[How to become a Respiratory Therapist in Germany - Status quo and Development Prospects]

The profession respiratory therapist is well established in Germany 10 years after the introduction. 600 participants have successfully graduated from the training facilities.Our goals are high quality interprofessional teamwork and medical assistance inclusive delegation of formerly physician activities. The duties are comparable to the work pattern of Technical Assistants in surgery. For this profession different ways of qualification are possible: primary training, advanced training and academic studies Physician Assistance. The Geman Medical Association worked up standards for a delegation model to physician assistants and relief and assictance for physicians. These standards were finalised in 2017 during the 120th german physician convention. After this decision we can estimate that the number of physician assistants will be growing up. The german respiratory society can imagine physician assistants with special knowledge in respiratory care. But we are not sure wether our previous educational courses will be completely substituted by academic studies. Temporary there will coexist different educational concepts on different levels. In one german country it is also possible for nurses to pass federal certified advanced training in respiratory care. This is why it will be hard to make a choice on this matter in the future.

[Noninvasive Mechanical Ventilation in Acute Respiratory Failure]

The non-invasive ventilation (NIV) is widespread in the clinical medicine and has attained meanwhile a high value in the clinical daily routine. The application of NIV reduces the length of ICU stay and hospitalization as well as mortality of patients with hypercapnic acute respiratory failure. Patients with acute respiratory failure in context of a cardiopulmonary edema should be treated in addition to necessary cardiological interventions with continuous positive airway pressure (CPAP) or NIV. In case of other forms of acute hypoxaemic respiratory failure it is recommended the application of NIV to be limited to mild forms of ARDS as the application of NIV in severe forms of ARDS is associated with higher rates of treatment failure and mortality. In weaning process from invasive ventilation the NIV reduces the risk of reintubation essentially in hypercapnic patients. A delayed intubation of patients with NIV failure leads to an increase of mortality and should therefore be avoided. With appropriate monitoring in intensive care NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency. Furthermore NIV can be useful within palliative care for reduction of dyspnea and improving quality of life. The aim of the guideline update is, taking into account the growing scientific evidence, to outline the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.

S2k-Guideline "Prolonged Weaning"

All mechanically ventilated patients must be weaned from the ventilator at some stage. According to an International Consensus Conference the criteria for "prolonged weaning" are fulfilled if patients fail at least 3 weaning attempts (i. e. spontaneous breathing trial, SBT) or require more than 7 days of weaning after the first SBT. This occurs in about 15 - 20 % of patients.Because of the growing number of patients requiring prolonged weaning a German guideline on prolonged weaning has been developed. It is an initiative of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V., DGP) in cooperation with other societies (see acknowledgement) engaged in the field chaired by the Association of Scientific and Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF).This guideline deals with the definition, epidemiology, weaning categories, underlying pathophysiology, therapeutic strategies, the weaning unit, transition to out-of-hospital ventilation and therapeutic recommendations for end of life care. This short version summarises recommendations on prolonged weaning from the German guideline.

[Further training for medical specialists in respiratory medicine: how can we improve it?]

Young physicians in Germany often criticize the advanced training programme, especially the lack of structure and the insufficient rotations. The Medical Association in each Bundesland/federal state require to include a proposal for advanced training and rotation in a trainer's aplication for an educational license. However, there is no systematic scrutiny of these concepts and therefore the criteria stated outcomes are often only incompletely met. Trainers engage too little in training methods and medical didactics. They rarely evaluate learning outcomes, and structured assessments based on workplace are exceptions. The reasons are deeply rooted in Germany's education system: Resources for specialist training are not provided, and there is no funding for a commitment in continued medical education. In addition, teaching is not assigned a quantifiable value. However, during the last decade awareness has arisen that good training programmes are an important part of quality assurance and the validation of a hospital. Better planning, structuring and evaluation of training programmes is necessary. New learning methods should be incorporated in training programmes. The German Respiratory Society (DGP) wishes to contribute to the improvement of advanced training: for example with "train the trainer" seminars for teachers, with a structured educational course programme for the trainees, with assessments such as the HERMES (Harmonized Education in Respiratory Medicine for European Specialists) exam and with support for the accreditation as a Respiratory Training Centre of the ERS (European Respiratory Society) and EBAP (European Board for Accreditation in Pneumology).

[Prolonged weaning: S2k-guideline published by the German Respiratory Society]

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by insufficiency of the respiratory muscles and/or lung parenchymal disease when/after other treatments, i. e. oxygen, body position, secretion management, medication or non invasive ventilation have failed.In the majority of ICU patients weaning is routine and does not present any problems. Nevertheless 40-50 % of the time during mechanical ventilation is spent on weaning. About 20 % of patients need continued MV despite resolution of the conditions which originally precipitated the need for MV.There maybe a combination of reasons; chronic lung disease, comorbidities, age and conditions acquired in ICU (critical care neuromyopathy, psychological problems). According to an International Consensus Conference the criteria for "prolonged weaning" are fulfilled if patients fail at least three weaning attempts or require more than 7 days of weaning after the first spontaneous breathing trial. Prolonged weaning is a challenge. An inter- and multi-disciplinary approach is essential for weaning success. Complex, difficult to wean patients who fulfill the criteria for "prolonged weaning" can still be successfully weaned in specialised weaning units in about 50% of cases.In patients with unsuccessful weaning, invasive mechanical ventilation has to be arranged either at home or in a long term care facility.This S2-guideline was developed because of the growing number of patients requiring prolonged weaning. It is an initiative of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V., DGP) in cooperation with other societies engaged in the field.The guideline is based on a systematic literature review of other guidelines, the Cochrane Library and PubMed.The consensus project was chaired by the Association of Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF) based on a formal interdisciplinary process applying the Delphi-concept. The guideline covers the following topics: Definitions, epidemiology, weaning categories, pathophysiology, the spectrum of treatment strategies, the weaning unit, discharge from hospital on MV and recommendations for end of life decisions. Special issues relating to paediatric patients were considered at the end of each chapter.The target audience for this guideline are intensivists, pneumologists, anesthesiologists, internists, cardiologists, surgeons, neurologists, pediatricians, geriatricians, palliative care clinicians, nurses, physiotherapists, respiratory therapists, ventilator manufacturers.The aim of the guideline is to disseminate current knowledge about prolonged weaning to all interested parties. Because there is a lack of clinical research data in this field the guideline is mainly based on expert opinion.

[The respiratory therapist]

Because of the expected significant growth in the elderly population and respiratory diseases, the topic of "delegation of physician's duties" is of increasing importance to the German health-care system. In 2004 the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V. (DGP)) established the new profession: respiratory therapist. A curriculum was defined which offers training for certified nurses and physiotherapists. Respiratory therapists evaluate, treat, document and care for patients with pulmonary disorders. Under appropriate supervision a licensed respiratory therapist performs some of the work previously done by physicians at the same quality of care. The first respiratory therapists have finished their professional training in Germany. Most of these respiratory therapists are now employed in hospital-based positions requiring their specific skills. Generally, the increased medical responsibility and the increased degree of decision-making possibilities associated with the new profession contribute to a better job satisfaction. However, this is not yet true for all the newly employed respiratory therapists. Only few of the new graduate respiratory therapists were awarded higher salaries. It is a strongly recommendation to the heads of medical departments and the human resources managers of hospitals that they should recognise the increased qualifications of nurses and physiotherapists who become respiratory therapists by appropriate remuneration.

[Care of patients under mechanical ventilation at home and in nursing home conditions. Position paper of the German Medical Associations of Pneumology and Ventilatory Support ("Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V." and "Arbeitsgemeinschaft für Heimbeatmung und Respiratorentwöhnung e. V.")]

The advances in intensive and critical care medicine have not only improved the prognosis of patients with acute respiratory failure but have also increased the number of ventilator-dependent patients. The continuously increasing number of patients, the differentiation of care-giving institutions and the technical progress make it necessary to re-evaluate the quality of health care in weaning centres and outpatient care of patients on long-term ventilation. Therefore, the German medical associations of pneumology and ventilatory support, "Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e. V." and the "Arbeitsgemeinschaft für Heimbeatmung und Respiratorentwöhnung e. V.", wish to present this actual position paper. However, scientific guidelines are in preparation.

[Management of secretion in patients with neuromuscular diseases]

BACKGROUND

Many patients with neuromuscular diseases suffer from a weak cough. Due to infection or aspiration a life-threatening situation may occur. There are different options for the therapists to improve secretion clearance from the airways in the patient with a weak cough. Furthermore, there are indications that consequent practice of techniques to ameliorate bronchial clearance may also improve the prognosis of patients with neuromuscular diseases.

MANAGEMENT

The management of secretions in neuromuscular disorders does not consist of single actions but is rather a complex programme. Diagnostics and several therapeutic measures have to be performed intensely and regularly. The diagnosis of a weak cough flow is based on anamnestic data, e. g., increase in secretions or dysphagia, physical examination, e. g., paradoxical breathing, and easily measured lung function parameters like vital capacity and peak cough flow (PCF). The diagnosis of an accumulation of secretions in the airways can be made easily by means of a pulse oximetry: while breathing room air the oxygen saturation in the case of a healthy lung and clean airways will be better than 95 %. A decline can, among others, be induced by amounts of secretions in the airways. The consequence should be measures to improve secretion expectoration (so-called oximetry-feedback protocol). To assist in secretion elimination from the airways several means are available like air stacking, manually assisted cough and mechanical assisted coughing--e. g., mechanical insufflator-exsufflator. Which of these techniques should be used depends on the extent of the disease: with preserved facial and bulbar muscles, air stacking alone or in combination with manually assisted coughing may be adequate and effective in the home care of the patient. In case of failure of these means, e. g., in bulbar paralysis, there is the possibility to apply mechanically assisted coughing by means of the mechanical insufflator-exsufflator. In case of tracheostomy, air stacking or mechanical assisted coughing has to be combined with tracheal suctioning. Acute infections of the lower airways are a special challenge: personnel intensive application of a combination of different secretion eliminating techniques, e. g., bronchoscopy in the hospital, manually assisted coughing and mechanically assisted coughing have to be performed in high intensity to avoid intubation.

CONCLUSION

The early diagnosis of a weak cough in NMD patients is important for the timely start of existing and effective measures for improving the capacity of elimination of secretions--air stacking, manually assisted cough and mechanically assisted cough. Although there is no high degree of evidence, we believe that morbidity and possibly mortality can be affected in a positive manner.

Beatmung bei akuter ventilatorischer Insuffizienz

Acute ventilatory insufficiency is characterized by hypercapnia, respiratory acidosis and secondary hypoxemia. The primary target of mechanical ventilation is improvement of alveolar ventilation, that means compensation of the ventilatory insufficiency. Noninvasive ventilation started as ventilatory support during the big polio epidemic, at that time in form of negative pressure ventilation. In the last two decades NIV is in form of positive pressure ventilation important for long-term ventilation at home, but there is also growing importance of NIV in the treatment of acute respiratory insufficiency in the intensive care unit. Main indication is the hypercapnic ventilatory failure in acute exacerbation of COPD. This paper will discuss ventilator therapy in general but also the data regarding the role of NIV in the treatment of hypercapnic failure. Specific points like interfaces, indications and contraindications of NIV are addressed.

[Recommendations for the treatment of respiratory complications in case of a viruspandemic]

In case of a viral pandemic without availability of effective vaccination, one can expect to be faced with additional 250 to 300 new admissions per hospital per week given the worst case scenario. Major complications are expected to occur in the respiratory system with the focus on viral pneumonia often complicated by bacterial superinfection. Frequently these patients will require artificial ventilation. The present infrastructure will not be capable of dealing sufficiently with such high numbers of casualties. These recommendations of the German Society for Pneumonology are based on the successful application of non-invasive ventilation for acute respiratory failure in recent years. It is of importance to achieve effective treatment by the use of relative simple means. The recommendation proposes to use a separate building in order to realize quarantine. In terms of diagnostic tools, a simple x-ray apparatus should be available. To monitor patients pulsoxymetry and ECG devices should be sufficient in most cases. For the treatment of acute respiratory insufficiency a sufficient number of ventilators, masks, tubing systems and filters should be kept in stock. In terms of medical treatment antibiotics to treat superinfections are of major importance. Analgesics, sedatives and intravenous fluids will also be needed. Oxygen should be available for every single patient. The recommendation gives detailed advise for the enforcement of hygiene control, diagnostic as well as therapeutic steps for in hospital treatment of high numbers of casualties of a viral pandemic.

[Respiratory therapist: introduction of a new profession]

Respiratory therapists are healthcare professionals taking care of patients with pulmonary disorders. They are an allied health specialty, practicing under medical direction. The professionalism of nurses and therapists must grow up to act successfully in new fields of medicine, where evidence-based independent action is necessary. Specialized therapists can help us coordinate separated processes (diagnoses, therapy and nursing). The profession "Respiratory Therapist" was created in the United States 50 years ago. We intend to introduce this profession also in Germany. We follow many other countries who have already taken this step. We hope that we can reach yet a higher quality of patient care.

[Noninvasive intermittent self ventilation in chronic respiratory insufficiency]

Corresponding to the two compartments of the respiratory system (lungs and ventilatory pump), two different forms of respiratory insufficiency can be distinguished on a pathophysiologic basis: disturbances of gas exchange with primary oxygenation failure (hypoxemia) due to pulmonary diseases and reduced ventilation of the lungs (hypoventilation) with primary elevated arterial carbon dioxide partial pressure (hypercapnia) and secondary hypoxemia due to disorders of the ventilatory pump. Different methods can be employed in the diagnosis of respiratory insufficiency, e.g., spirometry, blood gas analysis, nocturnal monitoring with capnography, or transcutaneous pCO2 registration and measurement of mouth occluding pressure. Therapeutic measures for respiratory insufficiency are based on two treatment principles: long-term oxygen therapy to improve hypoxemia and noninvasive ventilation therapy to improve hypercapnia and concomitant hypoxemia. The indication for long term ventilation depends on subjective complaints, objective measurement parameters, disease course, and other disease symptoms. The most frequent indications for home mechanical ventilation are diseases with restrictive ventilatory defects, especially chest wall disorders and neuromuscular disorders.

["Ondine's curse" in adults]

The term "Ondine's curse" is normally used for congenital central hypoventilation in children. We report on 10 adult patients with this disorder (average age 46 y), who were treated from 1990 to 1996. They were hypercapnic while awake (mean 57 Torr) and during sleep (mean 87 Torr). The CO2-rebreathing response was negative. During exercise test minute ventilation volume did not rise adequately (mean pCO2 : 63 Torr, mean pH: 7.21). Five of these patients underwent emergency intubation before diagnosis, 2 presented with hypoventilation syndrome and 2 with decompensated cor pulmonale, 1 was diagnosed without complaints. 8 patients needed intermittent positive pressure ventilation therapy, 7 of them noninvasive, 1 via tracheal canula. One female patient has already died, the others are under stable clinical condition with the underlying central disorder remaining unchanged. Only 2 patients showed central defects visible in magnetic resonance tomography.

[Limitations of noninvasive mask ventilation in acute hypoxemic gas exchange disorders (COPD)]

The benefit of noninvasive mask ventilation (NIMV) compared to mechanical ventilation after intubation is proven in patients with acute exacerbation of COPD. Contrary to this point the benefit is not clear in patients with acute gas exchange failure, such as in pneumonias. We tried to evaluate the efficiency of NIMV in this indication in a clinical case series. We treated 31 patients with acute gas exchange failure (pO2 52 +/- 11 Torr, APACHE II Score 20 +/- 7) with NIMV. In 18 patients (58%) blood gases improved. But during the further course 2 patients were intubated, 3 patients died. In 13 patients mask ventilation was stopped because of ineffectivity. 11 patients were intubated, 8 patients died. 3 patients were not intubated for ethical reasons. The success rate is about 20% lower than in patients with acute ventilatory insufficiency. NIMV can be used in patients with severe gas exchange failure. Until now, however, no data are available proving that the method offers significant advantages over intubation and mechanical ventilation.

[Physical performance in home ventilation patients]

Since 1995 we control the physical performance of our NMV patients using the six-minute walk test (6 MW). To determine the effects of ventilatory therapy on the physical performance a 6 MW was done before starting ventilatory support in 37 patients and repeated 3 (n = 33), 9 (n = 19) and 15 (n = 19) months after. Three months after the beginning of NMV therapy our patients significantly increased the distance achieved during 6 MW up to 120% and then remained stable for up to 15 months control time. We believe this effect is predominantly achieved by the ventilation therapy since no other therapy was done, especially no additional physical training. Furthermore, we studied 3 other patients ventilated for more than one year who underwent an additional physical training programme as in COPD patients for rehabilitation. The effects of this training were controlled by a 6 MV and by the determination of the VO2 max before and after training. All 3 patients under already instituted and current therapy increased their walking distance and 2 of them their VO2 max after training. This indicates a possible additional benefit in individual cases.

[Long-term breathing via tracheostoma]

PATIENTS AND METHODS

From 1988 to 2/1997 we had introduced intermittent positive pressure ventilation (IPPV) in 298 patients. In most cases non-invasive nasal mask ventilation was possible, in 21 patients (7%) a tracheostoma was necessary. These 21 patients were analysed retrospectively due to age, sex, diagnose, ventilation mode, course of illness, home care and costs.

RESULTS

We had 13 male and 8 female patients, aged 49 years on average (min. 2, max. 84). 90% had neuromuscular diseases especially muscle dystrophies. Ventilation therapy was performed volume controlled with the cannula unblocked during daytime and blocked at night. Eighteen patients had industrial cannulas (72% Shiley, 28% Rüsch), 3 patients used silver cannulas. Daily ventilation amounted 24 hours in 7 patients, 6 to 14 hours in 14 patients. During the observed time 7 patients remained in stable health situation, in 9 patients the underlying disease was progressive and 5 of them died. IPPV was performed 50.7 months on an average, in living patients 68.8 months, in died 7.6 months. Fifteen patients lived at home, 5 were cared in nursing home, 1 patient stayed in hospital. Outside the hospital the bigger part of costs was paid by sick funds and care funds, the smaller part by social welfare offices. Often costs were divided. Total costs for caring about 24 hours ventilated patient at home amounted up to 21,000 German marks each month.

[Diaphragm pacing in chronic hypoventilation]

BACKGROUND

Diaphragm pacing in patients with intact phrenic nerve and diaphragm can be used as an alternative to mechanical ventilation. Indications cover diseases caused by central hypoventilation like C2-quadriplegia and Ondine's syndrome. Advantages are physiological ventilation with negative pressure and an improvement in articulation.

CASE REPORT

We report our experiences with a patient suffering from chronic hypoventilation caused by a ventilatory pump failure following tetraparesis due to congenital toxoplasmosis.

[Exercise tolerance of patients under nasal intermittent positive pressure ventilation (nIPPV)]

BACKGROUND

There are only a few papers concerning with exercise tolerance of patients under nasal intermittent positive pressure ventilation (nIPPV).

PATIENTS AND METHOD

Therefore since 1996 we routinely checked exercise tolerance of our nIPPV-patients when admitted to the hospital. Till March 1997 we had carried out 1386-minute walking tests (6-min WT) in 111 patients.

QUESTIONS

Is there an improvement of exercise tolerance in the course of nIPPV-therapy? Are hypoxemia or hypercapnia occurring during exercise-test?

METHODS

The 6-min WT was performed after one practice walk. The patients got oxygen in case of a preexisting oxygen therapy or in case of an oxygen saturation below 85% before starting. Blood gas analyses were carried out before and after stopping the test. Oxygen saturation and heart rate were registered continuously. The distance walked was measured. Twenty-one patients were tested before introducing nIPPV therapy and 3 months after home mechanical ventilation (HMV).

RESULTS

The average distance walked amounted only 283 +/- 82 m (norm in healthy persons: 800 m). pO2 decreased from 69 +/- 11 to 58 +/- 12 mm Hg, pCO2 increased from 47 +/- 8 to 49 +/- 8 mm Hg. Oxygen saturation (SaO2) fell from 92 +/- 5 to 80 +/- 10%, heart rate increased from 104 +/- 18 to 130 +/- 23 beats/min. The distance walked changed not significantly from 282 +/- 109 to 308 +/- 71 m. Six patients could be tested a 3rd time after 6 months HMV. The distance walked was 315 +/- 103 m (also no significant difference).

CONCLUSIONS

Everyday activity can cause severe hypoxemia in nIPPV patients. Ambulatory oxygen therapy should be considered in each case. A significant improvement of exercise tolerance under nIPPV therapy is not yet proven. Our data only show a tendency towards an increase.

[Noninvasive intermittent self-ventilation as a palliative measure in amyotrophic lateral sclerosis]

Almost all patients with amyotrophic lateral sclerosis (ALS) experience symptoms of nocturnal hypoventilation during the course of the illness. These symptoms can develop years before death and may severely affect quality of life. Non-invasive intermittent home mechanical ventilation (HMV) via mask is a possible palliative measure for these symptoms, which is not often used in Germany. We report on our experience with HMV in 24 patients with ALS. Our data show a good palliative effect in 17 of 24 treated patients. Severe complications did not occur. The mean ventilation time at present is 14 months. Available options and their consequences need to be discussed in detail with patients and relatives before HMV is initiated.

Native pulmonary muscular proliferation

Four cases with native pulmonary muscular proliferation (NPMP) are reported. The etiology of this rare condition is unknown. A hamartomatous process is discussed. In spite of its rarity the correct diagnosis of this condition is important. Both clinically and histologically in transbronchial biopsies, NPMP may be mistaken for pulmonary lymphangioleiomyomatosis (PLAM). Distinction of these 2 conditions is adamant, as PLAM has a poor prognosis, and, moreover may be associated with general disease, as with tuberous sclerosis. Whereas the typical distribution of more mature desmin positive muscle cells in a dense center core and more immature desmin negative radiating peripheral muscle cell proliferation with fascicular pattern in NPMP may be recognized in open lung biopsy, these differences may not become evident in small transbronchial biopsies. Immunohistochemical methods play an important role in the differential diagnosis--as with PLAM estrogen and progesterone receptors may be expressed and, most importantly, the reaction of the HMB45-antibody appears consistently positive in muscle cells of PLAM, while negative with NPMP. Thus, recognition of this clinically innocent disease is also possible in small tissue particles.

Effectiveness of radical systematic mediastinal lymphadenectomy in patients with resectable non-small cell lung cancer: results of a prospective randomized trial

OBJECTIVE

To evaluate the effectiveness of lymphadenectomy in the treatment of non-small cell lung cancer (NSCLC).

SUMMARY BACKGROUND DATA

The extent of lymphadenectomy in the treatment of NSCLC is still a matter of controversy. Although some centers perform mediastinal lymph node sampling (LS) with resection of only suspicious lymph nodes, others recommend a radical, systematic mediastinal lymphadenectomy (LA) to improve survival and to achieve a better staging.

METHODS

In a controlled, prospective, randomized clinical trial, the effects of LA on recurrence rates and survival were analyzed, comparing LS and LA in 169 patients with operable NSCLC.

RESULTS

After a median follow-up of 47 months, LA did not improve survival in the overall group of patients (hazard ratio: 0.78; 95% confidence interval: 0.47-1.24). Although recurrences rates tended to be reduced among patients who underwent LA, these decreases were not statistically significant (hazard ratio: 0.82; 95% confidence interval: 0.54-1.27). However, analysis of subgroups of patients according to histopathologic lymph node staging revealed that LA appears to prolong relapse-free survival (p = 0.037) with a borderline effect on overall survival (p = 0.058) in patients with limited lymph node involvement (pN1 disease or pN2 disease with involvement of only one lymph node level); in patients with pN0 disease, no survival benefit was observed.

CONCLUSIONS

Radical systematic mediastinal lymphadenectomy does not influence disease-free or overall survival in patients with NSCLC and without overt lymph node involvement. However, a small subgroup of patients with limited mediastinal lymph node metastases might benefit from a systematic lymphadenectomy.

[New therapy aspects of chronic respiratory insufficiency]

The therapy of chronic respiratory insufficiency has been extended in the last years. Additional to long-term oxygen therapy nasal CPAP-therapy and home mechanical ventilation have been introduced. The different kinds of therapy are the results of different pathophysiologic alterations in the different forms of chronic respiratory insufficiency. In parenchym diseases of the lung with hypoxemic respiratory insufficiency the hypoxemia is treated by increasing the inspiratory oxygen concentration. Ventilatory pump failures can be divided in 3 large groups: respiratory muscle fatigue, central alveolar hypoventilation and recidive pharyngeal obstruction during sleep. The therapeutic principles are relieving of the respiratory muscles by intermittent assisted or better controlled mechanical ventilation in muscle fatigue, securing the alveolar ventilation by controlled mechanical ventilation in central alveolar hypoventilation and pneumatic splinting of the pharyns by nasal CPAP in obstructive sleep apnoe.

[Noninvasive ventilation in acute respiratory insufficiency]

BACKGROUND AND AIM

Noninvasive positive pressure ventilation (NPPV) via face mask offers in comparison to endotracheal intubation in treating patients with acute respiratory failure (ARF) advantages like allowing swallowing and coughing. We report our experiences and try to verify the indications and the efficacy of NPPV.

PATIENTS AND METHODS

In the period of January 1991 until August 1996 109 patients (30 female, 79 male, mean age 61 +/- 12 years) received mechanical ventilation with NPPV representing 25% of all MVs in this term. As baseline capillary blood gases (CBG) were found: pH: 7.30 +/- 0, 10; pCO2: 64 +/- 19; pO2: 60 +/- 19 (all patients received supplemental oxygen). Success of NPPV was determined by an improvement of the baseline CBG.

RESULTS

NPPV was successful in 77 (71%) patients. Considering the kind of respiratory insufficiency the patient population was divided into 4 groups 1. acute hypoxemic respiratory failure, 2. acute hypercapnic ventilatory failure, 3. acute decompensation of chronic respiratory insufficiency (CRI) and 4. combined failure. Considering these subgroups we obtained the best results in the group of patients with hypercapnic disturbances. In patients with hypoxemic RF we observed a success of NPPV if the improvement of CBG occurred in the early stage (< or = 12 hours) of NPPV.

CONCLUSION

Our data indicate that application of NPPV is an effective and safe alternative to endotracheal intubation in many patients with hypercapnic ventilatory failure. NPPV is also successful in patients with hypoxemic RF with a milder course.

[6 minute walking test as stress test for patients treated by intermittent self-ventilation]

BACKGROUND

Until now there are no data about the exercise capacity of patients with chronic ventilatory pump failure before and during IPPV.

PATIENTS AND METHODS

55 patients with chronic ventilatory failure-20 patients before IPPV, 35 patients during mechanical ventilation with a mean of 16.5 months-were studied by the six-minute walking test. Eight patients were sampled in a follow-up study before and during IPPV with a mean of 2 months.

RESULTS

The median walking distance was reduced to 273 in. The exercise capacity of the follow-up patients was not improved. The arterial pO2 during exercise fell markedly, arterial pCO2 increased only moderate.

CONCLUSION

The exercise capacity of patients with chronic ventilatory failure is markedly reduced. Because of the significant oxygen desaturation on exercise we may frequently indicate ambulatory oxygen therapy.

[Patient-related rejection of nasal IPPV therapy. Patients, reasons, follow-up]

PATIENTS

We retrospectively analysed the course of 33 patients who had rejected nasal IPPV-therapy (1988 to February 1996).

RESULTS

The death-rate was higher (48%) compared to nasal IPPV patients in the same time (18%). The patients were divided in 3 main diagnostic groups (COPD, restrictive thoracic wall, neuromuscle disease). We observed the highest death-rate in COPD patients (66%) and the lowest death-rate in the group with scoliosis or chest wall disease (23%). This is the same result tendencially as in patients with nasal IPPV (mortality-rate COPD 66%, restrictive chest wall 6%).

[Noninvasive intermittent ventilation. A prospective data collection in patients with hypoventilation syndrome]

INTRODUCTION

Noninvasive intermittent ventilation is usually performed in patients with severe ventilatory pump disorder. From 1988 to 3/1995 we treated 163 patients with the aim of home mechanical ventilation (HMV).

PATIENTS AND RESULTS

In March 1993 115 of these 163 patients practiced HMV, 22 had already died and 26 had rejected or broken off ventilation therapy. The 115 patients were classified in three main diagnostic groups: Scoliosis or chest wall disease (n = 76), COPD (n = 11) and neuromuscular disease (n = 28). The mean pCO2 at rest of all patients before ventilation therapy was 56 (+/- 12) Torr and fell to 46 (+/- 5) Torr in the course of therapy. The maximum statical inspiration pressure PImax rose from average 3, 8 (+/- 2, 3) to 4, 9 (+/- 2, 0) kPa. There was a probability of surviving two years after onset of ventilation therapy of 85% in the scoliosis group, of 60% in the neuromuscular group and of 30% in the COPD group.

CONCLUSIONS

According to results of others home ventilation therapy was very successful in patients with chest wall disease. In some patients with neuromuscular disorder quality of life could be improved and life prolonged. Only half of the COPD patients could be treated successfully, whereas the other half had no benefit from noninvasive ventilation therapy.

[Perioperative use of noninvasive ventilation]

BACKGROUND AND AIM

Noninvasive mask ventilation is in some cases of respiratory failure the treatment of choice. It is used in cases of acute respiratory failure. We report about perioperative application of noninvasive mask ventilation.

PATIENTS AND METHODS

We treated 25 patients with respiratory failure pre- and/or postoperative with noninvasive mask ventilation.

RESULTS

The success rate in all patients was 68%, but it was very different in respect to the varying causes of respiratory failure.

CONCLUSION

With noninvasive mask ventilation it is possible to avoid in some patients with acute postoperative respiratory failure complications who are referred to intubation. In patients with postoperative decompensation of chronic respiratory failure postoperative treatment becomes easier, in extraordinary cases the method makes surgery possible.

Risk analysis and long-term survival in patients undergoing extended resection of locally advanced lung cancer

Although locally advanced lung cancer frequently necessitates extended resections to preserve a chance for cure, a higher morbidity is associated with extended resections. It is not known whether the increased morbidity is of relevance for the long-term outcome. It also remains unclear whether exclusion of certain patients according to their risk factors can diminish mortality in these patients. This study therefore investigated whether certain risk factors predispose patients undergoing extended pulmonary resections to increased morbidity or mortality. It also assessed the long-term survival. The cases of 126 consecutive patients with locally advanced lung cancer (stage T3 or T4) were prospectively documented. Seventy-five percent of the patients required an extended resection and 25% a nonextended resection. Extended resections were associated with a significantly increased overall morbidity (p < 0.002). However, mortality, severe complications, or multiple complications were not significantly increased after extended resections. No risk factor predisposed to an increased mortality. Risk factors that were associated with particular postoperative complications were pathologic ergonometry (p < 0.002), a positive cardiac score (p < 0.003), coronary artery disease (p = 0.021), and an increased pulmonary risk score (p < 0.05). Overall 3-year survival was 31%. Patients undergoing extended resections for stage T3 or T4 tumors with no residual tumor (70% of the patients) showed a 3-year survival of 33%. We conclude that postoperative mortality cannot be reduced by excluding patients on the basis of particular risk factors from operations that require extended resections. If a patient is considered to be eligible to undergo pulmonary resection, he or she can be considered to be eligible to undergo extended pulmonary resection. Because prognosis is dismal in nonresected locally advanced lung cancer, we recommend an aggressive surgical approach.

[Adenomatoid cystic lung abnormality in adults with associated bronchioloalveolar carcinoma]

Lung cysts were observed by chance in the chest radiographs from two women aged 20 and 41. In the surgical specimens the lesions proved to be congenital cystic adenomatoid malformation type 1. The cysts were partially lined by mucous cells. Also near the cysts there were circumscribed tubuloacinar proliferations of mucous cells. In both cases a transition into a bronchioloalveolar carcinoma was seen. Histochemically no sulphomucins could be demonstrated by means of an alcian blue pH 1 reaction in the tumor cells, but was demonstrated in the non-neoplastic cells of the malformation. In both cases CEA was demonstrated in the tumor cells. Some cells in the tubuloacinar proliferations were weakly CEA positive. In one patient the diagnosis of carcinoma was made by intraoperative frozen section and a lobectomy was performed. The other patient had first only a resection of her cystic lesions and had to be reoperated because of the results of the pathological examination. Both patients had no recurrence in the 8 years following the operation. In the literature we found 5 cases of congenital cystic adenomatoid malformation in adults. In 2 cases there was also an associated bronchioloalveolar carcinoma. Several reports exist on the association of different kinds of cystic lung lesions and malignant tumors and their possible pathogenetic relationship. In this paper we draw attention to the development of malignant neoplasia in congenital cystic adenomatoid malformation in adults and its diagnostic problems.

[Cardiac stroke volume and oxygen transport during volume controlled self-ventilation]

BACKGROUND AND AIM

In patients with ventilatory pump disorder cardiac decompensation can occur after introduction of nasal intermittent positive pressure ventilation therapy (nasal IPPV). Therefore we carried out hemodynamic measurements in eight patients.

PATIENTS AND METHODS

Before starting non-invasive ventilation and 1 hour later we measured pulmonary artery pressures, central venous pressures, pulmonary capillary wedge pressures and cardiac output. Blood gas analysis of arterial and mixed venous blood were carried out. We calculated oxygen delivery and oxygen extraction rate.

RESULTS

After 1 hour of ventilation cardiac output was reduced from 5.9 l/min to 4.1 l/min, oxygen delivery was reduced from 1002 ml/min to 771 ml/min. These results were significant. Three patients were measured hourly during a prolonged period of ventilation. After 4 to 6 hours cardiac output almost reached again the level before ventilation.

CONCLUSION

Similar to invasive ventilation or nCPAP-therapy non-invasive ventilation (nIPPV) causes a significant reduction of cardiac output 1 hour after starting ventilation. An adaptation of cardiac output could be reached after a couple of hours.

[Noninvasive self-ventilation--successful transition aid in the waiting period before lung transplantation?]

BACKGROUND

Non-invasive mechanical ventilation is used with success for ventilatory failure due to derangements of the respiratory pump. Efficacy in pulmonary diseases is controversial. Still non-invasive intermittent ventilation is reported as a mean of bridging the period till lung transplantation can be performed.

PATIENTS AND METHODS

We report of 20 patients from 5 centers who were treated with non-invasive intermittent ventilation while lung transplantation was planned.

RESULTS AND CONCLUSION

Non-invasive intermittent ventilation was seen as successful in 14 patients. Of these 4 are transplanted after up to 2 years, 4 are still waiting, 2 have not yet entered a lung transplantation program, 1 continued non-invasive intermittent ventilation after refusal to be enlisted, 3 meanwhile died. In the group of non-successful non-invasive intermittent ventilation 2 patients were transplanted after a short waiting period. All remaining 4 patients died. It seems that non-invasive intermittent ventilation may be helpful in prolonging the period of survival while waiting for lung transplantation.