Week 11: Burns & Respiratory Distress Flashcards
Burns
Occur when injury to the tissues of the body is caused by:
-Heat
-Chemicals
-Electric current
-Radiation
Types of Burn Injury (Thermal Burns)
-caused by flame, flash, or contact with hot objects
-the most common type of burn injury
Types of Burn Injury (Chemical Burns)
-results from tissue injury and destruction from acids, alkalis, and organic compounds
Types of Burn Injury (Smoke Inhalation Injury)
-results from inhalation of hot air or noxious chemicals (i.e CO poisoning)
-cause damage to the tissues respiratory tract
-responsible for up to 77% of deaths, largely related to carbon monoxide poisoning
Types of Burn Injury (Electrical Burns)
-caused by intense heat generated from an electric current
-May result in direct damage to nerves and vessels, causing tissue anoxia and death
-severity depends on the amount of voltage, current pathways, surface area in contact with the current, and length of time that the current flow was sustained
-Can be difficult to determine since most of the damage is below the skin
Classification of Burn Injury
SEVERITY is determined by:
-Depth of burn
-Extent of burn
-Location of burn
-Client risk factors
GOALS of care:
-wound healing
-prevention of infection
-pain management
-return to preinjury function
Classification: Depth
Burns are defined by degrees
1st DEGREE- superficial partial thickness burn
-involves the epidermis (sunburn)
2nd DEGREE- deep partial-thickness burn
-Involves the dermis
3rd&4th DEGREE- full thickness burn
-involves fat, muscle, bone
-significant damage to the dermis-remaining skin cells are insufficient to regenerate new skin
Classification: Extent
Lund–Browder Chart:
-Considered more accurate
-Considers the client’s age, in proportion to relative body-area size, is taken into account
The Rule of Nines:
-Easier to remember
-Considered adequate for initial assessment of an adult burn client
-Commonly used in emergency
*extent of a burn is often revised after edema has subsided
Classification: Location
Location of burn related to the severity of the injury
-Face, neck, chest → respiratory obstruction
-Hands, feet, joints, eyes → self-care
-Ears, nose, buttocks, perineum → infection
Circumferential burns of the extremities can cause circulatory compromise
Potential for compartment syndrome from direct heat damage to the muscles and subsequent edema and/or pre-burn vascular problems
Patient Risk Factors
-Older adults heal more slowly than younger adults
-Pre-existing cardiovascular, respiratory, & renal diseases contribute to poorer prognosis
-Diabetes or peripheral vascular disease contributes to poor healing
-Concurrent fractures, head injuries, or other trauma also lead to poor prognosis
-Physical debilitation renders client less able to recover:
a.)alcoholism/drug abuse
b.)malnutrition
Phases of Burn Management (Pre-Hospital Care)
-At the injury scene, priority is to remove the person from the source of the burn and stopping the burning process
Phases of Burn Management (Emergent)
RESUSCITATIVE
-The period of time required to resolve the immediate, life- threatening problems resulting from the burn injury
-Lasts up to 72 h
Phases of Burn Management (Acute)
WOUND HEALING
-Begins with mobilization of extracellular fluid & subsequent diuresis, and concludes when the burned area is completely covered by skin grafts or when the wounds are healed
-This may take weeks or many months
-Longest stage
Phases of Burn Management (Rehabilitative)
RESTORATIVE
-Begins when the patient’s burn wounds have healed and the patient is able to resume a level of self-care activity
Emergent Phase (Resuscitative)
Greatest threat is hypovolemic shock & subsequent edema
-caused by a massive shift of fluids out of the blood vessels due to ↑ capillary permeability
Toward the end of the phase:
-capillary membrane permeability is restored
-fluid loss & edema formation cease
-interstitial fluid gradually returns to the vascular space
Capillary Permeability- Hypovolemia
-Inflammation
-↑ capillary permeability
-Massive shift of H2O, Na+, albumin
-Interstitial space (second spacing)
-↓ osmotic pressure
-↑ fluid shifting (third spacing)
-Intravascular volume depletion
-Hypovolemia
Emergent Phase- Clinical Manifestations
Pain
-Areas of full-thickness & deep partial-thickness burns are initially anaesthetic because the nerve endings are destroyed
-Superficial to moderate partial-thickness burns are extremely painful
Most Patients are Alert & Often Frightened
-benefit from calm reassurance & simple explanations by health care providers
-If inhalation injury has occurred-the upper airway is vulnerable to edema formation and airway obstruction
Emergent Phase Inflammation & Healing
-Neutrophils and monocytes accumulate at the site of injury
-Fibroblasts & collagen fibrils begin wound repair within the first 6–12h
Immunological Changes:
-widespread impairment of the immune system
-Skin barrier is destroyed
-Bone marrow is depressed
-Circulating levels of immune globulins are decreased
-WBC’s defects
Emergent Phase (Cardiovascular System)
-Dysrhythmias & hypovolemic shock
-Impaired circulation to extremities
-Tissue ischemia
-Necrosis: escharotomy
Emergent Phase: Respiratory Phase
-URT injury: inhalation of hot air, steam, smoke
-Edema formation: mechanical airway obstruction & asphyxia
-LRT injury: inhalation of toxic chemicals or smoke
-Pulmonary edema
Lower respiratory tract injury is concerned with impaired gas exchange
Emergent Phase (Urinary System)
-Acute tubular necrosis (ATN)
-Hypovolemia: decreased kidney blood flow: renal ischemia: AKI
-Full-thickness & electrical burns: myoglobin & hemoglobin are released into the bloodstream: occlude the renal tubules
-Decreased blood flow to kidneys causes renal ischemia
Emergent Phase: Collab & Nursing Care
(airway management)
PRIORITY:
airway management, fluid therapy, wound care
Frequently requires endotracheal (ET) intubation:
-extubation may be indicated when the edema resolves, usually 3 to 6 days after burn injury
Respiratory Distress
-r/t circumferential burns to neck & truck (escharotomy)
Bronchoscopy
-To assess lower airway
CO poisoning
-100% O2
Emergent Phase: Collab & Nursing Care
(Fluid Therapy)
-Critical for fluid resuscitation & meds
-Establish IV access to accommodate large volumes of fluid
-Type of fluid determined by size/depth of burn, pt’s age, & pre-existing conditions
a.) lactated ringers, colloids, combo (isotonic soltn)
Adequacy of fluid replacement
-Urine output – 0.5-1 ml/kg/h
-Cardiac factors
-Mean arterial pressure > 65 mmHg
-Systolic BP >90 mmHg
-HR < 120 bpm
Emergent Phase: Collab & Nursing Care
(Wound Care)
-Full-thickness burn wounds are dry and waxy white to dark brown or black
-have minor, localized sensation because nerve endings have largely been destroyed
-Partial-thickness burn wounds appear pink to cherry red and are wet and shiny with serous exudate
-Cleansing & gentle debridement to prevent infection
-Necrotic skin removed
-Coverage is the primary goal
-Moist wound healing and use dressings to cover
-Moisture allows the movement of cells to start knitting together
Emergent Phase: Collab & Nursing Care
-The face is highly vascular and subject to a great amount of edema
-Arterial blood gases (ABGs) are measured to determine adequacy of ventilation & perfusion with inhalation or electrical injury
-Physiotherapy is begun immediately to facilitate mobilization of the extravasated fluid back into the vascular bed
-Maintains function, prevents contracture
-Opioids are the drugs of choice for pain control
-Analgesic requirements can vary tremendously from one patient to another
-The extent and depth of burn may not be correlated with pain intensity
-Lower extremity burns: risk for venous thromboembolism (VTE)
-Low-molecular-weight heparin as prophylaxis
Emergent Phase: Nutrition Therapy
Huge caloric needs – metabolism may ↑ 50-100%!
-Inadequate calories & protein: malnutrition & delayed healing
Early & aggressive nutritional support can:
-decrease mortality risks & complications
-optimize healing of the burn wound, and
-minimize the negative effects of hypermetabolism & catabolism
Enteral Feedings
Acute Phase (Wound Healing)
-Diuresis from fluid mobilization occurs, and the client is less edematous
-Bowel sounds return
-Healing begins when:
a.) WBCs surround the burn wound, phagocytosis occurs
b.) Necrotic tissue begins to slough
c.) Granulation tissue forms
-Full-thickness burns must be covered by skin grafts
Acute Phase: Collab & Nursing Care
The predominant therapeutic interventions in the acute phase are:
-Wound care
-Excision & grafting
-Pain management
-Physiotherapy & occupational therapy
-Nutritional therapy
-Psychosocial care
Acute Phase: Collab & Nursing Care
GOALS
-prevent infection
-promote wound reepithelialization / skin grafting
EXCISION
GRAFTING
Excision
-Eschar is removed down to the subcutaneous layer
Acute Phase Nursing Care (Pain Management)
-Individualized & ongoing pain assessment & mgmt
-One of the most critical functions a nurse performs on behalf of a patient with burn injuries
Acute Phase Nursing Care
(Physical & occupational therapy)
-To maintain muscle strength & optimal joint function
Acute Phase Nursing Care (Nutritional Therapy)
-provide adequate calories & protein to promote healing
Acute Phase Nursing Care (Psychosocial Care)
-support during the often lengthy, unpredictable, & complex course of care
-SW & nursing play an important role
Rehabilitation Phase (Restorative)
GOALS:
-assist the patient in resuming a functional role in society
-rehabilitation after functional and cosmetic reconstructive surgery
MANIFESTATIONS:
-new skin appearing flat & pink
-then raised and hyperemic
-itching occurs with healing
Complications are skin & joint contractures and hypertrophic scarring:
-mgmt includes positioning, splinting, and exercise to minimize this
Rehabilitation Phase- Nursing Care
-Patient teaching using return demonstration (show-back) for dressing changes & ongoing wound care is essential to ensure good post-discharge wound healing
-Continuous exercise and physical & occupational therapy cannot be overemphasized
-Encouragement & reassurance are necessary for patient morale, attaining independence, and returning to pre-burn activities
Alveolus: Gas Exchange
-Only the alveoli function in the exchange of the respiratory gases between the outside air and the blood
Respiratory Failure
Respiratory failure is the state in which one or both gas-exchanging functions are inadequate
-Either the amount of O2 transferred to the blood is insufficient
-the amount of CO2 removed from the lungs is inadequate
Respiratory Failure
-With inadequate gas exchange, the metabolic demands of the tissues are not met, and body systems begin to rapidly fail
Hypoxemia: low O2 in blood
-↓ partial pressure of O2 (PaO2 <60 mmHg)
-↓ arterial O2 sats (SaO2)
Hypercapnia: high CO2 in blood
-↑ partial pressure of CO2 (PaCO2)
Respiratory Failure
-Though respiratory failure is determined by the PaO2 & PaCO2, the major threat is the inability of the lungs to meet the oxygen demands of the tissues
-May develop suddenly or over several days
-Important to monitor trends in ABGs & SaO2
Initial Symptoms
-Change in pt’s mental status
-cerebral cortex is very sensitive to changes in oxygenation & acid-base balance
-Tachycardia & mild hypertension
-Heart Tries To Compensate
Diagnostics
ABGS necessary to determine:
-oxygenation (PaO2) & ventilation (PaCO2) status
-acid–base balance
Chest X-Ray
Pulse oximetry (SaO2)
Pulmonary Artery Catheter to Measure Pressures:
-on the right side of the heart and cardiac output
-mixed venous oxygen saturation
Acid Base Imbalance: Respiratory
Acidosis: (hypoventilation)
Increased CO2 in blood & increased carbonic acid
-COPD
-Overdose
-Severe pneumonia
Alkalosis: (hyperventilation)
Decreased CO2 in blood / decreased carbonic acid
-Hypoxia, PE
-Anxiety, fear, pain
-Septicemia, encephalitis
Arterial Blood Gases- ABGs
PaO2: partial pressure of oxygen
(75-100 mmHg)
-Measures O2 pressure in blood
-Reflects how well O2 is able to move from lungs to blood
PaCO2: partial pressure of carbon dioxide
(35-45 mmHg)
-Measure CO2 pressure in blood
-Reflects how well CO2 is able to move out of the body
HCO3: bicarbonate (22-26 meq/L)
-Chemical buffer that keeps the blood pH stable
pH (7.4)
-Measures hydrogen ions (H+) in blood
Oxygen
-The fraction of inspired oxygen (FiO2) is the concentration of oxygen in the gas mixture
-The gas mixture at room air has a FiO2 of 21%, meaning that the concentration of oxygen at room air is 21%
(But, this is not the amt that participates in O2 gas exchange at the alveolar level)
-For every litre of O2 flow, the FiO2 increases by 4%
Oxygenation
-The primary goal of O2 therapy is to correct hypoxemia
-O2 delivery: nasal cannula, face mask, Venturi mask
Maintain PaO2 at 55-60 mmHg
Maintain SaO2 at 90%
* At lowest O2 concentration possible
High O2 concentration** : adverse effects
Intubated patients who receive >50% FiO2 for >24h are at risk to develop O2 toxicity
Artificial Airways
Endotracheal Intubation (ET)
-via mouth or tracheotomy
Indications for Use
-Upper airway obstruction
-Secondary to burns, tumour, bleeding
-Apnea
-Respiratory distress
-Inability to maintain the airway
-ineffective clearance of secretions, altered or decreased level of consciousness
Artificial Airways- Nursing Management
-Maintaining correct tube placement
-Maintaining proper cuff inflation
-Monitoring oxygenation & ventilation
-Maintaining tube patency
-Assessing for complications
-Providing oral care & maintaining skin integrity, and
-Fostering comfort and communication
Mechanical Ventilation
-The process by which ventilation and oxygenation is supported or conducted by a machine
Indications for Use
-Apnea or impending inability to
-Acute respiratory failure
-Severe hypoxia, and,
-Respiratory muscle fatigue
Mechanical Ventilation: Types
Negative Pressure Ventilation
Positive Pressure Ventilation (PPV)
Non-Invasive (NPPV)
- Continuous positive airway pressure (CPAP)
-Bilevel positive airway pressure (BiPAP)
Invasive
-Spontaneous mode
-Control mode
Non-Invasive (NPPV): CPAP
-One pressure setting that is set
-Keeps the airways & alveoli open during inspiration & expiration and prevents collapse
Non-Invasive (NPPV): BiPAP
-Two pressure settings
Inspiratory (I-PAP): PCO2 levels
-Improves ventilation
Expiratory (E-PAP): PO2 levels
-Improves oxygenation
Invasive (PPV)- Modes
-Respiratory therapists assume a key role in determining optimal ventilator settings
SPONTANEOUS
-The patient is able to determine the respiratory rate and the ventilator assists the patient
CONTROL
-The number of breaths, the size of the breaths, and the pressure generated are all controlled and preset
Positive End-Expiratory Pressure (PEEP)
-a ventilatory setting in which positive pressure is applied to the airway during exhalation
-the major purpose of PEEP is to maintain or improve oxygenation while limiting risk for O2 toxicity
-the equivalent of E-PAP in non-invasive (NPPV)
Acute Respiratory Distress Syndrome (ARDS)
-Sudden & progressive form of acute respiratory failure in which the alveolar-capillary membrane becomes damaged and more permeable by intravascular fluid
The alveoli fill with fluid, resulting in:
-severe dyspnea
-hypoxemia refractory to supplemental O2
-reduced lung compliance
-diffuse pulmonary infiltrates
Despite supportive therapy, the rate of mortality from ARDS is approximately 50%
ARDS- Progression
Injury or Exudative Phase
-occurs 24-48 h
-interstitial and alveolar edema
Reparative or Proliferative Phase
-Begins 1-2 weeks later
-Lung is defined by dense, fibrous tissue
Fibrotic Phase
-Occurs 1 week after previous phase
-Lung is completely remodelled with diffuse scarring and fibrosis
-PROGNOSIS IS POOR at this stage
ARDS PROGRESSION
-As ARDS progresses, it is associated with profound respiratory distress that necessitates endotracheal intubation and PPV
-Severe hypoxemia, hypercapnia, & metabolic acidosis, with symptoms of target organ or tissue hypoxia, may ensue if without prompt treatment
-The major cause of death in ARDS is MODS, often accompanied by sepsis
ARDS Nursing Care
GOAL
PaO2 of at least 60 mmHg & adequate lung ventilation to maintain normal pH
CORRECT THE HYPOXEMIA
-Pts commonly need intubation with mechanical ventilation because the PaO2 cannot otherwise be maintained at acceptable levels
Positive End-Expiratory Pressure (PEEP)
-It is a ventilator setting
-Keeps alveoli open to maximize O2 exchange
Prone Position
-Demonstrated improvement in PaO2
-Changes the dynamic of ventilation
