N I V Update

Dean R. Hess PhD RRT Associate Professor of Anesthesia Harvard Medical School Assistant Director of Respiratory Care Massachusetts General Hospital Editor in Chief Respiratory Care Noninvasive Ventilation: Update 2010

NIV versus CPAP CPAP = EPAP = PEEP No ventilation assistance with CPAP

Mask CPAP
Obstructive sleep apnea
Cardiogenic pulmonary edema
Treat post-operative atelectasis
Acute hypoxemic respiratory failure?

Evidence for NIV COPD Exacerbations ★★★★★ Acute cardiogenic pulmonary edema ★★★★ Prevent extubation failure ★★★ Transplantation, immunocompromise ★★ Respiratory failure following lung resection ★ Acute hypoxemic respiratory failure ? Asthma ? Do not intubate/Do not Resuscitate ★ /− Failed extubation −

COPD Exacerbation
14 studies included in the review
Decreased risk of intubation: NNT 4
Lower mortality with NIV: NNT 10
Picot, Cochrane Database of Systematic Reviews 2008

Cardiogenic Pulmonary Edema
Decreased intubation: CPAP - NNT 9 NIV - NNT 14
Reduced mortality CPAP - NNT 6 NIV - NNT 8
No difference between CPAP and NIV
No additional harm (acute MI) with NIV
Vital, Cochrane Database of Systematic Reviews 2008

Post-Extubation NIV
Earlier extubation; extubate directly to NIV
Nava, Ann Intern Med 1998;128:721
Ferrer, Am J Respir Crit Care Med 2003;168:70
Prevent extubation failure in patients at risk; extubate directly to NIV
Nava, Crit Care Med 2005;33:2465
Ferrer, Am J Respir Crit Care Med 2006;173:164
Rescue failed extubation; evidence does not support
Keenan, JAMA 2002;287:3238
Esteban, N Engl J Med 2004;350:2452

Hypoxemic Respiratory Failure
NIV decreased the need for intubation and ICU mortality
Diagnoses included pneumonia, cardiogenic pulmonary edema, thoracic trauma, ARDS, severe asthma, and postoperative respiratory failure
Ferrer, Am J Respir Crit Care Med 2003; 168:1438 The literature does not support the routine use of NIV in all patients with acute hypoxemic respiratory failure. Keenan, Crit Care Med 2004; 32:2516

NIV for Acute Asthma
ED RCT of 30 patients with severe asthma
NIV group had more rapid improvement in FEV 1 and reduced hospital admission
Soroksky, Chest 2003; 123:1018

52 immunosuppressed patients with hypoxemic acute respiratory failure
NIV every 3 hrs for at least 45 min
Fewer patients in the NIV group than in the standard-treatment group required endotracheal intubation (12 vs. 20), died in the ICU (10 vs 18), or died in the hospital (13 vs 21)
N Engl J Med 2001;344:481

Crit Care Med 2005;33:1976

Nosocomial Pneumonia NIV compared with invasive mechanical ventilation patients assigned to NIV or invasive mechanical ventilation patients assigned to NIV or standard therapy Hess, Respir Care 2005;50:924

Patient Selection for NIV
Respiratory distress with dyspnea, use of accessory muscles, abdominal paradox
Respiratory acidosis; pH < 7.35 with PaCO2 > 45 mm Hg
Tachypnea; rate > 25/min
Diagnosis shown to respond well to NIV (e.g., COPD, CPE)
Step 1: Patient needs mechanical ventilation

Exclusions for NIV
Airway protection: respiratory arrest, unstable hemodynamics, high aspiration risk, unable to protect airway, copious secretions
Unable to fit mask: facial surgery, craniofacial trauma or burns, anatomic lesion of upper airway
Uncooperative patient: anxiety
Patient wishes
Step 2: No exclusions for NIV

When to Stop
Lack of improvement within 1-2 hrs
Patient intolerance of therapy
Adverse effects: hypotension
Patient wishes
When to Transfer to ICU
Failure of NIV
Mask intolerance
Better monitoring

Is NIV Appropriate? Is NIV NOT Appropriate? When To Stop?

The Interface
Mask
Nasal
Oronasal
Total face
Pillows
Mouthpiece
Helmet

nasal total face oronasal pillows mouthpiece helmet

Choice of Interface
The internal volume of masks had no short-term effect on gas exchange, minute ventilation, or effort (Crit Care Med 2009; 37:939)
Nasal versus oronasal mask: failure more often with nasal mask (Crit Care Med 2009; 37:124)
Nasal versus oronasal mask: oronasal mask better tolerated (Crit Care Med 2003; 31:468)
Nasal mask versus oronasal mask versus nasal pillows: nasal mask better tolerated; PaCO2 lower with oronasal and pillows (Crit Care Med 2000; 28:1785)
Oronasal mask versus mouthpiece: tolerance better and less staff time required for mask (Anaesthesia 2006; 61:20)

Mouth Leak
Decreased comfort
Less effective ventilation
Ineffective trigger/cycle
NIV failure (Soo Hoo 1994, Fraticelli 2009)
Increased nasal resistance (Richards 1996)
Upper airway drying (De Araujo 2000)
Disrupted sleep (Meyer 1997; Tescheler 1999)
Oronasal mask; coaching?; chin strap?

Skin Breakdown
Use correctly fitted mask
Try different interface; rotate interfaces
Adjust headgear
Duoderm
photo courtesy Dr. Nick Hill

Ventilators for NIV

Ventilators for NIV
Ventilators for NIV are typically pressure support devices: IPAP EPAP PS = IPAP - EPAP
Trigger Pressure vs volume (PCV vs PSV vs PAV) Rise time Cycle Back-up rate

AVAPS: Average Volume Assured Pressure Support
Estimates patient tidal volume over several breaths and compares it to target tidal volume
Gradually changes IPAP (0.5 – 1 cm H 2 O/min)
Similar to PRVC, Autoflow, and VS

blower & pressure controller single hose leak
Rebreathing:
Increase EPAP level ≥4 cm H2O
Increase leak in system
Fixed leak in mask rather than hose
Titrate O 2 into mask rather than hose
mask

Inhaled Bronchodilators
Nebulizer therapy inline with NIV
MDI therapy inline with NIV
Hess, J Aerosol Med 2007; 20:S85 Iosson, N Engl J Med 2006; 354:e8

Managing Dys-Synchrony
Trigger dys-synchrony
Leaks
Auto-PEEP
High levels of support
Flow dys-synchrony
Rise time
Cycle dys-synchrony
Leaks
High levels of support

Practical Application
Select appropriate patient
Choose a ventilator capable of meeting patient needs (usually pressure ventilation)
Choose interface; avoid mask that is too large
Explain therapy to the patient

Silence alarms; choose low settings
Initiate NIV while holding mask in place
Secure mask, avoid tight fit
Titrate pressure support (IPAP) to patient comfort

Titrate FIO2 to SpO2 > 90%
Avoid PIP > 20 cm H2O
Titrate PEEP/EPAP/CPAP per trigger effort and SpO2
Coach and reassure patient; make adjustments per patient compliance

Complications
Leaks
Mask discomfort and facial soreness
Eye irritation
Sinus congestion
Oronasal drying
Patient-ventilator dyssynchrony
Gastric insufflation
Hemodynamic compromise
(Complications are usually minor)

Cough Assist

NIV Success clinician skills equipment selection patient selection

N I V Update

by scribeofegypt on Feb 21, 2010

Accessibility

Categories

Tags

Upload Details

Usage Rights

2 Embeds 33

Statistics

N I V Update — Presentation Transcript

http://www.banhachest.blogspot.com	29
http://banhachest.blogspot.com	4