Week 6 notes Flashcards
local analgesia does what?
blocks pain transmission
When is local anesthesia utilized?
when patient is easy to handle, general anesthesia is undesirable or high risk, and means to deliver general anesthesia safely is unavailable.
What are the advantages of local anesthesia?
Low cardiovascular toxicity, low cost, excellent pain control in the immediate postoperative period, and minimal patient recovery time.
What determines local vs. general anesthesia?
DVM’s choice, temperament, age, species, physical status, cost, nature of procedure, and anesthetists skill.
What are the local anesthetic agents we use?
Lidocaine, bupivacaine, mepivacaine, procaine, tetracaine, and proparacaine.
what are the most commonly used local anesthetics?
Lidocaine and bupivacaine
what %’s of Lidocaine do we use?
0.5 - 2
What do we mix Lidocaine and bupivacaine with to dilute?
sterile saline
Where does general anesthesia primarily effect the body?
primarily the neurons in the brain
Where do local anesthetics exert their effect on the body?
exert effect on the neurons in the peripheral nervous system and spinal cord
Local anesthetics are made useless by what?
fat, bone, cartilage, fascia, tendons, and inflammation and infection
MoA of local anesthetics?
blockade of sodium channels, neurons can not generate electrical impulses, absorbed into local circulation and metabolized by the liver
administration of local anesthetics may cause temporary?
paresis and paralysis
what is ethyl chloride used for?
skin biopsies and superficial procedures
what does eutectic mixture do? and what is it?
ELMA cream, mixture of 2.5% Lidocaine and 2.5% prilocaine. desensitizes intact skin for superficial minor procedures (catheterization)
where is a splash block used and what caution should you take when using it?
utilized in wounds and/or open surgical sites. use caution to avoid overdose
What are the maximum dosages for splash blocks for cats and dogs with Lidocaine and bupivacaine?
Lidocaine- cats ( 2mg/kg), dogs (4 mg/kg)
Bupivacaine- cats (0.5 mg/kg), dogs (2 mg/kg)
what does infiltration route mean with local anesthetics?
injected into tissues in proximity to the target nerve
What drug is most commonly used for filtration?
Lidocaine
epinephrine + local anesthetic causes what?
constriction of blood vessels in the area of infiltration and prolongs the effect of Lidocaine by 50%
Lidocaine + epinephrine should not be used when?
incision site, ears, digits, and tails
epinephrine increases the risk of what?
ventricular arrhythmias
what is the CRI dose of Lidocaine for dogs and horses? cats?
50-75 mcg/kg/min dog/horse, 25 mcg/kg/min cats
What are some clinical situations to utilize nerve blocks?
lameness exam on a horse, dehorning cattle, dental blocks, chest surgery, amputation, and declawing
What is a line block?
continuous line of local anesthetic placed in subcuticular tissues immediately proximal to the target area
Line blocks are positioned where?
between the target area and the spinal cord
What is a ring block?
line of local anesthetic completely encircles an anatomic part
Line and ring blocks are used exclusively in what?
equine and food animal surgery
What are some advantages of regional anesthesia?
wide, uniform area of anesthesia, shorter time required to perform block
disadvantages of regional anesthesia?
technical skill required, hind limb weakness, and scoliosis
Epidural anesthesia blocks sensation and motor control of the ?
rear, abdomen, pelvis, tail, pelvic limbs, and perineum
Epidurals are most commonly used in what patients?
Ruminants, debilitated small animals, and patients requiring profound pain control post surgically
What are the drugs of choice for epidurals?
2% Lidocaine, 0.5% bupivacaine, morphine, and combinations (opioids and alpha 2 agonists)
What are some adverse effects of local anesthetics?
loss of voluntary motor control of affected body part, temporary or permanent loss of nerve function, tissue irritation, paresthesia, allergic reactions, systemic toxicity, spinal cord trauma, infiltration of the caudal spinal cord, and diffusion of anesthetic into the cervical and thoracic spinal cord
Pain is?
unpleasant sensory or emotional experience associated with actual or potential tissue damage
analgesia is?
the absence of the awareness of pain, achieved through the use of drugs or other modes of therapy
Technicians must know what 5 principles of analgesia?
ensure analgesia is provided for every patient requiring it, recognize procedures likely to be painful, use techniques to minimize pain, monitor behavior and physiologic variables as potential indicators or pain, must bring animals requiring analgesia to the vet’s attention
Untreated pain can negatively affect a patient’s ?
behavior, physiology, metabolism, and immune system
What is your goal as a technician for animal pain?
provide adequate analgesia and sedation to allow your patients without undue discomfort to move, eat, sleep for 12 to 24 hours after surgery
pain results when ?
nerve cells (nociceptors) in the skin or deep tissues detect noxious stimuli
What are the types of pain and explain?
physiologic pain- ouch pain pathologic pain- broken bone neuropathic pain- nerve pain visceral pain- organ pain somatic pain- musculoskeletal pain idiopathic pain- no identifiable cause
What are the chemicals released by inflammation or tissue damage?
prostaglandins, leukotrienes, bradykinin, proteolytic enzymes, histamine, potassium ions, serotonin
what are the 3 pain stimuli’s?
chemical stimuli, thermal stimuli, mechanical stimuli
What are the two types of sensory neurons?
A delta fibers and c fibers
A delta fibers transmit ?
sharp, discrete pain signals
C fibers transmit ?
dull, aching or throbbing pain signals
How do we classify pain?
mild, moderate or severe
What are the behavioral responses to pain for dogs?
vocalization, facial expressions, body posture, guarding, self-mutilation, activity, attitude, appetite, urinary/bowel habits, grooming, response to palpation
what are the behavioral responses to pain for cats?
vocalization, facial expression, body posture, guarding, self-mutilation, activity, attitude, appetite, urinary/bowel habits, grooming, and response to palpation
What are some methods of pain control?
acupuncture, massage therapy, magnetic therapy, hot and cold therapy.
what some things that go with conscientious nursing care?
comfortable bedding, quiet surroundings, gentle reassurance, monitoring
