Exogenous surfactant

Intratracheal nebulization of salbutamol solution or bolus administration of curosurf (surfactant) reduced the mortality in guinea pig. Salbutamol appeared to be more effective than curosurf in this respect. Since SM exposure induced damage to the limg surfactant, severe bronchoconstriction, and inflammation of the respiratory tract, a combined treatment consisting of exogenous surfactant, anti-inflammatory drugs, and broncholytics may be a better choice (Van Helden et al, 2004). 

Wemhoner A, Jennings P, Haller T et al (2011) Effect of exogenous surfactants on viability and DNA synthesis in A549, immortalized mouse type II and isolated rat alveolar type II cells. BMC Pulm Med 11 11... 

TABLE 28—6. Exogenous Surfactants Used for the Treatment of Neonate with Respiratory Distress Syndrome... 

Tarczy-Homoch P, Hildebrand J, Mates EA. Effects of exogenous surfactant on lung pressure-volume characteristics during Uquid ventilation. J Appl Physiol 1996 80 1764-1771. 

Lewis IF, Brackenbury A. Role of exogenous surfactant in acute lung injury. Crit Care Med 2003 31(suppl) S324-328. 

Treatment of acute respiratory distress syndrome (ARDS) or acute lung injury may be defined as a condition involving impaired oxygenation. The nonpharmacologic therapies include mechanical ventilation. The pharmacologic therapies include the use of exogenous surfactant, corticosteroids, acetylcysteine (antioxidant), ketoconazole, nitric oxide, eicosanoids and their inhibitors, sodium nitroprus-side (vasodilator), pentoxifylline, antiendotoxin, and anticytokine therapy and antibiotics. 

Fujiwara T, Robertson B, Robertson B, Van Golde, L, Batenburg J (eds) (1992) Pharmacology of Exogenous Surfactant Elsevier, Amsterdam, pp 561-592... 

Abstract The interfacial properties of tracheal aspirate from infants with untreated neonatal respiratory distress syndrome (NRDS), and NRDS infants after therapy with the exogenous surfactant Curosurf were assessed. The interfacial characteristics of the aspirate (equilibrium surface tension, maximal and minimal surface tension during lateral compression-decompression cycles) were determined with the pendant drop method. Our results show that the tracheal aspirate of infants with untreated NRDS had high equilibrium, maximal and minimal surface tension values. In contrast, the samples from infants, treated with Curosurf , showed lower surface tension values, suggesting that the application of Curosurf improves the composition and the properties of the pulmonary surfactant in the infant lung. 

The modem NRDS therapy includes the use of different native or synthetic exogenous surfactants (ES), like the native surfactant Curosurf . ES function as analogues for normal human AS. The main characteristics of these preparations are their strong surface activity upon spreading at the air/water interface and their specific respiratory dynamic mechanical and physical characteristics during alveolar contraction and expansion [8-12]. 

Tracheal aspirate (TA) was obtained by low volume lavage (1 ml) from intubated newborns with NRDS. Exogenous surfactant was administered in accordance with international protocols for Curosurf in the sixth postnatal hour. TA was obtained prior to and 12 hours after surfactant administration. For control the pure Curosurf dispersion was also tested. 

The dynamic characteristics of the samples studied also showed a significant improvement after the exogenous surfactant preparation application Ymax reduced from 52 mN/m before the therapy to 32 mN/m after treatment with Curosurf . The maximal surface tension of the pure preparation was 25 mN/m, i.e. tracheal aspirate values approached the parameters of the exogenous surfactant. The results are shown in Fig. 2. 

Bubble-film extractors were designed to remove dissolved endogenous and exogenous surfactants from water. These devices have found practical application for quality improvement of tap water at the points of its consumption. They were particularly useful when operating at peripheral points of long pipelines. 

Katkin JP, Husser RC, Langston C, Welty SE. Exogenous surfactant enhances the delivery of recombinant adenoviral vectors to the lung. Hum Gene Ther 1997 8(2) 171-176. 

A number of attempts to alter the course of ALI/ARDS pharmacologically have not been proven to be successful. These include the use of exogenous surfactant, glucocorticoids, antioxidant (n-acetylcysteine), prostaglandin and leukotriene synthesis inhibitors (hetoconazole, ibuprofen), prostaglandin El, inhaled nitric oxide, and pentoxifylline (159,160). Trials with antibodies aimed at blocking inflammation provoked by endotoxin, TNF-a, and IL-1 have also not been proven to be successful... 

Several studies have compared the administration of aerosols with bolus instillation of exogenous surfactant. For example, Li et al. (155) compared administration of 250 mg surfactant as an aerosol with instillation of about 25 mg in rats. Lung damage was induced initially by repeated lung lavage to deploy the animals own surfactant. Surfactant aerosol was generated by the ultrasonic nebulizer and the droplet diameter was 3.4 1.2 pm. Fresh surfactant was added to the nebulizer every 15 min to avoid changes in surface properties of the surfactant. 

Lewis JF, McCaig L. Aerosolised versus instilled exogenous surfactant in a nonuniform pattern of lung injury. Am Rev Respir Dis 1993 148 1187-1193. 

De Sanctis GT, Tomkiewicz RP, Rubin BK, Schiirch S, King M. Exogenous surfactant enhances mucociliary clearance in the anesthetized dog. Eur Respir J 1994 7 1616-1621. 

Matalon S, Holm BA, Notter RH. Mitigation of pulmonary hyperoxic injury by administration of exogenous surfactant. J Appl Physiol 1987 62 756-761. 

Taeusch HW, Clements J, Benson S. Exogenous surfactant for human lung disease. Am Rev Respir Dis 1983 128 791-794. 

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