Hypernatremic suppression of neutrophils.

Phagocytic and bactericidal activities are important functions of the human polymorphonuclear leucocytes (PMNL) as the host defence against burn wound infection. The zone of stasis, just below the zone of coagulation, is a site of interaction between invading bacteria and PMNL. For many reasons the osmotic pressure at this site is elevated. In this study we evaluated the in vitro phagocytic and bactericidal activities of PMNL under hypernatremic conditions. At a sodium concentration of 180 mEq/l, phagocytic activity was suppressed. Although on average superoxide production was maintained within the normal range, it was suppressed in three of the ten cases studied. We conclude that the hypernatremic condition may weaken local defence against burn wound infection at the zone of stasis and may be a risk factor for burn wound sepsis.