1. Identify the neuromuscular blocking agent that is associated with malignant hyperthermia.2. Identify the negative outcome that can result from relying only on clinical features that do not include sputum culture to diagnose VAP.3. List causes and risk factors for VAP.4. Describe the pathogenesis of VAP.5. List clinical findings seen with VAP.6. Identify the most common organism type seen in VAP.7. Identify the incidence of VAP for all intubated patients.8. Identify the common bacteria seen in the upper airway of healthy people.9. Identify the clinical lab study that contributes the most toward the effective treatment of VAP.10. List commonly used benzodiazepines in the ICU.11. Identify time required for the onset of symptoms for a respiratory infection to be considered VAP.12. Identify the most useful feature of dexmedetomidine (Etomidate) in the ICU.13. List items typically included in a ventilator bundle.14. Identify the mortality rate for VAP.15. List items included in the updated definition of VAP.16. List interventions that may reduce the risk of VAP.17. Differentiate features of mild, moderate and deep sedation.18. Identify the medication type that may be useful in a case where patient-ventilator asynchrony cannot be corrected.
Ventilator-Associated Pneumonia
RCP 3011, Mechanical Ventilation
w/Lab
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
1
Ventilator-Associated Pneumonia
Hospital-Acquired Pneumonia
Health Care–Associated Pneumonia
?
VAP
? Develops 48 hours after the patient has been
placed on mechanical ventilation
?
HAP
? Occurs 48 hours or longer after admission to the
hospital
? Results from infection not incubating at the time of
admission
?
HCAP
? Affects patients residing in long-term or acute care
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
2
Ventilator-Associated Pneumonia
?
Most often is caused by bacterial infections
? Can be fungal infections, or viral epidemics (e.g.,
severe acute respiratory syndrome [SARS])
? Early onset pneumonia: 48 to 72 hours after
tracheal intubation
? Late onset pneumonia: Later than 72 hours
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
3
Epidemiology
?
VAP is the most common HAP infection in the
intensive care unit (ICU)
? Risk: 3% per day during the first 5 days, 2% per
day during 5 to 10 days, 1% thereafter
? Incidence: 8% to 28% for all intubated patients
? Mortality: 5% to 48%, depending on the infecting
organism, the presence of underlying disease, and
prior antimicrobial therapy
? Prognosis: early onset—antibiotic-sensitive
bacteria; late onset—MDR pathogens
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
4
Causes and Risk Factors
?
Linked to:
? The aspiration of oropharyngeal secretions and
esophageal/gastric contents
? Direct inoculation of infectious material into the trachea and
lungs during endotracheal intubation
? Inhalation of infected aerosols
? Embolization of biofilm that can be found in the endotracheal
tubes (ETs) of patients receiving prolonged mechanical
ventilation
? Exogenous penetration from the pleural space
? The blood-borne spread of extrapulmonary infections to the
lung
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
5
Methods to Reduce the Risk of
Nosocomial Pneumonias in Mechanically
Ventilated Patients
?
Pharmacologic:
? Concurrent steroid therapy
? Inappropriate antimicrobial therapy
? Overuse of sedatives and paralytics
? Use of type 2 (H2) histamine antagonists and
gastroprotective agents (e.g., antacids)
? MDRs
?
Nonpharmacologic:
? Need for endotracheal tube (ET) or tracheostomy tube
during ventilation
? Routine care of ventilator circuits, humidifiers, nebulizers
? Use of respirometers, reusable electronic ventilator probes
and sensors, bronchoscopes, endoscopes
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
6
Pathogenesis of VAP (1 of 3)
The upper airways of healthy individuals
typically contain nonpathogenic bacteria,
such as the viridans group of streptococci,
Haemophilus spp., and anaerobes
? Aerobic gram-negative bacilli, most notably
virulent forms of P. aeruginosa and
Acinetobacter, are rarely found in the
respiratory tract of healthy individuals
because of anatomic barriers
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
7
Pathogenesis of VAP (2 of 3)
?
The pathogenesis of VAP most often
involves:
? Colonization of aerodigestive tract with pathogenic
bacteria
? Aspiration of contaminated secretions into the
lower airways
? Colonization of the normally sterile lower airways
and lung parenchyma with infectious
microorganisms
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
8
Pathogenesis of VAP (3 of 3)
During critical illnesses, particularly in
patients with an endotracheal tube and
receiving mechanical ventilation, there is a
dramatic shift in the flora of the
oropharyngeal tract to gram-negative bacilli
and S. aureus
? Aspiration of the contaminated oropharyngeal
secretions and, in some cases,
gastroesophageal contents can occur
because the patient is unable to protect the
lower airways
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
9
Diagnosis of VAP (1 of 4)
Lack of a precise definition for the diagnosis
of VAP
? Simply relying on clinical findings to guide
therapeutic interventions can be subjective
?
? This can result in a failure to accurately diagnose
VAP
? Leads to inappropriate antibiotic therapy if the
infection is polymicrobial in origin or if a drugresistant organism is present
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
10
Diagnosis of VAP (2 of 4)
?
In 2011, the Centers for Disease Control
(CDC) and National Healthcare Safety
Network (NHSN) proposed an updated
definition
? Incorporates the general features of the ATS/IDSA
definition
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
11
Diagnosis of VAP (3 of 4)
CDC surveillance definition uses the term
ventilator-associated event (VAE) to describe
a range of conditions and complications that
occur in mechanically ventilated patients,
including VAP
? VAEs can be categorized as:
?
? A ventilator-associated condition (VAC)
? An infection-related ventilator-associated
complication (IVAC)
? Possible pneumonia or probable pneumonia
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
12
Diagnosis of VAP (4 of 4)
?
To diagnose the presence of pneumonia in
ventilated patients the CDC surveillance
definition relies on the use of:
? Only objective data
? Clearly defined time criteria
? The exclusion of radiographic imaging
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
13
Clinical Diagnosis
?
Should be suspected when a mechanically ventilated
patient demonstrates radiographic evidence of new
or progressive infiltrates and one or more of the
following findings:
? Fever
? Leukocytosis
? Purulent tracheobronchial secretions
? Decreased oxygenation
? Increased minute ventilation
? A decrease in tidal volume
? An increase in respiratory rate
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
14
Clinical Pulmonary Infection Score
(CPIS)
A “weighted” approach to clinical diagnosis
? Includes six clinical assessments with each item
given a score of 0 to 2 points
? Includes:
?
? Fever, leukocyte count, quantity and purulence of tracheal
secretions, oxygenation status, the type of radiographic
abnormality, and results of a tracheal aspirate culture and
Gram stain
?
A score greater than 6 is considered evidence of the
presence of VAP
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
15
Bacteriologic (Quantitative)
Diagnosis (1 of 2)
?
Obtaining quantitative cultures of specimens
from lower respiratory tract:
? Uses fiber-optic bronchoscopy
? Uses non-bronchoscopic techniques
• Mini bronchoalveolar lavage (BAL)
• Blinded bronchial sampling (BBS)
• Blinded sampling with protected-specimen brush (BPSB)
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
16
Bacteriologic (Quantitative)
Diagnosis (2 od 2)
?
Bacteriologic studies include:
? Quantitative culture techniques
? Microscopic analysis of the cultures using an
appropriate stain
?
Direct microscopic and histologic
examinations of BAL and PBS samples can
be used to identify the presence or absence
of bacteria in the lower respiratory tract
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
17
Treatment of VAP
Initiating empiric antibiotic therapy
? The ATS-IDSA Guidelines for the
Management of Adults with HAP, VAP, and
HCAP
?
? Provide a series of pathways to guide clinicians on
the initiation of empiric antibiotic therapy, as well
as strategies that can be used to reduce the
emergence of MDR pathogens
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
18
Strategies to Prevent VAP
?
Establishment of well-designed infectioncontrol practices in the ICU
? Recognize that it is a high-priority task
Adequate physical and human resources
must be provided to establish surveillance
mechanisms to track the local incidence of
VAP and other nosocomial infections
? Incorporated into ventilator bundles
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
19
Prevention: Nonpharmacologic
(1 of 3)
Noninvasive ventilation
? Hand washing and the use of accepted infection
control procedures and practices
? Semirecumbent positioning of the patient
? Enteral feeding
? Appropriate circuit changes when grossly
contaminated
? Heat-moisture exchanges when possible
? Aspiration of subglottic secretions
? Appropriate disinfection and sterilization techniques
? Kinetic beds
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
20
Prevention:
Nonpharmacologic (2 of 3)
Identifying a dedicated person or group for monitoring
nosocomial VAP rates
? Using closed suction catheters and sterile suction
technique
? Avoiding large gastric volumes
? Extubating and removing nasogastric tube as
clinically indicated
? Avoiding contamination with ventilator circuit
condensate
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
21
Prevention:
Nonpharmacologic (3 of 3)
Using single-patient items such as monitors, oxygen
analyzers, and resuscitation bags
? Carefully using in-line, small-volume nebulizers
? Considering the use of expiratory-line gas traps or
filters
? Using oral rather than nasal intubation
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
22
Prevention: Pharmacologic
Oral decontamination
? Stress ulcer prophylaxis
? Selective digestive tract decontamination
? Prophylactic antibiotics
? Sedation interruption and daily assessment of
readiness for endotracheal extubation
?
Copyright © 2020 by Elsevier, Inc. All Rights Reserved.
23
Sedatives, Analgesics,
and Paralytics
RCP 3011, Mechanical Ventilation
w/Lab
Copyright © 2020 by Elsevier, Inc. All rights reserved.
1
Pharmacologic Agents (1 of 2)
Sedatives are used to reduce anxiety and
agitation and to promote sleep and
anterograde amnesia
? Analgesics are used to lessen pain
? Paralytics are used to facilitate invasive
procedures (e.g., surgery, endotracheal
intubation) and to prevent movement and
ensure the stability of artificial airways
?
Copyright © 2020 by Elsevier, Inc. All rights reserved.
2
Pharmacologic Agents (2 of 2)
?
Most common in the ICU:
? (1) Benzodiazepines (e.g., diazepam, midazolam,
and lorazepam)
? (2) Neuroleptics (e.g., haloperidol)
? (3) General Anesthetic agents (e.g., propofol)
? (4) Opioids (e.g., morphine, fentanyl)
?
Neuromuscular blocking agents (NMBA)
? Depolarizing NMBA (succinylcholine)
? Nondepolarizing NMBAs (pancuronium,
vecuronium, and atracurium)
Copyright © 2020 by Elsevier, Inc. All rights reserved.
3
Sedatives and Analgesics (1 of 3)
?
Four levels of sedation:
? Minimal
• Patients can respond to verbal commands,
although cognitive function may be impaired
• Ventilatory and cardiovascular functions are
unaffected
? Moderate (conscious sedation)
• The patient can perform purposeful response
following repeated or painful stimulation
• Spontaneous ventilation is adequate, and
cardiovascular function is usually maintained
Copyright © 2020 by Elsevier, Inc. All rights reserved.
4
Sedatives and Analgesics (2 of 3)
?
Four levels of sedation:
? Deep
• The patient is not easily aroused but can
respond to painful stimulation
• Spontaneous ventilation and maintenance of
patent airway may be inadequate
• Cardiovascular function is usually maintained
Copyright © 2020 by Elsevier, Inc. All rights reserved.
5
Sedatives and Analgesics (3 of 3)
?
Four levels of sedation:
? Anesthesia
• Involves general anesthesia, spinal, or major
regional anesthesia; local anesthesia is not
included
• Patient cannot be aroused, even by painful
stimulation
• Ventilatory assistance is typically required (i.e.,
artificial airway and positive-pressure
ventilation)
• Cardiovascular function may be impaired
Copyright © 2020 by Elsevier, Inc. All rights reserved.
6
Monitoring the Need for Sedation
and Analgesia (1 of 2)
?
Ramsay Sedation Scale (RSS)
? Advantages:
• A graduated single-category scale
• The grade assigned by the observer depends on the
patient’s response to stimuli
• A score of 2 to 4 indicates adequate sedation
? Disadvantages:
• Does not provide any guidance on selection of the most
appropriate sedative
• It is a subjective, nonlinear scale that does not allow for
consideration of changing physiological and
psychological needs of a patient during the course of his
or her illness
Copyright © 2020 by Elsevier, Inc. All rights reserved.
7
Monitoring the Need for Sedation
and Analgesia (2 of 2)
Motor Activity Assessment Scale (MAAS)
? Sedation-Agitation Scale (SAS)
? Comfort Scale
?
Copyright © 2020 by Elsevier, Inc. All rights reserved.
8
Types of Sedatives and Analgesics
(1 of 6)
?
Benzodiazepines
• Interact with GABA receptor complex on neurons in the
brain
? Diazepam (Valium)
• Rapid onset of action because of its high lipid solubility
and ability to traverse the blood-brain barrier relatively
quickly
? Midazolam (Versed)
• Rapid onset of action and short half-life, making it an
ideal sedative for the treatment of acutely agitated
patients
? Lorazepam (Ativan)
• Drug of choice for sedating mechanically ventilated
patients in the ICU for longer than 24 hours
Copyright © 2020 by Elsevier, Inc. All rights reserved.
9
Types of Sedatives and Analgesics
(2 of 6)
?
?2-adrenoreceptor agonist dexmedetomidine
? Dexmedetomidine (Etomidate)
? Used for short-term sedation and analgesia in the
ICU.
? Does not affect respiratory or cardiovascular
systems
?
Neuroleptics
? Haloperidol (Haldol)
• Used to treat patients demonstrating evidence
of extreme agitation and delirium
Copyright © 2020 by Elsevier, Inc. All rights reserved.
10
Types of Sedatives and Analgesics
(3 of 6)
?
Anesthetic agents
? Propofol (Diprivan)
• Sedative, amnesic, and hypnotic properties at
low doses
• Causes reductions in systemic vascular
resistance with a concomitant fall in blood
pressure and bradycardia during the initial
induction phase
• Prolonged use (longer than 48 hours) in
pediatric patients has been associated with the
development of lactic acidosis
Copyright © 2020 by Elsevier, Inc. All rights reserved.
11
Types of Sedatives and Analgesics
( 4 of 6)
?
Opioids
? Morphine
• Preferred agent for intermittent therapy
because of its longer duration of action
• Can cause apnea
? Fentanyl (Sublimaze)
• A synthetic opioid that is approximately 100 to
150 times more potent than morphine
• Rapid onset of action
• Longer half-life than morphine
• Preferred for patients with hemodynamic
instability and renal insufficiency
Copyright © 2020 by Elsevier, Inc. All rights reserved.
12
Types of Sedatives and Analgesics
(5 of 6)
?
Paralytic agents
? Depolarizing agents (succinylcholine “sux”)
resemble acetylcholine in their chemical structure
• Can precipitate malignant hyperthermia in
susceptible individuals
? Nondepolarizing agents (pancuronium,
vecuronium, atracurium, cisatracurium) also bind
to acetylcholine receptors but cause paralysis by
competitively inhibiting the action of acetylcholine
at the neuromuscular junction
Copyright © 2020 by Elsevier, Inc. All rights reserved.
13
Types of Sedatives and Analgesics
(6 of 6)
?
Choosing the most appropriate muscle
relaxant depends on:
? Its onset of action
? How fast the patient can recover from its effects
once it is discontinued
? The patient’s physical condition and organ
function (particularly renal and hepatic function)
? The pharmacodynamics and cost of the drug
Copyright © 2020 by Elsevier, Inc. All rights reserved.
14
Monitoring Neuromuscular Blockade
Accomplished using visual, tactile, and electronic
assessment of the patient’s muscle tone
? Train-of-four (TOF) monitoring
? Two electrodes are placed on the skin along a
nerve path, often near a hand, foot, or facial nerve
? Muscle contractions (twitches) produced provide
information about the level of paralysis
? Society for Critical Care Medicine (SCCM)
recommends that one to two twitches indicate that
an adequate amount of NMBA is being
administered
?
Copyright © 2020 by Elsevier, Inc. All rights reserved.
15
Next Week . . .
?
Open Lab
Copyright © 2020 by Elsevier, Inc. All rights reserved.
16
Troubleshooting and
Problem Solving
RCP 3011, Mechanical Ventilation
Define the “Problem”
?
A situation in which a person finds discord or
is uncomfortable with a matter that cannot be
immediately resolved
? Subjective
? Personal perspective
? Solving ventilation problems
? Protecting the patient
Define the “Problem”—cont’d
?
Troubleshooting
using ventilator
graphics
Solving Ventilation Problems
First, assess the situation at hand carefully
? Next, gather and analyze pertinent data
? Clinician’s observations of the patient’s
response are critical
? Determining the cause of the problem can
help prevent its recurrence
?
Protecting the Patient
Ensuring patient safety is the foremost
obligation of the clinician
? Whenever an alarm activates on a ventilator
or monitoring device, the clinician should:
?
? First make sure that the patient is adequately
ventilated and oxygenated
? During this initial assessment, the alarm should be
checked and silenced
? When a serious problem is detected, the patient
may need to be disconnected from the ventilator
and manually ventilated with a resuscitation bag
Protecting the Patient—cont’d
?
Removing a patient from the ventilator for
manual ventilation can:
? Inadvertently cause barotrauma by using
excessive pressure during manual ventilation (>40
cm H2O)
? If patient is mechanically ventilated with a high
level of PEEP, can cause derecruitment of the
lung
? Cause contamination of the patient’s airway,
increasing the patient’s risk of developing
ventilator-associated pneumonia
Management of Sudden Severe Distress
Disconnect the patient from the ventilator
? Begin manual ventilation with a BVM
? Tactile assessment of CL and RAW.
? Perform rapid physical evaluation
? Check airway patency with a suction catheter
? If death appears eminent, treat most likely
problems
?
? Pneumothorax
? Airway obstruction
?
Once stabilized, perform more comprehensive
evaluation
Patient-Related Problems
?
Airway problems
? Pneumothorax
? Bronchospasm
? Secretions
? Pulmonary edema
? Dynamic
hyperinflation
? Respiratory drive
abnormalities
? Change in body
position
? Drug-induced
distress
? Abdominal distention
? Pulmonary embolism
Patient-Related Problems—cont’d
?
The most common patient-related problems
encountered during mechanical ventilation
involve:
? The placement and patency of the artificial airway
? The presence of a pneumothorax, bronchospasm,
and excessive secretions
Emergency Treatment for Rupture of
the Innominate Artery
Usually is seen in the first 3 weeks after a
tracheostomy; mortality rate for this condition is high
? Immediate indication is blood spurting from the
tracheotomy site
? To stop the hemorrhage:
?
? The cuff should be overinflated or pressure should be
applied internally with a finger inserted through the stoma
? The finger is inserted as far as possible toward the carina
and then pulled forward in an attempt to compress the artery
against the posterior aspect of the sternum
Ventilator-Related Problems
Leaks
? Inadequate oxygenation
? Inadequate ventilatory support
? Trigger sensitivity
? Inadequate flow setting
? Patient-ventilator asynchrony
?
? Clinician should disconnect the patient from the
ventilator and carefully ventilate the patient using
a manual resuscitation bag
Ventilator-Related
Problems—cont’d
?
Trigger asynchrony
? Confirm that the sensitivity level has been set
appropriately, that air trapping (auto-PEEP) is not
present, and that the patient is not agitated
?
Flow asynchrony
? Ensure the flow is adequate and the flow delivery
curve is appropriate
?
Cycle asynchrony
? With PSV, ensure that the patient is not exhaling
actively; with PC-CMV, make sure the duration set
for the TI is not too long
Ventilator-Related
Problems—cont’d
?
Mode asynchrony
? Occurs when more than one type of breath is
delivered, such as with IMV; another mode may
be more appropriate for the patient
?
PEEP asynchrony
? Causes include overdistention from excess PEEP
and atelectasis and atelectrauma from a PEEP
setting that is too low; make sure PEEP is set at
an appropriate level
Ventilator-Related
Problems—cont’d
?
Closed loop ventilation asynchrony
? Closed loop mode may not be performing as
needed for a particular patient
? Make sure current settings are appropriate
? Consider selecting another mode
Ventilator-Related
Problems—cont’d
Common Alarm Situations
Low-pressure alarm
? High-pressure alarm
? Low PEEP/CPAP
alarm
? Apnea alarm
? Low-source gas
pressure or power
input alarm
?
Common Alarm
Situations—cont’d
Ventilator inoperative alarm and technical
error message
? Operator settings incompatible with machine
parameters
? Inspiratory-to-expiratory (I:E) ratio indicator
and alarm
? Other
?
Using Graphics
?
Leaks
Using Graphics—cont’d
?
Leaks
Using Graphics—cont’d
?
Auto-PEEP
Using Graphics—cont’d
• Airway Secretions
Using Graphics—cont’d
?
Asynchronyy
Alarm Response
Hear the alarm
? Start assessment before entering the room
? Look:
?
? The patient
? The monitor
? The ventilator display
Use all of your senses
? Silence alarm (stressful for all in room)
?
Alarm Response (cont.)
Easy fix? Do it.
? Not obvious? Next step
? Start at the patient and work toward ventilator
? Distress? No: You have time / Yes: Bagging
decision
? Decide if you need help:
?
? Immediate
? Another RT
Next Week
?
VAP, Paralytics & Sedatives
Discontinuation of
Mechanical Ventilation
RCP 3011, Mechanical Ventilation
Introduction
?
Ventilatory support sustains life but is not curative.
?
It has many complications and hazards.
?
It should be withdrawn rapidly.
?
Balance desire for early extubation with its exposure to the
risks of reintubation.
Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc.
2
Methods of Discontinuing
Ventilation
?
Three main methods
? Spontaneous breathing trials (SBT)
• With or without PSV
? SIMV
?
Newer modes with no data to support their use
• MMV = mandatory minute volume, VSV = volume support ventilation, ATC =
automatic tube compensation, PAV = proportional assist ventilation
**Systematic review: 1 SBT per day has shown best results**
Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc.
3
Discontinuing Ventilatory Support
?
Success is tied to:
? Ventilatory work load versus capacity
? Oxygenation status
? Cardiovascular status
? Nutritional factors
? Psychological factors
Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc.
4
Most Important Criteria
1.
At least partial reversal of disease state that
necessitated ventilatory support
2.
Oxygenation status adequate on FiO2