Term
| Parameters representing the highest potential risk/benefit ratio for the typical ICU patient |
|
Definition
|
"Every test should be judged for usefullness where the best tests have little or no risk and high potential value. For example, a pulse Ox has good information with no known risk vs. a pulmonary artery catheter which has a high risk and other methods garner similar results"
|
|
|
Term
| Types of variabilities that can occur when monitoring a patient |
|
Definition
|
"Signals or Values are susceptible to variability due to artifacts, factitious events, physiologic variation, and instrument drift. Artifacts are spikes or shifts that are not consistent with pt status due to patient or monitoring lines being moved, or a patient cough; factitious events are real."
|
|
|
Term
| Parameters in determining tissue oxygenation |
|
Definition
|
"ABG analysis is best, but painful and has complications. Pulse oximetry is standard for continuous, noninvasive assessment of SaO2. it does not measure PaCO2"
|
|
|
Term
| Factors causing errors in SpO2 readings |
|
Definition
|
"motion artifacts (seizures, transport, shivering), intense daylight and flourescent, incandescent, xenon and infrared light sources, anemia and deeply pigmented skin, carboxyhemoglobin and methemoglobin, colors of nail polish, and blood-borne dyes"
|
|
|
Term
| Normal approximate value for oxygen consumption |
|
Definition
|
|
Term
| Effect of carbon monoxide on pulse oximeter readings |
|
Definition
|
Can produce falsely high saturation values
|
|
|
Term
| Percent of oxygen in the arterial blood normally extracted by the tissue |
|
Definition
|
|
Term
| Method used to measure oxygen consumption |
|
Definition
|
"Fick Method, and analysis of inspired and expired gases"
|
|
|
Term
| Normal range for P(A-a)O2 |
|
Definition
|
"5-15 mmHg, increases with age to approximately 10-20 mmHg in the elderly"
|
|
|
Term
| Estimate percentage shunt from P(A-a)O2 |
|
Definition
|
% shunt breathing 100%O2 = [P(A-a)O2]/20
|
|
|
Term
| Normal for the PaO2/Fio2 ratio |
|
Definition
|
|
Term
| Parameter considered most accurate and reliable measure of oxygenation efficiency |
|
Definition
|
Direct computation of the physiologic shunt (Qs/Qt)
|
|
|
Term
| Parameters used in calculating the Murray lung injury score |
|
Definition
|
"chest radiograph findings, PaO2/FIO2 ratio, positive end-expiratory pressure (PEEP) setting, and compliance. "
|
|
|
Term
| Best single measure of effective ventilation |
|
Definition
|
|
Term
| Best measure of the efficiency of gas exchange in the lung |
|
Definition
|
dead space/tidal volume ratio (Vd/Vt)
|
|
|
Term
| Normal and weaning range for VD/VT |
|
Definition
|
.20 to .40 - weaning range is .60
|
|
|
Term
| Disorders causing an increased VD/VT ratio |
|
Definition
|
"CHF, pulmonary embolism, ALI, or pulmonary hypertension, and in patients undergoing mechanical ventilation"
|
|
|
Term
| Normal disparity between end-tidal PCO2 (PETCO2) and PaCO2 |
|
Definition
|
"The PETCO2 normally is 1 to 5 mmHg less than the PaCO2, ranging between 35 and 43 mmHg. Because PETCO2 in healthy persons closely approximates the PaCO2, this measure is a potentially useful noninvasive index of the adequacy of ventilation"
|
|
|
Term
| "Conditions leading to an increased, and a decreased, end-tidal PCO2" |
|
Definition
|
"Increased - decreased effective ventilation, increased CO2 production: agitation, stress, shivering, fighting the vent, pain, anxiety, recovery from sedation or paralysis. Decreased - increased effective ventilation, marked decrease in effective ventilation, decreased CO2 production, decrease in lung perfusion(pulmonary embolus, decreased cardiac output)"
|
|
|
Term
| What is the value of the lower inflection point during measurement of the pressure-volume curve |
|
Definition
|
|
Term
| Use of P-V curves to determine the best tidal volumes and inspiratory pressures |
|
Definition
|
"A lung protective strategy of ventilating between the inflection an ddeflection points is considered beneficial, although there is no consensus in clinical practice on the best technique for measuring P-V curves or on their relevance to todal ventilation or to the selection of the level of PEEP"
|
|
|
Term
| Conditions associated with increased lung compliance measurement |
|
Definition
|
"Lung improvement in atelectasis, pneumonia, pulmonary edema, ALI/ARDS pneumothorax, fibrosis, bronchial intubation. Pulmonary emphysema, increased thoracic compliance from an improvement in obesity, ascites, chest wall deformity. Flail chest, position change - sit up"
|
|
|
Term
| Normal range for lung compliance |
|
Definition
|
|
Term
| Causes of increased airway resistance |
|
Definition
|
"small endotracheal tube, plug in endotracheal tube, biting on ET tube, increased bronchospasm, mucosal edema, increased secretions, increased airway obstruction, high gas flow rate"
|
|
|
Term
| Acceptable upper limit for peak airway and plateau pressures during mechanical ventilation |
|
Definition
|
no greater than 50 to 60 cm H2O for peak airway pressure; Plateau pressure should not exceed 30 to 35 cm H2O
|
|
|
Term
| Factors associated with an increased risk for auto-PEEP |
|
Definition
|
"expiratory muscle activity, pts received mech vent for obstructive airways, mechanically vented pts with high minute ventilation, patients with ARDS (due to high minute ventilation)"
|
|
|
Term
| Problems associated with auto-PEEP |
|
Definition
|
"erroneous calculation of static lung compliance, hemodynamic instability, barotrauma"
|
|
|
Term
| Normal range of oxygen consumption by the respiratory muscles (VO2R) |
|
Definition
|
2% - 5% of total oxygen consumption; increases up to 30% with hyperventilation
|
|
|
Term
| Breathing patterns suggesting respiratory muscle decompensation |
|
Definition
|
A very high and continuously increasing frequency (>30 breaths/min)
|
|
|
Term
| Parameters commonly used for bedside assessment of respiratory muscle strength |
|
Definition
|
|
Term
| Vital capacity value indicating significant muscle weakness |
|
Definition
|
VC less than 10 to 15 mL/kg
|
|
|
Term
| Parameter used to assess respiratory muscle endurance |
|
Definition
|
MVV (maximum voluntary ventilation)
|
|
|
Term
| Purposes of using ventilator graphics |
|
Definition
|
"They show many important patient-ventilator interactions such as presence of auto-PEEP, elevated airway pressure, presence of secretions, and the general pattern and dependability of supported ventilation"
|
|
|
Term
| Normal range for mean arterial pressure |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Normal mean pulmonary artery pressure |
|
Definition
|
|
Term
| Normal range for cardiac output |
|
Definition
|
|
Term
| Normal range for pulmonary capillary wedge pressure |
|
Definition
|
|
Term
|
Definition
|
"Right Ventricular Failure (myocardial infarction, cardiomyopathy); pulmonary valvular stenosis; tricuspid stenosis and regurgitation; pulmonary hypertension; pulmonary embolism; volume overload; compression around the ehart, constrictive pericarditis, cardiac tamponade; increased large-vessel tone throughout the body resulting in venoconstriction; arteriolar vasodilation, which increases the blood supply to the venous system; increased intrathoracid pressure (positive pressure breath or pneumothorax), placement of the transducer below the pt right atrial level; infusino of solution, especially with prssure infusin pumps, into the CVP line, left-sided heart failure"
|
|
|
Term
| Hemodynamic parameter useful for estimating left ventricular preload |
|
Definition
|
Measurement of PCWP (pulmonary capilary wedge pressure)
|
|
|
Term
| Parameter used to assess left ventricular afterload |
|
Definition
|
|
Term
| Medication associated with dilated and fixed pupils in the ICU patient |
|
Definition
|
|
Term
| Level of ICP at which venous drainage be impeded and cerebral edema develop in uninjured tissue |
|
Definition
|
|
Term
| The types of noninvasive monitoring |
|
Definition
|
"pulse oximetry, capnography, transcutaneous monitoring of blood gases, indirect calorimetry, bedside lung function testing"
|
|
|
Term
| Reliability of the visual recognition of hypoxemia by physical examination |
|
Definition
|
"unreliable due to intraobserver variability, differences in skin pigmentation, interference from ambient lighting"
|
|
|
Term
| Causes of hypoxemic events in mechanically ventilated patients |
|
Definition
|
"apnea, airway obstruction, equipment failure or disconnection, inccorrect gas flow setting"
|
|
|
Term
| Two physical principles of pulse oximetry |
|
Definition
|
spectrophotmetry and optical plethysmography
|
|
|
Term
| The Beer-Lambert law and spectrophotometry related to bound oxygen |
|
Definition
|
"Spectrophotometry estimates the amount of oxygen bound to hemoglobin by relying on the Beer-lambert Law, which states that the concentration of light-absorbing species (hemoglobin/oxyhemoglogin) in a sample is a logarithmic function of the amount of light absorbed by the sample (blood, tissue)"
|
|
|
Term
| 2 wavelengths of light and the differentiation of oxyhemoglobin from deoxygenated hemoglobin |
|
Definition
|
"oxyhemoglobin can be differentiated from deoxygenated hemoglobin by shining two wavelengths of light (660 and 940 nm ) through the sampling site. At a wavelength of 660 nm (red light), deoygenated hemoglobin absorbs more light than oxyhemoglobin. Conversely, oxyhemoglobin absorbs more light at 940 nm (infrared light) than does deoxygenated hemoglobin"
|
|
|
Term
| Operational principle of optical plethysmography |
|
Definition
|
"estimates the pulse rate by relating cyclical changes in light transmission through the sampling site with blood volume changes that occur during ventricular systole and diastole. As local blood volume increases during ventricular systole, light absorbancy increases and transmitted light decreases and as blood volume decreases during diastole, absorbency decreases and transmitted light increases"
|
|
|
Term
| How pulse oximeter saturations less than 80% should be confirmed |
|
Definition
|
"laboratory analysis of ABGs, including CO-oximetry."
|
|
|
Term
| Physiological and technical factors influencing the accuracy of pulse oximetry measurement |
|
Definition
|
"Technical - calibration of machines, algorithms used. Low perfusion states, dysfunctional hemoglobins and dyes, variations in skin pigmentation, ambient light interference, nail polish, "
|
|
|
Term
| Effect of significant levels of COHb on the estimation of SpO. |
|
Definition
|
"abnormal hemoglobin, such as carbosyhemoglobin (smoke exposure), produces an erroneously high SpO2. If an abnormal hemoglobin ins suspected, a Co-Oximeter should be used to evaluate the oxygen saturation."
|
|
|
Term
| Criteria used to prescribe oxygen therapy in neonates |
|
Definition
|
"Although it is generally used to trend oxygen saturations in neonates, pulse oximetry is not used to prescribe oxygen therapy in neonates because most neonatologists prefer to base oxygen therapy decisions on PaO2 rather than oxygen saturations"
|
|
|
Term
| Convert values of SaO to PaO |
|
Definition
|
"The SaO2 varies with the paO2 in a sigmoidal, or S-shaped manner. Above 90% sats, PaO2 may rise considerably without much change in SaO2. Below 80% saturation, PO2 falls rapidly"
|
|
|
Term
| Compare and contrast Capnometry with capnography |
|
Definition
|
capnography describes the continuous display of CO2 concentrations as a graphic waveform called a capnogram; capnometry involves the display of exhaled CO2 numerically without a waveform
|
|
|
Term
| Capnometry method employed by resuscitation bags with CO detectors |
|
Definition
|
chemical capnometers that are hand-held devices composed of specially treated filter paper in a plastic casing that can be attached to ET tube. The amount of CO2 present in the pt inspired and expired gas can be estimated by color changes in the filter paper
|
|
|
Term
| Method of estimating the concentration of CO2 in a gas sample most appropriate for end-tidal measurements for mechanical ventilation
|
|
Definition
|
|
Term
| Explain the four phases of waveform displays for the fractional concentration of expired CO 2 (F eCO 2) versus time
|
|
Definition
|
"Phase 1- initial gas exhaled is from conducting airway, containing low levels of CO2 from inspired air. Phase 2 - alveolar gas containing CO2 mixes with gas from anatomical airways, and the CO2 concentrations rises. Phase 3 - the curve plateaus as alveolar gas is exhaled (referred to as end-tidal CO2 or PetCO2. Phase 4 -(inspiration) concentration falls to zero"
|
|
|
Term
|
Definition
|
"during mechanical ventilation, over-distension of more compliant areas of the lung may result in volutrauma, which is a characteristic shape sometimes said to have a ""duck-billed"" appearance"
|
|
|
Term
| Effect of PPV on the conductive airways |
|
Definition
|
"With PPV, the conductive airways INCREASE in size, INCREASING dead space"
|
|
|
Term
| Pulmonary changes caused by the use of 100% O2 in adults |
|
Definition
|
Adults can breathe FIO2 up to .5 for extended periods without damage; use of 100% O2 can cause pulmonary changes in as little as 6 hours
|
|
|
Term
| Easiest way to detect air trapping or auto-PEEP |
|
Definition
|
the flow-time curve on the ventilator graphic
|
|
|
Term
| Consequences of repeated opening and closing on alveoli as seen in atelectrauma |
|
Definition
|
"Shear stress, surfactant alteration, biotrauma"
|
|
|
Term
| Consequences of repeated opening and closing of alveoli on surfactant |
|
Definition
|
"A second consequence of the repeated opening and closing of alveoli produces the problem that in the alveolus, surfactant forms a molecular layer between air and liquid, during collapse the surface area decreases and the surfactant molecules can form together until some pop."
|
|
|
Term
| "Calculate ejection fraction, given weight and stroke volume of a patient" |
|
Definition
|
"ratio of stroke volume to ventricular end-diastolic volume . 70KG male, stroke volume 70 mL, end-diastolic volume of 140 mL. Ejection fraction would be .5 (70/140)"
|
|
|
Term
| Corticosteroids in the treatment of pulmonary fibrosis following ARDS |
|
Definition
|
some ARDS pts suffer from abundant fibroproliferation during recovery from ARDS; pts treated with corticosteroids had improved gas exchange and low mortality
|
|
|
Term
| Use of inhaled nitric oxide in patients with ARDS |
|
Definition
|
NO is a potent vasodilator; diffuses readily through various tissues; the use in ARDS pts based on theory that it will be preferentially distributed to well-ventilated portions of the lung where it will cause local vasodilation; well-vented areas of the lung wld rec greater portion of pulmonary blood flow resulting in improved oxygenation and reducing v/q mismatch. studies of NO in pts with ARDS have variable results
|
|
|
Term
| First electrically powered negative pressure ventilator |
|
Definition
|
iron lung; surrounded body except for head and neck used in 20's - 60's
|
|
|
Term
| Why IPPB declined in the 1980s |
|
Definition
|
"a randomized, controlled trial rvealed no benefit, compared with results of the use of a small-volume nebulizerin the tx of pts with COPD"
|
|
|
Term
|
Definition
|
avoiding intubation and positive pressure ventilation; relieve symptoms associated with hypoventilation and improve quality of life; enhance gas exchange; improve patient-vent synchronization; maximize pt comfort; decrease length of stay; relieve or improve symptoms; increase survival; improve mobility
|
|
|
Term
| Potential benefits for the COPD patient treated with NPPV |
|
Definition
|
shows a reduction for the need for intubation ; reduction in in-hospital mortality; reduced length of stay; fewer complications
|
|
|
Term
| Respiratory diseases treated with NPPV |
|
Definition
|
"COPD exacerbation; asthma, acute cardiogenic pulmonary edema; community -acquired pneumonia; hypoxemic respiratory failure; immunocompromised state; do-not-intubate orders; postop status; difficulty weaning; restrictive thoracic disease; COPD; nocturnal hypoventilation"
|
|
|
Term
|
Definition
|
apnea; hemodynamic or cardiac instability; uncooperative behavior; facial burns; facial trauma; high risk of aspiration; copious secretions; anatomic abnormalities interfering with gas exchange
|
|
|
Term
| Benefit of NPPV used for patients with hypoxemic respiratory failure |
|
Definition
|
"reduced intubation rate, length of stay in ICU, and mortality rate"
|
|
|
Term
| First therapy for acute pulmonary edema |
|
Definition
|
|
Term
| benefits of using NPPV during weaning |
|
Definition
|
"reduced weaning time, length of ICU stay, incidence of nosocomial pneumonia, 60-day mortality compared with the results of conventional weaning"
|
|
|
Term
| Patient requirements for successful NPPV |
|
Definition
|
"cooperative, able to maintain patent airway, able to clear secretions"
|
|
|
Term
| NPPV benefit for patients with restrictive thoracic disease |
|
Definition
|
"postpolio syndrome, neuromuscular disease, chest wall deformities, spinal cord injuries, severe kyphoscoliosis. Ability of NPPV to rest the respiratory muscles, lowers PaCO2 which resets the central ventilatory controller and reestablish a baseline PaCO2, improvement of lung compliance, volume, and deadspace"
|
|
|
Term
| Validity of prophylactic use of NPPV |
|
Definition
|
discouraged; pts with restrictive disease should have sumptoms of nocturnal hypoventilation beore NPPV is considered
|
|
|
Term
| Benefits of long-term use of NPPV in patients with COPD |
|
Definition
|
"improves gas exchange and and unloads the respiratory muscles, allowing the muscles to recover, gain strength, and reduce fatigue. Pts with severe COPD have poor sleep quality, shorter sleep time, and nocturnal hypoventilation which improves with NPPV"
|
|
|
Term
| Predictors of successful use of NPPV in the respiratory failure patient |
|
Definition
|
"minimal air leak, low severity of illness, respiratory acidosis (PaCO2 >45 but < 92), pH <7.35 but but > 7.22, improvement in gas exchange within 30 mins to 2 hrs of initiation, improvement in RR and HR"
|
|
|
Term
| NPPV for moderate to severe cases of nocturnal hypoventilation |
|
Definition
|
recommendations for the use of NPPV in the mgmt of nocturnal hypoventilation due to disorders other than restrictive lung disease and COPD include documentation of a disorder that causes hypoventilation and failure of the disorder to respond to first line therapy
|
|
|
Term
| Most commonly used interface to apply NPPV |
|
Definition
|
"nasal mask, full-face mask, mouthpiece"
|
|
|
Term
| Acceptability of small leaks round the nasal mask in the use of NPPV |
|
Definition
|
"small leak can be tolerated since caution must be taken not to overtighten the straps on the mask, because of excessive pressure on the bridge of the nose can cause tissue necrosis"
|
|
|
Term
| Interface for NPPV better tolerated |
|
Definition
|
full-face mask and nasal pillow improved ventilation more than nasal mask but that the nasal mask was better tolerated
|
|
|
Term
| Interface improving tidal volume the most in the use of NPPV |
|
Definition
|
|
Term
| Consistency of FIO2 in the use of noninvasive ventilators for the administration of NPPV
|
|
Definition
|
rarely constant owing to varying levels of of flow that depend on pt effort and leaks
|
|
|
Term
| Common modes on noninvasive ventilators. |
|
Definition
|
"CPAP, spontaneous (pressure assist), and timed (pressure limited, time cycled)"
|
|
|
Term
| Mode of ventilation most often used for NPPV when a critical care ventilator is in use |
|
Definition
|
"PSV which is pressure-limited, flow-cycled"
|
|
|
Term
| Best response for a leak preventing the appropriate termination of the inspiratory cycle |
|
Definition
|
inspiration can be time cycled instead of flow cycled by changing the mode
|
|
|
Term
| Appropriate actions for patient receiving NPPV with a full face mask and air leak caused by an Ng tube |
|
Definition
|
repositioning the mask and using a flat piece of petroleum gauze between the mask and the NG tube and between the NG tube and the pts fce will produce a better seal
|
|
|
Term
| Factors that determine ventilator for NPPV |
|
Definition
|
determined by the clinician's and staff's familiarity and experience
|
|
|
Term
| Characteristics of Home Care Ventilators for delivering NPPV |
|
Definition
|
"electrically powered and microprocessor controlled. Operate from alternating current (AC) or direct current (DC). DC can be battery operated and can provide backup if AC goes out. Single-limb vent circuit with true exhalation valve. Prevents rebreathing of carbon dioxide. operate only with pressure triggering, which has been associated with increased insp work to trigger a breath. flow is limited ot sine wave which may limit the available flow to a pt with strong drive to breathe"
|
|
|
Term
| Remedy for nasal congestion during the use of a nasal mask for NPPV |
|
Definition
|
"application of heated humidity, cold passover humidification does not relieve"
|
|
|
Term
| Initial setting for inspiratory positive airway pressure (IPAP) when delivering NPPV in the pressure triggered timed mode
|
|
Definition
|
|
Term
| ABG goal of NPPV for COPD patient with hypercarbia |
|
Definition
|
increasing IPAP increases change in pressure and should increase delivered tidal volume which decreases PaCO2
|
|
|
Term
| Physiologic effect of raising EPAP |
|
Definition
|
"increases pts functional residual capacity, mean airway pressure, and PaO2"
|
|
|
Term
| Result of decreasing EPAP in the patient being ventilated using NPPV |
|
Definition
|
change in pressure increases
|
|
|
Term
| Best option for patient who continues to deteriorate 30 minutes after start of NPPV |
|
Definition
|
|
Term
|
Definition
|
"ER, critical care unit, intermediate care unit, hospital ward"
|
|
|
Term
| Patient population accepted for NPPV in the hospital ward |
|
Definition
|
hypercapnic COPD pts with a pH of 7.3 or greater
|
|
|
Term
| Common complication associated with NPPV |
|
Definition
|
"mask related - discomfort, facial skin erythema, claustrophobia, nasal bridge ulceration, acneiform rash. Air pressure or flow-related: nasal congestion, sinus or ear pain, eye irrtation, gastric insufflation; Air leaks; major: aspiration pnemonia, hypotension, pneumothorax"
|
|
|
Term
| Techniques to avoid claustrophobia when using a face mask |
|
Definition
|
"smaller mask, sedative, have pt hold mask in place while therapy is initiated, encouraging the pt"
|
|
|
Term
| Types of scalars displayed during mechanical ventilation |
|
Definition
|
"6 shapes are produced using scalars - rectangular (square), descending (decelerating), Ascending (accelerating), sinusoidal (sine), exponential rising, exponential decaying"
|
|
|
Term
| Coordinate system used to display on a ventilator loop graphic |
|
Definition
|
|
Term
| "The graphical and mathematical representation of the relationship, �the pressure delivery to the lungs will depend on the stiffness of the lung�" |
|
Definition
|
|
Term
| "The graphical and mathematical representation of , �The greater this pressure gradient, the faster the flow of gas and the sooner the lungs fill" |
|
Definition
|
|
Term
| Range of gas pressure sources in newer microprocessor ventilators producing constant flow of gas during inspiration for any clinical situation |
|
Definition
|
|
Term
| "Constant flow, flow-time curve representation relative to x-axis" |
|
Definition
|
a straight line parallel to the x-axis
|
|
|
Term
| Display rate of rise in volume with constant flow |
|
Definition
|
"with a constant flow, the rise in volume is delivered at a CONSTANT rate (linear rise)"
|
|
|
Term
| "Appearance of the alveolar pressure curve, compared to the volume delivery curve" |
|
Definition
|
"alveolar pressure curve will resemble in appearance the volume delivery curve, regardless of the type of volume wafeform that is present"
|
|
|
Term
| "Comparison of the curve representing PTA, to the curve for flow" |
|
Definition
|
"The PTA curve always resembles the flow curve, regardless of the type of flow waveform present"
|
|
|
Term
| Mathematical and graphical depiction of inspiratory time is defined as the amount of time it takes for the volume to be delivered given the amount of flow provided |
|
Definition
|
is defined as the amount of time it takes for the volume to be delivered given the amount of flow provided
|
|
|
Term
| Configuration of flow scalar for a volume-targeted breath with a constant inspiratory gas flow |
|
Definition
|
rectangular or square ramp
|
|
|
Term
| Configuration of flow scalar for PC CMV mode of ventilation |
|
Definition
|
"scalars for a long T1. flow drops to zero before the end of the set inspiration time. The pressre and volume scalars have an end-inspiratory plateua. Scalars for shorter T1. when T1 is short, alveolar pressure does not reach the set pressure, therefore no plateau pattern is seen in the pressure and volume curves"
|
|
|
Term
| Flow pattern to reduce the risk of barotrauma on PCV |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Conditions that can increase the volume of CO produced relative to metabolism |
|
Definition
|
"fever, sepsis, hyperthyroidism, and seizures "
|
|
|
Term
| "Explain transcutaneous monitoring electrodes, heat range, attachment to skin" |
|
Definition
|
"Noninvasive way of indirectly assessing ABGs. Uses modified blood gas electrodes to measure O2 and CO2. Attached to surface of skin with a double sided adhesive ring, electrode is heated to 42 to 45 degrees C"
|
|
|
Term
| "Compare the correlation of PtcO2 (transcutanous) , and PAO2 (PtcO2/PaO2 index in both neonates and critically ill patients" |
|
Definition
|
"the correlation is good for neonates, however it is unreliable for critically ill adult patients"
|
|
|
Term
| Explain the theory of indirect calorimetry including the respiratory exchange ratio (R). |
|
Definition
|
"allows clinician to estmate energy expenditure from measurements of O2 consumption. Based on theory that all energy the body uses is derived from the oxidation of carbs, fats and proteins and that th eratio of O2 produced to O2 consumed (I.e. RQ)is characteristic for the particular fuel burned"
|
|
|
Term
| Types of flowmeters used to monitor gas flow during mechanical ventilation |
|
Definition
|
"vortex ultrasonic flowmeters, variable orifice pneumotachometers, and turbine flowmeters"
|
|
|
Term
| The physiologic events that occur during isovolumetric contraction |
|
Definition
|
"ventricular systole begins with a period of isovolumetric contraction, which coincides with the peak of the R wave on the electrocardiogram"
|
|
|
Term
|
Definition
|
filling pressure of the ventricle at the end of ventricular diastole
|
|
|
Term
| Atrial systole can be observed on the atrial pressure tracing as which wave |
|
Definition
|
|
Term
| Definition of dicrotic notch (incisura). |
|
Definition
|
small negative deflection on the downslope of the aortic and pulmonary artery tracing
|
|
|
Term
|
Definition
|
the impedence the left and right ventricles must overcome to eject blood intot he great vessels
|
|
|
Term
| Definition of the strain gauge transducer used in hemodynamic monitoring systems |
|
Definition
|
"uses an electric circuit known as a wheatstone bridge. Fluid enters the dome portion of the transducer by way of the fluid-filled plastic line. A diaphragm separates the fluid from the electronic portion of the transducer. Changes in pressure in the fluid result in moveent of the diaphragm, which causes an incrase or decrease in the length of wife of the wheatstone bridge"
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Term
| Insertion sites for the arterial pressure catheter |
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Definition
|
"peripheral artery such as radial, brachial or femoral. Raidal is most common good collateral circulation from ulanr arteries, easy location"
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Term
| Definition of the Swan-Ganz catheter |
|
Definition
|
"multiple lumen catheter made of radiopaguq polyvinylchloride. 110 cm long and available in 7 or 8 french. Balloon-tip, flow-directed catheter for bedside catheterization of the right heart and pulmonary artery"
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Term
| How the positioning of the pulmonary artery catheter is accomplished. |
|
Definition
|
by fluoroscopy or by monitoring the pressure tracings generated as the catheter is slowly advanced into the right heart and ulmnary artery
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Term
| Definition of the wedge pressure tracing |
|
Definition
|
"registers a left atrial waveform (i.e. a, c and v waves)"
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Term
| The systolic pressure range of the pulmonary arterial waveform |
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Definition
|
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Term
| The influence of intrathoracic pressure, caused by respirations, on pulmonary artery pressure tracing
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Definition
|
The baseline of PA pressure tracing shows characteristic respiratory-fluctuations arising from intrathoracic pressure
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Term
| Normal cardiac index for an adult |
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Definition
|
|
Term
| Causes of decreased stroke volume |
|
Definition
|
"a decrease in sympathetic tone, such as occurs with a beta-adrenergic blockage; an increase in parasympathetic tone; and various types of bradyarrythmias"
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Term
| The most significant risk of the assessment of the pulmonary capillary wedge pressure |
|
Definition
|
ventricular tachycardia or fibrillation
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Term
| how to calculate cardiac output |
|
Definition
|
"C.O. = VO2/[(CaO2-CvO2) x 10)] - C.O. is cardiac output, VO2 is oxygen consumption, CaO2 is oxygen content of arterial blood, and CvO2 is the oxygen content of mixed venous blood"
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Term
| Cause of mixed venous O2 values decreasing |
|
Definition
|
when arterial oxygenation is decreased
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Term
| Causes of systemic vascular increase and decrease |
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Definition
|
"increased in left ventricular failure, and hypovolemia arising from vasoconstriction caused by stimulation of the baroreceptor reflex; if blood viscosity increases (polycythemia), increases during periods of alveolar hypoxia or when high intraalveolar pressures are generated, such as during PPV, low cardiac output can increase by causing derecruitment of pulmonary vessels. Decreases with systemic vasodilation, such as occurs in moderate hypoxemia or with administration of systemic vasodilators such as nitroglycerin or hyralazine"
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Term
| The use of ejection fraction and cardiac index in the prognosis of heart failure |
|
Definition
|
serves as an estimate of ventricular contractility. EF shows a positive correlation with the CI in most cases and it is an important variable in the prognosis.
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Term
| Variables manipulated during mechanical ventilation oxygenation strategies |
|
Definition
|
"Increase the Paw (PIP, PEEP, I:E ratios, f, and inspiratory flow all affect the Paw)"
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Term
| "Calculate new FIO2 for a desired PaO2 , given PaO2 and the FI O2 . " |
|
Definition
|
known PaO2/known FIO2 = desired Pa02/desire FiO2
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Term
| Values of FIO2, and the partial pressure of O2 in the arteries (PaO2 ) to prevent the complications of O2 toxicity
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|
Definition
|
.4 - .5 while maintaining PaO2 between 60 mmHg and 90 mmHg
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Term
| The use of O2 saturation measured by a pulse oximeter (SpO2 ) to titrate FI O2 . |
|
Definition
|
If a higher than ideal FIO2 is required (greater than .5) SpO2 can be used to titrate the FIO2 with a goal of SpO2 > than 90%
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Term
| Factors that increase Paw during PPV |
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Definition
|
"PIP, PEEP, I:E ratios, f, and inspiratory flow all affect the Paw"
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Term
|
Definition
|
"the loss of surfactant can be a result of damage to surfactant-producing cells (type II) leakage of plasma proteins that inhibit surfactant production, or presence of inflammatory mediators (cytokines)"
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Term
| devices used to apply the positive pressure employed with CPAP or PEEP to the airway. |
|
Definition
|
"Commonly applied to the airway with a mask, nasal prongs, endotracheal tube, or tracheostomy tube"
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Term
| Device that provides a constant pressure throughout expiration regardless of the rate of gas flow or ventilation
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|
Definition
|
a threshold resistor is a device that provides a constant pressure throughout expiration regardless of the rate of gas flow
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Term
| Profound cardiopulmonary side effects caused by too much PEEP |
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Definition
|
"it is not associated with profound cardiopulmonary side effects, such as decreased venous return, decreased cardiac output, decreased blood pressure (BP), increased shunting, increased Vd/Vt, barotrama, and voluntrauma"
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Term
| Beneficial effects of optimum PEEP |
|
Definition
|
"increased oxygen transport, FRC, compliance, and decreased shunt"
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Term
| Specific clinical disorders that may benefit from the use of PEEP |
|
Definition
|
"ALI or ARDS, cardioenic pulmonary edema, bilateral, diffuse pneumonia"
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|
|
Term
|
Definition
|
if a patient's clinical condition indicates PEEP or CPAP is warranted
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|
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Term
| PEEP adjustment and it�s effect on the sensitivity control |
|
Definition
|
The sensitivity control needs to be reset after PEEP is adjusted
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|
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Term
| Effect of too much PEEP on cardiac output |
|
Definition
|
it decreases cardiac output
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|
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Term
| Absolute contraindications for PEEP therapy |
|
Definition
|
untreated tension pneumothorax or tension pneumothorax
|
|
|
Term
|
Definition
|
"signifies too much PEEP has been added, can be expected to cause a drop in cardiac output and increase in Vd/Vt ratio"
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Term
| Effect on the lungs of PAOP (pulmonary artery occlusion pressure ) rising related to increasing PEEP |
|
Definition
|
"when PEEP rises, PAOP may be markedly decreased because pulmonary blood flow is reduced as a result of decreased venous return to the right side of theart"
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Term
| Methods of enhancing O2 transport if cardiac output is low |
|
Definition
|
"slightly reducing PEEP, volume loading (administration of fluids), and/or inotropic agents (dopamine, hydrochloride)"
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Term
| The point in the pressure-volume loop used to set PEEP |
|
Definition
|
set PEEP above the upper inflection point detected during deflation of the lung (deflection point)
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Term
| Sign of alveolar recruitment as PEEP is increased |
|
Definition
|
if PaO2 is markedly increased
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|
|
Term
|
Definition
|
"in primary ARDS, lungs are mostly consolidated. In secondary, alveolar collpase is predominant. A lung recruitment maneuver is more likely to improve oxygenation and compliance of the lung in secondary ARDS because of this "
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|
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Term
| Several types of recruitment maneuvers currently being used in the clinical setting |
|
Definition
|
"sustained high pressure in the CPAP mode, PCV with single high PEEP level imposed, PCV with progressive increases in PEEP level, and sigh maneuvers"
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|
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Term
| Ventilator settings based on the ARDS Network trial and other studies |
|
Definition
|
Vt of 6 mL/kg and Pplat <30 cm H2O
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Term
| Examples of barotraumas resulting from mechanical ventilation |
|
Definition
|
"barotrauma is extraalveolar air and can be in the form of: subcutaneous emphysema, pneumothorax, pneumomediastinum, pneumoperitoneum, and pneumopericardium"
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|
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Term
|
Definition
|
"when ventilation is delivered with a high Vt The resulting overventilation and distortion of cells which causes the release of proinflammatory mediators, particularly chemokines and cytokines - the end result is sometimes indistinguishable from ARDS"
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Term
| Explanation of atelectrauma |
|
Definition
|
"repeated opening and closing of lung units at lower lung volumes. It causes shear stress, alteration and washout of surfactant, and microvascular injury"
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|
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Term
| Explanation of the term VALI |
|
Definition
|
"Ventilator Induced Lung Injury - lung injury occurring at the acinus - the microscopic level of injury seen in biotrauma, shear stress, and surfactant depletion"
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Term
| Characteristics of tension pneumothorax |
|
Definition
|
occurs when air enters the pleural space but cannot leave. Pressure gradually builds collapsing the affected lung. Mediastinal structures will shift in the thorax away from the area of tension and put pressure on the heart and the unaffected lung. tracheal deviation and neck vein distention are possible signs
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|
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Term
|
Definition
|
decrease mean airway pressures as much as possible while using manual ventilation with a high FIO2
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Term
|
Definition
|
|
Term
| How mechanical ventilation can contribute to multiple-organ dysfunction syndrome |
|
Definition
|
"chemical mediators produced in the lung, can leak into the blood vessels which the circulation carries to all the organs setting off inflammatory reactions"
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Term
| Lung-protective strategies employed during mechanical ventilation |
|
Definition
|
treating patients with ARDS with lung protective strategies such as low Vt and PEEP therapy is associated with a decrease in morbidity an dmortality rates.
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|
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Term
| "Effect of PEEP levels above, and below, the opening pressure for recruitable alveoli" |
|
Definition
|
"In ALI, PEPP seems to offer some protection from tissue damage from high pressures. This is especially true if PEEP levels are greater than the opening pressure for recruitable alveoli. PEEP helps restore functional residual capcity by recruiting rpeviously collapsed alveoli. Adequate levels of PEEP prevent repeated collapse and reopening of alveoli and help maintian lung recruitment.. if PEEP overinflates already patent alveoli, increasing PEEP for a given Vt may maximally stretch alveoli and additionally may affect cardiac output"
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|
|
Term
|
Definition
|
"adequate levels of PEEP reduce the reopening an dcollapsing of lung tissue, keeping the recruited lung open at end expiration, ards network trial supports using Vt of 6 and Pplat less than 30"
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|
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Term
| Positive effects of PEEP in ALI and ARDS |
|
Definition
|
"FRC is increased when collpased alveoli open up, improvement of the V/Q relationships of the lungs, improved oxygenation"
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|
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Term
| Characteristics of ventilator-associated pneumonia |
|
Definition
|
pneumonia acquired 48 hours after intubation
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|
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Term
| Strategies for reducing the risk for colonization and VAP |
|
Definition
|
"preventing airway contamination and carefully managint the patient - hand washing, oropharygeal cleaning and decontamination, noninvasive ventilation semirecumbent patient positionaing and enteral feeding"
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|
|
Term
| List the costs and benefits associated with noninvasive ventilation |
|
Definition
|
reduces need for intubation; reduces nosocomial infection; shortens stay in ICU; shortens hospital stay; reduces mortality; preserves airway defenses; improves pt comfort; reduces need for sedation; alleviates symptoms of chronic hypoventilation; improves duration and quality of sleep; improves functional capacity; prolongs survival;
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|
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Term
| three basic methods of applying noninvasive ventilation |
|
Definition
|
negative pressure; abdominal displacement; positive pressure
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|
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Term
|
Definition
|
the rocking bed and intermittent abdominal pressre ventilator
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|
|
Term
| Principle of abdominal displacement ventilation |
|
Definition
|
movement of the abdominal contents and diaphragm to fascilitate breathing
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|
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Term
| Benefits of NPPV over IPPV |
|
Definition
|
avoidance of intubation;reduces nosocomial infection; shortens stay in ICU; shortens hospital stay; reduces mortality; preserves airway defenses; improves pt comfort; reduces need for sedation; alleviates symptoms of chronic hypoventilation; improves duration and quality of sleep; improves functional capacity; prolongs survival;
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|
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Term
| Complications associated with endotracheal intubation |
|
Definition
|
"airway trauma, increased risk for aspiration, nosocomial pneumonia, and patient discomfort resulting in use of sedatives"
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|
|
Term
| The physiological goal of NPPV in acute respiratory failure |
|
Definition
|
the avoidance of intubation and invasive ventilation
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|
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Term
| Immediate improvements in patients with COPD receiving NPPV |
|
Definition
|
reduces inspiratory muscle activity and respiratory rate and increases Vt and and minute volume allowing for better gas exchange and respiratory muscle rest
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|
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Term
| NPPV is currently considered a standard of care to treat this disease in selected patients |
|
Definition
|
moderate to severe exacerbations of COPD
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|
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Term
| The use of CPAP with O2 to expand fluid-filled alveoli |
|
Definition
|
"when patients with CPE (cardiogenic pulmonary edema) do not respond to conventional pharmacological and oxygen therapy, the use of mask CPAP with oxygen may expand fluid-filled alveoli, resulting in increased oxygenation; increased FRC; improved lung compliance; reduced WOB; reduced need for invasive ventilation; shorter ICU stay; improved mortality rate"
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|
|
Term
| NPPV compared with CPAP in the treatment of CPE |
|
Definition
|
several studies have shows similar success in treating CPE (cardiogenic pulmonary edema) with NPPV by mask using PSV plus PEEP - patients who were already hypercapnic showed the greatest improvement
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|
|
Term
| Clinical disorders where NPPV can be useful in chronic cases as supportive therapy |
|
Definition
|
"disorders characterized by chronic hypoventilation, nocturnal desaturtion, respiratory muscle fatigue, and poor sleep quality"
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|
|
Term
|
Definition
|
"increses Vt, reduces diaphragmatic activity, improves oxygenaton"
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|
|
Term
| Disorders associated with nocturnal hypoventilation that generally benefit from NPPV |
|
Definition
|
"central sleep apnea, obesity hypoventilation syndrome, and OSA combined with COPD or CHF"
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|
|
Term
| symptoms of chronic hypoventilation that may be indications for NPPV |
|
Definition
|
"fatigue, morning headache, daytime hypersomnolence, cognitive dysfunction, dyspnea"
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|
|
Term
| Physiologic advantages of NPPV used after extubation in patients who exhibit fatigue |
|
Definition
|
reduces WOB and maintains adequate gas exchange as efffectively as invasive ventilation
|
|
|
Term
| Symptoms and selection criteria for NPPV in acute respiratory failure |
|
Definition
|
"symptoms; RR> 24, use of accessory muscles, paradoxical breathing - selection critera; PaCO2>45 torr, pH <7.35, OR PaO2/FiO2 < 200"
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|
|
Term
| Physiological criteria for commitment to NPPV |
|
Definition
|
"acute exacerbations of COPD, acute asthma, hypoxemic respiratory failure, community-acquired pneumonia, cardiogenic pulmonary edema, immunocompromised patients, postoperative patient; postextubation (weaning) status; ""do not intubate"" status"
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|
|
Term
| The most common problem of nasal mask NPPV |
|
Definition
|
air leaks and skin irritation
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|
|
Term
|
Definition
|
"IPAP gradually is reduced to a minimum level, allowing the patient to assume more of the WOB. Once the minimum level has been reached, NPPV can be discontinued"
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|
|
Term
| Characteristics of APRV mode of support |
|
Definition
|
"a mode of ventilatory support designed to provide two levels of continuous positve airway pressure and allow spontaneous breathing at both levels when spontaneous effort is present. Moderately high level of pressure. High and low pressure levels are time triggered and time cycled when spontaneous efforts are not detected. can be accompanied by patient triggering when spontaneous breathing. if pt is not spontaneously breathing, pressure curve is like pressure controlled inverse ratio ventilation. "
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|
|
Term
| Comparison of factors reduced with PCIRV and APRV |
|
Definition
|
APRV improves gas exchange and lowers PIP in patients with ALI compared with patients receiving volume-controlled invese ratio ventilation
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|
|
Term
| The primary reason for APRV being associated with a reduced risk of ventilator-associated lung injury
|
|
Definition
|
Because APRV can reduce airway pressure In patients with ALI/ARDS
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|
|
Term
| APRV and the need for sedation |
|
Definition
|
patients receiving APRV have been shown to require less sedation and analgesia when compared to those patients receiving continuous mandatory ventilation
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|
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Term
| Conventional mode settings used when changing from to APRV |
|
Definition
|
"when changing from a conventional mode to APRV, the settings on conventional ventilator can serve as a guide to the APRV settings"
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|
|
Term
| The Tlow setting consensus for using APRV in patients with ARDS in the generation of regional intrinsic PEEP (areas of trapped air) and enhanced alveolar recruitment.
|
|
Definition
|
"set the Tlow between 0.5 and 1.0 second, typically at 0.8 second. The Tlow setting should generate regional intrinsic PEEP and enhance alveolar recruitment"
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|
|
Term
| Results of a randomized control trial comparing HFOV and pressure-control ventilation, in adults with ARDS |
|
Definition
|
"an improvement in gas exchange when patients were switched from conventional ventilation to HFO, mortality rate in both studies was directly related to the length of time on conventional ventilation"
|
|
|
Term
| Equivalent respiratory frequency (cycles/minute) of HFOV where gas is oscillated at frequencies between 3 to 15 Hz (Hz = cycles/second |
|
Definition
|
|
Term
| Recommendations for initial settings of HFOV |
|
Definition
|
mPaw (analogous to Paw on conventional ventilation) - 3-5 cm H2O above the observed Paw during conventional ventilation (25- 30); Amplitude starting point of 6-7; frequency 5-6 Hz; Inspiratory time percent 33% (1:2 I:E ratio); bias flow - 25 - 40 L/min
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|
|
Term
| "For HFOV, the FIO2 settings incremental changes to maintain the target range for PaO2 or SpO2" |
|
Definition
|
FiO2 of 1.0 and decreased in increments of 0.1 as tolerated to maintain a range for PaO2 or SpO2
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|
|
Term
| When a recruitment maneuver should be performed during HFOV |
|
Definition
|
"lung recruitment may be an important aspect of HFOV, whether HFOV is being used as a rescue technique or as a primary mode to prevent VILI"
|
|
|
Term
| "For HFOV, settings that critically influence PaCO2" |
|
Definition
|
"increasing frequency reduces Vt, reduces CO2 elimination, and results in a higher PaCO2.decreasing the frequency is accomplished in increments of 1 - 2 Hz until a min of 3 Hz is reached. An upward adjustment of frequency results in an increase in PaCO2, whereas a downward adjustment of frequency results in a decrease in PaCO2"
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|
|
Term
| "Role of mPaw both for HFOV, as well as conventional ventilation modes" |
|
Definition
|
Oxygenaton during HFOV is primarily achieved by maintining mPaw at a level sufficient to obtain optimal lung inflation
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|
|
Term
| The role of sedation and use of analgesics to transition from conventional ventilation to HFOV
|
|
Definition
|
"a strong spontaneous inspiration may reduce circuit pressures below 5 cm H2O which can result in desaturation. For this reason, patients are typically sedated. Paralysis may also be required"
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|
|
Term
| Conditions where Heliox therapy is helpful in treating spontaneously breathing patients |
|
Definition
|
"with acute exacerbation of asthma, central airways are narrowed from mucous plugging, mucosal edema, and smooth muscle constriction increasing turbulent flow and Raw. Heliox can increase peak inspiratory flow rate, reduce the risk of respiratory muscle fatigue until bronchodilator and corticosteroid treatment becomes effective"
|
|
|
Term
| Most commonly used concentration of heliox |
|
Definition
|
80% helium and 20% oxygen
|
|
|
Term
| Special challenges presented by the low density of helium |
|
Definition
|
volume and flow delivery measurements will not be accurate
|
|
|
Term
| Type of ET tube used to deliver ILV |
|
Definition
|
a specialized double-lumen ET tube. Each bronchus receives different volumes and pressures
|
|
|
Term
| List ventilation parameters delivered to each lung during ILV |
|
Definition
|
|
Term
| "ILV effect on functional residual capacity, effective ventilation, and baro/volutrauma" |
|
Definition
|
"increase FRC, and increase effective effective ventilation in the damanged lung reducing the possibility of baro/volutrauma"
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|
|
Term
| Use of ILV and thoracoabdominal aortic aneurism surgical repair |
|
Definition
|
TAAA repair is a procedure that usually results in a unique form of unilateral lung injury. TAAA requires physical compression and deflation of the left lung to allow more free access to the aorta. Right lung ventilation is sustained and made possible with the use of left-sided DLET (double-lumen ET)
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