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151 Cards in this Set
- Front
- Back
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Non-invasive monitoring devices:
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pulse oximetry, capnography, transcutaneous monitoring,
-indirect calimetry -flow measurements -PIP, MAP, Raw, Dynamic and Static Compliance, WOB (graphics), Occlusion pressure measurements |
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Pulse oximetry
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provides continuous noninvasive measurments of arterial oxygen saturation.
-sensor is placed over a digit, earlobe, the forehead, or bridge of the nose. |
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What is the gold standard for monitoring hypoxemia?
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ABG's
-performed intermittenly and may fail to detect transient hypoxic episodes. -expensive |
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Pulse oximetry is based on two physical principles?
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1. spectrophotometry
2. optical plethysmosgraphy |
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Spectrophotometry
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estimates the amount of oxygen bound to hemoglobin by relying on the Beer-Lambert Law.
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660nm
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deoxygenated hemoglobin absorbs more light than oxyhemoglobing
-HHb |
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940nm
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oxyhemoglobin absorbs more light
-O2Hb |
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Optical plethysmography
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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.
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Accuracy of pulse oximetry
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depends ultimately on calibration which is done by the manufacturer.
only > 80% SpO2 |
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Physiological and technical factors that affect Pulse Oximetry
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1. low perfusion states
2. dysfunctional hemoglobins or dyes 3. nail polish 4. skin pigmentation 5. ambient light |
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Low perfusion states
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may render oximeter unable to identify a pulsitile signal accurately
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What are the four hemoglobins?
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-deoxyhemoglobin HHb
-oxyhemoglobin O2Hb -carboxyhemoglobin COHb -methemoglobin MetHb |
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What type of electrode is used in a transcutaneous oxygen monitor?
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Clark electrode
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What type of electrode is used for transcutaneous CO2 measurments?
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Stowe-Severinghaus
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Dysfunctional Hemoglobins
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1. methemoglobin
2. carboxyhemoglobin (COHb) |
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Methemoglobin
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complication of the administartion of high levels of inhaled nitric oxide or benzocaine, and dapsone
-baby w/ high met = blue/grey color |
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Carboxyhemoglobin
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leads to overextimation of SpO2
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Clinical applications of pulse oximetry
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-useful in early warning of hypoxemia
-excellent trending device by displacying a continuous display of SpO2. -useful in intensive care units for titrating FiO2 and PEEP on mechanically ventilated pts. |
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Capnography
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is the measurement of CO2 concentration in respired gases-describes a continuous display (capnogram)
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Capnometry
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involves the display of exhaled CO2 numerically without a waveform.
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How often should a transcutaneous sensor be repositioned?
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4 to 6 hours /neonates more frequently
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IR spectroscopy
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is based on the principle that molecules composed of more than one element absorb IR light in a characteristic manner.
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Classification of IR analyzers
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1. sidestream
2. mainstream |
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Sidestream
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gas from the airway is extracted through a narrow plastic tube to the sample measuring chamber located in a separate console. (possible slight delay)
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Mainstream
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analyzer is attached directly to the ET therefore there is no delay; however, may add deadspace.
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How much CO2 does expired air conatin?
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4.5% to 5.5% as a product of cellular metabolism
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Capnography has proven a useful measurement in two types of breathing pts:
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Spont
Mechanically |
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Indications of Capnography
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1. monitoring the severity of pulmonary disease and evaluating the response to therapy, especially therapy intended to imporve the dead space to tidal volume (VD/VT) adn ventilation/perfusion (V/Q) relationships; it may also provide valuable information about therapy directed at improving coronary blood flow.
2. determining whether tracheal rather than esophageal intubation has taken place. 3. monitoring the integrity of the mechanical ventilatory circuit and artificial airway 4. evaluating the efficiency of mechanical ventilatory support 5. monitoring the adequacy of pulmonary and coronary blood flow 6. monitoring CO2 production |
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Capnography Contraindications
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no absolute condraindications to capnography have been established for mechanically ventilated adult pts.
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Changes in contours of capnogram used to detect?
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increased deadspace, hyperventilation, periodic breathing, hypoventilation, apnea, pharmacologically paralyzed patients, & effective gas exchange during CPR
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Volumetric capnometry
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focuses on exhaled CO2 plotted relative to exhaled volume
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Single breath CO2 curve
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produced by the integration of airway flow and CO2 concentration and is presented on a breath to breath basis
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Ventilation
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pH, PaCO2, HCO3-
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Oxygenation
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PaO2, SaO2, CaO2, DO2
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Common methods of changing ventilation based on PaCO2 and pH
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common to initially use full ventilatory support and then make adjustments after ventilation has been started.
Adjust VE by adjusting Vt adn f (frequency) |
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PaCO2 equation
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Known PaCO2 x Known VE=Desired PaCO2 x Desired VE
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Desired tidal volume
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known PaCO2 x known Vt
--------------------------------------- desired PaCO2 |
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Desired f
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known PaCO2 x known f
------------------------------------ desired PaCO2 |
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Causes of respiratory acidosis
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parenchymal lung problems, airway disease (asthma), pleural abnormalities, chest wall abnormalities, neuromuscular disorders, central nervous system problems
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Recommended guidelines for respiratory acidosis
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VV or PCV = adjust VE
1. Vt 8-12 mL/Kg IBW 2. Pplateau <30cmH2O 3. w/PCV set pressure to obtain targeted Vt 4. increase Ti (may increase volume delivery) |
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Desired P
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desired Vt/Cs
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Causes of respiratory alkalosis
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hypoxia (compensatory hyperventilation), parencymal lung disease, medications, mechanical ventilation, central nervous system disorders, anxiety, metabolic problems
-alveolar ventilation is excessive |
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How do you correct respiratory alkalosis in volume ventilation?
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decrease frequency and if necessary decrease Vt
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How do you correct respiratory alkalosis in PV?
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decrease frequency first, then decrease pressure, if necessary.
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Respiratory alkalosis during SPONT efforts
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may reduce Vt; however, pt may increase spontaneous rate to maintain high alveolar ventilation
-may result in atelectasis -consider another mode: SIMV, PSV -consider sedation |
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Metabolic Acidosis
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pts try to lower PaCO2 to compensate for metabolic acidosis.
-risk of resp. muscle fatigue |
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Causes of metabolic acidosis
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ketoacidosis, uremic acidosis, loss of bicarbonate, renal loss of base following administration of carbonic anhydrase inhibitor (Diamox), overproduction of acid (lactic acid), ingested toxin
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Causes of metabolic alkalosis
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loss of gastric fluid and stomach acids, acid loss in urine, acid shift into the cells, lactate, acetate, or citrate administration, excessive bicarbonate loads.
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hypoxemia
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as PaCO2 rises, PaO2 will decrease
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Increased physiological dead space
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-respiratory acidosis persist even after alveolar ventilation has been increaed, the problem may be with increased dead space.
-dead space can also occur when there is reduced pulmonary blood flow to the lungs i.e. high PEEP -air trapping that results from high VE |
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Treat physiological dead space
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increasing flow or decreasing the I:E ratio (to 1:3 or 1:4), reposition patient so that the diseased compromised lung receives minimal blood flow and non diseased receives greater blood flow. This aids greater blood flow and imporves gas exchange
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Normal VD/VT
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0.2 to 0.4
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Decreased ETCO2 and increased PaCO2 to PetCO2 gradient suggests
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increased deadspace
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Increased metabolism and increased CO2 production
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pts with: fever, burns, multiple trauma, sepsis, hyperthyroidism, muscle tremors or seizures, agitation adn pt who have undergone multiple surgical procedures.
VE increased, increased WOB -increased mechanical rate may cause auto-PEEP. treat with PS or PC-CMV with sedation |
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Intentional Iatrogenic hyperventilation
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used primarily with acute head injury or increased ICP's.
-reduces CO2 in blood which in turn is associated with constriction of cerebral blood vessels and a decrease in blood flow to the brain. |
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Prophylactic hyperventilation
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no longer recommended.
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Permissive hypercapnia
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-normocapnia impossible to maintain w/out risk of lung damage.
-inappropriate use of mechanical ventilation can result in severe lung injury, activation of inflammatory mediators, and potentially lead to multisystem organ failure. -PaCO2 values >50 to 150mmHg. and pH values allowed to fall below normal (7.10 to 7.30) -sedate pts w/ALI increased CO2 levels stimulate the drive to breathe. |
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Procedures for managing PHY
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-allow PaCO2 to rise and pH to fall without changing mandatory rate or volume.
-reduce CO2 production with paralytic agents, cooling pts, restricting glucose intake -administer agents such as NaHCO3-, THAM |
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Contraindication for PHY
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-cerebral disorders (cerebral edema, increased ICP)
-head traumas -intracranial disease -preexisting cardiovascular instability |
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Appropriate suction levels for adults:
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-100 to -120mm Hg (max -150)
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Appropriate suction levels for child:
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-80 to -100 mm Hg (max -125)
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Appropriate suction levels for infants:
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-60 to -100 mm Hg (max -100)
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How to determine the correct suction catheter size based on ET size
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multiply ET size by 3 then divide by 2 to get the size of the Fr suction catheter.
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PaO2 equation
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104.2 - (0.27 x Age)
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Silent aspiration
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may occur due to injury to the mucosa during insertion, interference with normal cough reflex, aspiration of contaminated secretions that pool above the ET cuff, contaminated biofilm around the ETT.
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Hi-Lo Evac endotracheal tube (CASS)
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this is a tube with suction port just above the cuff, designed to remove secretions above the cuff and reduce risk of VAP
-20 mm Hg suggested continuous suction level |
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Cons of instilling saline
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-doesn't thin secretions
-increase risk of dislodging bacteria from the ET (poss. lead to nosocomial pneumonia) -increase vol. of secretions -can make airway obstruction worse -reduce oxygenation -increase risk of infection -increase dyspnea sensation (old pt's) -may irritate airways = severe cough and bronchospasms |
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Administering aerosols to ventilated pts
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bronchodilators, corticosteroids, antibiotics, mucolytics, and surfactants
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What is the most common aerosolized drug administered?
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bronchodilators
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Several factors need to be considered in the delivery of aerosolized drug administration:
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ventilator
pt circuit related |
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Technical problems with adding nebulizers to pt circuits:
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expriatory monitors read differently, added flow may prevent pt triggering due to weak inspiratory muscle strenght, incorrect digital readouts, "gumming" of flow measuring devices and expiratory valve, changed settings sometimes forgotten, contamination.
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Kinetic beds
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automatically turn pts
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Prone positioning
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may improve oxygentation in ALI and ARDs pts
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What are the two methods that can be used to manage ventilatory status of pts with unilateral lung disease?
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1. independent lung ventilation
2. lateral position "good" lung is in the down, or dependent, position |
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What are the three ways to transport a mechanically ventilated pt?
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1. manual ventilation with self inflating bag
2. transport ventilator 3. third generation ICU ventilators |
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Sedations for critically ill pt's are given for the following:
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anxiety, minimization of sleep deprivation, delirium, pain, and adverse drug effects.
also for non conventional modes: high frequency and inverse I:E ratio |
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Four levels of sedation
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1. minimal
2. moderate 3. deep 4. anesthesia |
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Benzodiazepines
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drug of choice for the treatment of anxiety in critical care.
-low cost, able to produce anxiolytic, hypnotic, muscle relaxation, anticonvulsant, and anterograde amnesic effect. -exert their effects through a nonspecific depressionof the CNS. drug binds to benzodiazepine site on the gamma-aminobutyric acid (GABA) receptor complex on neurons in the brain. |
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Effects of Benzodiazepines
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minimal effects on cardiovascular function; however they can cause a significant drop in BP when initially administered to hemodynamically unstable pt's
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Reversal of Benzodiazepines
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flumazenil (Romazicon) which prevents the sedative effects of these drugs by competitively binding to benzodiazepine receptors.
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Diazepam
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(Valium)
-rapid onset of actioin (3-5min) -metabolized in the liver -elimination can be depressed in the elderly, neonates, and pts w/compromixed hepatic and renal function -IV most method -continuous infusion not recommended |
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Midazolam
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(Versed)
-rapid onset of action and short half life -ideal sedative for treatment of acutely agiated pt. -does not cause respiratory depression in most pts but can reduce ventilatory response in COPD pts (reduced upper respiratory response) -minimal hemodynamic effects |
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Lorazepam
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(Ativan)
-most potent benzodiazepine and the drug of choice for sedating MV pts in ICU's for >24hrs. -slower onset of action -longer duration of action -metabolized in the liver -caution req when used with CNS depressants |
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Side effects of Lorazepam?
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lactic acidosis, hyperosmolar coma, and reversible nephrotoxicity
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Opioids
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endogenous and exogenous substances that bind to a group of receptors located in the peripheral tissues.
-primary pharm action is to relieve pain; however, these drugs provid significant secondary sedative and anxiolytic effects which are mediated through two types of opioid receptors: mu and kappa receptors. |
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Side effects of opioids?
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nausea, vomiting, reduced gastrointestinal motility, respiratory depression, bradycardia, hypotension, myocionus (muscle twitching), convulsions, histamine release, immunosuppression, physical dependence.
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Reversal of opioids?
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opioid antagonist, naloxone hydrochloride (Narcan)
-it has a short onset and usually last about 30 minutes. Continous IV infusion required for opioid withdrawal. -smaller doses reverse respiratory depressant while not interfering with analgesic effect. |
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Morphine
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-potent opioid analgesic that is the preferred agent for intermittent therapy because of longer duration of action.
-IV delivery -continuous -slower onset of action than other opioids due to its lower lipid solubility and slower transit time across the blood brain barrier. -renal or hepatic diseases can impair the clearance of morphine and it metabolites. |
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Side effects of morphine:
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produces significant effects on CNS and can alter breathing; decreases VE and even apnea, can reduce cerebral blood flow, ICP and cerebral metabolic activity.
-drowsiness, lethargy dilation of pupils, and cough reflex suppression. -reduce lower esophageal sphincter tone and propulsive peristaltic activity of the intestine. -can alter vascular resistance by causing decreases in sympathetic tone and increased vagal tone; hypotension -increase serum histamine levels which can add to peripheral vasodilation and hypotension. -associated with pruritus and bronchospasm in some individuals. |
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Fentanyl
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(sublimaze)
-synthetic opioid that is approx 100 to 150 x more potent than morphine -high lipid solubility with short transit time across the blood brain barrier-rapid onset -longer half life and can accumulate in the peripheral tissues after prolonged infusion -administered as a leading dose followed by continuous infusion to maintain analgesic effect because of its short duration of action -patches avail |
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Effects fentanyl
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minimal effects on the cardiovascular system and does not cause histamine release.
-opioid of choice for pt hemodynamically unstable. -can cause respiratory depression |
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Neuroleptics
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-routinely used to treat pts demonstrating evidence of extreme agitation and delirium
-used for pt treated in ICUs for prolonged periods of time |
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Haloperidol
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(Haldol)
-butyrophenone that causes CNS depression -less sedative effect than benzodiazepines adn opioids -can cause potentially serious side effects. -onset action 3-20min post intial 5mg dose adminstered IV -add 5mg doses can be given with a max of 200mg -safe drug for treatment of delirium despite potential side effects. |
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Side effects Haloperidol
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possesses antidopaminergic and anticholinergic effects on the heart
-can induce alpha blockage -lower seizure thresholds and evoke Parkinsons like symptoms (muscle rigidity, drowsiness, and lethargy) -dose dependent cardiac dysrhythmias including QT prolongation and torsades de pointes. |
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Anesthetic agents
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Propofol (Diprivan)IV general anesthetic agent that possesses sedative, amnesic, and hyponotic properties at low doses.
-no analgesic properties -administered 1 to 2mg/kg following by continous infusion at a rate of 3 to 6 mg/kg/hr |
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Side effects of Propofol
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reduction in systemic vascular resistance (decreased BP and bradycardia) during initial induction phase.
-reduces cerebral blood flow and ICP -morphine and propofol combined allow for greater control of ICP than morphine alone. -rapid awakening from propofol allows interruption of the infusion of neurological assessment. -clearance appears to be unaffected by renal and hepatic dysfunction Adverse effects: hypotention, dysrhythmias, and bradycardia, elevation of pancreatic enzymes -prolonged use > 48hrs, has been associated with lactic acidosis and lipidemia. |
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Dexmedetomidine
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(precedex)
-short acting, anxiolytic, anesthetic, hypnotic and analgesic properties -promote cooperative sedation -relatively short distribution half life (6 min) -elimination half live of approx 2hrs -minimal hemodynamic side effects |
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Most common use of paralytics:
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1. pt vent dyssynchrony that cannot be corrected
2. facilitation of less conventional mechanical ventilation strategies 3. faciliation of intubation 4. dynamic hyperinflation that cannot be corrected 5. adjuntive therapy for controlling raised ICP 6. reduction of O2 consumption and CO2 produciton |
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Two classes of NMBAs
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1. depolarizing agents
2. nondepolarizing agents |
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Depolarizing agents
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resemble acetycholine and induce paralysis by binding to acetycholine receptors and causing prolonged depolarization of the motor end plate.
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Nondepolarizing
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bind to acetylcholine receptors, but cause paralysis by competitively inhibiting the action of acetylcholine at the neuromuscular junction
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Paralytics
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do not possess sedative or analgesic properties.
-must be used in conjunction with adequate sedatives and analgesics to ensure pt comfort |
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Monitoring neuromuscular blockade
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1. visual, tactile, and electronic assessment of pt's muscle tone
2. train of four (TOF): electronic technique that uses two electrodes placed on the skin along a nerve path. An electral current of 4 impulses applied over peripheral nerve and muscles contractions are produced |
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Depolarizing agents
succinylcholine chloride |
(Anectine)
-short acting (5-10min) -onset of 60 seconds -recommended for inducing paralysis in hemodynamically stable, critically ill pts -administered IV 1 to 1.5 mg/kg |
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Side effects of succinylcholine
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transient hyperkalemia
cardiac dysrhythmia anaphylactic reacitons prolonged apnea postoperative myalgia increased IG, IC, IO pressures myoglobinuria sustained skeletal muscle contraction malignant hyperthermia (rare) |
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Pancuronium
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nondepolarizing agent
(Pavulon) -one of the first nondepolarizing NMBAx used for prolonged paralysis of mechanically ventilated pts. -loading does 0.08 to 0.1mg/kg -maintenance dose 0.05 to 0.1mg/kg/hr -metabolized in the liver |
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Side effects of pancuronium
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-prolonged paralysis after discontinuation
-tachycardia -increased C.O -elevated MAP (vagolytic effect) -alterations in ventilation perfusion relationship as a result of pulmonary vasoconstriction |
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Vecuronium
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(Norcuron)
-intermediate duration -does not possess vagolytic properties -loading dose 0.1mg/kg with maintenance does of 0.05 to 0.1mg/kg/hr -effective in producing prolonged paralysis in pts with renal insufficiency |
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Altracurium/Cisatracurium
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(Tracrium/Nimbex)
-intermediate duration -do not have the hemodynamic side effects as does pancuronium -can cause histamine release and mast cell degranulation at higher doses which can lead to peripheral vasodilation and hypotension -ideal for renal adn hepatic insufficiency |
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Recover from neuromuscular blockade
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typically 1-2 hrs after continuous infusion has been discontinued
-long term tolerance may develop -muscle weakness can occur with prolonged use. |
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Most common parameters used to assess oxygenation status:
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FiO2, SaO2, ABG's, Hb, abnormal Hb, PaO2, PaO2/PAO2, PaO2/FiO2 ratio, shunt, C.O., SvO2, and CvO2
-O2 delivery |
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FiO2
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maintain below .4 to .5 to prevent complications of oxygen toxicity.
-SpO2 used to titrate |
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Desired FiO2
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PaO2 (desired) x FiO2 (known)
-------------------------------------------- PaO2 (known) |
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Mean Airway Pressure
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Paw
-the average pressure above baseline during a total respiratory cycle (I +E) 1/2(PIP-PEEP)x(Tinsp/TCT)+PEEP -major determinant of oxygenation in pts with ARDS because it affects mean alveolar pressure and alveolar recruitment, and therefore oxygenation. |
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What increases Paw?
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-I:E ratio (1:1, 2:1 or higher)
-inflation hold -PEEP -High PIP -increased intrapleural pressures |
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What lowers Paw?
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rapid inspiratory flows
-IMV/SIMV by reducing frequency of mandatory breaths and allowing spont breathing. |
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Positive End Expiratory Pressure
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PEEP
-used to increase Paw and maintain oxygenation |
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Atelectasis
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-partial or complete collapse of previously expanded areas of lung
-tx: correct the cause Causes: blocked air passages, shallow breathing, surfactant deficiency |
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Goals of PEEP
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-enhance tissue oxygenation
-maintain PaO2 above 60mm Hg and SpO2 at or above 90% -recruit alveoli and maintain in aerated state -restore functional residual capacity |
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Flow resistor
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achieve expiratory pressure by creating a resistance to gas flow through an orifice
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Threshold resistor
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a device that provides a constant pressure throughout expiration regardless of the rate of gas flow
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Minimum or Low PEEP
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3 to 5 cm H2O to help preserve a pt's normal FRC
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Therapeutic PEEP
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> or = 5cm H2O. It is used to treat hypoxemia caused by increased intrapulmonary shunting and ventilation perfusion mismatching.
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High levels of PEEP
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>15 cm H2O are beneficial to a small percentage of pt's with ARDS
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Optimum/Best PEEP
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is the level of maximum beneficial effect, i.e. increased O2 transport, FRC, compliance, decreased shunt without profound cardiopulmonary side effects.
Def: the PEEP at which static compliance is highest as PEEP is decreased following a recruitment maneuver |
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Indications for PEEP
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-ARDS
-bilateral infiltrates -recurrent atelectasis -PaO2<60mm Hg on high FiO2 of >50% - PaO2/FiO2 ratio of <200 for ARDS -PaO2/FiO2 ratio of <300 for ALI -refractory hypoxemia |
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Optimum PEEP Study
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-freq. req. PEEP >10cm H20
Assess Pt: appearance, BP, BS, vent. parameters, Cs, arterial PO2, FiO2, and PaO2/FiO2 ratio, arterail PaCO2, pH, P(A-a)O2, arterial EtCO2 tensioin gradient, hemodynamic data, arterial to venous oxygen difference, mixed venous oxygen tension of saturation, and C.O. |
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Static pressure volume
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(SPV)
curves have been used to select a best PEEP level adn Vt in ALI |
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Lower Inflection Point
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(LIP) PEEP levels often set 2-4cm H2O higher LIP
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Upper inflection point
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(UIP) current theory suggest settling PEEP above the UIP detected during deflation of the lung.
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Static Pressure Volume Measurement
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1. super syringe technique
2. inspiratory occlusion technique 3. dynamic pressure volume loops |
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Contraindications and Physiological Effects of PEEP
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-hypovolemia
-untreated significant pneumothorax or a tension pneumothorax -elevated ICP -unilateral lung disorders |
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Pulmonary Effects of PEEP
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-ARDS caused uneven distribuitnon of ventilation
-Lg. Vt may cause overexpansion and high ventilating pressures. -PEEP recruits a certain number of collapsed alveoli -Clinician should ensure Pplateau remains below 30cmH2O |
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Acute Respiratory Distress Syndrome
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severe lung injury and require PEEP to treate severe hypoxemia.
-characterized by increased pulmonary shunt, hypoxemia, increased dead space, and reduced respiratory compliance. P/F ratio <200 |
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Effects of ARDS
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produces stiff lungs (reduced compliance)
-reduced lung vol. (decreased FRC) -parenchymal injury may also affect the airways -weight of lung is double to triple that of normal lungs possibly due to inflamation and edema. |
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Managing ARDS Pt's
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1. use small Vts accompanied with PEEP level to avoid alveolar collapse.
2. maintain minimum end-expiratory volume with PEEP 3. keep in mind PaO2 is not a good indicator of an appropriate PEEP level. 4. apply PEEP early after diagnosis of ARDS 5. low pressures in VV switch to PCV 6. Pplateau <30cmH20 7. consider permissive hypercapnia when risk of damaging lung tissue an issue or when auto PEEP is present. |
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Recruitment maneuver
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a sustained increase in pressure in the lungs with the goal of opening as many collapsed lung units as possible.
Once lungs are recruited, they are kept open by maintaining an adequate PEEP above the LIP of an inspiratory maneuver or preferably above the UIP or a deflation (expiratory) maneuver. |
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Hazards of RM
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-decrease venous return to thorax
-drop in C.O -drop in BP -uneven pressure distribution causing shifting of blood to other areas of the lung |
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Contraindication for lung RM
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bullae (blebs)
pneumothorax |
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Cardiovascular Effects of PPV
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-decreases C.O.
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Frank-Starling mechanism
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increased ventricular preload volume and increased right ventricular stroke volume
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Coronary Blood Flow with PPV
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decreases coronary perfusion and ultimatley leads to MI
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Factors Influencing Cardiovascular Effects of PPV
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-lung and chest wall cmpliance
-Raw -duration and magnitude of positive pressure -compnesatory mechanisms in normal individuals prevent hypotension during PPV -compensatory mechanisms dependent on neuroreflexes -normal vascular reflexes reduce the probability of decreased CO and BP when PPV initiated. |
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Paw Calculation
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1/2(PIP-PEEP)x(Ti/TCT)+PEEP
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Higher peak pressure may be required for pts with increased Raw caused by:
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bronchospasm, mucus plugging, and mucosal edema.
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PPV may decrease:
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-cardiac output
-decrease renal blood flow adn glomerular filtration rates -decrease in urine output |
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Why is nutrition important for MV pt's?
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malnutrition alters a pt's ability to effectively respond to infection, impairs wond healing, and severely reduces the ability to maintain spontaneous ventilation from weakened muscles.
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Train of Four (TOF)
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two electrodes are placed on the skin along a nerve path, often near a hand, foot, or facial nerve.
An electrical current cosisting of four impulses is applied to the peripheral nerve over 2 sec. and the muscle twitches produced provide information about the level of paralysis |
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RM consists of 3 maneuvers
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inflation
deflation another inflation RM |
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Best drug for MV?
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lorazepam (ativan) >24hrs
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Amnesics
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propofol
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