Chronic Pain and Psych, Substance Abuse, Drug OD

Question 1

A patient with a history of opioid tolerance is considered for ketamine infusion as part of perioperative pain management for spinal fusion surgery. Given ketamine’s mechanism of action, which of the following best explains its efficacy in this patient’s pain management strategy?

Answer 1

Ketamine antagonism of NMDA receptors reduces central sensitization, thereby mitigating the development of chronic post-surgical pain and opioid induced hyperalgesia.

Question 2

In the context of systemic lidocaine infusion for acute perioperative pain management, which of the following best describes the underlying pathophysiological mechanism for its prolonged analgesic and anti-inflammatory effects?

Answer 2

Lidocaine modulates inflammatory response and inhibits pain pathways by acting on NMDA receptors, PMNs, and blocking sodium channels which extends its analgesic effect beyond its plasma half life.
Rationale:

Question 3

A patient with chronic opioid therapy presents with generalized, burning pain that is more intense than their baseline chronic pain. This new onset of pain is not associated with any new pathology. Considering the mechanisms behind opioid-induced hyperalgesia (OIH), which of the following best explains the pathophysiological basis for the patient’s symptoms?

Answer 3

OIH is characterized by increased production of nociceptive neurotransmitters such as substance P and OGRP, and the sensitization of peripheral nerve endings leading to enhanced pain perception.

Question 4

A patient on buprenorphine therapy for chronic pain management is undergoing elective surgery. Given buprenorphine’s pharmacological profile, what is a key consideration in managing acute postoperative pain in this patient?

Answer 4

Given buprenorphine high receptor affinity it can replace opioid agonist from receptor. The long half life (6 hours) and the reported analgesic ceiling effect provide further potential for uncontrolled post-op pain. Consider the use of multimodal analgesics and regional anesthesia when appropriate.

Question 5

Which of the following best describes the pathophysiological mechanisms contributing to phantom limb pain (PLP) in patients following limb amputation?

Answer 5

PLP arises from a combination of peripheral nerve changes, including neuroma formation, and central changes such as central sensitization and cortical reorganization

Question 6

In the context of Phantom Limb Pain (PLP), which of the following statements most accurately describes the interaction between peripheral and central mechanisms contributing to the sensation of pain in the absent limb?

Answer 6

The development of neuromas at the site of nerve severance leads to aberrant ectopic discharges, which, in conjunction with cortical somatosensory reorganization, results in the brain interpreting these signals as originating from the absent limb.

Question 6

Which nonpharmacologic intervention has been reported as effective for phantom limb pain (PLP) in both lower and upper limb amputees?

Answer 6

Mirror Therapy

Question 7

Considering the impact of renal or hepatic disease in cancer patients on the metabolism and effects of analgesic medications, particularly acetaminophen and NSAIDs, which pathophysiological considerations are critical for nurse anesthesiologist in planning postoperative pain management?

Answer 7

Any disease burden that involves the liver or hepatic blood supply may result in alterations in coagulation; therefore, appropriate lab work, including platelets, INR, prothrombin (PT)/ partial thromboplastin time (PTT), must be drawn prior to regional or neuraxial procedures.

Question 7

In cancer patients with chronic pain who are undergoing surgery, the phenomenon of opioid tolerance and opioid-induced hyperalgesia (OIH) presents a significant challenge for postoperative pain management. Considering the pathophysiological mechanisms involved, which statement best explains why these patients may require higher doses of intraoperative opioids and the inclusion of adjuncts like methadone or ketamine?

Answer 7

The etiology of pain may be from disease progression, iatrogenic, or unrelated to their cancer (e.g., myofascial pain from deconditioning, diabetic neuropathy, or osteoarthritis). Often these patients are on preoperative opioid analgesics, which can result in tolerance and/or hyperalgesia. Therefore, may require higher doses on intraoperative opioids, an escalation of the opioid dose in the immediate postoperative period, as well as adjuncts such as intraoperative methadone or ketamine. It is critical to review the possible systemic effects of the malignancy and treatment and how it may impact pain management.

Question 8

In managing fibromyalgia patients perioperatively, the use of gabapentinoids is recommended to address central sensitization. What pathophysiological mechanism underlies the effectiveness of gabapentin and pregabalin in this patient population, particularly in the context of perioperative pain management?

Answer 8

Gabapentinoids modulate calcium channel function at the spinal and cortical levels, reducing aberrant neuronal firing and thereby mitigating central sensitization seen in fibromyalgia.

Question 9

How do systemic effects of malignancy, such as cerebral metastatic disease burden and electrolyte abnormalities, complicate the management of pain in cancer patients from a pathophysiological perspective?

Answer 9

Cerebral metastatic disease burden, as well as electrolyte abnormalities and malnutrition, may affect the patient’s mental status and sometimes require adjustments in analgesic agents.

Question 10

Considering the pathophysiology of CRPS and its implications for perioperative pain management, why might ketamine infusions at subanesthetic doses be particularly beneficial for patients with CRPS undergoing surgery?

Answer 10

Ketamine’s NMDA receptor antagonism plays a critical role in interrupting the central sensitization process that characterizes CRPS, potentially reducing the perpetuation of pain signals.

Question 11

In patients with severe obesity undergoing surgery, why is the optimization of multimodal analgesia, including the use of systemic lidocaine and α2 agonists, particularly important in minimizing postoperative pain and enhancing recovery?

Answer 11

These meds allow for an opioid sparing pain regimen; severely obese patients have concurrent OSA, this reduces the potential for airway-related and respiratory complications.

Question 12

During surgery, the use of electrosurgical instruments can pose a risk to patients with SCS devices due to electromagnetic interference (EMI). Considering the pathophysiological implications of EMI on SCS function, which of the following recommendations is most appropriate to minimize the risk of inadvertent reprogramming or device malfunction?

Answer 12

It is recommended that prior to all procedures the device be reprogrammed to the lowest amplitude and turned off prior to induction, which decreases inadvertent reprogramming during surgery from EMI

Question 12

A 47-year-old patient with a history of chronic neuropathic pain, managed with spinal cord stimulation (SCS), is scheduled for elective laparoscopic cholecystectomy. The patient reports significant relief of pain symptoms with the SCS device but expresses concern about the potential for postoperative pain exacerbation and the impact of surgery on the functionality of their SCS device. The surgical team plans to use electrosurgical instruments during the procedure, raising concerns about electromagnetic interference (EMI) and the risk of SCS device malfunction or inadvertent reprogramming. Given the patient’s dependence on the SCS device for pain management and the necessity of using electrosurgical instruments during laparoscopic surgery, understanding the pathophysiological and technological aspects of managing SCS devices in the surgical environment is crucial for optimal perioperative care.
Clinical Scenario Question:
Considering the potential for EMI from electrosurgical instruments to affect the SCS device during laparoscopic cholecystectomy, which perioperative management strategy best mitigates the risk of device malfunction while ensuring effective postoperative pain control?

Answer 12

It is recommended that prior to all procedures the device be reprogrammed to the lowest amplitude and turned off prior to induction, which decreases inadvertent re- programming during surgery from EMI p.615
Integration with SCS therapy: coordinating postoperative analgesia with the existing SCS settings and manufacturer. Post-operative assessment of the SCS device’s functionality and programming.

Question 13

Considering the potential risks associated with conducting MRI procedures on patients with implanted SCS devices, such as magnetic pull, device damage, unwanted stimulation, and thermal injury, which statement best describes the appropriate pre-procedural steps to mitigate these risks?

Answer 13

It is recommended that prior to an MRI the device manufacturer and model are identified, and the device representative can provide information about under what MRI conditions the device can be scanned. If elective, delay until adequate information can be obtained.

Question 14

A pregnant patient with a history of Complex Regional Pain Syndrome (CRPS) managed with spinal cord stimulation (SCS) presents for a scheduled cesarean section. The patient has been experiencing increased CRPS symptoms during pregnancy, including heightened pain and altered sensation in the affected limb, alongside typical physiological changes of pregnancy such as increased cardiac output and blood volume, as well as hormonal fluctuations. These changes have necessitated adjustments to her SCS device settings to manage the exacerbated CRPS symptoms effectively.

Given the intricate pathophysiological interactions between CRPS, the physiological adaptations of pregnancy, and the neuromodulatory effects of SCS, which of the following considerations is paramount in planning anesthesia for the cesarean section to ensure optimal pain management and maternal-fetal safety?

Answer 14

Utilize a multimodal anesthesia approach that includes careful adjustment of the SCS settings, tailored neuraxial anesthesia to manage CRPS and surgical pain, and close monitoring of maternal and fetal well-being, considering the pathophysiological implications of CRPS exacerbation and pregnancy on anesthetic choices and fetal health.

Question 15

Given the lack of definitive studies on the effect of spinal cord stimulation (SCS) on human fetal development and the theoretical concerns about teratogenic and abortifacient effects, what is the most prudent approach to managing pregnant patients with implanted SCS devices?

Answer 15

Although there are no studies examining the effect of SCS on human fetal development, the current recommendation of SCS manufacturers is to inactivate the device at gestation.

Question 16

In patients with treatment-resistant major depression undergoing electroconvulsive therapy (ECT), a procedure known to be effective when antidepressant drugs or psychotherapy have failed, what specific anesthetic considerations must be taken into account given the pathophysiological underpinnings of the treatment?

Answer 16

The patient is preoxygenation before induction. Anticholinergics may be administered as an antisialagogue or to prevent asystole. The induction agent is administered intravenously. Methohexital, propofol, or etomidate may be used without compromise of the therapy. Ketamine is used, although an enhanced hemodynamic response and increased intracranial pressure are possible after using ketamine. After loss of consciousness, positive pressure ventilation is applied to the patient via the breathing bag and a facemask and is continued until after treatment is completed and spontaneous respirations resume. Succinylcholine is typically the muscle relaxant of choice for ECT because of its rapid onset, short duration, and independent reversibility.

Question 17

Given the neurochemical hypothesis that depression is associated with decreased availability of norepinephrine and serotonin at specific synapses in the brain, how might the use of certain anesthetic agents that influence these neurotransmitter systems impact the perioperative management of patients with major depression?

Answer 17

Patients with major depression may exhibit altered responses to anesthetic agents that affect serotonin and norepinephrine reuptake, such as increased sensitivity to drugs with serotonergic or noradrenergic activity, necessitating careful selection and dosing of anesthetic agents to avoid exacerbating depressive symptoms or precipitating serotonin syndrome.

Question 18

Given the established link between chronic depression and alterations in amine neurotransmitter pathways, particularly serotonin and norepinephrine, a patient with a diagnosis of major depression undergoing elective surgery presents a unique challenge in anesthetic management. The patient has been on a regimen of selective serotonin reuptake inhibitors (SSRIs) and is scheduled for a procedure known to induce significant postoperative pain. Considering the pathophysiological impact of SSRIs on serotonin pathways and the potential for perioperative pain to exacerbate depressive symptoms, which strategy would optimize the patient’s anesthetic care while mitigating the risk of postoperative depression exacerbation and managing pain effectively?

Answer 18

Incorporating perioperative plan than includes the continuation of SSRIs, utilization of low dose ketamine as an adjunct for its antidepressant effects and to provide analgesia through NMDA receptor antagonism, and careful monitoring for signs of serotonin syndrome, aims to balance the management of depression, postoperaitve pain, and anesthesia safely.

Question 19

Given the primary mechanism of action of SSRIs in inhibiting serotonin reuptake at the presynaptic neuron, enhancing serotonergic activity in the synaptic cleft, how does this modulation of serotonin levels influence the pathophysiological basis of SSRIs’ therapeutic effects in disorders beyond major depression, such as irritable bowel syndrome (IBS) and panic disorders?

Answer 19

The enhancement of serotonergic activity by SSRIs modulates central and peripheral neural pathways involved in the regulation of mood, anxiety, and gastrointestinal function. In conditions like IBS, increased serotonin levels in the gastrointestinal tract can improve motility and pain signaling, while in panic disorders, enhance serotonergic neurotransmission in the brain can regulate anxiety circuits and mitigate panic symptoms

Question 20

Considering the phenomenon of SSRI discontinuation syndrome, particularly with drugs like paroxetine and fluvoxamine that have short half-lives and no active metabolites, what pathophysiological mechanisms underlie the emergence of symptoms upon abrupt cessation of therapy, and how do these mechanisms inform strategies for managing discontinuation?

Answer 20

Abrupt discontinuation of SRI medications can lead to withdrawal symptoms, and the SRI discontinuation syndrome has received increasing attention as a clinical concern influencing management. A gradual and “hyperbolic” tapering course is recommended, with initial decrements followed by increasingly smaller steps as the taper progresses.

Question 21

A 38-year-old patient with a history of chronic migraine managed with a combination of SSRIs and triptans is scheduled for elective laparoscopic cholecystectomy. Given the patient’s history, there is a heightened concern for the potential reoccurrence of serotonin syndrome, previously experienced two years ago during an episode of acute migraine management. The anesthesiology team is tasked with devising a perioperative analgesic plan that minimizes the risk of serotonin syndrome while effectively managing surgical pain.
Considering the pharmacodynamic interactions that precipitated serotonin syndrome in this patient, how should the anesthesiology team formulate a perioperative analgesic strategy to mitigate the risk of serotonin syndrome recurrence while ensuring adequate pain control?

Answer 21

The team decides on a multimodal analgesia approach that avoids additional serotonergic drugs, incorporating non-steroidal anti-inflammatory drugs (NSAIDS), acetaminophen, and a low dose ketamine infusion, given its NMDA receptor antagonist properties and minimal effect on serotonin levels. This strategy is complemented by regional anesthesia to provide targeted pain relief without exacerbating serotonergic activity.

Question 22

A 70-year-old male with a history of hypertension and depression, treated with an SSRI and a beta-blocker, undergoes a total hip replacement. Postoperatively, he develops high fever, muscle rigidity, and altered mental status. No neuroleptic medications were used preoperatively or intraoperatively.
Question: Based on his symptoms, medication history, and absence of neuroleptic use, what is the most likely diagnosis for this patient’s postoperative condition, and what are the immediate treatment steps?

Answer 22

While Neuroleptic Malignant Syndrome also presents with fever, muscle rigidity, and altered mental status, it is typically associated with the use of dopamine antagonist medications (neuroleptics) such as antipsychotics, which the patient was not given preoperatively or intraoperatively. This, combined with the patient’s SSRI use, makes serotonin syndrome the more likely diagnosis.

Question 23

A 55-year-old patient develops acute onset agitation, confusion, tachycardia, and hypertension two days after starting a postoperative course of a serotonergic analgesic for chronic pain management following a total knee replacement.
Question: Considering the time to onset and the causative drugs listed, which hyperthermic syndrome aligns with the patient’s symptoms, and what clinical feature could help distinguish this condition from others with similar presentations?

Answer 23

Serotonin syndrome is the most consistent with the patient’s presentation, considering the recent introduction of a serotonergic analgesic. The presence of hyperreflexia and clonus would help distinguish serotonin syndrome from other hyperthermic syndromes that do not commonly present with these neuromuscular findings.

Question 24

A patient on irreversible nonselective MAOIs is undergoing elective abdominal surgery. Intraoperatively, the patient develops significant hypotension. Considering the pharmacological action of MAOIs and their effects on neurotransmitter levels, which of the following management strategies is most appropriate for addressing this hypotension?

Answer 24

Phenylephrine administration with careful dose adjustment

Question 25

For a patient undergoing outpatient dental surgery who is being treated with selegiline (a selective MAO-B inhibitor) for Parkinson’s disease, which induction agent is most appropriate to minimize the risk of adverse effects related to the patient’s MAOI therapy?

Answer 25

The choice of nondepolarizing muscle relaxants is not influenced by treatment with MAOIs. Avoid ketamine, as it is a CNS stimulant (pg.623). Avoid serotonergic drugs (pg. 622, table 29.3)

Question 26

A 68-year-old patient with a history of ischemic heart disease and a recent myocardial infarction is scheduled for electroconvulsive therapy (ECT) due to severe, treatment-resistant depression. Given the cardiovascular risks associated with ECT, which of the following pre-treatment strategies is most appropriate to mitigate the risk of myocardial ischemia and dysrhythmias during the procedure?

Answer 26

Labetalol, esmolol, CCB all attenuate hemodynamic responses to ECT. Dexemedetomidine has been shown to be effective in controlling BP without affecting seizure duration

Question 27

A patient with a history of well-controlled hypertension is undergoing ECT for severe bipolar disorder. Considering the cerebrovascular effects of ECT, which of the following is the most appropriate measure to minimize the risk of a hypertensive crisis and subsequent increase in intracranial pressure (ICP) during the procedure?

Answer 27

The magnitude of treatment-induced hypertension can be ameliorated with use of nitroglycerin intravenously, sublingually, or transdermally. Likewise, esmolol 1 mg/kg IV administered just before induction of anesthesia can attenuate the tachycardia and hypertension associated with ECT, and it does so better than labetalol. Many other drugs, including calcium channel blockers, ganglionic blockers, ±2-agonists and antagonists, and direct-acting vasodilators, have been used to treat the sympathetic overactivity during ECT, but they do not appear to offer any specific advantages over esmolol or nitroglycerin therapy

Question 28

A 29-year-old male with schizophrenia, treated with high-potency antipsychotics, is admitted to the ICU with hyperpyrexia, severe muscle rigidity, and altered consciousness. He has a history of similar episodes shortly after antipsychotic dose adjustments. Given the clinical presentation and history, the primary diagnosis is Neuroleptic Malignant Syndrome (NMS). Which of the following is the most appropriate initial treatment approach?

Answer 28

Immediate cessation of antipsychotic medication and initiation of supportive therapy including mechanical ventilation, hydration, and cooling

Question 29

A 45-year-old patient with a history of severe alcohol use disorder is scheduled for elective surgery. The patient has been abstinent for 48 hours and exhibits mild tremors and hypertension. Which of the following is the most appropriate initial management strategy?

Answer 29

Typically, symptom-based treatment of alcohol withdrawal syndrome with benzodiazepines is the standard treatment for uncomplicated alcohol withdrawal syndrome. Diazepam or lorazepam are generally the preferred agents to use. Adjuvant medications such as clonidine, hydroxyzine, and trazodone as needed can help with the associated anxiety and insomnia that accompany alcohol withdrawal syndrome.

Question 30

A patient with a history of chronic alcohol use is admitted for surgery and has been receiving high-dose intravenous thiamine to prevent Wernicke-Korsakoff syndrome. What is the primary pathophysiological rationale for administering high-dose thiamine in this patient?

Answer 30

Thiamine is crucial for carbohydrate metabolism, and its deficiency can lead to neuronal damage, particularly in regions involved in memory and coordination.

Question 31

A patient on long-term naltrexone therapy for alcohol use disorder is scheduled for elective surgery. What is the most appropriate strategy for managing analgesia in this patient?

Answer 31

Naltrexone is an opioid antagonist
Patients who are prescribed oral naltrexone should anticipate needing to discontinue oral naltrexone 72 hours prior to surgery. Long-term opioid antagonism can increase the opioid receptor density in the brain, which may cause patients treated with naltrexone to be more sensitive to opioid agonists. Consider non-opioids when possible
If patients are receiving naltrexone at the time of their surgery, higher affinity full opioid agonists such as fentanyl or hydromorphone with close monitoring will likely need to be utilized.

Question 32

In a patient with severe alcohol use disorder undergoing surgery, which of the following is a critical consideration for electrolyte management?

Answer 32

Aggressive correction of hypomagnesemia and hypophosphatemia to prevent complications such as cardiac dysrhythmias and muscle weakness.

Question 33

A patient with a recent history of cocaine use is undergoing emergency surgery. Which of the following management strategies is most appropriate to mitigate the risk of cocaine-induced myocardial ischemia?

Answer 33

Labetalol; Any event or drug likely to increase already enhanced sympathetic activity must be avoided. It seems prudent to have nitroglycerin readily available to treat signs of myocardial ischemia associated with tachycardia or hypertension.

Question 34

A patient with a history of cocaine use is evaluated for elective surgery. What is the most critical consideration for anesthesia management in this patient?

Answer 34

Potential for labile bp’s and tachyarrhythmias. Intraoperative monitoring should include vigilant CV assessment. Increased risk for seizures, risk of hemorrhagic or ischemic strokes, alters cerebral blood flow, pulmonary

Question 34

In the management of acute cocaine intoxication presenting with hyperthermia, which of the following interventions is most appropriate?

Answer 34

Administration of IV benzodiazepines is effective in controlling seizures associated with cocaine toxicity. Active cooling may be necessary if hyperthermia is significant.

Question 35

A 32-year-old patient with a history of opioid use disorder OUD is undergoing elective surgery. They are currently on buprenorphine-naloxone maintenance therapy. Which of the following is the most appropriate management strategy for this patient’s perioperative pain?

Answer 35

Continue buprenorphine-naloxone therapy and utilize full opioid agonists as needed for breakthrough pain, along with multimodal analgesia.

Question 36

A patient experiencing opioid withdrawal in the perioperative setting is showing signs of severe discomfort, including diaphoresis, hypertension, and tachycardia. Which of the following medications is most appropriate for treating opioid withdrawal symptoms in this context?

Answer 36

Methadone or full opioid agonist; buprenorphine-naloxone; clonidine

Question 37

When managing anesthesia in a patient with chronic opioid use, which of the following considerations is paramount due to altered physiology?

Answer 37

Long term opioid use leads to cross-tolerance to other CNS depressants. This may manifest as a decreased analgesic effect from inhaled anesthetics. Conversely acute opioid administration decreases anesthetic requirements.

Question 38

A patient presents for emergency surgery under general anesthesia after a suspected barbiturate overdose. Considering the pathophysiological effects of barbiturates on CNS depression, which of the following is a critical consideration for anesthesia management in this patient?

Answer 38

No specific pharmacologic antagonist exists to reverse this barbiturate-induced CNS depression, and the use of nonspecific stimulants is not encouraged. Depression of ventilation may be profound. Maintenance of a patent airway, protection from aspiration, and support of ventilation using a cuffed endotracheal tube are often necessary. Barbiturate overdose may also be associated with hypotension because of central vasomotor depression, direct myocardial depression, and increased venous capacitance. This hypotension usually responds to fluid infusion, although occasionally vasopressors or inotropic drugs are required. Hypothermia is frequent. Acute renal failure resulting from hypotension and rhabdomyolysis may occur.

Question 39

In a patient with a history of long-term barbiturate use scheduled for elective surgery, which of the following represents an essential component of perioperative care to address potential withdrawal symptoms?

Answer 39

Barbiturate withdrawal manifests initially as anxiety, skeletal muscle tremors, hyperreflexia, diaphoresis, tachycardia, and orthostatic hypotension. Cardiovascular collapse and hyperthermia may occur.
The most serious problem associated with barbiturate withdrawal is the occurrence of grand mal seizures which are difficult to abort once they develop. Pentobarbital may be administered to treat barbiturate withdrawal. Phenobarbital and benzodiazepines are also useful (book, p. 636).

Question 40

For a patient on long-term benzodiazepine therapy presenting for surgery, which of the following anesthesia-related adjustments should be considered based on the pharmacological and pathophysiological effects of benzodiazepines?

Answer 40

Tolerance and physical dependence occur with long-term benzodiazepine use as they do with barbiturate use and can lead to cross-tolerance to other CNS depressants; patients may need higher doses (book, pg. 636).

Question 41

In a patient with a history of chronic amphetamine use undergoing surgery, which pathophysiological consideration is most relevant for anesthesia management?

Answer 41

Decreased sensitivity to the effects of sympathomimetic anesthetics due to chronic catecholamine depletion.

Question 42

A patient with a history of long-term cannabis use is undergoing elective surgery. Given the known effects of cannabis on the cardiovascular system, which of the following anesthesia management considerations is most pertinent?

Answer 42

The most consistent cardiac change is an increased resting heart rate. -Orthostatic hypotension may occur -Decreased dose requirements for volatile anesthetics

Question 43

Considering the pharmacological effects of cannabis, particularly THC, on the CNS and its implications for anesthesia, which of the following is a critical consideration for determining anesthetic dosing in patients with a history of cannabis use?

Answer 43

Decreased dose requirements for volatile anesthetics -potentiate respiratory depression w/ opioids

Question 44

A 45-year-old patient is scheduled for emergency surgery and has a history of recent acetaminophen overdose. Considering the pathophysiological impact of acetaminophen on hepatic function, which of the following anesthetic management strategies is most appropriate?

Answer 44

Careful selection and titration of anesthetic agents to account for potentially impaired hepatic metabolism due to centrilobular hepatic necrosis.

Question 45

In the perioperative management of a patient recovering from acetaminophen-induced hepatotoxicity, which intervention is paramount to mitigate the risk of further liver damage and ensure safe anesthesia?

Answer 45

Administration of N-Acetylcysteine in the perioperative period to continue supporting glutathione synthesis and hepatic recovery.

Question 46

A 55-year-old pesticide factory worker is admitted to the emergency room with severe organophosphate poisoning, manifesting as bronchorrhea and respiratory muscle paralysis. Considering the pathophysiological impact of organophosphate on respiratory function, which advanced airway management technique is most appropriate to prevent hypoxemia and support ventilation?

Answer 46

Intubation with mechanical ventilation

Question 47

During elective surgery, a patient with a recent history of organophosphate poisoning exhibits cholinergic symptoms under anesthesia. Which anesthetic management strategy is most appropriate to mitigate the effects of residual organophosphate toxicity?

Answer 47

Administration of intravenous atropine to counteract muscarinic overstimulation during anesthesia.

Question 48

In the treatment of a patient with acute organophosphate poisoning, why is the administration of pralidoxime alongside atropine critical for anesthetic management during emergency surgery?

Answer 48

Pralidoxime reactivates acetylcholinesterase by removing organophosphate from the enzyme, restoring neuromuscular junction function and reducing the risk of paralysis.

Question 49

For a patient with organophosphate poisoning exhibiting significant bronchorrhea and respiratory distress, what is the rationale behind combining atropine and mechanical ventilation in the acute management phase?

Answer 49

Atropine is targeted for the muscarinic effects of organophosphate poisoning. Mechanical ventilation will ensure ventilation/perfusion to offset acute resp failure that can occur due to resp m and diaphragmatic weakness of paralysis, or inhibition of medullary respiratory center.

Question 50

A patient with suspected carbon monoxide (CO) poisoning is scheduled for emergency surgery. Given the pathophysiological effects of CO on oxygen delivery, which of the following anesthetic strategies is most critical to optimize tissue oxygenation?

Answer 50

Administration of 100% oxygen to displace CO from hemoglobin and facilitate its elimination.

Question 51

In the perioperative care of a patient recovering from CO poisoning, which monitoring strategy is most appropriate to detect early signs of CO-induced cardiac toxicity?

Answer 51

Continuous cardiac monitoring; cardiac dysrhythmias and pulmonary edema may occur from increased cardiac output

Question 52

A pregnant patient at 32 weeks gestation, presenting with carbon monoxide (CO) poisoning, requires an emergency cesarean section. Given the pathophysiological challenges of CO’s high affinity for fetal hemoglobin and its slow elimination from the fetal circulation, which advanced anesthetic management strategy is paramount to optimize fetal oxygenation and mitigate the effects of CO toxicity?

Answer 52

Hyperbaric oxygen therapy is indicated in patients who are pregnant and have HbCO concentration above 15%.