Nasal masks

Continuous positive airway pressure Therapy delivered using a nasal mask to improve the patency of the upper airway by maintaining sufficient air pressure to alleviate sleep-disordered breathing. 

Noninvasive positive-pressure ventilation (NPPV) provides ventilatory support with oxygen and pressurized airflow using a face or nasal mask with a tight seal but without endotracheal intubation. In patients with acute respiratory failure due to COPD exacerbations, NPPV was associated with lower mortality, lower intubation rates, shorter hospital stays, and greater improvements in serum pH in 1 hour compared with usual care. Use of NPPV reduces the complications that often arise with invasive mechanical ventilation. NPPV is not appropriate for patients with altered mental status, severe acidosis, respiratory arrest, or cardiovascular instability. 

End-tidal C02 is monitored in conscious rats by using a mask that is fitted to the snout of the rat. Since rats are obligate nasal breathers, enclosure of the mouth is not necessary. The distal tip of the nasal mask has an opening (I.D. = 3.5 mm) for breathing... 

Patients are usually asymptomatic during dialysis-associated hypoxemia, unless they have severe cardiac or pulmonary disease. The hypoxemia can be corrected by using a bicarbonate dialysate, a biocompatible dialyzer, or the administration of 02 by nasal mask or cannula (C2). 

Strumpf DA, Millman RP, Carhsle CC, et al. Nocturnal positive-pressure ventilation via nasal mask in patients with severe chronic obstructive pulmonary disease. Am Rev Respir Dis 1991 144 1234-1239. 

Benhamou D, Muir JF, Raspaud C, et al. Long-term efficiency of home nasal mask ventilation in patients with diffuse bronchiectasis and severe chronic respiratory failure a case-control study. Chest 1997 112 1259-1266. 

There are three main types of ventilator circuits used for HMV Single circuits with a leak, single circuits with a valve, and double circuits with a valve. When used with NIV, it is important that the appropriate mask be used. Table 5 summarizes the important points associated with each type of circuit. Circuits with a leak are used for bi-level devices. The intentional leak and CO2 washout for a given pressure vary significantly depending on the manufacturer and the type of mask. There are many choices of masks for the leak circuit as these masks are also used for CPAP. We have already reviewed the issue of CO2 washout and concluded that this is not a major concern when using a nasal mask (20). The only type of mask where this might be of clinical concern is with a full-face mask. A fiill-face mask is... 

Sanders MH, Kem N. Obstructive sleep apnea treated by independently adjusted inspiratory and expiratory positive airway pressures via nasal mask. Physiologic and clinical implications. Chest 1990 98 317-324. 

Made of hypoallergenic material Low resistance to airflow Reduced dead space Anti-asphyxia valve (oro-nasal mask). Swivel connector with 360° rotation Inexpensive Easy to clean... 

External nasal masks are attached around the nasal pitma, thereby assuring minimal facial contact and no pressure on the bridge of the nose. 

The site of the exhalation port affects CO2 rebreathing (37,38) with more effective CO2 clearing when the exhalation port is located within the oro-nasal mask. 

Oro-nasal masks may be preferred, in the presence of significant mouth breathing. Moreover, the improvement in arterial blood gases is less (26) and slower (35) with the... 

ESOro-rtasal mask Nasal mask Nasal pillows... 

Figure 1 Rate of use of three different noninvasive interfaces (oro-nasal mask, nasal mask, nasal pillows), as reported by the studies where noninvasive ventilation was utilized to treat acute left) and chronic (right) patients. The oro-nasal mask is the interface of choice in patients with acute or acute on chronic ventilatory failure, while it is less commonly employed for domiciliary treatment of stable chrcniic ventilatory failure. The nasal mask is preferred for long-term treatment of chronic patients. Source From Refs. 39 and 40.

Figure 11 Mechanical insufflation-exsufflation provided via an oral-nasal mask in a monitorized patient with neuromuscular disease.

Zaccaria S, Braghtroli A, Sacco C, et al. Central hypoventilation in a seven year old boy. Longterm treatment by nasal mask ventilation. Monaldi Arch Chest Dis 1993 48 37-38. 

Ellis ER, Bye FTP, Bruderer JW, et al. Treatment of respiratory failure during sleep in patients with neuromuscular disease. Positive-pressure ventilation through a nasal mask. Am Rev Respir Dis 1987 135 148-152. 

In the case of a 62-year-old woman with bilateral carotid body paraganglioma (19) and central alveolar hypoventilation—who received mechanical ventilation in 1990 with negative pressure through a poncho wrap and subsequently NIPPV through a nasal mask— two months after treatment symptoms, signs of right ventricular failure and daytime blood gases all improved. She has successfully been ventilated for 16 years. 

Guidance and management for HMV Additions depending on the equipment Tracheostomy case Nasal mask case... 

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