Analgesics/NSAIDS - Magnesium Flashcards
What is the preoperative intravenous dose of Magnesium?
A) 25 mg/kg
B) 50 mg/kg
C) 75 mg/kg
D) 100 mg/kg
B) 50 mg/kg
Castillo MAGA:
50mg/kg IV preop, then …
8 mg/kg/hr intraoperatively
Significantly decreased fentanyl requirement
During an intraoperative drip, what is the recommended dosage of Magnesium?
A) 4 mg/kg/hr IV q4 hrs
B) 6 mg/kg/hr IV q2 hr
C) 8 mg/kg/hr IV q6 hrs
D) 10 mg/kg/hr IV q3 hrs
C) 8 mg/kg/hr IV q6 hrs
How does Magnesium enhance the effectiveness of opioids?
A) By increasing opioid receptor density in the brain
B) By blocking NMDA receptors, potentiating opioids centrally and peripherally
C) By directly stimulating opioid receptors
D) By increasing the bioavailability of opioids in the gastrointestinal tract
B) By blocking NMDA receptors, potentiating opioids centrally and peripherally
*Castillo MAGA:
-Anti-nociceptive effects
N-methyl-D-aspartate (NMDA) receptor antagonist
Probably potentiates opioids centrally and peripherally
Regulates
-Ca+ access into cell and actions within cell
-Neurotransmission
-Cell signaling
-Enzyme function*
Limited passage across BBB
C/I: Myasthenia gravis, renal failure.
What is the preop dose of Magnesium?
A) 50 mg/kg IV
B) 100 mg/kg IV
C) 150 mg/kg IV
D) 200 mg/kg IV
A) 50 mg/kg IV
Intraop drip dose: 8 mg/kg/hr IV Q6H (or 2g in first saline bag)
What is the intraoperative dose of Magnesium?
A) 8 mg/kg/hr IV Q6H (or 2g in first saline bag)
B) 10 mg/kg/hr IV Q6H (or 3g in first saline bag)
C) 12 mg/kg/hr IV Q6H (or 4g in first saline bag)
A) 8 mg/kg/hr IV Q6H (or 2g in first saline bag)
What is the primary mechanism of action of Magnesium?
A) Alpha-2 receptor agonist
B) NMDA receptor antagonist
C) COX-2 inhibitor
D) Opioid receptor agonist
B) NMDA receptor antagonist
Magnesium affects intracellular calcium levels by: (Select 2)
A) Blocking calcium channels to reduce calcium entry into cells
B) Increasing calcium ion release from intracellular stores
C) Regulating calcium within cells
D) Enhancing calcium uptake in the mitochondria
Answer: A) Blocking calcium channels to reduce calcium entry into cells
C) Regulating calcium within cells
regulation of Ca++ access into cell and within
How is Magnesium primarily eliminated from the body?
A) Hepatic metabolism
B) Renal excretion
C) Fecal elimination
D) Pulmonary excretion
B) Renal excretion
What is one of the primary actions of Magnesium in pain management?
A) Increasing opioid metabolism
B) Providing anti-nociceptive effects
C) Enhancing opioid absorption in the gastrointestinal tract
D) Stimulating pain receptors
B) Providing anti-nociceptive effects
Magnesium can significantly decrease the requirement for which of the following opioids?
A) Morphine
B) Hydromorphone
C) Fentanyl
D) Oxycodone
C) Fentanyl
In the event of a Magnesium overdose, what is a recommended treatment?
A) Administer additional Magnesium
B) Administer Calcium
C) Administer Naloxone
D) Administer Sodium bicarbonate
B) Administer Calcium
What precaution should be taken when administering Magnesium to patients with renal impairment?
A) Increase the dose to account for slower excretion
B) Use the standard dose without modification
C) Reduce the dose to accommodate for impaired renal clearance
D) Administer Magnesium only in the form of oral supplements
C) Reduce the dose to accommodate for impaired renal clearance
Which of the following is a common central nervous system (CNS) side effect of Magnesium?
A) CNS excitation
B) CNS depression
C) Increased alertness
D) Cognitive enhancement
B) CNS depression
What effect can Magnesium have on respiratory rate?
A) Increase respiratory rate
B) Decrease respiratory rate
C) Have no effect on respiratory rate
D) Cause irregular breathing patterns
B) Decrease respiratory rate
Which of the following side effects is associated with Magnesium and can be observed during a physical examination?
A) Increased deep tendon reflexes
B) Decreased deep tendon reflexes
C) Hyperactive reflexes
D) No change in reflexes
B) Decreased deep tendon reflexes
