Comparing the Hemodynamic Effects of Nebulized Dexmedetomidine and Nebulized Lidocaine in Children undergoing Fiberoptic Bronchoscopy

Abstract

Background & Objective: Several studies have shown that topical and intravenous Dexmedetomidine and Lidocaine can decrease pain and reduce consumption of analgesic drugs. However, Lidocaine may be accompanied with several side effects such as respiratory suppression, seizure, and cardiac arrhythmias. On the other hand, Dexmedetomidine has favorable properties such as low risk of apnea, analgesia, sympatholysis, and sedation. Therefore, the aim of this study was to compare the effects of nebulized Dexmedetomidine and nebulized Lidocaine on hemodynamic characteristics of the patients undergoing bronchoscopy. Materials & Methods: In the present randomized, double-blind study; 75 children (1-6 years old) undergoing fiber-optic bronchoscopy were allocated to three groups. Group 1 received nebulized solution containing 2 µg/kg of Dexmedetomidine. Group 2 received nebulized solution containing 4 mg/kg of Lidocaine 1%. Group 3 received nebulized solution containing 0.9% of normal saline as the control group. Heart rate, mean arterial blood pressure and SpO2, Bispectral Index (BIS) were measured and compared. BIS, indicating the depth of anesthesia was considered as a confounding factor. Statistical analysis was performed using SPSS 20. Results: The mean of arterial blood pressure and heart rate was significantly lower in group 1 compared to groups 2 and 3 during bronchoscopy (P<0.05). Blood oxygen saturation and sedation scores were significantly higher in group 1 compared to the other groups during bronchoscopy (P<0.05). Furthermore, the hemodynamic parameters were more stable in group 1 compared to the other groups during recovery. Conclusion: Premedication with nebulized Dexmedetomidine was significantly associated with more stable hemodynamic parameters and lower risk of side effects compared to nebulized Lidocaine in children undergoing fiberoptic bronchoscopy.

Safety and Efficacy of Dexmedetomidine for Bronchoscopy: A Systematic Review and Meta-Analysis

“…Dexmedetomidine loading dose was 1 µg/kg in five studies [ 22 , 23 , 27 , 28 , 29 ], 0.5 µg/kg in three studies [ 24 , 30 , 31 ], and 2 µg/kg in one study [ 32 ]. The included studies of dexmedetomidine were administered intravenously, with the exception of one study [ 32 ], which was administered by aerosol. The basic characteristics of the included studies are listed in Table 2 .…”

“…All the studies demonstrated a low risk in terms of random sequence generation, incomplete outcome data, and selective reporting. For a small number of studies with assigned sequence hidden [ 22 , 29 , 32 ], subjects and researchers blinded [ 22 ], and blinded outcome measures, the researchers were unable to assess the risk [ 27 , 29 , 32 ]. Only one study because of allocation concealment, subjects, and operators’ implementation blindness was unclear, and the outcome measures were assessed by the operators, so the results are high risk [ 22 ].…”

“…Nine studies have explored the relationship between the use of anesthetic drugs and hypoxemia during flexible bronchoscopy, including a total of 765 patients [ 22 , 23 , 24 , 27 , 28 , 29 , 30 , 31 , 32 ]. Hypoxemia is defined as displaying SpO2 < 90% for more than 30 s, and it can be controlled by increasing the oxygen flow rate to 6 L/min or by performing mandibular support if necessary.…”

“…Five studies explored hypertension, including a total of 477 patients [ 22 , 24 , 27 , 29 , 32 ]. Hypertension is defined as a systolic blood pressure (SBP) > 180 mmHg, diastolic blood pressure (DBP) > 100 mmHg, or blood pressure 20% higher than the baseline arterial pressure.…”

“…Five studies discussed hypotension, including a total of 440 patients [ 23 , 24 , 27 , 29 , 32 ]. Hypotension is defined as SBP < 90 mmHg or mean arterial pressure < 60 mmHg or 20% below the baseline arterial pressure, which can be treated with ephedrine 5–10 mg injection [ 24 , 29 ].…”