Chapter 66: Nursing Management Critical CareCritical Care
Nursing Critical Care/Intensive Care Units PICU any type of
pediatric intensive care patient except cardiac NICU infant that
has to have never left the hospital Critical Care Nurse Performs
frequent assessments to monitor trends in patients physiologic
parameters (BP, ECG, etc.) Provides psychologic support to patient
and caregiver(s) Important to be skilled in palliative and
end-of-life care Certifications critical care nurses can get
Critical Care Certification (CCRN) Progressive Care Certification
(PCCN) Cardiac Medicine (CMC) Cardiac Surgery (CSC) Nurses should
be aware of the scope of practice provided by their state's Nurse
Practice Act In general, nurses can provide Patient and caregiver
teaching about an illness or disease The general course of illness
What usual treatment entails Diagnosis and prognosis are outside
the scope of practice for a registered nurse Critical Care Patient
Common Problems of Critical Care Patients Usually immobile and at
high risk for thromboembolism and skin problems Use of multiple
invasive devices predisposes patient to hospital-acquired
infections Sepsis and multiple organ dysfunction (MODS) may follow
Nutrition Must collaborate with physician and dietician to
determine how to meet nutritional needs Primary goal is to prevent
or correct nutritional deficiencies Usually accomplished with
Enteral (calories via GI tract) and Parenteral (calories via IV)
nutrition Enteral nutrition is usually encouraged Preserves the
structure and function of the gut mucosa Prevents the movement of
gut bacteria across the intestinal wall and into the bloodstream In
addition, early enteral nutrition is associated with fewer
complications and shorter hospital stays, and is less expensive
than parenteral nutrition Parenteral nutrition is used when Enteral
route is unsuccessful or contraindicated Paralytic ileus, diffuse
peritonitis, intestinal obstruction, pancreatitis, GI ischemia,
intractable vomiting, and severe diarrhea Anxiety Encourage
patients and caregivers to express concerns, ask questions, and
state their needs Include patient & caregiver in all
conversations and explain purpose of equipment & procedures
Structure patient's surrounding environment in a way that decreases
anxiety For example, encourage caregivers to bring in photographs
and personal items Judicious use of antianxiety drugs (e.g.,
lorazepam [Ativan]) and complementary therapies (e.g., guided
imagery, massage) may reduce stress response that can be triggered
by anxiety Pain Control of pain is paramount as many as 70% in ICU
have moderate to severe uncontrolled pain ICU patients at high risk
for pain include patients who Have medical conditions that include
ischemic, infectious, or inflammatory processes Are immobilized
Have invasive monitoring devices, including endotracheal tubes
Require invasive or noninvasive procedures If giving Propofol for
sedation, a daily sedation vacation (interruption of sedation)
should be conducted allows patient to wake so a neurological
assessment can be done Patients who are intubated can feel pain
(could be grimacing or show change in vitals) If doing a dressing
change, should give them prophylactic pain meds Impaired
communication Some patients may not be able to speak b/c of the use
of sedative and paralyzing drugs or an endotracheal tube Always
explain what will happen or is happening to the patient when doing
any procedure Explore using picture boards, notepads, magic slates,
or computer keyboards if they cant talk Look directly at patient
when speaking to them and use gestures when appropriate Comfort
touch is important to some patients Encourage caregivers to touch
and talk with the patient even if patient is unresponsive or
comatose Sensory-Perceptual Problems Estimated that the prevalence
of delirium in ICU patients is as high as 80% Factors Predisposing
Patient to Delirium Demographic factors advanced age, preexisting
cognitive impairment, vision/hearing impairments, history of drug
or alcohol abuse Environmental factors sleep deprivation, anxiety,
sensory overload, immobilization Physical conditions hemodynamic
instability, hypoxemia, hypercarbia, electrolyte disturbances,
severe infections Certain drugs sedatives, Lasix, antimicrobials
Must address physiologic factors (e.g. correct O2 levels,
perfusion, and electrolyte problems) Use of clocks and calendars
can help orient patient Presence of caregiver may help orient
patient and reduce agitation Neuroleptic drugs (Haldol) can be used
if patient demonstrates hyperactivity, insomnia, delusions Limit
noise and explain noises that cannot be prevented Have
conversations out of patient area unless involving patient in
conversation Silent unnecessary alarms while doing procedures then
reactivate them when done Sleep Problems Nearly all patients in ICU
experience sleep disturbances significant stressor in ICU
Contributes to delirium and possibly affects recovery Structure
environment to promote patients sleep-wake cycle Cluster activities
Schedule rest periods Dim lights at nighttime Open curtains during
the daytime Obtain physiologic measurements w/o disturbing patient
Limit noise Provide comfort measures (e.g. back rubs) Many patients
on sleep aids to induce/maintain sleep benzos (Restoril) &
benzo-like (Ambien) Issues Related to Caregivers To be effective in
caring for their loved one, caregivers need your guidance and
support Caregivers experience anxiety regarding patients condition,
prognosis, pain and other discomforts, and finances If anxious
about finances, consulting with case manager or social worker is
helpful Nurses must provide family-centered care need skills in
crisis intervention Interventions active listening, reduction of
anxiety, support of those who become upset or angry, acknowledgment
of caregivers feelings and acceptance of their decisions, meeting
informational, reassurance, and convenience needs Note: patients
often exhibit early and subtle signs of deterioration (e.g. mild
confusion, tachycardia) 6-8 hours before cardiac and/or respiratory
arrest
Drugs Related to Critical Care Dopamine Increases contractility
of the heart CO is increased Renal dose will open up the kidney
function and helps increase urine output At higher levels, blood
pressure is increased and renal perfusion is decreased Dobutamine
Helps the heart pump efficiently Use in cardiogenic shock Levophed
Vasoconstriction, which helps increase blood pressure Long-term use
can cause necrosis of the extremities fingers, toes, etc.
Nitroglycerin Vasodilation, which relieves chest pain Can give the
patient a severe headache usually will give them Tylenol as well
Propofol Sedation Also helps for nausea leaves the body very
quickly so it does not help the nausea for long Can drop BP quickly
Two Types Regular Nut based watch for nut allergies to avoid
anaphylaxis Prescedex Sedation Epinephrine Low BP, allergic
reaction Norepenephrine/Levophed Shunt the blood to vital organ
extremities are effected the most Amiodorone Antidysmic
Hemodynamic Monitoring Measurement of pressure, flow, and
oxygenation within the cardiovascular system Invasive monitoring
internally placed devices Noninvasive monitoring external devices
Values Commonly Measured in the ICU Systemic and pulmonary arterial
pressures Central venous pressure (CVP) Pulmonary artery wedge
pressure (PAWP) (also known as pulmonary artery occlusive pressure
[PAOP]) CO/CI SV/SV index [SVI] O2 saturation of the hemoglobin of
arterial blood (SaO2) Mixed venous oxygen saturation (SvO2) These
measurements allow you to calculate Resistance of the systemic and
pulmonary arterial vasculature O2 content, delivery, and
consumption Hemodynamic Terminology Cardiac Output volume of blood
in liters pumped by the heart in 1 minute Cardiac Index measurement
of CO adjusted for body surface area (BSA) More precise measurement
of the efficiency of the pumping action of the heart Preload volume
in ventricle at the end of diastole Afterload forces opposing
ventricular ejection Systemic arterial pressure, resistance by
aortic valve, and mass and density of the blood to be moved WANT TO
LOOK AT SVR IN REGARDS TO AFTERLOAD (systemic vascular resistance)
Systemic Vascular Resistance resistance of the systemic vascular
bed Pulmonary Vascular Resistance resistance of the pulmonary
vascular bed Contractility strength of the contraction If preload,
heart rate, and afterload remain constant yet CO changes,
contractility is changed Contractility is reduced in the failing
heart
Principles of Invasive Pressure Monitoring Invasive lines used
in the ICU to measure systemic and pulmonary BPs Pressure
monitoring equipment is referenced and zero balanced to the
environment Referencing positioning transducer so the zero
reference point is at the level of the atria of the heart Stopcock
nearest transducer usually the zero reference for the transducer To
place this level with atria, need to find phlebostatic axis
Transducers placed higher than the phlebostatic axis will produce
falsely low readings Transducers placed lower than the phlebostatic
axis will produce falsely high readings Zeroing confirms that when
pressure within the system is zero, the monitor reads zero Open
reference stopcock to room air (off the patient) and watch for a
reading of zero This allows use of atmospheric pressure as a
reference for zero When to Zero? During the initial setup
Immediately after insertion of arterial line when transducer has
been disconnected from pressure cable or pressure cable has been
disconnected from monitor When the accuracy of the measurements is
questioned Types of Invasive Pressure Monitoring Arterial Blood
Pressure 20 gauge in the radial or femoral artery sutured in place
Measurement of Blood Pressure with Invasive Lines Radial, brachial,
or femoral Want to watch for infection red, swollen Should have
good wave form and be zeroed (check zero to the transducer at the
4th intercostal space) Cuff pressure should be within 10 of
arterial pressure Complications Hemorrhage use Luer-Lok
connections, check arterial waveforms, and activate alarms If
pressure in line falls (when line disconnects) an alarm will sound
Infection inspect insertion site for inflammation/infection Change
pressure tubing, flush bag, and transducer q96h When infection is
suspected, remove catheter and replace equipment Thrombus formation
To limit thrombus formation and maintain line patency, check
continuous flush system q1-4h to make sure the pressure bag is
inflated to 300 mm Hg, the flush bag contains fluid, and the system
is delivering 3-6 mL/hour Should not be using heparin routinely for
flush solution risk for thrombocytopenia Neurovascular impairment
Loss of limb
Pulmonary Artery Flow-Directed Catheter Pulmonary Artery
Catheter Insertion Note patients electrolyte, acid-base,
oxygenation, and coagulation status Imbalances such as hypokalemia,
hypomagnesemia, hypoxemia, or acidosis can make heart more
irritable & increase risk of ventricular dysrhythmia during
catheter insertion To maintain position, catheter is secured at
point of entry on skin and length marked
Pulmonary Artery Pressure Measurements PAD (pulmonary artery
diastolic pressure) & PAWP (pulmonary artery wedge pressure)
Both are sensitive indicators of cardiac function and fluid volume
status Both increase in heart failure and fluid volume overload
Both with volume depletion PAWP is pressure generated by left
ventricle (left ventricle function) Basing fluid therapy on PA
pressure can restore fluid balance w/o overcorrection or
undercorrection of the problem (can avoid pulmonary edema)
Complications with Pulmonary Artery Catheters Infection and Sepsis
Must have careful surgical asepsis for insertion and maintenance of
catheter & tubing Monitor patient for local and systemic
changes redness, exudate at insertion site, fever, increased WBC
count Must remove catheter if there are any signs of infection To
reduce risk of infection change flush bag, pressure tubing, &
stopcock q96h and remove hemodynamic monitoring once it is no
longer needed Air Embolus Always check balloon integrity before
insertion discard defective catheters After insertion, balloon
rupture or injection of air into any lumen can cause air embolus To
reduce risk of air embolus first aspirate blood to check for
absence or presence of blood and only inject prescribed volume of
air into balloon before obtaining PAWP If blood is aspirated from
balloon port or balloon air does not all come back into the
syringe, label port do not use and contact physician Always use
Luer-Loks on all pressure lines and activate low pressure alarms
Pulmonary Infarction or PA Rupture Causes Balloon may rupture,
releasing air and fragments that could embolize Prolonged balloon
inflation may obstruct blood flow Catheter may advance into a wedge
position, obstructing blood flow Thrombus could form and embolize
To reduce risk of air embolus/pulmonary infarction never inflate
balloon beyond capacity (1-1.5 mL of air), monitor PA pressure
waveforms continuously for evidence of catheter occlusion,
dislocation, or spontaneous wedging Pressure tracing will be
blunted with occlusion and will appear wedged if PA catheter
advances and becomes wedged Physician must reposition catheter
immediately ALWAYS CLOSE LINE WITH CLAMP OR STOPCOCK WHEN LINE IS
DISCONNECTED NEVER LEAVE BALLOON INFLATED FOR MORE THAN 4 BREATHS
(8-15 SECONDS) EXCEPT DURING INSERTION To reduce risk of
thrombus/embolus formation PA catheter needs to be continuously
flushed with a slow infusion of normal saline Ventricular
Dysrhythmias Can occur during PA catheter insertion or removal or
if tip moves from PA to R ventricle and irritates ventricular wall
(PA catheter would not be able to be wedged) Needs to be
repositioned by physician and chest x-ray done to confirm location
Central Venous or Right Atrial Pressure Measurement (CVP)
Measurement of right ventricular preload Measured with PA catheter
using the proximal lumen located in the right atrium or with a
central venous catheter placed in the internal jugular or
subclavian vein Also reflects fluid volume problems, but PA
diastolic pressure & PAWP are better indicators of it Increase
in CVP reflects heart failure or volume overload WANT TO CVP TO
CARDIAC OUPUT!!! Decrease in CVP reflects volume depletion CVP
Waveform Interpretation a wave represents atrial contraction x
descent represents atrial relaxation c wave represents the bulging
of the closed tricuspid valve into the right atrium during
ventricular systole v wave represents atrial filling y descent
represents opening of the tricuspid valve and filling of the
ventricle
Invasive Cardiac Output Measurement Techniques Normal resting
cardiac output is 4-8L per minute CO & CI are in shock states
(e.g. cardiogenic, hypovolemic) and heart failure CO with exercise
and at rest with fever or early sepsis TDCO (intermittent bolus
thermodilution CO) CO is calculated from temperature change in
pulmonary artery when a fixed volume and known temperature of a
solution is injected into proximal port in right atrium CO measured
by computer from area under the temp curve Want curve to be smooth
Larger area under curve = lower CO Smaller area under curve =
higher CO Repeat 3x with each measurement 1-2 minutes apart to
determine CO Must have three normal curves to be valid throw out
any abnormal curves CCO (continuous cardiac output method) CO
measured with a PA catheter (placed in the right atrium) that has a
heat-exchange CO catheter attached to detect changes in temp when
blood passes through R ventricle Every 30-60 seconds, a bedside
computer displays average CO for the past 3-6 minutes Eliminates
need for fluid boluses, decreases contamination, permits ongoing
evaluation MORE RELIABLE THAN TDCO METHOD Minimally Invasive
Cardiac Output Monitoring Techniques Use of a specialized sensor
that attaches to a standard arterial pressure line and a monitor
Measures CCO/CCI, SV/SVI, and stroke volume variation q20secs More
research needed to find if this approach can replace hemodynamic
monitoring with PA catheter Venous Oxygen Saturation Both CVP
(central venous pressure) and PA (pulmonary artery) catheters can
include sensors to measure O2 saturation of hemoglobin in venous
blood O2 saturation of blood from PA catheter = mixed venous oxygen
saturation (SvO) O2 saturation of blood from CVP catheter = central
venous oxygen saturation (ScvO) Both are adequate for the
measurement of adequate tissue oxygenation Normal SvO/ScvO at rest
is 60-80% SvO/ScvO arterial oxygenation, low CO, low hemoglobin,
consumption or extraction of O If below 60%, observe for changes in
arterial oxygenation Monitor pulse oximetry or ABGs Indirectly
assess CO and tissue perfusion changes in mental status, strength
or quality of peripheral pulses, capillary refill, urine output,
skin color & temp If arterial oxygenation, CO, and hemoglobin
are unchanged, the in SvO/ScvO is from O consumption or extraction
could be metabolic rate, pain, movement, or fever SvO/ScvO Could be
from an improvement (e.g. O saturation, improved perfusion,
metabolic rate) or from a problem (e.g. sepsis) In sepsis there is
a ability of tissues to use O at the cellular level
Noninvasive Hemodynamic Monitoring Impedance Cardiography (ICG)
Method of obtaining CO and assessing thoracic fluid status
continuous or intermittent Uses four external electrodes that
deliver a high frequency, low amplitude current to measure the
change in impedance in the ascending aorta and left ventricle over
time Impedance the resistance to the flow of electric current
Cannot use in patients with generalized edema or third spacing
excess volume interferes with accuracy Noninvasive Arterial
Oxygenation Monitoring Pulse Oximetry Monitoring SpO may reduce
frequency of ABG sampling SpO is normally 95%-100% Can put pulse ox
probe on forehead, earlobe, etc. if cannot get good reading on
fingers Normally used to evaluate effectiveness of oxygen therapy
and how patient tolerates position changes or decreases in fraction
of inspired air (FIO) Nursing Management of a Patient on
Hemodynamic Monitoring Obtain Baseline Data General appearance Does
the patient appear tired, weak, exhausted? Level of consciousness
Cardiac reserve may be insufficient to sustain even minimum
activity Changes in mental clarity may reflect problems with
cerebral perfusion or oxygenation Skin color/temperature Pallor,
cool skin, and diminished pulses may indicate decreased CO If
patient is bleeding and developing shock, BP might initially be
stable, yet patient may become increasingly pale and cool from
peripheral vasoconstriction Conversely, patient with septic shock
may remain warm/pink yet develops tachycardia and BP instability
Vital signs Peripheral pulses Capillary Refill Urine output
Monitoring urine output reflects the adequacy of perfusion to the
kidneys Patient with diminished perfusion to GI tract may have
hypoactive or absent bowel sounds Correlate baseline data with data
obtained from biotechnology e.g., ECG; arterial, CVP, PA, and PAWP
pressures; SvO2/ScvO2 Single hemodynamic values are rarely
significant Monitor the whole clinical picture
Circulatory Assist Devices (CADs) Used to decrease cardiac work
& improve organ perfusion in patients with heart failure when
drugs are no longer adequate All CADs decrease ventricular
workload, increase myocardial perfusion, and augment circulation
Provide Interim Support in Three Types of Situations Left, right,
or both ventricles require support while recovering from acute
injury (e.g., postcardiotomy) Patient must be stabilized before
surgical repair of the heart (e.g., a ruptured septum) Heart has
failed, and the patient is awaiting cardiac transplantation
Intraaortic Balloon Pump (IABP) most commonly used CAD Provides
temporary circulatory assistance (improving coronary blood flow) to
compromised heart by Reducing afterload (reducing systolic
pressure) Enhancing the aortic diastolic pressure
Balloon inserted percutaneously or surgically into the femoral
artery, advanced toward the heart, and positioned in the descending
thoracic aorta just below the left subclavian artery and above the
renal arteries During systole balloon is deflated (on R wave),
which facilitates ejection of the blood into the periphery In early
diastole, balloon begins to inflate (on T wave) In late diastole,
balloon is totally inflated Increases aortic pressure and increases
coronary perfusion pressure with the end result of increased
coronary and cerebral blood flow X-ray is used to verify location
after placement IABP therapy is called Counterpulsation balloon
inflation is opposite to ventricular contraction 1:1 ratio in acute
phase of treatment one IABP cycle of inflation and deflation for
every heartbeat
Complications with IABP Therapy Signs of a leak include Less
effective augmentation Repeated alarms for gas loss Blood backing
up into the catheter Patient is relatively immobile, limited to
side-lying or supine positions with HOB