Measurement of central venous pressure in anesthetized rabbits and rats

Summary

The experimental method was obtained from the official website of the Fourth Military Medical University

Operation method

Measurement of central venous pressure in anesthetized rabbits and rats

Principle

Central venous pressure (central venous pressure CVP) is an index used to reflect the pressure changes in the right atrium. The change of right atrial pressure is affected by two factors: the first is the situation of upper and lower vena cava reflux, for example, when there is a large amount of blood loss or loss of body fluids and hypovolemic shock occurs, the volume of return blood is significantly reduced, the right atrial pressure will be reduced, and the central venous pressure will be lowered; the second is the change of the right ventricular pressure, for example, when there is high pressure of pulmonary artery, the right ventricular pressure will be increased, and the right atrial blood will enter into right ventricle will be blocked, and the right atrial pressure will be increased, and the central venous pressure will be increased. The second is the change of pressure within the right ventricle, for example, in pulmonary hypertension, the pressure within the right ventricle also increases, and the blood in the right ventricle is blocked from entering the right ventricle.

Materials and Instruments

Rabbit Rat
Ethyl carbamate injection Pentobarbital sodium injection Procaine injection Heparin saline injection
Animal laboratory bench Plastic catheter Water pressure meter Pressure transducer Multi-channel physiological signal acquisition and recording equipment

Move

1. Preparation of experimental equipment and reagents

Rabbits, weighing about 2 k g; rats, weighing about 200-250 g. 20% urethane injection or 1.5% pentobarbital sodium injection, 1% procaine injection, 0.3% heparin saline injection, a set of commonly used experimental equipment, a laboratory table for rabbits or rats, plastic catheters for rabbits or rats (outer diameter of the catheters for rabbits is 2 mm, inner diameter is 1.5 mm; inner diameter of the catheters for rats is 1 mm, a soft plastic catheter), a water manometer or a pressure transducer, a water pressure meter or a pressure transducer, a water pressure meter or a pressure transducer. The inner diameter of the catheter for rabbits is 1.5 mm; the outer diameter of the catheter for rats is 1 mm and the inner diameter of the catheter is 0.8 mm, which is a relatively soft plastic catheter), a water manometer or a pressure transducer, and its multi-channel physiological signal acquisition and recording instruments.

2. Experimental Methods and ProceduresRabbits weighing about 2 k g were anesthetized with 20% urethane injection 5 ml/ k g or 1.5% pentobarbital sodium injection 2 ml/ kg by intravenous injection at the ear margin. After the animals were anesthetized, they were fixed on the experimental table, their necks were trimmed, and the skin in the middle of their necks was cut with surgical scissors, and the external jugular vein (which had two branches) was seen by bluntly separating the subcutaneous tissues on the right side with vascular forceps. The two branches were carefully separated with vascular forceps and fused together for about 2 cm. Two surgical wires were threaded through the distal and proximal ends of the vein, and the distal end was ligated first. The distal ligature was gently lifted up, and an incision was made with ophthalmic scissors at an angle of 45° on the vein wall, and the catheter of the saline-filled water manometer or the catheter of the pressure transducer was inserted for about 4 cm in the proximal direction. The vessel and catheter are then gently ligated with a surgical wire at the proximal end, and the catheter is secured with a surgical wire at the distal end. The fluctuation of the central venous pressure can be seen by turning on the three-way switch of the catheter or pressure transducer of the hydrometer.

Caveat

Because of the thin wall of the vein, it must be separated carefully and gently, bluntly with a glass parting needle, and the fascial tissue on the wall must be separated cleanly. When you cut the socket in the wall of the vein, the previously filled vein will immediately collapse and flatten, and the catheter can be easily inserted by lifting up the cut with a small ophthalmic forceps or a small pull hook curved with a needle when inserting the catheter.

For more product details, please visit Aladdin Scientific website.

https://www.aladdinsci.com/