Survey of non-invasive ventilation (NIPPV) in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) in the UK

Safety and efficacy of noninvasive ventilation for acute respiratory failure in general medical ward: a prospective cohort study

Background

Noninvasive ventilation (NIV) is recommended for use in patients with acute respiratory failure of various etiologies. However, we do not know whether the use of NIV in general medical wards is safe and effective. This study aimed to evaluate the safety and efficacy of using NIV and factors associated with NIV failure in general medical wards.

Methods

A prospective cohort study was conducted in general medical wards of the University Hospital. Adult patients with acute respiratory failure treated with NIV were enrolled. The subjects were managed by a multidisciplinary care team that was well trained in the NIV device. The primary outcome was the rate of NIV failure at 48 hours. Secondary outcomes included hospital mortality and factors associated with NIV failure.

Results

A total of 86 patients were enrolled. The mean age was 70±17 years old. The Acute Physiology and Chronic Health Evaluation (APACHE) III and the Sequential Organ Failure Assessment (SOFA) scores were 56±17 and 4±3, respectively. The most common indication of NIV use was cardiogenic pulmonary edema (34.9%). The rate of NIV failure at 48 hours and hospital mortality were 20.9% and 12.8%, respectively. The SOFA score was associated with failure of NIV at 48 hours [odds ratio (OR) 1.48, 95% confidence interval (CI): 1.16-1.89; P=0.002].

Conclusions

NIV was safe and effective on general medical wards. Cardiogenic pulmonary edema was the most common indication for the application of NIV. The SOFA score was associated with the failure of NIV at 48 hours.

Hospital Variation in Non-Invasive Ventilation Use for Acute Respiratory Failure Due to COPD Exacerbation

Background

Non-invasive mechanical ventilation (NIV) use in patients admitted with acute respiratory failure due to COPD exacerbations (AECOPDs) varies significantly between hospitals. However, previous literature did not account for patients’ illness severity. Our objective was to examine the variation in risk-standardized NIV use after adjusting for illness severity.

Methods

We retrospectively analyzed AECOPD hospitalizations from 2011 to 2017 at 106 acute-care Veterans Health Administration (VA) hospitals in the USA. We stratified hospitals based on the percentage of NIV use among patients who received ventilation support within the first 24 hours of admission into quartiles, and compared patient characteristics. We calculated the risk-standardized NIV % using hierarchical models adjusting for comorbidities and severity of illness. We then stratified the hospitals by risk-standardized NIV % into quartiles and compared hospital characteristics between quartiles. We also compared the risk-standardized NIV % between rural and urban hospitals.

Results

In 42,048 admissions for AECOPD over 6 years, the median risk-standardized initial NIV % was 57.3% (interquartile interval [IQI]=41.9–64.4%). Hospitals in the highest risk-standardized NIV % quartiles cared for more rural patients, used invasive ventilators less frequently, and had longer length of hospital stay, but had no difference in mortality relative to the hospitals in the lowest quartiles. The risk-standardized NIV % was 65.3% (IQI=34.2–84.2%) in rural and 55.1% (IQI=10.8–86.6%) in urban hospitals (p=0.047), but hospital mortality did not differ between the two groups.

Conclusion

NIV use varied significantly across hospitals, with rural hospitals having higher risk-standardized NIV % rates than urban hospitals. Further research should investigate the exact mechanism of variation in NIV use between rural and urban hospitals.

Noninvasive ventilation utilization in the Kingdom of Saudi Arabia: Results of a national survey

INTRODUCTION

Noninvasive ventilation (NIV) has been extensively used globally and is often administered as the first-line treatment. Currently, data regarding the utilization of NIV in the Kingdom of Saudi Arabia (KSA) is scarce. The present study aimed to assess and quantify the utilization of NIV in clinical practice across the KSA and investigate obstacles that may cause NIV underutilization.

METHODS

A web-based survey composed of a 31-item, self-administered questionnaire was developed and validated. The questionnaire was designed to obtain general information about each hospital, availability of NIV practice, use of NIV, and obstacles that can hinder NIV use in clinical settings; the survey was sent to senior respiratory therapists (RTs) of 76 hospitals. Descriptive statistics were used to analyze the data.

RESULTS

Sixty-one hospitals (80.3%) responded to the survey (47 governmental and 14 private). NIV was available in all hospitals and all the Intensive Care Units. The majority of RTs (85%) reported having a good experience with NIV, with a confidence rate of 60%; however, only 22% of the RTs had received formal training. Although NIV setup was the sole responsibility of RTs, only 69% participated in NIV management. Moreover, 72% of hospitals had an NIV setup protocol in place. However, 50% of them lacked a protocol for NIV failure. NIV protocols for specific indications were present in 64% of the hospitals: 47.2% for monitoring and 42% for weaning. The perceived efficiency of NIV practice was low in the medical wards, with a <49% success rate in 39% of the hospitals. Shortage of staff and lack of formal training were the most common reasons for NIV underutilization.

CONCLUSION

The efficiency of NIV in the KSA was low. The RTs expressed moderate confidence in administering NIV. Lack of appropriate exposure and formal training could have negative impacts on NIV practice.

Survey on accessibility and real-life application of noninvasive ventilation

Noninvasive mechanical ventilation (NIV) is an accepted method of respiratory failure treatment; however, at present, little is known about the global factors limiting NIV application. A survey designed to determine NIV accessibility and limiting factors in world economies and regions was developed. The questionnaire was sent to members of the European Respiratory Society (ERS) Respiratory Intensive Care Assembly and all ERS National Delegates. Replies to the survey were collected from 161 respondents from 46 countries. NIV was found to be provided most frequently by pulmonologists and intensivists. In high-income economies (HIEs), NIV reimbursement in chronic respiratory failure treatment was found to be independent of the underlying disease and supplementary insurance (p<0.0001), whereas in upper-middle-income economies (UMIEs) it was found to be dependent on the underlying disease (p<0.0001). In chronic respiratory failure, NIV was not reimbursed in lower-middle-income economies (LMIEs) (p<0.0001). In LMIEs and UMIEs, the lack of financial resources was the main limiting factor in acute (p=0.007) and chronic respiratory failure (p<0.0001). In the income-level-based assessment, financing was recognised as relevant in LMIEs and UMIEs (p<0.0001), equipment in LMIEs and UMIEs (p=0.03), medical staff in all economies (p=0.02), and legal regulations in LMIEs (p=0.0005). It was confirmed that NIV in acute and chronic respiratory failure is reimbursed based on government regulations in UMIEs and HIEs (p<0.0001), and is not reimbursed and probably will not be reimbursed in the near future in LMIEs (p<0.0001). We conclude that financial constraints are still considered a major limiting factor for NIV use.

Epidemiology of NIV for Acute Respiratory Failure in COPD Patients: Results from the International Surveys vs. the "Real World"

Non-invasive ventilation (NIV) has been recommended as the  first-line ventilation modality for acute respiratory failure (ARF) due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD) based on strong evidence. However, everyday clinical practice may differ from findings of multiple randomized controlled trials. Physicians and respiratory therapists involved in NIV management have been queried about its utilization and effectiveness. In addition to these estimates, cohort studies and analysis of large inpatient dataset of patients with AECOPD and ARF managed with NIV have been extensively published over the last two decades. This review summarizes the perception of medical staff vs. the "real life" data about NIV use for ARF in AECOPD patients.

Lights and shadows of non-invasive mechanical ventilation for chronic obstructive pulmonary disease (COPD) exacerbations

Despite the overwhelming evidence justifying the use of non-invasive ventilation (NIV) for providing ventilatory support in chronic obstructive pulmonary disease (COPD) exacerbations, recent studies demonstrated that its application in real-life settings remains suboptimal. European clinical audits have shown that 1) NIV is not invariably available, 2) its availability depends on countries and hospital sizes, and 3) numerous centers declare their inability to provide NIV to all of the eligible patients presenting throughout the year. Even with an established indication, the use of NIV in acute respiratory failure due to COPD exacerbations faces important challenges. First, the location and personnel using NIV should be carefully selected. Second, the use of NIV is not straightforward despite the availability of technologically advanced ventilators. Third, NIV therapy of critically ill patients requires a thorough knowledge of both respiratory physiology and existing ventilatory devices. Accordingly, an optimal team-training experience, the careful selection of patients, and special attention to the selection of devices are critical for optimizing NIV outcomes. Additionally, when applied, NIV should be closely monitored, and endotracheal intubation should be promptly available in the case of failure. Another topic that merits careful consideration is the use of NIV in the elderly. This patient population is particularly fragile, with several physiological and social characteristics requiring specific attention in relation to NIV. Several other novel indications should also be critically examined, including the use of NIV during fiberoptic bronchoscopy or transesophageal echocardiography, as well as in interventional cardiology and pulmonology. The present narrative review aims to provide updated information on the use of NIV in acute settings to improve the clinical outcomes of patients hospitalized for COPD exacerbations.

The successful treatment of hypercapnic respiratory failure with oral modafinil

Hypercapnic respiratory failure is common in advanced chronic obstructive pulmonary disease and is usually treated by nasal ventilation. Not all patients requiring such ventilation can tolerate it, with anxiety and phobia influencing their reaction, along with treatment failure. We report the case histories of six patients with hypercapnic respiratory failure who were at risk of death due to refusal of nasal ventilation or its failure despite ongoing treatment. We report their improvement with oral modafinil 200 mg tablets used as a respiratory stimulant, which led to discharge, improved arterial blood gases, and offset further admissions with hypercapnic respiratory failure. This drug is licensed for narcolepsy and is said to stimulate the respiratory system via the central nervous system. Its use in respiratory failure is an unlicensed indication, and there are no case reports or studies of such use in the literature. Its respiratory stimulant effects appear better than those with protriptyline, which was a drug previously used until its production was discontinued. Our findings suggest that a study of modafinil in hypercapnic respiratory failure would be warranted, especially for patients with treatment failure or intolerance to nasal ventilation. This may offer a way of shortening hospital stay, improving outcome and quality of life, and reducing death and readmissions.

New modalities for non-invasive ventilation

There is now substantial evidence supporting the use of non-invasive ventilation in acute hypercpanic exacerbations of chronic respiratory failure, and early trials show nocturnal ventilatory support may benefit chronic heart failure patients with sleep disordered breathing. Attention is now being focused on innovative modes which adapt respiratory support to the user's ventilatory pattern, eg adaptive service ventilation and assured volume delivery 'intelligent' ventilation.

Outcomes of noninvasive ventilation for acute exacerbations of chronic obstructive pulmonary disease in the United States, 1998-2008

RATIONALE

The patterns and outcomes of noninvasive, positive-pressure ventilation (NIPPV) use in patients hospitalized for acute exacerbations of chronic obstructive pulmonary disease (COPD) nationwide are unknown.

OBJECTIVES

To determine the prevalence and trends of noninvasive ventilation for acute COPD.

METHODS

We used data from the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample to assess the pattern and outcomes of NIPPV use for acute exacerbations of COPD from 1998 to 2008.

MEASUREMENTS AND MAIN RESULTS

An estimated 7,511,267 admissions for acute exacerbations occurred from 1998 to 2008. There was a 462% increase in NIPPV use (from 1.0 to 4.5% of all admissions) and a 42% decline in invasive mechanical ventilation (IMV) use (from 6.0 to 3.5% of all admissions) during these years. This was accompanied by an increase in the size of a small cohort of patients requiring transition from NIPPV to IMV. In-hospital mortality in this group appeared to be worsening over time. By 2008, these patients had a high mortality rate (29.3%), which represented 61% higher odds of death compared with patients directly placed on IMV (95% confidence interval, 24-109%) and 677% greater odds of death compared with patients treated with NIPPV alone (95% confidence interval, 475-948%). With the exception of patients transitioned from NIPPV to IMV, in-hospital outcomes were favorable and improved steadily year by year.

CONCLUSIONS

The use of NIPPV has increased significantly over time among patients hospitalized for acute exacerbations of COPD, whereas the need for intubation and in-hospital mortality has declined. However, the rising mortality rate in a small but expanding group of patients requiring invasive mechanical ventilation after treatment with noninvasive ventilation needs further investigation.

Noninvasive ventilation in adults with acute respiratory distress: a primer for the clinician

Noninvasive ventilation (NIV) has become an integral part of critical care management. Despite > 2 decades of experience, it is relatively underused, with general utilization reported as a little over 10% in a recent international survey. Lack of training, knowledge, equipment, and experience with NIV may account for its slow adoption. Patient selection, staff training and experience, and prompt recognition of ineffective NIV are important components to successful application of NIV. Noninvasive ventilation does have a learning curve that may be steep for some institutions but must be mastered if the procedure is to become a successful institutional component of care. Patients with acute respiratory failure due to chronic obstructive pulmonary disease or congestive heart failure are ideal candidates for NIV, and optimal efficacy in associated conditions is often linked to these 2 conditions. Technical issues and written guidelines are addressed, including details of an adequate trial of therapy as well as criteria for intubation. Attention to these elements should increase the success rate of NIV, which in turn should increase its general use.

Noninvasive ventilation: a survey of practice patterns of its use in India

Background and Aims:

To understand the practice patterns of noninvasive ventilation (NIV) use by Indian physicians.

Subjects and Methods:

Around three thousand physicians from all over India were mailed a questionnaire that could capture the practice patterns of NIV use.

Results:

Completed responses were received from 648 physicians (21.6%). Majority (n = 469, 72.4%, age 40 ± 9 years, M:F 409:60) use NIV in their clinical practice. NIV was most exclusively being used in the ICU setting (68.4%) and the commonest indication for its use was chronic obstructive pulmonary disease (COPD) (71.4%). A significant number did not report use of a conventional ventilator for NIV support (62%). Oronasal mask was the overwhelming favorite among the sampled physicians (68.2%). In most of the cases, the treating physician initiated NIV (60.8%) and a baseline blood gas analysis was performed in only 71.1% of the cases (315/443). Nasal bridge pressure sores was the commonest complication (64.2%).

Conclusions:

NIV is being widely used in clinical practice in India for various indications. COPD is the most common indication for its deployment. There seems to be a marked variability in the patterns relating to actual deployment of NIV, including the site of initiation, protocols for initiation followed, and monitoring of patients.

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.

Non-invasive ventilation in exacerbations of COPD

Randomized controlled trials have confirmed the evidence and helped to define when and where non invasive mechanical ventilation (NIV) should be the first line treatment of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Noninvasive ventilation has its best indication in moderate-to-severe respiratory acidosis in patients with AECOPD. For this indication, studies conducted in ICU, in wards and in accident and emergency departments confirmed its effectiveness in preventing endotracheal intubation and reducing mortality. The skill of the health care team promotes proper NIV utilization and improves the patient outcome. Patients with severe acidosis or with altered levels of consciousness due to hypercapnic acute respiratory failure are exposed to high risk of NIV failure. In these patients a NIV trial may be attempted in closely monitored clinical settings where prompt endotracheal intubation may be assured.

Geographic variation in chronic obstructive pulmonary disease exacerbation rates

BACKGROUND

Exacerbations are important disease events for patients with chronic obstructive pulmonary disease (COPD) as they are relatively frequent, result in significant resource use and can indicate worsening disease. Little is known about variation in COPD exacerbation rates across a health system in various geographic regions.

OBJECTIVE

To compare COPD exacerbation rates by regional service networks called Veterans Integrated Service Network (VISN) in the Veterans Health Administration (VA) system.

DESIGN

Retrospective, observational study.

SUBJECTS

Patients with a COPD diagnosis from October 1999 to September 2000 with follow-up to September 2002.

MEASUREMENTS

Acute exacerbations of COPD during the baseline and follow-up periods.

RESULTS

A total of 198,981 patients were identified. Average exacerbation rate at baseline was 0.503 events per person per year. In the follow-up period, there were 187,686 exacerbations experienced by 87,494 persons (44.0% of cohort). During follow-up, the average adjusted exacerbation rate was 0.589 per person per year and varied from 0.335 (95% CI, 0.328-0.342) in VISN 1 to 0.749 (95% CI, 0.735-0.0.763) in VISN 9. Using the median rate of exacerbation during the baseline period as the referent, 9 VISNs had lower adjusted rate ratios and 12 VISNs had higher adjusted rate ratios in the follow-up period.

CONCLUSIONS

Geographic variation in the VA VISN system supports evidence that the medical care system including provider factors, and less so patient factors, affect COPD exacerbations. Understanding the reasons underlying this variation in COPD exacerbation rates may lead to improvements in future care and outcomes.

Noninvasive ventilation for critical care

Noninvasive ventilation (NIV), the provision of ventilatory assistance without an artificial airway, has emerged as an important ventilatory modality in critical care. This has been fueled by evidence demonstrating improved outcomes in patients with respiratory failure due to COPD exacerbations, acute cardiogenic pulmonary edema, or immunocompromised states, and when NIV is used to facilitate extubation in COPD patients with failed spontaneous breathing trials. Numerous other applications are supported by weaker evidence. A trial of NIV is justified in patients with acute respiratory failure due to asthma exacerbations and postoperative states, extubation failure, hypoxemic respiratory failure, or a do-not-intubate status. Patients must be carefully selected according to available guidelines and clinical judgment, taking into account risk factors for NIV failure. Patients begun on NIV should be monitored closely in an ICU or other suitable setting until adequately stabilized, paying attention not only to vital signs and gas exchange, but also to comfort and tolerance. Patients not having a favorable initial response to NIV should be considered for intubation without delay. NIV is currently used in only a select minority of patients with acute respiratory failure, but with technical advances and new evidence on its proper application, this role is likely to further expand.

Patterns of blood glucose monitoring in relation to glycemic control among patients with type 2 diabetes in the UK

AIMS

The objectives of this study were to compare patterns of blood glucose monitoring among patients with type 2 diabetes initiating therapy with insulin or oral medication and to examine the relationship between the quantity of prescribed monitoring strips and glycemic control.

METHODS

Data were obtained from the UK General Practice Research Database. Patients were eligible if they were identified as having type 2 diabetes, initiated therapy with insulin or an oral agent, and had 12-month postinitiation data. Differences in patient characteristics and number of test strips prescribed between the insulin (n=347) and oral cohorts (n=2436) were examined. Multivariate regressions examined the relationship between quantity of monitoring and glycemic control for a subset of patients (insulin, n=245; oral, n=1795) with available glycosylated hemoglobin (HbA1c) data.

RESULTS

During the 12-month postinitiation period, patients using insulin were prescribed approximately twice as many test strips compared with those patients using oral medication (149 vs. 78, P<.0001). Multivariate regressions revealed that individuals who initiated insulin therapy and were prescribed enough test strips to test at least once per day in the 6 months prior to the HbA1c test date had, on average, a 0.65% lower HbA1c value (P=.02) compared with individuals who were prescribed fewer test strips.

CONCLUSIONS

Results indicate significant differences in the prescription of blood glucose monitoring strips, with patients initiated on insulin prescribed almost twice as many test strips compared with patients initiated on orals. The greater number of blood glucose test strips prescribed was associated with lower HbA1c values for insulin patients.

Availability and use of noninvasive ventilation in the intensive care units of public, private and teaching hospitals in the greater metropolitan area of São Paulo, Brazil

OBJECTIVE

To determine the availability of noninvasive positive-pressure ventilation equipment, as well as the level of expertise and familiarity of physicians, nurses and physiotherapists with noninvasive positive-pressure ventilation in the intensive care units of public, private and teaching hospitals in the greater metropolitan area of São Paulo, Brazil.

METHODS

On-site administration of questionnaires.

RESULTS

Noninvasive positive-pressure ventilation equipment was widely available and was more commonly found in private hospitals than in teaching hospitals. Such equipment was least available in public hospitals, in which the predominant method was the use of mechanical ventilators designed for invasive ventilation and adapted to noninvasive positive-pressure ventilation. In private hospitals, continuous flow ventilators were more common, whereas, in teaching hospitals, ventilators specifically designed for noninvasive ventilation were typically employed. All physiotherapists felt themselves capable of initiating noninvasive positive pressure ventilation, compared with 72.6% of physicians and 33.3% of nurses. Physicians and physiotherapists presented high percentages of correct answers when asked about the indications and contraindications for the use of noninvasive positive-pressure ventilation. Over a one year period, more physiotherapists read articles about noninvasive positive-pressure ventilation and participated in related classes than did physicians, who in turn did so more than did nurses.

CONCLUSION

Noninvasive positive-pressure ventilation equipment is widely available in the greater metropolitan area of São Paulo, although differences exist among public, private and teaching hospitals in terms of the type of equipment used. Physicians and physiotherapists exhibited considerable knowledge regarding the indications and contraindications for the use of noninvasive positive-pressure ventilation. More physiotherapists felt themselves able to initiate noninvasive positive-pressure ventilation, and their knowledge of the subject was more current than was that of physicians or nurses.

Management of acute ventilatory failure

Acute ventilatory failure is a challenging yet increasingly common medical emergency reflecting the growing burden of respiratory disease. It is not a diagnosis in itself but the end result of a diversity of disease processes culminating in arterial hypoxaemia and hypercapnia. This review focuses on key management issues including giving appropriate oxygen therapy, treatment of the underlying aetiology as well as any precipitant factors and provision of assisted ventilation if required. Ventilatory assistance can be provided both invasively and non-invasively and the indications for either or both forms of assisted ventilation are discussed. Further emphasis is needed regarding advanced directives of care and clinicians should be aware of ethical issues regarding assisted ventilation.

Utilization of noninvasive ventilation in acute care hospitals: a regional survey

PURPOSES

Little information is available on the utilization of noninvasive positive-pressure ventilation (NPPV) in the United States. Accordingly, we performed a survey on the use of NPPV at acute care hospitals in a region of the United States to determine variations in utilization and between hospitals, the reasons for lower rates of utilization, and the techniques used for application.

METHODS

Using survey methodology, we developed a questionnaire consisting of 19 questions and distributed it by mail to directors of respiratory care at all 82 acute care hospitals in Massachusetts and Rhode Island. Nonresponders were contacted by phone to complete the survey. Responses were analyzed using standard statistics, including t tests and Mann-Whitney U tests where appropriate.

RESULTS

We obtained responses from 71 of the 82 hospitals (88%). The overall utilization rate for NPPV was 20% of ventilator starts, but we found enormous variation in the estimated utilization rates among different hospitals, from none to > 50%. The top two reasons given for lower utilization rates were a lack of physician knowledge and inadequate equipment. In the 19 hospitals that provided detailed information, COPD and congestive heart failure constituted 82% of the diagnoses of patients receiving NPPV, but NPPV was still used in only 33% of patients with these diagnoses receiving any form of mechanical ventilation.

CONCLUSIONS

The utilization rates for NPPV vary enormously among different acute care hospitals within the same region. The perceived reasons for lower utilization rates include lack of physician knowledge, insufficient respiratory therapist training, and inadequate equipment. Educational programs directed at individual institutions may be useful to enhance utilization rates.

Physiotherapy involvement in non-invasive ventilation hospital services: a British Isles survey

The aim of this study was to assess the involvement of physiotherapists in the delivery of non-invasive ventilation (NIV) services in the British Isles. A postal questionnaire was sent to all senior physiotherapists in hospitals providing specialist respiratory medicine. The response rate was 88% (269/305). Physiotherapists were involved in managing patients using NIV in 212/233 hospitals that used NIV. The majority of physiotherapists, 97% (206/212), were involved in treating patients on NIV. Physiotherapists assessed patients for NIV in 68% (145/212) of hospitals and were involved in setting up patients on NIV in 46% (97/212) of hospitals. There were no major differences between countries, within the British Isles, in the level of involvement of Physiotherapists in the management of patients on NIV. Physiotherapists need to develop specialist skills with regard to assessment and setting up patients on NIV if they want to expand their role in the management of patients on NIV.

Non-invasive ventilation in surgical patients in a district general hospital

We have retrospectively audited the use of non-invasive ventilation (NIV) in surgical patients. We analysed the case notes of 38 surgical patients who received NIV over a 9-month period. Twenty-three patients received NIV following emergency surgery, eight after elective surgery, and seven did not have an operation. Co-morbidity was common. The commonest reasons for starting NIV were chest infection, acute respiratory distress syndrome and pulmonary oedema. NIV was often only one aspect of treatment in surgical patients with complex medical problems. With intensive support from the critical care outreach team, NIV can be safely delivered on a surgical ward, and may sometimes prevent intensive care unit admission. Use of NIV on the intensive care unit may obviate the need for tracheal intubation in some patients. In very ill surgical patients with a poor prognosis, NIV was frequently used as the ceiling of respiratory support.

The use of noninvasive ventilation in acute respiratory failure at a tertiary care center

OBJECTIVE

Financial constraints and bed limitations frequently prevent admission of ill patients to a critical care setting. We surveyed the use of treatment with noninvasive ventilation (NIV) in clinical practice by physicians in a tertiary care, university-based teaching hospital and compared our findings with published recommendations for the use of NIV.

METHODS

Data were collected prospectively on all patients with acute respiratory failure (ARF) for whom NIV was ordered over a 5-month period. The respiratory therapy department was responsible for administering NIV on written order by a physician. The respiratory therapist completed a survey form with patient tracking data for each initiation of NIV. The investigators then surveyed the clinical chart for clinical data.

RESULTS

NIV was utilized for the treatment of ARF on 75 occasions during the 5-month period. Fourteen patients (18%) received NIV for a COPD exacerbation, and 61 patients (82%) received it for respiratory failure of other etiologies. NIV was initiated in the emergency department in 32% of patients, in a critical care setting in 27% of patients, in a ward observation unit in 23% of patients, and on a general medical or surgical ward in 18% of patients. Arterial blood gases (ABGs) were measured on 68 occasions prior to the initiation of NIV, and 51 patients had an ABG measurement within the first 6 h of treatment. The mean pH at baseline was 7.29, and 33% of patients had a baseline pH of < 7.25. Seven patients required endotracheal intubation (ETI) [13%], and there were 18 deaths (24%) with patients having do-not-resuscitate orders, accounting for 12 deaths.

CONCLUSION

NIV is commonly used outside of a critical care setting. Our outcomes of ETI and death were similar to those cited in the literature despite less aggressive monitoring of these patients.

Barriers to providing lung-protective ventilation to patients with acute lung injury

OBJECTIVE

No studies have explored the barriers to implementing lung-protective ventilation in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Our objective was to identify barriers to using lung-protective ventilation in patients with ALI/ARDS.

DESIGN

Survey with content analysis of open-ended responses.

SETTING

Medical center.

PARTICIPANTS

Experienced intensive care unit nurses and respiratory therapists network identified through purposive sampling at hospitals from the ARDS Network, a National Institutes of Health-sponsored research consortium.

INTERVENTIONS

Survey.

RESULTS

Fifty-five surveys representing all ten ARDS Network sites were received. Twenty-seven (49%) of the respondents were intensive care unit nurses, 24 (44%) were respiratory therapists, and four did not indicate their profession. Clinicians had used lung-protective ventilation in a median of 20 (interquartile range, 10-50) patients with ALI/ARDS. Respondents identified physician willingness to relinquish control of ventilator, physician recognition of ALI/ARDS, and physician perceptions of patient contraindications to low tidal volumes as important barriers to initiating lung-protective ventilation. Important barriers to continuing patients on lung-protective ventilation were concerns over patient discomfort and tachypnea and concerns over hypercapnia, acidosis, and hypoxemia. Techniques for overcoming barriers were identified including specific ventilator setup recommendations, clinician education, and tools to assess patient discomfort.

CONCLUSIONS

Experienced bedside clinicians perceive important barriers to implementing lung-protective ventilation. Successful strategies to increase use of lung-protective ventilation should target these barriers.

Implementing effective ventilator practice at the bedside

PURPOSE OF REVIEW

New data on the efficacy of low tidal volume ventilation for acute lung injury, noninvasive ventilation for chronic obstructive pulmonary disease exacerbation, weaning from mechanical ventilation, and prevention of ventilator-associated pneumonia provide, for perhaps the first time in respiratory care, compelling evidence for clinicians to change practice. However, experience from every other field in medicine suggests that there will be significant barriers to changing clinical practice at the bedside. Studies on implementation of effective practice in medicine shows that a multifaceted, team-oriented approach incorporating reminders, efficient use of non-physician personnel, protocols, and education is required to change clinical practice. Limited data on current practice of mechanical ventilation suggest that it deviates from recommended practice. Unfortunately, there are no studies exploring community-based implementation of mechanical ventilation guidelines and only a few studies to inform clinicians as to why ventilator practice may be difficult to change. As the evidence base grows for effective critical care practice, so does the responsibility to translate practices that improve outcome from research journals to patients' bedsides. Strategies for doing this are presented in the review.

Assessing the burden of respiratory disease in the UK

This review explores the health and social burden of some of the main respiratory diseases (asthma, chronic obstructive pulmonary disease, cryptogenic fibrosing alveolitis, cystic fibrosis, lung cancer, mesothelioma, obstructive sleep apnoea and tuberculosis) in order to increase awareness of these diseases and highlight areas where improvements in care are required. The overall impact of respiratory diseases in the U.K. in terms of prevalence, mortality, morbidity and economic costs, with particular reference to secondary care has been considered and comparisons made with the rest of Europe where data are available. Respiratory diseases are responsible for a significant proportion of serious morbidity and premature death among the population of the U.K. and they will continue to present a growing challenge; special support is needed to tackle this burden.

Survey of non-invasive ventilation for acute exacerbation of chronic obstructive pulmonary disease patients in emergency departments in Belgium

A study was undertaken to assess the availability and use of non-invasive ventilation (NIV) for the treatment of acute exacerbation of chronic obstructive pulmonary disease (COPD) in emergency departments in Belgium. A questionnaire was sent to the head physicians of 145 emergency departments (EDs) found in the list of the Belgian College of Emergency Physicians (BeCEP). Ninety eight questionnaires were analysed (representing 68% of the questionnaires sent). NIV was used in 49% of the EDs. In the hospitals where NIV was not used, the most important reasons given were no available equipment in 71%, lack of experience with this form of treatment in 32.7%, and more time consuming for physicians and nursing staff in 22.8%. Only 3.8% of the physicians doubted the benefit of NIV treatment. In the hospitals where NIV was used, the patient was watched during the first hour by one nurse only in 19.6%, by one physician in 8.6% and by a nurse and a physician in 54.5%. NIV was used for more than 4 h in 33% of EDs. Pressure-controlled ventilation (with home respirators) was used more often than volume-controlled ventilation.

One year period prevalence study of respiratory acidosis in acute exacerbations of COPD: implications for the provision of non-invasive ventilation and oxygen administration

BACKGROUND

Non-invasive ventilation (NIV) reduces mortality and intubation rates in patients with chronic obstructive pulmonary disease (COPD) admitted to hospital with respiratory acidosis. This study aimed to determine the prevalence of respiratory acidosis in patients admitted with COPD, to draw inferences about oxygen therapy, and to determine the need for NIV services for acute COPD in typical UK hospitals.

METHODS

This one year prospective prevalence study identified patients with COPD aged 45-79 years inclusive who were admitted to Leeds General Infirmary, St James's University, and Killingbeck Hospitals, Leeds between 1 March 1997 and 28 February 1998. The prevalence of respiratory acidosis and the relationship with oxygenation are described. Other outcomes included intensive care use and in hospital mortality. From this data population prevalence estimates were determined for respiratory acidosis, from which the need for NIV in a typical district general hospital was modelled.

RESULTS

983 patients were admitted, 11 of whom required immediate intubation. 20% of the remaining 972 had a respiratory acidosis. Acidosis was associated with subsequent admission to the intensive care unit (ICU): pH<7.25, OR 6.10 (95% confidence interval (CI) 1.19 to 31.11); pH 7.25-7.30, OR 8.73 (95% CI 2.11 to 36.06). pH was inversely correlated with arterial oxygen tension (PaO(2)) in the 47% of patients who were hypercapnic, with a PaO(2) of >10 kPa being associated with acidosis in most hypercapnic patients. 80% remained acidotic after initial treatment, giving an age/sex specific prevalence for England and Wales of 75 (95% CI 61 to 90)/100 000/year for men aged 45-79 years and 57 (95% CI 46 to 69)/100 000/year for women. Modelling the need for NIV for all COPD patients indicates that a typical UK hospital will admit 90 patients per year with acidosis of which 72 will require NIV.

CONCLUSIONS

In patients with acute COPD the PaO(2) should be maintained at 7.3-10 kPa (SaO(2) 85-92%) to avoid the dangers of hypoxia and acidosis. If all COPD patients with a respiratory acidosis (pH<7.35) after initial treatment are offered NIV, a typical UK hospital will treat 72 patients per year.