Experiment ,patholophysiology of Pulmonary on rabbit Pathophysiology（病理生理学） Pathology uploaded by prabesh 杰诗

1. Experimental Pulmonary
Edema in Rabbits
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2. GoalsGoals
1. Replicate the animal model of
experimental pulmonary edema.
2. Understand the manifestations
and mechanisms of pulmonary
edema.
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3. ① Capillary hydrostatic pressure (17 mmHg)
② Interstitial hydrostatic pressure (-6.5 mmHg)
③ Plasma colloidal osmotic pressure (28 mmHg)
④ Interstitial colloidal osmotic pressure (5 mmHg)
The normal interchange of body fluid
between plasma and interstitial fluid
(17 - (-6.5)) - (28 - 5) = 0.5 mmHg
①
②
③
④
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4. Accumulation of excessive fluid in the
interstitium or alveoli of the lungs.
Pulmonary Edema
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5. Gross view
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Pulmonary Edema
Microscopic view
Normal
Edema

6. Rapid infusion of large amount of fluid
Effect of epinephrine
Mechanisms of Pulmonary Edema
in This Experiment
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7.  Animals: Rabbits
 Drugs:
Normal saline
Procaine (1%)
Epinephrine (1 mg/ml)
 Supplies:
Trachea cannula, venous catheter, intravenous
infusion device, surgical instruments, balances,
stethoscope, fixing table, syringes, suture,
gauze, filter paper, beaker
Lab Supplies
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8. Normal saline + Epinephrine
4 animals
Normal saline
2 animals
Groups
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9. 1. Weigh the rabbit; Fix the rabbit on the
fixing table;
- fix the limbs;
- fix the front tooth to the table;
Procedure
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10. 2. Cut the hair in the center of the neck;
3. Inject procaine (1%) (locally under the skin, 2-
3 ml/animal) for anesthesia;
4. Cut a 5-7cm excision on the center of the neck
(from the edge of thyroid cartilage to sternum) .
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11. 5. Dissect the trachea and the jugular vein;
6. Apply one suture under the trachea and two
sutures under the vein;
7. Cut an inverted “T”-shape excision 3-4 cartilage
rings below the thyroid cartilage;
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8. Insert the trachea cannula and ligate.

12. 9. Connect the venous catheter to the infusion
device, put in NS (500 ml) and remove the air in
the tubing;
10. Ligate the vein at the distal end;

13. 11. Cut a 45 º
“V”-shape opening;
• Insert the venous catheter and ligate at the
proximal end;
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14. 12. Slowly start infusion
of normal saline, 5-10
drops/min;
• Observe the respiratory
frequency and listen to
the breathing sound of
the lungs using
stethoscope;
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生
理
水
盐

15. 13. Quickly infuse normal
saline, 150-180
drops/min;
14. After infusion for 2/3
of the total volume,
add Epinephrine (0.5
mg/kg) (NS + EP
group);
(no Epinephrine added
to the NS only group).
Continue infusion at a lower
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2
3
EP

16. 15. Watch if there is any change in respiration,
listen to the appearance of moist rales of the
lungs; and watch if there is any pink frothy fluid
coming out;
16. When the frothy fluid appears, clamp the
trachea immediately using the forceps
- to avoid the leakage of the edema fluid;
- to let the animal die;
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17. 17. Open the chest and ligate at the branching of
the bronchus;
• Cut the trachea between the forceps and the
suture and take out the whole lungs;
• Do not damage the pleura;
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18. 18. Wipe off the moist on the surface of the lungs
using filter paper and weigh the lungs, and
calculate the lung ratio:
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Lung ratio =
Lung
weight （ g ）
Body weight （ kg ）
（ Normal value ： 4 ～
5 ）
19. Watch the gross changes of the lungs (volume,
surface, edge, color, texture, etc) ;
• Cut open the lungs and note the existence of
frothy fluid.

19.  Dissect using the glass hook or forceps (not the
scissors);
 Firmly fix the trachea cannula and the venous catheter
(notice the orientation of the insertion);
 Remove the air in the infusion device;
 Do not infuse too fast or too slow (150-180 drops/min)
for edema induction;
 Remove the lungs completely together with the trachea;
 Care should be taken in order not to damage and press
the lungs to avoid the leakage of the edema fluid.
Points for Attention
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20. Observational
Index
Animal No.
1 2 3 4 5 6
Amplitude and
frequency of
breathing
Cyanosis
Moist rales
Frothy fluid
Gross
changes
Color
Volume
Texture
Lung ratio
Results
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21. Lab Report Requirements
1. The name of the experiment, the experimenters,
the date.
2. The experimental purpose.
3. The experimental animal and its sex, weight and
health conditions.
4. Medicine and main equipment.
5. Main experimental methods and steps.
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22. 6. The result: the presentation generally can be in the
following two formats:
(1)Descriptive type:
Description in words.
(2) Chart type:
A table or diagram giving more clear reflection of
observation and comparison.
In order to make experimental results more clear and
comprehensive, the above two ways can be combined.
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23. 7. Discussion: By applying the theory of known
knowledge, explain the experimental phenomena
observed in the experiment, as well as the existing
problems and deficiency, and anomalies in the
experiment.
• Discussion should be based on the experimental
results.
8. Conclusion: according to the experimental purpose
and the results, summarize in general terms.
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