Oxygen therapy, cardiopulmonary resuscitation, euthanasia

Question 1

Oxygen delivery depends on?

Answer 1

• Hemoglobin concentration (Hb) –> Anemia
  
  • transport of O2 from lungs to tissue
• Oxygenisation of the arterial blood (PaO2) –> hypoxaemia
• Cardiac output –> Hemodynamic disturbance
  
  • ​e.g. hypovolaemia
• Hypoxia: PaO2 < 80 mmHg, Sa O2 <90%
• Goal: to increase the inspired O2 concentration (FiO2)
• FiO2 = fraction of inspired air

Question 2

Clinical signs of hypoxaemia

Answer 2

• restlessness (panic seen in the eyes,)
• dyspnoe
• increased respiratory rate ( > 32-40/min)
• labial breathing
• open mouth breathing (cats)
• abnormal respiratory sounds
  
  • upper airway stridor
  • crepitation
  • respiration 0 (pleural effusion, pneumothorax)
• Cyanosis
• gasping

Question 3

What do you do incase of hypoxaemia?

Answer 3

• Sedation is necessary! to decrease stress and calm down to decrease hyperventilation
• acepromazin
• butorphanol
• midazolam

Question 4

Common causes of Hypoxia:

Answer 4

• Upper respiratory obstruction
• Brachycephal syndrome - laryngeal collapse
• Laryngeal paralysis (large breed, old dogs)
• tracheal collapse (small toy breeds)
• Pulmonary diseases
• Pneumonia
• pulmonary edema/ARDS
• congestive heart failure (edema formation)
• pleural effusion
• thoracic trauma (pneumothorax, lung contusion)
• inhalation of toxic gases (smoke, CO)
• severe anemia

Question 5

Arterial blood gas analysis

• when is it used, what do you measure?

Answer 5

• to measure degree of hypoxia
• you can use femoral or metatarsal arteries
• You measure: PaO2, SatO2, PaCO2
• A-a gradient: difference between alveolar O2 pressure and PaO2 (<10-15)
• “rule of 120”: PaO2 + PaCO2, if <120 –> V/Q mismatch
• PaO2/FiO2 ratio
• normal: > 400. Hypoxaemia: 300-400
• acute lung injury: 200-300
• Acute respiratory distress syndrome < 200

Question 6

How much O2 do you give by “flow by”?

Answer 6

2-3 Liter/min –> FiO2: 25-40%

Question 7

How much oxygen do you give by Oxygen hood/collar?

Answer 7

1 Liter/10kg/min –> FiO2 40-60%

Question 8

How much oxygen do you give by nasal oxygen catheter?

Answer 8

50-100 ml/kg/min –> FiO2: 40-50%

Question 9

FiO2 value in Oxygen cage

Answer 9

30-50%

Question 10

FiO2 value in endtracheal tube

Answer 10

21-100%

Question 11

Indications of mechanical ventilation

Answer 11

• Severe hypoxia (PO2 < 60mmHg)
• severe hypercapnia (PCO2 > 60mmHg)
• excessive work of breathing

Question 12

Cardiopulmonary cerebral resuscitation (CPCR)

• Indications

Answer 12

• cardiorespiratory arrest (CPA)

Question 13

Cardiopulmonary cerebral resuscitation (CPCR)

• clinical signs

Answer 13

• gasping/agonia breathing pattern
• unconciousness
• lack of spontaneous breathing
• lack of palpable pulse
• lack of cardiac sounds
• Poor prognosis
• < 10% ROSC (resuscitate)
• < 1% survive to discharge

Question 14

Cardiopulmonary cerebral resuscitation (CPCR)

• Recover (steps)

Answer 14

1. Prepareness and prevention
2. Basic life support
3. Advanced life support
4. Monitoring
5. Post-resuscitation care

Question 15

Potentially reversible causes of CPA

Answer 15

• 5 “H”:
• hypovolaemia/haemorrhage
• hypoxia/hypoventilation
• hydrogen ions –> acidosis
• hyperkalaemia/hypokalaemia
• hypoglycaemia (very often in yorkshire due to parasiti inf.)
• 5 “T”:
• Toxins
• tension pneumothorax
• thromboembolism
• tamponade (periardial)
• trauma

Question 16

Cardiopulmonary cerebral resuscitation (CPCR)

• Common critical patients:

Answer 16

• SIRS (systemic inflammatory response syndrome)
• due to e.g IHA or pancreatitis
• septicaemia
• congestive heart failure (furosemide dose adjustment)
• severe respiratory disease, ARDS
• cerebral diseases (seizures)
• multiple trauma
• coagulopathy, toxicosis, anaesthesia
• ill puppies bodyweight < 2kg!

Question 17

Things to consider before CRCP

Answer 17

• underlying disease
• owners will (expensive)
• timing - within 3-5min after CPA
• equipment
• trained staff (3+n)

Question 18

The ABC of cardiopulmonary resuscitation

Answer 18

• BLS (Basic life support)
• Airways
• Breathing
• Circulation
• ALS
• Drugs
• ECG
• Fluids

Question 19

Basic Life Support (BLS)

Answer 19

• A: Airways
• clean the airways (mucous, FB)
• encotracheal tube
• B: breathing
• with AMBU-ballon 10-12/min rate
• Circulation:
• thoracic compressions
• right lateral recumbency
• position of the hands
  
  • medium large breed: both hands on the widest points of the thorax
  • medium breeds: one hand over the heart (4-6 intercostal space)
  • small breed and cats: 1 hand over the cardiac area, thumb on the other side of the chest.

Question 20

D: Drugs

Answer 20

• Drug application: IV, IM
• safe: atropin, epinephrine/adrenalin, lidokain, nloxon, vasopressin
• 2-2.5 x dose is necessary (epinephrine: 3-10 x IV dose)
• drug should be solved in 5-10 ml sterile water or saline
• CAVE: severe pulmonary disease (edema). (cave means avoid)
• Commonly used drugs:
• Adrenalin (tenogen inj)
  
  • mainly alpha2 adrenergic stimulatory effect: peripheral arteriolar vasoconstriction increase –> cerebral and coronarial perfusion pressure increases
  • 0,01 mg/kg IV
  • dosage can be repeated in 3-5min (max: 0.1mg/kg IV)
• Atropin
  
  • heart rate increase, vascular resistance increase, blood pressure increase
  • most effective in case of vagotonia induced asystole
  • 0.04 mg/kg IV
  • can be repeated in 3-5 min 3times

Question 21

E: ECG

Answer 21

• Background:
• asystole
• electric activity without pulse
• ventricular tachycardia
• ventricular fibrillation
• severe sinusbradycardia

Question 22

F: Fluid therapy

Answer 22

• Patients with hypovolaemia: shock dosis
• crystalloids: dog (90 ml/kg) cat (45 ml7kg)
• colloids (HAES): dog (5ml/kg) cat (2-3ml/kg)
• hypertonic saline: NaCl 3%
• patients with euvolemia: crystalloids in bolus with maximum speed
• • dog: 20 ml/kg bolus
• • Cat: 10 ml/kg bolus

Question 23

Reasons for euthanasia

Answer 23

• incurable disease or injury
• control of infectious diseases
• unavertable attack
• scientific research
• high treatment cost

Question 24

When to do euthanasia?

• quality of life measured by

Answer 24

• Pain (1-10)
• Appetite (1-10)
• Hydration (1-10)
• Hygine (1-10)
• mood (1-10)
• locomotion (1-10)
• more good than bad days (1-10)

> 35: acceptable QOL (quality of life)

Question 25

Performing euthanasia

• drugs

Answer 25

• general anesthesia
• Acepromazin/ketamin+diazepam/propofol, IV
• drugs for euthanasia
• pentobarbital 600-200 mg/ttkg
  
  • Release inj (1ml/5ttkg)
  • Euthasol 40% inj
• T-61 inj., 0.3 ml/ttkg (?)
• If IV catheterusation is not possible, induce anaesthesia IM and apply euthanaisia i.c
• monitor heart, respiration, cornea reflexes