Infusion of hypertonic saline (7.5% NaCl) causes minor immunological changes in normovolaemic women.
BACKGROUND
Haemorrhagic shock is treated effectively by infusion of hypertonic saline/colloid solutions. Furthermore, previous studies found hypertonicity to affect immune responses in animals and in human blood cell cultures. It is unknown, however, whether hypertonic saline infusion affects immune responses in humans.


METHODS
In a randomized double-blind study, we infused 4 ml kg-1 of 7.5% NaCl or 0.9% NaCl over 10 min in 20 fasting women before hysterectomy. We collected peripheral blood at baseline, 30, and 120 min after start of the infusion and before surgery for the determination of leucocyte and differential count; lymphocyte subtypes; neutrophil chemotaxis; elastase concentration; and the cytokine's tumour necrosis factor-alpha (TNFalpha), interleukin (IL)-1beta, IL-6, IL-8, IL-1 receptor antagonist (IL-1ra), and IL-10. Phytohaemagglutinin (PHA)-induced lymphocyte proliferation and natural killer cell cytotoxicity were measured before and 120 min after infusion.


RESULTS
Compared with normal saline, infusion of hypertonic saline temporarily increased the number of B cells in peripheral blood (P < 0.01); increased the concentration of plasma elastase, a marker of neutrophil degranulation (P < 0.05); and decreased the number of circulating neutrophils (P < 0.001). No other effects were detected in the measured immunological parameters.


CONCLUSIONS
The immunological consequences of hypertonic saline infusion seem to be modest and are unlikely to cause any clinical effects, at least in normovolaemic women.
Kølsen-Petersen
J A
JA
Department of Anaesthesia and Intensive Care, Viborg County Hospital, 8800 Viborg, Denmark. jaakp@dadlnet.dk
Nielsen
J O D
JO
Bendtzen
K
K
Tonnesen
E
E
D000293:Adolescent; D000328:Adult; D000368:Aged; D003602:Cytotoxicity, Immunologic; D004311:Double-Blind Method; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007109:Immunity / Q000187:drug effects*; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology; D007958:Leukocyte Count; D008875:Middle Aged; D011446:Prospective Studies; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*
D012462:Saline Solution, Hypertonic