View as “PDF version”
Patient Safety Tip
of the Week
June
28, 2022
Pneumonia
in Nervous System Injuries
Last
week we focused on prevention of post-op pneumonia (see our June 21, 2022 Patient
Safety Tip of the Week “Preventing Post-op Pneumonia”). But another form of hospital-acquired
pneumonia that is even more frequent is that which is seen in patients admitted
with a variety of neurological conditions. So, timely is a recent review
article on pneumonia in nervous system injuries (Erfani 2022). Pneumonia is a significant contributor to
mortality and prolonged lengths of stay in patients with neurological
conditions.
Erfani and colleagues conducted an extensive literature search
and review on the topic. They note that over a third of patients admitted to neurointensive care units (neuro-ICUs) for a period
exceeding 48 hours develop nosocomial infections with pneumonia being the most
common type of infection. Ventilator-associated pneumonia is frequent in those
patients.
But
pneumonia also occurs frequently as a complication in neurological patients not
on ventilators or in neuro-ICU’s.
They
identify risk factors for hospital-acquired pneumonia (HAP) in general: Glasgow
Coma Scale (GCS) less than 8, mechanical ventilation, impaired airway reflexes,
supine positioning, aspiration, preexisting diseases like chronic obstructive
pulmonary disease (COPD), burns, prolonged ICU stay, use of positive end
expiratory pressure (PEEP) during mechanical ventilation, high disease
severity, multiple organ dysfunction, older age, prior administration of
antibiotics, malnutrition, use of the nasogastric tube, use of paralytic
agents, male gender, enteral feeding, immunosuppression, and trauma.
But
they note that the nature of the critical conditions in CNS leads to
higher susceptibility to developing pneumonia, due to factors such as brain injury-induced
immune dysregulation and immunosuppression, high prevalence of dysphagia, and interventions
such as placement of external ventricular drains (EVDs).
We have always focused on dysphagia and impairment of consciousness,
with consequent aspiration, as the major mechanism for pneumonia in
neurological inpatients. However, Erfani and colleagues point out some interesting contributing factors
that we had not been aware of. One such contributing factor is brain
injury-induced immune dysregulation. That is caused primarily caused by an
elevated inflammatory response which leads to central and peripheral production
of chemokines, proinflammatory cytokines, and cell adhesion molecules in these
patients. Development of the inflammatory response is a crucial part of
clearing cellular debris in the CNS following an injury. But chronic and
prolonged inflammation response can lead to dysregulation in the immune system.
Such is commonly seen in acute events, like trauma, brain surgery, subarachnoid
hemorrhage (SAH), or spinal cord injury. When it occurs after stroke, it is
named stroke-induced immunodepression syndrome (SIDS). SIDS is
considered to be biphasic, the first phase starting as soon as 12 hours
after the initial injury with early transient activation lasting up to 24
hours, and a second phase consisting of a systemic immunodepression that can
last for several weeks. They also discuss the immunosuppression that may occur
due to prolonged catecholamine release which accompanies many of these
conditions.
They
go on to discuss pneumonia in a variety of neurological conditions.
Known
risk factors for stroke-associated pneumonia (SAP) include dysphagia, higher
National Institutes of Health Stroke Scale (NIHSS), non-lacunar basal-ganglia
infarction, age, large middle cerebral artery (MCA) infarction, multiple
hemispheric or vertebrobasilar infarction, mechanical ventilation on admission,
and impaired vigilance. The presence of intubation also increases the risk of
pneumonia independently of the presence of known aspiration. Conversely, a
lower risk of SAP was seen in small-vessel occlusions (We, however, would
remind all that bilateral lacunar infarcts, which we often refer to as the “double
whammy” syndrome, may lead to pseudobulbar palsy that increases the risk of aspiration).
They also note that brain injury-induced immunosuppression may be more common
with more massive strokes and strokes impacting certain structures, such as the
insular cortex.
They,
of course, do go on to discuss dysphagia and impaired consciousness as major
factors contributing to development of pneumonia after stroke.
In
terms of pneumonia prevention, they do stress that addressing dysphagia is one
of the most important interventions. It is critical that, in patients with
stroke or the other mentioned neurological conditions, that an assessment of
swallowing be performed prior to giving food or anything via mouth. Improved
screening for dysphagia and nurse education has been shown to decrease the risk
of pneumonia as was demonstrated in a single-center study which showed a
decrease in pneumonia prevalence from 6.5% to 2.8% after the screening and
education changes were implemented.
Early
administration of prophylactic antibiotics has not been shown to be effective
in decreasing mortality or functional outcome in these patients and is not
indicated. They also note that oropharyngeal decontamination with
povidone-iodine has not been effective in the prevention of ventilator-associated
pneumonia (VAP) in patients with critical brain injuries or cerebral
hemorrhages.
.
The
timing of tracheostomy placement in such patients who require continuous
ventilation does not seem to affect the mortality rate but, in some studies,
early tracheostomy placement may decrease the duration of ventilation. (Note
that a just-published study (Bösel 2022) on the effect of early vs standard approach
to tracheostomy among patients with severe stroke receiving mechanical
ventilation showed no difference in the rate of survival without severe
disability at 6 months. In that study, pneumonia within 48 hours of tracheostomy
was more frequent in the early tracheostomy group but that did not reach
statistical significance. There
were no significant differences in the total duration of mechanical
ventilation or ICU length of stay.)
Erfani and colleagues also discuss another potential prevention
strategy: addressing brain injury-induced immunosuppression. Since this
immunosuppression is mainly due to sympathetic nervous system activation, they
discuss the potential use of β-adrenergic receptor blockers but caution
that further assessment of β-blocker administration needs to be carried
out in order for it to be confirmed as a routine
choice for the prevention of pneumonia in NICU’s.
In our June 2022 What's New in the Patient
Safety World column “Guideline Update: Preventing
Hospital-Acquired Pneumonia” we discussed the 2022 update of “Strategies
to prevent ventilator-associated pneumonia, ventilator-associated events, and nonventilator hospital-acquired pneumonia in acute-care
hospitals” (Klompas 2022). That update was collaborative work of the
Society for Healthcare Epidemiology (SHEA), the Infectious Diseases Society of
America (IDSA), the American Hospital Association, the Association for
Professionals in Infection Control and Epidemiology, and The Joint Commission,
with input from multiple other organizations and societies.
That
update included a new section on prevention of nonventilator
hospital-acquired pneumonia (NV-HAP). That section notes there is actually a scant evidence base for strategies to prevent
NV-HAP. This section emphasizes oral care, recognizing and managing dysphagia,
early mobilization, and implementing multimodal approaches to prevent viral
infections. Regarding diagnosis and management of dysphagia, the updated
guideline had the following recommendations:
1.
Early diagnosis and treatment of dysphagia may
prevent NV-HAP, especially among neurologically impaired post-stroke patients.
2.
Potential approaches to diagnose dysphagia
include nurse-administered risk assessment tools, bedside functional
evaluations of swallowing, video fluoroscopic study, and fiberoptic endoscopic
examination.
3.
Potential options to manage dysphagia include
changes in method of pill administration, adjustments in consistencies of
liquids and solids, supervision or assistance with meals, use of straws, and
elevation of the head of bed while eating.
One
surprising omission from the discussion of pneumonia in neurological conditions
is OSA (obstructive sleep apnea). We know that OSA is common in acute stroke
patients and some of the other conditions, and that OSA has been linked as a
possible contributing factor to community-acquired pneumonia (Chiner 2016). It would certainly be of interest to see
if OSA is a risk factor for development of pneumonia in these and other
inpatient conditions.
For
those that are interested, the Erfani review also
discusses pneumonia is subarachnoid hemorrhage, brain traumatic injury, intracerebral
hemorrhage, spinal cord injury, status epilepticus, neuromuscular diseases, and
multiple sclerosis (MS) and demyelinating diseases. It also has sections on
radiographic findings and treatment of pneumonia. The Erfani
review has 139 references with links. We think you will find this very useful.
References:
Erfani Z, Jelodari Mamaghani H, Rawling J, et al. Pneumonia in Nervous System
Injuries: An Analytic Review of Literature and Recommendations. Cureus 2022; 14(6): e25616
Bösel J, Niesen W, Salih F, et
al. Effect of Early vs Standard Approach to Tracheostomy on Functional Outcome
at 6 Months Among Patients With Severe Stroke
Receiving Mechanical Ventilation: The
SETPOINT2 Randomized Clinical Trial. JAMA 2022; 327(19): 1899-1909
https://jamanetwork.com/journals/jama/article-abstract/2792016
Klompas
M, Branson R, Cawcutt K, et al..
Strategies to prevent ventilator-associated pneumonia, ventilator-associated
events, and nonventilator hospital-acquired pneumonia in
acute-care hospitals: 2022 Update. Infect Control Hosp Epidemiol 2022; 20: 1-27
Chiner E, Llombart M, Valls
J, et al. Association between Obstructive Sleep Apnea and
Community-Acquired Pneumonia. PloS One 2016; 11(4): e0152749
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4822965/
Print
“PDF
version”
|
|
http://www.patientsafetysolutions.com/