Noninvasive positive pressure ventilation in acute respiratory failure due to COPD vs other causes: effectiveness and predictors of failure in a respiratory ICU in North India

Effectiveness and Outcomes of Noninvasive Positive Pressure Ventilation in Patients With Acute Exacerbations of Chronic Obstructive Pulmonary Disease

BACKGROUND

Endotracheal intubation and mechanical ventilation in individuals experiencing acute exacerbations of chronic obstructive pulmonary disease (COPD) are associated with several complications. Therefore, utilizing noninvasive positive pressure ventilation (NIPPV) is the suggested initial management for these individuals. The current study was done to assess and compare the clinical and physiological parameters before and after the application of NIPPV and also to evaluate the outcomes of NIPPV.

METHODOLOGY

A prospective observational study was conducted on 50 patients with COPD experiencing acute exacerbations. These patients were treated with NIPPV. Measurements of blood pressure, respiratory rate (RR), heart rate (HR), dyspnea using the modified Borg scale, and arterial blood gas (ABG) parameters (pH, PaCO2, and PaO2) were recorded at baseline, one hour, six hours, 24 hours, and daily until discharge. The study's outcomes included the subjects who successfully underwent NIPPV and failed during NIPPV.

RESULTS

NIPPV effectively reduced the dyspnea score from 7.24 ± 1.58 at baseline to 5.53 ± 1.82 at one hour, 4.11 ± 1.75 at six hours, 2.60 ± 1.03 at 24 hours, and 1.26 ± 0.44 at the time of discharge. Significant improvements were also observed in HR and RR (P < 0.001). When compared to the baseline, the pH level was significantly maintained, PaCO2 was decreased, and PaO2 was increased at various times. Mortality was observed in four patients.

CONCLUSIONS

NIPPV was successful in 42 (84%) patients, with improvements in ABG and pH for early recovery and reduced hospital stay.

A randomized controlled trial comparing non-invasive ventilation delivered using neurally adjusted ventilator assist (NAVA) or adaptive support ventilation (ASV) in patients with acute exacerbation of chronic obstructive pulmonary disease

PURPOSE

No study has compared neurally adjusted ventilator assist (NAVA) with adaptive support ventilation (ASV) during non-invasive ventilation (NIV) in subjects with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

MATERIALS AND METHODS

In this randomized controlled trial, we compared NAVA-NIV with ASV-NIV for delivering NIV in consecutive subjects with AECOPD. The primary outcome was NIV failure rate (invasive mechanical ventilation). The key secondary outcomes were number of NIV manipulations, asynchrony index, and 90-day mortality.

RESULTS

We enrolled 76 subjects (NAVA-NIV, n = 36, ASV-NIV, n = 40; 74% males) with a mean ± SD age of 61.4 ± 8.2 years. We found no difference in NIV failure rates between the two arms (NAVA-NIV vs. ASV-NIV; 8/36 [22.2%] vs. 8/40 [20%]; p = 0.83). The median physician manipulations for NIV were significantly less in the ASV-NIV arm than in the NAVA-NIV arm (2 [0.8-4] vs. 3 [2-5]; p= 0.014) during the initial 24-h. We found no difference in median asynchrony index (NAVA-NIV vs. ASV-NIV, 16.6% vs. 16.4%, p = 0.5) and 90-day mortality (22.2% vs. 17.5%, p = 0.67).

CONCLUSION

The use of NAVA-NIV was not superior to ASV-NIV in reducing NIV failure rates in AECOPD. Both NAVA-NIV and ASV-NIV had similar asynchrony index and 90-day mortality.

TRIAL REGISTRY

www.

CLINICALTRIALS

gov (NCT04414891).

Comparing Noninvasive Ventilation Delivered Using Neurally-Adjusted Ventilatory Assist or Pressure Support in Acute Respiratory Failure

BACKGROUND

The use of neurally-adjusted ventilatory assist (NAVA) during noninvasive ventilation (NIV) results in better patient-ventilator interaction. Whether this improves clinical outcomes lacks dedicated study.

METHODS

In this randomized controlled trial, we compared NAVA with PSV for delivering NIV in consecutive subjects with de novo acute respiratory failure. The primary outcomes were NIV failure rates and 28-d mortality. The secondary outcomes were asynchrony index, NIV-related complications, and others.

RESULTS

We enrolled 100 subjects (50 subjects each for NAVA and PSV, 60% male) with a mean ± SD age of 56.7 ± 12 y. There was no difference in NIV failure rates (30% vs 32%, P = .83) and 28-d mortality rates (18% vs 34%, P = .07) between the NAVA and PSV arms, respectively. The median asynchrony index was significantly lower with NAVA (6.7 vs 44.8, P < .001). The use of NAVA significantly reduced NIV-related complications (32% vs 58%, P = .01). In a post hoc analysis, the use of NAVA significantly reduced the 28-d mortality in subjects with COPD exacerbation.

CONCLUSIONS

The use of NAVA during NIV did not improve NIV failure rate or 28-d mortality in subjects with acute respiratory failure. However, patient-ventilator asynchrony and NIV-related complications were reduced with NAVA.

TRIAL REGISTRY

www.clinicaltrials.gov (NCT03271671).

ISCCM Guidelines for the Use of Non-invasive Ventilation in Acute Respiratory Failure in Adult ICUs

A. ACUTE HYPERCAPNIC RESPIRATORY FAILURE A1. Acute Exacerbation of COPD: Recommendations: NIV should be used in management of acute exacerbation of COPD in patients with acute or acute-on-chronic respiratory acidosis (pH = 7.25-7.35). (1A) NIV should be attempted in patients with acute exacerbation of COPD (pH <7.25 & PaCO2 ≥ 45) before initiating invasive mechanical ventilation (IMV) except in patients requiring immediate intubation. (2A). Lower the pH higher the chance of failure of NIV. (2B) NIV should not to be used routinely in normo- or mildly hyper-capneic patients with acute exacerbation of COPD, without acidosis (pH > 7.35). (2B) A2. NIV in ARF due to Chest wall deformities/Neuromuscular diseases: Recommendations: NIV may be used in patients of ARF due to chest wall deformity/Neuromuscular diseases. (PaCO2 ≥ 45) (UPP) A3. NIV in ARF due to Obesity hypoventilation syndrome (OHS): Recommendations: NIV may be used in AHRF in OHS patients when they present with acute hypercapnic or acute on chronic respiratory failure (pH 45). (3B) NIV/CPAP may be used in obese, hypercapnic patients with OHS and/or right heart failure in the absence of acidosis. (UPP) B.

NIV IN ACUTE HYPOXEMIC RESPIRATORY FAILURE

B1. NIV in Acute Cardiogenic Pulmonary Oedema: Recommendations: NIV is recommended in hospital patients with ARF, due to Cardiogenic pulmonary edema. (1A). NIV should be used in patients with acute heart failure/ cardiogenic pulmonary edema, right from emergency department itself. (1B) Both CPAP and BiPAP modes are safe and effective in patients with cardiogenic pulmonary edema. (1A). However, BPAP (NIV-PS) should be preferred in cardiogenic pulmonary edema with hypercapnia. (3A) B2. NIV in acute hypoxemic respiratory failure: Recommendations: NIV may be used over conventional oxygen therapy in mild early acute hypoxemic respiratory failure (P/F ratio <300 and >200 mmHg), under close supervision. (2B) We strongly recommend against a trial of NIV in patients with acute hypoxemic failure with P/F ratio <150. (2A) B3. NIV in ARF due to Chest Trauma: Recommendations: NIV may be used in traumatic flail chest along with adequate pain relief. (3B) B4. NIV in Immunocompromised Host: Recommendations: In Immunocompromised patients with early ARF, we may consider NIV over conventional oxygen. (2B). B5. NIV in Palliative Care: Recommendations: We strongly recommend use of NIV for reducing dyspnea in palliative care setting. (2A) B6. NIV in post-operative cases: Recommendations: NIV should be used in patients with post-operative acute respiratory failure. (2A) B6a. NIV in abdominal surgery: Recommendations: NIV may be used in patients with ARF following abdominal surgeries. (2A) B6b. NIV in bariatric surgery: Recommendations: NIV may be used in post-bariatric surgery patients with pre-existent OSA or OHS. (3A) B6c. NIV in Thoracic surgery: Recommendations: In cardiothoracic surgeries, use of NIV is recommended post operatively for acute respiratory failure to improve oxygenation and reduce chance of reintubation. (2A) NIV should not be used in patients undergoing esophageal surgery. (UPP) B6d. NIV in post lung transplant: Recommendations: NIV may be used for shortening weaning time and to avoid re-intubation following lung transplantation. (2B) B7. NIV during Procedures (ETI/Bronchoscopy/TEE/Endoscopy): Recommendations: NIV may be used for pre-oxygenation before intubation. (2B) NIV with appropriate interface may be used in patients of ARF during Bronchoscopy/Endoscopy to improve oxygenation. (3B) B8. NIV in Viral Pneumonitis ARDS: Recommendations: NIV cannot be considered as a treatment of choice for patients with acute respiratory failure with H1N1 pneumonia. However, it may be reasonable to use NIV in selected patients with single organ involvement, in a strictly controlled environment with close monitoring. (2B) B9. NIV and Acute exacerbation of Pulmonary Tuberculosis: Recommendations: Careful use of NIV in patients with acute Tuberculosis may be considered, with effective infection control precautions to prevent air-borne transmission. (3B) B10. NIV after planned extubation in high risk patients: Recommendation: We recommend that NIV may be used to wean high risk patients from invasive mechanical ventilation as it reduces re-intubation rate. (2B) B11. NIV for respiratory distress post extubation: Recommendations: We recommend that NIV therapy should not be used to manage respiratory distress post-extubation in high risk patients. (2B) C.

APPLICATION OF NIV

Recommendation: Choice of mode should be mainly decided by factors like disease etiology and severity, the breathing effort by the patient and the operator familiarity and experience. (UPP) We suggest using flow trigger over pressure triggering in assisted modes, as it provides better patient ventilator synchrony. Especially in COPD patients, flow triggering has been found to benefit auto PEEP. (3B) D.

MANAGEMENT OF PATIENT ON NIV

D1. Sedation: Recommendations: A non-pharmacological approach to calm the patient (Reassuring the patient, proper environment) should always be tried before administrating sedatives. (UPP) In patients on NIV, sedation may be used with extremely close monitoring and only in an ICU setting with lookout for signs of NIV failure. (UPP) E.

EQUIPMENT

Recommendations: We recommend that portable bilevel ventilators or specifically designed ICU ventilators with non-invasive mode should be used for delivering Non-invasive ventilation in critically ill patients. (UPP) Both critical care ventilators with leak compensation and bi-level ventilators have been equally effective in decreasing the WOB, RR, and PaCO2. (3B) Currently, Oronasal mask is the most preferred interface for non-invasive ventilation for acute respiratory failure. (3B) F.

WEANING

Recommendations: We recommend that weaning from NIV may be done by a standardized protocol driven approach of the unit. (2B) How to cite this article: Chawla R, Dixit SB, Zirpe KG, Chaudhry D, Khilnani GC, Mehta Y, et al. ISCCM Guidelines for the Use of Non-invasive Ventilation in Acute Respiratory Failure in Adult ICUs. Indian J Crit Care Med 2020;24(Suppl 1):S61-S81.

A Randomized Controlled Trial of Noninvasive Ventilation with Pressure Support Ventilation and Adaptive Support Ventilation in Acute Exacerbation of COPD: A Feasibility Study

Whether the use of adaptive support ventilation (ASV) during noninvasive ventilation (NIV) is as effective as pressure support ventilation (PSV) remains unknown. In this exploratory study, we compared the delivery of NIV with PSV vs. ASV. We randomized consecutive subjects with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) to receive NIV either with the PSV or the ASV mode. The primary outcome was NIV failure (endotracheal intubation, re-institution of NIV within 48 h of discontinuation or mortality). The secondary outcomes were the duration of mechanical ventilation (invasive and noninvasive), the number of NIV manipulations, the visual analogue score (VAS) for physician's ease of use and patient's comfort, and the complications of NIV use. We enrolled 74 subjects (n = 38, PSV; n = 36, ASV; 78.4% males) with a mean (SD) age of 60.5 (9.5) years. The baseline characteristics were similar between the two groups. The overall NIV failure rate was 28.4% and was similar between the two groups (PSV vs. ASV: 34.2% vs. 22.2%, p = 0.31). There was a 9% reduction in the intubation rate with ASV. There were six deaths (PSV vs. ASV: 2 vs 4, p =0.311). There was no difference in the secondary outcomes. The application of NIV using ASV was associated with a similar success rate as PSV in subjects with AECOPD. Due to the small sample size, the results of our study should be confirmed in a larger trial. Trial registry: ww.clinicaltrials.gov (NCT02877524).

Non-invasive ventilation in children and adults in low- and low-middle income countries: A systematic review and meta-analysis

PURPOSE

We systematically reviewed the effects of NIV for acute respiratory failure (ARF) in low- and low-middle income countries.

MATERIALS AND METHODS

We searched MEDLINE, CENTRAL, and EMBASE (to January 2016) for observational studies and trials of NIV for ARF or in the peri-extubation period in adults and post-neonatal children. We abstracted outcomes data and assessed quality. Meta-analyses used random-effect models.

RESULTS

Fifty-four studies (ten pediatric/n=1099; 44 adult/n=2904), mostly South Asian, were included. Common diagnoses were pneumonia and chronic obstructive pulmonary disease (COPD). Considering observational studies and the NIV arm of trials, NIV was associated with moderate risks of mortality (pooled risk 9.5%, 95% confidence interval (CI) 4.6-14.5% in children; 16.2% [11.2-21.2%] in adults); NIV failure (10.5% [4.6-16.5%] in children; 28.5% [22.4-34.6%] in adults); and intubation (5.3% [0.8-9.7%] in children; 28.8% [21.9-35.8%] in adults). The risk of mortality was greater (p=0.035) in adults with hypoxemic (25.7% [15.2-36.1%]) vs. hypercapneic (12.8% [7.0-18.6%]) ARF. NIV reduced mortality in COPD (relative risk [RR] 0.47 [0.27-0.79]) and in patients weaning from ventilation (RR 0.48 [0.28-0.80]). The pooled pneumothorax risk was 2.4% (0.8-3.9%) in children and 5.2% (1.0-9.4%) in adults. Meta-analyses had high heterogeneity.

CONCLUSIONS

NIV for ARF in these settings appears to be effective.

Noninvasive Ventilation for Acute Respiratory Failure due to Noncystic Fibrosis Bronchiectasis

Purpose of the Study:

Data regarding the use of noninvasive ventilation (NIV) for treatment of acute respiratory failure (ARF) among patients with noncystic fibrosis (CF) bronchiectasis are limited. We intend to describe our experience with NIV use in this setting.

Methodology:

This was a retrospective study which included 99 patients with bronchiectasis and ARF who required either NIV or invasive mechanical ventilation (IMV).

Results:

NIV was started as the primary modality of ventilatory support in 81 (66.3%) patients. Fifty-three (65.4%) patients were managed successfully with NIV. Twenty-eight (34.56%) patients failed NIV and required endotracheal intubation. Reasons for NIV failure were worsening or nonimprovement of ventilatory or oxygenation parameters (n = 15), hypotension (n = 6), worsening of sensorium (n = 3), and intolerance (n = 4). None of the patients failed NIV due to excessive respiratory secretions. The rate of correction of arterial blood gases was comparable between NIV and IMV groups. The total duration of stay (median [interquartile range] days) in hospital was comparable between patients treated with NIV and IMV (8 [7–10] vs. 11 [5–11]; P = 0.99), respectively. The mortality rate between NIV and IMV groups were statistically comparable (8.64% vs. 16.6%; P = 0.08). High APACHE score at admission was associated with NIV failure (odd's ratio [95% confidence interval]: 1.21 (1.07–1.38)].

Conclusions:

NIV is feasible for management of ARF with non-CF bronchiectasis. High APACHE may predict NIV failure among these patients.

Management of critical illness with non-invasive ventilation by an Australian HEMS

BACKGROUND

Non-invasive ventilation (NIV) therapy is widely used for the management of acute respiratory failure. The objective of this study was to investigate the current use of NIV during interhospital retrievals in an Australian physician-led aeromedical service.

METHODS

We reviewed patients receiving NIV during interhospital retrieval at the Greater Sydney Area Helicopter Medical Services (GSA-HEMS) over a 14-month period. The main objectives were to describe the number of retrievals using NIV, the need for intubation in NIV patients and the effect of the therapy on mission duration.

RESULTS

Over the study period, 3018 missions were reported; 106 cases (3.51%) involved administration of NIV therapy during the retrieval. The most common indication for NIV was pneumonia (34.0%). 86/106 patients received a successful trial of NIV therapy prior to interhospital transfer. 58 patients were transferred on NIV, while 28 patients had NIV removed during transport. None of these 86 patients required intubation or died, although 17/86 ultimately required intubation within 24 hours at the receiving centre. 20/106 patients required intubation at the referring hospital after a failed trial of NIV therapy. NIV was successfully used in all available transport platforms including rotary wing. Patients receiving NIV were found to have prolonged mission durations compared with other GSA-HEMS patients (222.5 vs 193 min). This increase in mission duration was largely attributable to NIV failure, resulting in a need for Rapid Sequence Intubation at the referring hospital.

CONCLUSIONS

With careful patient selection, the use of interhospital NIV is feasible and appears to be safe in a retrieval system with care provided by a critical care physician.

Cost-effectiveness of noninvasive ventilation for chronic obstructive pulmonary disease-related respiratory failure in Indian hospitals without ICU facilities

Introduction:

The majority of Indian hospitals do not provide intensive care unit (ICU) care or ward-based noninvasive positive pressure ventilation (NIV). Because no mechanical ventilation or NIV is available in these hospitals, the majority of patients suffering from respiratory failure die.

Objective:

To perform a cost-effective analysis of two strategies (ward-based NIV with concurrent standard treatment vs standard treatment alone) in chronic obstructive pulmonary disease (COPD) respiratory failure patients treated in Indian hospitals without ICU care.

Materials and Methods:

A decision-analytical model was created to compare the cost-effectiveness for the two strategies. Estimates from the literature were used for parameters in the model. Future costs were discounted at 3%. All costs were reported in USD (2012). One-way, two-way, and probabilistic sensitivity analysis were performed. The time horizon was lifetime and perspective was societal.

Results:

The NIV strategy resulted in 17.7% more survival and was slightly more costly (increased cost of $101 (USD 2012) but resulted in increased quality-adjusted life-years (QALYs) (1.67 QALY). The cost-effectiveness (2012 USD)/QALY in the standard and NIV groups was $78/QALY ($535.02/6.82) and $75/QALY ($636.33/8.49), respectively. Incremental cost-effectiveness ratio (ICER) was only $61 USD/QALY. This was substantially lower than the gross domestic product (GDP) per capita for India (1489 USD), suggesting the NIV strategy was very cost effective. Using a 5% discount rate resulted in only minimally different results. Probabilistic analysis suggests that NIV strategy was preferred 100% of the time when willingness to pay was >$250 2012 USD.

Conclusion:

Ward-based NIV treatment is cost-effective in India, and may increase survival of patients with COPD respiratory failure when ICU is not available.

A study on the role of noninvasive ventilation in mild-to-moderate acute respiratory distress syndrome

Aim:

There is sparse data on the role of noninvasive ventilation (NIV) in acute respiratory distress syndrome (ARDS) from India. Herein, we report our experience with the use of NIV in mild to moderate ARDS.

Materials and Methods:

This was a prospective observational study involving consecutive subjects of ARDS treated with NIV using an oronasal mask. Patients were monitored clinically with serial arterial blood gas analysis. The success of NIV, duration of NIV use, Intensive Care Unit stay, hospital mortality, and improvement in clinical and blood gas parameters were assessed. The success of NIV was defined as prevention of endotracheal intubation.

Results:

A total of 41 subjects (27 women, mean age: 30.9 years) were included in the study. Tropical infections followed by abdominal sepsis were the most common causes of ARDS. The use of NIV was successful in 18 (44%) subjects, while 23 subjects required intubation. The median time to intubation was 3 h. Overall, 19 (46.3%) deaths were encountered, all in those requiring invasive ventilation. The mean duration of ventilation was significantly higher in the intubated patients (7.1 vs. 2.6 days, P = 0.004). Univariate analysis revealed a lack of improvement in PaO₂/FiO₂ at 1 h and high baseline Acute Physiology and Chronic Health Evaluation II (APACHE II) as predictors of NIV failure.

Conclusions:

Use of NIV in mild to moderate ARDS helped in avoiding intubation in about 44% of the subjects. A baseline APACHE II score of >17 and a PaO₂/FiO₂ ratio <150 at 1 h predicts NIV failure.

Evaluation of efficacy of non-invasive ventilation in Non-COPD and non-trauma patients with acute hypoxemic respiratory failure: A systematic review and meta-analysis

Non-invasive ventilation (NIV) has been widely supported in the past two decades as an effective application in avoiding the need for endotracheal intubation (ETI) and reducing associated mortality in acute hypoxemic respiratory failure (AHRF) patients. However, the efficacy of NIV in AHRF patients, non-related to chronic obstructive pulmonary disease (COPD) and trauma is still controversial in the field of medical research. This retrospective study aimed to evaluate the efficacy of NIV as an adjunctive therapy in non-COPD and non-traumatic AHRF patients. Data of 11 randomized control trials (RCTs), which were conducted between 1990 and 2010 to determine the efficacy of NIV in non-COPD and non-traumatic AHRF patients, were reviewed from the PUBMED, MEDLINE, Cochrane Library, and EMBASE databases. Parameters monitored in this study included the ETI rate, fatal complications, mortality rate of patients, and their ICU and hospital duration of stay. Overall results showed a statistically significant decrease in the rate of ETI, mortality, and fatal complications along with reduced ICU and hospital length of stay in non-COPD and non-trauma AHRF patients of various etiologies. This systematic review suggests that non-COPD and non-trauma AHRF patients can potentially benefit from NIV as compared with conventional treatment methods. Observations from various cohort studies, observational studies, and previously published literature advocate on the efficacy of NIV for treating non-COPD and non-traumatic AHRF patients. However, considering the diversity of studied populations, further studies and more specific trials on less heterogeneous AHRF patient groups are needed to focus on this aspect.

Noninvasive ventilation: Are we overdoing it?

BACKGROUND

Use of noninvasive ventilation (NIV) outside guideline recommendations is common. We audited use of NIV in our tertiary care critical care unit (CCU) to evaluate appropriateness of use and patient outcomes when used outside level I recommendations.

MATERIALS AND METHODS

Prospective observational study of all patients requiring NIV. Clinical parameters and arterial blood gases were recorded at initiation of NIV and 2 h later (or earlier if clinically warranted). NIV titration and decision to intubate were left to the discretion of treating intensivist. Patients were categorized into two groups: Group 1: Those with level I indications for use of NIV and group 2: All other levels of indications. Patients were followed until hospital discharge.

RESULTS

From January 2010 to June 2010, 1120 patients were admitted to the CCU. Of these 106 patients required NIV support with 40.6% (n = 43/106) being in group 1 and 59.4% (n = 63/106) in group 2. Of these 35.8% patients (38/106) failed NIV and required endotracheal intubation. NIV failure rates (41.27% vs. 27.91%; P = 0.02) and mortality (30.6% vs. 18.6%; P = 0.03) were significantly higher in group 2 patients. In a logistic regression analysis Acute Physiology and Chronic Health Evaluation (APACHE) II score (P = 0.02), time on NIV before intubation (P = 0.001) and baseline PaCO2 levels (P = 0.01) were strongly associated with mortality.

CONCLUSION

Noninvasive ventilation failure and mortality rates were significantly higher when used outside level I recommendations. APACHE II score, baseline PaCO2 and duration on NIV prior to intubation were predictors of increased mortality.

Guidelines for diagnosis and management of chronic obstructive pulmonary disease: Joint ICS/NCCP (I) recommendations

Chronic obstructive pulmonary disease (COPD) is a major public health problem in India. Although several International guidelines for diagnosis and management of COPD are available, yet there are lot of gaps in recognition and management of COPD in India due to vast differences in availability and affordability of healthcare facilities across the country. The Indian Chest Society (ICS) and the National College of Chest Physicians (NCCP) of India have joined hands to come out with these evidence-based guidelines to help the physicians at all levels of healthcare to diagnose and manage COPD in a scientific manner. Besides the International literature, the Indian studies were specifically analyzed to arrive at simple and practical recommendations. The evidence is presented under these five headings: (a) definitions, epidemiology, and disease burden; (b) disease assessment and diagnosis; (c) pharmacologic management of stable COPD; (d) management of acute exacerbations; and (e) nonpharmacologic and preventive measures. The modified grade system was used for classifying the quality of evidence as 1, 2, 3, or usual practice point (UPP). The strength of recommendation was graded as A or B depending upon the level of evidence.

Incidence, prevalence, risk factor and outcome of delirium in intensive care unit: a study from India

OBJECTIVE

To evaluate the incidence, prevalence, risk factors and outcome of delirium in the respiratory intensive care unit of a tertiary care hospital.

METHODS

Consecutive patients admitted to an eight-bed respiratory intensive care unit were screened for presence of delirium by a psychiatrist. Patients found to have delirium were evaluated using univariate techniques for their clinical profiles, risk factors for delirium, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, duration of stay (in days) and outcome at discharge from intensive care unit besides evaluation on Delirium Rating Scale-Revised 98 version (DRS-R-98).

RESULTS

Incidence and prevalence rate of delirium were 24.4% and 53.6% respectively. Univariate analyses revealed that the prevalence of delirium was higher (64%) in mechanically ventilated patients. The predisposing risk factors identified for delirium in univariate analysis were higher age; higher Glasgow Coma Scale score; increased APACHE II score; hyperuricemia; hypoalbuminemia; presence of acidosis; abnormal alkaline transferase levels; use of mechanical ventilation; higher number of total medication received and use of sedative, steroids and insulin. Univariate analysis showed that patients who were diagnosed with delirium had significantly longer duration of intensive care unit (ICU) stay and higher mortality rates. Age, multiple organ failure, hypoactive delirium and higher DRS-R-98 scores were significant risk factors for mortality in patients with delirium.

CONCLUSIONS

Delirium is highly prevalent in the ICU setting and delirium is associated with longer ICU stay and higher mortality.

Non-invasive ventilation for acute exacerbation of COPD with very high PaCO(2): A randomized controlled trial

Objective:

To assess the role of non-invasive positive pressure ventilation (NIPPV) for management of Indian patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Materials and Methods:

Forty patients (mean age 57.6 ± 10.8 years; M:F 31:9) with AECOPD with pH <7.35, admitted to the intensive care unit were included. Patients were randomized to receive NIPPV (N, n = 20) with conventional therapy or conventional therapy (C, n = 20) alone at admission. NIPPV was given through the nasal mask. Incidence of need of endotracheal intubation (ETI) was the primary efficacy variable. Hospital mortality, duration of hospital stay and change in clinical and blood gas parameters were the secondary outcome variables.

Results:

Mean pH at baseline for N and C groups were similar (7.23 ± 0.07) whereas PaCO₂ was 85.4 ± 14.8 and 81.1 ± 11.6 mm of Hg, respectively. At one hour, patients in N group had greater improvement in pH (P = 0.017) as well as PaCO₂ (P = 0.04) which corroborated with clinical improvement. Whereas need of ETI was reduced in patients who received NIPPV (3/20 vs 12/20, P = 0.003), in-hospital mortality was similar (3/20 and 2/20, P = NS). The mean duration of hospital stay was significantly shorter in N group (9.4 ± 4.3 days) as compared to C group (17.8 ± 2.6 days); P = 0.001.

Conclusions:

In patients with AECOPD, NIPPV leads to rapid improvement in blood gas parameters and reduces the need for ETI

COPD exacerbation: mortality prognosis factors in a respiratory care unit

OBJECTIVE

The aim of our study was to investigate the mortality predictive factors after a severe exacerbations of COPD admitted to a Spanish respiratory intermediate care unit (IRCU).

PATIENTS AND METHODS

Prospective observational 2 years study, where we included all episodes of acute exacerbations of COPD with hypercapnic respiratory failure admitted in an IRCU. We analyzed different sociodemographic, functional and clinical variables including physical activity.

RESULTS

We collected data from 102 consecutive episodes admitted to IRCU (90.1% men). Mean age was 69.4±10.6. The mean APACHE II was 19.6±5.0 and 9.5% presented a failure of other non respiratory organ. Non invasive ventilation was applied in 75.3% of the episodes and this treatment failed in 11.6% of them. The duration of stay in the IRCU was 3.5±2.1 days and 8.0±5.3 days in the hospital. The hospital mortality rate was 6.9%, and another 12.7% after 90 days of discharged. In order to predict hospital mortality, multivariant statistics identified a model with AUC of 0.867, based in 3 variables: the number of previous year admission for COPD exacerbation (p=0,048), the respiratory rate after 2 hours of treatment in the IRCU (p=0.0484) and the severity of the disease established with ADO score (p=0.0241).

CONCLUSIONS

The number of previous year admission for COPD exacerbation, the severity of the disease established with ADO score, the respiratory rate after 2 hours of treatment, allow us to identify what patients with a COPD exacerbation admitted in a IRCU can die during this episode.

Oxygen saturation/fraction of inspired oxygen ratio is a simple predictor of noninvasive positive pressure ventilation failure in critically ill patients

PURPOSE

Noninvasive positive pressure ventilation (NPPV) can improve outcomes of critically ill patients. Early and simple predictors of NPPV outcome could improve clinical management of patients with respiratory failure.

MATERIALS AND METHODS

A prospective observational study was conducted in a medical intensive care unit of a tertiary medical center. Patients requiring NPPV were included and followed. Clinical data including respiratory mechanics at the time of NPPV initiation, and clinical outcomes were recorded. Data were analyzed to identify variables that distinguished NPPV success or failure.

RESULTS

A total of 133 patients were included in the study. Noninvasive positive pressure ventilation success rate was 41%. Patients diagnosed with malignancy had only 29% NPPV success rate. Among patients without malignancy, higher oxygen saturation, oxygen saturation/fraction of inspired oxygen (SF) ratios, and SF/minute ventilation ratios were associated with NPPV success. Receiver operating characteristic curve analyses identify SF ratio less than 98.5 to be a specific (89% specificity, P = .013) predictor of NPPV failure. Furthermore, for patients requiring at least 24 hours of NPPV support, tidal volume/predicted body weight ratio negatively correlated with respiratory improvement.

CONCLUSIONS

For patients without malignancy, SF ratios at the time of NPPV initiation discriminated NPPV success and failure, and could be used to help guide the management of critically ill patients who require ventilatory support.