Intranasal Dexmedetomidine Sedation as Adjuvant Therapy in Acute Asthma Exacerbation With Marked Anxiety and Agitation

The use of dexmedetomidine in the emergency department: A systematic review

BACKGROUND

Dexmedetomidine (DEX), a centrally acting alpha-2 agonist, is increasingly used for sedation in multiple clinical settings. Evidence from the intensive care unit and operative settings suggests DEX may have significant advantages over traditional GABAergic sedatives such as benzodiazepines. There has been limited research on the use of DEX in the emergency department (ED).

METHODS

We performed a systematic review of the medical literature to identify all published evidence regarding the use of DEX in the ED. We included randomized and nonrandomized studies and studies reporting any use of DEX in the ED, even when it was not the primary focus of the study. Two authors reviewed studies for inclusion, and a single author assessed studies for quality and risk of bias and abstracted data.

RESULTS

We identified 35 studies meeting inclusion criteria, including 11 randomized controlled trials, 13 cohort and other nonrandomized studies, and 11 case reports and case series. Significant heterogeneity in interventions, comparators, indications, and outcomes precluded data pooling and meta-analysis. We found modest evidence that DEX was efficacious in facilitating medical imaging and mixed and limited evidence regarding its efficacy for procedural sedation and sedation of nonintubated medical and psychiatric patients. Our results suggested that DEX is associated with bradycardia and hypotension, which are generally transient and infrequently require medical intervention.

CONCLUSIONS

A limited body of generally poor- to moderate-quality evidence suggests that the use of DEX may be efficacious in certain clinical scenarios in the ED and that DEX use in the ED is likely safe. Further high-quality research into DEX use in the ED setting is needed, with a particular focus on clear and consistent selection of indications, identification of clear and clinically relevant primary outcomes, and careful assessment of the clinical implications of the hemodynamic effects of DEX therapy.

Dexmedetomidine as an adjunctive treatment for acute asthma

Objective

This study aimed to compare the efficacy of using dexmedetomidine with salbutamol and salbutamol nebulization alone in patients with acute exacerbation of asthma presenting to the emergency department.

Methods

This clinical trial included 60 patients, in the age range of 18 to 55 years, with signs of bronchospasm presenting to the emergency department. In the intervention group, dexmedetomidine 0.5 µg/kg was injected intravenously and three doses of salbutamol nebulization were administered over 60 minutes. In the control group, salbutamol nebulization was administered for 60 minutes three times. The patient’s clinical status, based on clinical symptoms, consciousness, speech, breathing rate, heart rate, and blood pressure were recorded before the intervention, and peak expiratory flow rate and forced expiratory volume in 1 second were measured at 20, 40, and 60 minutes after intervention. Patients who did not respond to the intervention were excluded from the study within 60 minutes.

Results

The increased mean forced expiratory volume in 1 second and mean peak expiratory flow rate were found to be similar in both groups during the treatment (P=0.304). The mean systolic and diastolic blood pressure recorded at 40 and 60 minutes were significantly lower in the intervention group. During this study, no patient was excluded before 60 minutes.

Conclusion

Administration of dexmedetomidine in addition to standard salbutamol treatment has no beneficial effect in patients with acute asthma attacks and merely causes hypotension in patients.

Sevoflurane modulates AQPs (1,5) expression and endoplasmic reticulum stress in mice lung with allergic airway inflammation

Sevoflurane was found to show protective roles in mice with asthma, however, the mechanism of which needs further exploring. Aquaporins (AQPs) have been demonstrated to be involved in the pathogenesis of asthma, while endoplasmic reticulum stress has been reported to be related to many inflammatory diseases and involved in protein processing, including AQPs. The present study aimed to determine the role of sevoflurane in AQPs (AQP1,3,4,5) expression in mice with allergic airway inflammation and the probable mechanism. The increased number of inflammatory cells infiltrating the lung tissue, and the elevated levels of tumor necrosis factor-α (TNF-α) and interleukin (IL) 13 (IL-13) were all decreased after sevoflurane treatment (all P<0.05). Meanwhile, mRNA levels of AQP1 and AQP5 but not AQP3 and AQP4 were decreased in ovalbumin (OVA)-induced allergic mice lung. Both the decreased mRNA expression and protein levels of AQP1 and AQP5 in allergic lung tissues were reversed by sevoflurane treatment. Furthermore, we established that sevoflurane inhibited the OVA-induced protein increase in the endoplasmic reticulum (ER) stress markers BiP and C/EBP homologous protein (CHOP). Collectively, these findings suggested that sevoflurane modulated the expression and protein level of AOPs (AQP1, AQP5) as well as inhibited ER stress response in OVA-induced allergic airway inflammation of mice.