Monitoring the Respiratory System: CAPNOGRAPH, SPO2, ETCO2, INCO2 PDF

MONITORING THE RESPIRATORY SYSTEM CO2 and SPO2  GOAL OF RESPIRATIONS Acidosis- A buildup of To work with cardiovascular acid in the blood stream. system to… CO2 is Acidic 1...

MONITORING THE RESPIRATORY SYSTEM CO2 and SPO2  GOAL OF RESPIRATIONS Acidosis- A buildup of To work with cardiovascular acid in the blood stream. system to… CO2 is Acidic 1. Bring oxygen to tissue to Inadequate oxygenation prevent hypoxemia of the tissues for longer than 4 minutes could 2. Remove CO2 from body to result in permanent brain damage prevent acidosis PULMONARY 3 FUNCTION REVIEW As air is inhaled it brings fresh oxygen O2 is exchanged for CO2 at a cellular level in the alveoli CO2 is removed from the body by exhalation O2 is carried through the blood to the rest of the body Remember that all blood passes through the heart before arriving in the lungs The cardiovascular system and the respiratory system work very closely together!  4 DIFFUSION The movement of particles from a high concentration to a lower concentration until equilibrium is reached.  NORMAL VALUES Normal Ranges for Respiratory Rate in Breath/Min Patient Breaths/min Cat or Small Dog 10-20 Medium or Large Dog 5-10 Where can we find respiratory rate? Observing thoracic movement Observing movement of the reservoir bag Ausculting with stethoscope or and esophageal stethoscope Observe the ETT steam up at each breath The CO2 monitor PIP AND PEEP 6 These values refer to pressures within the lungs when an animal breaths. They are important values when using mechanical ventilation. PIP- PEAK INSPIRATORY PEEP- POSITIVE END PRESSURE EXPIRATORY PRESSURE PIP is the highest pressure measured in the respiratory cycle. PEEP is used to keep a positive We like to see between 10-20 pressure within the lungs at the cmH2O for a peak inspiratory end of a full exhale. pressure (just like when we give a PEEP will be set at 2-5 cmH2O to manual breath) prevent alveoli from collapsing When using a ventilator, it is completely. paramount that we set the There is a natural value of 1-2 cm machine to deliver an appropriate H2O that prevents atelectasis – tidal volume, so the ml of air partial or complete collapse of pushed into patient does not lung. exceed 20cmH2O Prolonged high pressures can lead to asystole! THE CAPNOGRAPH The End Tidal Carbon Dioxide Monitor (ETCO2) is also known as a Capnograph The capnograph also measures Inspired CO2 (INCO2) It is an apparatus that is placed at the rostral end of the ETT  8 SIGNIFICANCE OF ETCO2 CO2 is more diffusible across the alveolar wall than oxygen, therefore it changes more readily with changing ventilation. That is why we monitor CO2 instead of O2. End-tidal CO2 is the CO2 that is measured in the exhaled gas at the end of a normal exhalation. CO2 is one of the most reliable of your monitors. When cardiac function stops so does the exchange of CO2 for O2 and you will see a dramatic drop in your etCO2. ET CO2 Values Hypocapnia < 35mmHg Normal 35-45 mmHg Hypercapnia > 45mmHg Hypocapnia is usually caused by hyperventilation and can cause respiratory alkalosis. Hypercapnia is usually caused by hypoventilation and can cause respiratory acidosis.  9 INCO2 Inspired CO2 is monitored so we know our patient is not rebreathing the exhaled CO2. If patient does, this could cause a rapid increase in ETCO2 values (hypercapnia  respiratory acidosis) What could cause an increase in INCO2? Old Sodasorb in rebreather Unidirectional valves not functioning properly Reservoir bag too small Normal INCO2 Values Any animal 1-2 mmHg (ideal is 0)  10 WHAT ELSE CAN AFFECT CO2? RESPIRATORY TIDAL VOLUME CARDIAC ANESTHESIA CAPNOGRAPH RATE OUTPUT MACHINE Has it been Unidirectional warmed up? Hyperventilation valves working? Any foreign Hypoventilation If impaired 02 on? Shallow breaths bodies preventing Apneustic enough, we could Breathing tubes with a low PIP accurate breathing see hypercapnia kinked? numbers? One bronchi Need to be zero- intubated? ed?  11 WAVEFORMS OF ETCO2 (CAPNOGRAPHY) Presentation title 12  13 CAPNOGRAPHY WAVEFORMS  14 PULSE OXIMETER  SPO2 Non- invasive measurement of the percentage of hemoglobin saturated with oxygen in arterial blood. Hemoglobin- the oxygen carrying component of red blood cells. SPO2 will eventually indicate hypoventilation- but ETCO2 is faster at identifying it. SPO2 is a monitor more useful for oxygenation and circulation, not ventilation. Normal Value of SPO2 while patient SPO2 gives us a waveform (plethograph) and a is on 100% Oxygen is >95% percentage value. Anatomical locations to place SPO2 monitor: Tongue Lip Vulva or Prepuce Toe Ear The area needs to be hairless, non- pigmented, and thin.  16 SPO2 ADVANTAGES DISADVANTAGES Circulation to the probe site must Easy to use be adequate to get a reading Non-invasive Affected by vasoconstriction. Counts pulse rate as well Can give false sense of security Provides info on both oxygenation regarding tissue oxygen delivery and circulation in anemic patients. If the patient is anemic (low blood volume =low hemoglobin concentration) the pulse oximeter will likely say there is enough oxygen to supply all the tissue- potentially false Patients on 100% oxygen can get a reading of 100% saturation even if ventilations are inadequate.  17 TROUBLESHOOTING SPO2 NO PLETHOGRAPH VALUES DON’T MAKE DESATURATION IN PATIENT SENSE BREATHING NORMALLY Check your patient’s Remove probe from