Lecture 1 Flashcards
Unit 1
what are the three goals of pre-operative evaluation
- ensure patient will tolerate anesthesia
- mitigate perioperative risk
- clinical examination
What percentage of a diagnosis can be correctly determined from a patient history alone?
56%
What constitutes a medical history exam?
Underlying condition requiring surgery, medical history/problems, previous surgeries/anesthetic history, anesthetic complications, ROS, current meds, allergies, tobacco/ETOH/illicit drug use, functional capacity
What 4 things are BMI used to calculate (per powerpoint slide)?
1 - estimate/calculate drug dosages
2 - determine fluid volume requirement
3 - calculate acceptable blood loss
4 - adequacy of urine output
What is important to establish from a focused physical exam?
The patients baseline (neuro, CV, respiratory etc) in all systems
What acronym is used for an emergent physical exam? In an emergency if you can only pick 2, which do you pick?
A - allergies
M - medication
P - PMH
L - last meal
E - events leading up to surgery
Emergency pick 2 = allergies and PMH
What accounts for almost half of perioperative mortalities?
Cardiovascular complications
What is a G6PD deficiency?
The body lacks that enzyme, which causes hemolytic anemia. RBCs break down faster than they are made in response to stress
What court case established informed consent? Outcome of the surgery?
Salgo v Leland Stanford Jr. University Board of Trustees. An aortogram left the pt paralyzed
What surgeries carry a high mortality risk (>5%)? Intermediate (1 - 5 %) or low (<1%)?
High = aortic and major vascular surgery
Intermediate = Intra-abdominal or intrathoracic surgery, carotid endarterectomy, head/neck surgery
Low = ambulatory, breast, endoscopic, cataract, skin, urologic, orthopedic
What MET (metabolic equivalent of task) score is equivalent to good functional capacity?
greater than 4
Define emergency, urgent and time-sensitive surgeries
Emergent = life or limb would be threatened if surgery did not proceed within 6 hours
Urgent = life or limb would be threatened if surgery did not proceed within 6 - 24 hours
Time-sensitive = delays exceeding 1 - 6 weeks would adversely affect patient outcomes
What are Meyer Saklad’s components to risk stratification for his ASA PS grading of operative risk?
1 - Pt’s physical state
2 - the surgical procedure
3 - the ability/skill of the surgeon
4 - attention to post-op care
5 - past experience of the anesthetist in similar circumstances
What are the six degrees of ASA physical status according to Meyer Saklad chart?
I: normal healthy patient
II: patient with mild systemic disease
III: patient with severe systemic disease
IV: severe systemic disease that is a constant threat to life
V: patient not expected to survive without operation
VI: donor patient that is declared brain dead
Define: GA, IV/monitored sedation, Regional and Local anesthesia
GA = total LOC, ET or LMA, used in major surgeries
IV/Monitored = LOC ranges, drowsy to deep sleep. NC or face mask, requires vigilant observation
Regional = numbs a large part of the body using a local anesthetic (epidural or spinal), good for child birth or a hip replacement
Local = one-time injection that numbs a small area. Such as a biopsy
What agents most commonly have side effects in anesthesia?
Neuromuscular blockers, latex, antibiotics, chlorhexidine and opioids
What is the number one drug anesthesia gives that patients have a true allergic reaction to?
Rocuronium
What is the incidence of anaphylaxis involving anesthesia?
1 in 20,000
What medications do you continue prior to surgery?
HTN meds, BBs, anti-depressants, anxiolytics, TCAs (get an EKG), thyroid meds, oral contraceptives (unless they are at high risk of thrombosis, then dc 4 weeks prior), eye drops, Gerd, opioids, anti-convulsants, asthma, corticosteroids, statins, ASA (if high grade ischemic disease or prior PCI) COX2 inhibitors and MAOIs (avoid demerol and ephedrine)
What medications do you DC prior to surgery?
ASA, P2Y12 (plavix, prasugrel, ticlopidine), topical meds (dc day of) diuretics (except HCTZ), sildenafil, NSAIDs, Warfarin, post-menopausal HRT, non-insulin anti-diabetics (day of), short acting insulin (if insulin pump, keep it going), long acting insulin (type 1 = take 1/3 usual dose, type 2 = take none or up to half usual dose)
Echinacea effects?
Activates immune system, may decrease effectiveness of immunosuppressants and allergy concerns. No data about need to DC prior to surgery
Ephedra effects?
Increase HR/BP. Increase risk of stroke/tachycardia. Long term use can cause hemodynamic instability d/t decreased catecholamines. Stop 24 hours before
Garlic/Ginseng/Ginger/Ginkgo/Green tea effects?
Antiplatelet effects. Increased risk for bleeding. No data for ginger. Stop garlic/ginseng/green tea 7 days before, stop ginkgo 36 hours
Kava effects?
sedative, anxiolytic. Stop 24 hours before
Saw Palmetto
May increase bleeding risk, no data on when to stop
St Johns wort
Helps with depression. Linked with delayed emergence, stop 5 days before
Valeria
Sedation, may increase anesthetic requirements. No data on when to stop
What are the criteria in Mendelson syndrome that increase risk of aspiration?
greater than 25 ml in the stomach and a pH less than 2.5
What are the risk factors for PONV via the Apfel score? Koivuranta score?
Apfel = Female, hx of PONV, non-smoking status, post-op opioids,
Koi = Female, hx of PONV, non-smoking status, Age less than 50, and duration of surgery
Meds that can help prevent PONV?
Scopolamine (watch for dry mouth and takes a long time to work), Pregabalin (MOA unclear), Ondansetron (prevention, not treatment), Phenergan, Dexamethasone (works great with zofran), metoclopramide, PPI’s and H2 blockers
Most common antibiotics and dosages?
Ancef/ cefazolin (2 - 3 g, 30 mg/kg in peds, give q4h over 30 min)
Clindamycin (900 mg, 10 mg/kg in peds, give q6h over 30 - 60 min)
Vancomycin (15 mg/kg in adults/peds, infuse 15 mg/min
What should be conducted prior to administration of any mind-altering substance?
An anesthesia timeout, pt name, age, sex, hospital name, MRN, source of history and time of admission
Which patient populations are most at risk for latex allergies?
- healthcare workers
- patients with spina bifida
- food handlers
Which antibiotics are associated with the most allergies?
penicillin and cephalosporins
If we give a patient Vancomycin and the turn red is this an allergic reaction?
No. Red man syndrome can happen if the medication is given too quickly. Slow the rate down and it’ll be fine.
Allergies to local anesthetics is often the result of what?
reactions to esters are usually due to the preservative (PABA).
Which cross-reactivities are possible with NMBAs?
neostigmine and morphine (d/t ammonium ions)
What is the standard dose of hydrocortisone for patients on chronic steroids? Why do we give this?
100 mg q6. We give this to combat adrenal insufficiency (lack of cortisol produced over time d/t HPA suppression by the steroids)
