Feature
Head-of-Bed Elevation
in Critically Ill Patients:
A Review
Norma A. Metheny, RN, PhD
Rita A. Frantz, RN, PhD
Clinicians are confused by conflicting guidelines about the use of head-of-bed elevation to prevent aspiration and
pressure ulcers in critically ill patients. Research-based information in support of guidelines for head-of-bed elevation to prevent either condition is limited. However, positioning of the head of the bed has been studied more
extensively for the prevention of aspiration than for the prevention of pressure ulcers, especially in critically ill
patients. More research on pressure ulcers has been conducted in healthy persons or residents of nursing homes
than in critically ill patients. Thus, the optimal elevation for the head of the bed to balance the risks for aspiration and pressure ulcers in critically ill patients who are receiving mechanical ventilation and tube feedings is
unknown. Currently available information provides some indications of how to position patients; however, randomized controlled trials where both outcomes are evaluated simultaneously at various head-of-bed positions
are needed. (Critical Care Nurse. 2013;33[3]:53-67)
G
uidelines for head-of-bed (HOB) elevation to prevent aspiration and pressure ulcers are
in conflict. As indicated in Table 1, several expert sources recommend a 45º HOB elevation
(unless medically contraindicated) to prevent aspiration1-3 while others recommend an HOB
elevation between 30º and 45º (again, unless medically contraindicated).4-10 In contrast, pressure ulcer
guidelines call for raising the HOB no more than 30º to avoid excessive pressure on the sacral region.11-13
Although the recommendations overlap, a 45º HOB elevation is generally favored to prevent aspiration
in critically ill patients who are receiving mechanical ventilation and tube feedings.1,14 Because aspiration
is a threat to oxygenation, some authors caution that aspiration is a greater and more immediate concern
than are pressure ulcers in critically ill patients.15 Clearly, the conflicting guidelines regarding aspiration
and pressure ulcers are problematic for critical care clinicians who strive to prevent the suffering and
increased costs associated with both conditions.16
CNE Continuing Nursing Education
This article has been designated for CNE credit. A closed-book, multiple-choice examination follows this article, which
tests your knowledge of the following objectives:
1. Discuss guidelines for head-of-bed (HOB) elevation to prevent aspiration and pressure ulcers
2. Distinguish relevant studies recommending HOB elevation to prevent aspiration and aspiration-related conditions
3. Critique studies relevant to HOB elevation for pressure ulcer prevention
©2013 American Association of Critical-Care Nurses doi: http://dx.doi.org/10.4037/ccn2013456
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Vol 33, No. 3, JUNE 2013
53
Table 1
Summary of guidelines for head-of-bed elevation
Guidelines to prevent
pressure ulcers
Guidelines to prevent aspiration/pneumonia
Elevate head of bed to 45º, unless contraindicated
• Canadian clinical practice guidelines for nutrition support in mechanically ventilated, critically
ill adult patients. Journal of Parenteral and Enteral Nutrition, 20031
• Prevention of ventilator-associated pneumonia: an evidence-based systematic review.
Annals of Internal Medicine, 20032
• Comprehensive evidence-based clinical practice guidelines for ventilator-associated pneumonia:
diagnosis and treatment. Journal of Critical Care, 20083
Elevate head of bed from 30º to 45º, unless contraindicated
• Guidelines for the provision and assessment of nutrition support therapy in the adult critically
ill patient: Society of Critical Care Medicine and American Society for Parenteral and Enteral
Nutrition. Journal of Parenteral and Enteral Nutrition, 20094
• Enteral nutrition practice recommendations. American Society for Parenteral & Enteral
Nutrition. Journal of Parenteral and Enteral Nutrition 20095
Raise head of bed no more than 30º
(and preferably less)
• Prevention and Treatment of Pressure
Ulcers: Clinical Practice Guideline.
Washington, DC: National Pressure
Ulcer Advisory Panel (NPUAP); 200911
• Guideline for Prevention and Management of Pressure Ulcers. 2010 June 1.
96 p. (Wound Ostomy and Continence
Nurses Association clinical practice
guideline; no. 2)12
• Guidelines for the prevention of
pressure ulcers. Wound Healing
Society, Wound Repair and Regeneration, 2008 13
• North American summit on aspiration in the critically ill patient: consensus statement,
American Society for Parenteral and Enteral Nutrition. Journal of Parenteral and Enteral
Nutrition, 20026
• American Gastroenterological Association technical review on tube feeding for enteral
nutrition. Gastroenterology, 19957
• Guidelines for preventing health-care–associated pneumonia, 2003: recommendations of
CDC and Healthcare Infection Control Practices Advisory Committee. Morbidity and Mortality Weekly Report, 20048
• Practice Alert: Ventilator-Associated Pneumonia. American Association of Critical-Care
Nurses, 20089
• Practice Alert: Prevention of Aspiration. American Association of Critical-Care Nurses, 201110
Aspiration of gastric contents is a primary route of
bacterial entry into the lungs and is an important factor in
the development of ventilator-associated pneumonia (VAP).
VAP is the most common nosocomial infection in critically
ill patients and is an important cause of prolonged hospitalization and mortality.17 For example, a review of 89 observational and randomized trials regarding VAP showed that
VAP developed in between 10% and 20% of patients receiving
more than 48 hours of mechanical ventilation, and critically
ill patients in whom VAP develops appear to be twice as
likely to die as similar patients without VAP.18 Further,
patients in whom VAP develops may incur at least $10019
in additional hospital costs.18 Because VAP prevention is
partially predicated on the prevention of aspiration, it is
understandable why guidelines for both aspiration and
VAP include an elevated HOB position.9,10 The Centers for
Medicare and Medicaid Services (CMS) is considering
adding VAP to the list of “never events”; if this happens,
punitive reimbursement policies could follow.19
Pressure ulcers are also associated with adverse outcomes and increased hospital costs.20 Fatalities from septicemia associated with untreated pressure ulcers are
occasionally reported.21 However, a pressure ulcer is often
a marker for coexisting illness and other risk factors for
mortality.22 Among all hospitalized patients, prevalence
rates of acquired pressure ulcers are highest in patients in
Authors
Norma A. Metheny is a professor and Dorothy A. Votsmier Endowed Chair at Saint Louis University School of Nursing, St Louis, Missouri.
Rita A. Frantz is Kelting Dean and professor at the University of Iowa College of Nursing in Iowa City.
Corresponding author: Norma A. Metheny, RN, PhD, FAAN, Saint Louis University School of Nursing, 3525 Caroline Mall, St. Louis, MO 63104 (e-mail: [email protected]).
To purchase electronic or print reprints, contact The InnoVision Group, 101 Columbia, Aliso Viejo, CA 92656. Phone, (800) 899-1712 or (949) 362-2050 (ext 532); fax, (949)
362-2049; e-mail, [email protected].
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intensive care units (ICUs). In 2009, approximately 1 in
10 patients in adult ICUs in the United States had a pressure ulcer develop.23 Facility-acquired pressure ulcer rates
were 8.8% in general cardiac care units, 9.4% in medical
ICUs, 10.3% in general ICUs, and 10.4% in surgical ICUs;
about 65% to 75% of the ulcers were more severe than
stage I.23 The cost of treating pressure ulcers, especially
stage III and IV ulcers, is substantial.24 The mean cost of
care for an acute care patient with a stage III or IV pressure ulcer is reported by the CMS to be $43180.25 In 2006,
the CMS added stage III and IV pressure ulcers to the list
of “never events.”26 Beginning in 2008, the CMS refused
to pay for the care of a hospital-acquired pressure ulcer in
stages III and IV unless it was determined to have been
unavoidable. One component of the pressure ulcer guidelines issued by the National Pressure Ulcer Advisory Panel
is a low HOB elevation (preferably <30º).11
Pathophysiology of Aspiration
Aspiration is defined as the inhalation of oropharyngeal secretions or gastric contents into the airways
beyond the vocal cords. Consequences of pulmonary aspiration depend on the volume and chemical composition
of the aspirated material as well as on the presence or
absence of infectious agents and the patient’s underlying
condition. The associated lung injury is characterized by
pulmonary inflammation, capillary leakage, and oxidative
damage. Variable outcomes are possible, ranging from
mild pneumonitis to acute respiratory distress and death.
Risk factors for pulmonary aspiration include conditions
that depress the level of consciousness, a decreased gag
reflex, tracheal intubation, presence of a gastric tube, and
a full stomach. Critically ill patients undergoing mechanical ventilation who are receiving tube feedings are at especially high risk for the aspiration of regurgitated gastric
contents. Reports of witnessed macroaspirations in critically ill patients range from less than 1% to 11.7%27; far
more common are clinically silent, small-volume aspirations. For example, McClave et al28 reported a 22.1% mean
frequency of clinically silent microaspirations per patient
(range, 0%-94%) in a group of 40 adult critically ill, tubefed patients receiving mechanical ventilation.
Pathophysiology of Pressure Ulcers
The National Pressure Ulcer Advisory Panel has defined
a pressure ulcer as localized injury of the skin and/or underlying tissue, usually over a bony prominence, as a result of
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pressure or pressure in combination with shearing force.11
Oxygen delivery to the skin is compromised when it is
exposed to a pressure greater than the capillary closing
pressure; if sustained, tissue necrosis results. An elevated
HOB position results in an increased interface pressure
between the sacrum and the bed’s surface; in addition,
potential for injury of skin in the sacral region is increased
when the HOB is elevated sufficiently to cause the patient to
slide downward. The bony prominence most affected by
pressure ulcers is the sacrum.29 For patients turned on
their sides at regular intervals, damage of skin over the
trochanters may occur (although it is unlikely when patients
are turned to an angle ≤30º). Healing rates of pressure
ulcers vary considerably and are dependent on comorbid
conditions, clinical interventions, and severity of the ulcer.
Purpose
In this article, we review guidelines for HOB elevation
to prevent aspiration and pressure ulcers, as well as the
limited research-based information in support of the
guidelines. Table 2 lists studies relevant to HOB elevation
and aspiration30-37 (as well as aspiration-related conditions),
and Table 3 lists studies relevant to HOB elevation and
pressure ulcers.38-44
Evidence to Support HOB Elevation to
Prevent Aspiration
Much of the supportive evidence for a semirecumbent
position to prevent aspiration was gathered several decades
ago in studies with relatively small sample sizes. In randomized trials of critically ill patients, investigators compared the
effect of a
Increased compliance with keeping the HOB
supine (0º
elevated ≥30° led to a decrease in rates of
HOB eleventilator-associated pneumonia.
vated position) versus a 45º HOB elevated position on aspiration by
adding a radioactive substance to gastric contents and
subsequently scanning bronchial secretions for radioactivity.30,31 This method for testing for aspiration is highly
reliable and demonstrates the extent to which HOB elevation is associated with aspiration. In another frequently
cited and credible study,33 researchers assessed for microbiologically confirmed pneumonia when patients were
flat in bed versus at a 45º HOB elevation. Because of ethical concerns, it would be not be possible today to assign
critically ill patients to a supine position to study aspiration.
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Table 2
Studies related to head-of-bed (HOB) elevation and aspiration or aspiration-related pneumonia
Source
Sample
Design
Outcome
Torres et al,30 Annals of
Internal Medicine, 1992
19 patients with nasogastric tubes
undergoing mechanical ventilation
Mean age, 60 y
Randomized 2-period
cross-over study
Aspiration of gastric contents
Orozco-Levi et al,31 American
Journal of Respiratory and
Critical Care Medicine, 1995
15 patients with nasogastric tubes
undergoing mechanical ventilation
Mean age, 56 y
Randomized 2-period
cross-over study
Aspiration of gastric contents
Gastroesophageal reflux (GER)
Ibanez et al,32 Journal of Parenteral and Enteral Nutrition,
1992
70 orotracheally intubated patients
50 received enteral nutrition while
gastric contents labeled with
technetium Tc 99m
20 had nasogastric tubes removed after
instillation of technetium Tc 99m
Randomized 2-group study
GER
Drakulovic et al,33 Lancet, 1999
86 critically ill patients receiving mechanical
ventilation
47 supine, 39 semirecumbent
Enteral feedings used in 56%-60% of
patients
Mean age, 65 y
Randomized 2-group study
Microbiologically confirmed
nosocomial pneumonia
Metheny et al,34 Critical Care
Medicine, 2006
360 critically ill tube-fed patients undergoing
mechanical ventilation
Mean age, 52 y
Prospective descriptive study
Aspiration of gastric contents
Pneumonia
Method
Results
Randomly assigned to supine (0°) or 45° HOB elevation
during period 1 and other position during period 2
Technetium Tc 99m instilled into nasogastric tubes;
bronchial secretions collected at 0, 30, 60, 120, 180,
240, and 300 min and tested for radioactivity
(counts per minutes [cpm])
Samples of bronchial secretions, gastric juice, and
pharyngeal contents also obtained for qualitative
bacterial cultures
Mean radioactive counts higher in bronchial
samples obtained with patient supine vs
semirecumbent (4154 cpm vs 954 cpm,
respectively, P = .04).
Aspiration increased over time while patient
supine (2592 cpm at 300 min vs 298 cpm
at 30 min, P = .01)
Same microorganisms isolated from stomach,
pharynx, and bronchial samples in 68% of
studies when patients supine, as compared
with 32% when patients semirecumbent
45° HOB elevation associated with less
aspiration than supine position
Risk for aspiration increases over time
when patient is supine
Conclusions
Random assignment to supine (0°) or semirecumbent
(45° HOB elevation) position
Samples of gastric, pharyngeal, and bronchial secretions
obtained at baseline and hourly for 5 hours after
nasogastric tube instillation of technetium Tc 99m
Specimens were examined for radioactivity and
microbiological cultures were obtained
Radioactivity of pharyngeal secretions higher
with patients supine from hours 1-4, P <.05;
however, no difference noted at 5 hours
Radioactivity in bronchial secretions higher
at 5 hours in supine patients compared
with baseline (P < .05) and semirecumbency
(P < .01)
Results of microbiological cultures showed
a sequence of colonization from the stomach to the pharynx in 6 patients (4 of them
supine), and from the pharynx to the
bronchi in 2 others (one supine and one
semirecumbent)
GER is a frequent feature in patients with
nasogastric tubes
GER occurs irrespective of body position
in patients undergoing mechanical ventilation
A semirecumbent position lessens aspiration, but does not completely prevent it
Patients assigned to supine (0° HOB elevation) or
semirecumbent group (45° HOB elevation)
GER assessed by scintigraphy after gastric contents
labeled with technetium Tc 99m via the nasogastric
tube
In the 50 patients with nasogastric tubes,
incidence of GER higher in supine patients
(81%, 21/26) than in semirecumbent
patients (67%, 16/24), P = .26
In the 20 patients without nasogastric tubes,
GER was also more frequent in supine
position (50%, 6/12) than in the semirecumbent position (12%, 1/8), P = .16
Overall, GER more frequent in patients with
nasogastric tubes than in those without
(74% vs 35%, P < .001)
Incidence of GER is high in patients with
orotracheal intubation and nasogastric
tubes
Semirecumbency does not prevent GER,
although GER tends to occur less often
in semirecumbent patients
Random assignment to supine (0°) or semirecumbent
(45° HOB elevation) position
Correctness of assigned body position checked daily
Surveillance for clinical detection of pneumonia done
daily; samples for microbiological diagnostic tests
taken if infection clinically suspected
Standard pressure area care protocol applied in all
patients (water-filled cushion placed under sacral
region); method of monitoring for pressure ulcers
not described
Microbiologically confirmed pneumonia
occurred less often in the semirecumbent
group than in the supine group (2/39 [5%]
vs 11/47 [23%], respectively, P = .02)
Highest risk for nosocomial pneumonia
occurred in patients receiving tube feedings
in the supine position
No adverse effects of the semirecumbent
position were found; investigators emphasized use of protective measures to prevent
pressure ulcers
45° HOB elevation reduces frequency of
pneumonia, especially in tube-fed
patients
Observed 16 hours per day for 3 days; HOB elevation
recorded hourly; other risk factors for aspiration also
recorded
Tracheal secretions assayed for pepsin (proxy for aspiration of gastric contents)
Pneumonia assessed by Simplified Clinical Pulmonary
Infection Score on day 4
Mean HOB angle compared with percentage of aspiration and incidence of pneumonia
At least 1 aspiration event identified in 89%
of participants
Patients with mean HOB elevation <30°
(n = 226) had higher percentage of aspiration than did the 134 patients with mean
HOB ≥30° (35% vs 25%, P < .001)
Mean HOB elevation <30° found significantly
more often in patients with pneumonia
than in those without (P = .02)
Higher percentage of pepsin-positive secretions found in patients with pneumonia than
in those without (42% vs 21%, P < .001)
Other significant risk factors were decreased
level of consciousness, vomiting, and GER
Microaspiration common in critically ill,
tube-fed patients receiving mechanical
ventilation
Frequent aspiration significantly increases
risk for pneumonia
HOB elevation <30° is a significant risk
factor for aspiration and pneumonia
Continued
Table 2
Source
Continued
Sample
Design
Outcome
Metheny et al,35 Nursing
Research, 2010
474 critically ill, tube-fed patients receiving
mechanical ventilation
Intervention group, 145; usual care
group, 329
Mean age, 49-53 y
Two-group quasi-experimental
study
Aspiration of gastric contents
Pneumonia
van Nieuwenhoven et al,36
Critical Care Medicine, 2006
221 critically ill patients receiving mechanical ventilation
Standard care group, 109; semirecumbent group, 112
(Mean ages 63-65 y)
Prospective multicenter
randomized 2-group trial
Ventilator-associated pneumonia
(VAP)
Pressure ulcers
Keeley,37 Nursing in Critical
Care, 2007
30 critically ill patients receiving mechanical
ventilation completed the study
Treatment group, 17; control group, 13
Mean ages, 64-68 y
Randomized controlled trial
VAP
Nonetheless, results from these studies are helpful in current practice because they clearly show that a 45º HOB elevation is superior to a “flat in bed” position in preventing
aspiration. Recommendations in guidelines to prevent
aspiration are largely based on these trials.
No randomized controlled trials were identified that
compare aspiration while patients are at a 30º HOB elevation versus a 0º elevation, or a 30º elevation versus a 45º
elevation. Thus, although a 30º HOB elevation is commonly recommended in practice settings, there is no direct
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evidence that it is as effective as a 45º elevation in reducing
aspiration. However, as indicated in Table 2, several
descriptive studies34,35 suggest that an HOB elevation of 30º
or greater is associated with fewer adverse outcomes (aspiration and pneumonia) than is a lower HOB elevation. It
must be noted that evidence garnered from descriptive
studies is not as strong as evidence obtained from a controlled trial where patients are randomly assigned to differing HOB elevations. Further, the descriptive studies34-37
described in Table 2 have typically included HOB elevation
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Method
Results
Conclusions
Intervention group compared with usual-care group
for 3 days for percentage of aspiration and incidence
of pneumonia (assessed by the Simplified Clinical
Pulmonary Infection Score)
Intervention consisted of encouraging HOB elevation
to 30° or greater and insertion of feeding tubes into
small bowel
Mean HOB elevation ≥30° found in 90% of
intervention group, as compared with 38%
of the usual-care group, P < .001
Small-bowel tube placements more frequent
in intervention group than in the usual care
group (75% vs 50%, respectively, P < .001)
Aspiration (defined as at least 1 pepsinpositive tracheal secretion) lower in the
intervention group than in the usual-care
group (39% vs 88%, P < .001)
Pneumonia lower in the intervention group
than in the usual care group (19% vs 48%,
respectively, P < .001)
Combination of HOB position elevated to
≥30° and use of small-bowel feeding
site can significantly reduce the incidence
of aspiration and aspiration-related
pneumonia in critically ill, tube-fed
patients receiving mechanical ventilation
109 patients randomly assigned to standard-care group
(10° HOB elevation) and 112 randomly assigned to
semirecumbent group (45° HOB elevation)
HOB angle measured continuously in 174 patients by
a monitor-linked device during the first week of
mechanical ventilation
VAP diagnosed by quantitative cultures of samples
obtained by bronchoscopic techniques
Pressure ulcer development staged daily by research
nurses
HOB elevation to 45° achieved only 15% of
study time in the semirecumbent group
Average HOB elevations were 9.8° and 16.1°
at day 1 and day 7 for supine group and
28.1° and 22.6° at day 1 and day 7 for the
semirecumbent group (P < .001)
Microbiologically confirmed VAP was diagnosed in 8/109 patients (7.3%) in the supine
group and in 13/112 patients (11.6%) in
the semirecumbent group (difference not
significant)
Pressure ulcers developed in 30% of the
patients assigned to the supine group and
in 28% of the patients assigned to the
semirecumbent group
Investigators concluded that a 45° HOB
elevation is not feasible in critically ill
patients receiving mechanical ventilation
Mean HOB <30° in all patients
Could not compare VAP at the assigned
HOB elevations (10° vs 45°) because
only a small number of patients were
positioned at 45°
Also could not compare pressure ulcer
development at the assigned positions
Patients randomized to treatment (45° HOB elevation)
or standard-care group (25° HOB elevation)
Study continued until 1 of the following conditions
occurred: extubation, death, successful weaning,
withdrawal at request of patient or next of kin, change
in patient’s position that lasted more than 6 of 24
hours, transfer to another department, or need for
prone positioning
In surviving patients, follow-up continued for 72 hours
after a study end point had been reached
Pneumonia diagnosed as either clinically suspected or
microbiologically confirmed.
HOB angle measured on a random selection of patients,
by using a protractor and plumb line
Patients repositioned every 2-4 hours, either side lying
or supine while the required HOB angle was maintained
5 of 17 patients (29%) in treatment group
contracted VAP, compared with 7 of 13
(56%) in the control group, P = .18
9 patients who expressed discomfort or who
wished to be cared for in positions other
than those to which they had been randomized were withdrawn
Incidence of pressure ulcers not described
Trend toward a reduction in VAP found in
patients nursed at 45°; however,
statistical significance was not achieved
Elevation of HOB to 45° may be poorly
accepted by patients who are not heavily
sedated
in context with multiple other variables, thus making it
difficult to determine the singular effect of HOB elevation on outcomes.
Following a systematic review of 3 of the trials33,36,37
described in Table 2, a European panel concluded that it
is uncertain whether a 45º HOB elevation is effective or
harmful in regard to pneumonia and pressure ulcers.45
One aspect considered in the panel’s deliberations was the
paucity of data to support the use of a 45º HOB elevation
for a sustained period.45 The authors questioned whether
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a 45º HOB elevation for 24 hours a day might increase
the risk for thromboembolism, hemodynamic instability,
and pressure ulcers. Although these are reasonable concerns, the 3 studies reviewed by the panel did not assess
for thromboembolism and hemodynamic instability and
only 1 referred to pressure ulcers as an outcome (noting
no difference at the end of 1 week between groups with
mean HOB elevations of 16º and 23º). Based on their
deliberations, the panel recommended an HOB elevation
of 20º to 45º for patients receiving mechanical ventilation
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Table 3
Source
Studies related to head-of-bed (HOB) elevation and pressure ulcers
Sample
Design
Outcome
Peterson et al, Critical Care
Medicine, 2008
15 healthy adults
Age range, 23-54 y
Descriptive observational study Peak sacral interface pressures
Harada et al,39 Journal of
Wound Ostomy Continence
Nursing, 2002
10 healthy Japanese women
Age range, 18-25 y
Comparative, quasiexperimental study with
repeated measures
Peterson et al,40 Journal of
Advanced Nursing, 2010
15 healthy adults
Age range, 23-54 y
Descriptive observational study Interface pressures in the sacral,
trochanteric, and buttock regions
Effectiveness of turning in unloading pressure on at-risk tissues
Gray-Siracusa and Schrier,41
Journal of Nursing Care
Quality, 2011
Total 1199 critically ill patients (554 in
“before” group and 645 in “after” group)
Two-group (before-after)
comparison study
Rate of hospital-acquired pressure
ulcers
Nanjo et al,42 Journal of
Wound Ostomy Continence
Nursing, 2011
30 adult critically ill patients
Mean age, 68 y
Qualitative exploratory study
Relationships among etiologic
factors, characteristics of pressure ulcers, and interventional
nursing care
38
Body displacement
Sacral interface pressure
Method
Results
Conclusions
Interface pressure profiles of the sacral area obtained
for the 0°, 10°, 20°, 30°, 45°, 60°, and 75° HOB
elevated positions
Measurements obtained using a thin pressure-sensing
pad placed under the sacral region
After repeated-measures analysis of variance, the HOB positions of 45°, 60°, and
75° all caused statistically significant
increases in affected areas compared with
the supine measurement (P < .001)
With the same statistical test, the areas with
>32 mm Hg interface pressure at the HOB
positions of 45°, 60°, and 75° were all
significantly different from all other HOB
positions
The 30° HOB elevation was different from
the 10° and the 20° HOB elevation positions (P < .02)
Raising the HOB to ≥30° significantly
increases the skin–support surface
interface pressure, and a ≥45° HOB
elevation significantly increases the
area of skin exposed to a pressure
>32 mm Hg
Subjects placed supine on standard hospital bed;
HOB then raised to 30° according to 2 protocols:
(1) supine for 10 minutes without leg elevation
alternating with 10 minutes of side-lying, or (2)
supine for 10 minutes with leg elevation at 10°
alternating with side-lying every 10 minutes
Difference over time between the top edge of the
mattress and subjects’ acromion measured every
10 minutes
Sacral interface pressure measured every 10 minutes
using a pneumatic pressure sensor
Body displacement and mean sacral interface pressures
in both protocols compared by using repeatedmeasures analysis of variance
Mean body displacement in 30° elevated
HOB position without leg elevation at the
end of 2 hours was 29 cm, whereas with
leg elevation it was 18 cm (P < .001)
No significant differences in sacral interface
pressures with or without leg elevation at
baseline (7.3 mm Hg and 11.9 mm Hg,
respectively)
Leg elevation at 10° in the 30° HOB elevated position is effective for reducing
body displacement; it is not effective
for reducing sacral interface pressures
Interface pressure profiles obtained from sacral,
trochanteric, and buttock regions while patients were
supine, followed by lateral turning with pillow or
wedge support and subsequent HOB elevation to 30°
Turning performed by an experienced intensive care
unit nurse
Peak perisacral area interface pressures not
significantly affected by lateral turning, but
demonstrated a significant increase upon
elevating the HOB to 30° (P < .05)
93% of participants had skin areas with
interface pressures ≥32 mm Hg throughout all positions (mean [SD], 60 [54] cm2),
termed “triple jeopardy area”
The triple jeopardy area increased significantly with wedges as compared with
pillows (mean [SD], 153 [99] cm2 vs 48
[47] cm2, P < .05)
Standard turning by experienced intensive care unit nurses does not reliably
unload all areas of high skin-bed interface pressures
Support materials for maintaining lateral
turned positions can influence tissue
unloading and triple jeopardy areas,
and need to be further evaluated to
improve care
Further study is needed to establish how
to achieve optimal positioning to eliminate areas that remain at risk
Determined rate of hospital-acquired pressure ulcers during year before implementation of bundle intervention
Implemented 7-item pressure ulcer bundle; portions
pertaining to HOB elevation included (1) elevating
HOB to 45º for all patients receiving mechanical ventilation, and (2) maintaining HOB at 30° or less for
patients who are not receiving mechanical ventilation, who are at lower risk
Determined rate of hospital-acquired pressure ulcers
during year following implementation of pressure
ulcer bundle
Analysis of quarterly hospital-acquired pressure ulcers rates before and after shows
no significant difference (P = .11)
Before pressure ulcer bundle, quarterly
survey results for hospital-acquired pressure ulcer rates were as follows: quarter
1 = 5.7%; quarter 2 = 0%; quarter 3 = 5.2%,
and quarter 4 = 0%
After implementation of pressure ulcer bundle,
quarterly hospital-acquired pressure ulcer
rates remained <1% through the year
Pressure ulcer bundle reduced the incidence of pressure ulcers but difference
was not statistically significant
Details of 30 individual pressure ulcers described by
sketching pressure ulcer photographs
Characteristics of pressure ulcers divided into 4
categories: (1) location, (2) shape, (3) type of skin
lesion, and (4) periwound skin
After identification of pressure ulcer characteristics,
in-depth review of medical records to evaluate the
pressure ulcers’ development process
Semistructured interviews with 5 nurses who cared
for patients in study; topics included position and
positioning methods, criteria for deciding how to
position a particular patient, and typical interventions
to prevent pressure ulcers
Pressure ulcer sites:
Upper sacrum (n = 5)
Lower sacrum (n = 14)
Coccyx (n = 8)
Ischium (n = 1)
Heel/ankle (n = 2)
Possible etiological factors for specific
pressure ulcer divided into 4 categories:
(1) occurrence of pressure ulcer risk
episodes, (2) failure of peripheral circulation, (3) periods of critical immobility, and
(4) position change techniques inducing
skin deformation
Frequently repeated position changes,
such as lateral tilt and repeated HOB
elevation, may cause deformation of
the sacral skin and possibly play a role
in development of pressure ulcers
Continued
Table 3
Source
Continued
Sample
Design
Outcome
Sideranko et al,43 Research in
Nursing and Health, 1992
57 patients in a surgical intensive care unit
Repeated measures study
Sacral and heel pressures
Development of pressure ulcers
Sanada et al,44 Journal of Tissue Viability, 2003
82 patients from general care area in hospital
Mean age range, 69.5-73.9 y
Randomized controlled trial
Development of pressure ulcers
(preferably ≥ 30º) as long as it does not conflict with
medical interventions, patients’ wishes, or nursing tasks.
benefit of pressure-relieving surfaces in preventing pressure ulcers.43,44
Evidence to Support a Low HOB
Elevation to Prevent Pressure Ulcers
Compliance With Guidelines
in Critical Care Settings
Overall, less research is available about the effect of
HOB elevation on pressure ulcer development than on
aspiration; further, relatively few studies have been conducted in a critical care setting. Three of the studies38-40
described in Table 3 were conducted with healthy persons
and show that interface pressure between the skin and
bed surface is increased as the HOB angle is increased.
One of the
Using a lift sheet to reposition patients
studies39 also
reduces shear pressure and lowers risk for
suggests that
pressure ulcers.
sliding down
in bed is more likely at a 30º HOB angle than when the
bed is flat. No randomized controlled trials were identified that compared the effect of various HOB elevations
on development of pressure ulcers. However, 1 group of
investigators41 compared pressure ulcer outcomes before
and after the implementation of a pressure ulcer bundle
(1 component of which was manipulation of the HOB
angle) in a critical care setting. A trend toward reduction
in pressure ulcer rates was noted, although statistical
significance was not achieved. Two other studies described
in Table 3 are examples of projects that demonstrate the
62
CriticalCareNurse
Vol 33, No. 3, JUNE 2013
Aspiration Guidelines
Among contraindications to an elevated HOB position are recent lumbar spine injury, hemodynamic instability, trauma of the pelvic region, and severe sacral
pressure ulcers. Even when there are no contraindications to an elevated HOB position, it is not consistently
applied. (See the study by van Nieuwenhoven et al36 in
Table 2.) A variety of strategies have been studied in
regard to increasing use of an elevated HOB position.
For example, Helman et al46 implemented a standardized
order for placing patients in a 45º HOB elevated position, along with an educational program for nurses and
physicians; however, compliance with the order was
achieved in less than one-third of the observations.
Nurses who participated in that study reported the following concerns:
• Increased probability of patient sliding down in bed
• More difficulty in turning patient from side to side
• Greater pressure exerted on patient’s sacral area
• Greater discomfort and interference with sleep
Even a 30º HOB-elevated position is not consistently
used in some critical care settings.15,47,48 In 2003, Grap et al47
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Method
Results
Conclusions
Subjects divided into 3 groups according to type of
pressure-relieving surface: (1) alternating air (n = 20);
(2) static air (n = 20); and (3) water mattress (n = 17)
Pressures recorded from sacrum and heel in the dorsal recumbent position; same measurements made
while patient positioned at a 45° HOB elevation
Sacral and heel pressures tested for each surface, at
each HOB position, using a repeated-measures design
Mean pressure with alternating air mattress
was 30 mm Hg; it was 23.3 mm Hg with
the water mattress and 25 mm Hg with
the static air mattress (P < .01)
The 45° HOB elevated position (regardless
of pressure-relieving surface) produced
significantly more sacral pressure at an
average of 32.9 mm Hg, as compared with
recumbent position average (25.1 mm Hg;
P < .01)
Heel pressures showed no differences
across mattress type and position
Pressure ulcers developed in 8 patients (5 on
alternating air, 2 on water, and 1 on static
air surface); χ2 analysis not significant
Findings suggest that alternating air
overlays should be avoided
Investigators emphasized importance of
periodically repositioning patients who
require a prolonged HOB elevation to
reduce the incidence of sacral pressure
ulcers
Participants were patients who had Braden scale
scores ≤16 and required a HOB elevation ≥45°
Assigned to 1 of 3 support surfaces: (1) double-layer
air-cell overlay, (2) single-layer air-cell overlay, or
(3) standard hospital mattress
Incidence of pressure ulcers according to
support surface were as follows:
Double-layer air-cell overlay, 3.4%
Single-layer air-cell overall, 19.2%
Standard mattress, 37%
Standard mattress associated with a
much higher incidence of pressure
ulcers than pressure-relieving surfaces
in a population of patients who
required a 45° HOB elevated position
reported that the mean backrest elevation in a population
of 170 critically patients was 19.2º. Although an elevated
HOB position is especially warranted in tube-fed patients,
there was no difference in backrest elevation between
patients being fed and not being fed. In a 2005 study15 of
66 critically ill patients monitored during 275 patient
days, investigators found that backrest elevations were
less than 30º 72% of the time. More encouraging findings
were reported in a later study49 conducted in a thoracic
ICU; mean compliance with an HOB elevated position
greater than 30º changed from 65% in 2007 to 99% in
2009; associated with this increased compliance was a
significant decrease in the incidence of VAP.
HOB elevation is related to acuity level. For example,
Evans48 found a significant negative correlation (r2 =-0.17)
between scores on the Acute Physiology and Chronic
Health Evaluation II and HOB elevation in 113 critically ill
patients. Evans48 also reported that patients receiving
mechanical ventilation had a lower mean HOB elevation
than did self-ventilating patients (19º vs 32º). In a study50 of
100 patients in a thoracic cardiovascular ICU, investigators
found that patients with a mean arterial blood pressure
of 64 mm Hg or less had a lower mean backrest elevation
(17º) than did patients with a higher arterial pressure
(24º). In a study of 438 patients, investigators51 reported
that mean HOB elevations were lower in intubated
patients (23º) than in nonintubated patients (33º, P<.001).
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Delivery of standard nursing care often calls for temporary lowering of the HOB elevation. For example,
because it is difficult to turn patients when the bed’s
backrest is elevated, nurses usually lower the bed to 0º
(in some instances,
Elevating the HOB decreases risk
they may even put
for aspiration but increases risk for
the bed in reverse
pressure ulcers.
Trendelenberg position while turning patients and pulling them up in bed).
There are reports of nurses forgetting to elevate the backrest after completing the turning procedure (sometimes
for a period up to 1 hour).52,53 Medical procedures (such
as insertions of central catheters) can cause temporary
interruptions in the desired HOB elevation. Transitory
physiological conditions such as hemodynamic instability or low cerebral perfusion pressure also may mandate
lowering of the HOB elevation.
Another possible reason for noncompliance with an
elevated HOB position is difficulty in making accurate
visual estimates of an HOB angle. For example, Hiner et
al54 asked 175 clinicians to estimate a simulated HOB
angle of 30º; the angle was perceived accurately by 50%
of 89 nurses and 53% of 39 physicians; a higher percentage (86%) of 21 respiratory therapists identified the
angle accurately. These findings are significant because
some hospital beds do not have built-in electronic
devices to determine the bed’s angle.
CriticalCareNurse
Vol 33, No. 3, JUNE 2013
63
Pressure Ulcer Guidelines
No studies were located that measured adherence to
a low (≤30º) HOB elevation to prevent pressure ulcers in
critically ill patients. However, in a study55 involving 362
long-term care facilities in Missouri, researchers found
that minimizing the HOB elevation to less than 30º was
done by fewer than 20% of the facilities.
Conclusions
The optimal HOB elevation to balance the risks for
aspiration and pressure ulcers is unknown.15,39,56-58 Thus, a
need exists for randomized controlled trials where both
outcomes (aspiration and pressure ulcers) are evaluated
simultaneously at various HOB elevated positions, especially in a population of critically ill, tube-fed patients
receiving mechanical ventilation. Some authors suggest
that studies be conducted to compare the commonly
recommended 30º to 45º HOB elevations to lower and
more achievable levels (such as 10º to 30º).59
Until more research-based evidence is available,
caregivers should consider guidelines from expert panels
and ultimately make decisions about HOB elevation in
the context of the patient’s overall condition. Given current information, the following recommendations may
be helpful to critical care clinicians:
• Unless medically contraindicated, maintain an
HOB elevation of 45º in patients who are receiving mechanical ventilation and tube feedings. If
necessary for comfort, lower the HOB elevation
to 30º periodically.
• For critically ill patients at less risk for aspiration
(eg, patients who are not receiving mechanical
ventilation), maintain an HOB elevation of at
least 30º unless medically contraindicated.
• Use a pressure-relieving surface for all critically
ill patients to reduce the skin-bed interface pressure associated with an elevated HOB position.
Routinely assess the patient’s skin for signs of a
developing pressure ulcer.
• To minimize shear pressure, use a lift sheet to
reposition patients (instead of sliding the patient
up in bed). CCN
Financial Disclosures
None reported.
64
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Vol 33, No. 3, JUNE 2013
Now that you’ve read the article, create or contribute to an online discussion
about this topic using eLetters. Just visit www.ccnonline.org and click “Submit a
response” in either the full-text or PDF view of the article.
To learn more about head-of-bed elevation in the critical care
setting, read “Clinicians’ Perception of Head-of-Bed Elevation”
by Hiner et al in the American Journal of Critical Care, March
2010;19:164-167. Available at www.ajcconline.org.
References
1. Heyland DK, Dhaliwal R, Drover JW, et al. Canadian clinical practice
guidelines for nutrition support in mechanically ventilated, critically ill
adult patients [see comment]. JPEN J Parenter Enteral Nutr. 2003;27(5):
355-373.
2. Collard HR, Saint S, Matthay MA. Prevention of ventilator-associated
pneumonia: an evidence-based systematic review [see comment]. Ann
Intern Med. 2003;138(6):494-501.
3. Muscedere J, Dodek P, Keenan S, et al. Comprehensive evidence-based
clinical practice guidelines for ventilator-associated pneumonia: diagnosis and treatment. J Crit Care. 2008;23(1):138-147.
4. McClave SA, Martindale RG, Vanek VW, et al. Guidelines for the provision and assessment of nutrition support therapy in the adult critically
ill patient: Society of Critical Care Medicine (SCCM) and American
Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). JPEN J Parenter
Enteral Nutr. 2009;33(3):277-316.
5. Bankhead R, Boullata J, Brantley S, et al. Enteral nutrition practice recommendations. JPEN J Parenter Enteral Nutr. 2009;33(2):122-167.
6. McClave SA, DeMeo MT, DeLegge MH, et al. North American Summit
on Aspiration in the Critically Ill Patient: consensus statement. JPEN J
Parenter Enteral Nutr. 2002;26(6 Suppl):S80-S85.
7. Kirby DF, Delegge MH, Fleming CR. American Gastroenterological
Association technical review on tube feeding for enteral nutrition. Gastroenterology. 1995;108(4):1282-1301.
8. Tablan OC, Anderson LJ, Besser R, et al. Guidelines for preventing
health-care–associated pneumonia, 2003: recommendations of CDC
and the Healthcare Infection Control Practices Advisory Committee.
Morbid Mortal Wkly Rep. 2004;53(RR-3):1-36.
9. American Association of Critical-Care Nurses. Practice Alert: VentilatorAssociated Pneumonia. Aliso Viejo, CA: American Association of CriticalCare Nurses; 2008.
10. American Association of Critical-Care Nurses. Practice Alert: Prevention
of Aspiration. Aliso Viejo, CA: American Association of Critical-Care
Nurses; 2011.
11. National Pressure Ulcer Advisory Panel. Prevention and Treatment of
Pressure Ulcers: Clinical Practice Guideline. Washington, DC: National
Pressure Ulcer Advisory Panel; 2009.
12. Wound Ostomy and Continence Nurses Association. Guideline for Prevention and Management of Pressure Ulcers. Mount Laurel, NJ: Wound
Ostomy and Continence Nurses Association; 2010:96.
13. Stechmiller JK, Cowan L, Whitney JD, et al. Guidelines for the prevention of pressure ulcers. Wound Repair Regen. 2008;16(2):151-168.
14. Cahill NE, Narasimhan S, Dhaliwal R, Heyland DK. Attitudes and
beliefs related to the Canadian critical care nutrition practice guidelines:
an international survey of critical care physicians and dietitians. JPEN J
Parenter Enteral Nutr. 2010;34(6):685-696.
15. Grap MJ, Munro CL, Hummel RS III, Elswick RK Jr, McKinney JL,
Sessler CN. Effect of backrest elevation on the development of ventilator-associated pneumonia. Am J Crit Care. 2005;14(4):325-332.
16. Estilo MEL, Angeles A, Perez T, Hernandez M, Valdez M. Pressure
ulcers in the intensive care unit: new perspectives on an old problem.
Crit Care Nurse. 2012;32(3):65-70.
17. O’Keefe GE, Caldwell E, Cuschieri J, Wurfel MM, Evans HL. Ventilatorassociated pneumonia: bacteremia and death after traumatic injury. J
Trauma Acute Care Surg. 2012;72(3):713-719.
18. Safdar N, Dezfulian C, Collard HR, Saint S. Clinical and economic consequences of ventilator-associated pneumonia: a systematic review. Crit
Care Med. 2005;33(10):2184-2193.
www.ccnonline.org
19. Centers for Medicare and Medicaid Services. Proposed Changes to the
Hospital Inpatient Prospective Payment Systems and Fiscal Year 2009 Rates.
Baltimore, MD: Centers for Medicare and Medicaid Services; 2009.
20. Redelings MD, Lee NE, Sorvillo F. Pressure ulcers: more lethal than we
thought? Adv Skin Wound Care. 2005;18(7):367-372.
21. Weststrate J, Tweed C, Naylor W. Death highlights poor ulcer care.
Nurs N Z. 2009;15(4):16-18.
22. Santangelo A, Testai M, Ossino MC, et al. Management and treatment
of decubital ulcers of an elderly population in the assisted sanitary residence of Futura-Viagrande (Catania, Sicily, Italy). Arch Gerontol Geriatr.
2009;48(3):332-334.
23. VanGilder C, Amlung S, Harrison P, Meyer S. Results of the 2008-2009
International Pressure Ulcer Prevalence Survey and a 3-year, acute care,
unit-specific analysis. Ostomy Wound Manage. 2009;55(11):39-45.
24. Schessel ES, Ger R, Oddsen R. The costs and outcomes of treating a deep
pressure ulcer in a patient with quadriplegia [erratum appears in Ostomy
Wound Manage. 2012;58(3):8]. Ostomy Wound Manage. 2012;58(2):41-46.
25. Jackson M, McKenney T, Drumm J, Merrick B, LeMaster T, VanGilder
C. Pressure ulcer prevention in high-risk postoperative cardiovascular
patients. Crit Care Nurse. 2011;31(4):44-53.
26. Cox J. Predictors of pressure ulcers in adult critical care patients. Am J
Crit Care. 2011;20(5):364-375.
27. Miller CD, Rebuck JA, Ahern JW, Rogers FB. Daily evaluation of macroaspiration in the critically ill post-trauma patient. Curr Surg. 2005;62(5):
504-508.
28. McClave SA, Lukan JK, Stefater JA, et al. Poor validity of residual volumes
as a marker for risk of aspiration in critically ill patients [comment].
Crit Care Med. 2005;33(2):324-330.
29. Barczak CA, Barnett RI, Childs EJ, Bosley LM. Fourth national pressure
ulcer prevalence survey. Adv Wound Care. 1997;10(4):18-26.
30. Torres A, Serra-Batlles J, Ros E, et al. Pulmonary aspiration of gastric
contents in patients receiving mechanical ventilation: the effect of body
position. Ann Intern Med. 1992;116(7):540-543.
31. Orozco-Levi M, Torres A, Ferrer M, et al. Semirecumbent position protects from pulmonary aspiration but not completely from gastroesophageal reflux in mechanically ventilated patients. Am J Respir Crit
Care Med. 1995;152(4 pt 1):1387-1390.
32. Ibanez J, Penafiel A, Raurich JM, Marse P, Jorda R, Mata F. Gastroesophageal reflux in intubated patients receiving enteral nutrition: effect
of supine and semirecumbent positions. JPEN J Parenter Enteral Nutr.
1992;16(5):419-422.
33. Drakulovic MB, Torres A, Bauer TT, Nicolas JM, Nogue S, Ferrer M.
Supine body position as a risk factor for nosocomial pneumonia in
mechanically ventilated patients: a randomised trial. Lancet. 1999;
354(9193):1851-1858.
34. Metheny NA, Clouse RE, Chang YH, Stewart BJ, Oliver DA, Kollef MH.
Tracheobronchial aspiration of gastric contents in critically ill tube-fed
patients: frequency, outcomes, and risk factors. Crit Care Med. 2006;
34(4):1-9.
35. Metheny NA, Davis-Jackson J, Stewart BJ. Effectiveness of an aspiration
risk-reduction protocol. Nurs Res. 2010;59(1):18-25.
36. van Nieuwenhoven CA, Vandenbroucke-Grauls C, van Tiel FH, et al.
Feasibility and effects of the semirecumbent position to prevent ventilatorassociated pneumonia: a randomized study [see comment]. Crit Care
Med. 2006;34(2):396-402.
37. Keeley L. Reducing the risk of ventilator-acquired pneumonia through
head of bed elevation. Nurs Crit Care. 2007;12(6):287-294.
38. Peterson M, Schwab W, McCutcheon K, van Oostrom JH, Gravenstein N,
Caruso L. Effects of elevating the head of bed on interface pressure in
volunteers. Crit Care Med. 2008;36(11):3038-3042.
39. Harada C, Shigematsu T, Hagisawa S. The effect of 10-degree leg elevation
and 30-degree head elevation on body displacement and sacral interface
pressures over a 2-hour period. J Wound Ostomy Continence Nurs. 2002;
29(3):143-148.
40. Peterson MJ, Schwab W, van Oostrom JH, Gravenstein N, Caruso LJ.
Effects of turning on skin-bed interface pressures in healthy adults. J Adv
Nurs. 2010;66(7):1556-1564.
41. Gray-Siracusa K, Schrier L. Use of an intervention bundle to eliminate
pressure ulcers in critical care. J Nurs Care Qual. 2011;26(3):216-225.
42. Nanjo Y, Nakagami G, Kaitani T, et al. Relationship between morphological characteristics and etiology of pressure ulcers in intensive care
unit patients. J Wound Ostomy Continence Nurs. 2011;38(4):404-412.
43. Sideranko S, Quinn A, Burns K, Froman RD. Effects of position and
mattress overlay on sacral and heel pressures in a clinical population.
Res Nurs Health. 1992;15(4):245-251.
www.ccnonline.org
44. Sanada H, Sugama J, Matsui Y, et al. Randomised controlled trial to evaluate a new double-layer air-cell overlay for elderly patients requiring
head elevation. J Tissue Viability. 2003;13(3):112-114, 116, 118 passim.
45. Niel-Weise BS, Gastmeier P, Kola A, et al. An evidence-based recommendation on bed head elevation for mechanically ventilated patients. Crit
Care (London, England). 2011;15(2):R111.
46. Helman DL Jr, Sherner JH III, Fitzpatrick TM, Callender ME, Shorr AF.
Effect of standardized orders and provider education on head-of-bed
positioning in mechanically ventilated patients. Crit Care Med. 2003;
31(9):2285-2290.
47. Grap MJ, Munro CL, Bryant S, Ashtiani B. Predictors of backrest elevation
in critical care. Intensive Crit Care Nurs. 2003;19(2):68-74.
48. Evans D. The use of position during critical illness: current practice and
review of the literature. Australian Crit Care. 1994;7(3):16-21.
49. Bird D, Zambuto A, O’Donnell C, et al. Adherence to ventilator-associated
pneumonia bundle and incidence of ventilator-associated pneumonia in
the surgical intensive care unit. Arch Surg. 2010;145(5):465-470.
50. Ballew C, Buffmire MV, Fisher C, et al. Factors associated with the level
of backrest elevation in a thoracic cardiovascular intensive care unit. Am
J Crit Care. 2011;20(5):395-399.
51. Hanneman SK, Gusick GM. Frequency of oral care and positioning of
patients in critical care: a replication study. Am J Crit Care. 2005;14(5):
378-386.
52. De Jonghe B, Appere-De-Vechi C, Fournier M, et al. A prospective survey
of nutritional support practices in intensive care unit patients: what is
prescribed? What is delivered? Crit Care Med. 2001;29(1):8-12.
53. McClave SA, Sexton LK, Spain DA, et al. Enteral tube feeding in the
intensive care unit: Factors impeding adequate delivery. Crit Care Med.
1999;27(7):1252-1256.
54. Hiner C, Kasuya T, Cottingham C, Whitney J. Clinicians’ perception of
head-of-bed elevation. Am J Crit Care. 2010;19(2):164-167.
55. Wipke-Tevis DD, Williams DA, Rantz MJ, et al. Nursing home quality
and pressure ulcer prevention and management practices. J Am Geriatr
Soc. 2004;52(4):583-588.
56. Johnson KL, Meyenburg T. Physiological rationale and current evidence
for therapeutic positioning of critically ill patients. AACN Adv Crit Care.
2009;20(3):228-240; quiz 241-222.
57. Li Bassi G, Torres A. Ventilator-associated pneumonia: role of positioning.
Curr Opin Crit Care. 2011;17(1):57-63.
58. Naccarato MK, Kelechi T. Pressure ulcer prevention in the emergency
department. Adv Emerg Nurs J. 2011;33(2):155-162.
59. Wip C, Napolitano L. Bundles to prevent ventilator-associated pneumonia: how valuable are they? Curr Opin Infect Dis. 2009;22(2):159-166.
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CCN Fast Facts
CriticalCareNurse
The journal for high acuity, progressive, and critical care nursing
Head-of-Bed Elevation in Critically Ill Patients: A Review
Facts
There are conflicting guidelines about the use of
head-of-bed (HOB) elevation to prevent aspiration and
pressure ulcers in critically ill patients.
• Although the recommendations overlap, a 45º
HOB elevation is generally favored to prevent
aspiration in critically ill patients who are receiving mechanical ventilation and tube feedings.
Because aspiration is a threat to oxygenation, it
may be a more immediate concern than are pressure ulcers in critically ill patients.
• Aspiration of gastric contents is a primary route of
bacterial entry into the lungs and is an important
factor in the development of ventilator-associated
pneumonia.
• Pressure ulcers are also associated with adverse
outcomes and increased hospital costs. A pressure
ulcer is often a marker for coexisting illness and
other risk factors for mortality.
• Results from early studies are helpful in current
practice because they clearly show that a 45º HOB
elevation is superior to a “flat in bed” position in
preventing aspiration.
• No randomized controlled trials were identified
that compare aspiration while patients are at a 30º
HOB elevation versus a 0º elevation, or a 30º elevation versus a 45º elevation. Thus, although a 30º
HOB elevation is commonly recommended in practice settings, there is no direct evidence that it is as
effective as a 45º elevation in reducing aspiration.
• Contraindications to an elevated HOB position are
recent lumbar spine injury, hemodynamic instability, trauma of the pelvic region, and severe sacral
pressure ulcers. Even when there are no contraindications to an elevated HOB position, it is not consistently applied.
• Standard nursing care often calls for temporary
lowering of the HOB elevation. For example,
because it is difficult to turn patients when the
bed’s backrest is elevated, nurses usually lower
the bed to 0º. There are reports of nurses forgetting to elevate the backrest after completing the
turning procedure. Medical procedures also can
cause temporary interruptions in the desired
HOB elevation. Transitory physiological conditions such as hemodynamic instability or low
cerebral perfusion pressure also may mandate
lowering of the HOB elevation.
Conclusions
Until more research-based evidence is available, caregivers should consider guidelines from expert panels and
ultimately make decisions about HOB elevation in the
context of the patient’s overall condition. Given current
information, the following recommendations may be
helpful to critical care clinicians:
• Unless medically contraindicated, maintain an HOB
elevation of 45º in patients who are receiving mechanical ventilation and tube feedings. If necessary for
comfort, lower the HOB elevation to 30º periodically.
• For critically ill patients at less risk for aspiration
(eg, patients who are not receiving mechanical ventilation), maintain an HOB elevation of at least 30º
unless medically contraindicated.
• Use a pressure-relieving surface for all critically ill
patients to reduce the skin-bed interface pressure
associated with an elevated HOB position. Routinely assess the patient’s skin for signs of a developing pressure ulcer.
• To minimize shear pressure, use a lift sheet to reposition patients (instead of sliding the patient up in
bed). CCN
Metheny NA, Frantz RA. Head-of-Bed Elevation in Critically Ill Patients: A Review. Critical Care Nurse. 2013;33(3):53-67.
66
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