Fentanyl-induced rigidity during emergence from general anesthesia potentiated by venlafexine

A case of opioid-induced rigidity requiring naloxone administration at the time of anesthesia emergence

BACKGROUND

Opioid-induced rigidity is typically observed during rapid administration of fentanyl. Herein, we present a case in which rigidity occurred after reversal of rocuronium during emergence from anesthesia.

CASE PRESENTATION

A 73-year-old man underwent video-assisted partial lung resection. General anesthesia was induced with propofol, remimazolam, remifentanil, and rocuronium. Fentanyl was administered early during anesthesia. The surgery was completed without complications, and sugammadex sodium was administered for rocuronium reversal. The patient became agitated, but spontaneous breathing was maintained; therefore, the intratracheal tube was removed after the administration of flumazenil. The patient developed stiffness in the neck and jaw muscles along with remarkable skeletal muscle contractions. Dramatic improvement was observed immediately after administration of naloxone.

CONCLUSIONS

Even as the simulated effect site concentration of fentanyl decreases during anesthesia emergence, opioid-induced rigidity may still occur. Rapid reversal of remimazolam by flumazenil might have contributed to the rigidity in this case.

Catatonia and Opioid Withdrawal: A Case Report

In this case report, we present an 82-year-old female who was diagnosed with catatonia after she exhibited immobility, mutism, withdrawal, and stereotypy during a hospitalization for altered mental status. Fentanyl was found in her urine toxicology, and it was later discovered that she had been taking non-prescription pills from Mexico that were likely the source of the fentanyl. Her catatonia quickly remitted with benzodiazepine treatment. This case underscores previously unknown risks of substance use, which has grown especially important to psychiatric care considering how rampant the opioid epidemic has become. More so, these risks extend beyond opioid use disorders since other non-prescription drugs are commonly laced with fentanyl. Not only does this education need to be given to providers and patients alike, but further research should be conducted to establish and quantify the risk of catatonia with opioid withdrawal.

Quantification of muscle tone by using shear wave velocity during an anaesthetic induction: a prospective observational study

OBJECTIVES

The quantitative assessment of muscle stiffness or weakness is essential for medical care. Shear wave elastography is non-invasive ultrasound method and provides quantitative information on the elasticity of soft tissue. However, the universal velocity scale for quantification has not been developed. The aim of the study is to determine the shear wave velocities of abdominal muscle during anesthetic induction and to identify methods to cancel the effects of confounders for future development in the quantitative assessment of muscle tone using the universal scale.

METHODS

We enrolled 75 adult patients undergoing elective surgery with ASA-PS I - III in the period between December 2018 and March 2021. We measured and calculated the shear wave velocity (SWV) before and after opioid administration (i.e., the baseline at rest and opioid-induced rigidity condition), and after muscle relaxant administration (i.e., zero reference condition). The SWV value was adjusted for the subcutaneous fat thickness by our proposed corrections. The SWVs after the adjustment were compared among the values in baseline, rigidity, and relaxation using one-way repeated-measures ANOVA and post hoc Tukey-Kramer test. A p-value of < 0.05 was considered to be statistically significant. UMIN Clinical Trials Registry identifier UMIN000034692, registered on October 30, 2018.

RESULTS

The SWVs in the baseline, opioid-induced rigidity, and muscle relaxation conditions after the adjustment were 2.08 ± 0.48, 2.41 ± 0.60, and 1.79 ± 0.30 m/s, respectively (p < 0.001 at all comparisons).

CONCLUSION

The present study suggested that the SWV as reference was 1.79 m/s and that the SWVs at rest and opioid-induced rigidity were ~ 10% and ~ 30% increase from the reference, respectively. The SWV adjusted for the subcutaneous fat thickness may be scale points for the assessment of muscle tone.

Postoperative Catatonia After Fentanyl, Hydromorphone, and Ketamine Administration in a Patient Taking Sertraline: A Case Report

Opioid-induced catatonia is underrecognized and poorly understood in the literature. An 81-year-old woman with chronic kidney disease stage III taking sertraline underwent surgery with general anesthesia, receiving fentanyl, hydromorphone, and ketamine. Postoperatively, she was unresponsive, rigid, and cataleptic with pinpoint pupils. Symptoms resolved with a naloxone infusion suggesting opioid-induced catatonia as the leading diagnosis. Differential diagnoses and etiologies discussed reveal a possible multifactorial catatonia mechanism involving opioids, ketamine, and serotonin. Anesthesiologists should consider these potential interactions when using opioids for management of vulnerable patients.

Fentanyl-induced muscle rigidity in a dog during weaning from mechanical ventilation after emergency abdominal surgery: A case report

A 22.5-kg, 8.4-year-old female mixed breed dog was presented for an emergency ovariohysterectomy for pyometra. No neurological abnormalities were observed on preoperative physical examination. Surgery was completed uneventfully under fentanyl- and sevoflurane-based anaesthesia. Cardiorespiratory indices remained stable under mechanical ventilation throughout the procedure. Approximately 23 min after the discontinuation of fentanyl infusion, the investigator noticed jaw closure and stiffness and thoraco-abdominal muscle rigidity. To rule out fentanyl-induced muscle rigidity, naloxone was administered. Following administration of naloxone, there was a return of spontaneous respiratory effort, indicated by capnogram and visible chest wall excursion. Based on the clinical signs and response to naloxone administration, the dog was diagnosed with suspected fentanyl-induced muscle rigidity. Six minutes after the return of spontaneous respiration, the dog was extubated uneventfully without additional naloxone administration. During 4 days of postoperative hospitalization, no recurrent muscle rigidity was observed, and the patient was discharged safely. The total dose of fentanyl administered was 0.61 mg (27 μg kg^-1 ).

New Serotonin-Norepinephrine Reuptake Inhibitors and Their Anesthetic and Analgesic Considerations

Serotonin-norepinephrine reuptake inhibitors (SNRIs) inhibit the presynaptic neuronal uptake of serotonin and norepinephrine and prolong the effects of the monoamines in the synaptic cleft within the central nervous system, leading to increased postsynaptic receptor activation and neuronal activities. Serotonin-norepinephrine reuptake inhibitors can have multiple clinical indications, including as the first-line agents for the management of depression and anxiety, and as analgesics in the treatment of chronic pain. The effects of reuptake inhibition of norepinephrine and serotonin are often dose-dependent and agent-dependent. There are five FDA-approved serotonin-norepinephrine reuptake inhibitors (desvenlafaxine, duloxetine, levomilnacipran, milnacipran and sibutramine) currently being marketed in the United States. As the COVID-19 pandemic significantly increased the incidence and prevalence of anxiety and depression across the country, there are significantly increased prescriptions of these medications perioperatively. Thus, anesthesiologists are more likely than ever to have patients administered with these agents and scheduled for elective or emergency surgical procedures. A thorough understanding of these commonly prescribed serotonin-norepinephrine reuptake inhibitors and their interactions with commonly utilized anesthetic agents is paramount. There are two potentially increased risks related to the continuation of SNRIs through the perioperative period: intraoperative bleeding and serotonin syndrome. SNRIs have some off-label uses, more new indications, and ever-increasing new applications in perioperative practice. This article aims to review the commonly prescribed serotonin-norepinephrine reuptake inhibitors and the current clinical evidence regarding their considerations in perioperative anesthesia and analgesia.

Objective Characterization of Opiate-Induced Chest Wall Rigidity

Introduction

Opiate-induced chest wall rigidity is a syndrome that largely goes unrecognized. To date, no study has presented significant objective data to better understand this syndrome.

Objective

The aim of this study was to explore the correlation between the dosage of opiates and the incidence of chest wall rigidity, ventilatory changes, and effects of naloxone administration.

Methods

A total of eight patients were identified as having episodes of chest wall rigidity, with half of the population being females, with an average age of 54.8 ± 9 years. Physiological changes, ventilator data, vitals, and opiate dosage prior to chest wall rigidity episodes and after reversal with naloxone administration were analyzed using the Wilcoxon rank sum test for statistical significance.

Results

Significant changes were observed in dynamic wall compliance without positive end-expiratory pressure (PEEP) (pre-median=5.13; post-median=52.03; p=0.0078), dynamic wall compliance with PEEP (pre-median=6.13; post-median=72.36; p=0.0078), tidal volume (pre-median=110.5; post-median=1006; p=0.0078), and ventilator airflow (pre-median=0; post-median=75; p=0.0078). However, no statistically significant changes were detected in end tidal CO₂ (pre-median=36; post-median=37.5; p=0.4219), respiratory rate (pre-median=9; post-median=10.5; p=0.7188), or peak airway pressure (pre-median=17; post-median=21.5; p=0.4063). Additionally, there is a statistically significant correlation between morphine equivalent potency dosing within 24 hours and the change in tidal volume (r=0.8237; p=0.0439).

Conclusions

Our study is the first to demonstrate significant objective data on the ventilatory responses seen with opiate-induced chest wall rigidity. These findings may assist clinicians in better understanding the presentation and management of chest wall rigidity.

The anaesthetist, opioid analgesic drugs, and serotonin toxicity: a mechanistic and clinical review

Most cases of serotonin toxicity are provoked by therapeutic doses of a combination of two or more serotonergic drugs, defined as drugs affecting the serotonin neurotransmitter system. Common serotonergic drugs include many antidepressants, antipsychotics, and opioid analgesics, particularly fentanyl, tramadol, meperidine (pethidine), and methadone, but rarely morphine and other related phenanthrenes. Symptoms of serotonin toxicity are attributable to an effect on monoaminergic transmission caused by an increased synaptic concentration of serotonin. The serotonin transporter (SERT) maintains low serotonin concentrations and is important for the reuptake of the neurotransmitter into the presynaptic nerve terminals. Some opioids inhibit the reuptake of serotonin by inhibiting SERT, thus increasing the plasma and synaptic cleft serotonin concentrations that activate the serotonin receptors. Opioids that are good inhibitors of SERT (tramadol, dextromethorphan, methadone, and meperidine) are most frequently associated with serotonin toxicity. Tramadol also has a direct serotonin-releasing action. Fentanyl produces an efflux of serotonin, and binds to 5-hydroxytryptamine (5-HT)_1A and 5-HT_2A receptors, whilst methadone, meperidine, and more weakly tapentadol, bind to 5-HT_2A but not 5-HT_1A receptors. The perioperative period is a time where opioids and other serotonergic drugs are frequently administered in rapid succession, sometimes to patients with other serotonergic drugs in their system. This makes the perioperative period a relatively risky time for serotonin toxicity to occur. The intraoperative recognition of serotonin toxicity is challenging as it can mimic other serious syndromes, such as malignant hyperthermia, sepsis, thyroid storm, and neuroleptic malignant syndrome. Anaesthetists must maintain a heightened awareness of its possible occurrence and a readiness to engage in early treatment to avoid poor outcomes.

Changing risk and presentation of overdose associated with consumption of street drugs at a supervised injection site in Vancouver, Canada

BACKGROUND

British Columbia is experiencing a public health emergency due to overdoses resulting from consumption of street drugs contaminated with fentanyl. While the risk of overdoses appears to be increasing, the overdose rate and severity of overdose presentations have yet to be quantified.

METHODS

Insite is a supervised injection site in Vancouver. Data from Insite's client database from January 2010 to June 2017 were used to calculate overdose rates as well as the proportion of overdoses involving rigidity and naloxone administration over time in order to estimate changes in the risk and severity of overdose resulting from changes in the local drug supply.

RESULTS

The overdose rate increased significantly for all drug categories. Heroin used alone or with other drugs continues to be associated with the highest overdose rate. The overdose rate associated with heroin increased from 2.7/1000 visits to 13/1000 visits over the study period, meaning that clients were 4.8 times more likely to overdose in the most recent period as in the baseline period. The proportion of overdose events involving rigidity, a known complication of intravenous fentanyl use, increased significantly from 10.4% to 18.9%. The proportion of overdoses requiring naloxone administration increased significantly from 48.4% to 57.1% and is now similar across all drug categories.

CONCLUSIONS

The risk and severity of overdoses at Insite have increased since the emergence of illicit fentanyl. This information derived from supervised injection site data can be used to inform local harm reduction efforts and the response to the overdose emergency.

Neuroleptic malignant syndrome and serotonin syndrome

The clinical manifestation of drug-induced abnormalities in thermoregulation occurs across a variety of drug mechanisms. The aim of this chapter is to review two of the most common drug-induced hyperthermic states, serotonin syndrome and neuroleptic malignant syndrome. Clinical features, pathophysiology, and treatment strategies will be discussed, in addition to differentiating between these two syndromes and differentiating them from other hyperthermic or febrile syndromes. Our goal is to both review the current literature and to provide a practical guide to identification and treatment of these potentially life-threatening illnesses. The diagnostic and treatment recommendations made by us, and by other authors, are likely to change with a better understanding of the pathophysiology of these syndromes.

Fentanyl-induced chest wall rigidity syndrome in a routine bronchoscopy

Combination of sedatives such as fentanyl and midazolam during bronchoscopy is recommended by American College of Chest Physician due to its favourable drug profile. It improves patient comfort and tolerance, and is commonly given unless contraindicated. We describe a rare case of fentanyl-induced chest wall rigidity syndrome during a routine bronchoscopy with endobronchial ultrasound guided-transbronchial needle aspiration (EBUS-TBNA) in a 55 year old male presenting with a lung mass and mediastinal lymphadenopathy. This was effectively managed with neuromuscular blockade, intubation and reversal agents including naloxone. This rare complication should be effectively managed by all bronchoscopist as it carries significant mortality and morbidity if not recognised early. We review the literature on the occurrence of fentanyl-induced chest wall rigidity and its predisposing risks factors.

Delayed emergence after anesthesia

In most instances, delayed emergence from anesthesia is attributed to residual anesthetic or analgesic medications. However, delayed emergence can be secondary to unusual causes and present diagnostic dilemmas. Data from clinical studies is scarce and most available published material is comprised of case reports. In this review, we summarize and discuss less common and difficult to diagnose reasons for delayed emergence and present cases from our own experience or reference published case reports/case series. The goal is to draw attention to less common reasons for delayed emergence, identify patient populations that are potentially at risk and to help anesthesiologists identifying a possible cause why their patient is slow to wake up.

Malignant hyperthermia in Brazil: analysis of hotline activity in 2009

BACKGROUND AND OBJECTIVES

Malignant hyperthermia (MH) is a pharmacogenetic disease that causes abnormal hypermetabolic reaction to halogenated anesthetics and/or depolarizing muscle relaxants. In Brazil, there is a hotline telephone service for MH since 1991, available 24 hours a day in São Paulo. This article analyzes the activity of the Brazilian hotline service for MH in 2009.

METHODS

Prospective analysis of all phone calls made to the Brazilian hotline service for MH from January to December 2009.

RESULTS

Twenty-two phone calls were received: 21 from the South/Southeast region of Brazil and one from the North region. Fifteen calls were requests for general information about MH. Seven were about suspected MH acute episodes, two of which were not considered as MH. In five episodes compatible with MH, all patients received halogenated volatile anesthetics (2, isoflurane; 3, sevoflurane) and one also used succinylcholine; there were four men and one woman, with a mean age of 18 years (2-27). The problems described in the five MH episodes were tachycardia (5), increased expired carbon dioxide (4), hyperthermia (3), acidemia (1), rhabdomyolysis (1), and myoglobinuria (1). One patient received dantrolene. All five patients with MH episodes were follow-up in the intensive care unit and recovered without sequelae. Susceptibility to MH was later confirmed in two patients by in vitro muscle contracture test.

CONCLUSIONS

The number of calls per year in the Brazilian hotline service for MH is still low. The characteristics of MH episode were similar to those reported in other countries. The knowledge of MH in Brazil needs to be increased.

[Perioperative adverse events related to antidepressive agents use]

OBJECTIVE

Depression is the most common psychiatric disease, which is treated by the use of antidepressive agents possessing various mechanisms of action. Thus, the use in preoperative period of antidepressive agents is frequent (7% of patients scheduled for surgery). The objective of this review was to update the knowledge on the drug interactions between antidepressive agents and drugs used in perioperative period.

METHODS

(i) Medline and Ovid databases using combination of antidepressive agent and perioperative period as keywords; (ii) national and European epidemiologic database; (iii) expert recommendation and official French health agency; (iv) reference book chapters.

RESULTS

The clinical practice showed a limited risk of adverse event related to antidepressant agents interaction with perioperative used drugs. In the two past decades, few relevant observations of adverse event related with imipramine and monoamine oxidase inhibitors use was reported. The most recent antidepressive agents had no serious adverse interaction. Nevertheless, the serotonin syndrome has to be known as far as it is more and more reported. In case of hypotension, the use of vasopressive agent has to be careful because of excessive response.

Masseter muscle rigidity: Atypical malignant hyperthermia presentation or isolated event?

This report describes a case of masseter muscle rigidity encountered at the start of an elective gynaecological procedure. At preoperative assessment, the patient, a 41-year old woman with a previous non-eventful surgical and anesthetic history was given a Mallampati score of 3. Following suxamethonium administration, full mouth opening proved difficult. Laryngoscopy and tracheal intubation were not possible leading to the eventual use of a laryngeal mask airway and resulting in a successful anaesthetic outcome. A number of possibilities that may account for this situation as well as viable options for airway access in such cases are discussed below.

Fentanyl-induced bradykinesia and rigidity after deep brain stimulation in a patient with Parkinson disease

A 58-year-old man with advanced Parkinson disease underwent battery replacement for a deep brain stimulator and experienced severe bradykinesia and rigidity postoperatively for 36 hours. The patient was administered fentanyl as an anesthetic during the procedure and as an analgesic periodically during the day after surgery. The severe bradykinesia and rigidity persisted despite reactivation of the deep brain stimulator and immediate reinstitution of Parkinson disease medications, but resolved completely several hours after discontinuation of fentanyl.

Drug-induced serotonin syndrome: a review

Serotonin syndrome, or serotonin toxicity (ST), is a clinical condition that occurs as a result of an iatrogenic drug-induced increase in intrasynaptic serotonin levels primarily resulting in activation of serotonin(2A) receptors in the central nervous system. The severity of symptoms spans a spectrum of toxicity that correlates with the intrasynaptic serotonin concentration. Although numerous drugs have been implicated in ST, life-threatening cases generally occur only when monoamine oxidase inhibitors are combined with either selective or nonselective serotonin re-uptake inhibitors. The triad of clinical features consists of neuromuscular hyperactivity, autonomic hyperactivity and altered mental status, which may present abruptly and progress rapidly. The awareness of ST is crucial not only in avoiding the unintentional lethal combination of therapeutic drugs but also in recognizing the clinical picture when it occurs so that treatment can be promptly initiated. In this review, the pathophysiology, clinical features, implicated drugs, diagnosis and treatment of ST are discussed.

Psychotropic Drugs and the Perioperative Period: A Proposal for a Guideline in Elective Surgery

Evidence-based guidelines for the perioperative management of psychotropic drugs are lacking. The level of evidence is low and is based on case reports, open trials, and non-systematic reviews. However, the interactions and effects mentioned indicate that patients who use psychotropics and require surgery have an enhanced perioperative risk. A group of clinicians from several clinical disciplines determined which risks should be considered in an integrated preoperative assessment, as well as how psychotropics might interfere with these risks. The risks that should be considered in the perioperative period are the extent of the surgery, the patient's physical state, anesthesia, the direct and indirect (Phase I and II) effects of psychotropics, risk of withdrawal symptoms, and risk of psychiatric recurrence or relapse. Because of new drug developments, the risk of interactions increases. The literature has not provided articles that systematically address these risks. On the basis of a systematic analysis of the available literature guided by the formulated perioperative risks, a proposal for the perioperative management of psychotropics was formulated. Patients who use lithium, monoamine oxidase inhibitors, tricyclics, and clozepine have serious drug-drug interactions, with increased physical risks, including withdrawal, and therefore qualify for American Society of Anesthesiologists (ASA) Classification 3. From the perspective of the physical risk, they require discontinuation. However, from the perspective of the risk of withdrawal and psychiatric relapse and recurrence, these patients deserve intensive, integrated anesthetic/psychiatric management. For patients on selective serotonin reuptake inhibitors (SSRIs) who are mentally and physical stable (ASA Classification 2), the risk of withdrawal seems to justify their continuation. Yet, patients on SSRIs with higher physical or psychiatric risks should be seen in consultation. Both the physical and psychiatric risks of patients who use antipsychotics and other antidepressants should be regarded as enhanced. From a physical perspective, they qualify for ASA Classification 2. From the perspective of withdrawal and psychiatric recurrence or relapse, they should be seen by (their) psychiatrists. Preoperative assessment clinics offer the opportunity to assess and evaluate these risks in order to deliver patient-tailored integrated care. Authors propose a model for quality management.

Conduite à tenir concernant le traitement médicamenteux des patients adressés pour chirurgie programmée

This review focuses on potential drug interactions between anaesthetic drugs or techniques and chronic medications in patients scheduled for surgery. The vast majority of therapeutics can be continued until the morning of surgery. However, for some drugs such as ACE inhibitors, there is strong evidence to recommend their discontinuation prior to surgery. When juged necessary, interruption of chronic therapeutic needs to be anticipated and planned. In the other hand, for other drugs such as beta-blockers or L-Dopa, acute withdrawal is associated with documented adverse outcome. As a result, such drugs have to be continuing throughout the operative period. Although a general consensus exists for many medications, there are still controverses as to the management of antithrombotic drugs and some central nervous system agents. Advances in anaesthesia include knowledge on the mechanisms involved in drug interactions, which allows us to improve the preoperative management of chronic therapeutics.

Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity

Toxicity resulting from excessive intra-synaptic serotonin, historically referred to as serotonin syndrome, is now understood to be an intra-synaptic serotonin concentration-related phenomenon. Recent research more clearly delineates serotonin toxicity as a discreet toxidrome characterized by clonus, hyper-reflexia, hyperthermia and agitation. Serotonergic side-effects occur with serotonergic drugs, and overdoses of serotonin re-uptake inhibitors (SRIs) frequently produce marked serotonergic side-effects, and in 15% of cases, moderate serotonergic toxicity, but not to a severe degree, which produces hyperthermia and risk of death. It is only combinations of serotonergic drugs acting by different mechanisms that are capable of raising intra-synaptic serotonin to a level that is life threatening. The combination that most commonly does this is a monoamine oxidase inhibitor (MAOI) drug combined with any SRI. There are a number of lesser-known drugs that are MAOIs, such as linezolid and moclobemide; and some opioid analgesics have serotonergic activity. These properties when combined can precipitate life threatening serotonin toxicity. Possibly preventable deaths are still occurring. Knowledge of the properties of these drugs will therefore help to ensure that problems can be avoided in most clinical situations, and treated appropriately (with 5-HT(2A) antagonists for severe cases) if they occur. The phenylpiperidine series opioids, pethidine (meperidine), tramadol, methadone and dextromethorphan and propoxyphene, appear to be weak serotonin re-uptake inhibitors and have all been involved in serotonin toxicity reactions with MAOIs (including some fatalities). Morphine, codeine, oxycodone and buprenorphine are known not to be SRIs, and do not precipitate serotonin toxicity with MAOIs.

Anaesthesia for patients with mood disorders

PURPOSE OF REVIEW

Treatment of patients with mood disorders has changed over the past few years. It is not always clear how the anaesthesiologist has to incorporate these antidepressants and mood stabilizers in premedication or even how to anticipate any interaction with anaesthetic technique.

RECENT FINDINGS

The older generation of antidepressants (tricyclic antidepressants, monoamine oxidase inhibitors) is seldom used nowadays. Actually, treatment with selective serotonin-reuptake inhibitors, serotonin noradrenaline-reuptake inhibitors, noradrenaline-reuptake inhibitor, noradrenergic and specific serotonin antidepressants, or noradrenaline- and dopamine-reuptake inhibitors is common practice. Combination with atypical antipsychotics and newer antiepileptics is suggested as an add-on therapy or as monotherapy, while lithium and valproate therapy is still the first choice in bipolar mood stabilization. Electroconvulsive therapy is still used in therapy-resistant forms of depression; however, the anaesthesia technique herein has been increasingly well described in the last years. Electroencephalogram-derived monitoring such as bispectral index (BIS) can be used as a tool to predict seizure duration. Intoxications with these newer agents are not infrequent and deserve specific attention. In particular, serotonin syndrome is a life-threatening condition that requires great care by the anaesthesiologist. The chronic use of antidepressants does affect the anaesthetized patient: hypotension, arrhythmias, changed thermoregulation, altered postoperative pain, differences in surgical stress response and postoperative confusion. However, it is advised to continue these drugs in the perioperative period.

SUMMARY

Discontinuation of treatment with the new antidepressants in the perioperative period is not advised. Intoxication with the newer drugs appears to be safer. The anaesthesiologist must pay attention to serotonin syndrome. Electroconculsive therapy has gained renewed attention.