title: Effect of transient warming of red blood cells for up to 24 h: in vitro characteristics in CPD/saline-adenine-glucose-mannitol environment.
abstract: OBJECTIVE
  There are few studies on transient warming of red blood cells (RBCs). Occasional storage outside restricted temperature range often results in destroying of the RBC unit, even after a short period of time due to national guidelines. This study evaluates the in vitro effects associated with such accidental warming on RBCs stored in saline-adenine-glucose-mannitol (SAGM) and prepared within 8 h after blood collection.
  
  
  METHODS
  This study includes both repeated short-term exposure of RBCs to room temperature for 6 h as wells as warming for either 6, 12, 18 or 24 h after 1 week or after 3 weeks of storage in two separate studies. RBCs were stored for 42 days. We weekly measured pH, K(+) , glucose, lactate, haemolysis, red cell ATP and 2,3-diphosphoglycerate.
  
  
  RESULTS
  The lowest individual ATP value observed in any of the groups of warmed units was 2·6 μmol/g haemoglobin. Increased haemolysis in warmed units was noted in two of the studies. None of the individual units exceeded the European maximum limit of 0·8% haemolysis.
  
  
  CONCLUSIONS
  Our results suggest that quality of RBCs after transient warming will be maintained at acceptable levels specified in standards and in previous studies. However, increased haemolysis was observed when transient warming occurred during the second part of the storage period of 6 weeks suggesting that RBCs are more vulnerable to warming by the end of storage.
authors.affiliation: Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Gulliksson
authors.forename: A-S
authors.initials: AS
authors.lastname: Nordahl-Källman
mesh_terms: D019794:2,3-Diphosphoglycerate / Q000737:chemistry; D000225:Adenine / Q000737:chemistry; D001793:Blood Preservation / Q000379:methods*; D004781:Environmental Exposure; D004912:Erythrocytes; D005947:Glucose / Q000737:chemistry; D006461:Hemolysis; D006358:Hot Temperature; D006801:Humans; D008353:Mannitol / Q000737:chemistry; D019188:Organ Preservation Solutions / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry
chemical_list: D019188:Organ Preservation Solutions; D019794:2,3-Diphosphoglycerate; D008353:Mannitol; D012965:Sodium Chloride; D005947:Glucose; D000225:Adenine
keywords: haemolysis; in vitro study; red blood cells; room temperature; warming