Perioperative Drugs Flashcards
When you you give oral drugs pre-operatively?
60-90 minutes pre-op
When do you give IM drugs pre-operatively
30-60 minutes pre-op
What drug do you give the night before surgery?
Benzodiazepine PO
What drugs do you give 1-2 hours before surgery?
Benzodiazepine PO 150 mL water Opioid IM Scopolamine Cimetidine and/or metoclopramide Glyropyrrolate or Atropine IM
What is the opioid IM pre-op for?
analgesia
What is the scololamine pre-op for?
amnesia and sedation
What is the role of benzodiazepines in pre-op care?
Amnesic, calming sedative effect with NO analgesia.
What are the benzodiazepines with the longest half-lives?
Diazepam
Lorazepam
Which benzodiazepines can be give IM?
Lorazepam
Temazepam
What is promethazine used for in pre-op care?
Decrease anxiety
Lower threshold for seizures
What are 1st generation antihistamines used for in pre-op care?
Bronchodilator Sedative Anxiolytic Analgesic Anti-emetic Cholinergic antagonism (dries secretions)
Which 1st generation antihistamines are used in pre-op care?
Hydroxyzine
Diphenhydramine
How do H1 and H2 antagonists differ?
drugs like cimetidine and ranitidine DO NOT have sedative, cholinergic antagonism, or an ant-emetic effect like H1 antagonists
When do you use opiates in the peri-operative period?
Opiates used to be given before surgery, but now they are only given if the patient is in pain.
Whcih Opioids can be give IM?
morphine
codeine
What are some toxicities associated with opiates?
- Orthostatic hypotension, epigastic distress, antidiarrheal, increased sphincter tone
- N/V via chemoreceptor trigger (DA antagonism) + delay of GI transit + increased GI secretions
- Respiratory depressant + coma inducing + miosis inducing
When are NSAIDs used in the peri-operative period?
Post-op pain management (try to transfer from opioid to this as quickly as possible)
Which NSAIDs are used in the peri-operative period?
Ketorolac
Ibuprofen
What are some toxicities of NSAIDs?
- Post surgical bleeding outside GI tract (reduced platelet aggregation, but most surgery (excluding GU, cardiac and oral) are not significantly impacted by NSAID-reduced hemostasis
- Fracture healing is impaired with COX-2 inhibitors (possibly)
Why do you do gastric preparation prior to surgery?
Neutralization of stomach acid is important in reducing the likelihood of aspiration of gastric contents into the pulmonary system during surgery. Such aspiration can severely damage lung tissue, indeed severe cases can be fatal.
What drug classes are used in GI preps?
H2 receptor antagonists
NP Antacids
D2 receptor antagonist
MOA: Gastrokinetic agent that accelerates gastric emptying.
Metoclopramide (D2 receptor antagonist)
What is another beneficial effect of metoclopramide in the pre-operative period?
Also provides sedation and lowers seizure threshold (via DA antagonism)
MOA: -Rapid reduction of rate of acid secretion with few CNS effects
Cimetidine
Rantidine
(H2 receptor antagonists)
True or false: H2 receptor antagonists stimulate gastric emptying/alter existing stomach volume
FALSE!
MOA: Neutralize existing GI contents with no lag time
Non-particulate Antacids (Bicitra, Polcitra)
TOXICITY: HA, confusion, seizures, agitation in the elderly
Cimetidine
Rantidine
DDI: antagonized by anticholinergics and narcotics
metoclopramide
What are the three major drugs used to combat N/V after same-day surgery?
Ondansetron
Scopolamine
Metoclopramide
What is ondansetron?
Serotonin 3 antagonist
Where do anti-emetic drugs work?
CTZ or signals arising from GI tract
What is an IV anesthetic with antiemetic qualities that is used for post-op N/V (especially if sedation involved N2O)?
Propofol
What drugs are given to patients at increased risk of allergic reaction to block consequences of histamine release (not prevent it from occurring)?
H1 and H2 receptor blockers (ex. aminophylline, hydrocortisone, methylprednisone, epinephrine)
Antibiotic prophylaxis against most staph and strep
Cefazolin
Antibiotic prophylaxis against bowel anaerobes
Cefotetan
Cefoxitin
Antibiotic prophylaxis against MRSA
DON’T DO THIS! (but can use vancomycin)
Why are anticholinergics used in the peri-operative period?
Vagolytic effect (mitigate reflex bradycardia)
Antisialogogue (block muscarinic stimulation arising from use of anti-cholinesterase drugs)
Sedation/Amnesia
List the anticholinergics used in the perioperative period.
Atropine
Scopolamine
Glycopyrrolate
Which anticholinergic has sedation/amnesia action?
scopolamine
Which anticholinergic has the strongest anti-sialogogue action?
Glycopyrrolate
Which anticholinergic has the strongest vagolytic effect (increase heart rate)?
atropine
What do you do before intubation?
- Give oxygen
- Give IV prophylactic drugs
- Possibly give succinylcholine (block NMJ)
Who gets lidocaine as prophylaxis for intubation?
increased ICP
Penetrating injury
reactive airway disease
What does lidocaine do to help with intubation?
decreased intracranial and bronchospastic response
Who gets fentanyl as prophylaxis for intubation?
increased ICP
hemorrhage
CV disease
What does fentanyl do to help with intubaiton?
decrease sympathetic response to laryngoscopy/intubation
Who gets atropine as prophylaxis for intubation? Why?
children under 10 (to mitigate the bradycardia in response to succinylcholine)
Who gets vecuronium as prophylaxis for intubation?
Increased ICP
Penetrating injury
What does veruronium do to help with intubation?
defasciculates and mitigates ICP resposne to succinylcholine
What is a potential problem with administering a narcotic antagonist to reverse respiratory depression?
high doses can allow pain to return and increase HR and GP
How do you treat post-op hypotension?
fluids, dopamine (beta effect + renal preservation), or phenylephrine or epinephrine with spinal or epidural hypotension
How do you treat post-op hypertension?
usually due to pain or fluid overload and resolves on its own in <4 hours; can give rapid acting vasodilators like nitroprusside or (rarely) ganglionic blockers like trimethaphan.
What is the most common reason for delayed awakening?
residual anesthetics and ancillary drugs
usually narcotics or benzodiazepines
When can you count out an NMB as the cause of delayed awakening?
if the patient has no respiratory depression
What drug can be used to reverse anti-Ach effects of some sedatives and inhalational agents?
physostigmine
True or false: there is little correlation between cognitive decline and the type of anesthesia and cardiovascular stability in the post operative and the development of cognitive decline.
True
What is the initial management of anaphylaxis in surgery?
The initial response to an anaphylactic reaction is to stop the administration of the precipitating factor and to terminate anesthesia as rapidly as possible.
Waht do you do after you stop the anaphlyaxis-causing agent?
Give O2. Patients may require epinephrine and vascular volume expansion to provide for cardiovascular support.
What drug can be given to treat persistent bronchospasm after anaphylaxis?
aminophylline
What drug can be given to treat acidosis after anaphylaxis?
Sodium Bicarbonate
What are the three classes of drugs used in secondary management of anaphylaxis?
Antihistamines
Catecholamines
Corticosteroids
