ACUTE RESPIRATORY DISTRESS (ARDs)

Lecture Notes February 26, 2001

Exam #3


Review Nursing Care Plan Page:  1902-1903 and 1949 – 1951

 

ARDs syndrome

N      Sudden progressive pulmonary disorder

1.      Acute lung inflammation

2.      diffuse alveola capillary injuries characterized as severe dyspnea, hypoic PaCo2 <50 or 60

 

N      Mortality rate is high

N      Young adults   40% die

N      Elderly  60%  die

 

Cause of ARDs:

 

N      Insult – bacterial infection (i.e., pneumonia, septicemia)

N      Medical conditions; trauma cases, burns, shock

N      Noxious events; exposure to smoke

 

Leads to ARDs directly:

 

N      Viral, bacterial, fungal pneumonia

N      Lung contusion

N      Fat embolus

N      Aspiration (forign material, drawning)

N      Massive smoke inhalation

N      Inhaled toxic

N      Prolonged exposure to high concentration of oxygen

 

Direct pulmonary Trauma:

 

N      Sepsis

N      Shock

N      Multisystem trauma

N      DIC

 

Early Signs & Symptoms of ARDs:

 

N      Rapid shallow breathing

N      Air hunger

N      Cyanosis (nail membranes)

N      Respiratory alkalosis FIRST

N      Marked dyspnea

N      Hypoxemia Pa02 <60 mm Hg when on 60% oxygen, lung sounds clear to fine crackles

 

Late Signs & Symptoms of ARDs:

 

N      Decreased lung compliance

N      Defuse bilateral infiltrates …… Xray

N      Metabolic acidosis or Respiratory acidosis

 

Diagnosis by respiratory assessment of lung sounds

ABG’s need to be evaluated

Chest X-ray

 

Treatment/Goals:

 

  1. Respiratory support
  2. Treat cause
  3. Prevent complications

 

Mechanical ventilation:

 

    1. Intubate:

                                                               i.      Endotracheal tube, (can get sores in mouth, can use for 10 to 14 days only)

                                                             ii.      Tracheostomy Tube, (neet a tube of the same size taped to HOB and trach dilator.

    1. Goals:

                                                               i.      Adequate ventilation

                                                             ii.      Precise concentration of F;oxygen RA=21%

                                                            iii.      Adequate title volume

                                                           iv.      Decrease work of breathing

 

Shiley Trach:  disposible inner canula

Fenestrated trach:  used for long term & pt can talk

 

If on a ventilator you should give ativan push to help with anxiety.

 

Treatment:

 

N      Mechanical ventilation with PEEP

N      Sedation

N      Neuromuscular blocking agents

§         Pavulon (paralyzed patient)

§         Vecuronium

§         Atracurium

 

Other treatments for ARDS:

 

N      Treat cause

N      Shock:  HTN or Cardiac

§         Increased cardiac output and increased BP, multiple lines

§         Dopamine and dobutamine for increased BP (SBP <100)

 

N      Infections: 

§         Sputum specimen with suction

§         Treat with antibiotics until culture returns (broad spectrum Abx)

§         May use antiinflammatories (i.e., methylprednisone)

 

N      Monitor for complications: (Cardiac dysrhythmias)

§         Due to hypoxemia

§         Renal failure

§         Thrombocytopenia with infection process

§         Sepsis

§         DIC

§         Stress ulcers

§         May develop mult. Lines

§         Arterial, swan for cardiac output

 

N      Complications of positive pressure ventilation

§         Decreased cardiac output

§         Decreased blood flow to splanchnic area (3rd spacing, high pressure)

·        Ischemic gastric mucosa (cause of stress ulcer, pepsid, zantac, histamine blackers)

·        Decreased renal blood flow d/t decreased CO, will increase peripheral edema, decrease urine output and fluid retention (diuretics:  Lasix or Bumex)

·        Respiratory alkalosis:  Title volume delivered is too high, Respiration rate is too high.  May lead to seizure or alkalosis development.

 

N      Reasons for Mechanical Ventilation

1.      Permanent d/t quads, Lou Gehrig’s Disease, MS, neuromuscular conditions.

2.      Correct hyopoxemia

 

N      Three types of Positive Pressure Ventilators:

1.      Volume Cycled ventilator:  used in acute problems (ie, spinal cord injury or COPD.  Inspiration occurs until a preset volume of air is delivered.

2.      Pressure Cycled Ventilator:  Used in home with long term patients.  Inspiration ends when preset pressure is reached.  20 – 50 cm of water pressure.

3.      Time Cycled Ventilator:  How many breaths/minute used with kids and infants.  Inspiration ends with a preset time of enterval.

 

N      Mods of Ventilation:

1.      Control mode – CMV needed with neuroblocking agent.  Ventilator does all the work.

2.      Assist/Control – Machine assist patient.  Patient triggers and then machine takes over.

3.      Intermittent Mandatory Ventilator (IMV) – Trying to ween off ventilator.  Machine lets patient breath on own.

4.      Synchronized Intermittent mandatory Ventilator (SIMV) – The machine breaths are synchronized with the patients breaths.

5.      Pressure Support Ventilator (PSV) – Used for weening when close to coming of ventilator.  Patient breaths spontaneously.  NOTE:  LOOKING @ PRESET PRESSURE

6.      Positive End Expiratory Pressure (PEEP) – preset amount of pressure left in the lungs @ the end of exhale to keep aveola open.  Like a balloon not totally deflated.  Oxygen defuses easier into capillaries.  It’s a positive pressure 5-20cc/water a setting on ventilator.

7.      C-PAP – Similar to PEEP, a continuous positive airway pressure.