Ventral to the Lateral Processes of the Lumbar Vertebrae
Inverted L
Peripheral Nerve Block that Desensitizes:
Upper Dental Arcade (Adjacent to Injection and Rostrally)
Upper Lip and Nose
Dorsal Aspect of Nasal Cavity
Soft and Hard Palates
Infraorbital Nerve Block
*Does NOT Desensitize Anything Behind the Infraorbital Foramen
Most Common Arteries to Obtain Blood Gas Samples in Large Animals
Blood Sample was Taken and the SaO2 is > 88%. Is this a Venous or Arterial Sample?
Arterial
Peripheral Nerve Block used in Large Animals to Desensitize the Eye and Allow for Sufficient Opthalmic Examination
Supraorbital Nerve Block
*Anesthesia to the Upper Eyelid- Desensitizes
*If you have a Laceration to the Upper Eyelid you should do an Auriculopalpebral Block to Stop Blinking and a Supraorbital Block to Desensitize the Eyelid
Two Main Nerve Fibers that are Involved with Pain
A Delta
C Fibers
Three Drugs that can be Given to Reverse Nondepolarizing Neuromuscular Blocking Agents
Anticholinesterase Drugs:
Edrophonium
Neostigmine
Pyridostigmine
*These Three Drugs Increase Acetylcholine at the Neuromuscular Junction
Cardiovascular Drug that is an Alpha 1 Agonist that Causes:
Significant Vasoconstriction
Splenic Contraction
Decrease Epistaxis
Decrease Nasal Edema (Nasal Decongestant)
Phenylephrine
*Allows Patients to Breath much better through their Nose- Nasal Decongestant
*Phenylephrine may be Useful in Patients in Shock with Severe Vasodilation. Phenylephrine can be Given to Help bring Blood Vessels back to a normal Size
For Patients in Cardiopulmonary Arrest that has Lost Greater than 10% of its Blood Volume, Which Fluid should we use in Fluid Therapy?
Colloids
What Oxygen Flow Rates are used during Ruminant Anesthesia? Which Inhalant Anesthetic is most Cost Effective in Ruminant Anesthesia?
10-20 ml/kg/min
Isoflurane
Two Sensory Nerves Targeted by Local Anesthetics
A (Delta) and C Fibers
True/False: In a Cow you need to Block One Nerve for Dehorning, while in a Goat you need to block Two Nerves for Dehorning
True
*Cattle- Block Cornual Branch of Zygomaticotemporal
*Goat- Block Cornual branch of Infratrochlear and Cornual Branch of Zygomaticotemporal
IV Access in Equines is done with a _____ Catheter placed in the Side of the Neck that will be “up” if Placed in Lateral Position
Jugular
