[A new rigid bronchoscope with a measuring tube for pressure and capnometry]. / Ein neues starres Bronchoskop mit Messröhre für Druck und Kapnometrie.

BACKGROUND: Pulmonary gas exchange under jet ventilation is usually controlled by pulse-oxymetry and blood gas analysis. Capnometry is not common in clinical use. Rigid bronchoscopes with pressure measurements are not known. Our aim was the development of a rigid bronchoscope with a built-in tube for the online measurement of airway pressure and gas composition. METHODS: We measured the distribution of inspiratory pressure under jet ventilation over the length inside a 8 x 400 mm rigid bronchoscope in a lung model and in patients. A measuring tube was constructed for obtaining representative values of airway pressure and capnometry. Using a prototype of a new rigid bronchoscope with the built-in measuring tube (R. Wolf Company, Knittlingen, Germany) inspiratory pressure and expiratory CO2 were measured during interventional bronchoscopy. The measuring tube was connected to the pressure control port of the jet ventilator. We applied jet ventilation with frequencies of 10 to 12 pulses per minute. RESULTS: The inspiratory pressure reaches after 10 cm distally the instrumental port a significant constant plateau. Via the built-in measuring tube representative measurement of pressure and gas can be made there. The correlation between arterial CO2 (paCO2) and expiratory CO2 (petCO2) was excellent (r = 0.96). To maintain normocapnia in 25 patients undergoing interventional bronchoscopy, the jet pressure had to be adjusted to values between 0.5 and 3.5 bar (median 2.5 bar). The responding inspiratory pressure varied from 3 to 25 mbar (median 15 mbar). A flexible bronchoscope in the working channel raises the airway pressure from 18 to 23 mbar. The automatic interruption of the jet-pulses by connecting the measuring tube to the pressure control port of the ventilator in order to prevent a barotrauma was found feasible. CONCLUSIONS: Simultaneous online control of airway pressure and gas is possible with the new rigid bronchoscope. Pressure depending jet ventilators can be controlled via the measuring tube to minimise the risk of barotrauma.

[High-dose, stereotactic, one-time radiotherapy with curative intent for peripheral lung cancer]. / Hochdosierte stereotaktische Einzeitbestrahlung mit kurativer Intention bei peripherem Bronchialkarzinom.

In peripheral non small cell lung cancer without metastasis, surgical resection achieves 5-year survival rates of at least 65%. In functionally inoperable patients radiation therapy offers the second best changes. However, in cases of severe emphysema with severely limited lung function even conventional radiation therapy is prohibited because of possible fibrotic reactions of the lung parenchyma. For such patients high dose rate stereotactic one-time radiation therapy may be an option. According to the study protocol of the DKFZ Heidelberg a dose rate of 24 Gy at the iso-center is applied with the linear accelerator in a single session. The recognisable tumour is irradiated with 22 Gy (90% isodose included). 20 Gy are applied to the tumour plus 6 millimeters safety margin. Prerequisites of such a therapy are a detailed computer-based planning using CT scans and an exact positioning with immobilisation of the patient. The irradiation is ideally performed under general anesthesia with high-frequency jetventilation to avoid movements due to breathing. We report on this new therapeutic modality in a patient with lung emphysema having a T2 tumour.

[A new single-lumen endobronchial tube for artificial respiration following pneumonectomy in thoracic surgery]. / Neuer Einlumenendobronchialtubus zur Beatmung nach Pneumonektomie in der Thoraxchirurgie.

If a patient who has undergone a major resection such as a pneumonectomy or radical pneumonectomy develops during the postoperative period respiratory failure requiring mechanical ventilation, this may cause problems with the respirator treatment. It is of particular interest that the newly sutured bronchus stump can be protected from high ventilation pressures. Until now, patients who have undergone pneumonectomy have been ventilated using a single lumen tube or a double lumen tube (Table 1). A major complication often leading to death is a bronchial stump dehiscence giving rise to a bronchopleural fistula on the operated side due to aggressive mechanical ventilation. Therefore, we developed a new single lumen endobronchial tube (produced by Willy Rüsch AG, W-7050 Waiblingen, Germany, Cat.No. 115900) for the mechanical ventilation of pneumonectomised patients (Fig. 1). The sutured bronchial stump lies between the bronchial and tracheal cuff (Fig. 2) and for that reason is not exposed to any increased ventilation pressure. This new tube contributes to a lower complication rate in mechanically ventilated patients after pneumonectomy.

[Pulse oximetry monitoring of single lung anesthesia in non-cardiac thoracic surgery]. / Pulsoximetrische Uberwachung der Eine-Lunge-Anästhesie bei nichtkardialen thoraxchirurgischen Eingriffen.

The pulse oximeter provides continuous and non-invasive measurement of the arterial oxygen saturation. Pulse oximetry contributes to safer patient management because of the immediate availability of oxygen saturation values. This is particularly important in high-risk anaesthesia such as one-lung anaesthesia. Pulse oximetry is as important as ECG monitoring and invasive blood pressure monitoring and should therefore be a standard monitoring technique in thoracic surgery. With a pulse oximeter it is possible to efficiently monitor anaesthesia during one lung ventilation thereby avoid hypoxia with its life-threatening complications.

[The effect of AR-L 115 BS on contractility dynamics of the isolated, metabolically supported dog heart (author's transl)]. / Die Wirkung von AR-L 115 BS auf die Kontraktionsdynamik des isolierten, metabolisch unterstützten Hunde-Herzens.

In this study the contractility dynamics of the left ventricle are analysed independent of respiration, pre- and afterload, heart rate and perfusion pressure. These parameters alter varyingly following the administration of 2-[(2-methoxy-4-methylsufinyl)phenyl]-1H-imidazo[4,5-b]pyridine (AR-L 115 BS) so that the study plan selected must take these factors into account. The model employed consisted of a metabolically supported isolated pulsating dog's heart. The dose of AR-L 115 Bs used was 0.125 mg/kg body weight and it was infused over a period of 30 min. Altogether the study demonstrates that AR-L 115 BS has a marked positive inotropic effect on the isolated heart even under the conditions of infusion. The coronary resistance diminishes and the cardiac output increases.