CE ONLINE
The Role of Irrigation Fluid
Warming in Hypothermia
Prevention
A Continuing Education Activity
Sponsored By
Grant Funds Provided By
Welcome to
The Role of Irrigation Fluid
Warming in Hypothermia
Prevention
(An Online Continuing Education Activity)
CONTINUING EDUCATION INSTRUCTIONS
This educational activity is being offered online and may be completed at any time.
Steps for Successful Course Completion
To earn continuing education credit, the participant must complete the following steps:
1. Read the overview and objectives to ensure consistency with your own learning
needs and objectives. At the end of the activity, you will be assessed on the
attainment of each objective.
2. Review the content of the activity, paying particular attention to those areas that
reflect the objectives.
3. Complete the Test Questions. Missed questions will offer the opportunity to reread the question and answer choices. You may also revisit relevant content.
4. For additional information on an issue or topic, consult the references.
5. To receive credit for this activity complete the evaluation and registration form.
6. A certificate of completion will be available for you to print at the conclusion.
Pfiedler Enterprises will maintain a record of your continuing education credits and
provide verification, if necessary, for 7 years. Requests for certificates must be
submitted in writing by the learner.
If you have any questions, please call: 720-748-6144.
CONTACT INFORMATION:
© 2013
All rights reserved
Pfiedler Enterprises, 2101 S. Blackhawk Street, Suite 220, Aurora, Colorado 80014
www.pfiedlerenterprises.com Phone: 720-748-6144 Fax: 720-748-6196
OVERVIEW
Preventing unplanned hypothermia for all surgical patients is an important component of
perioperative nursing care. However, the development of unintended hypothermia is a
common occurrence throughout all phases of a patient’s perioperative experience. The
complications associated with unintended perioperative hypothermia are significant and
well documented in the literature. Furthermore, treatment of these consequences incurs
unnecessary costs for health care facilities. Therefore, it is critical that perioperative
nurses understand the importance of maintaining normothermia in all surgical patients.
Today, there are several strategies available to maintain normothermia in surgical patients;
intraoperative irrigation fluid warming is one method that makes hypothermia prevention
an achievable goal. This continuing education activity will provide a review of the definition
and phases of unintended perioperative hypothermia. Patient complications due to
unplanned hypothermia and the clinical and cost benefits of maintaining normothermia, as
documented in the literature, will be discussed. Finally, the role of intraoperative irrigation
fluid warming as an effective method to prevent unintended hypothermia, including its
clinical benefits, warming methods, and best practices, will be outlined.
Objectives
Upon completion of this continuing nursing education activity, the participant should be
able to:
1. Define hypothermia.
2. Distinguish the phases of unplanned perioperative hypothermia.
3. Identify the common patient complications associated with unintended
perioperative hypothermia as documented in the literature.
4. Describe the clinical and economic benefits of maintaining normothermia
throughout a patient’s surgical experience.
5. Discuss the role of intraoperative irrigation fluid warming in hypothermia
prevention.
INTENDED AUDIENCE
This continuing education activity is intended for nurses and other health care personnel
who are interested in learning more about the role of intraoperative irrigation fluid warming
in preventing unplanned perioperative hypothermia.
CREDIT/CREDIT INFORMATION
AST Credit
This continuing education activity is approved for 3.0 CE credits by the Association of
Surgical Technologists, Inc. for continuing education for the Certified Surgical Technologist
and Certified Surgical First Assistant. This recognition does not imply that AST approves or
endorses and product or products that are discussed or mentioned in enduring material.
3
RELEASE AND EXPIRATION DATE
This continuing education activity was planned and provided in accordance with accreditation
criteria. This material was originally produced in April 2013 and can no longer be used after
April 2015 without being updated; therefore, this continuing education activity expires in April
2015.
DISCLAIMER
Accredited status as a provider refers only to continuing nursing education activities and does
not imply endorsement of any products.
SUPPORT
Grant funds for the development of this activity were provided by ECOLAB.
AUTHORS/PLANNING COMMITTEE/REVIEWERS
Julia A. Kneedler, RN, MS, EdD
Director of Education
Pfiedler Enterprises
Aurora, CO
Judith I. Pfister, RN, BSN, MBA
Program Manager
Pfiedler Enterprises
Aurora, CO
Kathryn Major, RN, BSN Program Manager
Pfiedler Enterprises
Aurora, CO
Rose Moss, RN, MN, CNOR
Nurse Consultant
Elizabeth, CO
4
DISCLOSURE OF RELATIONSHIPS WITH COMMERCIAL ENTITIES
FOR THOSE IN A POSITION TO CONTROL CONTENT FOR THIS
ACTIVITY
Pfiedler Enterprises has a policy in place for identifying and resolving conflicts of interest
for individuals who control content for an educational activity. Information listed below
is provided to the learner, so that a determination can be made if identified external
interests or influences pose a potential bias of content, recommendations or conclusions.
The intent is full disclosure of those in a position to control content, with a goal of
objectivity, balance and scientific rigor in the activity.
Disclosure includes relevant financial relationships with commercial interests related to
the subject matter that may be presented in this educational activity. “Relevant financial
relationships” are those in any amount, occurring within the past 12 months that
create a conflict of interest. A “commercial interest” is any entity producing, marketing,
reselling, or distributing health care goods or services consumed by, or used on, patients.
Activity Planning Committee/Authors/Reviewers:
Julia A. Kneedler, RN, MS, EdD
Co-owner of company that receives grant funds from commercial entities
Judith I. Pfister, RN, BSN, MBA
Co-owner of company that receives grant funds from commercial entities
Kathryn Major, RN, BSN
No conflicts of interest
Rose Moss, RN, MN, CNOR
No conflicts of interest
PRIVACY AND CONFIDENTIALITY POLICY
Pfiedler Enterprises is committed to protecting your privacy and following industry best
practices and regulations regarding continuing education. The information we collect
is never shared for commercial purposes with any other organization. Our privacy and
confidentiality policy is covered at our website, www.pfiedlerenterprises.com, and is
effective on March 27, 2008.
To directly access more information on our Privacy and Confidentiality Policy, type the
following URL address into your browser: http://www.pfiedlerenterprises.com/privacypolicy
In addition to this privacy statement, this Website is compliant with the guidelines for
internet-based continuing education programs.
The privacy policy of this website is strictly enforced.
5
CONTACT INFORMATION
If site users have any questions or suggestions regarding our privacy policy, please
contact us at:
Phone: 720-748-6144
Email:
[email protected]
Postal Address: 2101 S. Blackhawk Street, Suite 220
Aurora, Colorado 80014
Website URL:
http://www.pfiedlerenterprises.com
6
INTRODUCTION
Maintaining normal body temperature (ie, a core body temperature in the range of 36°C
to 38°C [96.8°F to 100.4°F]1) throughout all phases of a patient’s surgical experience is
a critical aspect of care for the perioperative nurse. One of the expected outcomes for
all patients undergoing surgical or invasive procedures is that they are at or returning
to normothermia at the conclusion of the immediate postoperative period.2 However,
unintended or unplanned perioperative hypothermia, defined as a core temperature
below 36°C (96.8°F), is one of the most common complications associated with surgical
intervention, with an incidence of up to 20%.3 The untoward effects of unintended
hypothermia and the benefits of maintaining normothermia are well documented in
the literature. Therefore, perioperative nurses should understand the importance of
maintaining normothermia in all surgical patients and implement effective measures to
prevent hypothermia and its associated adverse effects; intraoperative irrigation fluid
warming is one measure that plays a key role in achieving this outcome.
UNINTENDED PERIOPERATIVE HYPOTHERMIA: HOW AND WHY
In order to appreciate the role of irrigation fluid warming as a strategy to maintain
normothermia, the body’s thermal regulation system and characteristics of the operating
room (OR) environment that contributes to the development of hypothermia must be
reviewed.
Normal Thermal Regulation Process
Thermal regulation is the body’s physiological mechanism to balance heat production
with heat loss.4 The hypothalamus regulates body temperature in the central nervous
system by acting as a thermostat in response to temperature changes; vasoconstriction
or vasodilatation occurs to either increase or decrease the body’s temperature.5 Normal
thermoregulatory vasoconstriction maintains the core body temperature two to four
degrees warmer than the peripheral temperature of the body.6 Under normal conditions,
human thermoregulatory systems maintain a constant body temperature within a few
tenths of a degree centigrade of the normal body temperature of approximately 37°C
(98.6°F).7 In the OR, however, a combination of altered thermoregulatory mechanisms
and intrinsic and extrinsic factors typically causes a decrease in core temperature.
The Effects of Anesthesia on Thermal Regulation
Under anesthesia, the body’s normal thermoregulatory mechanisms, in particular
vasoconstriction and shivering, are inhibited; therefore, inadvertent hypothermia (ie,
a core body temperature below 36°C [96.8°F]) is a recognized side effect of general
anesthesia.8 This alteration in thermal regulation allows unwarmed patients to become
hypothermic.9 It is not unusual for a patient’s core temperature to fall below 35°C
(95°F) during anesthesia.10 While the mechanisms may differ, hypothermia also is an
unintended side effect of regional anesthesia (ie, spinal or epidural) because these
techniques alter the perception of cold in a conscious patient, thus allowing hypothermia
to go undetected.11
7
There are three phases of unplanned hypothermia, as outlined below12:
• Redistribution phase. In this phase, a rapid shift of heat from the body’s core to
the periphery occurs, resulting in a core temperature drop of approximately 1.6°C
(2.7°F) during the first hour after induction of anesthesia.13
• Linear decrease phase. The initial temperature drop that occurs in the redistribution
phase is followed by a slow linear decrease phase during the second and
subsequent hours of anesthesia; in this phase, heat loss exceeds the body’s ability
to metabolically produce heat. It is in this phase that warming the patient can
effectively limit additional heat loss.
• Thermal plateau phase. The patient’s core body temperature often plateaus after
approximately three to five hours of anesthesia. This phase is characterized
by a core body temperature that remains constant, even during longer surgical
procedures.14
Mechanisms of Heat Loss in the OR
In addition to the redistribution temperature drop outlined above, maintaining normothermia
can be a challenge in the perioperative environment because of several factors inherent to
this practice setting. These include the low ambient temperatures in the OR, skin exposure
caused by the surgical procedure and positioning requirements, exposure of internal organs,
and the use of room temperature irrigation and intravenous (IV) fluids.15
Patients lose heat to the environment through four mechanisms: radiation, convection,
conduction, and evaporation; of these, the largest contributors to heat loss are radiation and
convection.16,17 Each of these mechanisms are explained in greater detail below.
• Radiation. All surfaces that exist at a temperature above absolute zero radiate heat;
this radiated heat is absorbed by the surrounding surfaces. Therefore, the patient
radiates heat into the surrounding environment. Radiation accounts for the majority
of heat loss during surgery.
• Convection. Under normal conditions, a thin layer of stationary air next to the skin
acts as an insulator and limits conductive heat loss to surrounding air molecules.
When air currents disrupt this layer of air, its insulating properties are significantly
diminished and heat loss increases. This is referred to as convection, or the “wind
chill factor”. In non-OR hospital settings, the room air exchange rate is normally
four times per hour; in a typical OR, the air exchange occurs 15 times per hour,
which makes an OR feel subjectively colder. While surgical drapes act as thermal
insulators to minimize convective heat loss, convective heat loss is considered the
second most significant source of heat loss in the OR.
• Conduction. Conduction is the transmission of heat from one object to another,
eg, the patient’s body to a cold surface such as the OR table. The rate of heat
transfer depends on the temperature difference between the two objects and the
heat conductivity of the material. Conduction plays a minor role in heat loss during
surgery because the patient is in direct contact with the foam insulating mattress on
the OR table.
8
• Evaporation. Evaporation is the change of a liquid into a gas. This occurs at
the surface of a liquid where molecules with the highest kinetic energy are able
to escape, thus lowering the kinetic energy and decreasing the temperature.
Evaporative heat loss generally occurs when sterile skin preparation solutions are
applied, but may also occur from the operative wound.
PATIENT COMPLICATIONS OF UNINTENDED PERIOPERATIVE
HYPOTHERMIA
The combination of anesthetic-induced impairment of thermoregulatory control and
exposure to the cool OR environment makes most surgical patients hypothermic.18
Several significant patient complications associated with unintended perioperative
hypothermia are well-documented in the literature, as outlined below.
Blood Loss and Transfusion Requirements
An early study conducted by Schmied, et al, demonstrated that mild hypothermia
increases blood loss.19 Blood loss and transfusion requirements were evaluated in
60 patients undergoing primary, unilateral total hip arthroplasties; the patients were
randomly assigned to a normothermia group (defined as a final intraoperative core
temperature of 36.6°C) or a mild hypothermia group (defined as 35.0°C). Crystalloid,
colloid, scavenged red cells, and allogeneic blood were administered according to a
strict protocol. The study found that both intraoperative and postoperative blood loss
were significantly greater in the hypothermic patients: 2.2 L for the hypothermic patients
versus 1.7 L for the normothermic patients. Eight units of allogeneic packed red cells
were required in seven of the 30 hypothermic patients, whereas only one normothermic
patient required a unit of allogeneic blood. A reduction of just 1.6°C in core hypothermia
temperature increased blood loss by 500 mL (30%) and significantly increased the need
for allogeneic blood transfusion. Based on these results, the authors concluded that
maintenance of intraoperative normothermia reduces blood loss and allogeneic blood
requirements in patients undergoing total hip arthroplasty. This is important since there is
a growing body of evidence indicating that blood transfusions may be more harmful than
previously believed.20
Rajagopalan, et al, also conducted a meta-analysis and systematic review to evaluate
the hypothesis that mild perioperative hypothermia increases surgical blood loss
and transfusion requirements.21 The authors conducted a comprehensive search of
published randomized controlled trials that compared blood loss and/or transfusion
requirements in normothermic and mildly hypothermic (34°C to 36°C) surgical patients.
A total of 14 studies were included in the analysis of blood loss; 10 studies were
included in the analysis of transfusion requirements. The results demonstrated that
even mild hypothermia (<1°C) significantly increased blood loss by approximately
16% and also increased the relative risk for transfusion by approximately 22%. These
authors concluded that maintaining perioperative normothermia reduces blood loss and
transfusion requirement by clinically significant amounts.
9
Surgical Site Infection and Wound Healing
Surgical site infections (SSIs) and impaired wound infections are common and serious
complications of anesthesia and surgery.22 Today, SSIs are important clinical concerns.
According to data from the Centers for Disease Control and Prevention (CDC), in 2002
an estimated 14 million operative procedures were performed in the U.S. SSIs have
been identified as the second most common healthcare-associated infection (HAI), as
they account for 17% of all HAIs in hospitalized patients.23 A similar rate was obtained
from hospitals reporting data for 2006-2008 (15,862 SSIs following 830,748 operative
procedures) with an overall rate of nearly 2%. While advances have been made in
infection control practices, SSIs remain a substantial cause of morbidity and mortality
among hospitalized patients. In one study, among the approximately 100,000 HAIs
reported in one year, SSIs were associated with deaths in over 8,000 cases.24
It is estimated that SSIs increase postoperative hospitalization by an average of four
days and result in an increased attributable cost of $8,00025 to $25,00026 for each patient.
Hypothermia may contribute to perioperative wound infections in two ways. First, cooler
temperatures may directly impair neutrophil function; second, hypothermia may also
trigger thermoregulatory vasoconstriction.27 The subsequent reduction in cutaneous
blood flow results in subcutaneous tissue hypoxia and failure of humoral immune defense
systems to reach target areas to fight infection.
Vasoconstriction-induced tissue hypoxia may also impair wound healing.28 Scar formation
requires hydroxylation of proline and lysine residues to allow cross-linking within and
between collagen strands to provide tensile strength. The hydroxylases catalyzing this
reaction depend on oxygen; because hypothermic vasoconstriction reduces the oxygen
supply to tissues, there is a decrease in collagen deposition.
An early study conducted by Kurz, et al, examined 200 patients undergoing colorectal
surgery. The patients were randomly assigned to routine intraoperative thermal care
(ie, the hypothermia group) or additional warming (ie, the normothermia group); the
patients’ anesthetic care was standardized.29 In a double-blind protocol, their wounds
were evaluated daily until discharge from the hospital and subsequently in the clinic
after two weeks. Wounds containing culture-positive pus were considered infected. The
mean final intraoperative core temperature was 34.7°C ± 0.6°C in the hypothermia
group and 36.6°C ± 0.5°C in the normothermia group. Surgical wound infections were
found in 18 of 96 (19%) patients in the hypothermia group, but in only six of 104 (6%)
patients in the normothermia group. In addition, suture removal was delayed by one day
in the hypothermia patients and their duration of hospital stay was prolonged by 2.6 days
(approximately 20%). The authors concluded that hypothermia itself may delay healing
and predispose patients to wound infections; maintaining normothermia intraoperatively
is likely to reduce the incidence of infectious complications in patients undergoing
colorectal resection and shorten their hospital stay.
Melling, et al, also demonstrated the benefits of warming patients to reduce the incidence
of wound infection.30 In this study, 421 patients having clean surgical procedures (eg,
breast, varicose vein, or hernia) were randomly assigned to either a non-warmed (the
10
standard) group or one of two warmed groups (either local or systemic). Warming was
applied for at least 30 minutes prior to surgery. The results of this study showed 19
wound infections in 139 non-warmed patients (14%) but only 13 in the 277 patients
who received warming (5%). There was no significant difference in the development
of hematomas or seromas postoperatively, but patients in the non-warmed group were
prescribed significantly more postoperative antibiotics. The authors concluded that
warming patients before clean surgery appears to aid the prevention of postoperative
wound infection.
More recently, Hedrick, et al, who previously reported a 26% incidence of SSI in
patients undergoing elective colorectal resection, examined the effect of implementing
a multidisciplinary wound management protocol that addressed several risk
factors, including hypothermia, in reducing the incidence of SSI.31 The protocol
included maintenance of intraoperative normothermia (>36°C [96.8°F]) on patients
undergoing elective colorectal resection; the results were compared to baseline prior
to implementation of the protocol. The results demonstrated that compliance with
normothermia increased from 64% to 71%; the incidence of SSI fell from 25.6% to
15.9%. The authors concluded that, after implementation of a multidisciplinary woundmanagement protocol, the incidence of SSI improved 39%. These results demonstrate
that compliance with a prospectively designed protocol for perioperative care can
effectively reduce operative morbidity in patients undergoing colorectal procedures.
Adverse Outcomes after Off-Pump Coronary Artery Bypass Graft Surgery
Hannan, et al, performed a retrospective study of 2,294 patients who underwent off-pump
coronary artery bypass grafting to determine predictors of hypothermia and hyperthermia,
and the impact of hypothermia and hyperthermia on postoperative outcomes for off-pump
coronary artery bypass grafting.32 The patients were classified as moderately to severely
hypothermic (≤34.5°C), mildly hypothermic (34.6°C to 35.9°C), or mildly hyperthermic
(37.5°C to 38.8°C) after leaving the operating room. Significant independent predictors
of these temperature states and the independent impact of each of these states on
in-hospital mortality and complications were identified. The results showed that a total of
37.7% of patients were mildly hypothermic, 9.0% of patients were moderately to severely
hypothermic, and 5.6% of patients were mildly hyperthermic. Significant independent
predictors for postoperative hypothermia included older age, female gender, lower body
surface area, congestive heart failure, higher ventricular function, non-Hispanic ethnicity,
single/double-vessel disease, low postoperative hematocrit, previous cardiac surgery,
race other than white or black, and organ transplant. The patients with moderate to
severe hypothermia and those with mild hyperthermia had significantly higher riskadjusted in-hospital mortality than patients with normothermia. The patients with either
mild or moderate to severe hypothermia had significantly higher rates of respiratory
failure and unplanned surgical procedures. Patients with mild hyperthermia had a
significantly higher rate of respiratory failure than normothermic patients. The authors
concluded that it is important to maintain normal postsurgical core temperatures in
patients who have undergone cardiac surgery to minimize or avoid complications and
death.
11
Morbid Cardiac Events
An early randomized controlled trial conducted by Frank, et al, examined the relationship
between body temperature and morbid cardiac events (defined as unstable angina/
ischemia, cardiac arrest, or myocardial infarction) during the perioperative period.33 Three
hundred patients who either had documented coronary artery disease or were at high
risk for coronary disease undergoing non-cardiac (ie, abdominal, thoracic, or vascular)
procedures were assigned to the routine thermal care (ie, hypothermic) group or to the
additional supplemental warming care (ie, normothermic) group. The results showed
that the mean core temperature postoperatively was lower in the hypothermic group
(35.4°C ± 0.1°C) than in the normothermic group (36.7°C ± 0.1°C) and remained lower
during the early postoperative period. Perioperative morbid cardiac events occurred less
frequently in the normothermic group than in the hypothermic group (1.4% versus 6.3%,
respectively). Hypothermia was an independent predictor of morbid cardiac events, ie,
there was a 55% reduction in risk when normothermia was maintained. Postoperative
ventricular tachycardia also occurred less frequently in the normothermic group than in
the hypothermic group (2.4% versus 7.9%, respectively). The authors concluded that in
patients with cardiac risk factors who are undergoing noncardiac surgery, maintaining
perioperative normothermia is associated with a decrease in the incidence of morbid
cardiac events and ventricular tachycardia.
Prolonged Drug Effects
By decreasing drug metabolism, even mild hypothermia can lead to delayed awakening
and a prolonged length of stay in the post-anesthesia care unit (PACU).34,35 Hypothermia
alters the effects of several classes of drugs, including muscle relaxants, volatile agents,
and intravenous anesthetic agents.36,37 Both hepatic and renal blood flow are diminished
in patients with mild hypothermia, which in turn decreases metabolism and drug
excretion, respectively; this results in a decrease in plasma clearance and an increase in
drug effects.38
COSTS OF TREATING UNINTENDED HYPOTHERMIA
The patient complications resulting from the development of unintended hypothermia
cause unnecessary costs for health care facilities today.
A 1999 meta-analysis of 18 studies covering 1,575 patients identified that even mildly
hypothermic patients (ie, those whose core temperature had dropped 1.5°C below
normothermia) could experience an increase in adverse outcomes that were associated
with additional health care costs ranging from $2,500-$7,000 per patient (see Table 1).39
12
Table 1 – Cost Effectiveness Associated with Maintaining Normothermia (per
patient)40
Cost Savings
(low end)
Cost Savings
(high end)
Red blood cells (units)
$117.60
$229.43
Plasma (units)
$71.50
$76.90
Platelets (units)
$33.07
$38.07
$1,534.00
$4,602.00
Time in Intensive Care Unit (hours)
$104.75
$314.25
Wound infections
$545.40
$1,696.80
Myocardial infarction
$67.67
$90.23
Mechanical ventilation
$16.05
$25.68
Total cost savings
$2,495.11
$7,073.55
After mortality
$2,412.57
$6,839.55
Outcome
Length of hospital stay (days)
Prevention Initiatives
These additional costs of care associated with adverse patient events have significant
economic consequences as health care facilities face increasing pressure from various
initiatives to improve the quality and safety of patient care.
As of 2009, hospitals are no longer reimbursed by the Centers for Medicare and
Medicaid Services (CMS) for additional costs of care associated with certain hospitalacquired conditions, including some SSIs which CMS deems as preventable.41 The
acute-care Inpatient Prospective Payment System final rule, which updated Medicare
payments to hospitals for fiscal year 2009, provided additional incentives for health care
facilities to improve the quality of care provided to Medicare patients by the inclusion
of payment provisions to reduce preventable medical errors. In particular, if certain
conditions are not present upon admission, but are acquired during the course of the
patient’s hospital stay, Medicare no longer pays the additional costs of the hospitalization
and care; in addition, the patient is not responsible for these costs and cannot be billed.
Many private insurers followed this payment policy. CMS issued a final rule that updated
fiscal year 2012 payment policies and rates for hospitals on August 1, 2011, as part of
the 2010 Affordable Care Act. This rule continues the payment approach that incentivizes
hospitals to adopt practices that reduces errors and prevents patients from acquiring new
illnesses or injuries during a hospital stay.42
As noted above, SSIs are common healthcare-associated infections (HAIs) today
and represent one of the leading causes of postoperative morbidity and mortality and
additional unplanned costs of care. Therefore, the Surgical Care Improvement Project
(SCIP), sponsored by CMS in collaboration with a number of other national partners,
13
continues to focus on measures to reduce SSIs.43 The 2013 National Prevention Target
is 95% adherence to process measures that prevent SSI, eg, appropriate prophylactic
antibiotic administration and discontinuation; postoperative serum glucose level for
cardiac surgery patients, and hair removal for surgery patients. Preventing HAIs and
SSIs also continues to be a focus of The Joint Commission.44 Goal seven of the 2013
Joint Commission National Patient Safety Goals is to reduce the risk of HAIs and SSIs
by compliance with current hand hygiene guidelines and implementing evidence-based
prevention practices.
THE ROLE OF INTRAOPERATIVE IRRIGATION FLUID WARMING IN
HYPOTHERMIA PREVENTION
As demonstrated in the clinical studies cited above, unplanned perioperative hypothermia
is now widely recognized as a preventable cause of many complications and adverse
reactions in surgical patients, which not only impact patient safety, but also impose
significant financial consequences.45 Therefore, perioperative nurses should implement
effective strategies to prevent this avoidable surgical complication.46 While there are
several modalities available today for maintaining normothermia in surgical patients, this
discussion will focus on the role of warmed irrigation fluid in preventing hypothermia.
Professional Nursing Guidelines
Two professional nursing organizations support the use of warmed irrigation solutions to
prevent unintended perioperative hypothermia.
• The Association of periOperative Registered Nurses (AORN) Recommended
Practices for the Prevention of Unplanned Perioperative Hypothermia47 state
that interventions should be implemented to prevent unplanned perioperative
hypothermia. These recommendations include the use of warmed irrigation fluid
(near 37°C [98.6°F]) inside the abdomen, pelvis, or thorax as an adjunct therapy
to reduce heat loss. When using warmed irrigation fluids, to prevent patient injury,
the temperature of the solution should be measured with a thermometer at the
point of use and verified prior to instillation.
• The American Society of PeriAnesthesia Nurses (ASPAN) Evidence-Based
Clinical Practice Guideline for the Promotion of Perioperative Normothermia48
also cites there is evidence that warmed irrigation fluids, when used alone or in
combination with forced-air warming, may maintain normothermia.
Clinical Studies: Benefits of Warmed Irrigation Fluids
The benefits of using warmed irrigation fluids in preventing hypothermia across multiple
surgical specialties are also well documented in clinical literature.
Recently, Jin, et al, conducted a systematic review of randomized controlled trials to
establish whether warmed irrigation fluid temperature could reduce the drop in body
temperature and the incidence of shivering and hypothermia in patients undergoing
endoscopic procedures; this review included 13 studies with 686 patients.49 The results
demonstrated that the use of room temperature irrigation fluid caused a greater drop in
14
core body temperature in patients, compared to the use of warmed irrigation fluid. The
occurrence of shivering and hypothermia was also lower in the patients who received
warmed irrigation fluid than those patients who received room temperature fluid. The
investigators concluded that in endoscopic surgical procedures, irrigation fluid should be
warmed in order to decrease the drop in core body temperature and reduce the risk of
perioperative shivering and hypothermia; furthermore, warming irrigating fluid should be
considered standard practice in all endoscopic surgeries.
Mirza, et al, conducted a prospective observational study of 100 patients undergoing
various types of endoscopic urological procedures (eg, cystoscopies, transurethral
resection of the prostate [TURP], transurethral resection of a bladder tumor [TURBT]
percutaneous nephrolithotomy [PCNL]) to determine the temperature difference
between preoperative and postoperative core temperatures and also to establish if this
change was related to patient age, weight, type of anesthetic, type and duration of the
procedure, amount of irrigation fluid used, and if warming the irrigation fluid to 37°C
made a difference in the degree of core temperature change.50 The highest degree of
temperature drop was seen in the patients in the PCNL group. There was a significant
relationship between the duration of the procedure and the temperature drop and also
the amount of irrigation fluid used. The mean temperature drop for patients who received
irrigation fluid at room temperature (43 patients) was 1.37°C and 0.95°C for those
patients who received fluids that were warmed to body temperature (57 patients). This
temperature difference is statistically significant. These authors concluded that there
is a decrease in temperature in patients undergoing most genitourinary endoscopic
procedures; the cause appears to be multifactorial in origin, relating significantly to
weight, amount of irrigation fluid used, and the type and duration of the operation.
Warming irrigation fluid to body temperature appears to significantly reduce the degree of
core temperature drop and consequently has potential benefits.
Kim, et al, evaluated the effect of irrigation fluid temperature on body temperature and
other variables in a prospective randomized study of 50 patients undergoing arthroscopic
shoulder surgery who received irrigation fluid either at room temperature or warmed to
37°C to 39°C.51 Core body temperature was checked at regular intervals and additional
variables, such as length of anesthesia and surgery, amount of irrigation fluid and
intravenous fluid used, amount of bleeding, weight gain, and postoperative pain were
collected intraoperatively and postoperatively. The results demonstrated that the final
core body temperature was 35.5°C ± 0.3°C in the room temperature fluid group and
36.2°C ± 0.3°C in the warmed fluid group. The temperature drop was 0.86°C ± 0.2°C
in the room temperature fluid group and 0.28°C ± 0.2°C in the warmed fluid group.
Hypothermia occurred in 91.3% of patients in the room temperature fluid group; whereas
the incidence of hypothermia was only 17.4% in the warmed fluid group. Of the variables
measured, the patient’s age and amount of irrigation fluid used correlated with core body
temperature in the room temperature fluid group; no variables correlated with core body
temperature in the warmed fluid group. The authors concluded that hypothermia occurred
more often in shoulder arthroscopic surgery when room temperature fluid is used for
irrigation than with warmed fluid irrigation. The patient’s age and amount of irrigation
fluid used correlate with core body temperature when using room temperature irrigation
15
fluid. The use of warm irrigation fluid during arthroscopic shoulder surgery decreases
perioperative hypothermia, especially in elderly patients.
An earlier study conducted by Board and Srinivasan designed to investigate the
relationship between irrigation fluid temperature and core body temperature in patients
undergoing arthroscopic shoulder surgery demonstrated similar results.52 Twentyfour consecutive patients undergoing arthroscopic subacromial decompression were
assigned to receive irrigation fluid at either room temperature (22°C) or warmed to 36°C.
There were no statistically significant differences between the two groups in any of the
preoperative parameters. Core temperature was monitored throughout the procedure; the
maximum drop in core temperature for each patient was calculated. The results showed
that the mean maximum drop in core temperature was 1.67°C in the room temperature
fluid group and 0.33°C in the warmed fluid group. Additionally, the drop in core
temperature in the room temperature fluid group persisted throughout surgery and only
normalized postoperatively; however, the drop in the warmed fluid group was transient,
with core body temperature stabilizing after 30 minutes in most cases. Two patients in
the room temperature fluid group were noted to suffer from severe shivering during the
immediate postoperative period. The authors concluded that, since core temperature
may be affected by the temperature of the irrigation fluid, all arthroscopic shoulder
surgeries should be performed with irrigation fluid warmed to 36°C.
Procedures Which Benefit Using Warm Fluid
Warm irrigation solutions may be beneficial to patients in preventing hypothermia in
many surgical specialties, ie, not only in large, open abdominal procedures, but for labor
and delivery, ENT, neonatal, and neurosurgery procedures as well. The use of warmed
irrigation fluid has been shown to decrease the drop in core temperature in patients
undergoing laparoscopic surgery.53
Irrigation Fluid Warming: Methods and Best Practices
When using warmed irrigation solution, it is important that it is at the “right” temperature
at the time of use during the surgical procedure (see Figure 1) to minimize the risk for
patient injury.
Risks to patient safety can occur when irrigation fluid is either colder (risk of low core
temperatures and hypothermia) or too hot (risk of patient burn, tissue damage).
1 – Patient
Associated
Irrigation
Temperature
FigureFigure
1 – Patient
RisksRisks
Associated
WithWith
Irrigation
FluidFluid
Temperature
Normothermia
Risk of Hypothermia
Risk to Patient Safety
There are three methods for warming irrigation fluid. Each of these is described in greater detail below
1. Saline bottles in a cabinet warmer,
16
2. Closed fluid warming systems, and
There are three methods for warming irrigation fluid. Each of these is described in greater
detail below:
1. Saline bottles in a cabinet warmer,
2. Closed fluid warming systems, and
3. Open basin active warming systems.
1. Saline bottles in a cabinet warmer (see Figure 2). Solution bottles for irrigation
and blankets should be stored in separate warming cabinets. ECRI recommends
that the temperature of solution warming cabinets should be limited to 110°F
(43.3°C), as temperatures above this level unnecessarily increase the risk of
burns and pose a patient safety risk.54 AORN recommends that the solutionwarming cabinet temperatures should be limited to the specifications provided
by the solution manufacturer; additionally, the cabinet temperature should
be routinely monitored and documented on a temperature log or on a record
provided by an electronic recording system, according to facility policy.55
Figure 2 – Example Fluid Warming Cabinet
However, storing saline bottles in a warming cabinet is not really that simple.
Because irrigation fluid is considered a “medication” and saline has a limited
lifespan once placed in the warmer, the solution bottles must be labeled and
rotated in the cabinet. Some of the specific guidelines are:
◦◦ Limit storage of bottles from three to 30 days at elevated temperature,
depending on the saline brand;
◦◦ Label each bottle with an expiration date and discard after this date; and
◦◦ Do not put bottles back into cabinet after they are already warmed.
The AORN Recommended Practices also state that fluids kept in warmers should
be labeled with the date they should be removed or the date on which they are
placed in the warmer; solutions should be rotated on a first-in, first-out basis.56
17
The advantages of using saline warmed in cabinet warmers include:
◦◦ The relatively low cost to maintain after capital purchase; and
◦◦ That warm bottles of saline are readily available for use.
The disadvantages include:
◦◦ The space and location concerns;
◦◦ Staff time is required to label and rotate saline inventory and routinely
monitor cabinet temperatures; and
◦◦ The need to pull a bottle out of the warming cabinet close to the time of
use. Overall, this is not an efficient use of nursing resources. Other safety
considerations include:
▪▪ Possible changes in saline composition (more hypertonic, ie, higher
salt content) under extended heat, and
▪▪ Cabinet warmers can “melt” the saline bottles under prolonged heat.
Microwaves or autoclaves cannot guarantee a known or safe fluid temperature
and therefore, should not be used to warm irrigation solutions.57
Another concern with this method is that even bottles taken from a warming
cabinet cool down quickly over time. It takes approximately seven minutes for a
bottle of fluid to cool down to room temperature after it has been taken from the
cabinet warmer. In addition, fluids that are too hot can risk injury, and those that
are too cold can risk hypothermia. Therefore, there is a very short time window of
five to seven minutes during which the fluid temperature is appropriate for use.
2. Closed irrigation fluid warming systems (see Figure 3). This type of system
warms the fluid as it is being delivered to the patient. Its advantages include:
◦◦
◦◦
◦◦
◦◦
The temperature of the fluid can be set and validated;
Standard size IV bags can often be used;
The irrigation fluid is under pressure; and
The fluid is warmed quickly.
Closed irrigation systems are typically used when using large volumes of solution,
and delivery of the fluid must be under pressure to deliver precise volumes to
a small surgical site, as with laparoscopic surgeries. Unlike open fluid warming
systems, the method of closed irrigation systems do not allow cleaning the
surgical site or tissues with sponges, or washing the surgical site using a basin,
graduate, or container filled with fluid.
18
Figure 3 – Example of Closed Irrigation Fluid Warming System
Considerations for use include that this type of system is typically used for
procedures requiring large volumes of fluid or laparoscopic procedures; single
patient use tubing sets are required; and regular maintenance and/or calibration
of equipment may be required.
3. Open irrigation fluid warming system (see Figure 4). An open irrigation fluid
warming system warms the fluid in an open basin, similar in practice to an open
basin on a ring stand, only the warming system provides immediate access to
warm irrigation fluid within the sterile field at a visible and controlled temperature.
Figure 4 – Example Open Irrigation Fluid Warming System
The advantages of this type of system include:
◦◦ It eliminates the need for labelling and rotating saline bottle inventory, which
is more efficient use of nursing time and effort.
19
◦◦ The visible display confirms the temperature of the fluid at the time of
delivery of the fluid to the patient. This eliminates the guesswork of nurses
and surgeons trying to determine the “right temperature” of the fluid with
their hands.
◦◦ The temperature setting can be adjusted and “locked” with an accuracy of
±2°F.
◦◦ Immediate access to continuously warmed irrigation fluid, at a verifiable
temperature, is superior to using fluid warmed in a cabinet, as this practice
reduces the risk of patient burns from hot solutions or the risk of inadvertent
hypothermia from solutions that have cooled down.
▪▪ An early study by Harioka, et al, showed that the use of a continuously
warmed irrigation system could prevent a decrease in body
temperature in patients undergoing transurethral resection of bladder
and prostate tumors under spinal anesthesia.58
▪▪ A case report of an accidental burn during routine knee arthroscopy
due to use of hot irrigation fluid suggested that the temperature of any
warmed arthroscopic irrigation fluid should be checked before and
during its use, since a warming cabinet may have a wide range of
temperatures within it despite an external thermometer and possibly
an unreliable temperature setting mechanism.59
◦◦ The perioperative nurse can control and document fluid temperature in the
sterile field, which assures optimal temperature in order to:
▪▪ Minimize the risk for injury due to hot fluids;
▪▪ Improve patient safety and outcomes (eg, reducing the risk for costly
SSIs);
▪▪ Comply with the AORN recommendations for temperature control and
verification of fluid temperature before installation; and
▪▪ Achieve the goals of CMS, SCIP, and The Joint Commission in
reducing SSIs.
Considerations for use include that the system needs to be started during room
set up and covered with sterile drapes, as seen in Figure 4.
The key advantages and considerations for use of the three fluid warming
methods are summarized in Table 2.
20
Table 2 – Summary of Fluid Warming Methods
Advantages
Method 1: Saline Bottles in Warming Cabinets
Considerations
• Readily available supply of warmed fluids
• Relatively low cost to maintain
• Limited lifespan of warmed saline bottles
• Possible changes in saline composition
• Warmed saline bottles cool down quickly
over time
• Saline bottles can “melt” under prolonged
heat
• Space and location concerns
• Inefficient use of staff time in pulling bottles
at time of use, labeling and rotating saline
inventory, routinely monitoring cabinet
temperatures
Method 2: Closed Irrigation Fluid Warming Systems
•
•
•
•
Fluid temperature can be set and validated
Standard size IV bags can typically be used
Irrigation fluid is under pressure
Fluid is warmed quickly
• Used for large volumes of solution, when
fluid must be under pressure to deliver
precise volumes to a small surgical site (eg,
with laparoscopic surgeries)
• Does not allow easy cleaning of the surgical
site with sponges, or irrigating the surgical
site using a basin, graduate, or container
filled with warm fluid
• Single patient use tubing sets are required
• Regular maintenance and/or calibration of
equipment may be required
Method 3: Open Irrigation Fluid Warming Systems
• Fluid is warmed in an open basin, similar in practice to
an open basin on a ring stand
• Provides immediate access to warm irrigation fluid
within the sterile field at a visible and controlled
temperature
• Eliminates the need for labelling and rotating saline
bottle inventory
• Visible display confirms the temperature of the fluid at
the time of delivery to the patient
• Temperature setting can be adjusted and “locked” with
an accuracy of ±2°F
• Reduces the risk of patient burns from hot solutions or
the risk of inadvertent hypothermia from solutions that
have cooled down
• Nurses can control and document fluid temperature in
the sterile field, which assures optimal temperature in
order to:
• Minimize the risk for injury due to hot fluids
• Improve patient safety and outcomes
• Comply with the AORN recommendations for
temperature control and verification of fluid
temperature before instillation
• Achieve the goals of CMS, SCIP, and The Joint
Commission in reducing SSIs
21
• System needs to be started during room set
up and covered with sterile drapes
SUMMARY
Unintended perioperative hypothermia is defined as a core temperature less than 36.0°C
(96.8°F) and is a common consequence of anesthesia and surgical intervention. The
untoward effects of unintended hypothermia and the benefits of preventing even mild
hypothermia are well documented in the literature. Therefore, maintaining normothermia
throughout a patient’s surgical experience is a critical aspect of perioperative nursing
care. There are a number of interventions available today that allow the prevention of
perioperative hypothermia to be an obtainable goal. The use of warmed irrigation fluids
is one measure that can be implemented to decrease the incidence of unintended
perioperative hypothermia. Furthermore, immediate access to continuously warmed
irrigation fluid is superior to using fluid warmed in a cabinet, as this practice reduces the
risk of patient burns from solutions that may be too hot or hypothermia from solutions
that are too cool. Through an increased awareness of the role of irrigation fluid warming
in maintaining normothermia, perioperative nurses can reduce the risk for the adverse
outcomes and additional costs of care associated with unintended perioperative
hypothermia, thereby promoting positive patient outcomes.
22
GLOSSARY
Ambient Temperature
The temperature of the immediate environment;
in the OR, the temperature should be maintained
between 20°C to 23°C (68°F to 73°F).
Conduction
The transmission of heat from one object to another,
eg, the patient’s body to a cold surface such as the
OR table; the rate of heat transfer depends on the
temperature difference between the two objects and
the heat conductivity of the material.
Convection
The loss of heat as cold air moves across the thin
layer of stationary air next to the skin; also referred
to as the “wind chill factor”.
Core Body Temperature
The temperature of the thermal compartment of the
body, which contains the highly perfused tissues and
major organs, as compared to the temperature of
peripheral tissues.
Evaporation
The change of a liquid into a gas. Evaporative heat
loss occurs when sterile skin preparation solutions
are applied, but may also occur from the operative
wound.
Healthcare-Associated
Infection (HAI) An infection acquired by patients during
hospitalization, with confirmation of diagnosis
by clinical or laboratory evidence. The infective
agents may originate from endogenous or
exogenous sources. HAIs, which are also
known as nosocomial infections, may not become
apparent until the patient has been discharged
from the hospital.
Hypothermia
A core body temperature less than 36°C (96.8°F).
Mild Hypothermia
A core body temperature between 34°C to 36°C
(93.2°F to 96.8°F).
Normothermia
A core body temperature between 36°C to 38°C
(96.8°F to 100.4°F).
Radiation
The transfer of heat from the patient’s body to the
colder environment in the form of radiant energy.
23
Redistribution Hypothermia
A decrease in body temperature occurring as heat
is exchanged from the body’s core compartment
to the peripheral tissues.
Surgical Site Infection (SSI)
An infection occurring at the site of a surgical
incision. The infection may be superficial, deep, or
may extend to organs.
Unintended Perioperative
Hypothermia An unexpected core temperature decrease to
less than 36°C (96.8°F) as a result of surgery.
24
REFERENCES
1. Hegarty J, Walsh E, Burton A, Murphy S, O’Gorman F, McPolin G. Nurses’
knowledge of inadvertent hypothermia. AORN J. 2009;89(4):707-713.
2. Normothermia. In: Petersen C, ed. Perioperative Nursing Data Set: The
Perioperative Nursing Vocabulary, 3rd ed. Denver, CO: AORN, Inc.; 2011: 277.
3. Kurz A. Physiology of thermoregulation. Best Pract Res Clin Anaesthesiol.
2008;22(4):627-644.
4. Lynch S, Dixon J, Leary D. Reducing the risk of unplanned perioperative
hypothermia. AORN J. 2010; 92 (5):553-562.
5. Weirich TL. Hypothermia/warming protocols: why are the not widely used in the
OR? AORN J. 2008;87(2): 333-344.
6. Sessler DI. Mild perioperative hypothermia. New Engl J Med. 1997; 336(24):17301737.
7. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
8. Sessler DI. Mild perioperative hypothermia. New Engl J Med. 1997; 336(24):17301737.
9. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
10. Scott EM, Buckland R. A systematic review of intraoperative warming to prevent
postoperative complications. AORN J. 2006; 83(5): 1090-1113.
11. Scott EM, Buckland R. A systematic review of intraoperative warming to prevent
postoperative complications. AORN J. 2006; 83(5): 1090-1113.
12. AORN. Recommended practices for the prevention of unplanned perioperative
hypothermia. In: Perioperative Standards and Recommended Practices. Denver,
CO: AORN, Inc.; 2013: 375-386.
13. Matsukawa T, Sessler DI, Sessler AM, et al. Heat flow and distribution during
induction of general anesthesia. Anesthesiology. 1995;82(3):662-673.
14. Sessler DI. Perioperative heat balance. Anesthesiology. 2000;92(2): 578-596.
15. Lynch S, Dixon J, Leary D. Reducing the risk of unplanned perioperative
hypothermia. AORN J. 2010; 92(5): 553-562.
16. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
17. Sessler DI. Temperature regulation and monitoring. In: Miller RD, Eriksson LI,
Fleisher LA, Wiener-Kronish JP, eds. Miller’s Anesthesia. 7th ed. Philadelphia, PA:
Churchill Livingstone/Elsevier; 2010:1533-1536.
25
18. Reynolds L, Beckmann J, Kurz A. Perioperative complications of hypothermia. Best
Pract Res Clin Anaesthesiol. 2008;22(4): 645-657.
19. Schmied H, Kurz A, Sessler DI, Kozek S, Reiter A. Mild intraoperative hypothermia
increases blood loss and allogeneic transfusion requirements during total hip
arthroplasty. Lancet. 1996; 347(8997): 289–292.
20. Reynolds L, Beckmann J, Kurz A. Perioperative complications of hypothermia. Best
Pract Res Clin Anaesthesiol. 2008;22(4): 645-657.
21. Rajagopalan S, Mascha E, Na J, Sessler DI. The effects of mild perioperative
hypothermia on blood loss and transfusion requirement. Anesthesiology. 2008;
108(1):71–77.
22. Reynolds L, Beckmann J, Kurz A. Perioperative complications of hypothermia. Best
Pract Res Clin Anaesthesiol. 2008;22(4): 645-657.
23. CDC. Surgical site infection (SSI) event. http://www.cdc.gov/nhsn/pdfs/
pscmanual/9pscssicurrent.pdf. Accessed January 10, 2013.
24. CDC. Surgical site infection (SSI) event. http://www.cdc.gov/nhsn/pdfs/
pscmanual/9pscssicurrent.pdf. Accessed January 10, 2013.
25. Dimick JB, Chen SL, Taheri PA, Henderson WG, Khuri SF, Campbell DA Jr. Hospital
costs associated with surgical complications: a report from the private-sector National
Surgical Quality Improvement Program. J Am Coll Surg. 2004;199(4): 531-537.
26. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
27. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
28. Reynolds L, Beckmann J, Kurz A. Perioperative complications of hypothermia. Best
Pract Res Clin Anaesthesiol. 2008;22(4): 645-657.
29. Kurz A, Sessler DI, Lenhardt R. Perioperative normothermia to reduce the incidence
of surgical-wound infection and shorten hospitalization. Study of Wound Infection and
Temperature Group. N Engl J Med. 1996;334(19): 1209-1215.
30. Melling AC, Ali B, Scott EM et al. Effects of preoperative warming on the incidence
of wound infection after clean surgery: a randomised controlled trial. Lancet. 2001;
358(9285): 876–880.
31. Hedrick TL, Heckman JA, Smith RL, Sawyer RG, Friel CM, Foley EF. Efficacy of
protocol implementation on incidence of wound infection in colorectal operations. J
Am Coll Surg. 2007; 205(3):432-438.
32. Hannan EL Samadashvili Z, Wechsler A, et al. The relationship between perioperative
temperature and adverse outcomes after off-pump coronary artery bypass graft
surgery. J Thorac Cardiovasc Surg. 2010;139(6):1568-1575.
26
33. Frank SM, Fleisher LA, Breslow MJ, et al. Perioperative maintenance of
normothermia reduces the incidence of morbid cardiac events. A randomized
clinical trial. JAMA. 1997;277(14):1127-1134.
34. Bissonnette B, Sessler DI. Mild hypothermia does not impair postanesthetic
recovery in infants and children. Anesth Analg. 1993;76(1):168-172.
35. Lenhardt R, Marker E, Goll V, et al. Mild intraoperative hypothermia prolongs
postanesthetic recovery. Anesthesiology. 1997;87(6): 1318-1323.
36. Leslie K, Sessler DI, Bjorksten AR, Moayeri A. Mild hypothermia alters propofol
pharmacokinetics and increases the duration of action of atracurium. Anesth Analg.
1995;80(5):1007-1014.
37. Heier T, Caldwell JE, Sessler DI, Miller RD. Mild intraoperative hypothermia
increases duration of action and spontaneous recovery of vecuronium
blockade during nitrous oxideisoflurane anesthesia in humans. Anesthesiology.
1991;74(5):815-819.
38. Hart SR, Bordes B, Hart J, Corsino D, Harmon D. Unintended perioperative
hypothermia. Ochsner J. 2011;11(3):259-270.
39. Mahoney CB, Odom J. Maintaining intraoperative normothermia: a meta-analysis
of outcomes with costs. AANA J. 1999;67(2):155-164.
40. Mahoney CB, Odom J. Maintaining intraoperative normothermia: a meta-analysis
of outcomes with costs. AANA J. 1999;67(2):155-164.
41. CMS. Medicare and Medicaid move aggressively to encourage greater patient
safety in hospitals and reduce never events. http://www.cms.gov/apps/media/
press/release.asp?Counter=3219&intNumPerPage=10&checkDate=&checkKey=&
srchType=1&numDays=3500&srchOpt=0&srchData=&keywordType=All&chkNews
Type=1%252C+2%252C+3%252C+4%252C+5&intPage=&showAll=&pYear=&yea
r=&desc=false&cboOrder=date. Accessed January 10, 2013.
42. HAI focus. CMS issues Medicare final payment rule; strengthens tie between
payment and quality improvement. http://haifocus.com/cms-issues-medicarefinal-payment-rule-strengthens-tie-between-payment-and-quality-improvement/.
Accessed January 10, 2013.
43. U.S. Department of Health and Human Services. National targets and metrics.
http://www.hhs.gov/ash/initiatives/hai/nationaltargets/index.html#scip. Accessed
January 10, 2013.
44. The Joint Commission. National Patient Safety Goals. Effective January 1, 2013.
http://www.jointcommission.org/assets/1/18/NPSG_Chapter_Jan2013_HAP.pdf.
Accessed January 10, 2013.
45. Hooper VD, Chard R, Clifford T, et al. ASPAN’s evidence-based clinical practice
guideline for the promotion perioperative normothermia. J PeriAnesth Nurs.
2009;24(5):271-287.
27
46. Lynch S, Dixon J, Leary D. Reducing the risk of unplanned perioperative
hypothermia. AORN J. 2010; 92(5): 553-562.
47. AORN. Recommended practices for the prevention of unplanned perioperative
hypothermia. In: Perioperative Standards and Recommended Practices. Denver,
CO: AORN, Inc.; 2013: 375-386.
48. Hooper VD, Chard R, Clifford T, et al. ASPAN’s evidence-based clinical practice
guideline for the promotion of perioperative normothermia. J Perianesth Nurs.
2009:24(5):271-287.
49. Jin Y, Tian J, Sun M, Yang K. A systematic review of randomised controlled trials of
the effects of warmed irrigation fluid on core body temperature during endoscopic
surgeries. J Clin Nurs. 2011;20(3-4):305-316.
50. Mirza S, Panesar S, AuYong KJ, French J, Jones D, Akmal S. The effects of
irrigation fluid on core temperature in endoscopic urological surgery. J Perioper
Pract. 2007;17(10):494-497, 499-503.
51. Kim YS, Lee JY, Yang SC, Song JH, Hoh HS, Park WK. Comparative study of the
influence of room-temperature and warmed fluid irrigation on body temperature in
arthroscopic shoulder surgery. Arthroscopy. 2009;25(1):24-29.
52. Board TN, Srinivasas MS. The effect of irrigation fluid temperature on core body
temperature in arthroscopic shoulder surgery. Arch Orthop Trauma Surg. 2008;
128:531–533.
53. Moore SS, Green CR, Wang FL, Pandit SK, Hurd WW. The role of irrigation in the
development of hypothermia during laparoscopic surgery. Am J Obstet Gynecol.
1997; 176(3):598-602.
54. ECRI Institute. Warming cabinets. https://www.ecri.org/Documents/RM/HRC_TOC/
SurgAn23ES.pdf. Accessed January 10, 2013.
55. AORN. Recommended practices for a safe environment of care. In: Perioperative
Standards and Recommended Practices. Denver, CO: AORN, Inc.; 2013: 217-242.
56. AORN. Recommended practices for a safe environment of care. In: Perioperative
Standards and Recommended Practices. Denver, CO: AORN, Inc.; 2013: 217-242.
57. Fogg D. Clinical issues. Absorbable hemostatic agents; transporting sterile
instruments; alcohol-based hand rubs; microwave warming of fluid. AORN J. 2004;
80(1): 122-128.
58. Harioka T, Murakawa M, Noda J, Mori K. Effect of continuously warmed irrigating
solution during transurethral resection. Anaesth Intensive Care. 1988;16 (3):324328.
59. Huang S, Gateley D, Moss AL. Accidental burn injury during knee arthroscopy.
Arthroscopy. 2007; 23(12):1363.e1-3.
28
Please click here for the
Post-Test and Evaluation
29