Comparing dexmedetomidine with midazolam for sedation of patients in the ICU

Effect of dexmedetomidine and midazolam for flexible fiberoptic bronchoscopy in intensive care unit patients: A retrospective study

This study aimed to investigate the clinical effectiveness of dexmedetomidine and midazolam for sedation of intensive care unit (ICU) patients requiring flexible fiberoptic bronchoscopy (FFB).This retrospective cohort study included 148 patients from the third ICU ward of the Second Affiliated Hospital of Harbin Medical University (Harbin, China) who received simultaneous invasive mechanical ventilation and FFB between March 2012 and December 2014. Patients were divided into dexmedetomidine (n  =  72) and midazolam (n  =  76) groups according to sedative mode. The sedative effects, incidence of adverse events, and bronchoscopist satisfaction scores were compared between groups.During FFB, total sedation time and total time of FFB were significantly shorter in the midazolam group (P < .001, respectively), with a lower percentage of these patients requiring propofol for remedial sedation (P < .001). The incidence of FFB-related adverse events (including bronchospasm, cough, and decreased oxygen saturation) was significantly higher in dexmedetomidine group compared with midazolam group (P  =  .007, .014 and .008, respectively). However, the incidence of other adverse events was not significantly different between groups. In addition, bronchoscopist satisfaction scores were significantly higher in the midazolam compared with dexmedetomidine group (7.72 ± 1.65 vs 7.08 ± 1.77; P  =  .030).For sedation of ICU patients during FFB, combination of midazolam and dexmedetomidine demonstrated an enhanced sedative effect, lower incidence of adverse events, and higher bronchoscopist satisfaction score compared with dexmedetomidine alone, thus represents a suitable alternative sedative for FFB patients.

Dexmedetomidine reduces cranial temperature in hypothermic neonatal rats

BACKGROUND

The α2-adrenergic agonist dexmedetomidine (DEX) is increasingly used for prolonged sedation of critically ill neonates, but there are currently no data evaluating possible consequences of prolonged neonatal DEX exposure. We evaluated the pharmacokinetics and histological consequences of neonatal DEX exposure.

METHODS

DEX was administered (s.c.) to naive (uninjured) neonatal Lewis rats to provide acute (25 µg/kg, ×1) or prolonged (25 µg/kg three times daily, ×2 or ×4 d) exposure. Therapeutic hypothermia was simulated using a water-cooled blanket. Cranial temperatures were measured using an infrared thermometer. DEX concentrations were measured by LC-MS in plasma and homogenized brainstem tissue for pharmacokinetic analysis. Cortex, cerebellum, and brainstem were evaluated for evidence of inflammation or injury.

RESULTS

Prolonged neonatal DEX exposure was not associated with renal or brain pathology or indices of gliosis, macrophage activation, or apoptosis in either hypothermic or control rats. Plasma and brain DEX concentrations were tightly correlated. DEX peaked within 15 min in brain and reduced cranial temperature from 32 to 30 °C within 30 min after injection in cooled rats.

CONCLUSION

Prolonged DEX treatment in neonatal rats was not associated with abnormal brain histology. These data provide reassuring preliminary results for using DEX with therapeutic hypothermia to treat near-term brain injury.