Influence of hypertonic saline on bacterial translocation in controlled hemorrhagic shock

Translocation of enteric bacteria has been described in rats following hemo rrhagic shock (HS). The aim of the present study was to evaluate the effect of hypertonic saline (HTS) on bacterial translocation(BT) in the setting o f controlled HS in rats. The study included 2 arms. Arm I was a qualitative assessment of translocation. Sixty-eight anesthetized animals were studied . The rats were divided into 5 groups. Group I (n = 10) was sham shock cont rols. In groups II-V, HS was induced by arterial bleeding to mean arterial pressure (MAP) of 35-45 mmHg, which was maintained for 30 min. The animals were then allocated into 4 groups: group II (n = 19) untreated HS; group II I (n = 13) normal saline (NS) treated; group IV (n = 13) MTS-treated; and g roup V (n = 13) HTS and blood treated. Mesenteric lymph nodes, liver, splee n, portal, and systemic blood were sent for culture after 24 h. Translocati on occurred if enteric bacteria were cultured from at least one site. Arm I I was a quantitative assessment of translocation. Two groups were studied: untreated HS (n = 7) and MTS treated (n = 6). In the qualitative arm, the 2 4-h mortality in untreated rats (group II) was 31.5% compared to 5.1% in tr eated animals (groups II-V) (P = 0.01). No BT was detected in control anima ls (group I). BT after HS was not different between groups II, III, and IV (92.3%, 91.6%, and 100%, respectively). Group V showed fewer translocations than groups II-IV, a difference that was especially significant compared w ith group IV (P = 0.039). However, BT to distant sites (systemic blood and spleen) was significantly tower in group V than in groups II-IV(P < 0.05). In the quantitative arm, the mortality rate was 16.7% in the untreated grou p. Although no qualitative significant difference in the translocation rate was found between the two groups (67% in untreated animals vs. 50% in HTS treated), there was significant quantitative difference: in MTS-treated gro up a significantly lesser bacteria translocated than in untreated animals ( 0.4 x 10(5) cfu/g VS. 4.2 x 10(5) cfu/g, respectively [P = 0.001]). We conc luded that whereas assessed qualitatively, in this model of severe HS in ra ts, the hemorrhagic insult itself resulted in BT in most animals and treatm ent with NS, HTS, and blood resulted in reduced early mortality but did not alter significantly the translocation rate. Only the combination of HTS an d blood resulted in reduced BT to distant sites. However, quantitative asse ssment showed that HTS significantly reduced the number of translocating ba cteria.