Respiratory Procedures | Unit 3 Exam Review

Unit 3a, 3b, 3c: Monitoring of Gas Exchange

What are the 5 levels of Hypoxemia

normal

mild

moderate

severe

refractory

what is the range for normal hypoxemia

80-100

what is the range for mild hypoxemia

60-79

what is the range for moderate hypoxemia

40-59

what is the range for severe hypoxemia

below 40

refractory hypoxemia

severe hypoxemia that is unresponsive to increased levels of O2

Dyspnea

difficulty of breathing

how does dyspnea affect work of breathing

by causing the patient to expend more energy inhaling and exhaling

Pulse oximetry

noninvasive monitoring technique performed at bedside

indications for pulse oximetry

it will always be indicated, to monitor the adequacy of arterial oxyhemoglobin saturation

To quantify the response of arterial oxyhemoglobin saturation to therapeutic intervention or to diagnostic procedures, such as bronchoscopy

To comply with mandated regulations or recommendations by authoritative groups

contradictions for pulse oximetry

the ongoing need for actual measurements of pH, PaCO2, total Hb,

abnormal hemoglobins may be a relative ___________

hazards for pulse oximetry

none really but can give false results and lead to inappropriate treatment of patients

What technique is used to measure blood hemoglobin saturations when using pulse oximetry

It combines principles of spectrophotometry with photoplethysmography. It uses light absorption patterns to indicate saturation levels of pulsed blood

What are some of the factors that affect the accuracy or precision of Pulse oximetry

Motion artifact

abnormal Hb

intravascular dyes

low perfusion states

thick nails

nail polish and artificial nails

skin pigmentation

What can cause a falsely high SpO2

CO poisoning and methemoglobinemia

how does a blender work

Air and O2 enter the blender and pass through dual pressure regulators that exactly match the two pressures

What are the types of oxygen analyzers

Polarographic clark electrodxe and Galvanic fuel cell

how do you calibrate a Polarographic clark electrodxe and Galvanic fuel cell

consists of a 2-point calibration, one point is set with a probe exposed to 100% O2 and the second probe is exposed to room air(21%)

how do you troubleshoot a Polarographic clark electrodxe and Galvanic fuel cell

could be caused by low batteries, sensor depletion, or an electronic failure

What degree of accuracy should you expect from a Polarographic clark electrodxe and Galvanic fuel cell

+ 2%

Transcutaneous monitoring Indications

the need to monitor continuously the adequacy of arterial oxygenation or ventilation in infants and children

To ensure newborn infants are not receiving more O2 than necessary

The need to quantify the real-time responses to diagnostic and therapeutic interventions, as evidenced by PtcO2 or PtcO2 values

Transcutaneous monitoring Contraindications

there are no absolute contraindications

In patients with poor skin integrity or adhesive allergy, alternative devices should be considered

Transcutaneous monitoring hazards

false-negative or false-positive results may lead to inappropriate treatment

Tissue injury may occur at measuring site

Slower initial response time than pulse oximetry

How does transcutaneous monitoring work

It arterializes the underlying blood by heating the skin which also increases the permeability of the skin to O2 and CO2, which enhances diffusion from the capillaries to the sensor

What is the temperature range for transcutaneous monitoring

42C

Where should a transcutaneous monitoring probe be placed

Abdomen

chest

lower back

somewhere on the truck or somewhere there is a lot of tissue

What kind of injury can occur with transcutaneous monitoring

tissue injuries: which include erythema, blisters, burns, and skin tears

why can tissue injuries occur with transcutaneous monitoring

if the heated skin electrodes are too hot

How do you prevent injury from transcutaneous monitoring

Careful monitoring of the sensor temperature and regularly rotating the sensor site

What can cause erroneous results with a TCM

Improper calibration

Capnometry

The measurement of CO2 in respiratory gases.

when is capnometry indicated

monitoring adequacy of ventilation, circulation, metabolism, improving patient safety, and prediction of clinical outcomes.

What should the PETCO2 reading be at the beginning of exhalation

near zero

What does the PETCO2 indicate if it is higher than zero at the beginning at exhalation

indicates a patient is most likely hypoventilating

What is a normal PETCO2 reading

35-43 mmHg

invasive monitoring

require insertion of the sensor or collection device into the body. Provides a more accurate data but carries a greater risk

non-invasive monitoring

means of gathering data externally

indications of obtaining an arterial blood gas

to evaluate ventilation, acid-base balance, oxygenation status, and oxygen carrying capacity of blood.

to assess the patients' response to therapy or diagnostic tests

to monitor the severity and progression of a documented disease process

Sudden unexplained dyspnea

Cyanosis

Abnormal breath sounds

Severe, unexplained tachypnea

Heavy use of accessory muscles

Changes in ventilator setting

Cardiopulmonary resuscitation (CPR)

New appearance of diffuse infiltrates on CXR

Sudden appearance or progression of cardiac arrhythmia

Acute hypotension

Acute deterioration in neurologic function

contraindications of obtaining an arterial blood gas

abnormal results of a modified Allen test

Arterial puncture should not be performed through a lesion or distal to a surgical shunt

Because of the need for monitoring the femoral puncture site for an extended period, Femoral punctures should not be performed outside the hospital

Coagulopathy or medium dose to high dose anticoagulation therapy

hazards of obtaining an arterial blood gas

arteriospasm

Hemorrhage

Air or clotted blood emboli

Trauma to the vessel

Anaphylaxis from local anesthetic

Arterial occlusion

Patient or sampler contamination

Vasovagal response

Hematoma

Pain

the proper procedure for disposing of a needle

Never Recap a used neddle without a safety device

Never Handle a used needle using both hands

Never Point a used needle toward any part of the body

Never Bend, break, or remove used needles from syringes by hand

And always dispose of used syringes, needles, and other sharp items in appropriate puncture-resistant sharps containers

what is required for proper documentation of a blood gas

Date, time, site of sampling

Patient's body temperature, position, activity level, and respiratory rate

FiO2 concentration, oxygen device, and all applicable ventilatory support settings

indications of a capillary blood gas

ABG is always indicated but arterial access is unavailable. noninvasive monitor readings. Assessment of initiation, administration, or change in therapy is indicated. A change in patient status is detected by history or physical assessment. Monitoring the severity and progression of a documented disease process is desirable

contraindications of a capillary blood gas

on patients less than 24 hours old. When there is a need for direct analysis of oxygenation. When there is a need for direct analysis of arterial blood. Peripheral vasoconstriction. Polycythemia. Hypotension

hazards of a capillary blood gas

contamination and infection to the patient. Inappropriate patient management may result from reliance on capillary PO2 value. Inadvertent puncture or incision and consequent infection. Tibial artery laceration. Burns. Hematoma. Bruising. Scarring. Bleeding

what electrode is used for analyzing the pH of a blood gas

measuring electrode and/or reference electrode

what electrode is used for analyzing the PCO2 of a blood gas

severinghaus electrode

what electrode is used for analyzing the PO2 of a blood gas

Clark polarographic electrode

Random error

Point of care testing

performing blood gas analysis from laboratory to a patients bedside

Point of care testing use

used increasingly in hospitals and physician offices. Used for blood chestry and hematology parameters

Point of care testing benefits

reduces turnaround time, thus should improve care and lower costs