Mounier-Kuhn Syndrome- A Rare Case Report

Mounier-Kuhn syndrome (M-K Syndrome) also known as Tracheobronchomalacia (TBM) often seen in middle aged and elderly people. Weakness of the tracheal and bronchial walls allows the posterior and anterior walls to draw nearer together during expiration and coughing, producing a varying obstruction. The main complaints are dyspnea, cough, phlegm and haemoptysis. Acquired TBM often presents with recurrent respiratory tract infections and mistreated as chronic bronchitis, pneumonia and the dyspnea, often treated as asthma, with poorer outcomes. Here, a case of 70-year-old male was presented with complaints of cough with expectoration since four months. Bronchoscopy, cineradiography, spirometry and intrabronchial pressure measurements are the diagnostic methods used. TBM is a progressive condition and to be considered in the diagnosis of obstructive pulmonary diseases and in the assessment of the functioning capacity of dyspneic patients. Treatment is conservative and symptomatic; in selected cases surgery may also be beneficial.

Initial Resistance of Carina Anastomoses with Increasing Tensile Stress: An ex vivo Model Comparing Different Suture Techniques

Background: After resection of the carina with a length of more than 4 cm, anastomoses often need to be performed under tension despite maximum mobilization. If the patient cannot be extubated, the anastomosis remains under continued stress. Anastomoses of the carina can be constructed using various suture techniques, including single interrupted sutures, back wall running but front wall single interrupted sutures, and complete running suture. This experimental study was designed to determine the most tensile stress-resistant anastomotic suture technique. Materials and Methods: Isolated preparations of tracheobronchial trees were recovered from freshly slaughtered pigs. Resection of the carina was carried out in preparation of the experiments. After blind randomization, anastomoses (n = 15 per group) between the distal trachea and the proximal left main bronchus were performed with PDS 4-0 employing three different suture techniques: (1) single interrupted sutures, (2) back wall running but front wall single interrupted sutures (= mixed technique), and (3) complete running suture. The anastomotic specimen was fixed onto a specially constructed device. The tracheal end was intubated with a tube (CH 8.0) and connected to a respirator. Different weights were attached to the distal end of the preparation via a clamp and guide rollers. Airtightness was investigated at the following tensile loads: 0, 500, 1,000 and 1,500 g. Intrabronchial pressure was increased in 5-mbar steps. In an underwater trial, we analyzed whether anastomoses were airtight at a maximum intrabronchial ventilation pressure of 70 mbar. Results: At an intrabronchial pressure of 25 mbar without tensile stress, all anastomoses were initially airtight. In tensionless anastomoses at 70 mbar, 100% of single interrupted and continuous sutures were airtight, as compared to 80% of sutures in mixed technique. At 70 mbar and tensile loads of 1,500 g, 80% of single interrupted sutures, 60% of sutures in mixed technique and 53% of the running sutures remained competent. Conclusion: If tracheal anastomoses can be performed without tension, the suture technique is not important. With increased tension, anastomoses performed in single interrupted suture technique were clearly superior. Thus, in situations, where high tensile stress is to be expected, single interrupted sutures should be preferred.

Peribronchial pressure in excised dog lungs

To characterize the stresses which determine bronchial diameter in the lung, we estimated peribronchial pressure (Px) relative to intrabronchial pressure (Pbr) and to alveolar pressure (PA) for the main lobar bronchus of excised dog lobes using the technique of Takishima et al. (J. Appl. Physiol. 38: 875--881, 1975). The recoil of the bronchial wall, Pbr---Px, when smooth muscle was relaxed varied primarily with bronchial diameter. The recoil of the parenchyma around the bronchus, Px---Pa, varied with lung volume but was also diameter-dependent and served to double approximately the effective elastance of the bronchus in situ. We estimated recoils during slow deflations from TLC with the bronchus untreated, or pharmacologically contracted or relaxed. In untreated and relaxed states, local parenchymal and bronchial recoils were of similar magnitude to overall lung recoil (i.e., Px congruent to Ppl) except at high inflating pressure (PA -- Ppl = 30 cmH2O) where they were about half as great. With contraction, bronchial and local parenchymal recoils increased to as much as twice overall lung recoil. Contracted smooth muscle exerted a radial stress of 36+/-14 cmH2O at full lung inflation but much less during stepwise deflation.

Measurement of intrabronchial pressure in man

By measuring total and lateral airway pressures in intact normal man, simultaneously with esophageal pressure, volume, and flow, it was possible to estimate the pressure difference across the wall of the airway, the pressure-flow curves of various segments of the airway, and the compliance of the airway. The results showed that: 1 Expiratory airway compression only occurs between the segmental bronchi and the glottis at volumes between 75 and 25% VC. 2) Expiratory flow is limited by compression of these airways. 3) The resistance of airways between segmental bronchi and trachea is variable, being markedly affected both by lung volume and pleural pressure. Tracheal resistance varies little with lung volume, but considerably with pleural pressure. The resistance of the airways between alveoli and segmental bronchi varies with lung volume but little with pleural pressure. These are probably the major resistance airways during quiet breathing. 4) Airway compliance is inversely related to lung volume. 5) The Bernouilli effect is large in large airways and helps to limit expiratory flow. bronchial pressure; airway resistance; airway compliance; maximal expiratory flow; equal pressure point; lung mechanics; airway compression Submitted on November 5, 1964