title: Mild Sedation Exacerbates or Unmasks Focal Neurologic Dysfunction in Neurosurgical Patients with Supratentorial Brain Mass Lesions in a Drug-specific Manner.
abstract: BACKGROUND
  Sedation is commonly used in neurosurgical patients but has been reported to produce transient focal neurologic dysfunction. The authors hypothesized that in patients with frontal-parietal-temporal brain tumors, focal neurologic deficits are unmasked or exacerbated by nonspecific sedation independent of the drug used.
  
  
  METHODS
  This was a prospective, randomized, single-blind, self-controlled design with parallel arms. With institutional approval, patients were randomly assigned to one of the four groups: "propofol," "midazolam," "fentanyl," and "dexmedetomidine." The sedatives were titrated by ladder administration to mild sedation but fully cooperative, equivalent to Observer's Assessment of Alertness and Sedation score = 4. National Institutes of Health Stroke Scale (NIHSS) was used to evaluate the neurologic function before and after sedation. The study's primary outcome was the proportion of NIHSS-positive change in patients after sedation to Observer's Assessment of Alertness and Sedation = 4.
  
  
  RESULTS
  One hundred twenty-four patients were included. Ninety had no neurologic deficits at baseline. The proportion of NIHSS-positive change was midazolam 72%, propofol 52%, fentanyl 27%, and dexmedetomidine 23% (P less than 0.001 among groups). No statistical difference existed between propofol and midazolam groups (P = 0.108) or between fentanyl and dexmedetomidine groups (P = 0.542). Midazolam and propofol produced more sedative-induced focal neurologic deficits compared with fentanyl and dexmedetomidine. The neurologic function deficits were mainly limb motor weakness and ataxia. Patients with high-grade gliomas were more susceptible to the induced neurologic dysfunction regardless of the sedative.
  
  
  CONCLUSIONS
  Midazolam and propofol augmented or revealed neurologic dysfunction more frequently than fentanyl and dexmedetomidine at equivalent sedation levels. Patients with high-grade gliomas were more susceptible than those with low-grade gliomas.
authors.affiliation: From the Department of Anesthesiology (N.L., R.H.) and Department of Critical Care Medicine (J.Z.), Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, California (A.W.G.).
authors.forename: Nan
authors.initials: N
authors.lastname: Lin
authors.forename: Ruquan
authors.initials: R
authors.lastname: Han
authors.forename: Jianxin
authors.initials: J
authors.lastname: Zhou
authors.forename: Adrian W
authors.initials: AW
authors.lastname: Gelb
mesh_terms: D000328:Adult; D020927:Dexmedetomidine / Q000009:adverse effects; D005260:Female; D005283:Fentanyl / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects*; D008297:Male; D008874:Midazolam / Q000009:adverse effects; D008875:Middle Aged; D009422:Nervous System Diseases / Q000139:chemically induced* / Q000175:diagnosis / Q000453:epidemiology*; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011446:Prospective Studies; D016037:Single-Blind Method; D015173:Supratentorial Neoplasms / Q000453:epidemiology* / Q000601:surgery*; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine; D008874:Midazolam; D005283:Fentanyl