Establishment method and application of mesenteric artery hemorrhagic shock animal model

Abstract

The invention provides an establishment method and application of a mesenteric artery hemorrhagic shock animal model, and the establishment method comprises the following steps: S1, anesthetizing an animal, performing superior mesenteric artery digital subtraction angiography, artificial pneumoperitoneum and laparoscopic surgery after anesthesia, and performing hemorrhagic operation on a target blood vessel; and S2, after the animal has hemorrhagic shock for 10-15 minutes, injecting 0.9% sodium chloride injection into the animal for fluid infusion so as to maintain the stability of the blood pressure and heart rate of the animal, thereby obtaining the animal model of the abdominal traumatic hemorrhagic shock. A pig is used as an animal for establishing a model, vital signs and hemodynamic indexes of the animal are monitored in real time, and an auxiliary judgment standard of mesenteric artery hemorrhagic shock and a judgment standard of shock correction are determined according to the change trend of the indexes. According to the method, the animal model of the abdominal traumatic hemorrhagic shock is established, various indexes of the animal are continuously recorded, the shock condition and the shock correction condition are more accurately judged, and the shocked wounded can be rescued in time.

Description

Technical Field

[0001] This invention relates to a method for applying an animal model, specifically a method for establishing and applying an animal model of mesenteric artery hemorrhagic shock. Background Technology

[0002] Based on the current status of research and treatment of abdominal combat trauma and hemorrhagic shock in China, mesenteric artery traumatic hemorrhage is a type of abdominal combat trauma that is difficult to control with compression, has a high incidence of hemorrhagic shock, and a high mortality rate. Studies have shown that patients with hemorrhagic shock who receive effective treatment within one hour of injury can reduce the mortality rate by more than 50%; for every 30 minutes of delayed treatment, the mortality rate increases by 30%. Timely assessment and correction of shock can reduce ischemic and hypoxic damage to vital organs such as the brain, kidneys, and liver, and reduce the incidence of sequelae (such as renal insufficiency and brain injury).

[0003] Existing animal models of hemorrhagic shock mostly use the carotid and femoral arteries as target vessels and induce shock by direct arterial bloodletting. This does not fully reflect the actual situation of hemorrhagic shock caused by massive abdominal trauma. Some scholars have conducted experiments to induce abdominal bleeding by surgically destroying the liver or spleen, which is relatively close to the actual situation. However, it is relatively complicated to implement and the amount and speed of bleeding are difficult to control.

[0004] Currently, hemorrhagic shock is diagnosed based on blood pressure, shock index, blood loss assessment, clinical manifestations, and laboratory tests. However, the parameters for hemorrhagic shock vary depending on the type of trauma. Therefore, in actual patient assessment and treatment, shock from abdominal combat trauma may be missed or misdiagnosed, delaying the best time for treatment. Summary of the Invention

[0005] One of the objectives of this invention is to provide a method for establishing an animal model of mesenteric artery hemorrhagic shock, in order to solve the problem that existing methods for establishing animal models do not conform to the actual injuries of abdominal combat trauma.

[0006] The second objective of this invention is to provide an animal model of mesenteric artery hemorrhagic shock for the auxiliary determination of mesenteric artery hemorrhagic shock, so as to assist in the determination of mesenteric artery hemorrhagic shock.

[0007] The third objective of this invention is to provide an animal model of mesenteric artery hemorrhagic shock for the purpose of determining shock correction criteria.

[0008] One of the objectives of this invention is achieved as follows:

[0009] A method for establishing an animal model of mesenteric artery hemorrhagic shock includes the following steps:

[0010] S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum and laparoscopy were performed to perform hemorrhagic manipulation on the target blood vessel.

[0011] S2. Ten to fifteen minutes after the onset of mesenteric artery hemorrhagic shock in animals, administer 0.9% sodium chloride injection to replenish fluids at a rate of ≤25 mL / kg to maintain stable blood pressure and heart rate, thus establishing an animal model of mesenteric artery hemorrhagic shock.

[0012] Furthermore, the target vessel is located at the distal end of the porcine ileocolic artery.

[0013] Furthermore, the invasive arterial blood pressure includes MAP and SBP;

[0014] The criteria for determining mesenteric artery hemorrhagic shock are as follows: when the mean arterial pressure (MAP) decreases by 45±5 mmHg, or the spontaneous blood pressure (SBP) decreases to below 50 mmHg, accompanied by an increase in heart rate, it is considered hemorrhagic shock.

[0015] The second objective of this invention is achieved as follows:

[0016] Application of a mesenteric artery hemorrhagic shock animal model in the auxiliary determination of mesenteric artery hemorrhagic shock: Establishing a mesenteric artery hemorrhagic shock animal model; Real-time monitoring of invasive arterial blood pressure, heart rate, and blood routine in animals; Determining auxiliary determination criteria for mesenteric artery hemorrhagic shock based on the changing trends of indicators in the mesenteric artery hemorrhagic shock animal model before and during shock;

[0017] The steps to establish an animal model of mesenteric artery hemorrhagic shock include:

[0018] S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum, and laparoscopy were performed to induce hemorrhagic manipulation of the target vessel; the invasive arterial blood pressure and heart rate of the animals were recorded.

[0019] S2. Ten to fifteen minutes after the animals develop hemorrhagic shock, they are injected with 0.9% sodium chloride solution to rehydrate them. The rehydration volume is ≤25 mL / kg to maintain the stability of the animals' blood pressure and heart rate, thus obtaining an animal model of mesenteric artery hemorrhagic shock.

[0020] Furthermore, the complete blood count includes RBC, Hb, HCT, PLT, and WBC;

[0021] The auxiliary criteria for diagnosing mesenteric artery hemorrhagic shock are as follows:

[0022] When MAP decreases by 45±5 mmHg, or SBP decreases to below 50 mmHg, it is accompanied by increased heart rate, decreased RBC and PLT, and increased HCT, Hb and WBC.

[0023] The third objective of this invention is achieved as follows:

[0024] Application of a mesenteric artery hemorrhagic shock animal model in the determination of shock correction: A mesenteric artery hemorrhagic shock animal model was established; shock was corrected; invasive arterial blood pressure, heart rate, blood routine and arterial blood gas were monitored in real time; and the determination criteria for the correction of mesenteric artery hemorrhagic shock were determined based on the changing trends of the indicators of the mesenteric artery hemorrhagic shock animal model before shock and after shock correction.

[0025] The steps to establish an animal model of mesenteric artery hemorrhagic shock include:

[0026] S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum and laparoscopy were performed to perform hemorrhagic manipulation on the target blood vessel.

[0027] S2. Ten to fifteen minutes after the animals develop hemorrhagic shock, they are injected with 0.9% sodium chloride solution to rehydrate them. The rehydration volume is ≤25 mL / kg to maintain the stability of the animals' blood pressure and heart rate, thus obtaining an animal model of mesenteric artery hemorrhagic shock.

[0028] Furthermore, the complete blood count includes RBC, Hb, HCT, PLT, and WBC; the arterial blood gas includes pH, PaO2, BE, and Lac.

[0029] The criteria for correcting mesenteric artery hemorrhagic shock are as follows:

[0030] SBP reaches 85 mmHg or higher, or MAP rises to 60 mmHg or higher, and follow-up angiography shows disappearance of bleeding signs, accompanied by slowed heart rate and decreased RBC, Hb, HCT, PLT, pH and PaO2, and increased WBC, BE and Lac.

[0031] In the battlefield, soldiers are more likely to be hit in the abdomen by weapons, easily causing mesenteric artery trauma. The animal model of mesenteric artery hemorrhagic shock established in this invention more closely resembles the actual situation of abdominal combat trauma hemorrhagic shock. Laparoscopic severing of the distal ileocolic artery, a branch of the superior mesenteric artery in pigs, can induce massive abdominal hemorrhage and hemorrhagic shock, creating an uncontrolled model of massive abdominal hemorrhage and hemorrhagic shock with a success rate of 75% (15 / 20). Pulsating arterial bleeding can be directly observed under the microscope, and the bleeding site can be confirmed by angiography. The model is more consistent with actual battlefield injuries, simple and easy to implement, with controllable results, high success rate, and reproducibility. It provides a reliable platform for research on the treatment and hemostasis techniques for abdominal combat trauma hemorrhagic shock. This modeling technology is unprecedented both domestically and internationally, possessing a certain degree of innovation and advancement, and has research and application value.

[0032] This invention utilizes angiography and interventional embolization to stop bleeding in ruptured abdominal organs. This allows for rapid diagnosis and assessment of the bleeding site and risk, initial damage control, and immediate hemostasis and shock correction. It also buys valuable time for surgical intervention. Due to its minimally invasive nature and rapid hemostasis, interventional embolization saves time for surgery, reduces the possibility of complications during evacuation, and improves the efficiency of on-site treatment. This invention records the indicators of animals with corrected shock before, during, and after shock, establishing criteria for correcting mesenteric artery hemorrhagic shock. This helps determine the effectiveness of treatment for mesenteric artery hemorrhagic shock and allows for timely optimization of treatment plans. In this experiment, interventional embolization of animals with massive mesenteric artery hemorrhage and shock under laparoscopy achieved rapid hemostasis and shock correction. The effective rate of interventional embolization hemostasis in this experiment was 80.0% (12 / 15).

[0033] This invention, validated through animal models, demonstrates that vascular interventional embolization for mesenteric artery traumatic hemorrhagic shock achieves good therapeutic results. It is characterized by minimal invasiveness, rapid hemostasis, and low risk, and holds promise for correcting shock, reducing mortality rates in such casualties, decreasing reliance on surgical hemostasis techniques, lowering anesthesia risks, and enabling treatment for patients unsuitable for surgery. This improves the effectiveness of battlefield medical care and, to a certain extent, validates the application value of interventional embolization technology in the treatment of abdominal combat trauma. It possesses certain advanced features and is repeatable. Researchers and medical personnel can utilize this model to further study the treatment techniques for mesenteric artery hemorrhagic shock. Attached Figure Description

[0034] Figure 1 This is a flowchart of the present invention.

[0035] Figure 2 The graphs show the changes in SBP, DBP, MAP, and HR in animals before, during, and after shock. Detailed Implementation

[0036] The invention will now be described in further detail with reference to the accompanying drawings.

[0037] like Figure 1 As shown, the present invention provides a method for establishing an animal model of mesenteric artery hemorrhagic shock, comprising the following steps:

[0038] S1. Select the location of the target blood vessel through preliminary experiments.

[0039] Three domestic pigs, aged 3-5 months (one male and two females), each weighing between 25-30 kg, were used. The model established using pigs and sheep more closely resembles the human model in terms of cardiovascular system and hemodynamic shock response.

[0040] After satisfactory anesthesia, the pig was placed in a supine position with its limbs restrained to the catheter bed. An electrocardiogram monitor was connected to monitor the electrocardiogram and blood oxygen saturation. The groin area was prepared, disinfected, and draped with a sterile drape. The bilateral femoral arteries were punctured using the Seldinger technique, and 4F or 5F radial artery catheter sheaths were inserted. The left catheter sheath was used to continuously monitor invasive arterial blood pressure and collect blood samples, while the right catheter sheath was used for angiography. If femoral artery puncture and catheterization failed after multiple attempts, femoral artery incision and catheterization were performed instead.

[0041] Heparin sodium 100 U / kg was administered systemically via a catheter sheath for heparinization. A 4F or 5F-Cobra angiography catheter was then inserted to the opening of the superior mesenteric artery. Iohexol was used as the contrast agent. The high-pressure injector was set to a flow rate of 5-8 mL / s, a total flow rate of 15-20 mL, a pressure of 200-300 Pa, and a delay of 1 second for digital subtraction angiography. To avoid artifacts and obtain high-quality images, mechanical ventilation could be temporarily stopped, causing a respiratory pause of several seconds. One observation port was opened 15-20 cm above the umbilicus, and two operating ports were established 15 cm to the left and right of the umbilicus using 5 mm and 10 mm diameter trocars, respectively. Artificial pneumoperitoneum was performed, with the pneumoperitoneum pressure controlled below 15 mmHg. A laparoscope was inserted to observe the abdominal cavity. Tissue forceps were used to locate the cecum and ileocecal fold. In pigs, the cecum is usually located in the left iliac region, and its position is relatively fixed and its shape is relatively easy to identify.

[0042] Multiple groups of mesenteric lymph nodes were visible within the ileocecal mesentery, surrounded by the ileocolic artery, a distal branch of the superior mesenteric artery. Using the ileocolic artery of the most distal group of mesenteric lymph nodes as a base point, two more target points were selected proximally at intervals of 5 cm and 10 cm, for a total of three target points including the base point. Using tissue scissors, the mesentery, lymph node tissue, and ileocolic artery were dissected layer by layer, and the target vessels were severed. Bleeding and shock were observed; pulsating arterial bleeding was visible under the microscope. Invasive arterial blood pressure, heart rate, and oxygen saturation were closely monitored. Invasive arterial blood pressure included arterial maximum blood pressure (MAP) and spontaneous blood pressure (SBP). Hemorrhagic shock occurred when MAP decreased to 45 ± 5 mmHg or SBP decreased to below 50 mmHg, accompanied by increased heart rate, cold extremities, and decreased urine output.

[0043] Digital subtraction angiography was performed again. If necessary, the angiography catheter or microcatheter could be further superselectively inserted into the ileocolonic artery for angiography to assess for hemorrhage signs, including at least one of the following: contrast agent extravasation, local concentration, and intestinal visualization near the target site. The process of massive intraperitoneal hemorrhage and hemorrhagic shock was observed and compared to identify the artery near the last group of lymph nodes, namely the terminal ileocolonic artery of the pig, as the target vessel.

[0044] As shown in Table 1, three domestic pigs had an average body weight of 27.9 kg, an average body temperature of 37.8℃, an average heart rate of 90.6 beats / min, an average blood pressure of 131 / 85 mmHg, and an average intraperitoneal hemorrhage of 480 mL. The average time from target vessel transection to shock onset was 328 s, approximately 5.46 min. Transection of the arteries at all three target points during laparoscopy could induce hemorrhagic shock. The two proximal target points experienced more severe bleeding and faster shock onset, but both showed rapid bradycardia after bleeding, and rapid fluid resuscitation was insufficient to maintain effective circulation, leading to intraoperative death. However, transection of the artery embedded in the last group of mesenteric lymph nodes resulted in hemorrhagic shock approximately 12 min later. The shock development was stable, and the pigs survived for more than 2 hours intraoperatively, meeting the experimental requirements. Therefore, the distal vessel of the ileocolic artery embedded in the last group of lymph nodes was initially selected as the target vessel.

[0045] Table 1: Comparison of general conditions, target blood vessel location, amount of intraperitoneal hemorrhage, and shock status of animals in the preliminary experiments (n=3)

[0046]

[0047] S2. Animal model preparation: Record the animal's body weight, non-invasive cuff blood pressure, invasive arterial blood pressure, blood oxygen saturation, urine output, body temperature, and heart rate.

[0048] Twenty domestic pigs were selected, aged 3-5 months, with 10 males and 10 females, and all weighing between 25-30 kg. They were numbered according to the experimental order.

[0049] Record urine output via percutaneous bladder catheterization and drainage.

[0050] As shown in Table 2, the average body weight of the 20 domestic pigs was 27.6±1.67 kg. The physiological indicators were as follows: body surface temperature (T) was 37.7±0.63℃, pulse (P) was 104.6±7.96 beats / min, average non-invasive cuff blood pressure was approximately SBP 136±12.6 / DBP 85.8±9.9 mmHg, and blood oxygen saturation (SaO2) was in the range of 96%-100%. Their general condition (i.e., body weight) was comparable to the various physiological indicators.

[0051] Table 2: Comparison of general conditions and baseline physiological indicators of domestic pigs in the formal experiment (n=20)

[0052]

[0053]

[0054] Among them, the T-values ​​for independent samples of domestic pigs of different sexes are as follows: * indicates P<0.05; ** indicates P<0.01; *** indicates P<0.001.

[0055] This invention uses SPSS 27.0 statistical software for data statistical analysis and processing. Quantitative data conforming to or approximately normally distributed are expressed as mean ± standard deviation. The results indicate that the t-test and ANOVA were used for comparisons between groups, and P < 0.05 was considered statistically significant.

[0056] S3. Based on the location of the target blood vessel, perform hemorrhagic procedures on the pigs to maintain the blood pressure and heart rate of the pigs in hemorrhagic shock, and record the success rate of the laparoscopic technique, invasive arterial blood pressure, and urine output.

[0057] Twenty selected domestic pigs were anesthetized. After satisfactory anesthesia, the same digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum, and laparoscopy as in the above-mentioned pre-experiment were performed. Tissue forceps were used to locate the last group of lymph nodes in the ileocecal mesentery and cut the target vessels corresponding to the last group of lymph nodes. After bleeding, the invasive arterial blood pressure was closely monitored.

[0058] The mesenteric artery was pneumoperitoneum and laparoscopically operated on. The target vessel was located and cut endoscopically (i.e., a blood loss procedure). Pulsating arterial bleeding was observed endoscopically. The laparoscopic procedure was considered successful upon completion. Percutaneous bladder catheterization was performed to monitor changes in urine output.

[0059] This invention successfully performed laparoscopic surgery and severed the distal ileocolic artery in 16 cases, with a technical success rate of 80% (16 / 20).

[0060] S4. Continuously record the animal's systolic blood pressure, invasive arterial blood pressure, urine output, and body temperature; record animals that develop hemorrhagic shock, and administer 0.9% sodium chloride injection for rehydration 10-15 minutes after the onset of hemorrhagic shock.

[0061] When domestic pigs exhibit hemorrhagic shock, it is considered a successful animal model of hemorrhagic shock. Invasive arterial blood pressure is observed in domestic pigs. Hemorrhagic shock is diagnosed when the arterial blood pressure (MAP) drops to 45±5 mmHg, or the systolic blood pressure (SBP) drops below 50 mmHg, accompanied by increased heart rate, decreased extremity skin temperature (i.e., body temperature), and decreased urine output.

[0062] This invention successfully modeled hemorrhagic shock due to mesenteric artery trauma in 15 animals under laparoscopic guidance, with a success rate of 75% (15 / 20). Modeling failed in 5 domestic pigs, numbered 1, 3, 4, 5, and 8. Among them, one animal had successful laparoscopic technique but did not actually experience shock. The other 4 animals died during the operation. The modeling failures in the first 3 animals were considered to be due to lack of proficiency in anesthesia techniques, poor anticoagulation effect, and lack of proficiency in laparoscopic operation. The modeling failure in the last animal was considered to be due to the target vessel being located too close to the heart, resulting in excessive and rapid bleeding, which led to intraoperative death.

[0063] Following shock, the pigs experienced decreased urine output, with all exhibiting oliguria or anuria. Peritoneal blood collected via laparoscopy was calculated to have an average hemorrhage volume of 351.2 mL ± 45.3 mL across the 15 animals.

[0064] To maintain blood pressure and keep heart rate stable, administer sodium chloride to animals experiencing hemorrhagic shock, with a fluid resuscitation volume ≤25 mL / kg.

[0065] When digital subtraction angiography is performed again on animals that have experienced hemorrhagic shock, contrast agent concentration, contrast agent extravasation, or localized intestinal visualization may occur.

[0066] S5. Perform interventional embolization on animals that have developed hemorrhagic shock; determine the efficacy of interventional embolization for hemostasis, and record the effectiveness rate of interventional embolization for hemostasis and the survival rate of the animals.

[0067] After successfully establishing the shock model, observe the animal for 20-30 minutes. Then, use autologous skin or coils as embolizing agents to perform interventional embolization on the animal that has developed hemorrhagic shock, i.e., to correct the shock.

[0068] Blood was collected from the abdominal cavity by negative pressure suction inserted through a laparoscopic puncture port, and digital subtraction angiography was performed again on the animal that underwent interventional embolization.

[0069] The patient was observed for 20-30 minutes after the interventional embolization procedure to determine the efficacy. Specifically, the method for determining efficacy was as follows: After 20 minutes of observation following the interventional embolization procedure, if the invasive arterial blood pressure gradually recovered, with SBP reaching 85 mmHg or higher, or MAP rising to 60 mmHg or higher, and follow-up angiography showed disappearance of bleeding signs, accompanied by a decrease in heart rate and warming of the extremities, and the patient survived naturally for more than 24 hours post-procedure, the interventional embolization was considered effective in stopping the bleeding; otherwise, it was considered ineffective.

[0070] Blood samples were collected at three time points: before shock, during shock, and 10 minutes after interventional embolization, to test complete blood count and arterial blood gas.

[0071] Of the three animals whose hemostasis was unsuccessful by interventional embolization, two died during the procedure, and the other died 24 hours after undergoing surgical hemostasis.

[0072] Animals in shock that survive naturally for more than 24 hours after interventional embolization or combined hemostasis are considered to be alive.

[0073] Two cases of failed femoral artery puncture were converted to femoral artery incision and catheterization, and one case of incomplete interventional embolization was not completed. The success rate of interventional embolization was 80% (12 / 15). A total of 14 animals survived naturally for more than 24 hours, with a survival rate of 70% (14 / 20).

[0074] SBP, DBP, MAP, and heart rate (HR) were collected at three time points: before shock (T1), during shock (T2), and 10 minutes after interventional embolization (T3).

[0075] Table 3: Changes in SBP, DBP, MAP, and HR in animals

[0076]

[0077] As shown in Table 3 and Figure 2 As shown, within 10 minutes of severing the distal ileocolonic artery in domestic pigs, the invasive arterial blood pressure experienced a sustained and rapid decline, with SBP showing the most sensitive and fluctuating decrease. The lowest observed SBP value was 28 mmHg. MAP decreased relatively slowly, heart rate increased significantly, body temperature gradually decreased, and symptoms such as pale skin, slight cyanosis of the lips and abdomen, and cool extremities appeared, eventually leading to shock. During the shock phase, blood pressure plateaued at a low level, while the heart rate remained relatively high. After interventional embolization, blood pressure could rapidly recover, with SBP showing the most sensitive increase, before entering a plateau phase again. The heart rate could then slowly decrease, body temperature gradually recovered, pale skin improved, and cyanosis of the lips and abdomen gradually disappeared. Figure 2SBP, DBP, MAP, and HR are indicators before shock; SBP2, DBP2, MAP2, and HR2 are indicators during the shock period; and SBP3, DBP3, MAP3, and HR3 are indicators after interventional embolization.

[0078] S7. Compare the changes in test indicators in animals.

[0079] Whole blood samples were collected at three time points: before shock (T1), during shock (T2), and 10 minutes after interventional embolization (T3) for complete blood count and arterial blood gas analysis and comparison.

[0080] As shown in Table 4, the average blood routine test results of the 13 surviving domestic pigs of this invention were as follows: Red blood cell count (RBC) was 5.66 ± 0.88 × 10⁻⁶. 12 / L, hematocrit (HCT) was 0.296±0.046, hemoglobin (Hb) was 92.5±15.1 g / L, and white blood cell count (WBC) was 12.0±4.0×10 9 The platelet count (PLT) was 425.8 ± 110.0, and all preoperative indicators were within the normal range. Before shock and after interventional embolization, the experimental animals showed a significant decrease in both RBC and Hb, with the RBC count dropping as low as 2.99 × 10⁹ / L. 12 / L, Hb dropped to a minimum of 45 g / L, the difference was statistically significant (P < 0.01); before shock and after interventional embolization, HCT and PLT decreased significantly, while WBC increased significantly, reaching a maximum of 27.2 × 10 / L. 9 / L, the difference was statistically significant (P<0.05). From the pre-shock to the shock period, RBC and PLT decreased, while HCT, Hb and WBC increased.

[0081] Table 4: Comparison of Blood Routine Test Results in Laboratory Animals

[0082]

[0083] As shown in Table 5, the average values ​​of arterial blood gas analysis results for 13 domestic pigs in this invention are as follows: pH value 7.48±0.10, arterial blood oxygen partial pressure (PaO2) 96.00±12.02 mmHg, arterial blood carbon dioxide partial pressure (PaCO2) 36.22±10.08 mmHg, and actual bicarbonate (HCO3) ions 0.5%. -The levels of phospholipase (P) were 24.95±3.45 mmol / L, base excess (BE) was 0.15±2.67 mmol / L, and lactate (Lac) was 1.16±0.44 mmol / L. All these indicators were within the normal range before shock. Before shock and after interventional embolization, pH and PaO2 decreased, with pH dropping to a minimum of 7.25, a statistically significant difference (P<0.001). Conversely, BE and Lac increased before shock and after interventional embolization, a statistically significant difference (P<0.05).

[0084] Table 5: Comparison of arterial blood gas results in experimental animals before and after shock

[0085]

[0086]

[0087] Arterial blood gas analysis is an important clinical diagnostic tool, primarily used to assess respiratory function and acid-base balance. Arterial phase blood gas analysis is used to determine the presence of hypoxemia and hypercapnia, aiding in the diagnosis of respiratory failure. For example, type I respiratory failure is characterized by PaO2 < 60 mmHg and normal or decreased PaCO2; type II respiratory failure is characterized by PaO2 < 60 mmHg and PaCO2 > 50 mmHg. Shock is a severe circulatory disorder leading to insufficient tissue perfusion and reduced oxygen supply. In shock, arterial blood gas analysis typically reveals a series of changes reflecting the body's oxygenation, ventilation, and acid-base balance.

[0088] When lung oxygenation is impaired, ventilation / perfusion ratio is mismatched, or the concentration of inhaled oxygen is insufficient, hypoxemia can occur. PaO2 is usually below the normal range (<80 mmHg), and in severe cases, it may be below 60 mmHg, indicating hypoxemia. At this time, patients may exhibit hypoxic symptoms such as cyanosis, rapid breathing, and restlessness. When ventilation is insufficient or a compensatory mechanism exists, hypercapnia can occur. The compensatory mechanism, that is, in the case of hypoxemia, the body may compensate by increasing ventilation. However, if shock is severe, this compensatory mechanism may not be able to maintain itself, ultimately leading to an increase in PaCO2. In hypercapnia, PaCO2 is usually above the normal range (>45 mmHg). Patients may exhibit shallow and rapid breathing, confusion, and drowsiness, and in severe cases, respiratory acidosis. Arterial blood gas analysis can also determine acid-base imbalance, including metabolic acidosis and respiratory alkalosis. When pH < 7.35, HCO3- -Metabolic acidosis may occur when the pH level rises compensatorily but is insufficient to completely correct the pH. Respiratory alkalosis may occur when PaCO2 < 35 mmHg and pH > 7.45. In arterial blood gas analysis, the pH may be within the normal range (7.35-7.45), but PaCO2 and HCO3 may be elevated. - The opposite direction of change can lead to mixed acid-base imbalances. For example, an increase in PaCO2 (respiratory acidosis) while HCO3 increases... - Elevated (metabolic alkalosis).

[0089] This invention relates to the application of mesenteric artery hemorrhagic shock in the auxiliary assessment of mesenteric artery hemorrhagic shock in animals. It involves real-time monitoring of the animal's invasive arterial blood pressure, heart rate, limb skin temperature, urine output, and complete blood count. The changes in invasive arterial blood pressure (MAP or SBP), heart rate, limb skin temperature, urine output, RBC, Hb, HCT, PLT, and WBC before and during shock are used as auxiliary indicators for assessing mesenteric artery hemorrhagic shock, thus more accurately determining the state or severity of the shock.

[0090] The auxiliary criteria for diagnosing mesenteric artery hemorrhagic shock are: when MAP decreases to 45±5 mmHg, or SBP decreases to below 50 mmHg, accompanied by increased heart rate, decreased RBC and PLT, and increased HCT, Hb, and WBC.

[0091] This invention relates to the application of mesenteric artery hemorrhagic shock in the determination of shock correction in animals. It monitors the changes in invasive arterial blood pressure, heart rate, blood routine and arterial blood gas in animals in real time before and after shock correction. The determination criteria for the correction of mesenteric artery hemorrhagic shock are: SBP reaches 85 mmHg or above, or MAP increases to 60 mmHg or above, and the hemorrhage signs disappear on follow-up angiography, accompanied by slowed heart rate and decreased RBC, Hb, HCT, PLT, pH and PaO2, and increased WBC, BE and Lac.

[0092] Vascular interventional embolization technology has been widely used in the clinical treatment of various massive hemorrhages. Compared with traditional surgical hemostasis, endovascular intervention is less invasive, has a faster recovery, and is more effective, but it is also affected and limited by some factors. Although surgical procedures have a wider range of indications and are more mature, they are more invasive, have limited anesthesia, and are restricted in certain specific lesions. Combining surgical and interventional techniques can leverage the strengths of both and is an important supplement to traditional surgery. Introducing vascular interventional embolization technology into the emergency treatment system for traumatic massive hemorrhage can better treat the wounded.

[0093] The changes in various indicators of the experimental animals after successful vascular interventional embolization verified the effectiveness of the above-mentioned auxiliary judgment indicators.

[0094] The animal model of mesenteric artery traumatic hemorrhagic shock established by this invention has scientific research and military medical application value. This invention can be used to further study hemostasis and treatment techniques for this type of injury. Interventional embolization technology is used in the treatment of mesenteric artery trauma in combat, which is a supplement to surgical hemostasis and treatment techniques and will play a certain role in the treatment of such combat trauma in future battlefields.

Claims

1. A method for establishing an animal model of mesenteric artery hemorrhagic shock, characterized in that, Includes the following steps: S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum, and laparoscopy were performed to induce hemorrhagic manipulation of the target vessel; the invasive arterial blood pressure and heart rate of the animals were recorded. S2. Ten to fifteen minutes after the onset of mesenteric artery hemorrhagic shock in animals, administer 0.9% sodium chloride injection to replenish fluids at a rate of ≤25 mL / kg to maintain stable blood pressure and heart rate, thus establishing an animal model of mesenteric artery hemorrhagic shock.

2. The method for establishing an animal model of mesenteric artery hemorrhagic shock according to claim 1, characterized in that, The target vessel is located in the distal segment of the porcine ileocolic artery.

3. The method for establishing an animal model of mesenteric artery hemorrhagic shock according to claim 1, characterized in that, The invasive arterial blood pressure includes MAP and SBP; The criteria for determining mesenteric artery hemorrhagic shock are as follows: when the mean arterial pressure (MAP) decreases by 45±5 mmHg, or the spontaneous blood pressure (SBP) decreases to below 50 mmHg, accompanied by an increase in heart rate, it is considered hemorrhagic shock.

4. The application of an animal model of mesenteric artery hemorrhagic shock in the auxiliary determination of mesenteric artery hemorrhagic shock, characterized in that, Establish an animal model of mesenteric artery hemorrhagic shock; monitor invasive arterial blood pressure, heart rate and blood routine in animals in real time; determine auxiliary criteria for the diagnosis of mesenteric artery hemorrhagic shock based on the changing trends of the indicators in the animal model before and during shock. The steps to establish an animal model of mesenteric artery hemorrhagic shock include: S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum and laparoscopy were performed to perform hemorrhagic manipulation on the target blood vessel. S2. Ten to fifteen minutes after the animals develop hemorrhagic shock, they are injected with 0.9% sodium chloride solution to rehydrate them. The rehydration volume is ≤25 mL / kg to maintain the stability of the animals' blood pressure and heart rate, thus obtaining an animal model of mesenteric artery hemorrhagic shock.

5. The application of the animal model of mesenteric artery hemorrhagic shock according to claim 4 in the auxiliary determination of mesenteric artery hemorrhagic shock, characterized in that, The complete blood count includes RBC, Hb, HCT, PLT, and WBC. The auxiliary criteria for diagnosing mesenteric artery hemorrhagic shock are as follows: When MAP decreases to 45±5 mmHg, or SBP decreases to below 50 mmHg, it is accompanied by increased heart rate, decreased RBC and PLT, and increased HCT, Hb and WBC.

6. The application of an animal model of mesenteric artery hemorrhagic shock in the assessment of shock correction, characterized in that, Establish an animal model of mesenteric artery hemorrhagic shock; correct the shock; monitor the animals' invasive arterial blood pressure, heart rate, blood routine and arterial blood gas in real time; determine the criteria for correction of mesenteric artery hemorrhagic shock based on the changing trends of the indicators of the animal model of mesenteric artery hemorrhagic shock before shock and after shock correction. The steps to establish an animal model of mesenteric artery hemorrhagic shock include: S1. Using pigs as the animal model, the animals were anesthetized, and after anesthesia, digital subtraction angiography of the superior mesenteric artery, artificial pneumoperitoneum and laparoscopy were performed to perform hemorrhagic manipulation on the target blood vessel. S2. Ten to fifteen minutes after the animals develop hemorrhagic shock, they are injected with 0.9% sodium chloride solution to rehydrate them. The rehydration volume is ≤25 mL / kg to maintain the stability of the animals' blood pressure and heart rate, thus obtaining an animal model of mesenteric artery hemorrhagic shock.

7. The application of the mesenteric artery hemorrhagic shock animal model according to claim 6 in the determination of shock correction, characterized in that, The complete blood count includes RBC, Hb, HCT, PLT, and WBC; the arterial blood gas includes pH, PaO2, BE, and Lac. The criteria for correcting mesenteric artery hemorrhagic shock are as follows: SBP reaches 85 mmHg or higher, or MAP rises to 60 mmHg or higher, and follow-up angiography shows disappearance of bleeding signs, accompanied by slowed heart rate and decreased RBC, Hb, HCT, PLT, pH and PaO2, and increased WBC, BE and Lac.

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