Intrinsic Lung Disease Research Articles

Respiratory Complications Between Cuffed and Uncuffed Endotracheal Tubes in Pediatric Respiratory Management After Palatoplasty: Single-Center Retrospective Cohort Study.

Retrospective cohort study. Operating room and PICU. Children without intrinsic lung disease who had undergone palatoplasty at a single institution. Inclusion criteria: intubation using ETTs with an internal diameter of 3.5 mm and postoperative management in the PICU. Exclusion criteria: 1) patients for whom ETTs with internal diameters other than 3.5 mm were used, 2) patients who had already been extubated in the operating room, and 3) patients who had a tracheostomy. None. Eighty-seven patients were screened for eligibility; 71 met the inclusion criteria. Of the 71 patients, 41 (58%) with polyurethane-cuffed ETTs (PUC-ETTs) and 30 (42%) with uncuffed ETTs were enrolled. We failed to identify an association between type of PUC-ETT and the development of atelectasis (odds ratio [OR], 1.06; 95% CI, 0.35-3.20; p = 1.00). Similarly, we failed to identify an association between type of PUC-ETT and development of stridor (OR, 1.58; 95% CI, 0.43-5.81; p = 0.715) or hoarseness after extubation (OR, 7.03; 95% CI, 0.83-59.6; p = 0.10). At extubation, air leak pressure was higher in the PUC-ETT group than in the uncuffed ETT group (p < 0.001), a finding which was not evident at intubation. The number of patients who received IV dexamethasone and the cases of inhaled racemic epinephrine were not statistically significant. In this select population of post-palatoplasty infants without intrinsic lung disease, we failed to identify any association between type of ETT (cuffed or uncuffed) and greater odds of developing respiratory complications. Taken together with the 95% CI of the effect size, our data indicate continued uncertainty about type of ETT that should be used for short-term intubation.

Nutrition implications of intrinsic restrictive lung disease.

Restrictive lung disease is defined as a reduction in lung volume that may be due to intraparenchymal or extraparenchymal causes. Intraparenchymal causes falls under the umbrella term of interstitial lung disease (ILD) and includes idiopathic pulmonary fibrosis. This manuscript provides an overview of ILD and can be beneficial for all clinicians working with patients with ILD. Although not well documented, the prevalence of malnutrition in patients with ILD has been reported to be between ~9% and 55%. Body mass index has been shown to predict survival; but more recently, research has suggested that fat-free mass has a larger influence on survival. There is insufficient evidence to support the use of antioxidant or vitamin supplementation to help diminish the chronic inflammatory process that is seen in this patient population. There are data from studies examining the vitamin D status in this patient population, but research on vitamin D supplementation appears to be lacking. Registered dietitian nutritionists should continue to advocate and play a more prominent role in the nutrition management of patients with ILD as part of standard of care.

Insights From Invasive Cardiopulmonary Exercise Testing of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) affects tens of millions worldwide; the causes of exertional intolerance are poorly understood. The ME/CFS label overlaps with postural orthostatic tachycardia (POTS) and fibromyalgia, and objective evidence of small fiber neuropathy (SFN) is reported in approximately 50%of POTS and fibromyalgia patients. Can invasive cardiopulmonary exercise testing (iCPET) and PGP9.5-immunolabeled lower-leg skin biopsies inform the pathophysiology of ME/CFS exertional intolerance and potential relationships with SFN? We analyzed 1,516 upright invasive iCPETs performed to investigate exertional intolerance. After excluding patients with intrinsic heart or lung disease and selecting those with right atrial pressures (RAP)<6.5mmHg, results from 160 patients meeting ME/CFS criteria who had skin biopsy test results were compared with 36 control subjects. Rest-to-peak changes in cardiac output (Qc) were compared with oxygen uptake (Qc/VO2 slope) to identify participants with low, normal, or high pulmonary blood flow by Qc/VO2 tertiles. During exercise, the 160 ME/CFS patients averaged lower RAP (1.9 ± 2 vs8.3 ± 1.5; P< .0001) and peak VO2 (80%± 21%vs101.4%± 17%; P< .0001) than control subjects. The low-flow tertile had lower peak Qc than the normal and high-flow tertiles (88.4%± 19%vs99.5%± 23.8%vs99.9%± 19.5%predicted; P< .01). In contrast, systemic oxygen extraction was impaired in high-flow vslow- and normal-flow participants (0.74%± 0.1%vs0.88 ± 0.11 vs0.86 ± 0.1; P< .0001) in association with peripheral left-to-right shunting. Among the 160 ME/CFS patient biopsies, 31%were consistent with SFN (epidermal innervation≤5.0%of predicted; P< .0001). Denervation severity did not correlate with exertional measures. These results identify two types of peripheral neurovascular dysregulation that are biologically plausible contributors to ME/CFS exertional intolerance-depressed Qc from impaired venous return, and impaired peripheral oxygen extraction. In patients with small-fiber pathology, neuropathic dysregulation causing microvascular dilation may limit exertion by shunting oxygenated blood from capillary beds and reducing cardiac return.

Emerging trends in inhaled drug delivery.

Ideally, inhaled therapy is driven by the needs of specific disease management. Lung biology interfaces with inhaler performance to allow optimal delivery of therapeutic agent for disease treatment. Inhalation aerosol products consist of the therapeutic agent, formulation, and device. The manufacturing specifications on each of the components, and their combination, allow accurate and reproducible control of measures of quality and in-vitro performance. These product variables in combination with patient variables, including co-ordination skill during inhaler use, intrinsic lung biology, disease and consequent pulmonary function, contribute to drug safety and efficacy outcomes. Due to the complexity of pulmonary drug delivery, predicting biological outcomes from first principles has been challenging. Ongoing research appears to offer new insights that may allow accurate prediction of drug behavior in the lungs. Disruptive innovations were characteristic of research and development in inhaled drug delivery at the end of the last century. Although there were relatively few new inhaled products launched in the first decade of the new millennium it was evident that the earlier years of exploration resulted in maturation of commercially successful technologies. A significant increase in new and generic products has occurred in the last decade and technical, regulatory and disease management trends are emerging. Some of these developments can trace their origins to earlier periods of creativity in the field while others are a reflection of advances in other areas of basic and computer, sciences and engineering. Select biological and technical advances are highlighted with reflections on the potential to impact future clinical and regulatory considerations.

EP.122Recurrent pneumothorax in an adult case of Ullrich congenital muscular dystrophy – case report and review of literature

Collagen VI related muscular dystrophy is caused by dominant or recessive mutations in the COL6A1, COL6A2 or COL6A3 genes and comprises of a spectrum of rare neuromuscular disorders including the early-onset and more severe Ulrich congenital muscular dystrophy, the milder adult form of Bethlem myopathy and an intermediate phenotype. They are characterised clinically by progressive muscle weakness, distal hyperlaxity, joint contractures and respiratory insufficiency. Respiratory failure develops with progression of the condition and is caused by respiratory muscle (diaphragm and intercostal) weakness as well as spinal and thoracic deformities. Intrinsic lung disease is not common, but pneumothorax, occurring as a single event or as recurrent episodes is being increasingly recognised in these patients. Our patient is a 22 year old female with Ulrich congenital muscular dystrophy caused by heterozygous mutation in exon 9 of COL6A1 gene. She was known to have a restrictive lung defect with scoliosis since childhood. Nocturnal ventilatory support was initiated at the age of 18 following a sleep study showing evidence of hypoventilation. She developed a spontaneous left sided pneumothorax at 21 years old, requiring intercostal drain (ICD) insertion followed by chemical pleurodesis via ICD. A contralateral spontaneous pneumothorax occurred 8 months later, which was complicated by PEA arrest requiring intubation and ventilation; followed by a protracted recovery period. This case is being presented to increase the awareness of a potentially life threatening complication associated with this condition. A first presentation of spontaneous pneumothorax in these patients should lead to careful assessment of lung parenchymal changes and consideration of definitive pre-emptive contralateral intervention.

Heart-lung transplantation: current indications, prognosis and specific considerations.

Heart-lung transplantation (HLTx) is currently the best treatment for patients who have end-stage heart and lung failure. Idiopathic pulmonary arterial hypertension (IPAH) was the main indication for HLTx in the 1980s. However, when studies showed resolution of right ventricular dysfunction after double-lung transplantation (DLTx), this last procedure became the preferred option for end-stage IPAH. Currently, the main indication of HLTx is congenital heart disease (CHD), followed by acquired heart disease combined with pulmonary hypertension and/or intrinsic lung disease. Although early posttransplant survival remains lower after HLTx than after lung transplantation, careful patient selection combined with surgical advances are producing improvements. Here, we review the practice patterns, trends, and outcomes of HLTx worldwide.

It's Not the Lung! When a Neuromuscular Disease Presented as Recurrent Episodes of Shortness of Breath

SESSION TITLE: Pulmonary Manifestations of Systemic Disease 2 SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Recurrent episodes of shortness of breath and consequences of respiratory failure despite treatment requires reconsideration as such presentations may be due to a neuromuscular disease. CASE PRESENTATION: A 66yo male with a past medical history of hypertension and diastolic heart failure with EF 55% presents with progressively worsening dyspnea on exertion and multiple hospitalizations for hypoxic respiratory failure. CT chest revealed nonspecific bibasilar consolidations consistent with either atelectasis, aspiration, or pneumonia. Lung function demonstrated a mild restrictive defect, no obstruction, normal diffusion capacity, and no bronchodilator response. Patient improved with a trial of steroids but his clinical status continued to decline. Further history revealed loss of energy, generalized muscle weakness, joint pain, dysphagia with liquids but not solids, orthopnea, and dyspnea resulting in significant decrease in functional capacity to the point he was unable to use a sweeper around his house. Physical exam revealed central muscle wasting. Patient was urgently referred to Neurology and a motor nerve conduction study was obtained due to suspicion of a neuromuscular disorder. EMG of the upper and lower extremities showed abnormal activity and chronic neurogenic changes in multiple myotomes with decreased recruitment, consistent with an acute on chronic denervation process. After clinical evaluation, patient was formally diagnosed with ALS by Neurology. DISCUSSION: Amyotrophic lateral sclerosis (ALS) is a progressive neuromuscular degenerative disease of the upper and lower motor neurons resulting in muscle weakness, fasciculations, atrophy, and hyper-reflexia. Presentation is variable but is most often either bulbar, with complaints of dysphagia or dysarthria, or spinal, with complaints of muscle weakness and gait instability. However, dyspnea is seldom the primary symptom at presentation. Diagnosis is multifaceted and individualized, requiring a thorough history and physical examination. Advanced studies such as electromyography are utilized to demonstrate denervation in the limbs. When left untreated, major morbidity and mortality in the form of chronic aspiration, secretion retention, or pneumonia may result. Despite the lack of a cure, various medications and assist devices may prolong and improve the overall quality of life and mortality. CONCLUSIONS: Shortness of breath, though a common symptom for an underlying intrinsic lung disease such as pneumonia or COPD, may actually be the result of a neuromuscular disorder. A careful history and physical exam from a pulmonary standpoint is crucial to the aid in diagnosis. Reference #1: Pavletic, Adriana J., and Oleh Hnatiuk. “Puzzling Dyspnea Caused by Respiratory Muscle Weakness.” Journal of the American Board of Family Medicine: JABFM (2012); 25.3:396-397. Reference #2: Rowland, Lewis, and Shneider, Neil. “Amyotrophic Lateral Sclerosis”. The New England Journal of Medicine: NEJM (2001); 344:1688-1700. DISCLOSURE: The following authors have nothing to disclose: Meilin Young, Tiffany Dumont, Anil Singh No Product/Research Disclosure Information

Pneumothoraces in collagen VI-related dystrophy: a case series and recommendations for management.

Collagen VI-related dystrophy (collagen VI-RD) is a rare neuromuscular condition caused by mutations in the COL6A1, COL6A2 or COL6A3 genes. The phenotypic spectrum includes early-onset Ullrich congenital muscular dystrophy, adult-onset Bethlem myopathy and an intermediate phenotype. The disorder is characterised by distal hyperlaxity and progressive muscle weakness, joint contractures and respiratory insufficiency. Respiratory insufficiency is attributed to chest wall contractures, scoliosis, impaired diaphragmatic function and intercostal muscle weakness. To date, intrinsic parenchymal lung disease has not been implicated in the inevitable respiratory decline of these patients.This series focuses on pneumothorax, an important but previously under-recognised disease manifestation of collagen VI-RD.We describe two distinct clinical presentations within collagen VI-RD patients with pneumothorax. The first cohort consists of neonates and children with a single pneumothorax in the setting of large intrathoracic pressure changes. The second group is made up of adult patients with recurrent pneumothoraces, associated with chest computed tomography scan evidence of parenchymal lung disease. We describe treatment challenges in this unique population with respect to expectant observation, tube thoracostomy and open pleurodesis.Based on this experience, we offer recommendations for early identification of lung disease in collagen VI-RD and definitive intervention.

Airway Management in Patients With Abnormal Anatomy or Challenging Physiology

Most pediatric intubations that occur in the emergency department are in patients without identifiable risk factors for difficulty. Infants and children go through a predictable pattern of development that impacts airway management. A careful, stepwise approach to the identification of the truly difficult pediatric airway is critical to avoid morbidity and mortality. Difficulty can be encountered in cases of challenging anatomy such as congenital airway or midface abnormalities or with acquired conditions such as croup or epiglottitis. Physiologically, intrinsic lung disease (ie, asthma) and shock states have unique features that impact airway management.

Un caso de "Mal de montaña crónico" en los Estados Unidos

1.- Se decribe un caso de Mal de Montaña crónico en un residente de las Montañas Rocallosas de Colorado. Se han hecho estudios clínicos, electrocardiográficos y de fisiología cardio-pulmonar. Los síntomas, signos y anormalidades electrocardiográficas desaparecieron al descender el paciente al nivel del mar. Sin embargo, se ha podido poner en evidencia una enfermedad pulmonar ligera, intensamente persistente, después de residencia a nivel del mar por más de dos años. 2.- Puede suponerse que algunos casos del Mal de Montaña crónico son el resultado de perturbaciones en el cambio respiratorio de gases y de alteraciones de los índices de ventilación perfusión basados de una enfermedad pulmonar intrínseca, sumamente ligera para ocasionar signos o síntomas al nivel del mar.

Extreme Obesity in the Intensive Care Unit

Extreme obesity is currently a common medical condition. It is defined as having a body mass index (BMI) of >40 kg/m and is associated with an increased risk of mortality. A review of the clinical literature has shown that extreme obese patients are commonly admitted to the intensive care unit (ICU) for obstructive airway disease, pneumonia, and sepsis. A recent study found that patients with a BMI of >40 kg/m required greater mechanical ventilation and, therefore, a corresponding prolonged stay in the ICU. What are the other factors affecting the outcome of extreme obese patients in the ICU? In this issue of the Journal of Intensive Care Medicine, a new obesity-related condition among patients in the ICU with obesity hypoventilation syndrome (OHS) is now being described. The OHS is defined as the triad of obesity, daytime hypoventilation, and sleep-disordered breathing in the absence of an alternative neuromuscular, mechanical, or metabolic explanation for the hypoventilation episodes. Given this definition, a subtype condition has been identified in the extreme obese patients who had hypercapnic respiratory failure and multiorgan system dysfunction related to obesity, labeled as malignant obesity hypoventilation syndrome (MOHS). Marik and Desai coined this new term using a retrospective electronic chart review of 61 patients admitted to the ICU with a BMI of >40 kg/m and a PaCO2 greater than 45 mm Hg in patients admitted with hypercapnic respiratory failure. Supporting the description of MOHS, a statistical analysis of the documentation from this study confirmed the presence of multisystem disorder in extreme obesity by finding that 86% of the patients had congestive heart failure treated with diuretics, 71% had left ventricular failure, 61% had left ventricular diastolic dysfunction, 77% had pulmonary hypertension above 45 mm Hg, 90% had essential hypertension, and 64% had abnormal liver function tests and diagnosed with nonalcoholic steatohepatitis. Moreover, this retrospective study showed that based on the clinical documentation, these patients fit the clinical criteria for OHS, however, only 3 were diagnosed with this condition and the remaining (75%) were diagnosed with and treated for chronic obstructive lung disease (COPD). A primary question that arises after reading the study of Marik and Desai is ‘‘Are patients with extreme obesity admitted to the ICU with a diagnosis of COPD/asthma being misdiagnosed when in fact they could have unrecognized OHS?’’ It is known that patients with extreme obesity statistically have hypercapnic respiratory failure that increases the length of stay in the ICU due to prolonged necessity for mechanical ventilation. It is also well known that hypoventilation and oxygen disturbances are related to obesity even if there is no intrinsic lung disease. Therefore, mechanical ventilation in the extreme obese patient is one of many challenges clinicians face since the increase in the prevalence of obesity, with a corresponding increase in ICU admissions. It is very concerning that only 3 of 61 patients had a confirmed diagnosis of OHS. More interestingly, the management of extreme obese patients with bilevel positive airway pressure (BiPAP) in this study failed in 23% of the patients, thus requiring mechanical ventilation. This was an unexpected finding which highlights again the challenge of managing respiratory failure and the use of mechanical ventilation in extremely obese patients. What would have happened if OHS was part of the medical history of these patients admitted to the ICU? It is well known that extremely obese patients with concomitant untreated obstructive sleep apnea (OSA) present

Characteristics of Patients With the “Malignant Obesity Hypoventilation Syndrome” Admitted to an ICU

The incidence of obesity in westernized nations is increasing at an alarming rate. We have noted an increasing number of patients admitted to our intensive care unit (ICU) with hypercapnic respiratory failure and multisystem organ dysfunction related to obesity. We have coined the term the malignant obesity hypoventilation syndrome (MOHS) to describe this entity. We reviewed the hospital records of all patients who were admitted to our ICU over an 8-month period, with a body mass index (BMI) greater than 40 kg/m² and a PaCO₂ greater than 45 mm Hg. We excluded patients with musculoskeletal disease, intrinsic lung disease, and those with >20 pack-year smoking history. Sixty-one patients (8% of all admissions) met the inclusion criteria for our study. The patients' mean BMI was 48.9 ± 8.6 kg/m². The patients' mean age was 59 ± 11; 47 (77%) were female and 56 (92%) were black. All patients were admitted to the ICU with hypercapnic respiratory failure. The patients had been admitted to our hospital on average 6 times over the previous 2 years; 75% had been erroneously diagnosed and treated for chronic obstructive pulmonary disease (COPD)/asthma and 86% had been treated with diuretics for congestive cardiac failure. All patients had type 2 diabetes and the metabolic syndrome. Three patients had a tracheotomy in place at admission and required mechanical ventilation. All of the remaining patients were treated with noninvasive bilevel positive airway pressure (BiPAP), with 23 patients failing BiPAP and requiring mechanical ventilation. Seven patients had a tracheotomy performed. On the basis of unexplained abnormalities of liver function tests, 39 patients (64%) were presumptively diagnosed with nonalcoholic steatohepatitis (NASH). Pulmonary function tests were suggestive of a restrictive pattern in all patients tested. By echocardiography 43 (71%) patients had left ventricular hypertrophy and 37 (61%) patients had features of left ventricular diastolic dysfunction. Forty-seven (77%) patients had pulmonary hypertension, which was moderate to severe (pulmonary systolic pressure >45 mm Hg) in 25 cases. All patients had an elevated C-reactive protein (9.4 ± 6.9 mg/dL), and all but 1 were vitamin D deficient (13.5 ± 8.5 ng/mL). Eleven patients (18%) died during the index hospitalization. MOHS is a serious multisystem disorder with a high mortality that appears to be relatively common, frequently misdiagnosed, and inadequately treated.

Patient-Controlled Analgesia: Is It Worth the Painful Prescribing Process?

In the last 10 years, the assessment and treatment of pain have become a priority for health care organizations, especially after the introduction of regulatory standards and patient satisfaction surveys directly correlating pain control with a favorable satisfaction score. While much of the focus is on increasing the number of patients receiving adequate pain relief, there has been a subsequent increase in overaggressive attempts to ensure comfort (1). Severe acute pain is best treated with intermittent, intravenous doses of opioids, which allow rapid titration of effect. Appropriately and accurately prescribed patient-controlled analgesia (PCA) is an effective and efficient method of controlling severe acute pain; the risk of oversedation is significantly reduced, and there is considerable potential to improve pain management for patients (2, 3). PCA allows patients to self-administer more frequent but smaller doses of analgesia than the traditional nurse-administered larger and less frequent bolus doses, thus making PCA a favorable choice to comply with standards and patients' goals for comfort. PCA offers advantages especially when protocols are in place to assess the level of pain and sedation; assess the rate, depth, and quality of respirations; perform a preprocedure cognitive assessment; and note whether the patient is opioid tolerant or naive. However, serious unintended consequences such as oversedation, respiratory depression, and undertreated pain may occur from the use of PCA. Contributing factors that lead to these events include improper patient selection, inadequate patient monitoring, pump programming errors, PCA by proxy, patients' self-administration of home analgesics while receiving PCA, imprudent polypharmacy, and insufficient health care team member training or education about medications administered via PCA and their dosing and lockout periods. Adverse events due to one of these many contributing factors are preventable and can be significantly reduced with guidance for treatment team staff, patients, and family members. Numerous adverse event reports totaling in the thousands and a few resulting in patient harm or fatality have occurred since the introduction of PCA (4). In response, the Institute for Safe Medication Practices (ISMP) and the Joint Commission have issued a number of PCA-related safety alerts to health care organizations (2, 3, 5–8). Based on these warnings, many organizations have formed focused, team-based approaches to review PCA-related events and design measures to address the contributing factors leading to these events. Much of the focus is on five areas: patient selection, prescribing errors, staff training, monitoring, and patient education. Developing criteria for selecting appropriate patients to receive PCA is one of the most overlooked but preventable mechanisms to significantly impact events. Well-documented risk factors for oversedation and respiratory depression include opioid-naive status, obesity, age, mental status, and multiple comorbid conditions such as intrinsic lung disease, obstructive sleep apnea (OSA), and renal and hepatic impairment.

Recalibrating the Barometer

The ability to measure pressures within the heart has been one of the most important diagnostic and therapeutic tools within the cardiologist’s armamentarium over the past half century. Whereas this measurement initially required direct left ventricular puncture,1 transeptal catheterization,2 or retrograde placement of a catheter into the left ventricle, the advent of the Swan-Ganz catheter allowed for accurate estimation of left-sided filling pressures without requiring arterial or intraventricular access. These measurements have been useful to diagnose and treat hemodynamic compromise resulting from cardiac and pulmonary disease and other critical conditions associated with abnormal or unknown volume status. Article p 62 Accurate assessment of left-sided intracardiac filling pressures is particularly crucial for the management of chronic heart failure, in which congestion causes most of the disabling symptoms and hospitalizations.3 High left-sided filling pressures predict rehospitalizations and death, and the degree to which pressures can be reduced predicts survival.4 Skilled estimation of jugular venous pressure, particularly in conjunction with orthopnea, provides the most reliable clinical evidence of elevated left-sided filling pressures.5 However, the accuracy of jugular venous pressure for the detection of elevated right atrial pressure is <75%. The concordance of right-sided and left-sided pressures is about 75% in chronic heart failure without known pulmonary disease,6 and lower when intrinsic lung or pulmonary vascular disease may uncouple ventricular filling pressures. Brain natriuretic peptide levels do not add to the clinical examination in assessing the elevation of filling pressures during admission with chronic heart failure5 and do not change rapidly enough to guide therapy in the inpatient setting7. A reliable noninvasive method to assess elevated filling pressures and their reduction during therapy would refine our current approach to therapy of decompensated heart failure. Noninvasive approaches to measuring intracardiac pressures, particularly diastolic pressures, have been …

Clinical Guidelines for the Manual Titration of Positive Airway Pressure in Patients with Obstructive Sleep Apnea

Positive airway pressure (PAP) devices are used to treat patients with sleep related breathing disorders (SRBDs), including obstructive sleep apnea (OSA). After a patient is diagnosed with OSA, the current standard of practice involves performing attended polysomnography (PSG), during which positive airway pressure is adjusted throughout the recording period to determine the optimal pressure for maintaining upper airway patency. Continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BPAP) represent the two forms of PAP that are manually titrated during PSG to determine the single fixed pressure of CPAP or the fixed inspiratory and expiratory positive airway pressures (IPAP and EPAP, respectively) of BPAP for subsequent nightly usage. A PAP Titration Task Force of the American Academy of Sleep Medicine reviewed the available literature. Based on this review, the Task Force developed these recommendations for conducting CPAP and BPAP titrations. Major recommendations are as follows: (1) All potential PAP titration candidates should receive adequate PAP education, hands-on demonstration, careful mask fitting, and acclimatization prior to titration. (2) CPAP (IPAP and/or EPAP for patients on BPAP) should be increased until the following obstructive respiratory events are eliminated (no specific order) or the recommended maximum CPAP (IPAP for patients on BPAP) is reached: apneas, hypopneas, respiratory effort-related arousals (RERAs), and snoring. (3) The recommended minimum starting CPAP should be 4 cm H2O for pediatric and adult patients, and the recommended minimum starting IPAP and EPAP should be 8 cm H2O and 4 cm H2O, respectively, for pediatric and adult patients on BPAP. (4) The recommended maximum CPAP should be 15 cm H2O (or recommended maximum IPAP of 20 cm H2O if on BPAP) for patients or = 12 years. (5) The recommended minimum IPAP-EPAP differential is 4 cm H2O and the recommended maximum IPAP-EPAP differential is 10 cm H2O (6) CPAP (IPAP and/or EPAP for patients on BPAP depending on the type of event) should be increased by at least 1 cm H2O with an interval no shorter than 5 min, with the goal of eliminating obstructive respiratory events. (7) CPAP (IPAP and EPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 obstructive apnea is observed for patients or = 12 years. (8) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 hypopnea is observed for patients or = 12 years. (9) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 3 RERAs are observed for patients or = 12 years. (10) CPAP (IPAP for patients on BPAP) may be increased from any CPAP (or IPAP) level if at least 1 min of loud or unambiguous snoring is observed for patients or = 12 years. (11) The titration algorithm for split-night CPAP or BPAP titration studies should be identical to that of full-night CPAP or BPAP titration studies, respectively. (12) If the patient is uncomfortable or intolerant of high pressures on CPAP, the patient may be tried on BPAP. If there are continued obstructive respiratory events at 15 cm H2O of CPAP during the titration study, the patient may be switched to BPAP. (13) The pressure of CPAP or BPAP selected for patient use following the titration study should reflect control of the patient's obstructive respiration by a low (preferably 3 hr).

Section 11: Evaluation and Management of Patients With Heart Failure and Preserved Left Ventricular Ejection Fraction

Section 11: Evaluation and Management of Patients With Heart Failure and Preserved Left Ventricular Ejection Fraction

One-Lung Anesthesia Update

One-lung ventilation is used during a variety of cardiac, thoracic, and major vascular procedures. Endobronchial tubes, bronchial blockers, and occasionally, single-lumen tubes are used to isolate the lungs. Patients with difficult airways and pediatric patients provide special challenges for lung isolation. Finally, intraoperative hypoxia and hypercarbia in patients with intrinsic lung disease frequently complicate one-lung anesthesia. The concepts and controversies in lung isolation techniques are discussed.

Pulmonary Complications After Cardiac Surgery

Over the past two decades there has been a steady evolution in the practice of adult cardiac surgery with the introduction of "off-pump" surgery. However, respiratory complications remain a leading cause of postcardiac surgical morbidity and can prolong hospital stays and increase costs. The high incidence of pulmonary complications is in part due to the disruption of normal ventilatory function that is inherent to surgery in the thoracic region. Furthermore, patients undergoing such surgery often have underlying illnesses such as intrinsic lung disease (e.g., chronic obstructive pulmonary disease) and pulmonary dysfunction secondary to cardiac disease (e.g., congestive heart failure) that increase their susceptibility to postoperative respiratory problems. Given that many patients undergoing cardiac surgery are thus susceptiple to pulmonary complications, it is remarkable that more patients do not suffer from them during and after cardiac surgery. This is to a large degree because of advances in anesthetic, surgical and critical care that, for example, have reduced the physiological insults of surgery (e.g., better myocardial preservation techniques) and streamlined care in the immediate postoperative period (e.g., early extubation). Moreover, the development of minimally invasive surgery and nonbypass techniques are further evidence of the attempts at reducing the homeostatic disruptions of cardiac surgery. This review examines the available information on the incidences, consequences, and treatments of postcardiac surgery respiratory complications.

Hypercapnic Respiratory Failure in Systemic Sclerosis

Respiratory failure from causes exclusive of intrinsic lung disease is rare in systemic sclerosis. We report an unusual case of a young woman with diffuse systemic sclerosis who presented with proximal muscle weakness, dyspnea, weight loss, and nasal regurgitation. On physical examination, she had normal breath sounds but severe limitation of chest wall expansion. Pulmonary function tests (PFTs) were consistent with restrictive lung disease. Pulmonary pressures were normal on right heart catheterization and chest radiography and high-resolution computed tomography showed no evidence of intrinsic lung disease. Quadriceps muscle biopsy was consistent with type II atrophy, without any element of inflammatory myositis. After a meal, the patient aspirated, developed severe persistent hypercapnia, and required ventilatory support. Therapy with corticosteroids and intravenous gamma globulin failed to improve her condition, and the patient subsequently expired. Hypercapnic respiratory failure on the basis of chest wall involvement from systemic sclerosis may occur in the absence of intrinsic lung disease, and the prognosis, as in this case, may be grave.

Pulmonary complications of inflammatory myopathy.

Pulmonary manifestations contribute significantly to the morbidity and mortality of the idiopathic inflammatory myopathies, ranging from intrinsic lung disease to secondary complications that include aspiration pneumonia, opportunistic infection, congestive heart failure, and hypoventilation. Newer classification schemes for interstitial lung disease have permitted closer correlation between histologic subtype and clinical outcome, while diagnostic techniques such as bronchoalveolar lavage have begun to define the cellular elements responsible for immune-mediated pulmonary dysfunction. Investigators have identified several serum markers correlating with inflammatory disease activity in the lung that should enhance noninvasive monitoring of therapeutic responses to newer regimens involving agents such as cyclosporine and tacrolimus. Taken together, these advances have contributed to better understanding of the immunopathogenesis of myositis-associated interstitial lung disease that should ultimately translate into more effective treatment.