Is hypertonic saline resuscitation safe in 'uncontrolled' hemorrhagic shock?

Hypertonic saline treatment of hemorrhagic shock (HS) results in increased systemic blood pressure, cardiac output, and splanchnic blood flow. To determine whether this elevation in blood pressure and flow would augment blood loss from injured intra-abdominal vessels and thus enhance mortality rate, "controlled" HS was induced by bleeding of 20 ml/kg from an arterial cannula that was immediately occluded after hemorrhage, and "uncontrolled" HS was induced by incision of three major radicals of the ileocolic artery leading to continuous intra-abdominal blood loss. Seventy rats were divided into eight groups: Group I (n = 5) underwent carotid artery and jugular vein cannulation and was observed for 3 hr; in Group II (n = 10) "controlled" HS was induced by arterial hemorrhage of 20 ml/kg; in Group III (n = 7) "controlled" HS was treated by 5 ml/kg NaCl 0.9%; in Group IV (n = 8) "controlled" HS was treated by 5 ml/kg NaCl 7.5%; in Group V (n = 4) midline laparotomy and identification of the ileocolic artery was performed; in Group VI (n = 9) "uncontrolled" HS was induced by incision of three major branches of the ileocolic artery; in Group VII (n = 9) "uncontrolled" HS was treated by 5 ml/kg NaCl 0.9%, and in Group VIII (n = 18) "uncontrolled" HS was treated by 5 ml/kg NaCl 7.5%. In untreated "controlled" HS (Group II), mean arterial pressure (MAP) fell to 35 torr followed by a spontaneous rise to 62 torr (p less than 0.001) after 3 hr with a survival of 80% of the animals.(ABSTRACT TRUNCATED AT 250 WORDS)