Showing papers on "Hypoventilation published in 1991"
Journal Article•
TL;DR: It is concluded that children with Down syndrome frequently in have OSAS, with OSA, hypoxemia, and hypoventilation, and it is speculated that OSAS may contribute to the unexplained pulmonary hypertension seen in children with down syndrome.
Abstract: Children with Down syndrome have many predisposing factors for the obstructive sleep apnea syndrome (OSAS), yet the type and severity of OSAS in this population has not been characterized. Fifty-three subjects with Down syndrome (mean age 7.4 +/- 1.2 [SE] years; range 2 weeks to 51 years) were studied. Chest wall movement, heart rate, electroculogram, end-tidal PO2 and PCO2, transcutaneous PO2 and PCO2, and arterial oxygen saturation were measured during a daytime nap polysomnogram. Sixteen of these children also underwent overnight polysomnography. Nap polysomnograms were abnormal in 77% of children; 45% had obstructive sleep apnea (OSA), 4% had central apnea, and 6% had mixed apneas; 66% had hypoventilation (end-tidal PCO2 greater than 45 mm Hg) and 32% desaturation (arterial oxygen saturation less than 90%). Overnight studies were abnormal in 100% of children, with OSA in 63%, hypoventilation in 81%, and desaturation in 56%. Nap studies significantly underestimated the presence of abnormalities when compared to overnight polysomnograms. Seventeen (32%) of the children were referred for testing because OSAS was clinically suspected, but there was no clinical suspicion of OSAS in 36 (68%) children. Neither age, obesity, nor the presence of congenital heart disease affected the incidence of OSA, desaturation, or hypoventilation. Polysomnograms improved in all 8 children who underwent tonsillectomy and adenoidectomy, but they normalized in only 3. It is concluded that children with Down syndrome frequently in have OSAS, with OSA, hypoxemia, and hypoventilation. Obstructive sleep apnea syndrome is seen frequently in those children in whom it is not clinically suspected. It is speculated that OSAS may contribute to the unexplained pulmonary hypertension seen in children with Down syndrome.
398 citations
TL;DR: The findings indicate that FMMV is a viable option for short-term (one to four days) ventilatory support of patients with hypercapnic respiratory failure and insufficiency.
309 citations
01 Jul 1991
TL;DR: Routine pulmonary function tests may be useful for screening for reductions in nocturnal oxygen saturation and also may have prognostic value, according to the results of spirometry, which was compared with several formal polysomnographic variables.
Abstract: Breathing abnormalities and nocturnal hypoventilation occur in patients with amyotrophic lateral sclerosis (ALS). A prospective study was undertaken to determine the relationship of pulmonary function test abnormalities with quality of sleep and survival in 21 patients with ALS. Results of spirometry including determination of maximal respiratory pressures and arterial blood gases were compared with several formal polysomnographic variables and then also with 18-month survival. The patients had mild to moderate pulmonary function deficits, but the quality of sleep was best related to age (mean age, 58.5 years). The results of pulmonary function tests and arterial blood gas measurements did not correlate well with the presence of nocturnal breathing events or survival time, but the maximal inspiratory pressure was 86% sensitive for predicting the presence of a nocturnal oxygen saturation nadir of 80% or less and 100% sensitive for predicting 18-month survival. Although obstructive breathing events occurred, the primary explanation for the decline in nocturnal oxygen saturation was hypoventilation. We conclude that routine pulmonary function tests may be useful for screening for reductions in nocturnal oxygen saturation and also may have prognostic value. Further studies may determine whether treatment of nocturnal hypoventilation will have an effect on survival in patients with ALS who have breathing impairment.
119 citations
TL;DR: The scans showed segmental areas of increased radionuclide uptake in ribs, indicative of bone infarction, and a possible sequence of events is that the rib infarcts are primary and cause bone pain, followed by soft tissue reaction, pleuritis, and splinting.
73 citations
TL;DR: Voluntary hyperventilation studies herein suggest a predominant role for impairment of ventilatory control in the maintenance of hypercapnia in OSA since a fall of PaCO2 into the normal range can usually be obtained.
72 citations
01 Nov 1991
TL;DR: The Prader-Willi syndrome is characterized by infantile hypotonia, early childhood obesity, mental deficiency, short stature, small hands and feet, and hypogonadism; many patients also have hypersomnolence and daytime hypoxemia.
Abstract: The Prader-Willi syndrome is characterized by infantile hypotonia, early childhood obesity, mental deficiency, short stature, small hands and feet, and hypogonadism. Many patients also have hypersomnolence, experience daytime hypoventilation, and subsequently die prematurely of cardiorespiratory failure. Hypersomnolence and daytime hypoventilation are also common occurrences in the sleep apnea syndrome. For a better understanding of the relationship of sleep to the features of the Prader-Willi syndrome, we retrospectively reviewed five patients (two adults, one adolescent, and two children) with this syndrome who underwent polysomnography. All patients were obese; they had hypersomnolence and daytime hypoxemia, and they snored. In all patients, the apnea plus hypopnea index was less than 10 episodes per hour of sleep. During rapid eye movement sleep, nonapneic reductions in oxyhemoglobin saturation were detected in one adult and in one child. Despite the presence of morbid obesity and a history of snoring, patients with Prader-Willi syndrome seem to have only mild sleep-disordered breathing.
55 citations
TL;DR: It is concluded that a degree of controlled “hypoventilation” by deliberately choosing Paw < 45 cmH2O can be successfully used to ventilate children with severe status asthmaticus with a reduced rate of pressure‐related complications.
Abstract: We have conducted a retrospective survey of 79 children out of a total hospital asthmatic patient population of 2,412, admitted over a 32 month period to the ICU for the management of severe status asthmaticus. All patients were in severe respiratory distress with CO2 retention; 19 required mechanical ventilation due to increasing fatigue and worsening bronchospasm, having failed to respond to either inhaled or IV bronchodilator therapy. All patients were ventilated at slow rates (less than 12 min) and their airway pressure (Paw) was deliberately kept below 45 cmH2O, while accepting a PaCO2 in the 45-60 mmHg range, as long as the pH was compensated. Although two patients developed pneumothoraces while on positive pressure ventilation, these were resolved without incidents. Five patients who had mediastinal or subcutaneous air leaks prior to intubation did not develop pneumothoraces. Following the initiation of mechanical ventilation, IV beta-agonist therapy was increased in order to reverse the bronchospasm and reduce the duration of mechanical ventilation. Mean duration of intubation was 42 hours. Fourteen of the 19 patients were weaned and extubated within 48 hours. All patients survived without sequelae. We conclude that a degree of controlled "hypoventilation" by deliberately choosing Paw less than 45 cmH2O can be successfully used to ventilate children with severe status asthmaticus with a reduced rate of pressure-related complications.
52 citations
TL;DR: Moebius syndrome is described in an infant with central hypoventilation and brainstem calcification and limb defects and bilateral paralysis of the 6th, 7th, 9th, 10th, and 12th cranial nerves.
Abstract: Moebius syndrome (MS) is described in an infant with central hypoventilation and brainstem calcification. The patient had limb defects and bilateral paralysis of the 6th, 7th, 9th, 10th, and 12th cranial nerves. Mechanical ventilation was continued from birth because of shallow spontaneous respiration. Computed tomography revealed brainstem atrophy and four small calcifications restricted to the dorsal portion of the pons and medulla. Prenatal brainstem injury such as ischaemia may have caused MS and central hypoventilation.
33 citations
TL;DR: Pulmonary distention was mainly influenced by upper airway obstruction score, while patients with chronic obstructive pulmonary disease (COPD) did not suffer from gas trapping, and hypercapnia occurred in both upper and lowerAirway obstruction, while hypoxemia was principally observed in COPD patients.
Abstract: High-frequency jet ventilation has been reported as an effective method of ventilation during laryngoscopy, but may expose the patient to the risks of barotrauma or alveolar hypoventilation. The aim of the study was to evaluate the determining factors of pulmonary complications under high-frequency jet ventilation in 83 patients undergoing laryngoscopy for upper airway cancer. Pulmonary distention was mainly influenced by upper airway obstruction score (p = .0001), while patients with chronic obstructive pulmonary disease (COPD) did not suffer from gas trapping. Impaired gas exchange was predicted by increased weight (p = .0001), smaller injector diameter (p = .02), and lower airway obstruction (p = .001). Hypercapnia occurred in both upper and lower airway obstruction, while hypoxemia was principally observed in COPD patients. Emphasis is placed on monitoring by pulse oximetry, end-expiratory pressure, and PCO2 measurement, especially in patients with obesity, COPD, or upper airway obstruction.
28 citations
Journal Article•
TL;DR: A 28-yr-old black man with sickle cell anemia who presented with severe chest pain secondary to acute infarction of the body of the sternum, hypoventilation, and hypoxemia with no evidence of acute chest syndrome is described.
Abstract: This article describes a 28-yr-old black man with sickle cell anemia who presented with severe chest pain secondary to acute infarction of the body of the sternum, hypoventilation, and hypoxemia with no evidence of acute chest syndrome. A bone scan performed 5 days after admission revealed increased uptake in the sternum, suggesting sternal infarction. Repeat bone scan performed 2 mo later demonstrated normal concentration in the sternum.
26 citations
TL;DR: Evaluated the frequency of adverse respiratory effects after ketamine sedation in children and young adults during cardiac catheterization and reported side effects include numbness, nystagmus, diplopia, apathy, vivid dreams and hallucinations.
Abstract: Ketamine is a phencyclidine derivative which is used for its anesthetic, analgesic and amnestic qualities. Ketamine's reported side effects include respiratory depression, which may range from mild hypoventilation to prolonged central apnea; cardiovascular changes that include increased systemic and pulmonary vascular resistance; and postanesthetic emergent reactions, which include numbness, nystagmus, diplopia, apathy, vivid dreams and hallucinations.1,2 This report evaluates the frequency of adverse respiratory effects after ketamine sedation in children and young adults during cardiac catheterization.
TL;DR: PEEP does not seem to be effective in preventing venous air embolism, and moderate hypoventilation is recommended during the most critical period of exposing the posterior fossa followed by normoventilated when surgery of the actual lesion has begun.
Abstract: The effect of ventilation (normo-, hypo-, and hyperventilation) on transverse sinus pressure (TSP), central venous pressure (CVP), mean arterial blood pressure (mABP), and heart rate was studied in 15 patients undergoing neurosurgical treatment in the sitting position for tumors of the posterior fossa, and the findings were compared with the influence of positive end expiratory pressure (PEEP) on these parameters. TSP was not influenced significantly by PEEP ranging from 0 to 15 mbar, whereas CVP increased. At the same time, mABP decreased slightly. In contrast, TSP showed characteristic changes with varying ventilation: during normoventilation [end expiratory CO2 pressure (PECO2), 38 mm Hg], TSP was 3 mm Hg and increased to 7 mm Hg on average with hypoventilation (PECO2, 44 mm Hg), whereas hyperventilation (PECO2, 32 mm Hg) caused a reduction in TSP to the atmospheric range. At the same time, CVP remained unchanged, whereas mABP increased with hypoventilation. Presuming that the risk of venous air embolism is closely related to the level of TSP, our results allow the following conclusions. 1) PEEP does not seem to be effective in preventing venous air embolism. 2) Hyperventilation is dangerous in the sitting position, as TSP is reduced to the atmospheric and even subatmospheric range. 3) To prevent air embolism, moderate hypoventilation is recommended during the most critical period of exposing the posterior fossa followed by normoventilation when surgery of the actual lesion has begun.
TL;DR: Four patients with ophthalmoplegia plus showed pathological sleep-related breathing patterns consisting of sleep apneic polygraphic tracings mainly of the central type or of REM-related hypoventilation episodes, which are suggested to have a central origin and be related to the underlying metabolic disturbance.
Abstract: Nocturnal polygraphic recordings (electroencephalography, electro-oculography, submental and intercostal muscle electromyography, electrocardiography, respiration by thoracic strain gauges and oronasal thermistors) with continuous monitoring of arterial oxyhemoglobin saturation by pulse oximeter were performed in 8 patients with ophthalmoplegia plus. All patients except 1 had normal blood gas values and normal lung volumes associated with a diminished ventilatory response to inhaled CO2 during wakefulness. Four patients showed pathological sleep-related breathing patterns consisting of sleep apneic polygraphic tracings mainly of the central type or of REM-related hypoventilation episodes. It is suggested that these disorders in patients with ophthalmoplegia plus may have a central origin and be related to the underlying metabolic disturbance.
TL;DR: This discussion presented the most common causes of postoperative pulmonary complications, using the categories of obstruction, hypoxemia, and hypoventilation for structure to identify problems and patients at risk for these problems.
Journal Article•
TL;DR: Status asthmaticus is a medical emergency that requires careful evaluation and aggressive therapy, and nonconventional therapies should be considered only if conventional treatment fails.
Abstract: Status asthmaticus is a medical emergency that requires careful evaluation and aggressive therapy. The mainstay of medical therapy is frequent administration of beta-agonist inhalations, combined with early corticosteroid use. Intravenous magnesium can be used as an adjunctive measure. If available, nebulized ipratropium bromide can be added to the regimen if side effects or poor response occurs to maximal dosages of beta-agonists. Nonconventional therapies should be considered only if conventional treatment fails. Signs and symptoms of deteriorating airflow and respiratory muscle fatigue should determine the need for mechanical ventilation. If mechanical ventilation is required, controlled hypoventilation may be best.
TL;DR: Noninvasive ventilatory equipment such as the nasal or oral masks, mouthpieces, bi-level positive airway pressure, chest cuirasses, ponchos, or the iron lung, and the rocking bed or pneumobelt can each ventilate a certain type of patient adequately and must be individualized to the patient's needs.
Abstract: Chronic hypoventilation syndrome can be caused by many disease states, although it is more commonly seen in neuromuscular disorders. Assessment of hypoventilation includes measurement of carbon dioxide level, respiratory muscle strength, pulmonary function testing, and any other system involved, such as cardiac dysfunction or sleep abnormalities. Often, chronic hypoventilation is initially diagnosed during an episode of acute respiratory failure. The use of noninvasive ventilation with positive pressure, negative pressure, or gravitational devices can be an effective treatment option for some patients, thus obviating the need for a tracheostomy. Noninvasive ventilatory equipment such as the nasal or oral masks, mouthpieces, bi-level positive airway pressure, chest cuirasses, ponchos, or the iron lung, and the rocking bed or pneumobelt can each ventilate a certain type of patient adequately. Each has specific indications, advantages, and disadvantages and must be individualized to the patient's needs.
TL;DR: Salient features of multiple dosing with diazepam and ketamine were hypoventilation, respiratory acidosis and an increase in both systemic and pulmonary vascular resistance.
Abstract: The cardiopulmonary effects of repeated intravenous injections of a combination of diazepam and ketamine for anaesthesia were evaluated in six domestic sheep. Induction doses of 0.375 mg/kg and 7.5 mg/kg were followed by maintenance doses of 0.188 mg/kg and 3.75 mg/kg every 15 minutes for 105 minutes. Although this dosing regimen produced the desired anaesthetic effects, it caused untoward cardiopulmonary effects. Salient features of multiple dosing with diazepam and ketamine were hypoventilation, respiratory acidosis and an increase in both systemic and pulmonary vascular resistance.
Journal Article•
TL;DR: An 11-year-old boy with a brainstem glioma whose initial symptoms included primary central hyperventilation was presented and oral morphine was administered in an attempt to decrease his respiratory rate.
Abstract: Alveolar ventilation and respiratory rate are regulated by central respiratory centers in the pons and medulla, which are influenced by both neural and humoral input. Aberrations in control mechanisms can lead to apnea, hypoventilation, or hyperventilation. Although hyperventilation usually occurs as a compensatory mechanism for metabolic derangements, primary central hyperventilation (CHV) has been reported with brainstem gliomas, central nervous system lymphoma, supratentorial lesions, and head trauma.1-3 We present an 11-year-old boy with a brainstem glioma whose initial symptoms included CHV. When CHV became unresponsive to primary tumor management with radiation therapy and administration of dexamethasone, oral morphine was administered in an attempt to decrease his respiratory rate.
TL;DR: The extent of compensatory hypoventilation in the setting of metabolic alkalosis in patients treated for ESRD and therapeutic approaches to this problem will be discussed.
Abstract: A patient with end-stage renal disease (ESRD) developed metabolic alkalosis and alkalemia from protracted vomiting. As a result of the absence of the alkali excretory capacity in this patient with ESR
TL;DR: Bi-level positive airway pressure therapy is a useful addition to the therapeutic armamentarium for patients with OSA as well as patients with compromised ventilatory muscle function and hypercapnia.
Abstract: Administration of bi-level positive airway pressure (BIPAP) via nasal mask can provide substantial benefit to patients with obstructive sleep apnea (OSA) and nocturnal alveolar hypoventilation. This modality maintains upper airway patency as well as assists patients in maintaining adequate ventilation during sleep without mandating oral/nasal tracheal intubation or tracheostomy. In OSA patients, BIPAP allows greater flexibility than conventional nasal continuous positive airway pressure (CPAP) by permitting independent adjustment of inspiratory and expiratory positive airway pressure (IPAP and EPAP, respectively). Therapy may therefore be achieved with lower expiratory pressure, improved patient comfort, and reduced mechanical impedance to ventilation with less potential for hypoventilation. Additionally, BIPAP allows patients to determine their own tidal volume, respiratory rate, and inspiratory flow. A back-up mode is also available in which the IPAP is delivered if the patient does not spontaneously initiate a breath within a prescribed interval. In this article we describe two representative OSA patients who underwent therapeutic trials of both nasal CPAP and BIPAP. In both patients, effective treatment was achieved at lower expiratory pressure and with greater comfort using BIPAP compared with CPAP. We also describe the effect of nocturnal BIPAP on a representative patient with ventilatory muscle weakness and chronic ventilatory failure. During sleep on BIPAP, there was improved alveolar ventilation and ventilatory muscle rest. On long-term home therapy with nocturnal BIPAP, there was a significant improvement in daytime alertness and performance of daily activities. We conclude that bi-level positive airway pressure therapy is a useful addition to the therapeutic armamentarium for patients with OSA as well as patients with compromised ventilatory muscle function and hypercapnia.
Journal Article•
TL;DR: The data available suggest, however, that it may be a contributory factor in the development of cardiac, cerebral and wound complications and rational therapeutic principles against late postoperative hypoxaemia should receive higher priority.
Abstract: Arterial hypoxaemia may be observed several days after an uncomplicated major surgical operation and may be of constant or episodic nature. Late postoperative constant hypoxaemia is mainly due to reduced pulmonary volume on account of reduced diaphragmatic function. The cause of late postoperative episodic hypoxaemia is probably opioid-induced alterations in regulation of respiration and alterations in sleep on account of pain and stress which cause intermittent hypoventilation and central and/or obstructive apnoea. The clinical significance of late postoperative hypoxaemia is not yet fully elucidated. The data available suggest, however, that it may be a contributory factor in the development of cardiac, cerebral and wound complications. The pathogenesis should, therefore, be elucidated and rational therapeutic principles against late postoperative hypoxaemia should receive higher priority.
Journal Article•
TL;DR: In patients with chronic renal failure spirometric and electromyographic examinations were performed before and after hemodialysis, a decreased myoelectrical activity of muscles was observed on the basis of amplitude of EMG.
Abstract: In 21 patients with chronic renal failure spirometric and electromyographic (included m. pectoralis, m. rectus abdomini, m. obligus abdomini) examinations were performed before and after hemodialysis. We observed a decreased myoelectrical activity of muscles on the basis of amplitude of EMG. Weakness of the respiratory muscles may be one of the causes of hypoventilation and hypoxemia during hemodialysis.
TL;DR: The patient showed typical frequent severe desaturations with hypopnea and the major diagnostic challenge was in differentiating primary cardiopulmonary disease from a central abnormality of ventilatory drive.
Journal Article•
TL;DR: A computer programme is developed for the differentiated assessment of cyclic and phasic oxygen desaturations and enables determination of the rate of incidence of various forms of desaturation during nocturnal recording.
Abstract: Nocturnal pulse oximetry is frequently used in screening studies when diagnosing nocturnal respiratory disorders. Short-term cyclic desaturations of oxygen can serve to indicate recurring apnoeas, whereas long-lasting phasic reductions of oxygen saturation are predominantly seen in hypoventilation. However, there are no uniform assessment criteria. We developed a computer programme for the differentiated assessment of cyclic and phasic oxygen desaturations. With this programme it is possible to characterise the individual phases in respect of gradient and duration of the decrease in oxygen saturation, of the starting, minimal and final values and the total duration of the desaturation phase. This enables determination of the rate of incidence of various forms of desaturation during nocturnal recording. The results of this differentiated analysis of nocturnal pulse oximetry in patients with sleep apnoea syndrome (n = 6) and with chronic obstructive airways disease with respiratory insufficiency (n = 6) and without respiratory insufficiency (n = 6) are demonstrated as model examples.
01 Jan 1991
TL;DR: A specially developed screening was used to examine workers of an assembly shop of a watch plant whose work is characterized by their being in a constrained position for hours which leads of general inactivity and hypoventilation, which can be the precursors of broncho-pulmonary diseases and later of tuberculosis.
Abstract: A specially developed screening was used to examine 652 workers of an assembly shop of a watch plant whose work is characterized by their being in a constrained position for hours which leads of general inactivity and hypoventilation. Disturbances of external respiratory function were found in 180 (27.6%) subjects, which is associated with their working conditions rather than with smoking. These subjects deserve special care since the pre-clinical obstructive bronchial changes can be the precursors of broncho-pulmonary diseases and later of tuberculosis.
TL;DR: Pulmonary complications occur most commonly in the elderly or high risk patient, in whom they account for substantial post-operative mortality and morbidity.
Journal Article•
TL;DR: A patient with combined obstructive sleep apnea and a hypoventilation syndrome due to obesity serves to illustrate problems with diagnosis and particularly treatment of this respiratory disorder during sleep.
Abstract: Nocturnal intrinsic disorders of sleep are much more common than hitherto assumed In middle-aged men, a prevalence of 03 to 3% of severe obstructive sleep apnea syndromes necessitating treatment is expected The international classification of sleep disorders (ICSD 1990) contains the definitions and descriptions of the different entities A patient with combined obstructive sleep apnea and a hypoventilation syndrome due to obesity serves to illustrate problems with diagnosis and particularly treatment of this respiratory disorder during sleep The most frequent sleep disorders are briefly presented and placed in the context of other concomitant somatic diseases Because of the possible serious course of nocturnal hypoxemias, the conclusion is justified that a timely and accurate diagnosis is essential for the patient Transcutaneous oximetry during the night is sufficient as screening procedure It can be applied to outpatients In depth, evaluation should be carried out at a specialized center with polysomnography
Journal Article•
TL;DR: A good correlation between arterial and end-tidal pCO2 in the overall patient population is found, but the relationship varied widely from patient to patient.
Abstract: We investigated the correlation between arterial and end-tidal pCO2 in 17 children during intensive care. The indications for using capnometry were noninvasive monitoring of ventilation after cardiac surgery or during complicated course of illness or for control of intended hyperventilation. We found a good correlation between arterial and end-tidal pCO2 in the overall patient population (r = 0.82), but the relationship varied widely from patient to patient. There was only a weak correlation (r = 0.44) in pCO2 over 45 mm Hg. Hyperventilation could be identified in 64.2%, whereas hypoventilation was correctly indicated in only 23%.