Effect of PEEP and suction via chest drain on functional residual capacity and lung compliance after surgical repair of congenital diaphragmatic hernia: preliminary observations in 5 patients.

BACKGROUND/PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with pulmonary hypoplasia that limits survival. The authors' knowledge on lung mechanics and lung volumes in these patients with hypoplastic lungs is still limited. Therefore, the authors performed measurements of functional residual capacity (FRC), compliance of the respiratory system (CRS), and tidal volume in 5 full-term infants (gestational age, 38 to 40 weeks; birth weight, 2,800 to 3,530 g) before and after surgical repair of neonatal CDH. METHODS: The authors studied the influence of different levels of positive end-expiratory pressure (PEEP) and suction via inserted ipsilateral chest tube connected to a water seal on lung volume and lung mechanics. A computerized tracer gas (SF6) washout method was used for serial measurements of FRC. Compliance of the respiratory system was determined according to insufflatory method. RESULTS: The authors found a preoperative compliance between 1.5 and 3.9 mL/kPa/kg and a preoperative FRC between 9.1 and 12.9 mL/kg indicating severe hypoplasia of the lungs in all patients. Immediately after surgical repair of CDH, compliance decreased to 85% (78% to 91%) of preoperative value, and FRC increased to 132% (110% to 150%) of preoperative value under mechanical ventilation while at 4 cm of water of PEEP and at -10 cm of water of suction via chest drain with the need of high fraction of inspired oxygen. After reduction of PEEP from 4 to 2 or 1 cm of water and lowering suction from -10 cm of water to -2 or 0 cm of water FRC decreased to 103% (80% to 122%) of preoperative value and compliance, and tidal volume improved to 135% (110% to 147%) of preoperative value resulting in increased alveolar ventilation, correction of acidosis and improvement in oxygenation. During the first days after surgery inadequate high PEEP or strong suction via chest tube drainage resulted in increase in FRC paralleled by decrease in compliance indicating overdistension of these hypoplastic lungs. CONCLUSIONS: The data show that overdistension of hypoplastic lungs in infants with CDH can be detected and excluded by repeated measurements of FRC and compliance in these critical ill infants. These data might help setting appropriate ventilator parameters, adequate suction via chest drain, and thereby improve gas exchange and outcome.

Influence of inspiratory capacity on bronchodilatation via Turbuhaler or pressurized metered-dose inhaler in asthmatic children: a comparison.

This study was designed to compare the bronchodilatatory effect of terbutaline inhaled through Turbuhaler (TH) or pressurized metered-dose inhaler (pMDI) in young asthmatics, and to assess the possible relationship between patients' inspiratory capacity and bronchodilatation for both devices. One hundred and eighteen asthmatics (aged 4 10/12-20 6/12 years) with bronchial obstruction (mean Vmax 50%: 59.5% pred, SD 17.8% pred) were allocated at random to two groups of 59 patients to inhale 0.5 mg terbutaline either by TH or by pMDI (and placebo by dummy of the other device). In- and expiratory spirometry and bodyplethysmography were conducted before and 10 min after inhalation. Bronchodilatation was effective [change in airways resistance (delta RAW) -50%, change in forced expiratory volume in 1 s (delta FEV1)+15%, delta Vmax 50% or 25% + 25% of baseline] in 41 of 59 patients with pMDI (69.5%) and 33 of 59 patients with TH (55.9%). The effect on Vmax 50% was significantly better with pMDI than with TH. Turbuhaler users with higher inspiratory flow [forced inspiratory volume in 1 s (FIV1), forced inspiratory flow at 50% vital capacity (FIF50)] reached better bronchodilatation, while bronchodilatatory effect was not correlated with inspiratory performance in MDI users. Peak inspiratory flow (PIF) did not correlate well with bronchodilatation by TH. When using TH for bronchodilatation, the effectiveness of terbutaline depends upon the degree of inspiratory capacity. This can lead to impaired bronchodilatatory effect in subgroups of obstructive young asthmatics with low inspiratory flow. In contrast, when using a pMDI, inspiratory capacity does not seem to influence the effectiveness of terbutaline.

[Allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis (CF): clinical significance, diagnosis and therapy]. / Die allergische bronchopulmonale Aspergillose (ABPA) bei Patienten mit Mukoviszidose (CF): Klinische Bedeutung, Diagnostik und Therapie.

Intermittent or long term treatment with antibiotics, progredient destruction of the lungs as well as dystrophy of individuals are predisposing factors for the colonization of the respiratory tract with Aspergillus fumigatus in CF patients. Allergic bronchopulmonary aspergillosis (ABPA) is a significant problem in CF patients. It has been reported with an incidence of 10%. The diagnosis of ABPA in patients with CF is difficult since it is common for both diseases to have several of the same clinical and laboratory features. Prednisolone with an initial dose of between 0,5-1,0 mg/kg/day remains the treatment of choice for ABPA. The doses reduction and the duration of the treatment depend on clinical findings and on serum IgE levels.