title: Remifentanil, fentanyl, or the combination in surgical procedures in the United States: predictors of use in patients with organ impairment or obesity.
abstract: BACKGROUND
  Remifentanil has a rapid onset and short duration of action, predictable pharmacokinetic/pharmacodynamic profile, and unlike fentanyl, does not accumulate with repeated or prolonged administration. This study evaluated predictors of remifentanil use in surgical patients with renal or hepatic impairment, or obesity in the United States who received remifentanil, fentanyl, or the combination.
  
  
  METHODS
  Data (2010) from the US Healthcare National Inpatient Database, State Inpatient Database, State Ambulatory Surgery Database, and private hospital and Medicaid databases were used in this analysis. Patients included had presence of hepatic or renal disease, and/or obesity and were >5 and ≤80 years of age.
  
  
  RESULTS
  In 2010, 9,274 patients with renal impairment, 1,896 with hepatic impairment, and 6,278 with obesity were identified. The percentage of surgical patients diagnosed with renal disease, hepatic disease, or obesity who received remifentanil was 41, 28, and 35%, respectively; 29, 17, and 22% received both remifentanil and fentanyl, and 30, 55, and 43% received fentanyl alone, respectively. In patients with renal or hepatic disease the probability of remifentanil use was greater for persons aged >50 years, with Medicare as primary payer, or who were diagnosed with obesity (p < 0.05 all comparisons). In obese patients, the probability of remifentanil use was greater for persons aged >50 years or female (both p < 0.05). For all 3 disease states, the probability of remifentanil use was lower for those receiving epidural anesthesia or with Medicaid as primary payer (p < 0.05 all comparisons).
  
  
  CONCLUSIONS
  Remifentanil in combination with fentanyl is used less than fentanyl in surgical patients with hepatic impairment or obesity. This is inconsistent with the fact that the pharmacokinetic/pharmacodynamic features of remifentanil suggest it is the preferred intraoperative opioid in these patients. Predictors of remifentanil use in patients with renal or hepatic impairment, or obesity include older age, obesity, and Medicare as primary payer. Remifentanil in combination with fentanyl was significantly less utilized than fentanyl in persons with Medicaid as primary payer even though there was a disproportionate enrollment of beneficiaries with renal or hepatic disease, or obesity in state Medicaid programs.
authors.affiliation: College of Pharmacy, Midwestern University, Glendale, AZ, USA, dsclar@midwestern.edu.
authors.forename: David Alexander
authors.initials: DA
authors.lastname: Sclar
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D004359:Drug Therapy, Combination; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage*; D006801:Humans; D007674:Kidney Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000601:surgery; D008107:Liver Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000188:drug therapy* / Q000453:epidemiology / Q000601:surgery; D010149:Postoperative Pain / Q000453:epidemiology / Q000517:prevention & control*; D010880:Piperidines / Q000008:administration & dosage*; D011237:Predictive Value of Tests; D000077208:Remifentanil; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
chemical_list: D000701:Analgesics, Opioid; D018686:Anesthetics, Intravenous; D010880:Piperidines; D000077208:Remifentanil; D005283:Fentanyl