ResUHUrge: A Low Cost and Fully Functional Ventilator Indicated for Application in COVID-19 Patients.

Although the cure for the SARS-CoV-2 virus (COVID-19) will come in the form of pharmaceutical solutions and/or a vaccine, one of the only ways to face it at present is to guarantee the best quality of health for patients, so that they can overcome the disease on their own. Therefore, and considering that COVID-19 generally causes damage to the respiratory system (in the form of lung infection), it is essential to ensure the best pulmonary ventilation for the patient. However, depending on the severity of the disease and the health condition of the patient, the situation can become critical when the patient has respiratory distress or becomes unable to breathe on his/her own. In that case, the ventilator becomes the lifeline of the patient. This device must keep patients stable until, on their own or with the help of medications, they manage to overcome the lung infection. However, with thousands or hundreds of thousands of infected patients, no country has enough ventilators. If this situation has become critical in the Global North, it has turned disastrous in developing countries, where ventilators are even more scarce. This article shows the race against time of a multidisciplinary research team at the University of Huelva, UHU, southwest of Spain, to develop an inexpensive, multifunctional, and easy-to-manufacture ventilator, which has been named ResUHUrge. The device meets all medical requirements and is developed with open-source hardware and software.

Cost Savings from Reduced Hospitalizations with Use of Home Noninvasive Ventilation for COPD.

BACKGROUND: Although evidence suggests significant clinical benefits of home noninvasive ventilation (NIV) for management of severe chronic obstructive pulmonary disease (COPD), economic analyses supporting the use of this technology are lacking. OBJECTIVES: To evaluate the economic impact of adopting home NIV, as part of a multifaceted intervention program, for severe COPD. METHODS: An economic model was developed to calculate savings associated with the use of Advanced NIV (averaged volume assured pressure support with autoexpiratory positive airway pressure; Trilogy100, Philips Respironics, Inc., Murrysville, PA) versus either no NIV or a respiratory assist device with bilevel pressure capacity in patients with severe COPD from two distinct perspectives: the hospital and the payer. The model examined hospital savings over 90 days and payer savings over 3 years. The number of patients with severe COPD eligible for home Advanced NIV was user-defined. Clinical and cost data were obtained from a quality improvement program and published reports. Scenario analyses calculated savings for hospitals and payers covering different COPD patient cohort sizes. RESULTS: The hospital base case (250 patients) revealed cumulative savings of $402,981 and $449,101 over 30 and 90 days, respectively, for Advanced NIV versus both comparators. For the payer base case (100,000 patients), 3-year cumulative savings with Advanced NIV were $326 million versus no NIV and $1.04 billion versus respiratory assist device. CONCLUSIONS: This model concluded that adoption of home Advanced NIV with averaged volume assured pressure support with autoexpiratory positive airway pressure, as part of a multifaceted intervention program, presents an opportunity for hospitals to reduce COPD readmission-related costs and for payers to reduce costs associated with managing patients with severe COPD on the basis of reduced admissions.

Noninvasive ventilation in acute severe asthma: current evidence and future perspectives.

PURPOSE OF REVIEW: The use of noninvasive positive pressure ventilation (NPPV) is often employed for the management of acute respiratory failure as an alternative to endotracheal intubation and mechanical ventilation. However, evidence to support the application of NPPV use in patients with acute severe asthma is less known. RECENT FINDINGS: A paucity of evidence is available to support the use of NPPV as part of clinical care in patients with acute severe asthma. A number of small studies in adult and paediatric populations suggest that NPPV may have a beneficial role through improving respiratory rate and reducing the need for more invasive alternatives. Overall NPPV use appeared to be well tolerated with few reports of adverse events. SUMMARY: Available evidence is limited by a small number of published trials and lack of methodological rigour in existing study design. There is a need for well conducted clinical studies to establish accurate treatment efficacy, safety and cost-effectiveness, in both the adult and paediatric setting.

Non-invasive ventilation in acute respiratory failure.

Non-invasive mechanical ventilation has been increasingly used to avoid or serve as an alternative to intubation. Compared with medical therapy, and in some instances with invasive mechanical ventilation, it improves survival and reduces complications in selected patients with acute respiratory failure. The main indications are exacerbation of chronic obstructive pulmonary disease, cardiogenic pulmonary oedema, pulmonary infiltrates in immunocompromised patients, and weaning of previously intubated stable patients with chronic obstructive pulmonary disease. Furthermore, this technique can be used in postoperative patients or those with neurological diseases, to palliate symptoms in terminally ill patients, or to help with bronchoscopy; however further studies are needed in these situations before it can be regarded as first-line treatment. Non-invasive ventilation implemented as an alternative to intubation should be provided in an intensive care or high-dependency unit. When used to prevent intubation in otherwise stable patients it can be safely administered in an adequately staffed and monitored ward.

A timeline for predicting durable medical equipment needs and interventions for amyotrophic lateral sclerosis patients.

ALS is progressive with increasing patient needs for durable medical equipment (DME) and interventions (gastric feeding tube - PEG, and non-invasive ventilation - NIV). We performed a chart review of deceased patients to determine the time-course of needs and their estimated costs. A timeline of needs was based on when clinic personnel felt an item was necessary. The point in time when an item or intervention was needed was expressed as a percentage of a patient's total disease duration. A wide range of DME and interventions was needed irrespective of site of ALS symptom onset (bulbar, upper, lower extremity), beginning at 10% of disease duration of lower extremity onset and increasing thereafter for all sites. The cumulative probability of costs of items and interventions began at 25%-50% of disease duration and increased to between $18,000 and $32,000 (USD), highest for lower extremity onset due to the cost of wheelchairs. We conclude that a high percentage of ALS patients will need a full spectrum of major DME items and interventions during the second half of disease duration. This results in a linear rise in costs over the second half of the disease duration.

Cost-Effectiveness of the Aerobika® Oscillating Positive Expiratory Pressure Device in the Management of Chronic Obstructive Pulmonary Disease Exacerbations in Canada.

Background: The Aerobika® oscillating positive expiratory pressure (OPEP) device is a hand-held, drug-free medical device that has been shown to improve lung function and improve health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). We estimated the cost-effectiveness of this device among postexacerbation COPD patients in the Canadian healthcare system. Methods: We performed a cost-utility analysis using a Markov model to compare both costs and outcome of patients with COPD who had recently experienced an exacerbation between 2 treatment arms: patients who used the Aerobika® device and patients who did not use the Aerobika® device. This cost-utility analysis included costs based on the Alberta healthcare system perspective as these represent Canadian experience. A one-year horizon with 12 monthly cycles was used. Results: For a patient after 1 year, the use of the Aerobika® device would save $694 in healthcare costs and produce 0.04 more in quality-adjusted life years (QALYs) in comparison with no positive expiratory pressure (PEP)/OPEP therapy. In other words, the economic outcome of the device was dominant (i.e., more effective and less costly). The probability for this device to be the dominant strategy was 72%. With a willingness to pay (WTP) threshold of $50,000 per QALY gained, the probability for the Aerobika® device to be cost-effective was 77%. Conclusions: Given one of the major treatment goals in the GOLD guidelines is to minimize the negative impact of exacerbations and prevent re-exacerbations, the Aerobika® OPEP device should be viewed as a potential component of a treatment strategy to improve symptom control and reduce the risk of re-exacerbations in patients with COPD.

Cost-effectiveness of the Aerobika* oscillating positive expiratory pressure device in the management of COPD exacerbations.

INTRODUCTION: COPD places a huge clinical and economic burden on the US health care system, with acute exacerbations representing a key driver of direct medical costs. Current treatments, although effective in reducing symptoms and limiting exacerbations, do not adequately target the underlying disease processes that drive exacerbation development. The Aerobika* oscillating positive expiratory pressure (OPEP) device has been shown in a real-world effectiveness study to lower the frequency of moderate-to-severe exacerbations during a 30-day post-exacerbation period. This study sought to determine the impact on exacerbations and costs and to determine the cost-effectiveness of the Aerobika* device. METHODS: Data from published literature and national fee schedules were used to model the cost-effectiveness of the Aerobika* device in patients who had experienced an exacerbation in the previous month, or a post-exacerbation care population. Exacerbation trends and the impact of the Aerobika* device on reducing exacerbation frequency were modeled using a one-year Markov model with monthly cycles and three health states: (i) no exacerbation, (ii) exacerbation, and (iii) death. Scenario analysis and one-way sensitivity analysis (OWSA) were also performed. RESULTS: When the effect of Aerobika* device was assumed to last 30 days, use of the device resulted in cost-savings ($553 per patient) and improved outcomes (ie, six fewer exacerbations per 100 patients per year) compared to no OPEP/positive expiratory pressure therapy. When the effect of the Aerobika* device was assumed to extend beyond the conservative 30-day time frame, the Aerobika* device remained the dominant strategy (21 fewer exacerbations per 100 patients per year; cost savings of $1,952 per patient). Consistency in findings after performing OWSAs indicates the robustness of results. CONCLUSION: The Aerobika* device is a cost-effective treatment option that provides clinical benefit and results in direct medical cost savings in a post-exacerbation care COPD population.

Screening for obstructive sleep apnea in stroke patients: a cost-effectiveness analysis.

BACKGROUND AND PURPOSE: Obstructive sleep apnea (OSA) is common after acute ischemic stroke and predicts poor stroke recovery, but whether screening for OSA and treatment by continuous positive airway pressure (CPAP) improves neurological outcome is unknown. We used a cost-effectiveness model to estimate the magnitude of benefit that would be necessary to make polysomnography (PSG) and OSA treatment cost-effective in stroke patients. METHODS: A decision tree modeled 2 alternative strategies: PSG followed by 3 months of CPAP for those found to have OSA versus no screening. The primary outcome was the utility gained through OSA screening and treatment in relation to 2 common willingness-to-pay thresholds of $50,000 and $100,000 per quality-adjusted life year (QALY). RESULTS: Screening resulted in an incremental cost-effectiveness ratio of $49,421 per QALY. Screening is cost-effective as long as the treatment of stroke patients with OSA by CPAP improves patient utilities by >0.2 for a willingness-to-pay of $50,000 per QALY and 0.1 for a willingness-to-pay of $100,000 per QALY. CONCLUSIONS: A clinical trial assessing the effectiveness of CPAP in improving stroke outcome is warranted from a cost-effectiveness standpoint.

The cost-effectiveness of early noninvasive ventilation for ALS patients.

BACKGROUND: Optimal timing of noninvasive positive pressure ventilation (NIPPV) initiation in patients with amyotrophic lateral sclerosis (ALS) is unknown, but NIPPV appears to benefit ALS patients who are symptomatic from pulmonary insufficiency. This has prompted research proposals of earlier NIPPV initiation in the ALS disease course in an attempt to further improve ALS patient quality of life and perhaps survival. We therefore used a cost-utility analysis to determine a priori what magnitude of health-related quality of life (HRQL) improvement early NIPPV initiation would need to achieve to be cost-effective in a future clinical trial. METHODS: Using a Markov decision analytic model we calculated the benefit in health-state utility that NIPPV initiated at ALS diagnosis must achieve to be cost-effective. The primary outcome was the percent utility gained through NIPPV in relation to two common willingness-to-pay thresholds: 50,000 dollars and 100,000 dollars per quality-adjusted life year (QALY). RESULTS: Our results indicate that if NIPPV begun at the time of diagnosis improves ALS patient HRQL as little as 13.5%, it would be a cost-effective treatment. Tolerance of NIPPV (assuming a 20% improvement in HRQL) would only need to exceed 18% in our model for treatment to remain cost-effective using a conservative willingness-to-pay threshold of 50,000 dollars per QALY. CONCLUSION: If early use of NIPPV in ALS patients is shown to improve HRQL in future studies, it is likely to be a cost-effective treatment. Clinical trials of NIPPV begun at the time of ALS diagnosis are therefore warranted from a cost-effectiveness standpoint.

Efficacy and cost of home-initiated auto-nCPAP versus conventional nCPAP.

STUDY OBJECTIVES: To compare in a multicenter prospective study the efficacy and cost of conventional nasal continuous positive airway pressure (nCPAP) initiated at the sleep laboratory versus auto-nCPAP initiated at home. DESIGN: Patients with severe obstructive sleep apnea syndrome (OSAS) were randomized to treatment with either the REM+ auto device in constant mode at the effective pressure determined by titration at the sleep laboratory (n=17) or the REM+ auto device in automatic mode initiated at the patients home by a nurse (n=18). After 2 months, the efficacy and cost of nCPAP therapy and the time from diagnosis to nCPAP were evaluated. All values are reported as means +/- SD. PATIENTS: Thirty-five subjects with newly diagnosed OSAS (8 women and 27 men, mean age: 54.3 +/- 10.6 years, apnea-hypopnea index (AHI) 58.1 +/- 14.0 h(-1)). INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Both treatments were used properly and induced similar decreases in the AHI (7.6 +/- 6.9 vs. 10.4 +/ -12.5 h(-1) for auto-nCPAP and conventional nCPAP, respectively; NS) and Epworth Sleepiness score (from 15.5 +/- 4.7 to 7.5 +/- 3.4 vs. 14.7 +/- 3.9 to 7.6 +/- 3.4 for auto-nCPAP and conventional nCPAP, respectively; NS). With auto-nCPAP initiated at home, the time from diagnosis to final adjustment of nCPAP was shorter (16.3 +/- 5.0 vs. 47.2 +/- 46.5 days with conventional nCPAP, P < 0.02) and the cost was lower (1,263 +/- 352 vs. 1720+/-455 E, respectively; P < 0.05). CONCLUSIONS: Treatment of OSAS with auto-nCPAP initiated at home is effective and reliable and reduces the time from diagnosis to therapy and the cost of treatment.

The impact of split-night polysomnography for diagnosis and positive pressure therapy titration on treatment acceptance and adherence in sleep apnea/hypopnea.

STUDY OBJECTIVES: The time and resource intensive nature of the traditional two-night paradigm for diagnosing and titrating positive pressure therapy for Obstructive Sleep Apnea/Hypopnea (OSA/H) contributes to patient care cost and limitation of service availability. Although split night polysomography (PSG(SN)) algorithms can establish a diagnosis of OSA/H and establish a positive pressure prescription for many patients, there has been only limited evidence that this strategy does not impair acceptance and adherence to treatment. The objective of this study was to test the null hypothesis that PSG(SN) does not adversely impact acceptance and adherence to positive pressure therapy for OSA/H compared with a standard two-night PSG strategy (PSG(TN)). DESIGN: Retrospective case-controlled study. SETTING: University-based sleep disorders program PATIENTS: Both PSG(SN) and PSG(TN) (control) patients were selected on the basis of having an initial medical/sleep evaluation by a full-time physician member of the University of Pittsburgh Sleep Disorders Program, must not have had prior diagnostic PSG or treatment for sleep-disordered breathing, and must have been followed by the Sleep Program team. Selection of PSG(SN) patients required the ability to be matched with a control patient. Both groups underwent evaluation during the same time period. Of 146 patients who underwent PSG(SN) between October 1995 and September 1997, 51 had their initial evaluation and subsequent follow-up by physician-staff members of our Program. Of these, 15 were excluded from analysis because of a previous diagnostic PSG's or prior OSA/H therapy. Also, matches were unavailable for 5 patients. Seven patients refusal to use positive pressure at home and were not available for assessment of adherence, but were included in analysis of therapeutic acceptance. Thus, analysis of the impact of PSG(SN) on adherence to positive pressure therapy was based on a data set of 24 patients in whom a PSG(SN) was performed and 24 patients who had PSG(TN). The two groups were matched for age, Apnea+Hypopnea Index (AHI) and gender. MEASUREMENT AND RESULTS: There were no significant differences between the PSG(SN) and PSG(TN) groups with respect to age, body mass index (BMI), Desaturation Event Frequency (DEF), Arousal Index (ArI) or the Epworth Sleepiness Score (ESS). The nadir of oxyhemoglobin saturation (SpO2) during sleep was lower in the PSG(TN) than PSG(SN) group (69.3+/-15 vs. 79.8+/-9, mean+/-SD, p=0.012). During positive pressure titration, the time spent at the final pressure which was prescribed for the patients were comparable in both groups (123.4+/-64 vs. 161+/-96 minutes, PSG(SN) and PSG(TN), respectively, p=0.17). Adherence to therapy was objectively assessed by the average daily run-time of the positive pressure device at the first meter-read following initiation of treatment (55.1+/-44 vs. 40.8+/-16 days following home set-up, PSG(SN) and PSG(TN), respectively, p=0.14). Depending whether or not patients with previous exposure to positive pressure therapy were included in the analysis, 84-86% of patients undergoing PSG(SN) accepted therapy. There was no difference between the groups with respect to adherence (5.1+/-4 vs. 4.6+/-3 hours, PSG(SN) and PSG(TN), respectively, p=0.64). CONCLUSIONS: In a population of predominantly moderate-to-severe OSA/H patients, PSG(SN) strategy does not adversely impact on adherence to positive pressure therapy over the first six weeks of treatment. Acceptance of therapy is comparable to that reported in the literature following PSG(TN).

Reducing motor-vehicle collisions, costs, and fatalities by treating obstructive sleep apnea syndrome.

STUDY OBJECTIVES: Drivers suffering from obstructive sleep apnea syndrome (OSAS) have an increased risk for being involved in motor-vehicle collisions. This study estimates, for the first time, the annual OSAS-related collisions, costs, and fatalities in the United States and performs a cost-benefit analysis of treating drivers suffering from OSAS with continuous positive airway pressure (CPAP). DESIGN: The MEDLINE-PubMed database (1980 to 2003) was searched for information on OSAS. A meta-analysis was performed of studies investigating the relationship between collisions and OSAS. Data from the National Safety Council were used to estimate OSAS-related collisions, costs, and fatalities and their reduction with treatment. Next, the annual cost of treating OSAS with CPAP was calculated. Finally, multiple 1-way sensitivity analyses were performed. SETTING: N/A. PATIENTS OR PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: More than 800,000 drivers were involved in OSAS-related motor-vehicle collisions in the year 2000. These collisions cost 15.9 billion dollars and 1,400 lives in the year 2000. In the United States, treating all drivers suffering from OSAS with CPAP would cost 3.18 billion dollars, save 11.1 billion dollars in collision costs, and save 980 lives annually. CONCLUSION: Annually, a small but significant portion of motor-vehicle collisions, costs, and deaths are related to OSAS. With CPAP treatment, most of these collisions, costs, and deaths can be prevented. Treatment of OSAS benefits both the patient and the public.

Management of obstructive sleep apnea syndrome in the home. The role of portable sleep apnea recording.

Unattended four-channel sleep apnea recording has been shown to be an accurate tool in the diagnosis of moderate to severe obstructive sleep apnea. We selected 11 patients with severe obstructive sleep apnea who had an apnea-hypopnea index (AHI) determined by unattended sleep apnea recording. The mean AHI was 41 (SD, 17.5). We began nasal continuous positive airway pressure (NCPAP) at home empirically with 5 cm to 7.5 cm of pressure for several nights. We then adjusted the level of NCPAP after telephone interview with the patients and their significant others. The level of NCPAP was increased by 2.5-cm increments until the patients reported cessation of snoring and symptom improvement. The mean NCPAP was 8.0 cm (SD, 1.4). We repeated the overnight sleep apnea recording while on NCPAP in all patients at home to determine their response to therapy. All 11 patients had documented return of their AHI to normal (mean AHI, 2.4; SD, 1.6). Statistically significant improvement was noted in the number of obstructive apneas, hypopneas, total respiratory events, and the AHI. Follow-up data confirmed that patients had improvement in their symptoms and remained compliant with therapy (mean follow-up = 18 months; SD, 10.2). No serious complications were encountered when NCPAP was introduced in an unattended setting. We were able to diagnose and treat these patients in an entirely outpatient setting.

Financial implications of noninvasive positive pressure ventilation (NPPV).

Noninvasive positive pressure ventilation (NPPV) is effective in the treatment of acute and chronic respiratory failure. However, the costs and financial balance between costs and diagnosis-related group (DRG) reimbursement for patients with moderate to severe respiratory failure treated with NPPV are unknown. We examined the costs and DRG reimbursement for 27 patients receiving Medicare referred with moderately severe respiratory failure for NPPV to the ventilator rehabilitation unit (VRU) at Temple University Hospital. This unit is one of four Health Care Financing Administration chronic ventilator-dependent demonstration sites that evaluates patients for NPPV, instructs them in home NPPV use, emphasizes rehabilitation, and uses strict cost accounting methods. Nineteen patients were treated with NPPV in the ICU and then referred to the VRU, and 8 patients were directly admitted for NPPV to the VRU. Patients were (mean +/- SE) 69 +/- 9 years age, 14 had severe COPD, and 13 had various restrictive disorders. All were hypercapneic at the time of hospital admission (restrictive 60 +/- 15; obstructive 67 +/- 3 mm Hg, PaCO2) with impaired lung mechanics and limited functional status. Patients averaged 8 +/- 15 days in the ICU, or 8 +/- 4.7 days on the medical floor prior to VRU transfer. The VRU length of stay averaged 20 +/- 18 days, for a total length of stay of 29 +/- 21 days. After implementation of NPPV, all patients had an improvement in gas exchange while spontaneously breathing and functional status that was maintained in follow-up. At 1 and 2 years of follow-up, 74% and 63% of patients were alive, respectively. Eleven patients were admitted with DRG 475 (respiratory system diagnosis with ventilator support); however, 16 of 27 patients were admitted across five different non-475 DRG codes with reimbursement rates ranging from $2,673 to $4,215. After DRG and outlier reimbursement, a total deficit of $261,948 remained (average deficit $9,701 per patient). However, individual patient deficits ranged from $1,113 to $32,892. Eighty-two percent of patients treated with NPPV incurred substantial financial losses that were underreimbursed across all assigned DRGs, including DRG 475, the highest-weighted DRG. We conclude that patients with moderate to severe respiratory failure receiving NPPV demonstrate an improvement in functional status and gas exchange that is maintained in follow-up. In addition, patients treated with NPPV incur high costs that are currently underreimbursed by the present DRG system. Newer DRG payment scales that recognize NPPV as specific treatment should be implemented.

Reengineering respiratory support following extubation: avoidance of critical care unit costs.

STUDY OBJECTIVE: We prospectively investigated alternative clinical practice strategies for critically ill trauma patients following extubation to evaluate the cost-effectiveness of these maneuvers. The primary change was elimination of the routine use of postextubation supplemental oxygen, with concurrent utilization of noninvasive positive pressure ventilatory support (NPPV) to manage occurrences of postextubation hypoxemia. DESIGN: Prospective, consecutive accrual of patients undergoing extubation. SETTING: Trauma ICU in a university hospital. INTERVENTIONS AND MEASUREMENTS: All patients received mechanical ventilation using pressure support ventilation (PSV) with continuous positive airway pressure (CPAP) as the primary mode. The patients were extubated to room air following a 20-min preextubation trial of 5 cm H(2)O CPAP at FIO(2) of 0.21, and demonstrating a spontaneous respiratory rate /= 7.30, PaCO(2) /= 50 mm Hg. The subgroup of patients who became hypoxemic (pulse oximetric saturation < 88%) within 24 h of extubation were treated with NPPV for up to 48 h duration. Patients who failed NPPV were reintubated. Four hundred fifty-one (84%) patients were successfully extubated to room air. Seventy-two patients (13%) became hypoxemic within 24 h, and NPPV was administered. Fifty-two patients (72% of those who were hypoxemic) responded to NPPV, while 20 patients failed to respond to therapy, were reintubated, and received mechanical ventilation for a mean of 4 days. Thirteen additional patients (2%) were reintubated for reasons other than hypoxemia. The overall reintubation rate for the group (n = 536) was 6.2%; for the postextubation hypoxemic group who failed NPPV, the reintubation rate was 3.7%. The elimination of routine supplemental oxygen via nasal cannula following extubation resulted in a potential direct cost avoidance of $50,006.88 for 451 patient days. Moreover, the 52 patients who were spared reintubation and mechanical ventilation provided an additional potential cost avoidance of $19,740.24 in unused ventilator days per patient. CONCLUSION: Eliminating the routine use of supplemental oxygen and employing NPPV as a method to prevent reintubation can facilitate a more aggressive, cost-effective strategy for the management of the trauma ICU patient who has been extubated.

Annual review of patients with sleep apnea/hypopnea syndrome--a pragmatic randomised trial of nurse home visit versus consultant clinic review.

BACKGROUND: This pragmatic randomised, controlled trial investigated annual review of patients with sleep apnea/hypopnea syndrome (SAHS). Clinical outcomes and costs were compared for consultant clinic review versus specialist nurse home visit. METHOD: One hundred and seventy-four patients were randomised to annual review by consultant clinic appointment or by specialist nurse home visit. SAHS symptoms, Epworth score, hospital anxiety and depression scale (HADS), Short Form-36 (SF-36) and hours of use of constant positive airway pressure (CPAP) were measured before and 3 months after review. The costs and patient preference for review were determined. RESULTS: After review, both groups significantly increased CPAP use (mean (SD) increase: nurse, 0.66 (1.71) h; consultant, 0.45 (1.69) h) and reduced symptom scores (nurse, -2 (7); consultant, -3 (9)), compared to baseline. There were no differences between groups in these improvements, or in HADS or SF-36 scores. Average duration of a nurse home visit, excluding travel time, was 26 (6) min. Total NHS cost per visit was 52.26 UK pounds (49.85) ($83.62 (79.76)), of which 6.57 UK pounds (1.43) ($10.51 (2.29)) reflected time spent with the patient and the remainder was travel cost. Average duration of consultant review was 10 (6) min, total NHS cost 6.21 UK pounds (3.99) ($9.94 (6.38)). However, the cost to the patient of attending the clinic was 23.63 UK pounds (23.21) ($37.81 (37.13)). Patient preference for review was nurse 16%, consultant 19%, and no preference 65%. CONCLUSION: Following annual review, use of CPAP increased and symptoms improved. Outcomes were similar for consultant and nurse led review. Home visits were expensive for the healthcare provider, whereas clinic attendance incurred substantial costs to the patient. The majority of patients would accept nurse review for their sleep apnea management.

Noninvasive positive-pressure ventilation in patients with acute respiratory failure.

This article provides a systematic review of the literature on the application of noninvasive ventilation in various forms of hypercapnic and hypoxemic respiratory failures. A description of the underlying pathophysiology is followed by a review of physiologic data explaining the mechanisms of action of noninvasive ventilation. A critical review of clinical studies is presented with specific suggestions. The methodology of correctly implementing and monitoring noninvasive ventilation in patients with acute respiratory failure, critical to success, is detailed.

Noninvasive ventilation in neuromuscular disease.

The treatment of respiratory failure in patients who have NMD continues to be an evolving process. Negative-pressure ventilation, once prominent in the 1940s and 1950s, gave way to intermittent positive-pressure ventilation with tracheostomy or endotracheal tubes in the 1960s. Now there is a resurgence of noninvasive ventilation, brought about by innovative modes of positive pressure delivered through nasal and facial masks. Although frequently relegated to second-line choices, negative-pressure devices still offer a practical treatment alternative as patient preference still plays a role in selecting a proper mode of ventilation. Studies have shown that noninvasive ventilation can prevent or reverse respiratory failure and improve quality of life and longevity. Despite the seemingly widespread acceptance of noninvasive ventilation in the treatment of respiratory failure, physicians still appear reluctant to use ventilatory assistance in the neuromuscular arena. In 1985, a survey found that respiratory support systems were utilized routinely in only 33% of the 132 responding Muscular Dystrophy Association (MDA) clinics. Bach recently surveyed 273 MDA clinic directors and co-directors from 167 clinics, to evaluate their current use of mechanical ventilation. Ventilatory assistance was recommended and used electively in only 43 (26%) of the 167 clinics. Furthermore, it was the policy in 68 of the clinics to discourage the use of mechanical ventilation. Even more importantly, only 2 physicians who discouraged the use of mechanical ventilation were familiar with the newest noninvasive methods of ventilatory support. Sadly, although our methodologies in the treatment of respiratory failure continue to improve, physician practice has lagged behind. Physicians who treat patients who have NMD need to become cognizant of these new techniques and incorporate them into their present therapeutic armamentarium.