Respiratory 2

Question 1

PaCO2 greater than 45

Answer 1

respiratory acidosis

Hypoventilation (can be due to medications that depress the resp. center)

Pulmonary disease (COPD, pneumonia, pulmonary edema)
CNS disturbances that damage the respiratory center in the medulla

Question 2

PaCO2 less than 35

Answer 2

respiratory alkalosis

Hyperventilation (can be due to anxiety)

Hyperthyroidism

Question 3

HCO3 less than 22

Answer 3

metabolic acidosis

DM, sepsis, starvation, anaerobic metabolism, chronic diarrhea

Question 4

HCO3 more than 26

Answer 4

metabolic alkalosis

Vomiting, gastric suction, hypokalemia, antacid abuse

Question 5

Indications for Mechanical Ventilation

Answer 5

Apnea: post cardiac arrest, alcohol intoxication, medications

Acute Respiratory Failure

Impending Respiratory Failure

Anesthesia-induced hypoventilation

Severe Oxygenation Deficit

Question 6

Non respiratory indications for mechanical ventilation

Answer 6

Treatment for other disease processes may cause respiratory depression:

• Chemically-induced coma for raised ICP
  or cerebral edema.
• Surgical healing may require patient to be very still—major abdominal surgery, skin flaps. Patient may be sedated and chemically paralyzed with cisatracurium (Nimbex), others…Atracurium or Vecuronium, for
  1-2 days to allow healing of delicate anastomoses.

Risk of airway occlusion from edema—major oral surgery—need for nasal intubation until edema resolves.

Management of severe aggression—trauma resus.
Patients often drug-impaired. May require immediate sedation and intubation to facilitate treatment.

Question 7

Clinical Objectives

Answer 7

To reverse hypoxemia

To reverse acute respiratory failure

To relieve respiratory distress

To permit sedation and /or neuromuscular block

To decrease systemic or myocardial O2 consumption (decreases work of breathing)

To maintain or improve cardiac output

To reduce intracranial pressure (keep PCo2 around 35 mmHg)

To stabilize the chest (post-cardiac surgery, or traumatic injury)

Question 8

Ventilator Settings Three Important Settings

Answer 8

1. Tidal Volume which is the amount of air pumped into the lungs with each stroke. If we breathe normally, tidal volume is what we normally inhale (approx 5-10mls/kg)
2. FiO2 is the percentage of air that is oxygen that the ventilator delivers. Atmospheric air is 21% O2. A ventilator can change the percentage to a more concentrated dose (ie. 50% or 100%)
3. Respiratory Rate (RR) is the rate of breaths set by the RT 10-14 range

Question 9

Types of Mechanical Ventilators

Answer 9

Volume Cycled - Delivers a pre-determined MINUTE VOLUME as ordered by the MD/NP (Minute volume = breaths x tidal volume) This is the most common ventilator we utilize in the acute care setting.

Pressure Cycled or Pressure Control Ventilation- Delivers a set pressure (mostly used with children and infants but now commonly used for adults with decreased lung compliance-ARDS).

External Body Ventilators (Iron Lung) - Assist in spontaneous ventilatory effort by applying negative pressure to the trunk of the body (VERY rarely used today but still available)

Question 10

Controlled Mandatory Ventilation

Answer 10

The ventilator does ALL the work. The patient is unable to take a spontaneous breath. Useful if the patient is apneic due to chemical paralysis. Allows patient to rest.

Question 11

Assist Control Mode

Answer 11

Most patients are placed on this mode initially. It means that the machine gives the patient the number of breaths ordered (i.e., AC 12 per minute) at the tidal volume that is ordered and set on the machine (ie 450 ml TV). The ventilator will deliver 12 breaths , each breath 450 ml.

In between those 12 machine breaths, the patient can initiate extra breaths. If he patient inhales just the tiniest bit, the machine will deliver a full (ie. 450 ml) breath at the preset volume.

****Note In the AC mode, the machine does all the work. If the patient wants more air, the machine will give it with no extra work except attempting to take a breath.

Question 12

SIMV Mode

Synchronized Intermittent Mandatory Ventilation (SIMV)

Answer 12

When a patient is starting to initiate their own breaths, the MD may wish to start “weaning” the patient from the ventilator. To start the weaning process, we encourage the client to “breathe more frequently on their own” while still having the support of the ventilator if they fail.

***Increased PEEP causes a drop in blood pressure

Question 13

Pressure Support Ventilation

Answer 13

Often used with SIMV and CPAP

Augments a spontaneously generated breath since it adds pressure to the air the patient is inhaling.

The patient’s inspiratory effort is assisted by the ventilator at a preset inspiratory pressure (not volume).

Helps overcome “dead space.” Tubing leading to ventilator plays no part in gas exchange but patient has to expend more energy when breathing because of length of tubing. Pressure support “blows air” at the patient and makes it easier to take a breath in.

Question 14

Pressure Control (PC)

Answer 14

Used for ARDS to avoid barotrauma and deliver smaller volumes of Vt or used for inverse I:E

Question 15

PEEP

Answer 15

PEEP (Positive End Expiratory Pressure) is a constant small pressure that keeps the alveoli slightly inflated. PEEP prevents the alveoli from collapsing at the end of the breathing cycle. By keeping the alveoli inflated, oxygen pressure is maintained and oxygenation of the blood improved.

The pressure gauge on the ventilator will tell you if the PEEP is set since the pressure in between breaths does not return to “0”(atmospheric pressure) but is set (ie. at 5,10 or 15 cm.)

Question 16

CPAP

Answer 16

Continuous Positive Airway Pressure, or Pressure Support Ventilation

*****Patient MUST be breathing SPONTANEOUSLY!

Continuous pressure with or without O2 is delivered to the patient in order to assist respiration, prevent/reverse alveolar collapse

**Can be used as a mode of ventilation when an intubated patient is breathing spontaneously and is being weaned. NO SET RATE. Be off sedation/very minimal to breathe

Can also be used with a tight-fitting face mask in an effort to prevent intubation in a patient with respiratory compromise. This can be VERY uncomfortable and difficult for the patient to tolerate.

Question 17

CPAP Continued

Answer 17

Full face CPAP mask very tight—patient may not tolerate. Precedex drip often used—mild sedation without respiratory depression.
Need Q2h mouthcare and eyecare.
Nasal CPAP used for patients with sleep apnea—usually obese but not always.

Question 18

If the ventilator is alarming and you don’t know why….

Answer 18

Ambubag with 100% O2 and call for HELP!

Question 19

Ventilator Alarms Causes

Answer 19

Causes (most common):

Patient is biting on the ETT (insert bite block if necessary)

Patient is agitated and fighting the ventilator

Patient is coughing

Secretions or mucus in the airway

Water in the tubing or tubing kinked

Pneumothorax
Pulmonary compliance issues (developing ARDS)
Stiffening of the lungs R/T scarring or ischemia
Air trapping and reduced alveolar space-alveolar collapse.

Question 20

Ventilator Alarms (Low Pressure) Causes

Answer 20

Causes:

Patient is disconnected, Circuit leaks, Airway leaks (ET tube dislodged or balloon deflated), Chest tube leaks

Question 21

High Inspiratory Rate

Answer 21

The patient is breathing quite rapidly. Pain or agitation might be a reason. If the patient was breathing rapidly on SIMV, it might mean they need to be changed to Assist Control. That way they would expend less energy.

Question 22

Low Minute Volume Alarm

Answer 22

Low Minute Volume Alarm - means the ventilator could not deliver the preset volume.
Check for tubing disconnection—most common cause.

Question 23

Nursing Management Vent Alarms

Answer 23

Suction ETT prn. Auscultate breath sounds. Pre-oxygenate with 100% FiO2. All vents have a button that will allow you to place pt on 100% for 1-3 minutes. Suction for NO MORE than 15 seconds. Apply suction upon withdrawel of catheter.

Use closed suction system, such as Ballard.
Do not use saline lavage routinely!

*** “Routine” suctioning is not good practice-can cause traumatic injury to lungs and distress to the patient.

Question 24

VAP Protocol

Answer 24

Keep HOB up 30 degrees if not contraindicated.
Reposition every 2 hours (aids pulmonary drainage of secretions)

Mouth care AT LEAST every 4 hours, preferably every 2 hours. Bacteria migrate downwards from the oropharynx.

Wrist restraints per hospital policy—LEAST restrictive measures always—BIG with JCAHO!

Alarms on (ventilator and monitor), appropriate parameters set, and AUDIBLE!

Ambubag at bedside and easily accessible. Keep it attached to the O2 so you can turn it on quickly in an emergency.

Question 25

Monitor for complications (Vent Alarms)

Answer 25

Respiratory:
Barotrauma
Volutrauma
Ventilator Associated Pneumonia (VAP)

Musculoskeletal
Immobility
Myopathies, neuropathies from long-term sedation

CV:
Hypotension, ↓CO
Sodium & water imbalance

GI:
Stress ulcers, constipation, ileus
Machine disconnection or malfunction

Question 26

ARDS Effects

Answer 26

Impaired oxygenation
Pulmonary vasoconstriction
Pulmonary hypertension (can lead to RV failure)
Reduced blood flow
Impaired ventilation
Decreased lung compliance and increased airway resistance
Fluid-filled alveoli (pulmonary edema)
Alveolar collapse
Bronchoconstriction

Question 27

Oxygenation and Ventilation

Answer 27

Refractory hypoxemia hallmark of ARDS
Goal to optimize oxygen delivery
Fluid management (challenging—need to control pulmonary edema without dehydrating patient)
Positive inotropic agents and vasoconstrictors
May need ECMO (extra corporeal membrane oxygenation)—specialist centers only.

Question 28

Mechanical Ventilation in ARDS

Answer 28

Low tidal volumes and frequent breaths

PEEP—very important

Question 29

Pharmacological Therapy

Answer 29

Antibiotics, if indicated (sepsis)
Bronchodilators and mucolytics
IV corticosteroids: minimize inflammatory response
Nitric oxide (pulmonary vasodilator-gas attached to ventilator—v. expensive)
Sedation
Neuromuscular blocking agents

Question 30

Nutritional Support

Answer 30

Enteral feeding benefits
Balanced caloric, protein, carbohydrate, and fat intake
Usually require 35 to 45 kcal/kg/d
High carbohydrates avoided to prevent excess carbon dioxide production

Question 31

Complications

Answer 31

Sepsis/SIRS
Volutrauma
Pneumothorax (stiff lungs)
Pneumomediastinum
VAP
Immobility 
DVT/PE

Question 32

Conditions requiring a chest tube.

Answer 32

Pneumothorax-can be open or closed.

Open-chest wall is breached e.g stab wound
Closed-chest wall is intact e.g spontaneous pneumothorax or after central line insertion

Hemothorax
Hemopneumothorax
Pleural effusion: Lung cancer patients
Empyema
Chylothorax
Tension pneumothorax: medical emergency

Question 33

Tension Pneumothorax

Answer 33

As the fluid or air builds up in the pleural space, the lung on the affected side collapses. The increased pressure in the thoracic cavity causes the heart and trachea to “SHIFT” away from the accumulated air/fluid (mediastinal shift).

This is called a TENSION PNEUMOTHORAX and is a medical emergency!
The patient will go into Pulseless Electrical Activity.

Question 34

Signs & Symptoms of Pleural Abnormalities

Answer 34

Pain
Dyspnea and tachypnea
Low O2 saturation
Cough
Dullness to percussion and decreased breath sounds over affected area
Tactile fremitus-vibration of the chest wall that can be felt with the hand
Crackles over area with fluid accumulation

Question 35

Common Causes of Air or Fluid in the Pleural Space

Answer 35

Medical/surgical:
Surgical procedure involving the thorax e.g. open heart surgery
Accidental puncture of the pleura during surgery
Pneumothorax caused by central line insertion
High ventilator pressures leading to pneumothorax
Accidental puncture of thoracic duct leading to chylothorax (rare)

Question 36

Chest tube use after lung surgery

Answer 36

After pneumonectomy, USUALLY no chest tube is placed. This allows the space to fill up with fluid.

The pt will have one or more chest tubes following a lobectomy or wedge resection.

Pleurodesis-chemicals are instilled into the pleural space to stick the visceral and parietal layers together usually for an unresolvable empyema or pleural effusion. The pt will have a chest tube post-op.

Question 37

Chest Tube Insertion

Answer 37

Sterile procedure.

Position patient:
Pneumothorax-high Fowler’s. AIR RISES! Chest tube is inserted into 2nd or 3rd intercostal space, midclavicular line on the anterior chest.

Pleural effusion or Hemothorax- sit on side of bed and lean on several pillows on bedside table if possible. FLUID SINKS! The chest tube will be inserted midaxillary line, 4th intercostal space or lower.

Question 38

DRY SUCTION

Answer 38

This has a drainage chamber, a water seal chamber and a MECHANICAL suction regulator. There is a connector on top of the unit that attached to WALL suction.

The amount of suction applied is determined by the DIAL on the front of the unit. It does not matter how high you turn the wall suction!

These units have a suction indicator on the front—usually an orange ball—that floats up and stays visible to let you know that the suction is working. If this ball disappears, check the suction tubing for disconnection. You only have to turn the suction regulator on the wall up high enough to make the ball float up!

This is the most common type

Question 39

Air leaks and fluctuations

Answer 39

If the patient has a pneumothorax, when he breathes, the inhaled air passes from his lung through the hole in the damaged tissue, to the pleural space, then down the chest tube. This will cause bubbles to be seen in the water seal chamber. It will also cause the water to rise and fall with each breath in and out(tidaling)

When the airleak is gone and the water no longer fluctuates, the damaged lung tissue has healed and air is no longer accumulating in the pleural space

Question 40

Care of Chest Tubes

Answer 40

Notify MD/NP immediately if drainage is more than 200mls/hour or changes in character. Also notify if drainage suddenly stops—a blocked chest tube leads to tension pneumothorax/cardiac tamponade quickly in a post-op patient.

Change drain when full-you cannot empty it.

Check for kinks in the tubing. Be careful when pt in recliner chair-when they sit up, the tubing gets trapped in the chair mechanism!

Check suction regulator.

Question 41

Clamping Chest Tubes

Answer 41

NEVER clamp a chest tube for more than a minute. The only reasons to clamp it off are when the drainage container is being changed, the chest tube is being removed, or you are assessing the system for leaks.

Chest tubes DO NOT need to be clamped because the patient gets out of bed or is transported to another area.

When clamped, pressure builds up in the pleural space and the patient can get a tension pneumothorax!!

Question 42

Removing a chest tube

Answer 42

Painful-premedicate patient with Morphine or similar drug.
Sit patient in Fowler’s or semi-Fowler’s position.

Chest tube is removed in one smooth movement. Several schools of thought on timing of removal. Can be done at peak inspiration-have pt hold breath so no air enters the hole as tube is removed, or have pt exhale completely and bear down (Valsalva).

Place vaseline gauze dressing and 4x4 dry gauze over site IMMEDIATELY. Apply pressure for a minute then tape SECURELY.

Obtain CXR 4-6 hours later to check for air/fluid re-accumulation in pleural space.

Question 43

Heimlich Valve

Answer 43

This a rubber one-way valve within a rigid tube.
It can be attached to the end of a chest tube and allows air to escape but not re-enter.

This is only used for patients with a pneumothorax who have NO DRAINAGE of fluid.