Emergency rescue of a patient with hemorrhagic shock caused by superior mesenteric artery rupture:A case report

BACKGROUND Superior mesenteric artery(SMA)injuries rarely occur during blunt abdominal injuries,with an incidence of<1%.The clinical manifestations mainly include abdominal hemorrhage and peritoneal irritation,which progress rapidly and are easily misdiagnosed.Quick and accurate diagnosis and timely effective treatment are greatly significant in managing emergent cases.This report describes emergency rescue by a multidisciplinary team of a patient with hemorrhagic shock caused by SMA rupture.CASE SUMMARY A 55-year-old man with hemorrhagic shock presented with SMA rupture.On admission,he showed extremely unstable vital signs and was unconscious with a laceration on his head,heart rate of 143 beats/min,shallow and fast breathing(frequency>35 beats/min),and blood pressure as low as 20/10 mmHg(1 mmHg=0.133 kPa).Computed tomography revealed abdominal and pelvic hematocele effusion,suggesting active bleeding.The patient was suspected of partial rupture of the distal SMA branch.The patient underwent emergency mesenteric artery ligation,scalp suture,and liver laceration closure.In view of conditions with acute onset,rapid progression,and high bleeding volume,key points of nursing were conducted,including activating emergency protocol,opening of the green channel,and arranging relevant examinations with various medical staff for quick diagnosis.The seamless collaboration of the multidisciplinary team helped shorten the preoperative preparation time.Emergency laparotomy exploration and mesenteric artery ligation were performed to mitigate hemorrhagic shock while establishing efficient venous accesses and closely monitoring the patient’s condition to ensure hemodynamic stability.Strict measures were taken to avoid intraoperative hypothermia and infection.CONCLUSION After 3.5 h of emergency rescue and medical care,bleeding was successfully controlled,and the patient’s condition was stabilized.Subsequently,the patient was transferred to the intensive care unit for continuous monitoring and treatment.On the sixth day,the patient was weaned off the ventilator,extubated,and relocated to a specialized ward.Through diligent medical intervention and attentive nursing,the patient made a full recovery and was discharged on day 22.The follow-up visit confirmed the patient’s successful recovery.

Hemorrhagic shock due to submucosal esophageal hematoma along with mallory-weiss syndrome:A case report

BACKGROUND Esophageal submucosal hematoma is a rare condition.Although the exact etiology remains uncertain,vessel fragility with external factors is believed to have led to submucosal bleeding and hematoma formation;the vessel was ruptured by a sudden increase in pressure due to nausea,and the hematoma was enlarged by antiplatelet or anticoagulant therapy.Serious conditions are rare,with a better prognosis.We present the first known case of submucosal esophageal hematoma-subsequent hemorrhagic shock due to Mallory-Weiss syndrome.CASE SUMMARY A 73-year-old female underwent endovascular treatment for an unruptured cerebral aneurysm.The patient received aspirin and clopidogrel before surgery and heparin during surgery,and was well during the surgery.Several hours after returning to the ICU,she complained of chest discomfort,vomited 500 m L of fresh blood,and entered hemorrhagic shock.Esophageal submucosal hematoma with Mallory-Weiss syndrome was diagnosed through an endoscopic examination and computed tomography.In addition to a massive fluid and erythrocyte transfusion,we performed a temporary compression for hemostasis with a Sengstaken-Blakemore(S-B)tube.Afterwards,she became hemodynamically stable.On postoperative day 1,we performed an upper gastrointestinal endoscopy and confirmed no expansion of the hematoma nor any recurring bleeding;therefore,we removed the S-B tube and clipped the gastric mucosal laceration at the esophagogastric junction.We started oral intake on postoperative day 10.The patient made steady progress,and was discharged on postoperative day 33.CONCLUSION We present the first known case of submucosal esophageal hematoma subsequent hemorrhagic shock due to Mallory-Weiss syndrome.

Effects of environmental hypothermia on hemodynamics and oxygen dynamics in a conscious swine model of hemorrhagic shock

BACKGROUND:Hypothermia is associated with poor outcome in trauma patients;however,hemorrhagic shock(HS)model with anesthetized swine was different from that of clinical reality.To identify the effects of environmental hypothermia on HS,we investigated hemodynamics and oxygen dynamics in an unanesthetized swine model of HS under simulating hypothermia environment.METHODS:Totally 16 Bama pigs were randomly divided into ambient temperature group(group A)and low temperature group(group B),8 pigs in each group.Venous blood(30 mL/kg)was continuously withdrawn for more than 15 minutes in conscious swine to establish a hemorrhagic shock model.Pulmonary arterial temperature(Tp),heart rate(HR),mean arterial pressure(MAP),pulmonary arterial pressure(PAP),pulmonary arterial wedge pressure(PAWP),central venous pressure(CVP),cardiac output(CO),hemoglobin(Hb),saturation of mixed venous blood(SvO_2)and blood gas analysis were recorded at the baseline and different hemorrhagic shock time(HST).The whole body oxygen delivery indices,DO_2l and VO_2l,and the O_2 extraction ratio(O_2ER)were calculated.RESULTS:Core body temperature in group A decreased slightly after the hemorrhagic shock model was established,and environmental hypothermia decreased in core body temperature.The mortality rate was significantly higher in group B(50%)than in group A(0%).DO_2l and VO_2l decreased significantly after hemorrhage.No difference was found in hemodynamics,DO_2l and VO_2l between group A and group B,but the difference in pH,lactic acid and O_2ER was significant between the two groups.CONCLUSION:Environmental hypothermia aggravated the disorder of oxygen metabolism after hemorrhagic shock,which was associated with poor prognosis.

Effect of Hypertonic Versus Isotonic Saline Resuscitation on Heme Oxygenase-1 Expression in Visceral Organs Following Hemorrhagic Shock in Rats

To compare the early effects of hypertonic and isotonic saline resuscitation on heme oxygenase-1 （HO-1） expression in organs of rats with hemorrhagic shock. Rats were randomly divided into hypertonic saline resuscitation （HTS）, normal saline resuscitation （NS） and sham groups. HO-1 mRNA, protein expression and apoptosis were evaluated in organs. In the HTS group, significant difference was noted in HO-1 protein in small intestinal mucosa and liver compared with the NS and sham groups, and in HO-1 mRNA in liver and kidney compared with the sham group. The apoptosis of small intestinal mucosa, liver, heart, and lung was significantly lower in the HTS group than that in the NS group. In this study, small volume resuscitation with HTS can efficiently up-regulate the expression level of HO-1 in small intestinal mucosa and liver, which may be one of the mechanisms alleviating organ damage.

Effects of different infusion volumes on hemo-dynamics of portal hypertension canines after hemorrhagic shock

BACKGROUND: Portal hypertension ( PHT) with upper gastrointestinal hemorrhage as its chief complication is a very common disease with great harm to humans. The effects of infusion volume, speed, and type on hemody- namics in case of cirrhosis, PHT esophageal variceal bleed- ing, and their mechanism should be clarified. This study was designed to assess the effects of different infusion vo- lumes on hemodynamics of PHT canines after hemorrhagic shock (HS). METHODS: PHT canine models were made by chronic embolization via coarctating half of the main portal vein with silk suture. Two weeks later, the models were subjec- ted to hemorrhagic shock by quick femoral artery venesec- tion. The canines were divided into two groups to resusci- tate : one to receive a large volume of infusion (n =6) (large volume infusion group) and the other to receive a small vo- lume of infusion (n =6) (small volume infusion group). Hemodynamic indexes of PHT canines after HS and infu- sion were observed closely. RESULTS: The PHT canines showed a series of hemody- namical changes in hemorrhagic shock stage, which aggra- vated hemodynamical disorder in PHT. After quick infu- sion, mean arterial pressure (MAP), inferior vena cava pressure (IVCP), portal venous pressure ( PVP), portal vein pressure gradient ( PVPG), portal vein blood flow ( PVBF), hepatic artery blood flow ( HABF) and hepatic blood flow (HBF) increased significantly. These indexes in the large volume infusion group were higher than those in the small volume infusion group. Portal vascular resistance (PVR), splanchnic vascular resistance ( SVR), hepatic arte- rial resistance ( HAR) decreased significantly, but PVP, PVPG, PVBF, HABF and HBF showed a rebounding in- crease above the baseline values in the large volume infu- sion group. The changes of PVP, PVPG, PVBF, HABF and HBF were in parallel with those of MAP and inferior vena cava pressure (IVCP), without a rebounding increase in the small volume infusion group. In the large volume in- fusion group PVPG increased earlier and more significantly than did PVP; moreover PVPG exceeded the baseline by 13% , making the possibility of rebleeding great. In the small volume infusion group, PVPG was lower than the baseline by more than 22% , indicating a small possibility of rebleeding. SVR and HAR were lower in the large volume infusion group. PVP, PVPG, PVBF, HABF and HBF were positively correlated with accumulated volume of vein infusion. PVR showed a positive correlation with accumu- lated volume of vein infusion in the small volume infusion group. HAR was negatively correlated with accumulated volume of vein infusion in the large volume infusion group. CONCLUSIONS: PHT canines after HS, resuscitated by vein infusion, may show a rebounding increase of PVP, PVPG, PVBF, HABF and HBF above the baseline values in the large volume infusion group but not in the small vol- ume infusion group. A large volume infusion causes PVP, PVPG, PVBF, HABF and HBF to increase higher than does a small volume infusion.

Hemorrhagic shock due to ruptured lower limb vascular malformation in a neurofibromatosis type 1 patient:A case report

BACKGROUND Neurofibromatosis type 1(NF-1)is a common autosomal dominant genetic disorder.It is characterized by café-au-lait spots and cutaneous neurofibromas.Although NF-1 typically involves the skin,nerves,bones,and eyes,vascular manifestation in the form of devastating hemorrhage can occur rarely.CASE SUMMARY We present the case of a 47-year-old female with NF-1 who had a ruptured right lower limb arterial malformation.She presented with sudden right lower limb swelling for two hours and symptoms of hemorrhagic shock on admission.The physical examination revealed a right lower limb presenting as elephantiasis and visible dark-brown pigmentation over a large area.Computed tomography angiography showed right lower limb arteriovenous malformation.Therefore,the patient underwent emergency right lower limb digital subtraction angiography(DSA)and vascular embolization after blood transfusions.However,after DSA,vascular embolization,and repeated blood transfusions,the anemia and right lower limb swelling and tenderness did not improve.As a result,the patient underwent right lower extremity above-knee amputation.After amputation,the patient's hemoglobin level improved significantly without blood transfusion,and she was discharged from the hospital after the incision healed.Postoperative pathological examination suggested neurogenic tumors.No other complications had occurred 1-year follow-up.CONCLUSION Vascular malformation and rupture are fatal complications of NF-1.Embolization may not provide complete relief,the patient might need to undergo neurofibroma resection or amputation.

Effects of GLP on Intestinal Mucosal Injury and the Change of TNF-α Content in Hemorrhagic Shock Rabbits

Objective To observe the intestinal mucosal injury and the change of TNF-αcontent in rabbits with hemorrhagic shock/reperfusion(HS-R)and the effects of ganoderma Lcidum polysaccharide(GLP)on them.Methods 30rabbits were made into hemorrhagic shock,then reperfused with different liquids.These rabbits were divided by random number table into three groups:sham operation group(Sham group),reperfusion with normal saline group(NS group),reperfusion with 1%GLP group(LS group).Bacterial translocation of blood and TNF-αcontent in serum were respectively observed at the time before shock,40 min after shock,40 min and 90 min after.TNF-αcontent in intestinal mucosa and the degree of intestinal mucosal injury were examined at 90 min post-resuscitation.Results 1 With the extension of reperfusion time,the positive rate of blood bacteria increased gradually in NS group,which was significantly higher than that of Sham group and LS group(P<0.05),meanwhile the degree of intestinal mucosal injury in NS group was more severe than that of Sham group and LS group too(P<0.05).2TNF-αcontent in serum of NS group and LS group were increased obviously compared with that before shock and in Sham group(P<0.05).TNF-αcontent in serum was further increased after reperfusion with NS,which was distinctly higher than that in LS group.TNF-αcontent in intestinal mucosa of NS group was significantly higher than that in LS group and Sham group too(P<0.05).Conclusion GLP can protect intestinal mucosa against HS-R injury,and its effects may relate with the change of TNF-αin hemorrhagic shock rabbits.

A Review of Nurses’ Perceptions of Traumatic Haemorrhagic Shock Management in Emergency Nursing

Haemorrhagic shock (HS) is a subset of hypovolaemic shock in which there is minimal to massive loss of blood either internally or externally in trauma or injured patients. Data from the World Health Organization (WHO) affirm that injuries account for over 5 million fatalities globally every year, and by 2030, injury mortality is predicted to rise severely. Public health research typically uses the KAP models, which may be divided into three parts: acquiring accurate knowledge, forming an attitude, and adopting behavior, to analyze people’s health behaviors and explain changes in them. This review is about the nurses’ perspectives of the concept of Knowledge, Attitude, and Practice (KAP) Model of hemorrhagic shock in trauma patients and assesses clinical practice tools used by nurses to keep an eye on patients who have the condition. Nurses’ knowledge of indications of shock is either high or very high. The knowledge of nurses was related to their training before working in accident and emergency units. The nurses’ attitude is considered significant, commendable, appropriate, and pertinent to the provision of care for a patient experiencing hemorrhagic shock. And the nurse’s practice of early patient identification, prompt and continuous monitoring, control of the bleeding source, maintenance of hemostasis, and the correction of significant blood loss that can occur quickly to cause death, are the strengths of management. .

Effect of tubastatin A on NLRP3 inflammasome activation in macrophages under hypoxia/ reoxygenation conditions

BACKGROUND:There are currently no effective drugs to mitigate the ischemia/reperfusion injury caused by fluid resuscitation after hemorrhagic shock(HS).The aim of this study was to explore the potential of the histone deacetylase 6(HDAC6)-specific inhibitor tubastatin A(TubA)to suppress nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation in macrophages under hypoxia/reoxygenation(H/R)conditions.METHODS:The viability of RAW264.7 cells subjected to H/R after treatment with different concentrations of TubA was assessed using a cell-counting kit-8(CCK8)assay.Briefly,2.5μmol/L TubA was used with RAW264.7 cells under H/R condition.RAW264.7 cells were divided into three groups,namely the control,H/R,and TubA groups.The levels of reactive oxygen species(ROS)in the cells were detected using fluorescence microscopy.The protein expression of HDAC6,heat shock protein 90(Hsp90),inducible nitric oxide synthase(iNOS),NLRP3,gasdermin-D(GSDMD),Caspase-1,GSDMD-N,and Caspase-1 p20 was detected by western blotting.The levels of interleukin-1β(IL-1β)and IL-18 in the supernatants were detected using enzyme-linked immunosorbent assay(ELISA).RESULTS:HDAC6,Hsp90,and iNOS expression levels were significantly higher(P<0.01)in the H/R group than in the control group,but lower in the TubA group than in the H/R group(P<0.05).When comparing the H/R group to the control group,ROS levels were significantly higher(P<0.01),but significantly reduced in the TubA group(P<0.05).The H/R group had higher NLRP3,GSDMD,Caspase-1,GSDMD-N,and Caspase-1 p20 expression levels than the control group(P<0.05),however,the TubA group had significantly lower expression levels than the H/R group(P<0.05).IL-1βand IL-18 levels in the supernatants were significantly higher in the H/R group compared to the control group(P<0.01),but significantly lower in the TubA group compared to the H/R group(P<0.01).CONCLUSION:TubA inhibited the expression of HDAC6,Hsp90,and iNOS in macrophages subjected to H/R.This inhibition led to a decrease in the content of ROS in cells,which subsequently inhibited the activation of the NLRP3 inflammasome and the secretion of IL-1βand IL-18.

Esketamine use for anesthesia induction in an ectopic pregnancy patient with hemorrhagic shock:a case report

Background Anesthesia induction is challenging in patients with hemodynamic instability.Esketamine has hypnotic,analgesic,and sympathomimetic effects and is the only anesthetic that can increase sympathetic tension.Therefore,it may be more suitable for patients with hypovolemic shock.Case summary A 40-year-old female patient presented to the emergency department with new-onset abdominal pain and vaginal bleeding for 2 hours.Menstruation of the patient was regular,her self-reported urine pregnancy test was positive half a month earlier,and she had been diagnosed at another hospital 12 days earlier based on a positive blood human chorionic gonadotropin test.Gynecological ultrasonography demonstrated no pregnancy sac in utero,confirming ectopic pregnancy.Emergency laparoscopy for ectopic pregnancy should be performed immediately.We administered esketamine for induction.Conclusion Esketamine-based total intravenous anesthesia results in mild hypotension in ectopic pregnancies with hemorrhagic shock.

Single Lung Acute Respiratory Distress Syndrome

Hydatid disease or echinococcosis is a zoonotic parasitic disease. The lungs are the second most commonly affected organ after the liver. Intrathoracic and extrapulmonary hydatid disease can affect the pleura, mediastinum, heart, diaphragm, and chest wall. The unusual location or complications of thoracic hydatid disease can present both a diagnostic problem and a therapeutic and surgical problem. We present results of a case of multilocular thoracic hydatid disease complicated by aortic wall erosion and cystic fistula in a 23-year-old patient who developed acute respiratory distress syndrome (ARDS) on the 4th day after emergency pneumonectomy. The surgery was carried out under the conditions of the auxiliary artificial circulation. This case represented a serious clinical situation with the highest risk to life. The need for immediate respiratory support was due to the development of severe respiratory failure, and the presence of direct and indirect harmful factors of ARDS. The correct choice of modes and techniques of mechanical ventilation resulted in significant and sustained improvement in gas exchange parameters without hemodynamic disorders with a further favorable outcome.

Early difference in apoptosis of intestinal mucosa of rats with severe uncontrolled hemorrhagic shock after three fluid resuscitation methods

Hemorrhagic shock is a common clinical emergency case. Successful treatment is usually accomplished by surgical control of hemorrhage and restoration of tissue perfusion. The fluid resuscitation method in the presurgical care of the hypotensive trauma patients is controversial. Current guidelines for presurgical treatment of patients with hemorrhagic shock recommend rapid volume resuscitation to normal blood pressure as quickly as possible.

Effects of glycine and methylprednisolone on hemorrhagic shock in rats

Background Methylprednisolone (MP), a synthetic glucocorticosteroid, has been broadly studied in experiments on endotoxin-induced shock and septic shock. This study was designed to ascertain whether glycine and MP can protect against organ injury and death caused by hemorrhagic shock, and to elucidate the underlying mechanisms of these protective effects in rats.Method To establish a shock model, Wistar rats were bled to maintain mean arterial pressure at 30-50 mmHg for 1 hour and subsequently resuscitated with the shed blood and normal saline. Just prior to resuscitation, the rats were randomly assigned to four groups: sham group (operation performed without inducing shock), shock group, shock+glycine group (glycine injected at the beginning of resuscitation) and shock+MP group (MP injected at the beginning of resuscitation).Results ① Seventy-two hours after resuscitation, the survival rate of rats from the shock group had decreased to 20%, while the survival rates of rats from the shock+glycine and shock+MP groups were 77.8% and 80%, respectively. The difference was significant (P<0.05). ② Eighteen hours after resuscitation, pathological alterations in the organs of the rats were apparent. In rats from the shock group, edema, interstitial leukocyte infiltration, and cellular degeneration occurred in the liver, lungs, kidneys, and heart. Glycine and MP reduced these pathological changes significantly. ③ Eighteen hours after resuscitation, the levels of creatine phosphokinase, transaminases, and creatine were elevated significantly in rats from the shock group, indicating injury to the heart, liver, and kidneys, while these levels were elevated only slightly in the shock+glycine and shock+MP groups. The differences were significant (P<0.01). ④ There were significant increases in intracellular calcium and production of tumor necrosis factor (TNF-α) by isolated Kupffer cells stimulated by endotoxin after hemorrhagic shock. These changes were completely prevented by glycine and MP (P<0.01). Conclusion Glycine and MP reduce organ injury and mortality caused by hemorrhagic shock by preventing increase of intracellular calcium levels in Kupffer cell, suppressing Kupffer cell activation, decreasing the production of TNF-α by Kupffer cells, and blocking systemic inflammatory responses.

Effect of Astragalus membranaceus injection on the activity of the intestinal mucosal mast cells after hemorrhagic shock-reperfusion in rats

Background The mechanism of mucosal damage induced by ischemia-reperfusion （IR） after hemorrhagic shock is complex; mast cells （MC） degranulation is associated with the mucosal damage. Astragalus membranaceus can protect intestinal mucosa against intestinal oxidative damage after hemorrhagic shock, and some antioxidant agents could prevent MC against degranulation. This study aimed to observe the effects of astragalus membranaceus injection on the activity of intestinal mucosal mast cells （IMMC） after hemorrhage shock-reperfusion in rats Methods Thirty-two Wistar rats were randomly divided into the normal group, model group, low dosage group, （treated with Astragalus membranacaus injection, 10 g crude medication/kg） and high dosage group （treated with Astragalus membranacaus injection, 20 g crude medication/kg）. The rat model of hemorrhagic shock-reperfusion was induced by hemorrhage for 60 minutes followed by 90 minutes of reperfusion. The animals were administrated with 3 ml of the test drug solution before reperfusion. At the end of study, intestinal pathology, ultrastructure of IMMC, and expression of tryptase were assayed. The levels of malondisldehyde （MDA）, TNF-α, histamine, and superoxide dismutase （SOD） activity in intestine were detected, and the number of IMMC was counted. Results The Chiu＇s score of the rats in the model group was higher than in other groups （P〈0.01）. The Chiu＇s score in the high dosage group was higher than that in the low dosage group （P〈0.05）. Hemorrhage-reperfusion induced IMMC degranulation： Astragalus membranaceus injection attenuated this degranulation. Expression of tryptase and the number of IMMC in the model group increased compared with the other groups （P〈0.01） and was significantly reduced by the treatments of Astragalus membranaceus injection at both doses. There was no significant difference between the two treatment groups （P〉0.05）. MDA content and concentration of TNF-α in the model group were higher than that in the other three groups （P〈0.05）, and the concentration of TNF-α in the low dosage group was higher than that in the high dosage group （P〈0.05）. SOD activity and the concentration of histamine in the model group were lower than the other three groups （P〈0.05）. There was a negative correlation between the Chiu＇s score and the concentration of histamine and a positive correlation between the Chiu＇s score and the concentration of TNF-α and between the SOD activity and the concentration of histamine in the four groups （P〈0.05）. Conclusion Astragalus membranaceus injection may reduce the damage to small intestine mucosa by inhibiting the activated IMMC after hemorrhagic shock.

Hypertonic saline resuscitation contributes to early accumulation of circulating myeloid-derived suppressor cells in a rat model of hemorrhagic shock

Background Hemorrhagic shock is usually associated with complicated immune and inflammatory responses, which are sometimes crucial for the prognosis. As regulators of the immune and inflammatory system; proliferation, migration, distribution and activation of myeloid-derived suppressor cells （MDSCs） are intimately linked to the inflammation cascade. Methods In a model of severe hemorrhagic shock, thirty-five rats were randomly divided into control, sham, normal saline resuscitation （NS）, hypertonic saline resuscitation （HTS）, and hydroxyethyl starch resuscitation （HES）, with seven in each group. MDSCs were analyzed by flow cytometric staining of CD11b/c＊Gra~ in peripheral blood mononuclear cells （PBMC）, spleen cell suspensions, and bone marrow nucleated cells （BMNC）. Simultaneously, the expressions of arginase-1 （ARG-1） and inducible nitric oxide synthase （iNOS） mRNA in MDSCs were evaluated by quantitative reverse transcription-polymerase chain reaction （qRT-PCR）. Results In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the MDSCs in the PBMC of NS, HTS and HES groups markedly increased, and MDSCs in BMNC of these groups decreased accordingly, significantly different to the control group. In hemorrhagic shock rats infused with HTS at the early resuscitation stage, MDSCs in PBMC increased about 2 and 4 folds, and MDSCs in BMNC decreased about 1.3 and 1.6 folds, as compared to the sham group respectively, with statistically significant difference. Furthermore, compared to the NS and HES groups, the MDSCs in PBMC of HTS group increased 1.6 and 1.8 folds with statistically significant differences; the MDSCs decrease in BMNC was not significant. However, there was no statistically significant difference in MDSCs of spleen among the five groups. In addition, compared to the control, sham, NS and HES groups, the ARG-1 and iNOS mRNA of MDSCs in PBMC, spleen and BMNC in the HTS group had the highest level of expression, but no statistically significant differences were noted. Conclusions In this model of rat with severe and controlled hemorrhagic shock, small volume resuscitation with HTS contributes to dramatically early migration and redistribution of MDSCs from bone marrow to peripheral circulation, compared to resuscitation with NS or HES.

Early changes of CD4＋CD25＋Foxp3＋ regulatory T cells and Th1/Th2, Tc1/Tc2 profiles in the peripheral blood of rats with controlled hemorrhagic shock and no fluid resuscitation

Background Hemorrhagic shock induces immune dysfunction. Regulatory T cells （Tregs）, T-helper （Th） cells, and cytotoxic T-lymphocytes （CTLs） can execute many crucial actions in immune and inflammatory responses. This study was conducted to investigate the early pathophysiological changes of CD4＋CD25＋Foxp3＋ Treg and Th1/Th2, Tc1/Tc2 profiles in the peripheral blood of rats with controlled hemorrhagic shock and no fluid resuscitation. Methods A rat model of controlled hemorrhagic shock with no fluid resuscitation was established. Peripheral blood samples were taken before and four hours after hemorrhagic shock with no fluid resuscitation. Three color flow cytometry was used to detect Tregs, Thl, Th2, Tcl and Tc2 ceils in the samples. Results In the peripheral blood of rats, the percentage of Tregs four hours after hemorrhagic shock was significantly lower than before hemorrhagic shock （P=0.001）. The ratios of Th1/Th2 and Tc1/Tc2 were changed from （23.08±8.98）% to （23.91±15.36）%, and from （40.40±21.56）% to （65.48±23.88）%, respectively. Conclusions At an early stage, the advent of hemorrhagic shock is related to an early decrease of Tregs, and a mild shift in the Th1/Th2, Tc1/Tc2 balance toward Thl and Tcl dominance. These changes are part of a hyper-inflammatory state of the host, and will deteriorate the maintenance of immune balance. Further influences and detailed mechanisms need to be investigated.

Effect of hypertonic saline resuscitation on heme oxygenase-1 mRNA expression and apoptosis of the intestinal mucosa in a rat model of hemorrhagic shock

Background Massive blood loss due to trauma is the leading cause of death in trauma patients and military combatants. The fluid category of resuscitation for hypotensive trauma patients is open to debate. This study was conducted to investigate the early effects of hypertonic and isotonic saline solutions on heme oxygenase-1 （HO-1） mRNA expression and apoptosis in the intestinal mucosa of rats with hemorrhagic shock. Methods A model of severe hemorrhagic shock was established in 21 Sprague-Dawley rats. The rats were randomly divided into sham, normal saline resuscitation （NS）, and hypertonic saline resuscitation （HTS） groups, with 7 in each group. We assessed and compared the HO-1 mRNA expression and apoptosis in the small intestinal mucosa of rats after hemorrhagic shock and resuscitation using the SYBR Green I fluorescence quantitative reverse transcriptase polymerase chain reaction, fluorescein-iso-thiocyanate-annexin V/propidium iodide double staining, and flow cytometry. Results In the early stage of hemorrhagic shock and resuscitation, marked apoptosis occurred in the small intestinal mucosa from both the NS and HTS groups. The apoptotic rate in the NS group was higher than that in the HTS group （P 〈0.01）. Among the three groups, HO-1 mRNA mucosa from the HTS group had the highest level of expression; however, the differences were not significant. There was a significant negative correlation between HO-1 mRNA expression and apoptosis in the small intestinal mucosa from the NS and HTS groups after hemorrhagic shock and resuscitation. Conclusions In this rat model of severe hemorrhagic shock, HTS resuscitation with a small volume is more effective than NS resuscitation in reducing apoptosis of the intestinal mucosa. Further, HO-1 mRNA over-expression in the intestinal mucosa may be one of the molecular mechanisms of HTS in the resuscitation of hemorrhagic shock.

A safety evaluation of profound hypothermia-induced suspended animation for delayed resuscitation at 90 or 120min

Background: The successful treatment of military combat casualties with penetrating injuries is significantly dependent on the time needed to get the patient to an adequate treatment facility. Profound hypothermia induced suspended animation for delayed resuscitation(SADR) is a novel approach for inducing cardiac arrest and buying additional time for such injuries. However, the time used to safely administer circulatory arrest(CA) is controversial. The goal of this study was to evaluate the safety of hypothermia-induced SADR over 90 and 120 min time intervals.Methods: Sixteen male BAMA minipigs were randomized into two groups: CA90 group(90 min, n =8) and CA120 group(120 min, n =8). Cannulation of the right common carotid arteries and internal jugular veins was performed to establish cardiopulmonary bypass for each animal. Through the perfusion of cold organ preservation solution(OPS), cardioplegia and profound hypothermia(15℃) were induced. After CA, cardiopumonary bypass(CPB) was restarted, and the animals were gradually re-warmed and resuscitated. The animals were assisted with ventilators until spontaneous breathing was achieved. The index of hemodynamic perioperative serum chemistry values [alanine transaminase(ALT), aspartate aminotransferase(AST), creatinine(CR), lactic dehydrogenase(LDH) and troponin T(TnT)] and survival were observed from pre-operation to 7 days post-operation.Results: Fifteen animals were enrolled in the experiment, while 1 animal in CA120 group died from surgical error. All 8 animals in CA90 group recovered, with only 1 animal displaying mild disability. However, in CA120 group, only 2 animals survived with severe disability, and the other 5 animals died after 2 days post-operation. In CA90 group, the perioperative serum chemistry values increased at 1 day post-operation(ALT 84.43±18.65 U/L; AST 88.99±23.19 U/L; Cr 87.90±24.49μmol/L; LDH 1894.13±322.26 U/L; TnT 0.849±0.135 ng/ml) but decreased to normal or almost normal levels at 7 days post-operation(ALT 52.48±9.04 U/L; AST 75.23±21.46 U/L; Cr 82.69±18.41μmol/L; LDH 944.67±834.32 U/L; TnT 0.336±0.076 ng/ml).Conclusion: Profound hypothermia-induced SADR is an effective method for inducing cardiac arrest. Our results indicate that inducing CA for 90 min(at 15℃) is safer than doing so for 120 min. Our results indicate that 120 min of CA at 15℃ is dangerous and can result in high mortality and severe neurological complications. Further experimentation is needed to determine whether 120 min of CA at temperatures lower than 15℃ can lead to safe recovery.

CB 1 cannabinoid receptor participates in the vascular hyporeactivity resulting from hemorrhagic shock in rats

Background Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabinoid receptor （CB1 R） was involved in the development of vascular hyporeactivity in rats suffering from hemorrhagic shock. Methods Sixteen animals were randomly divided into two groups （n=8 in each group）： sham-operated （Sham） and hemorrhagic shock （HS） groups. Hemorrhagic shock was induced by bleeding. The mean arterial pressure （MAP） was reduced to and stabilized at （25±5） mmHg for 2 hours. The vascular reactivity was determined by the response of MAP to norepinephrine （NE）. In later experiments another twelve animals were used in which the changes of CB1R mRNA and protein in aorta and superior mesenteric artery （SMA） were analyzed by RT-PCR and Western blotting. In addition, we investigated the effects of a CB1R antagonist on the vascular hyporeactivity and survival rates in rats with hemorrhagic shock. Survival rates were analyzed by the Fisher＇s exact probability test. The MAP response was analyzed by one-way analysis of variance （ANOVA）. Results Vascular hyporeactivity developed in all animals suffering from hemorrhagic shock. The expression of CBIR mRNA and protein in aorta and 2-3 branches of the SMA were significantly increased in the HS group after the development of vascular hyporeactivity when compared to those in Sham group. When SR141716A or AM251 was administered, the MAP response to NE was （41.75±4.08） mmHg or （44.78±1.80） mmHg respectively, which was higher than that in saline groups with （4.31±0.36） mmHg （P 〈0.01）. We also showed an increased 4-hour survival rate in the SR141716A or AM251-treated group with 20% or 30%, but with a statistically significant difference present between the AM251-treated and saline groups （P 〈0.05）. Conclusions CBIR is involved in vascular hyporeactivity resulting from hemorrhagic shock in rats, and CB1R antagonist may be useful in treating patients with traumatic, hemorrhagic shock who need field-rescue or initial treatment.