title: Hyperlactatemia, increased osmolar gap, and renal dysfunction during continuous lorazepam infusion.
abstract: OBJECTIVE
  To review effects of the vehicle of lorazepam, propylene glycol, in regard to lactate, osmolarity, and renal dysfunction.
  
  
  METHODS
  Case report.
  
  
  METHODS
  Intensive care unit of a Level I trauma center. Patient A 36-yr-old Hispanic man who developed severe respiratory failure and required high-dose lorazepam for sedation. The patient was ventilated with low tidal volumes in a lung-protective fashion, with resultant "permissive hypercapnia." Lactates and osmolalities rose on initiation and fell, as expected, on discontinuation of the lorazepam infusion. However, there was no renal compensation for the hypercapnia except while the patient was not receiving lorazepam.
  
  
  RESULTS
  Serial osmolalities, lactates, serum bicarbonate, PaCO2, and pH were measured during lorazepam infusion. Rise and fall of serum lactate and osmolality closely correlated with lorazepam. Serum bicarbonate rose significantly while the patient was not receiving lorazepam in response to hypercarbia and failed to rise while the patient was receiving lorazepam.
  
  
  CONCLUSIONS
  The vehicle of lorazepam, propylene glycol, can cause hyperlactatemia and elevated osmolar gaps. However, propylene glycol may also interfere with renal tubular function and may blunt renal compensation for respiratory acidosis.
authors.affiliation: R Adams Cowley Shock Trauma Center, University of Maryland Medicine, Baltimore, USA.
authors.forename: H N
authors.initials: HN
authors.lastname: Reynolds
authors.forename: P
authors.initials: P
authors.lastname: Teiken
authors.forename: M E
authors.initials: ME
authors.lastname: Regan
authors.forename: N M
authors.initials: NM
authors.lastname: Habashi
authors.forename: C
authors.initials: C
authors.lastname: Cottingham
authors.forename: M
authors.initials: M
authors.lastname: McCunn
authors.forename: T M
authors.initials: TM
authors.lastname: Scalea
mesh_terms: D000328:Adult; D001639:Bicarbonates / Q000097:blood; D016292:Procedural Sedation; D006801:Humans; D007262:Infusions, Intravenous; D007684:Kidney Tubules / Q000187:drug effects*; D019344:Lactic Acid / Q000097:blood*; D008140:Lorazepam / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy; D014677:Pharmaceutical Vehicles; D019946:Propylene Glycol / Q000008:administration & dosage / Q000009:adverse effects*; D012121:Respiration, Artificial; D014882:Water-Electrolyte Balance / Q000187:drug effects* / Q000502:physiology
chemical_list: D001639:Bicarbonates; D014677:Pharmaceutical Vehicles; D019344:Lactic Acid; D019946:Propylene Glycol; D008140:Lorazepam