Chest wall rigidity can be caused by rapid infusion of which of the following opioid-
**Core Concept**
Chest wall rigidity is a well-documented side effect of certain opioids, particularly those with high lipid solubility and potency. This condition is characterized by the involuntary contraction of the intercostal muscles and diaphragm, leading to respiratory distress and difficulties in ventilation.
**Why the Correct Answer is Right**
Fentanyl, a synthetic opioid with high lipid solubility and potency, is known to cause chest wall rigidity. This phenomenon is thought to be mediated by the activation of opioid receptors in the central nervous system, specifically the mu-receptors, which are involved in regulating respiration and muscle tone. The rapid infusion of fentanyl can lead to a rapid increase in opioid concentrations, triggering this adverse effect.
**Why Each Wrong Option is Incorrect**
**Option A:** Morphine, although an opioid, is less likely to cause chest wall rigidity compared to fentanyl due to its lower lipid solubility and potency.
**Option B:** Pethidine (Meperidine) is more likely to cause muscle rigidity, but it is not the most potent or commonly implicated opioid in this context.
**Option C:** Buprenorphine, a partial opioid agonist, has a lower risk of causing chest wall rigidity compared to full agonists like fentanyl.
**Clinical Pearl / High-Yield Fact**
To minimize the risk of chest wall rigidity, it's essential to use opioids judiciously and titrate them carefully, especially in patients with pre-existing respiratory compromise or those at risk for opioid-induced respiratory depression.
**Correct Answer:** B. Pethidine (Meperidine)