Upper Airway Collapsibility during Dexmedetomidine and Propofol Sedation in Healthy Volunteers: A Nonblinded Randomized Crossover Study

Opioid-free general anesthesia: considerations, techniques, and limitations

PURPOSE OF REVIEW

To discuss the role of opioids during general anesthesia and examine their advantages and risks in the context of clinical practice. We define opioid-free anesthesia (OFA) as the absolute avoidance of intraoperative opioids.

RECENT FINDINGS

In most minimally invasive and short-duration procedures, nonopioid analgesics, analgesic adjuvants, and local/regional analgesia can significantly spare the amount of intraoperative opioid needed. OFA should be considered in the context of tailoring to a specific patient and procedure, not as a universal approach. Strategies considered for OFA involve several adjuncts with low therapeutic range, requiring continuous infusions and resources, with potential for delayed recovery or other side effects, including increased short-term and long-term pain. No evidence indicates that OFA leads to decreased long-term opioid-related harms.

SUMMARY

Complete avoidance of intraoperative opioids remains questionable, as it does not necessarily ensure avoidance of postoperative opioids. Multimodal analgesia including local/regional anesthesia may allow OFA for selected, minimally invasive surgeries, but further research is necessary in surgeries with high postoperative opioid requirements. Until there is definitive evidence regarding procedure and patient-specific combinations as well as the dose and duration of administration of adjunct agents, it is imperative to practice opioid-sparing approach in the intraoperative period.

Acute Respiratory Failure Secondary to Low-Dose Opioid Administration in a Patient With Obstructive Sleep Apnea and Obesity Hypoventilation Syndrome After Undergoing Trans-sphenoidal Tumor Resection

We present a case of an obese 56-year-old male with obstructive sleep apnea (OSA), obesity hypoventilation syndrome (OHS), and pituitary macroadenoma, who underwent nasal endoscopic trans-sphenoidal resection. Surgery was performed under general anesthesia, uneventfully as planned. The patient experienced, however, delayed emergence despite receiving adequate neuromuscular blockade agent reversal. Extubation was performed and the patient was transferred to the recovery room on a Venturi mask (50% fraction of inspired oxygen, FIO2)and 93% saturation. Postoperatively, the patient was complaining of acute pain that did not resolve with non-opioid medications and a low morphine dose (0.035 mg/kg) for pain management was administered. Subsequently, he developed severe respiratory depression, requiring intubation. After three hours, the patient was extubated, transferred to the intensive care unit, and discharged five days later. Although the patient recovered favorably, this case highlights the risks of administering opioids to patients with OSA and OHS. To our knowledge, this is the first case reporting extreme respiratory depression secondary to the administration of a very low dose of morphine in patients with these comorbidities. Therefore, it is essential to be cautious with the use of opioids and to explore multimodal pain relief methods for these patients.

The Modulation by Anesthetics and Analgesics of Respiratory Rhythm in the Nervous System

Rhythmic eupneic breathing in mammals depends on the coordinated activities of the neural system that sends cranial and spinal motor outputs to respiratory muscles. These outputs modulate lung ventilation and adjust respiratory airflow, which depends on the upper airway patency and ventilatory musculature. Anesthetics are widely used in clinical practice worldwide. In addition to clinically necessary pharmacological effects, respiratory depression is a critical side effect induced by most general anesthetics. Therefore, understanding how general anesthetics modulate the respiratory system is important for the development of safer general anesthetics. Currently used volatile anesthetics and most intravenous anesthetics induce inhibitory effects on respiratory outputs. Various general anesthetics produce differential effects on respiratory characteristics, including the respiratory rate, tidal volume, airway resistance, and ventilatory response. At the cellular and molecular levels, the mechanisms underlying anesthetic-induced breathing depression mainly include modulation of synaptic transmission of ligand-gated ionotropic receptors (e.g., γ-aminobutyric acid, N-methyl-D-aspartate, and nicotinic acetylcholine receptors) and ion channels (e.g., voltage-gated sodium, calcium, and potassium channels, two-pore domain potassium channels, and sodium leak channels), which affect neuronal firing in brainstem respiratory and peripheral chemoreceptor areas. The present review comprehensively summarizes the modulation of the respiratory system by clinically used general anesthetics, including the effects at the molecular, cellular, anatomic, and behavioral levels. Specifically, analgesics, such as opioids, which cause respiratory depression and the "opioid crisis", are discussed. Finally, underlying strategies of respiratory stimulation that target general anesthetics and/or analgesics are summarized.

Pain management after cardiac surgery via median sternotomy: A systematic review with procedure-specific postoperative pain management (PROSPECT) recommendations

BACKGROUND

Pain after cardiac surgery via median sternotomy can be difficult to treat, and if inadequately managed can lead to respiratory complications, prolonged hospital stays and chronic pain.

OBJECTIVES

To evaluate available literature and develop recommendations for optimal pain management after cardiac surgery via median sternotomy.

DESIGN

A systematic review using PROcedure-SPECific Pain Management (PROSPECT) methodology.

ELIGIBILITY CRITERIA

Randomised controlled trials and systematic reviews published in the English language until November 2020 assessing postoperative pain after cardiac surgery via median sternotomy using analgesic, anaesthetic or surgical interventions.

DATA SOURCES

PubMed, Embase and Cochrane Databases.

RESULTS

Of 319 eligible studies, 209 randomised controlled trials and three systematic reviews were included in the final analysis. Pre-operative, intra-operative and postoperative interventions that reduced postoperative pain included paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), intravenous magnesium, intravenous dexmedetomidine and parasternal block/infiltration.

CONCLUSIONS

The analgesic regimen for cardiac surgery via sternotomy should include paracetamol and NSAIDs, unless contraindicated, administered intra-operatively and continued postoperatively. Intra-operative magnesium and dexmedetomidine infusions may be considered as adjuncts particularly when basic analgesics are not administered. It is not clear if combining dexmedetomidine and magnesium would provide superior pain relief compared with either drug alone. Parasternal block/surgical site infiltration is also recommended. However, no basic analgesics were used in the studies assessing these interventions. Opioids should be reserved for rescue analgesia. Other interventions, including cyclo-oxygenase-2 specific inhibitors, are not recommended because there was insufficient, inconsistent or no evidence to support their use and/or due to safety concerns.

Adjuvants for balanced anesthesia in ambulatory surgery

Balanced anesthesia relies on the simultaneous administration of different drugs to attain an anesthetic state. The classic triad of anesthesia is a combination of a hypnotic, an analgesic, and a neuromuscular blocker. It is predominantly the analgesic pillar of this triad that became more and more supported by adjuvant therapy. The aim of this approach is to evolve into an opioid-sparing technique to cope with undesirable side effects of the opioids and is fueled by the opioid epidemic. The optimal strategy for balanced general anesthesia in ambulatory surgery must aim for a transition to a multimodal analgesic regimen dealing with acute postoperative pain and ideally reduce the most common adverse effects patients are faced with at home; sore throat, delayed awakening, memory disturbances, headache, nausea and vomiting, and negative behavioral changes. Over the years, this continuum of "multimodal general anesthesia" adopted many drugs with different modes of action. This review focuses on the most recent evidence on the different adjuvants that entered clinical practice and gives an overview of the different mechanisms of action, the potential as opioid-sparing or hypnotic-sparing drugs, and the applicability specifically in ambulatory surgery.

Usefulness of new acoustic respiratory sound monitoring with artificial intelligence for upper airway assessment in obese patients during monitored anesthesia care

Monitored anesthesia care (MAC) often causes airway complications, particularly posing an elevated risk of aspiration and airway obstruction in obese patients. This study aimed to quantify the levels of aspiration and airway obstruction using an artificial intelligence (AI)-based acoustic analysis algorithm, assessing its utility in identifying airway complications in obese patients. To verify the correlation between the stridor quantitative value (STQV) calculated by acoustic analysis and body weight, and to further evaluate fluid retention and airway obstruction, STQV calculated exhaled breath sounds collected at the neck region, was compared before and after injection of 3 ml of water in the oral cavity and at the start and end of the MAC procedures. STQV measured immediately following the initiation of MAC exhibited a weak correlation with body mass index. Furhtermore, STQV values before and after water injection increased predominantly after injection, further increased at the end of MAC. AI-based analysis of cervical respiratory sounds can enhance the safety of airway management during MAC by quantifying airway obstruction and fluid retention in obese patients. J. Med. Invest. 70 : 430-435, August, 2023.

Evaluation of patient state index, bispectral index, and entropy during drug induced sleep endoscopy with dexmedetomidine

Multiple electroencephalographic (EEG) monitors and their associated EEG markers have been developed to aid in assessing the level of sedation in the operating room. While many studies have assessed the response of these markers to propofol sedation and anesthetic gases, few studies have compared these markers when using dexmedetomidine, an alpha-2 agonist. Fifty-one patients underwent drug induced sleep endoscopy with dexmedetomidine sedation. Continuous EEG was captured using SedLine (Masimo, Inc), and a playback system was used to extract the bispectral index (BIS) (Medtronic Inc), the patient state index (PSI) (Masimo, Inc), the state and response Entropy (GE Healthcare), and calculate the spectral edge frequency 95% (SEF95). Richmond Agitation-Sedation Scale (RASS) scores were assessed continually throughout the procedure and in recovery. We assessed the correlation between EEG markers and constructed ordinal logistic regression models to predict the RASS score and compare EEG markers. All three commercial EEG metrics were significantly associated with the RASS score (p < 0.001 for all metrics) whereas SEF95 alone was insufficient at characterizing dexmedetomidine sedation. PSI and Entropy achieved higher accuracy at predicing deeper levels of sedation as compared to BIS (PSI: 58.3%, Entropy: 58.3%, BIS: 44.4%). Lightening secondary to RASS score assessment is significantly captured by all three commercial EEG metrics (p < 0.001). Commercial EEG monitors can capture changes in the brain state associated with the RASS score during dexmedetomidine sedation. PSI and Entropy were highly correlated and may be better suited for assessing deeper levels of sedation.

Comparison Effects of Propofol-Dexmedetomidine versus Propofol-Remifentanil for Endoscopic Ultrasonography: A Prospective Randomized Comparative Trial

Objective. To compare the effects of propofol-dexmedetomidine versus propofol-remifentanil for endoscopic ultrasonography (EUS). Design, Setting, and Participants. A single-center, randomized trial from August 20, 2020 to August 20, 2021, in patients undergoing EUS. Interventions. Propofol-dexmedetomidine (PD) versus propofol-remifentanil (PR). Outcome Measures. The primary outcome was the endoscopist satisfaction level. The secondary outcomes included patient satisfaction, the incidence of adverse events, induction time, and time to achieve postanesthesia discharge score (PADS) ≥9. Methods. Total of 200 patients were enrolled and randomized into PD and PR groups. A bolus dose of 0.5 μg/kg dexmedetomidine was injected intravenously for 5 min. Subsequently, a continuous infusion of 0.5 μg/kg/h for the PD group. Remifentanil was continuously infused at 1.5 μg/kg/h for the PR group. A bolus dose of 1 mg/kg propofol was administered to both groups and then continuously infused. Results. The endoscopist satisfaction level was higher in the PR group than in the PD group ( $P=0.009$ ). Patient satisfaction was not significantly different between the groups ( $P=0.738$ ). No patients required mask ventilation or tracheal intubation in both groups. All patients were relatively hemodynamically stable. The incidence of body movements during the procedure in the PD group was higher than in the PR group ( $P=0.035$ ). The induction time and time taken to achieve PADS ≥9 in the PD group were longer than in the PR group ( $P<0.05$ ). Conclusions. PR sedation can increase the satisfaction level of the endoscopist by providing faster induction time and lower body movement and that of the patient by achieving faster PADS than PD sedation. Trial registration number: http://www.chictr.org.cn (ChiCTR2000034987).

Midazolam versus Dexmedetomidine in Patients at Risk of Obstructive Sleep Apnea during Urology Procedures: A Randomized Controlled Trial

Benzodiazepines are the most commonly used sedatives for the reduction of patient anxiety. However, they have adverse intraoperative effects, especially in obstructive sleep apnea (OSA) patients. This study aimed to compare dexmedetomidine (DEX) and midazolam (MDZ) sedation considering intraoperative complications during transurethral resections of the bladder and prostate regarding the risk for OSA. This study was a blinded randomized clinical trial, which included 115 adult patients with a mean age of 65 undergoing urological procedures. Patients were divided into four groups regarding OSA risk (low to medium and high) and choice of either MDZ or DEX. The doses were titrated to reach a Ramsay sedation scale score of 4/5. The intraoperative complications were recorded. Incidence rates of desaturations (44% vs. 12.7%, p = 0.0001), snoring (76% vs. 49%, p = 0.0008), restlessness (26.7% vs. 1.8%, p = 0.0044), and coughing (42.1% vs. 14.5%, p = 0.0001) were higher in the MDZ group compared with DEX, independently of OSA risk. Having a high risk for OSA increased the incidence rates of desaturation (51.2% vs. 15.7%, p < 0.0001) and snoring (90% vs. 47.1%, p < 0.0001), regardless of the sedative choice. DEX produced fewer intraoperative complications over MDZ during sedation in both low to medium risk and high-risk OSA patients.

Sedation-analgesia techniques for nonoperating room anesthesia: an update

PURPOSE OF REVIEW

There has been a substantial increase in nonoperating room anesthesia procedures over the years along with an increase in the complexity and severity of cases. These procedures pose unique challenges for anesthesia providers requiring meticulous planning and attention to detail. Advancements in the delivery of sedation and analgesia in this setting will help anesthesia providers navigate these challenges and improve patient safety and outcomes.

RECENT FINDINGS

There has been a renewed interest in the development of newer sedative and analgesic drugs and delivery systems that can safely provide anesthesia care in challenging situations and circumstances.

SUMMARY

Delivery of anesthesia care in nonoperating room locations is associated with significant challenges. The advent of sedative and analgesic drugs that can be safely used in situations where monitoring capabilities are limited in conjunction with delivery systems, that can incorporate unique patient characteristics and ensure the safe delivery of these drugs, has the potential to improve patient safety and outcomes. Further research is needed in these areas to develop newer drugs and delivery systems.

Anesthetic Management of a Patient With Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited arrhythmogenic disorder induced by adrenergic stress. Electrophysiologically, it is characterized by emotional stress- or exercise-induced bidirectional ventricular tachycardia that may result in cardiac arrest. Minimizing perioperative stress is critical as it can reduce fatal arrhythmias in patients with CPVT. Dexmedetomidine (DEX), a centrally acting sympatholytic anesthetic agent, was used in the successful intravenous (IV) moderate sedation of a 27-year-old female patient with CPVT, a history of cardiac events, and significant dental fear and anxiety scheduled to undergo mandibular left third molar extraction. Oral surgery was successfully performed under DEX-based IV sedation to reduce stress, and no arrhythmias were observed. IV sedation with DEX provided a sympatholytic effect with respiratory and cardiovascular stability in this patient with CPVT who underwent oral surgery.

Effectiveness of single loading dose of dexmedetomidine combined with propofol for deep sedation of endoscopic retrograde cholangiopancreatography (ERCP) in elderly patients: a prospective randomized study

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is an advanced endoscopic procedure and requires deep sedation. Deep sedation with dexmedetomidine for the respiratory drive preserved has become popular in recent years. However, the use of dexmedetomidine in elderly patients is controversial because its adverse events are more common. The objective of this study was to investigate the effectiveness of a single loading dose of dexmedetomidine combined with propofol for deep sedation of ERCP in elderly patients.

Methods

In this prospective randomized trial, 49 elderly patients undergoing ERCP were randomly allocated to the dexmedetomidine (DEX) or propofol (PRO) groups. The single loading dose of dexmedetomidine was set at 0.5 μg/kg at the start of anesthesia induction and loading for 10 min. The primary outcome was the cumulative dose of propofol. Secondary outcomes included time to awake, the frequency of airway interventions, and hemodynamics.

Results

The intraoperative cumulative dose of propofol was lower in the DEX group (111.0 ± 12.6 μg/kg/min) than the PRO group (143.7 ± 23.4 μg/kg/min) (P < 0.001). There was no statistically significant difference in the time to awake between the two groups. The incidence of artificial airway interventions and hypotension in the PRO group (36%, 60%) were significantly higher than those in the DEX group (4.2%, 16.7%) (P = 0.011, P = 0.003, respectively). In addition, the occurrence of bradycardia increased significantly in the DEX group (58.3%) compared with the PRO group (12%) (P < 0.001).

Conclusions

The single loading dose of dexmedetomidine combined with propofol can reduce propofol consumption and artificial airway intervention and provide better hemodynamic stability than propofol for deep sedation in elderly patients during ERCP.

Trial registration

www.chictr.org.cn (Registration number ChiCTR1900028069, Registration date 10/12/2019).

Intravenous Dexmedetomidine as an Adjunct to Neuraxial Anesthesia in Cesarean Delivery: A Retrospective Chart Review

Background

Dexmedetomidine is a selective α-2 agonist commonly used for sedation that has been used in obstetric anesthesia for multimodal labor analgesia, postcesarean delivery analgesia, and perioperative shivering. This study evaluated the role of intravenous dexmedetomidine to provide rescue analgesia and/or sedation during cesarean delivery under neuraxial anesthesia.

Methods

We conducted a single-center, retrospective cohort study of all parturients undergoing cesarean delivery under neuraxial anesthesia between December 1, 2018, and November 30, 2019, who required supplemental analgesia during the procedure. Patients were divided into two groups: patients who received intravenous dexmedetomidine (Dexmed group) and patients who received adjunct medications such as fentanyl, midazolam, ketamine, and nitrous oxide (Standard group). Primary outcome was incidence of conversion to general anesthesia.

Results

During the study period, 107 patients received adjunct medications. There was no difference in conversion to general anesthesia between the Dexmed group and the Standard group (6% (4/62) vs. 9% (4/45); p=0.718). In the Dexmed group, the mean dexmedetomidine dose received was 37 μg (range 10 to 140 μg). While the use of inotropic/vasopressor medications was common and similar in both groups, there was an increase in the incidence of bradycardia (Dexmed 15% vs. Standard 2%; p=0.042) but not hypotension (Dexmed 24% vs. Standard 24%; p=1.00) in the Dexmed group.

Conclusion

In patients who required supplemental analgesia for cesarean delivery, those who received dexmedetomidine versus other medications had a similar rate of conversion to general anesthesia, a statistically significant increase in bradycardia, but no difference in the incidence of hypotension.

General anesthetic techniques for enhanced recovery after surgery: Current controversies

General anesthesia technique can influence not only immediate postoperative outcomes, but also long-term outcomes beyond hospital stay (e.g., readmission after discharge from hospital). There is lack of evidence regarding superiority of total intravenous anesthesia over inhalation anesthesia with regards to postoperative outcomes even in high-risk population including cancer patients. Optimal balanced general anesthetic technique for enhance recovery after elective surgery in adults includes avoidance of routine use preoperative midazolam, avoidance of deep anesthesia, use of opioid-sparing approach, and minimization of neuromuscular blocking agents and appropriate reversal of residual paralysis. Given that the residual effects of drugs used during anesthesia can increase postoperative morbidity and delay recovery, it is prudent to use a minimal number of drug combinations, and the drugs used are shorter-acting and administered at the lowest possible dose. It is imperative that the discerning anesthesiologist consider whether each drug used is really necessary for accomplishing perioperative goals.

Effectiveness and safety of intravenous dexmedetomidine sedation for ophthalmic surgery under regional anesthesia

PURPOSE

To assess the effectiveness and safety of intravenous (IV) dexmedetomidine for sedation in ophthalmic surgery.

METHODS

Prospective, observational, uncontrolled, single-center study. Patients were sedated with a continuous dexmedetomidine IV infusion started 15 min before regional anesthesia administration and maintained up to the end of surgery. Effectiveness of dexmedetomidine was assessed by the Modified Observer's Assessment of Alertness and Sedation (MOAA/S) targeted at 5. Safety was assessed by the incidence of patients' movements/snoring and by the incidence of respiratory and haemodynamic complications. An eleven-point numerical rating scale (NRS) was used to assess the level of satisfaction of both the surgeon and the patient.

RESULTS

123 patients (73 males, mean age: 63 ± 13) were included; 81 (81/123; 65.8%) patients reached the requested MOAA/S score of 5. Any intraoperative movement - mostly voluntary - occurred in 34 (34/123; 27.6%) cases with no need for a switch to general anaesthesia; no ocular complications related to the intraoperative movements occurred. Intraoperative snoring occurred in 30 (30/123; 24.4%) patients and it did not affect the surgical manoeuvres. Respiratory drive depression requiring manual or mechanical ventilation never occurred. Bradycardia occurred in 14 (14/123; 11.3%), cases but only 4 (4/123; 3.2%) patients required atropine administration, which was always effective. Intraoperative analgesia was consistently obtained and both the surgeons and the patients reported a high NRS satisfaction score.

CONCLUSION

Dexmedetomidine provided adequate sedation in patients undergoing ocular surgery under local anaesthesia and showed a good effectiveness and safety profile. Upper airway obstruction, apnoea and snoring can occur.

Intraoperative Dexmedetomidine and Ketamine Infusions in an Enhanced Recovery After Thoracic Surgery Program: A Propensity Score Matched Analysis

OBJECTIVES

To assess the impact of intraoperative dexmedetomidine and ketamine on postoperative pain and opioid consumption within an ERAS program in thoracic pulmonary oncologic surgery.

DESIGN

Retrospective, propensity-score matched analysis SETTING: Enhanced Recovery After Surgery (ERAS) program.

PARTICIPANTS

Patients undergoing thoracic pulmonary oncologic surgery between March 2016 and April 2020.

INTERVENTIONS

Continuous infusion of dexmedetomidine and ketamine.

MEASUREMENTS & MAIN RESULTS

The authors initially analyzed data of 1,630 patients undergoing thoracic pulmonary oncologic surgery within their ERAS program. In total, 117 matched pairs were included in this analysis. Patients in the intraoperative dexmedetomidine + ketamine group were more likely to be opioid-free (76.6% vs 60.9%, P<0.01). Raw analysis showed lower pain scores at PACU admission (2.8±2.0 vs 3.4±2.0, P=0.03) and less opioid consumption at PACU admission (5 MED [0-10] vs 7.5 MED [0-15], P=0.03) in the dexmedetomidine + ketamine group; however, these differences were not present after adjusting for multiplicity. There were no significant differences in the length of PACU stay (1.9 hours [1.5-2.8] vs 2.0 hours [1.4-2.9], P=0.48) or hospital stay (three days [two-five] vs three days [two-five], P=0.08). Both groups had similar rates of pulmonary complications (5.9% vs 9.4%, P=0.326), ileus (0.9% vs 0.9%, P=1.00), and 30-day readmission (2.6% vs 4.3%, P=0.722).

CONCLUSIONS

There were no differences in postoperative pain scores and opioid consumption throughout their hospital stay between patients receiving concomitant dexmedetomidine and ketamine infusions versus patients who did not receive these infusions during thoracic surgery.

Pharmacologically Induced Ventilatory Depression in the Postoperative Patient: A Sleep-Wake State-Dependent Perspective

Pharmacologically induced ventilatory depression (PIVD) is a common postoperative complication with a spectrum of severity ranging from mild hypoventilation to severe ventilatory depression, potentially leading to anoxic brain injury and death. Recent studies, using continuous monitoring technologies, have revealed alarming rates of previously undetected severe episodes of postoperative ventilatory depression, rendering the recognition of such episodes by the standard intermittent assessment practice, quite problematic. This imprecise description of the epidemiologic landscape of PIVD has thus stymied efforts to understand better its pathophysiology and quantify relevant risk factors for this postoperative complication. The residual effects of various perianesthetic agents on ventilatory control, as well as the multiple interactions of these drugs with patient-related factors and phenotypes, make postoperative recovery of ventilation after surgery and anesthesia a highly complex physiological event. The sleep-wake, state-dependent variation in the control of ventilation seems to play a central role in the mechanisms potentially enhancing the risk for PIVD. Herein, we discuss emerging evidence regarding the epidemiology, risk factors, and potential mechanisms of PIVD.

A decade later, there are still major issues to be addressed in paediatric anaesthesia

PURPOSE OF REVIEW

Despite real advances in paediatric anaesthesia management, such as a growing awareness of the relevance of anaesthesia conduct as well as of the lack of evidence for neurotoxicity of anaesthetic agents, it must be said that there are still important questions in our specialty that remain unanswered. Standardization and harmonization of airway management, analgesia techniques and outcome measures are the important issues we are facing at the beginning of this decade.

RECENT FINDINGS

Major improvements in airway management of neonates and infants resulted from the introduction of videolaryngoscopes and the systematic use of nasal oxygenation during endotracheal intubation. Similarly, the increasing popularity of dexmedetomidine has led to the generalization of its use, which, considering that it may produce undesirable effects, poses a challenge for the future. Moreover, recent systematic reviews have confirmed a lack of evidence for the efficacy of many techniques used in clinical practice.

SUMMARY

The shift in research from the neurotoxicity of anaesthetic agents to factors related to anaesthetic conduct are discussed. Examples for an improvement in anaesthesia management are highlighted with advocacy for including these evidence-based findings in routine clinical practice. Finally, the impact of using clinically relevant age-related and patient-centred perioperative outcomes is essential for comparing and/or interpreting the safety and efficacy of anaesthesia and analgesia management in children.

Perioperative Opioid Administration

Opioids form an important component of general anesthesia and perioperative analgesia. Discharge opioid prescriptions are identified as a contributor for persistent opioid use and diversion. In parallel, there is increased enthusiasm to advocate opioid-free strategies, which include a combination of known analgesics and adjuvants, many of which are in the form of continuous infusions. This article critically reviews perioperative opioid use, especially in view of opioid-sparing versus opioid-free strategies. The data indicate that opioid-free strategies, however noble in their cause, do not fully acknowledge the limitations and gaps within the existing evidence and clinical practice considerations. Moreover, they do not allow analgesic titration based on patient needs; are unclear about optimal components and their role in different surgical settings and perioperative phases; and do not serve to decrease the risk of persistent opioid use, thereby distracting us from optimizing pain and minimizing realistic long-term harms.

Feasibility of Intranasal Dexmedetomidine in Treatment of Postoperative Restlessness, Agitation, and Pain in Geriatric Orthopedic Patients

Objective

The aim of this study was to report preliminary data on the use of intranasal dexmedetomidine to treat postoperative restlessness, agitation, and pain in 23 patients aged > 70 years and undergoing orthopedic surgery.

Background

Postoperative agitation and delirium are common among older adult patients undergoing orthopedic surgery. Most preparations used to treat agitation and delirium carry a risk for adverse events such as respiratory failure. Moreover, mere opioid therapy may be insufficient in treatment of pain. Dexmedetomidine, an α2-adrenoreceptor agonist with sedative and analgesic properties, has been shown to reduce opioid requirement and reduce postoperative delirium in older adults.

Methods

We studied the use of post-operative intranasal dexmedetomidine in a retrospective study cohort of geriatric patients undergoing orthopedic surgery. Primary outcomes included alterations in heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral oxygen saturation (SpO2), Modified Richmond Agitation and Sedation Score (mRASS), and opioid consumption following dexmedetomidine administration.

Results

We identified 23 patients with a mean (SD) age of 79.9 (7.5) years who received dexmedetomidine 100 µg intranasally postoperatively. After dexmedetomidine administration, HR decreased by 10.4 (3.7) beats/min (95% CI 2.9–17.8; p = 0.004) and MAP by 16.2 (4.4) mmHg (95% CI 7.3–25.1; p < 0.001). HR decrease was significant at 2 h and MAP decrease at 1, 2, and 3 h following dexmedetomidine administration. Dexmedetomidine administration was associated with significant reductions in opioid consumption (p < 0.001) and mRASS score (p < 0.001). SpO₂ and RR remained unchanged.

Conclusions

These preliminary findings suggest that intranasal dexmedetomidine reduces opioid consumption without causing respiratory depression and may be used to treat postoperative restlessness, agitation, and pain in geriatric patients. However, hemodynamic effects of dexmedetomidine may require close observation for 3 hours following administration in older adult patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40266-021-00846-6.

Developing a minimally-invasive anaesthesiological approach to non-intubated uniportal video-assisted thoracoscopic surgery in minor and major thoracic surgery

Background

Non-intubated uniportal video-assisted thoracoscopic surgery (niVATS) is a novel approach to major and minor lung resection. It benefits from a holistic anesthesiological concept with adequate pain relief and sedation in a minimal-invasive setup allowing thoracic procedures under spontaneous breathing. At present no anesthesiological gold standard for niVATS exists. The primary aim of our retrospective observational study was to evaluate feasibility and safety of minimally invasive niVATS for both minor and major pulmonary resections at our institution.

Methods

All 88 consecutive patients scheduled for niVATS minor or major thoracic procedures were included into the study. Anaesthesia was performed according to a departmental niVATS algorithm including both regional anaesthesia and sedation. Patient characteristics and early outcome data including intraoperative and postoperative findings were compared between groups. Prediction scores for postoperative complications (LAS VEGAS, ARISCAT, ThRCRI) were calculated and compared.

Results

No early mortality and a low overall morbidity rate of 28.4% were encountered. Conversion to orotracheal intubation was required in 6.8% of all cases. Postoperative pulmonary complications occurred in 15.9% of total cases and were lower than predicted by both LAS VEGAS and ARISCAT respectively. Cardiac complications were found in 1.1% and lower than predicted by ThRCRI. A persistent air leak occurred in 11.4% of total cases and was significantly higher in major resection. Postoperative chest tube duration and hospital length of stay in the major resection group exceeded times reported by other groups.

Conclusions

niVATS appears to be safe in both minor and major thoracic procedures. A minimally invasive anaesthesiological approach foregoing central iv lines, arterial blood pressure measurement and urinary catheterization is feasible. Our niVATS protocol appears to be a viable alternative for both minor and major thoracic procedures in selected patients.

Enhanced recovery pathways for ambulatory surgery

PURPOSE OF REVIEW

Implementation of enhanced recovery pathways have allowed migration of complex surgical procedures from inpatient setting to the outpatient setting. These programs improve patient safety and patient-reported outcomes. The present article discusses the principles of enhanced recovery pathways in adults undergoing ambulatory surgery with an aim of improving patient safety and postoperative outcomes.

RECENT FINDINGS

Procedure and patient selection is one of the key elements that influences perioperative outcomes after ambulatory surgery. Other elements include optimization of comorbid conditions, patient and family education, minimal preoperative fasting and adequate hydration during the fasting period, use of fast-track anesthesia technique, lung-protective mechanical ventilation, maintenance of fluid balance, and multimodal pain, nausea, and vomiting prophylaxis.

SUMMARY

Implementation of enhanced recovery pathways requires a multidisciplinary approach in which the anesthesiologist should take a lead in collaborating with surgeons and perioperative nurses. Measuring compliance with enhanced recovery pathways through an audit program is essential to evaluate success and need for protocol modification. The metrics to assess the impact of enhanced recovery pathways include complication rates, patient reported outcomes, duration of postoperative stay in the surgical facility, unplanned hospital admission rate, and 7-day and 30-day readmission rates.

Comparing two airway management strategies for moderately sedated patients undergoing awake craniotomy: A single-blinded randomized controlled trial

BACKGROUND

In the monitored anesthesia care (MAC) setting for awake craniotomy (AC), maintaining airway patency in sedated patients remains challenging. This randomized controlled trial aimed to compare the validity of the below-epiglottis transnasal tube insertion (the tip of the tube placed between the epiglottis and vocal cords) and the nasopharyngeal airway (simulated by the above-epiglottis transnasal tube with the tip of the tube placed between the epiglottis and the free edge of the soft palate) with respect to maintaining upper airway patency for moderately sedated patients undergoing AC.

METHODS

Sixty patients scheduled for elective AC were randomized to receive below-epiglottis (n = 30) or above-epiglottis (n = 30) transnasal tube insertion before surgery. Moderate sedation was maintained in the pre- and post-awake phases. The primary outcome was the upper airway obstruction (UAO) remission rate (relieved obstructions after tube insertion/the total number of obstructions before tube insertion).

RESULTS

The UAO remission rate was higher in the below-epiglottis group [100% (12/12) vs 45% (5/11); P = .005]. The tidal volume values monitored through the tube were greater in the below-epiglottis group during the pre-awake phase (P < .001). End-tidal carbon dioxide (EtCO₂ ) monitored through the tube was higher in the below-epiglottis group at bone flap removal (P < .001). During the awake phase, patients' ability to speak was not impeded. No patient had serious complications related to the tube.

CONCLUSION

The below-epiglottis tube insertion is a more effective method to maintain upper airway patency than the nasopharyngeal airway for moderately sedated patients undergoing AC.

Upper-airway collapsibility and compensatory responses under moderate sedation with ketamine, dexmedetomidine, and propofol in healthy volunteers

BACKGROUND

Ketamine is a potent sedative drug that helps to maintain upper-airway patency, due to its higher upper-airway dilator muscular activity and higher level of duty cycle, as seen in rats. However, no clinical trials have tested passive upper-airway collapsibility and changes in the inspiratory duty cycle against partial upper-airway obstruction in humans. The present study evaluated both the passive mechanical upper-airway collapsibility and compensatory response against acute partial upper-airway obstruction using three different sedative drugs in a crossover trial.

METHODS

Eight male volunteers entered this nonblinded, randomized crossover study. Upper-airway collapsibility (passive critical closing pressure) and inspiratory duty cycle were measured under moderate sedation with ketamine, propofol, and dexmedetomidine. Propofol, dexmedetomidine, and ketamine anesthesia were induced to obtain adequate, same-level sedation, with a BIS value of 50-70 and the OAA/S score of 2-3 and RASS score of -3.

RESULTS

The median passive critical closing pressure of 0.08 [-5.51 to 1.20] cm H2 O was not significantly different compared to that of propofol sedation (-0.32 [-1.41 to -0.19] cm H2 O) and of dexmedetomidine sedation (-0.28 [-0.95 to -0.03] cm H2 O) (p = .045). The median passive RUS for ketamine 54.35 [32.00 to 117.50] cm H2 O/L/s was significantly higher than that for propofol 5.50 [2.475 to 19.60] cm H2 O/L/s; (mean difference, 27.50; 95% CI 9.17 to 45.83) (p = .009) and for dexmedetomidine 19.25 [4.125 to 22.05] cm H2 O/L/s; (mean difference, 22.88; 95% CI 4.67 to 41.09) (p = .021). The inspiratory duty cycle increased significantly as the inspiratory airflow decreased in passive conditions for each sedative drug, but behavior differed among the three sedative drugs.

CONCLUSION

Our findings demonstrate that ketamine sedation may have an advantage of both maintained passive upper-airway collapsibility and a compensatory respiratory response, due to both increase in neuromuscular activity and the increased duty cycle, to acute partial upper-airway obstruction.

Tracheal extubation in children: Planning, technique, and complications

Although poorly described in textbooks and rarely a topic of lecture, tracheal extubation is a critical phase of anesthetic care. It should therefore be carefully planned taking into account simple physiology-based principles to maintain the upper airway patent and avoid lung de-recruitment, but also the pharmacology of all anesthetic agents used. Although the management of most of its complications can be learned in a clinical simulation environment, the basic techniques can so far only be taught at the bedside, in the operating room. In this paper, the process of extubation is described in successive steps: preparation, return to adequate spontaneous ventilation, awake versus deep extubation, timing according to the child's breathing cycle, extubation in the operating room or in the Postanesthesia Care unit, child's management immediately after extubation, diagnosis and treatment of the early complications, and finally, how to prepare for a difficult reintubation.