Anesthesia Flashcards
What is the definition of anesthesia?
is the process of blocking the perception of pain and other sensations. This allows patients to undergo surgery and other procedures without the distress and pain they would otherwise experience.
What is the definition of general anesthesia?
with reversible loss of consciousness
What is the definition of local anesthesia?
with reversible loss of sensation in a (small) part of the body by localized administration of anesthetic drugs at the affected site.
What is the definition of regional anesthesia?
with reversible loss of sensation and possibly movement in a region of the body by selective blockade of sections of the spinal cord or nerves supplying the region.
What are the goals of anesthesia?
Analgesia Sedation Reversible loss of consciousness Amnesia Muscle relaxation Hemodynamic stability Fast recovery
What happens if you do not have muscle relaxation?
will never get the fascia back together
What are the principles of anesthesia?
analgesia (local, regional, central) NSAIDS Local Anesthetics Acupuncture Opiates Hypnosis General Anesthesia
What is significant with opiods?
want to augment with another type to avoid dependency
What is minimal sedation?
anxiolysis
Normal response to verbal commands
Normal cardiovascular and respiratory status
What is moderate sedation?
(conscious sedation)
Purposeful response to verbal commands
Maintained airway, ventilation, cv-status
What is deep sedation?
Pt cannot be easily aroused
Purposeful response to repeat or painful stimulation
Airway and ventilation may be impaired
Cv-status maintained
What is sedation with general anesthesia?
Loss of consciousness
Airway and ventilation may need to be secured and maintained
Cv-status may be impaired
What happens at anxiolysis?
Patient can not consent to procedure at this point, patient is under baseline
What sedation is most oftenly used in the elderly and why?
conscious sedation; it reduces CV compromise
What are types of sedatives?
Benzodiazepines Barbiturates Ketamine Etomidate Propofol
What are the types of general anesthetics?
Gases
Sedatives
Why use analgesia with anesthesia?
Anesthesia w/ analgesia: Coming out of surgery is interesting (pt wakes up and looks at you, airway intact, pt goes home faster and needs less meds)
What do we use for amnesia?
Midazolam
Scopolamine
Anesthesia Gases
Why have amnestics became an important part of surgery?
dont want patient to remember surgery
What are the types of muscle relaxants?
Neuromuscular endplate
Nerve conduction
Nerve transmission
What are the types of neuromuscular endplates relaxants?
Nondepolarizing neuromuscular blocking agent
Depolarizing neuromuscular blocking agent
What are the types of nerve conduction relaxants?
Peripheral nerve blocks
Epidural anesthesia
What are the types of nerve transmission relaxants?
Spinal anesthesia
What is a specific case where we use non-depolarizing muscular blocking agents?
crush injuries
What is the goal of using muscle relaxants?
Goal is to get away from narcotics (since they have a lot of side effects: addiction, bowel problems)
What do we have to look at for hemodynamic stability?
Patient requirements Coronary and cerebral perfusion Preload Contractility Afterload Heart rate/rhythm Intentional hypo/hypertension: --Hypo- in cases of bleeding (to slow it down) --Hyper- cases of low perfusion; concern ischemia
What is a caution that we need to be aware of with a patient?
Preload; pts who are in house are NPO and you are giving them fluids so you have more CV stability
If pt has COPD or CHF you can give too much.. Delicate balance
Do you give a muscle relaxant to a pt with a B-blocker?
If pt is not on bblocker and you give right before surgery you can cause a stroke or MI
If pt is on bblocker you def give before surgery because it has been proven to improve outcomes (oral is better)
What is a specific medication you do not give before surgery?
ACE inhibitor
What is a type of local anesthesia?
lidocaine
What are the types of anesthesia?
local
general
regional
Why would you give epidural instead of lidocaine?
Epi causes it to stay longer so you can give more: ear tips, nose, lips do not give epi because low vascular areas
What are types of regional anesthetics?
Epidural Anesthesia
Spinal Anesthesia
Regional Block
Bier Block
When do you give a bier block?
when working on an extremity
What is a key factor you have to consider when using a spinal anesthetic?
Spinal is one shot one deal (good because if you give to pt it can go away by the time they wake up, but you can’t undo what you give.. Can give too much, have high spinal and cause resp depression)
What is a wet tap?
Wet tap means you’ve gone to far and drawn spinal fluid. You’ve gone through ligamentum flavum
What are epidural anesthetic effects?
Block of sensation of affected dermatomes Motor block of affected dermatomes Block of pain Block of sympathetic response Block of vagal response
What can the patient not do if you give them an epidural?
Pts w/ epi can not walk after
How can the patient present after getting an epidural?
Lots of pts w/ epis get hypotensive
What are relative contraindications to epidural anesthetics?
Patient unable to comprehend procedure
Prior back surgery or back pain
Fixed cardiac output states (AS)
What are absolute contraindications to epidural anesthetics?
Patient refusal Infection of skin Sepsis Patient anticoagulated Increased intracranial pressure
What is important to do before giving an epidural?
Sterilize the skin, Infection of skin can bring infx into spinal fluid
What are positives of epidurals?
Patient awake No depression of baby Postoperative analgesia Postoperative breathing Less risk of thrombosis Earlier intestinal motility No intubation
What are negatives to epidurals?
Failure of block Bleeding Infection Wet tap Bradycardia Hypotension Breathing difficulty
What do you do if you get a wet tap?
Can pull back, Put something in to stop bleed
Patient can get spinal h/a
What is a problem with a paravertebral epidural?
pneumothorax
What are the features of spinal anesthetics?
One shot Continuous spinal anesthesia Bilateral block Unilateral block Speed of onset Possibility of high spinal
When are spinal anesthetics most oftenly used?
More often used w/ obstretrics
What are contraindications for spinal anesthetics?
Same as for epidural anesthesia
Additional risk for heart failure patients due to increase in preload as block weans
Additional risk of sympathetic activation when block wears off
Risk if muscle relaxation is needed
What are the features of a regional block?
Peripheral nerve blocks Brachial plexus block --Interscalene --Infraclavicular Lumbar plexus block Continuous Nerve Sheath catheter
What are the choices of drugs for general anesthesia?
Total IV anesthesia
Balanced anesthetic
How do we do air way control for general anesthesia?
Oral and nasal airways
Mask anesthesia
LMA
Endotracheal intubation
What are air way issues?
The difficult airway
Gastroesophageal Reflux
Full stomach
Unstable neck
What about the spine can make the airway difficult?
if its fused
How do you control the air way in a trauma patient with an unstable neck?
have someone hold the c spine while you intubate
What is the number one cause of problems with the airway?
big tongue
What are possible problems the patient can present with that give them a difficult airyway?
Mallampati classification Mentomhyoid distance Mouth opening Neck mobility Buck Teeth Big tongue
What can someone have/get that increases the incidence of GERD/full stomach that would make it difficult to assess their airway?
History of GERD History of ESLD and Ascites Any Trauma Pregnancy Diabetes of long duration with supposed gastro paresis Rapid sequence induction Cricoid pressure Awake fiber optic intubation
What can give someone an unstable neck making it difficult to assess the air way?
Trauma Cervical Spine Fracture Atlanto-occipital Instability Spinal cord stenosis Awake fiberoptic intubation Awake positioning Inline stabilization
How do we secure the airway?
Mask ventilation Direct Laryngoscopy LMA/intubating LMA/combitube Fiberoptic Methods --Bronchoscope (flexible) --Bronchoscope (rigid) --Bullard Transtracheal Jet ventilation Tracheotomy
What is significant about the mask in securing the airway?
Mask: easiest to do but least security (less security that airway is maintained, and more risk of air going into stomach)
What are major clinical predictors?
Unstable coronary symptoms
Recent MI and risk of ischemia by clinical symptoms or noninvasive testing
Unstable angina
Severe valvular disease
Decompensated heart failure
Significant arrhythmias
High degree AV-block
Supraventricular arrhythmia with uncontrolled HR
Symptomatic ventricular arrhythmia with underlying heart disease
What are minor clinical predictors?
Advanced age Abnormal ECG (left ventricular hypertrophy, left bundle-branch block, ST-T abnormalities) Rhythm other than sinus Low functional capacity History of stroke Uncontrolled systemic hypertension
What are intermediate clinical predictors?
Mild angina pectoris
Previous MI by history or pathological Q waves Compensated or prior heart failure
Diabetes mellitus
Renal insufficiency
What would require further preop testing?
2 out of 3 positive:
Intermediate clinical predictors Low functional capacity High surgical risk --Aortic surgery --Peripheral vascular procedures --Long procedures with fluid shifts and blood loss
If the patient can do _____________, they are probably ok for surgery.
walk up 2 flights of stairs
What are examples of non-invasive testing?
Stress test Thallium stress Dobutamine stress echocardiography Dipyridamole or adenosine perfusion Holter recording
If the non invasive testing is positive what is next?
coronary angiography
