Chronic Ventilatory Insufficiency Research Articles

Limits and Ethics of Mechanical Ventilation and Intensive Care Medicine in Old Age

Changing demography with more older people and more patients with chronic diseases as well as the progress of medicine leads to more geriatric patients treated in intensive care and requiring mechanical ventilation due to severe respiratory insufficiency.Frailty is associated with a more complicated intensive care stay, more difficult convalescence and with a higher mortality.In principle, geriatric expertise should be brought in as early as possible in the course of intensive care treatment for older patients in order to carry out adequate risk stratification and, depending on the extent of the impairment, to plan discharge or early rehabilitation.In older and frail patients preexisting chronic ventilatory insufficiency often leads to prolonged weaning. Patients with weaning failure should be referred to a specialized weaning center. Part of the assessment will be whether out-of-hospital invasive or non invasive ventilation is indicated and the wish of the patient.In intensive care the likelihood of a successful outcome and the patient's wishes must constantly be re-evaluated. This is particularly true in older patients. In addition it should be clarified with the patients and relatives what constitutes "success"; for example a patient may consider intensive care "worth it" if the ultimate goal is discharge to their own home but not if nursing home care and tracheostomy ventilation is the best that can be achieved. It may become apparent that a successful outcome is unlikely and then withdrawal of invasive ventilation is appropriate.

Efficacy of new intermittent abdominal pressure ventilator for post-ischemic cervical myelopathy ventilatory insufficiency

Non-invasive ventilation (NIV) is the treatment of choice for patients symptomatic for respiratory muscle dysfunction. It can normalize gas exchange and provide up to continuous non-invasive ventilator support (CNVS) as an alternative to intubation and tracheotomy. It is usually provided via non-invasive facial interfaces or mouthpieces, but these can be uncomfortable and uncosmetic. The intermittent abdominal pressure ventilator (IAPV) has been used for diurnal ventilatory support since 1938 but has been off the market since about 1990. Now, however, with greater emphasis on non-invasive management, a new IAPV is available. A patient with chronic ventilatory insufficiency post-ischemic cervical myelopathy, dependent on sleep NVS since 2003, developed symptomatic daytime hypercapnia for which he also used diurnal NVS via nasal pillows. However, he preferred not having to use facial interfaces. When not using diurnal NVS he was becoming dyspnoeic. Diurnal use of an IAPV was introduced. Arterial blood gas analysis using the IAPV decreased his blood pH from 7.45 to 7.42, PaCO2 from 58 to 37 mmHg, and improved PaO2 from 62 to 92 mmHg. At discharge, the patient used the IAPV 8 h/day with improved mood and quality of life. Consequently, he returned to work as a painter.

Efficacy of new intermittent abdominal pressure ventilator for post-ischemic cervical myelopathy ventilatory insufficiency

Non-invasive ventilation (NIV) is the treatment of choice for patients symptomatic for respiratory muscle dysfunction. It can normalize gas exchange and provide up to continuous non-invasive ventilator support (CNVS) as an alternative to intubation and tracheotomy. It is usually provided via non-invasive facial interfaces or mouthpieces, but these can be uncomfortable and uncosmetic. The intermittent abdominal pressure ventilator (IAPV) has been used for diurnal ventilatory support since 1938 but has been off the market since about 1990. Now, however, with greater emphasis on non-invasive management, a new IAPV is available. A patient with chronic ventilatory insufficiency post-ischemic cervical myelopathy, dependent on sleep NVS since 2003, developed symptomatic daytime hypercapnia for which he also used diurnal NVS via nasal pillows. However, he preferred not having to use facial interfaces. When not using diurnal NVS he was becoming dyspnoeic. Diurnal use of an IAPV was introduced. Arterial blood gas analysis using the IAPV decreased his blood pH from 7.45 to 7.42, PaCO2 from 58 to 37mmHg, and improved PaO2 from 62 to 92mmHg. At discharge, the patient used the IAPV 8 h/day with improved mood and quality of life. Consequently, he returned to work as a painter.

WeanNet: The network of weaning units of the DGP (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin) - results to epidemiology an outcome in patients with prolonged weaning

In 40 % of all ventilated patients weaning is problematic. Prolonged weaning is associated with an increased mortality. For the first time, data on epidemiology and outcomes of 6899 patients with prolonged weaning from the WeanNet register are published in this study. Patients with prolonged weaning suffer from profound comorbidities (median 5 relevant comorbidities). The majority of patients (62.2 %) were successfully weaned from the ventilator and dischared from the weaning unit without invasive ventialtion after a median of 33 days. Caused by chronic ventilatory insufficiency after prolonged weaning, non-invasive ventilation (NIV) was initiated in 19.4% of patients. The patients who were discharged with NIV were significantly younger than the average (68 vs. 71 years).In 22.9 % of the patients weaning definitively failed and continuous invasive ventilation was needed. Compared to other main reasons for mechanical ventilation patients with chronic obstructive pulmonary disease (COPD) were rarely completely weaned from the respirator and more often needed NIV for home mechanical ventilation. In total 14,9 % of the 6899 patients died during the treatment in the weaning unit. WeanNet is very important in the care of patients with prolonged weaning.

ABSTRACT 406

Background and aims: The main indications for tracheotomy in children generally are long-term cardiorespiratory compromise resulting from chronic ventilatory insufficiency or the presence of an upper airway obstruction. Aims: The aim of this study was to evaluate indications, complications and prognosis for tracheotomies at a tertiary care pediatric intensive care unit, Eskisehir, Turkey, between 2011-December 2013. Methods: A retrospective evaluation of medical records have been performed. Results: 948 children have been hospitalized in our PICU, 24 children have tracheotomy. Eight children excluded because of that have been referred to our hospital with tracheotomy. 16 tracheotomies were performed in our PICU (16/948;1.7%) and the most common indication is prolonged intubation/preparedness for home ventilation, mainly neuromuscular disorders. Three children requires tracheotomy because of they have upper airway obstruction. Median length of intubation before tracheotomy procedure was 57 days and median length of PICU stay after tracheotomy procedure was 59 days. Major cause of delayed tracheotomy was unwillingness of the parents for this procedure. None of these patients have early post-operative complications. Eight out of these 16 children died, none of these children have tracheotomy-related complications. 6 children have been discharged with oxygen support/home ventilation, and two children have been discharged with room air oxygen. Conclusions: Tracheotomies performed in our PICU during three years period were associated with low-incidence of procedure related morbidity and mortality. Willingness of the parents for tracheotomy and education of parents for home ventilation or other respiratory support at home are major indicators for the length of intubation and length of hospital stay as well as underlying disease of children.

Ondine’s Curse with Accompanying Trigeminal and Glossopharyngeal Neuralgia Secondary to Medullary Telangiectasia

Central hypoventilation syndrome ("Ondine's Curse") is an infrequent disorder that can lead to serious acute or chronic health consequences. This syndrome, especially in adults, is rare, and even less frequent in the absence of clear pathogenic lesions on MRI. In addition, we are not aware of any previously reported cases with associated cranial nerve neuralgias. We describe a patient with baseline trigeminal and glossopharyngeal neuralgia, admitted with episodes of severe hypoventilatory failure of central origin, consistent with "Ondine's Curse". After evaluation, she was found to have a medullary capillary telangiectasia, thought to be the causative lesion, and which could explain her complete neurologic and hypoventilatory syndrome. The patient was treated with placement of a diaphragmatic pacing system, which has been effective thus far. This case illustrates the need for investigation of centrally mediated apnea, especially when co-occurring cranial nerve neuralgia is present and cardiopulmonary evaluation is negative. It provides an example of capillary telangiectasia as the causative lesion, one that to our knowledge has not been reported before. Placement of a diaphragmatic pacing system was warranted and became lifesaving as the patient was deemed to be severely incapacitated by chronic ventilatory insufficiency.

Successful treatment of secondary pulmonary hypertension by long-term non-invasive positive pressure ventilation

The case of 57-year-old man with chronic ventilatory insufficiency due to asbestos pleurisy and sequelae of pulmonary tuberculosis is described. Non-invasive positive pressure ventilation therapy appeared to improve the pulmonary hypertension. Ultrasonic cardiography was valuable in the serial assessment of pulmonary artery pressure.

Management

Non-invasive ventilation (NIV) provides significant advantages to the paediatrician who cares for children with chronic ventilatory insufficiency and who would like to manage these children in the home environment. There is a growing experience in the use of NIV in the management of children with upper airway obstruction, ventilatory failure due to weakness or distortion of the thoracic cage and in children with abnormalities to their central respiratory drive especially during sleep. Success hinges on choosing the correct patient and the most appropriate device with a team approach to both the early assessment and follow-up. It may not be successful on the first attempt and often a phased introduction and some perseverance is required on the part of the paediatric team and the family. Home ventilation is possible, practical and advantageous compared with institutional living and non-invasive techniques can assist the paediatrician in achieving this goal.

Lung and chest wall mechanics in ventilated patients with end stage idiopathic pulmonary fibrosis

BACKGROUNDIdiopathic pulmonary fibrosis is an inflammatory disease which leads to chronic ventilatory insufficiency and is characterised by a reduction in pulmonary static and dynamic volumes. It has been suggested that...

Clinical implications of maximal respiratory pressure determinations for individuals with Duchenne muscular dystrophy.

To analyze the relationship between disease progression, pulmonary volumes, respiratory muscle strength (maximum inspiratory [MIP] and expiratory [MEP] pressure), and arterial blood gases for patients with Duchenne muscular dystrophy (DMD). An inception cohort study of pulmonary volumes, MIPs, and MEPs, correlated with age and PaCO2 levels and with each other using linear and nonlinear regression analyses. Outpatient clinic. Fifty-two consecutive DMD patients who presented for regular evaluations at a regional DMD center. Maximum expiratory pressures were 47.7% +/- 10.9% of normal in the 167- to 14-year-old patients and decreased linearly thereafter (MEP% = -2.7 x age +73.8; p < .001). Declines in MEP also correlated linearly with expiratory reserve volume (p < .001) and inversely with residual volume (p < .001). By contrast, MIP was 66.3% +/- 19.0% in the 357- to 14-year-old patients and then declined to 30.2% +/- 19.5% after age 14. No linear relationships were found with age but declines did correlate linearly with inspiratory reserve volume (p < .001) and total lung capacity (p < .001). PaCO2 elevations correlated best with decreases in MIP (p < .0001) and appeared when MIP was below 30cmH2O. Lung volume changes in DMD patients correlate with respiratory muscle weakness, and although inspiratory muscle dysfunction plays a key role in the development of chronic ventilatory insufficiency, reductions in expiratory muscle strength are the first signs of dysfunction and lead to the first episodes of respiratory failure.

Noninvasive long-term ventilatory support for individuals with spinal muscular atrophy and functional bulbar musculature

Ten individuals with spinal muscular atrophy (SMA) and chronic ventilatory insufficiency were trained in the use of assisted coughing techniques and received intermittent positive pressure ventilation (IPPV) via oral and/ or nasal interfaces for a mean of 5.3 (range = 1 to 17) years. During this time they had significantly fewer respiratory complications than before introduction of noninvasive respiratory muscle aids despite the fact that 6 of the 10 went on to require more than 20 hours per day of ventilator use with less than 2 hours of ventilator-free breathing time (VFBT). All except two noninvasive IPPV users had vital capacities (VCs) less than 13% of predicted normal. They could, however, communicate verbally and take nutrition by mouth. All of the patients remained in the community. Five patients were gainfully employed and four were in school. We conclude that noninvasive respiratory muscle aids including noninvasive IPPV and assisted coughing techniques are effective and practical alternatives to tracheostomy for SMA patients with ventilatory failure but functional bulbar musculature.

Nasal Positive Pressure Ventilation in Patients with Acute Respiratory Failure: Difficult and Time-Consuming Procedure for Nurses

Intubation and mechanical ventilation are well-established techniques in the management of patients with acute respiratory failure; however, there are situations in which these procedures cannot be used safely for various reasons. A recently described noninvasive technique, nasal positive-pressure ventilation (NPPV), has been developed for home ventilation of certain patients with chronic ventilatory insufficiency. We hypothesized that NPPV could be used in selected patients in whom intubation and mechanical ventilation were clearly indicated, but not immediately possible, or even contraindicated. Six patients were treated with NPPV during an episode of acute respiratory failure and enrolled in a prospective study. We found that NPPV was successful in avoiding intubation, but only in the three patients suffering from a restrictive pulmonary disorder, whereas the procedure was unsuccessful in patients with obstructive disorders. Moreover, in every patient, acute NPPV was very time-consuming for the nursing staff: in patients with restrictive disorders, a nurse had to monitor a patient submitted to NPPV during 41 ± 9 percent of the duration of ventilation and during 91 ± 9 percent of the NPPV time in patients with obstructive disorders. We conclude that acute NPPV may be attempted in selected patients with acute respiratory failure, predominantly patients with restrictive respiratory disorders, but that this procedure is very time-consuming for nurses. Intubation and mechanical ventilation are well-established techniques in the management of patients with acute respiratory failure; however, there are situations in which these procedures cannot be used safely for various reasons. A recently described noninvasive technique, nasal positive-pressure ventilation (NPPV), has been developed for home ventilation of certain patients with chronic ventilatory insufficiency. We hypothesized that NPPV could be used in selected patients in whom intubation and mechanical ventilation were clearly indicated, but not immediately possible, or even contraindicated. Six patients were treated with NPPV during an episode of acute respiratory failure and enrolled in a prospective study. We found that NPPV was successful in avoiding intubation, but only in the three patients suffering from a restrictive pulmonary disorder, whereas the procedure was unsuccessful in patients with obstructive disorders. Moreover, in every patient, acute NPPV was very time-consuming for the nursing staff: in patients with restrictive disorders, a nurse had to monitor a patient submitted to NPPV during 41 ± 9 percent of the duration of ventilation and during 91 ± 9 percent of the NPPV time in patients with obstructive disorders. We conclude that acute NPPV may be attempted in selected patients with acute respiratory failure, predominantly patients with restrictive respiratory disorders, but that this procedure is very time-consuming for nurses.

Fundamental Considerations in Pacing of the Diaphragm for Chronic Ventilatory Insufficiency: A Multi‐Center Study

Records were reviewed of 477 patients who had diaphragm pacemakers implanted for treatment of chronic hypoventilation. Three groups were established for comparison. (1) Center group: 165 patients operated on in six medical centers participating in a cooperative study; (2) Noncenter group, sufficient data available: 203 patients operated on by surgeons with experience limited to a few cases; (3) Nonstudy group, minimal data available: 109 patients operated on as in group 2; vital statistics only were contributed. The protocol for data gathering was comprised of 154 major variables. Basic data on age, sex, diagnosis and etiology were analyzed for homogenicity of data among the groups. A comprehensive analysis of the pacing methods, complication and results from the Center group yielded information on the early experience with diaphragm pacing important to its future application.

Management of Chronic Ventilatory Insufficiency with Electrical Diaphragm Pacing

We have had experience with diaphragm pacing in 24 patients at the Toronto Western Hospital. Fourteen patients have undergone bilateral implants to treat chronic ventilatory insufficiency (CVI) caused by traumatic tetraplegia at the C1/2 level (eight patients), neurogenic apnea (five) and one case of neonatal apnea. Unilateral stimulators for nocturnal pacing have been implanted in five patients with central alveolar hypoventilation (sleep apnea) and five patients who suffered CVI resulting from various etiologies. Of the patients who were ventilatory dependent, 80% were successfully weaned and in the entire series, 58% of the patients are living. Diaphragm pacing was successful in 67%, partially successful in 8% and ineffective in 25%. The major complications were: death by pneumonia, failure of the radio receivers, and infection. Diaphragm pacing is the treatment of choice for patients who are ventilator dependent and tetraplegic from upper cervical trauma or in some cases of neurogenic apnea; it may be life saving for patients who suffer central alveolar hypoventilation.

Response of the diaphragm muscle to electrical stimulation of the phrenic nerve

The histological, histochemical, and ultrastructural features of canine diaphragms subjected to pacing by high-frequency electrical stimulation (27 to 33 Hz) of the phrenic nerve are compared with unstimulated diaphragms and with diaphragms subjected to pacing by low-frequency stimulation (11 to 13 Hz). The high-frequency group showed a reduced tidal volume (fatigue) after long-term stimulation, and myopathic changes which included enlarged internal and sarcolemmal nuclei, ring fibers, moth-eaten fibers with irregular histochemical staining, core/targetoid fibers, and smearing and aggregation of Z-band material with electron microscopy. The low-frequency group did not develop a significant degree of fatigue or pathological changes, and showed histochemical evidence of transformation to fast-twitch (type II) fibers. Possible pathogenic mechanisms and their similarity to those in certain human neuromuscular diseases are discussed. The application of the findings resulting from high- and low-frequency stimulation to long-term diaphragm pacing in humans with chronic ventilatory insufficiency is also discussed.

Diaphragm pacing: Histopathological changes in the phrenic nerve following long-term electrical stimulation

Phrenic nerves were obtained at autopsy from 7 patients with chronic ventilatory insufficiency. One or both nerves had been subjected to electrical stimulation to pace the diaphragm for about 2 months to 4 years. Sections of the nerves made from above, at the level of, and below the site of application of the cuff electrode were studied microscopically. In most specimens, focal areas of demyelination were seen ranging from severity from swelling and fragmentation of isolated fibers to focal myelin destruction with phagocytic activity and total removal of myelin with fibrosis. Some axone loss was seen. The fact that the nerves from 2 patients, each stimulated for about 2 years, showed no changes suggests that injury to the nerve was not caused by the electrical stimuli but rather was secondary to the technique of application and fixation of the cuff electrode to the nerve.

Diaphragm pacing by radiofrequency transmission in the treatment of chronic ventilatory insufficiency: Present status: W. W. L. Glenn, W. G. Holcomb, J. Hogan, I. Matano, J. B. L. Gee, E. K. Motoyama, C. S. Kim, R. S. Poirier, and G. Forbes. J. Thorac. Cardiovasc. Surg. 66:505–520 (October), 1973

Diaphragm pacing by radiofrequency transmission in the treatment of chronic ventilatory insufficiency: Present status: W. W. L. Glenn, W. G. Holcomb, J. Hogan, I. Matano, J. B. L. Gee, E. K. Motoyama, C. S. Kim, R. S. Poirier, and G. Forbes. J. Thorac. Cardiovasc. Surg. 66:505–520 (October), 1973

Diaphragm pacing by radiofrequency transmission in the treatment of chronic ventilatory insufficiency: Present status

Diaphragm pacing by radiofrequency transmission in the treatment of chronic ventilatory insufficiency: Present status