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INCENTIVE SPIROMETRY

• Used primarily as a preventative or prophylactic treatment
• Patient are encouraged to take slow - deep inspirations ten times every hour
• Patients are taught to perform 5-10 second breath holds at maximal inhalation for each of the 10 hourly breaths

Advantages of I.S. Therapy

• Patients can self-administer as often as they like
• Relatively easy to learn and perform
• Very rare side effects
• Inexpensive way of preventing pulmonary complications

Reasons Why I.S. May Not Be Appropriate

• Patient is not alert or cannot follow instructions
• Patient cannot hold mouthpiece in their mouth
• Patient has a large atelectasis that must be treated with more aggressive measures
• Patient cannot create a large enough breath for I.S. to be of any real value

Prior to Teaching I.S. do the following:

• Check the chart for

  Order; Admitting Dx; evidence of any recent surgery (when?; type?); evidence of any previous pulmonary problems (COPD; asthma?); Chest X-ray reports

• At the bedside check for

  mental status; ability to comprehend; pain level; evidence of any pulmonary problems (tachypnea &/or S.O.B.?)

What to Focus on During I.S. Instruction

• What is I.S.
• Why is the patient going to learn how to perform it
• How often should the patient perform it
• Does the patient have any questions

Types of I.S. Devices

• Volume Oriented devices

  Actually measure & display the amount of air patient inhaled

• Flow Oriented devices

  Only display inspiratory flowrate and may attempt to estimate amount of air inhaled

Example of a Flow-Oriented Device See Egan’s Fig 35-4

INTERMITTENT POSITIVE PRESSURE BREATHS (IPPB) as Method of Enhancing Lung Expansion

• Definition - Lung expansion therapy utilizing positive airway pressure for periods of 15 - 25 minutes to enhance resting lung ventilation by increasing the patients tidal volume (Vt)
• How Positive Pressure Ventilation Differs from Normal

  In normal breathing, inspiratory pressures are negative while expiratory pressure are positive

  In IPPB, both inspiratory pressures & expiratory pressure are positive

Indications For IPPB

• Patient has an atelectasis that is not responding to I.S. therapy
• Patient cannot perform I.S. therapy
• This may also be a problem with IPPB!!
• Poor cough effort & secretion clearance due to inability to take a deep breath
• Short term ventilatory support when patient is hypercapnic
• Enhancement of aerosol medication delivery in patient unable to take a deep breath

Contraindications to IPPB

• Untreated pneumothorax
• High intracranial pressure (>15 mm Hg)
• Active hemoptysis
• Radiographic evidence of a bleb
• Nausea
• Tracheo-esophagel fistula
• Recent esophageal surgery

Hazards & Complications of IPPB

• Barotrauma (pneumothorax)
• Hyperventilation (dizziness)
• Gastric distension (secondary to air swallowing)
• Decrease in venous return (possible drop in B.P.)
• Increased airway resistance
• May actually cause bronchospasm in some patients!

Monitoring the IPPB Treatment

• What is the pulse & respiratory rate prior to treatment?
• What are the patients breath sounds; their color; respiratory effort; mental state - prior to the Tx?
• What is the patients SpO2 or peakflow before the treatment (if giving bronchodilators)

Equipment Needed for IPPB

• IPPB Ventilator

  Bennett “PR series” ventilator OR Bird “Mark series” ventilator

• IPPB tubing circuit

  “Universal” disposable circuits now used

• Additional equipment “possibly” needed

  Mouthseal & noseclips for patients who cannot use mouthpiece
  Mask (if mouthseal is not available)
  Connector for using circuit with trach patient
  

Key Elements of IPPB Instruction

• Explain what is IPPB
• Why is the patient going to be receiving IPPB treatments
• How long is each treatment & how often will they receive it
• What should they do during the treatment
• Any questions they have of you

What SHOULD the patient do during IPPB?

• Patient starts their breath; the machine cycles on
• Patient relaxes and lets the machine fill their lungs
• Patient should NOT be actively breathing after the machine cycles (turns on)
• Patient will exhale normally in a relaxed way through the mouth when machine ends inspiration (pre-set pressure is reached)

What should the therapist emphasize during the treatment?

• Make sure patients keep lips sealed tight around the mouthpiece
• Coach patient to not actively breath
• “Relax and let the machine fill your lungs!”
• Make sure patient does not breath too rapidly during treatment
• This will cause dizziness secondary to hyperventilation

Key Aspects & Terms Associated with IPPB ventilators

• Patient initiates the breath and machine is able to detect the patient’s effort and then starts delivering gas into the mouthpiece
  • The ability of machine to detect the patients need for a breath is called “sensitivity”
  • Sensitivity should be set so that machine will begin breath at a pressure that is 1 or 2 cmH2O pressure below zero (or -1 to -2 cmH2O pressure)

These machines are “pressure cycled”

• This means that inspiration ends when a preset pressure is reached in the circuit
• Preset pressure is set by the therapist
  • Typical pressure ranges (15 - 25 cmH2O)
  • Pressures higher than 25 associated with “air swallowing” particularly with mouthseal or mask treatments
  • Pressures less than 15 may be insufficient to increase the tidal volume (Vt)

Characteristics of Pressure Cycling

• Any leak in the “circuit” or in the patient will cause the machine to not end inspiration (cycle off)
• Patient can easily end the breath by
• blowing back into the mouthpiece
• putting their tongue over the mouthpiece
• Pressure cycled machine can NOT guaranteed to deliver any specific volume to the patient
• Volume delivered is based upon;
• the patients ability to relax and let the machine deliver the breath
• the pressure level set by the therapist
• the higher the pressure level set - the greater the volume delivered to the patient (ideally)

CONTINUOUS POSITIVE AIRWAY PRESSURE (CPAP)

A simple approach which maintains some positive pressure in the airway at the end of exhalation
Net effect of CPAP is that FRC is increased
• There is a high correlation between improvement of atelectasis and the patient having a higher than normal FRC

Review of Lung Volumes & Capacities

Beneficial Effects of CPAP
• Recruitment of collapsed alveoli
• The work of breathing is decreased as lung compliance (stretchability) improves
• Improvement of gas distribution
• Improvement in secretion removal

Indications for Use of CPAP

Indications for Use of CPAP
• Treatment of post-operative atelectasis
• Should be used continuously
• Has been used in the treatment of cardiogenic pulmonary edema

Contraindications to CPAP

• If blood pressure is very low
• Diastolic of < 50 mm Hg
• If patient has one or more of the following;
• Nausea
• Untreated pneumothorax
• Elevated intracranial pressure (ICP)

Hazards of the Use of CPAP

• Barotrauma (pneumothorax)
• Gastric distension
• Air-trapping
• Decrease in BP
• Can be very uncomfortable to the face of patient using mask CPAP

What Does CPAP Accomplish?

• Increases the FRC by increasing the amount of air in the chest at the end of exhalation
• The net effect of increasing FRC is to;
• Re-open any atelectatic areas
• Improve any hypoxemia that may be resulting from the atelectasis
• CPAP is also used to treat sleep apnea secondary to upper airway obstruction