The approximate timing of classes

№	Steps of the class	Time (min)
1	Organizational part. Roll Call, reading the goals and objectives of the class, distribution of demonstration material	5
2	Discussion the questions 1-2	20
3	Watching videos, video-film, tasks №№ 1, 2	25
4	Break	10
5	Discussion the questions 3-6	35
6	Test	10
7	Summarizing the classroom work, assessment of competencies	5

Practical work of students

Task № 1.

Model an exogenous hypoxia and study its symptoms.

Technique. Take 3 mice, one of them place in a hermetically sealed balloon of Komovsky’s apparatus; the second mouse place in hermetically closed jar, the third mouse is the control. Mark an initial state of animals: behavior, character of breath, color of skin. Pump out air from the balloon, watching for level of barometric pressure on a manometer. Fix character and sequence of changes at the level of barometric pressure 0.8 atm., 0.6 atm., 0.4 atm., 0.2 atm.. Observe a clinical picture of acute hypoxia, mark character of breath. The received data write down to the protocol, analyze them. Conclude.

The Protocol of experiment

animal	Type of hypoxia	Color of skin	Character of breath	Pathogenesis of changes
The mouse 1	Exogenous hypobarbarometric
The mouse 2	Exogenous normobarbarometric
The mouse 3 (control)	-----------------

CONCLUSIONS:

Task № 2.

Cause blood type of hypoxia in mice: 1. poisoning by nitrates 2. poisoning by CO

Technique. Nitrates poisoning.

Inject subcutaneously 0,1 ml of 10 % sodium nitrate to a mouse. Observe a clinical picture of acute hypoxia. Pay attention to color of skin and mucous.

Carbom monoxide poisoning. (CO is received from the reaction of formic acid with H₂SO₄)

Place a mouse into jar connected with the help of a rubber tube with a source of CO. Research the behavior of an animal, color of skin and mucous.

Do the incision of dead animals. Compare color of skin, organs and blood. Fill in the summary protocol:

the protocol

Animal	Kind of influence	Color of skin	Color of blood	Pathogenesis of the changes
The mouse 1	Nitrate-poisoning
The mouse 2	CO-poisoning

CONCLUSIONS:

Task 3. Case study

Case 1

In the study of various aspects of pathogenesis of hypoxia and edema a laboratory rat was intravenously injected a high dose of adrenaline. Immediately after the injection paws and ears of the rat turned pale; arterial blood pressure increased from 120/70 mm Hg to 210/175 mm Hg; heart rate and respiration rate increased sharply. The level of P_a remained unchanged, but the levels of P_vand P_aCO₂ decreased. Nine minutes after the adrenaline injection when hyperventilation still persisted the rat developed acrocyanosis. The content of gases in the arterial blood remained normal, but a progressive decrease in the P_vO₂ level was noted. Four minutes later dyspnea developed, and moist rales appeared; the blood pressure decreased dramatically; the pulse pressure lowered, and heart beats became irregular. At the same time, P_aO₂ started to decrease, and P_aCO₂ increased. By the end of the 18th minute clonic and tonic seizures developed, agonal breathing (gasping) and foamy, reddish secretions from the respiratory tract appeared, and the rat died.

Questions:

1. Can we state that despite activation of the heart function, increased vascular tone, and high blood pressure the rat suffered from hypoxia immediately after the adrenaline injection? If you think so, substantiate your opinion. If you do not agree, name the time point by which hypoxia has developed.

2. What are the type(s) and pathogenesis of such hypoxia?

3. Did the rat develop edema? If you think so, name the organs where it occurred and the time point after the adrenaline infusion when the edema became evident?

4. If, in your opinion, edema developed in the rat, what forms of pathology in humans may lead to edema with similar localization?

case 2

An accident occurred in the aircraft during a flight on the height of 10,000 m. The cabin of the aircraft lost its hermetic state, and in the course of several seconds the barometric pressure inside fell down to atmospheric level at this altitude 170 mm Hg. The crew failed to make an urgent lowering maneuver, and the aircraft continued the flight at the same height for several minutes.

Questions:

1. What pathologic processes developed in the body of passengers during the aircraft accident? Which of them were the most dangerous for their well-being and can lead to death?

2. What are the likely causes and mechanisms of these pathologic processes?

3. What types of preexisting pathology could include the highest risk for life in this situation?

Case 3

A 30-year-old-woman has been brought to hospital by ambulance.

Her condition was serious. The preliminary diagnosis was "rupture of a uterine tube with internal bleeding due to ectopic pregnancy". On the way to hospital the patient lost consciousness several times. Examination in hospital showed that the patient was conscious, but confused. She was markedly pale, had a weak, rapid pulse; ausculation revealed muffled heart sounds; blood pressure 80/35 mm Hg. Examination showed the presence of varicous veins in the extremities. The patient told the physician that her condition worsened suddenly when she was removing hair on her legs with a depilator. Unexpectedly she felt short of breath, palpitations, pain in the heart. Later on in hospital, despite inhalation of oxygen, she went on complaining of shortness of breath.

Questions:

1. Which of the typical pathologic processes and what type of it could develop in the patient? Substantiate your answer.

2. Name the symptoms caused by this pathologic process. What are the mechanisms, underlying each of the symptoms?

3. Describe the causative factors of this pathologic process. Which of them are most likely to occur?

4. Why was the inhalation of oxygen ineffective to alleviate shortness of breath?

case 4

When a physician of the emergency service arrived at the site of a vehicle accident he found that the victim of the accident developed shock associated with an open fracture of the right leg and massive loss of blood. The patient also had a closed chest injury. When the bleeding was stopped by application of a tourniquet the physician injected to the patient subcutaneously appropriate doses of morphine (to alleviate pain) and a stimulant of the cardiac function. However, the treatment had no effect. The symptoms of shock continued to progress, the pulse was observed only in the large arteries (60 beats/min), blood pressure decreased up to 60/25 mm Hg. Auscultation revealed a depressed breathing over the left chest, and no breathing sounds over the right chest. Several minutes later breathing became shallow and ineffective; the patient started to "gasp air". With the aim to stimulate breathing the physician injected subcutaneously a stimulant of the respiratory center. However, this treatment also had no effect.

Questions:

1. What type (or types) of emergency state developed in the patient?

2. What types of hypoxia and in what sequence developed in the patient?

3. Describe the possible causes and pathogenesis of the given types of hypoxia. Explain the typical changes in pH, P_aCO₂, S_aO₂, S_vO₂, blood oxygen capacity, the minute volume of breathing, and the minute volume of circulation during these types of hypoxia.

4. Why was the treatment provided by the physician ineffective?

Case 5

A 30-year-old patient K. has been treated in the intensive care unit after a surgical procedure of uterus amputation which was done under an endotracheal ether narcosis. Suddenly the patient's condition worsened sharply. She developed a choking sensation, dyspnea, chills, psychomotor retardation and apathy. Her skin turned pale; acrocyanosis became evident. Physical examination showed an increased respiration rate of 28 per minute, muffled heart sounds, no rales during auscultation of the chest; the pulse was regular 120 beats/min; blood pressure 65/30 mm Hg; concentration of Hb 100 g/L; hematocrit 0.30 (N: 0.36-0.42). The patient was administered supplemental oxygen but these measures had no effect.

Questions:

1. What pathologic process(es) developed in the patient after the surgery? Substantiate your answer.

2. Can the worsening of the patient's condition be associated with the postsurgery development of hypoxia of:

a) respiratory type?

b) circulatory type?

c) anemic type?

d) cytotoxic type?

What are the possible causes and mechanisms of development of each of the presumed types of hypoxia in this case?

4. Are there any signs of the urgent adaptive mechanisms that could compensate hypoxia in this patient? Describe them, if they are present. Why do they appear to be ineffective in this case?

Case 6

A 50-year-old patient K. has undergone a gastrectomy under narcosis with the use of mechanical ventilation. The surgery was urgently performed due to extensive stomach bleeding which developed suddenly as a result of tumor decay. During the treatment of shock and during the surgery the patient was administered various volume expanders (approximately 1 L) and received a transfusion of 2.5 L of whole donor blood which had been stored for 2 days. By the 3-d day after the surgery, despite the restoration of the normal blood values of Hb, the patient complained of weakness, headache, dizziness. On examination: the skin of the extremities was cold; severe dyspnea and renal insufficiency were observed; in the conjunctiva a tint of jaundice appeared. Eventually, mechanical ventilation was initiated to treat the patient.

Questions:

1. What pathologic process(es) developed in the patient after the surgery? Substantiate your answer.

2. What are the possible causes and mechanisms of development of each of the pathologic processes:

a) before the surgery?

b) in the course of the surgery and immediately after its completion?

c) by the 3-d day after the surgery?

3. What adaptive processes could be activated in the patient as a result of hypoxia? Why were the adaptive processes ineffective in this case?

Case 7

A 60-year-old patient C. had an extensive transmural infarction in the anterior wall of the left ventricle 2 weeks before. During his stay in hospital he woke up at night with choking sensation and called for help. When a nurse came she helped the patient to sit up on the bed with his feet down on the floor. Then she opened the window. The patient felt a little better. However, 10 min later he began complaining of shortness of breath, the need coughing regularly (without secretions), and audible rales in the chest. The nurse gave the patient supplemental oxygen by face mask, and called a physician.

Questions:

1. What types of hypoxia did the patient suffer from? Substantiate your answer.

2. In what succession did these types of hypoxia develop in the patient?

3. How and why did the parameters of P_aO₂, P_aCO₂, P_vO₂, P_vCO₂, S_aCO₂, S_vO₂, pH change in the patient's blood? Substantiate your answer.

4. What are the possible mechanisms of immediate adaptation to hypoxia in the given patient?