Delayed Extubation of a Patient With Multiple Sclerosis

The potential complications associated with gastroparesis in the perioperative setting for patients with multiple sclerosis (MS) are inadequately recognized. While gastroparesis is commonly associated with diabetes mellitus-induced neuropathy and postsurgical complications, its prevalence and impact on patients with MS are less understood. This is particularly crucial as the systemic autoimmune nature of MS may extend its neurological effects to the gastrointestinal (GI) tract. In this context, we present a case wherein undiagnosed gastroparesis significantly contributed to postoperative challenges, leading to delayed extubation in a patient with MS. This underscores the importance of considering gastroparesis as a potential differential diagnosis and developing a comprehensive approach to evaluating and managing MS patients, which may help mitigate perioperative complications and inform tailored anesthetic management strategies.

Delayed awakening and its associated factor following general anesthesia service, 2022: a cross-sectional study

Background

The time to emerge from anesthesia is affected by patient factors, anesthetic factors, the duration of surgery, and preoperative and intraoperative pain management.

Objective

This study aimed to determine the prevalence and contributing factors of delayed awakening following general anesthesia.

Method

A cross-sectional study was conducted from January to June 2022. After getting ethical approval with the permission number S/C/R 37/01/2022, willing patients participate with written informed consent. Chart reviews in the preoperative and postoperative recovery rooms were used to collect data. Frequency and percentage with cross-tabulation were used to provide the descriptive statistics. To determine the predictive variables that were associated with the outcome variable, bivariable, and multivariable logistic regression models were fitted. The statistical significance was evaluated using P-values of 0.05 for multivariable regression.

Results

In the current study, a normal emergency occurred in 91.7% of surgical patients receiving general anesthesia, while delayed awakening, emergence with hypoactive, and emergence with delirium occurred in 2.6, 3.9, and 1.8% of cases, respectively. Patients older than 64 years [adjusted odds ratio (AOR): 1.33, 95% CI: 0.83-7.191], being diploma anesthesia providers (AOR: 2.38, 95% CI: 2.05-7.15), opioids (AOR: 2.3, 95% CI: 2.20-5.76), surgery lasting longer than 2 h (AOR: 1.91, 95% CI: 1.83-6.14), estimated blood loss of more than 1500 ml (AOR: 1.20, 95% CI: 0.62-11.30), crystalloid administration of more than 3000 ml (AOR: 3.12, 95% CI: 2.19-7.32), intraoperative hypotension (AOR: 3.37, 95% CI: 2.93-9.41) and extreme body weight, were significantly linked to delayed awakening after general anesthesia.

Conclusion

Although delayed emergence is an uncommon condition with a number of contributing causes, it is preventable, and once it has occurred, it presents a challenge for anesthetists.

Dopamine D1 receptor in the NAc shell is involved in delayed emergence from isoflurane anesthesia in aged mice

BACKGROUND

Delayed emergence after general anesthesia tends to occur in the elderly population, but the mechanism remains unclear. Apart from age-related pharmacokinetic changes, the aging-induced structural and functional alterations in the arousal-promoting neural substrates should be considered. The nucleus accumbens (NAc) is a crucial arousal-related nucleus, in which activating medium spiny neurons (MSNs) expressing dopamine D1 receptor (D1R) could facilitate the arousal from natural sleep. Meanwhile, the dopaminergic systems decline with aging in multiple brain regions. However, whether the age-related decline in D1R in the NAc shell attenuates its arousal-promoting capacity from general anesthesia remains to be elucidated.

METHODS

We first verified the delayed emergence from isoflurane anesthesia and examined the corresponding changes of electroencephalogram (EEG) power in aged mice. In turn, the arousal-modulating capacity of D1R was characterized in the young and aged cohorts by microinjection of D1R agonist/antagonist into the NAc shell. Furthermore, to address the possible mechanism responsible for the attenuated arousal-modulating capacity of the aged NAc, the expression of D1R in the NAc shell was measured and compared between young and aged mice.

RESULTS

Our data indicated that compared with young mice, the emergence time in aged mice was notably longer, while EEG power in δ band (1-4Hz) was significantly higher and power in β band (12-25Hz) was lower. Activating or inhibiting D1R in the NAc shell by microinjection D1R agonist/antagonist promoted or delayed the emergence process in young mice. Nevertheless, this modulation capacity of D1R in the NAc shell declined in aged mice, respectively. Meanwhile, downregulation of D1R expression in the NAc shell was detected in the aged brain.

CONCLUSION

Together, these results suggest that aging attenuates the arousal-modulating capacity of D1R in the NAc shell probably through downregulation of D1R expression therein, which may provide a potential explanation and a therapeutic target for increased sensitivity to anesthetics in the elderly patients.

Delayed Emergence from Anesthesia: What We Know and How We Act

The emergence from anesthesia is the stage of general anesthesia featuring the patient’s progression from the unconsciousness status to wakefulness and restoration of consciousness. This complex process has precise neurobiology which differs from that of induction. Despite the medications commonly used in anesthesia allow recovery in a few minutes, a delay in waking up from anesthesia, called delayed emergence, may occur. This phenomenon is associated with delays in the operating room, and an overall increase in costs. Together with the emergence delirium, the phenomenon represents a manifestation of inadequate emergence. Nevertheless, in delayed emergence, the transition from unconsciousness to complete wakefulness usually occurs along a normal trajectory, although slowed down. On the other hand, this awakening trajectory could proceed abnormally, possibly culminating in the manifestation of emergence delirium. Clinically, delayed emergence often represents a challenge for clinicians who must make an accurate diagnosis of the underlying cause to quickly establish appropriate therapy. This paper aimed at presenting an update on the phenomenon, analyzing its causes. Diagnostic and therapeutic strategies are addressed. Finally, therapeutic perspectives on the “active awakening” are reported.

Calabadion 1 selectively reverses respiratory and central nervous system effects of fentanyl in a rat model

BACKGROUND

We hypothesised that Calabadion 1, an acyclic cucurbit[n]uril molecular container, reverses fentanyl-induced respiratory depression and dysfunction of the CNS.

METHODS

Experiments were conducted in male Sprague-Dawley rats. A constant-rate i.v. infusion of fentanyl (12.5 or 25 μg kg^-1 over 15 min) was administered followed by an i.v. bolus of Calabadion 1 (0.5-200 mg kg^-1) or placebo. The primary outcome was reversal of ventilatory and respiratory depression, assessed by pneumotachography and arterial blood gas analysis, respectively. Key secondary outcomes were effects on fentanyl-induced central nervous dysfunction quantified by righting reflex, balance beam test, and electromyography (EMG).

RESULTS

Calabadion 1 reversed fentanyl-induced respiratory depression across the endpoints minute ventilation, pH, and Paco₂ (P=0.001). Compared with placebo, Calabadion 1 dose dependently (P for trend <0.001) reversed fentanyl-induced hypoventilation {81.9 [5.1] (mean [standard error of the mean]) vs 45.5 [12.4] ml min^-1; P<0.001}, acidosis (pH 7.43 [0.01] vs 7.28 [0.04]; P=0.005), and hypercarbia (Paco₂ 43.4 [1.6] vs 63.4 [8.1] mm Hg; P=0.018). The effective Calabadion 1 doses required to reverse respiratory depression by 50% and 90% (ED50_Res and ED90_Res) were 1.7 and 15.6 mg kg^-1, respectively. Higher effective doses were needed for recovery of righting reflex (ED50_CNS: 9.6 mg kg^-1; ED90_CNS: 86.1 mg kg^-1), which was accelerated by Calabadion 1 (4.6 [0.3] vs 9.0 [0.7] min; P<0.001). Calabadion 1 also significantly accelerated recovery of full functional mobility and reversal of muscle rigidity.

CONCLUSIONS

Calabadion 1 selectively and dose dependently reversed the respiratory system and CNS side-effects of fentanyl.

Intellectual disability is a risk factor for delayed emergence from total intravenous anaesthesia

BACKGROUND

Previous studies have suggested that ID influences the depth of general anaesthesia (GA) and delays emergence from GA. In this retrospective cohort study, we investigated whether ID affects the time taken to emerge from GA.

METHODS

We selected dental patients who underwent GA at the Department of Dental Anaesthesiology, Okayama University Hospital, using predefined inclusion and exclusion criteria, before dividing the selected participants into ID and non-ID (control) groups. Relevant data were collected from electronic anaesthesia records. Emergence time, the time from the discontinuation of propofol and remifentanil to tracheal extubation, was recorded for each patient. We compared the data of the ID group and control group. The association between ID and the emergence time was tested for statistical significance. Multivariate linear regression analysis was used to control for confounders.

RESULTS

A total of 97 cases (control = 50, ID = 47) were included in the study. The emergence time was significantly longer in the ID group (ID group: 15.8 ± 6.6 min, control group: 10.8 ± 3.6 min). The ID group included more men and lower propofol and remifentanil infusion rates. The treatment time was longer, and the mean bispectral index was lower in the ID group. Sevoflurane inhalation was used only for anaesthesia induction in the ID group. In the multivariate linear regression analysis, ID was found to be significantly associated with a longer emergence time.

CONCLUSION

Our results suggest that ID is associated with a longer emergence time from GA.

Delayed recovery from anesthesia: A postgraduate educational review

Delayed awakening from anesthesia remains one of the biggest challenges that involve an anesthesiologist. With the general use of fast-acting anesthetic agents, patients usually awaken quickly in the postoperative period. The time to emerge from anesthesia is affected by patient factors, anesthetic factors, duration of surgery, and painful stimulation. The principal factors responsible for delayed awakening following anesthesia are anesthetic agents and medications used in the perioperative period. Nonpharmacological causes may have a serious sequel, hence recognizing these organic conditions is important. Certain underlying metabolic disorders such as hypoglycemia, severe hyperglycemia, and electrolyte imbalance, especially hypernatremia, hypoxia, hypercapnia, central anticholinergic syndrome, chronic hypertension, liver disease, hypoalbuminemia, uremia, and severe hypothyroidism may also be responsible for delayed recovery following anesthesia. Unexpected delayed emergence after general anesthesia may also be due to intraoperative cerebral hypoxia, hemorrhage, embolism, or thrombosis. Accurate diagnosis of the underlying cause is the key for the institution of appropriate therapy, but primary management is to maintain airway, breathing, and circulation. This comprehensive review discusses the risk factors, causes, evaluation and management of delayed recovery based on our clinical experience, and literature search on the internet, supported by the standard textbooks of anesthesiology.

Respiratory depression during VP shunting in Arnold Chiari malformation Type-II, a rare complication (Case reports and review of literature)

The VP Shunt is a common pediatric surgical procedure in our country. Hydrocephalus is commonly associated with meningomyelocele in Arnold Chiari malformation-II and the ventriculoperitoneal shunt insertion is the common surgical procedure for the management of hydrocephalus. The standard protocol is to rule out any hydrocephalus by preoperative MRI. If associated with hydrocephalus, insertion of the VP shunt is indicated before the repair of MMC whereas the absence of hydrocephalus indicates that the surgical repair of MMC is to be undertaken immediately. Anesthetic management of the patient during the insertion of ventriculoperitoneal shunt may pose problems. We report here two cases of ACM-II (lumbar MMC with associated hydrocephalus) who had respiratory depression / delayed emergence after an otherwise uneventful procedure. Although the VP shunt (first procedure) required postoperative ventilation which improved later, the phenomena of respiratory depression / delayed emergence did not occur after the MMC repair (second surgery). The possible mechanisms involved in these events and their various clinical aspects are discussed below.

Gender rather than choice of intermediate duration opioids affects emergence after craniotomy for large intracranial tumors

BACKGROUND

Opioid-based anesthetic techniques are commonly used during neurosurgical procedures. In the present randomized prospective study, we studied emergence after 4 anesthetic regimens combining intermediate duration opioids with isoflurane and nitrous oxide (N(2)O), in patients undergoing craniotomy for large (> 30 mm diameter with intracranial mass effect) intracranial tumors.

METHODS

One hundred seven patients were randomized into 4 groups: Group A: fentanyl (≤ 5 µg/kg) + isoflurane (≤ 1 minimum alveolar concentration [MAC]), Group B: sufentanil (1-2 µg/kg plus infusion) + isoflurane (≤ 0.5 MAC), Group C: sufentanil (2 µg/kg bolus only) + isoflurane (≤ 1 MAC), and Group D: alfentanil (100 µg/kg plus infusion) + isoflurane (≤ 0.5 MAC). Boluses were administered as divided doses during induction, laryngoscopy, head pinning, and incision. Blood pressure was controlled at ±25% of baseline levels. All infusions were discontinued at the start of dural closure. Emergence was assessed using a mini-neurologic examination consisting of 7 questions. Groups were compared on time to emergence using survival analysis methods.

RESULTS

The groups did not differ regarding extubation time, which occurred at a median of 4 to 6 minutes across groups after discontinuing N(2)O. The median emergence time ranged from 15 to 22.5 minutes and did not differ among groups. However, across all groups more women had emerged by 30 minutes compared with men (83% vs 57%, P  =  .002). The median emergence time in women was found to be significantly shorter (0-15 minutes) than in men (15-30 minutes) (P  =  .012).

CONCLUSIONS

No between-group differences in emergence time were observed; the study was stopped early because of evidence that no differences were likely to be found if the study were continued. However, in a post hoc analysis, female gender was associated with faster emergence.

Short delay in timing of emergence determines establishment success in Pinus sylvestris across microhabitats

BACKGROUND AND AIMS

The date of emergence may have far-reaching implications for seedling performance. Seedlings emerging early in the growing season often have a greater rate of survival or grow better if early emergence provides advantages with respect to an environmental cue. As a result, the benefits of early emergence may be lost if the environmental stress creating the differences among cohorts disappears. The experimental manipulation under field conditions of the factors that constitute the main sources of stress for seedling establishment is thus a straightforward method to evaluate the impact of date of emergence on seedling establishment under realistic conditions.

METHODS

Two field experiments were performed to analyse the effect of emergence date on survival and first-year growth of Scots pine seedlings in natural mountain forests in south-east Spain. Two main environmental factors that determine seedling success in these mountains were considered: (1) microhabitat type (monitoring the effect of date of emergence in the three most common microhabitats where seedlings recruit); (2) summer drought (monitored by an irrigation treatment with control and watered sampling points).

KEY RESULTS

Overall, early emergence resulted in a higher probability of survival and better growth in the two experiments and across microhabitats. However, the reduction in summer drought did not diminish the differences observed among cohorts: all cohorts increased their survival and growth, but early cohorts still had a clear advantage.

CONCLUSIONS

Date of emergence determines establishment success of Pinus sylvestris seedlings, even if cohorts are separated by only a few days, irrespective of the intensity of summer drought. The experimental design, covering a gradient of light intensity and soil moisture that simulates conditions of the regeneration niche of Scots pine across its geographical range, allows the results to be extrapolated to other areas of the species. Date of emergence is thus likely to have a large impact on the demography of Scots pine across its geographical range.