Perioperative Care Flashcards
What is the goal of antibiotic prophylaxis for a surgery
Adequate antibiotic serum and tissue levels for the time during which surgical site is open
What are the three key measures for antibiotic prophylaxis
1) Antibiotic is appropriate for type of surgery
2) Antibiotic is given within one hour prior to surgical incision to optimize adequate tissue levels at time of surgical incision
3) Antibiotic is discontinued within 24 hours after surgery
Which antibiotics should be given two hours before surgical incision
Vancomycin, metronidazole, levofloxacin, and ciprofloxacin
Which surgery is antibiotics discontinued greater than 24 hours later, how much later
Cardiac surgery, 48 hours
What are the types of surgical wounds, top two
Clean, clean-contaminated, contaminated, dirty-infected/ clean and clean-contaminated
What is a viscus
An internal organ of the body, specifically one in the chest (heart or lungs) or abodmen (liver, pancreas, or intestines)
What is the difference between a clean surgical wound and clean-contaminated surgical wound
Clean: a viscus is not entered and no inflammation is encountered
Clean-contaminiated: a viscus is entered and no unusual contamination
T/F: A goal for the choice of antibiotics for surgery is the most narrow spectrum of activity that targets the most common organisms for anatomic region being operated on
True
What is the antibiotic of choice for most surgical procedures
Cefazolin
What are alternatives when cefazolin alone is appropriate
Clindaymcin (less efficacious, may add gentamicin) and vancomycin (select patients, high risk or currently MRSA positive)
When is cefazolin alone not sufficient, what is added
When a viscus is entered (clean contaminated), cefazolin and metronidazole OR cefatoxin
Howl long the antibiotic be in the system
During the entire the surgical site is open
What is the cefazolin dose for preoperative use, when and how should redosing occur
2 grams IV for patients greater than 80 kg OR 3 grams IV for patients greater than 120 kg/ redose after 4 hours (two half-lives) or excessive blood loss (greater than 1500 ml)
T/F: Most patients who have a penicillin allergy have a hypersensitivity reaction
False: Up 10% of hospitalized patients report a PCN allergy but as many as 80-90% of those DO NOT have a Type 1 IgE-mediated hypersensitivity reaction (80% of those with penicillin allergy lose it over time)
T/F: Patients with low or moderate risk of a PCN hypersensitivity reaction will still receive cefazolin
True
What drugs are given for induction/intubation
Propofol (produce unconsciousness) and Neuromuscluar blocking agent/NMBA ( facilitate intubation)
What drugs are given for maintenance
Inhaled anesthetic agent and NMBA (maintain paralysis)
What drugs are stopped and reversed
Inhaled anesthetic agent is turned off and NMBA is reversed
What is given and how is it to induce rapid onset of unconsciousness
Propofol. single bolus induction dose
`What are the kinetics of propofol
Rapid onset due to high lipid solubility with a short duration of action due to rapid redistribution into muscle then fat
What are the doses for sedation, induction of general anesthesia, and maintenace of general anesthesia
Sedation: 25-75 mcg/kg/min continuous infusion
Induction of general anesthesia (unconsciousness): 1-2.5 mg/kg IV bolus dose
Maintenance of general anesthesia: 50-200 mcg/kg/min continuous infusion
T/F: The dose for propofol should be adjusted with severe hepatic and renal disease
False: Presence of hepatic or renal disease causes no significant effect
What are the adverse effects of propofol
Hypotension, respiratory depression, and pain on injection
What are the 3 clinical uses for NMBAs
Facilitate intubation, maintain paralysis during surgery, paralysis in the ICU for mechanically ventilated patients
T/F: NMBAs only produce muscle paralysis and THEY DO NOT produce sedation or analgesia
True
How does nueromuscular transmission usually work
Acetycholine is released, activates nicotinic receptors on motor end plate, channel opens leading to depolarization with an action potential generated along entire muscle fiber for a muscle contraction
What removes acetylcholine and allows for repolarization
Diffusion and acetylcholine destruction by acetylchlolinesterase/AChE)
What are the non-depolarizing NMBAs
Rocuronium, cisatracurium Vecuronium, Atracurium
What is the difference in MOA between depolarizing and non-depolarizing NMBAs
Succinycholine (depolarizing) binds to nicotinic receptors at motor end plate generating an action potential and is slower to dfffuse away for prolonged depolorization WHILE nondepolarizing bind to nicotinic receptors and PHYSICALLY BLOCK Ach from binding causing NO ACTION POTENTIAL AND NO DEPOLARIZATION
When is succinlycholine indication, why
Endotracheal inutation, fastest onset and shortest duration
What are the severe adverse effects of succinlycholine
anaphylaxis bradycardia (children), hyperkalemia, trigger malignant hyperthermia
Which NMBA is the most commonly used, why, 2nd line
Rocuronium (fastest onset: 60-90 sec)/ cisatracurium (doesn’t need hepatic or renal elimination while rocuronium does)
What two drugs are most used to reverse paralysis caused by NMBA, how does each work
Neostigme: inhibits AChE allowing for Ach to displace residual NMBAa from noicotinic receptors/ Sugammadex: gamma cyclodextrin that binds rocuronium rendering rocuronium inactive
What are the adverse effects of neostigmine, what is the caveat of using this drug
Bradycardia, hypotension, N/V, salivation/ always combined with anticholinergic since neostigmine is not specific to just nicotonic receptors)
What anticholinergics ARE ALWAYS GIVEN with neostigmine
Glycopyrrolate and atropine (block cholinergic effects at muscarinic receptors)
What are the inhaled anesthetic agents
Isoflurance, Desflurane, sevoflurane
What is the order of inhaled anesthetic agents for onset
desflurane (fast onset and fast offset), sevoflurane, and isoflurane
Which inhaled anesthetic agent should be used for induction of general anesthesia, which should not
Sevoflurane, desflurane
