After hemorrhagic shock treatment, clamp the jugular vein of the anesthetized rat. Remove the catheter from the veins. Upon ligation, ensure that there is no blood leakage from the vessels.
Now use a 5-0 sterile suture to close incised areas with subcutaneous and cutaneous stitches. Disinfect the surgical area with 10%povidone iodine solution. Using a one milliliter syringe fitted with a 26 gauge needle, subcutaneously inject buprenorphine.
Upon awakening, place the rat on the heating mat in its cage. After 16 hours of hemorrhagic shock induction, draw blood drop from the end of the tail to measure blood lactate. Place the anesthetized rat on the surgical table and insert the rectal probe.
For carotid artery cannulation, use DeBakey atraumatic forceps to grasp the skin and make an incision in the middle of the neck with fine and sharp scissors or a scalpel. With standard pattern forceps, gently dilacerate tissue. Separate the salivary glands and open the tracheal muscle to reveal the tracheal rings.
Isolate the left carotid artery from the nerve with standard pattern forceps and ligate it distally with a 4-0 silk thread. Now place the suture thread on the proximal side of the artery and prepare a surgeon's knot without closing it. After clamping, use Vannas micro dissecting scissors to incise the carotid artery.
With standard operating forceps, gently grasp the artery wall to enlarge the opening and cannulate the artery with the catheter provided, holding it using forceps. Gently unclamp the artery and ensure that the blood is not flowing back into the catheter. After confirming the correct blood pressure signal, advance the catheter slightly into the artery and tighten the previously prepared surgeon knot.
Basal mean arterial pressure was similar between sham and hemorrhagic shock groups 24 hours post-hemorrhagic shock induction. The mean arterial pressure significantly decreased in the hemorrhagic shock group due to a reduction in diastolic blood pressure. No changes were observed in systolic blood pressure, pulse pressure, and heart rate across groups.
While the shock index remained unchanged, the modified shock index exhibited a notable increase in the hemorrhagic shock group. Lactatemia, indicative of global metabolic impairment, showed a significant increase following hemorrhagic shock, further elevating after 16 hours of hemorrhagic shock. Temperature and respiration rate, markers of systemic inflammatory response syndrome remained unchanged between groups 16 hours after hemorrhagic shock induction.
Behavioral assessments demonstrated an increased behavioral score in the hemorrhagic shock group, suggesting altered postures and activities.
