Background A great number of children suffer from blast lung injury (BLI) worldwide, but there is a little basic study on the topic. Methods Infant (4‐week‐old) and adult New Zealand rabbits were selected. Comparison of BLI characteristics: 16 infant rabbits were randomly divided into a 4.0 MPa group (n = 8, “IRG4.0MPa”) and a 4.5 MPa group (n = 8, “IRG4.5MPa”) and exposed to shock waves of those magnitudes. Eight adult rabbits were exposed to 4.0 MPa (“ARG4.0MPa”). The severity of BLI was compared among these three groups. Comparison of impact characteristics between infant and adult rabbits at the same scale of BLI: infant and adult rabbits were randomly divided into a control group (n = 8 per age group) and a blast injury group (n = 40 infants, “IRG4.0MPa”; n = 40 adults, “ARG4.5MPa”). The vital signs, physiological indicators, gross anatomy, and light microscope pathology were observed. Results The differences in lung injury severity and in abbreviated injury scale (AIS) scores between IRG4.5MPa (87.5%, AIS 4.13 ± 0.64) and ARG4.0MPa (75.5%, AIS 4.18 ± 0.75) were not statistically significant (P > .05); IRG4.0MPa (12.5%, AIS 3.38 ± 0.52) showed a lower proportion of lung injury and lower AIS scores than the others (P < .01). All rabbits showed languor immediately after the injury. The lungs showed tissue rupture, extensive patchy hemorrhage, edema, and inflammatory infiltration. The increase in lung water content was much higher in the IRG than in the ARG (P < .01). Conclusion Infant rabbits show better tolerance to lung injury caused by shock waves; infant rabbits show more disturbance on pathophysiological response than adult rabbits.

Background: A significant part of blast injury is accompanied by hemorrhagic shock (BS), while research on its fluid resuscitation strategies have not been reported. Although blood products are usually recommended in most resuscitation cases, they are less available in certain conditions. To this end, here, we focused on a widely used and more accessible fluid type- crystalloid fluid, in BS treatment. Methods: We conducted studies in rats comparing the therapeutic effects of 3 different crystalloid solutions at different time points after BS, and explored the underlying mechanisms. Generally, the survival rates gradually dropped along with the time when fluid resuscitation was given. Results: Among different types of solution, the hypertonic saline (HS) group showed th objective: A significant part of blast injury is accompanied by hemorrhagic shock (BS), while researches on its fluid resuscitation strategies have not been reported. Although blood products are usually recommended in most resuscitation cases, they are less available in certain conditions. To this end, here we focused on a widely used and more accessible fluid type- crystalloid fluid, in BS treatment. Results: Among different types of solution, the hypertonic saline (HS) group showed the highest survival rates. The lactated Ringer’s solution (LR) only displayed lifesaving effect at 0.5h resuscitation time point. Moreover, it is worth noting that the survival rates of the normal saline (NS) group at all the time points were lower than the non-treatment control. Mechanism study in rats indicated that the therapeutic differences may be caused by varied degrees of pulmonary edema and inflammatory responses under different crystalloid fluid resuscitation. Conclusions: In conclusion, we assessed the effects and investigated the mechanisms of different crystalloid fluid resuscitation strategies for BS for the first time, which potentially contributes to the establishment of guidance for crystalloid fluid resuscitation of BS patients.