Effect of intrapulmonary percussive ventilation on expiratory flow limitation in chronic obstructive pulmonary disease patients

Purpose

The aims of this prospective study were (1) to select, after weaning and extubation, chronic obstructive pulmonary disease (COPD) patients with expiratory flow limitation (EFL) measured by the negative expiratory pressure method and (2) to assess, in these patients, the short-term (30 minutes) physiologic effect of a session of intrapulmonary percussive ventilation (IPV).

Materials and Methods

All COPD patients who were intubated and needed weaning from mechanical ventilation were screened after extubation. The patients were placed in half-sitting position and breathed spontaneously. The EFL and the airway occlusion pressure after 0.1 second (P0.1) were measured at the first hour after extubation. In COPD patients with EFL, an IPV session of 30 minutes was promptly performed by a physiotherapist accustomed to the technique. Expiratory flow limitation, gas exchange, and P0.1 were recorded at the end of the IPV session.

Results

Among 35 patients studied after extubation, 25 patients presented an EFL and were included in the study. Intrapulmonary percussive ventilation led to a significant improvement in EFL, respectively, before and 30 minutes after IPV (65.4 ± 18.2 vs 35.6 ± 22.8; P < .05). Three patients were not expiratory flow limited after IPV. Intrapulmonary percussive ventilation led to a significant decrease in P0.1 (3.9 ± 1.6 vs 2.8 ± 1.1; P < .05). Thirty minutes of IPV led to a significant increase in Pao₂ and pH and a decrease in Paco₂ and respiratory rate (P < .05).

Conclusion

In COPD patients, a session of IPV allowed a significant reduction of EFL and of P01 and a significant improvement of gas exchange.     

Predictors of failure of noninvasive ventilation in patients with severe community-acquired pneumonia

Purpose

The study aimed to investigate cardiorespiratory parameters potentially predictive of failure of noninvasive ventilation (NIV) in severe community-acquired pneumonia (CAP).

Patients and Methods

Sixty-four consecutive patients with severe CAP entered the study and underwent NIV with a helmet. Arterial blood gases, Pao₂/FIo₂, and oxygenation index (OI; mean airway pressure × FIo₂ × 100/Pao₂) were determined before and after a 1-hour trial of NIV.

Results

Noninvasive ventilation succeeded in 28 patients (43%) and failed in 36 patients (56%). Patients who avoided intubation had significantly (P < .05) shorter stays in ICU and lower rates of mortality in ICU and in hospital. Patients who failed NIV had higher Simplified Acute Physiology Score II at ICU admission (33 ± 11 versus 29 ± 9) and lower pH before NIV trial (7.37 versus 7.44). Furthermore, patients who required intubation failed to improve or worsened arterial blood gases during NIV trial and, by the end of the trial, had lower (P < .05) pH (7.34 versus 7.44) and Pao₂/FiO₂ (177 versus 228) and higher OI (8.6 versus 5.0) and respiratory rate (28 versus 23 breaths/min). In a multivariate analysis, post-NIV to pre-NIV deltas of Pao₂/FiO₂ and of OI were independent predictors of NIV failure, with OI delta being significantly more accurate.

Conclusions

Noninvasive ventilation failed in approximately half patients with severe CAP. Posttrial to pretrial deltas of Pao₂/FiO₂ and OI may help to guide decision about endotracheal intubation.     

Ventilator settings and monitoring parameter targets for initiation of continuous mandatory ventilation: A questionnaire study

Purpose

To inform development of educational tools, we sought to identify initial ventilator settings and monitoring targets for 3 scenarios.

Method

A survey was e-mailed to Canadian Society of Respiratory Therapists members with 2 reminders in March/April 2011.

Results

Total evaluable surveys were 363. More participants selected pressure as opposed to volume ventilation for acute respiratory distress syndrome (ARDS; 77%) than for chronic obstructive pulmonary disease (COPD; 50%) and postoperative ventilation (32%; P < .001). Mean tidal volume was lower for ARDS than for COPD and postoperative ventilation (5.7, 6.9, and 7.2 mL/kg, respectively; P < .001). Maximum acceptable plateau pressures were highest for ARDS (30 cm H₂O vs 29 cm H₂O [COPD] and 27 cm H₂O [postoperative], P < .001). Initial positive expiratory end pressure (12 cm H₂O vs 7 cm H₂O vs 5 cm H₂O) and fraction of inspired oxygen (Fio₂; 1.0 vs 0.5 vs 0.3) were also higher for ARDS (both P < .001); however, only 8% selected a positive expiratory end pressure/Fio₂ combination as recommended by ARDSnet. Values of oxygen saturation as measured by pulse oximetry of 97% (ARDS) and 94% (COPD and postoperative) were considered appropriate for Fio₂ reduction. The lowest pH was 7.28 vs 7.23 vs 7.26; the highest pH was 7.46 vs 7.44 vs 7.46 (P < .001). Partial pressure of carbon dioxide (arterial) of 51 mm Hg (postoperative) to 65 mm Hg (ARDS) was considered acceptable.

Conclusion

Lung protective ventilation was favored, yet distinct differences in ventilator settings were evident. Monitoring targets suggested relatively conservative practices for Fio₂ reduction but an understanding of permissive hypercapnia.     

Noninvasive ventilation in the event of acute respiratory failure in patients with idiopathic pulmonary fibrosis

Background

Some patients with idiopathic pulmonary fibrosis (IPF) develop severe acute respiratory failure (ARF) requiring admission to an intensive care unit (ICU) and ventilatory support. A limited number of observational studies have reported that noninvasive ventilation (NIV) can be an effective treatment to support breathing and to prevent use of invasive mechanical ventilation in these patients. This study aimed to retrospectively investigate the clinical status and outcomes in IPF patients receiving NIV for ARF and to identify those clinical and laboratory characteristics, which could be considered risk factors for its failure.

Methods

This is a retrospective analysis of short-term outcomes in 18 IPF patients being administered NIV for ARF. This study was conducted in a 4-bed respiratory ICU (RICU) in a university hospital. Eighteen IPF patients who were administered NIV between January 1, 2005, and April 30, 2013, were included. The outcome measures are the need for endotracheal intubation despite NIV treatment and mortality rate during their RICU stay. The length of the patients' stay in the RICU and their survival rate following RICU admission were also evaluated.

Results

Noninvasive ventilation was successful in 8 patients and unsuccessful in 10 who required endotracheal intubation. All the patients in the NIV failure group died within 20.2 ± 15.3 days of intubation. The patients in the NIV success group spent fewer days in the RICU (11.6 ± 4.5 vs 24.6 ± 13.7; P = .0146). The median survival time was significantly shorter for the patients in the NIV failure with respect to the success group (18.0 [95% confidence interval {CI}, 9.0-25.0] vs 90.0 [95% CI, 65.0-305.0] days; P < .0001); the survival rate at 90 days was, likewise, lower in the NIV failure group (0% vs 34% ± 19.5%). At admission, the patients in the failure group had significantly higher respiratory rate values (36.9 ± 7.8 vs 30.5 ± 3.3 breaths/min; P = .036), plasma N-terminal fragment of the prohormone of B-type natriuretic peptide (NT-proBNP) levels (4528.8 ± 4012.8 vs 634.6 ± 808.0 pg/mL; P = .023) and serum C-reactive protein values (72.0 ± 50.0 vs 20.7 ± 24.0 μg/mL; P = .0289) with respect to those in the success group. Noninvasive ventilation failure was correlated to the plasma NT-proBNP levels at RICU admission (P = .0326) with an odds ratio of 12.2 (95% CI, 1.2 to infinity) in the patients with abnormally high values (>900 pg/mL).

Conclusions

The outcome of IPF patients who were administered NIV was quite poor. The use of NIV was, nevertheless, found to be associated with clinical benefits in selected IPF patients, preventing the need for intubation and reducing the rate of complications/death. Elevated plasma NT-proBNP levels at the time of ICU admission is a simple clinical marker for poor NIV outcome.     

Extended prone position ventilation in severe acute respiratory distress syndrome: A pilot feasibility study

Objectives

The aim of the study was to evaluate the safety of extended prone position ventilation (PPV) and its impact on respiratory function in patients with severe acute respiratory distress syndrome (ARDS).

Design

This was a prospective interventional study.

Setting

Patients were recruited from a mixed medical-surgical intensive care unit in a university hospital.

Patients

Fifteen consecutive patients with severe ARDS, previously unresponsive to positive end-expiratory pressure adjustment, were treated with PPV.

Intervention

Prone position ventilation for 48 hours or until the oxygenation index was 10 or less (extended PPV).

Results

The elapsed time from the initiation of mechanical ventilation to pronation was 35 ± 11 hours. Prone position ventilation was continuously maintained for 55 ± 7 hours. Two patients developed grade II pressure ulcers of small extent. None of the patients experienced life-threatening complications or hemodynamic instability during the procedure. The patients showed a statistically significant improvement in Pao₂/Fio₂ (92 ± 12 vs 227 ± 43, P < .0001) and oxygenation index (22 ± 5 vs 8 ± 2, P < .0001), reduction of PaCo₂ (54 ± 9 vs 39 ± 4, P < .0001) and plateau pressure (32 ± 2 vs 27 ± 3, P < .0001), and increment of the static compliance (21 ± 3 vs 37 ± 6, P < .0001) with extended PPV. All the parameters continued to improve significantly while they remained in prone position and did not change upon returning the patients to the supine position.

Conclusions

The results obtained suggest that extended PPV is safe and effective in patients with severe ARDS when it is carried out by a trained staff and within an established protocol. Extended PPV is emerging as an effective therapy in the rescue of patients from severe ARDS.     

Comparison of invasive and noninvasive positive pressure ventilation delivered by means of a helmet for weaning of patients from mechanical ventilation

Purpose

The effectiveness of noninvasive positive pressure ventilation delivered by helmet (H-NPPV) as a weaning approach in patients with acute respiratory failure is unclear.

Patients and methods

We randomly and evenly assigned 64 patients intubated for acute respiratory failure to conventional weaning with invasive mechanical ventilation (IMV) or H-NPPV. The primary end point was a reduction in IMV duration by 6 days between the 2 groups. Secondary end points were the occurrence of ventilator-associated pneumonia and major complications, duration of mechanical ventilation and weaning, intensive care unit and hospital length of stay, and survival.

Results

The mean duration of IMV was significantly reduced in the H-NPPV group compared with the IMV group (P < .0001), without significant difference in duration of weaning (P = .26) and total ventilatory support (P = .45). In the H-NPPV group, the incidence of major complications was less than the IMV group (P = .032). Compared with the H-NPPV group, the IMV group was associated with a greater incidence of VAP (P = .018) and an increased risk of nosocomial pneumonia (P = .049). The mortality rate was similar between the groups, with no significant difference in overall intensive care unit (P = .47) or hospital length of stay (P = .37).

Conclusions

H-NPPV was well tolerated and effective in patients who were difficult to wean.     

A controlled trial of noninvasive ventilation for chronic obstructive pulmonary disease exacerbations

Purpose

This prospective, multicenter, double-blind, placebo-controlled study tested the hypothesis that noninvasive positive pressure ventilation reduces the need for endotracheal intubation in patients hospitalized in a pulmonary ward because of acute exacerbation of chronic obstructive pulmonary disease.

Materials and Methods

Seventy-five consecutive patients with exacerbation (pH, 7.31 ± 0.02; Pao₂, 45 ± 9 mm Hg; Paco₂, 69 ± 13 mm Hg) were randomly assigned to receive noninvasive ventilation or sham noninvasive ventilation during the first 3 days of hospitalization on top of standard medical treatment.

Results

The need for intubation (according to predefined criteria) was lower in the noninvasive ventilation group (13.5% vs 34%, P < .01); in 31 patients with pH not exceeding 7.30, these percentages were 22% and 77%, respectively (P < .001). Arterial pH and Paco₂ improved in both groups, but changes were enhanced by noninvasive ventilation. Length of stay was lower in the noninvasive ventilation group (10 ± 5 vs 12 ± 6 days, P = .06). In-hospital mortality was similar in both groups.

Conclusions

These results demonstrate that noninvasive positive pressure ventilation, in a pulmonary ward, reduces the need for endotracheal intubation, particularly in the more severe patients, and leads to a faster recovery in patients with acute exacerbation of chronic obstructive pulmonary disease.     

Randomized Trial of Bilevel versus Continuous Positive Airway Pressure for Acute Pulmonary Edema

Background

Studies have shown different clinical outcomes of noninvasive positive pressure ventilation (NPPV) from those of continuous positive airway pressure (CPAP).

Objective

We evaluated whether bilevel positive airway pressure (BPAP) more rapidly improves dyspnea, ventilation, and acidemia without increasing the myocardial infarction (MI) rate compared to continuous positive pressure ventilation (CPAP) in patients with acute cardiogenic pulmonary edema (APE).

Methods

Patients with APE were randomized to either BPAP or CPAP. Vital signs and dyspnea scores were recorded at baseline, 30 min, 1 h, and 3 h. Blood gases were obtained at baseline, 30 min, and 1 h. Patients were monitored for MI, endotracheal intubation (ETI), lengths of stay (LOS), and hospital mortality.

Results

Fourteen patients received CPAP and 13 received BPAP. The two groups were similar at baseline (ejection fraction, dyspnea, vital signs, acidemia/oxygenation) and received similar medical treatment. At 30 min, PaO₂:FIO₂ was improved in the BPAP group compared to baseline (283 vs. 132, p < 0.05) and the CPAP group (283 vs. 189, p < 0.05). Thirty-minute dyspnea scores were lower in the BPAP group compared to the CPAP group (p = 0.05). Fewer BPAP patients required intensive care unit (ICU) admission (38% vs. 92%, p < 0.05). There were no differences between groups in MI or ETI rate, LOS, or mortality.

Conclusions

Compared to CPAP to treat APE, BPAP more rapidly improves oxygenation and dyspnea scores, and reduces the need for ICU admission. Further, BPAP does not increase MI rate compared to CPAP.     

Diagnostic yield of coronary angiography in patients with acute chest pain: role of noninvasive test

Objectives

This study investigated the diagnostic yield of invasive coronary angiography (CAG) and the impact of noninvasive test (NIV) in patients presented to emergency department (ED) with acute chest pain.

Methods

Patients 50 years or older who visited ED with acute chest pain and underwent CAG were identified retrospectively. Those with ischemic electrocardiogram, elevated cardiac enzyme, known coronary artery disease (CAD), history of cardiac surgery, renal failure, or allergy to radiocontrast were excluded. Diagnostic yields of CAG to detect significant CAD or differentiate the need for revascularization were analyzed according to whether NIV was performed and its result.

Results

Among the total 375 consecutive patients, significant CAD was observed in 244 (65.1%). Diagnostic yields of CAG were higher in patients who underwent NIV before CAG, but the discriminative effect was modest (59.7% vs 70.7% [P = .026] for detection of CAD; 45.0% vs 50.5% [P = .285] for revascularization). Positive results of NIV were significantly associated with the presence of CAD and the need for revascularization, when compared with patients without NIV or patients with negative results (P < .001, respectively).

Conclusion

The diagnostic yield of CAG was only 65% in low- to intermediate-risk ED patients with acute chest pain. Performing of NIV provided only modest improvement in diagnostic yield of CAG. The unexpectedly low diagnostic yield might be attributable to the underuse of NIV and misinterpretation of physicians. We suggest the use of NIV as a gatekeeper to discriminate patients who require CAG and/or revascularization, and for this, better risk stratification and appropriate application of NIV are required.     

Racial differences in withdrawal of mechanical ventilation do not alter mortality in neurologically injured patients

Purpose

Racial differences in withdrawal of mechanical ventilation (WMV) have been demonstrated among patients with severe neurologic injuries. We ascertained whether such differences might be accounted for by imbalances in socioeconomic status or disease severity, and whether such racial differences impact hospital mortality or result in greater discharge to long-term care facilities.

Materials and methods

We evaluated WMV among 1885 mechanically ventilated patients with severe neurologic injury (defined as Glasgow Coma Scale < 9), excluding those progressing to brain death within the first 48 hours.

Results

Withdrawal of mechanical ventilation was less likely in nonwhite patients (22% vs 31%, P < .001). Nonwhites were younger and were more likely to have Medicaid or no insurance, live in ZIP codes with low median household incomes, be unmarried, and have greater illness severity; but after adjustment for these variables, racial difference in WMV persisted (odds ratio, 0.56; 95% confidence interval, 0.42-0.76). Nonwhite patients were more likely to die instead with full support or progress to brain death, resulting in equivalent overall hospital mortality (40% vs 42%, P = .44). Among survivors, nonwhites were more likely to be discharged to long-term care facilities (27% vs 17%, P < .001).

Conclusions

Surrogates of nonwhite neurologically injured patients chose WMV less often even after correcting for socioeconomic status and other confounders. This difference in end-of-life decision making does not appear to alter hospital mortality but may result in more survivors left in a disabled state.     

Mechanical ventilation in the emergency department for 24 hours or longer is associated with delayed weaning

Purpose

We examined various aspects of critical care to identify factors in the emergency department (ED) that affected the overall duration of mechanical ventilation (MV). We specifically focused on whether 24 hours of ED MV affected the weaning success and the duration of MV.

Materials and Methods

Mechanical ventilation cases that started in the ED because of purely respiratory problems were enrolled in the retrospective cohort. We recorded demographic data, duration of MV in ED, various severity scores, previously known factors of prolonged MV, and achievement of ventilator weaning. All the significant factors in univariate survival analyses were included in a multivariate analysis.

Results

The estimated median of the entire duration of MV was longer in patients who received 24 hours or more of MV in ED compared with that of patients who received MV for less than 24 hours (33.0 vs 15.4 days, P = .003). Mechanical ventilation for longer than 24 hours in the ED remained a significant factor that prolonged the entire MV duration in the multivariate analysis (hazard ratio, 0.577; P = .019). Hypoalbuminemia and abbreviated mortality in ED sepsis (MEDS) score were also independently correlated (P ≤ .001 for both).

Conclusions

Mechanical ventilation in the ED for 24 hours or longer is associated with delayed ventilator weaning.     

Effects of inhalational bronchodilator treatment during noninvasive ventilation in severe chronic obstructive pulmonary disease exacerbations

Purpose

To study the effects of withdrawing noninvasive ventilation (NIV) used during acute exacerbation of chronic obstructive pulmonary disease for the delivery of aerosolized medications on physiologic parameters and dyspnea sensation.

Methods

We measured accessory muscle use, dyspnea sensation, heart rate (HR), respiratory rate (RR), blood pressure (BP), and arterial blood gases during NIV, 10 minutes after cessation of NIV (with oxygen), after nebulization with salbutamol (5 mg) and ipratropium (500 μg), and again, on restitution of NIV.

Results

We studied 19 patients (3 women; mean [±SD] age, 72 [± 9] years) with a mean postbronchodilator forced expiratory volume in 1 second 40% (±12) of predicted. Baseline RR (23/min), HR (98/min), BP (121/62 mm Hg), Spo₂ (95%), pH (7.31 [±0.06]), Paco₂ (65 [±12] mm Hg), and Borg score (1.8 [±0.43]) were recorded. There were no significant changes in physiologic parameters and oxygenation between NIV and nebulization periods. The only physiologic changes observed were increase in systolic BP (SBP, P = .012) and HR (P = .003) after nebulization. However, significant decrease in oxygen saturation (P = .009) and increase in SBP (P = nonsignificant) were observed between NIV and oxygenation phases.

Conclusion

Short-term cessation of NIV for nebulization treatment did not result in distress, discomfort, or physiologic instabilities. The only detectable changes were increase in SBP and HR, probably due to the systemic adrenergic effects of salbutamol.     

Observational study of patient-ventilator asynchrony and relationship to sedation level

Purpose

Clinicians frequently administer sedation to facilitate mechanical ventilation. The purpose of this study was to examine the relationship between sedation level and patient-ventilator asynchrony.

Materials and Methods

Airway pressure and airflow were recorded for 15 minutes. Patient-ventilator asynchrony was assessed by determining the number of breaths demonstrating ineffective triggering, double triggering, short cycling, and prolonged cycling. Ineffective triggering index (ITI) was calculated by dividing the number of ineffectively triggered breaths by the total number of breaths (triggered and ineffectively triggered). Sedation level was assessed by the following 3 methods: Richmond Agitation-Sedation Scale (RASS), awake (yes or no), and delirium (Confusion Assessment Method for the intensive care unit [CAM-ICU]).

Results

Twenty medical ICU patients underwent 35 observations. Ineffective triggering was seen in 17 of 20 patients and was the most frequent asynchrony (88% of all asynchronous breaths), being observed in 9% ± 12% of breaths. Deeper levels of sedation were associated with increasing ITI (awake, yes 2% vs no 11%; P < .05; CAM-ICU, coma [15%] vs delirium [5%] vs no delirium [2%]; P < .05; RASS, 0, 0% vs −5, 15%; P < .05). Diagnosis of chronic obstructive pulmonary disease, sedative type or dose, mechanical ventilation mode, and trigger method had no effect on ITI.

Conclusions

Asynchrony is common, and deeper sedation level is a predictor of ineffective triggering.     

Non-invasive mechanical ventilation in Australian emergency departments: A prospective observational cohort study

Objectives

Data describing use of non-invasive ventilation (NIV) in the emergency department (ED) setting consist primarily of physician surveys. Our objective was to conduct a prospective study to document the characteristics of patients receiving NIV, interfaces, mode, and parameters used as well as NIV duration and decision-making responsibility.

Methods

We conducted a 2-month prospective observational study of adult patients who received NIV in 24 EDs. Patient characteristics, delivery methods, and decision-making responsibility were documented for each ED presentation.

Results

Data were recorded on 245 patients; 185 patients received non-invasive positive pressure ventilation (NIPPV) and 60 received continuous positive airway pressure (CPAP). Acute cardiogenic pulmonary oedema (ACPO) (80/245, 33%) and exacerbation of chronic obstructive pulmonary disease (COPD) (75/245, 31%) were the two most frequent indications for NIV. Compared to patients with respiratory failure from other aetiologies, those with ACPO were more likely to receive CPAP (28/80 [35%] versus 32/165 [19%] P = 0.008). Initial NIV settings were selected by ED nurses for 118/245 (48%) patients, by ED physicians for 118/245 (48%) patients, and by ICU staff for 3/245 (1.5%) patients (not reported for 6 [2.5%] patients). The role of ED nurses in the selection of initial NIV settings was not influenced by ED location, patient type or triage category.

Conclusions

Acute exacerbations of CPO and COPD were the most common indications for NIV. Clinicians demonstrated a preference for NIPPV for all patient aetiologies except ACPO. Responsibility for NIV management was shared by ED nurses and physicians.     

The impact of the initial ventilatory strategy on survival in hematological patients with acute hypoxemic respiratory failure

Purpose

The aim of this study was to assess the impact of the 3 types of initial respiratory support (noninvasive positive pressure ventilation vs invasive positive pressure ventilation vs supplemental oxygen only) in hematological patients with acute hypoxemic respiratory failure (ARF).

Materials and Methods

This study is a retrospective analysis of a cohort of hematological patients admitted to the intensive care unit (ICU) of a tertiary care hospital between January 1, 2002, and June 30, 2006.

Results

One hundred thirty-seven hematological patients were admitted at the ICU with ARF (defined as Pao₂/Fio₂ <200): within the first 24 hours, 24 and 67 patients received noninvasive positive pressure ventilation and invasive positive pressure ventilation, respectively, and 46 received supplemental oxygen only. Intensive care unit mortality in the 3 patient categories was 71%, 63%, and 32%, respectively (P = .001), and in-hospital mortality was 75%, 80%, and 47%, respectively (P = .001). In multivariate regression analysis, increasing cancer-specific severity-of-illness score upon admission and more organ failure after 24 hours of ICU admission, but not the type of initial respiratory support, were significantly associated with ICU or in-hospital mortality.

Conclusions

Intensive care unit and in-hospital mortality in our population of hematological patients with hypoxemic ARF was determined by severity of illness and not by the type of initial respiratory support.     

Outcomes of cardiopulmonary resuscitation for patients on vasopressors or inotropes: A pilot study

Hypothesis

Outcomes of critically ill patients who receive cardiopulmonary resuscitation (CPR) are poor, and the subgroup on vasopressors or inotropes before cardiopulmonary arrest (CPA) rarely survives.

Setting

The setting of the study was a critical care unit of a 350-bed community teaching hospital.

Study Design

This was a retrospective, cohort study.

Methods

A retrospective review was performed of medical records of all patients, identified through medical billing and hospital committee records, who received CPR for CPA in a critical care unit.

Results

Of 83 patients, with an average age of 66 years, 14 (17%) survived to hospital discharge. Patients with pulseless electrical activity and asystole were significantly less likely to survive (9% and none, respectively; P = .0001). Only 2 (4%) of 55 critically ill patients receiving vasopressors before CPR survived, whereas 12 of 28 patients not on vasopressors survived (P < .0001). Although mechanical ventilation just before CPR was highly associated with administration of vasopressors, ventilation was not significantly associated with mortality (P = .13). Mortality of patients on vasopressors was higher for both mechanically ventilated (95% vs 33%, P < .001) and spontaneously breathing (100% vs 64%, P = .02) patients. In multiple logistic regression analyses, administration of vasopressors was the only variable independently associated with in-hospital mortality (odds ratio, 35.1; 95% confidence interval = 4.1-304.3).

Conclusions

Survival of patients requiring CPR during critical care admission was 17%. Very few patients survived who required vasopressors or inotropes immediately before CPA. This study is limited significantly by its retrospective design and small cohort, and so this question should be reexamined in a larger study.     

A 5-year observational study of lung-protective ventilation in the operating room: A single-center experience

Purpose

We assessed the evolution of lung-protective ventilation strategies during anesthesia and identified factors associated with the selection of a nonprotective ventilation strategy.

Methods

This retrospective observational study covered a 5-year period from March 2006 to March 2011. It included 45?575 adult patients who underwent intubation de novo in the operating room. We considered a tidal volume (V_T) greater than 10 mL/kg of ideal body weight (IBW) and/or positive end-expiratory pressure (PEEP) less than 5 cm H₂O as not lung protective. We evaluated the use of nonprotective ventilation strategies over time in men and women, by American Society of Anesthesiologists classification, and for elective vs emergent surgery.

Results

Over the duration of the study, there was a significant reduction in the percentage of patients receiving a V_T greater than 10 mL/kg IBW (28.5%-16.3%, P < .001), zero PEEP (27.5%-18.2%, P < .001), and V_T greater than 10 mL/kg IBW with PEEP less than 5 cm H₂O (13.4%-8.0%, P < .001). The odds of receiving nonprotective ventilation were greater for women than for men, in the first year compared with the last year, and for elective compared with emergent surgery.

Conclusion

Although use of nonprotective ventilation decreased over time, an important percentage of patients continue to receive nonprotective ventilation.     

How do older ventilated patients fare? A survival/functional analysis of 641 ventilations

Background

The outcome of mechanical ventilation in elderly patients should be evaluated by integrating survival rates with functional state over time after the ventilation episode.

Objectives

The aim of this study was to measure the survival rate and functional state of elderly ventilated patients and to present an integrated analysis of both outcome measures.

Methods

This is a prospective observational, noninterventional study of 641 invasive medical ventilations of elderly (65+ years) patients in medical wards and intensive care units.The functional state, by the Functional Independence Measure scale, was measured before hospitalization, at discharge from the hospital, and 1 year later.

Results

Survival rates at the end of hospitalization and 3, 6, and 12 months later were 33%, 28%, 25%, and 22%, respectively. According to a combined survival/functional analysis, only 11% of all ventilated elderly patients were doing well (Functional Independence Measure scale score, ≥90) a year after the hospitalization. The rates for this condition ranged from 23% for acute exacerbation of chronic obstructive pulmonary disease to 0% for stroke and hospital-acquired pneumonia.

Conclusions

In elderly patients treated with mechanical ventilation, the outcomes in the period immediately after ventilation and later on are poor. In this group of patients, functional outcomes should be integrated with survival analysis for a meaningful assessment of the outcomes of treatment with mechanical ventilation to provide patients, families, practitioners, and society with reliable information on which life or death decisions can be based.     

Predictors of mortality of mechanically ventilated patients in internal medicine wards

Purpose

Budget restrictions have led to shortage of intensive care unit (ICU) beds in several countries. Consequently, ventilated patients are often kept on the wards. This study examined survival likelihood among patients ventilated on the wards and the predictive value of commonly used severity-of-illness scores.

Methods

This study is a prospective observation and characterization of consecutive, mechanically ventilated patients in 3 internal medicine wards of a single hospital who were denied ICU admission. Outcome measures are as follows: 28-day mortality, survival to hospital discharge, and 3 months postdischarge.

Results

Eighty-six patients were examined. The patients were 78.9 ± 8.9 years old; 53% were independent preadmission. Respiratory insufficiency due to infection was the main reason for mechanical ventilation (58%). Charlson and acute physiology scores (APS) averaged 4 ± 2.2 and 91.8 ± 26.7, respectively. Twenty-eight-day mortality was 71%, whereas in-hospital mortality was 74% and 3 months postdischarge mortality was 79%. Survivors were significantly younger than nonsurvivors (74.4 ± 8.5 years vs 80.4 ± 8.6 years, P < .01), were more likely to be ventilated for cardiac causes (41% vs 11%, P = .04), and had significantly higher initial mean blood pressure (79.4 mm Hg vs 58.2 mm Hg, P = .02) and blood albumin levels (29.8 g/L vs 25.7 g/L, P = .05). Death rate was 10 times more likely, with an APS greater than 90 on the day of intubation as compared with an APS less than 90.

Conclusion

Mortality in patients ventilated on the ward was high, especially in the subgroup of patients with an APS score greater than 90. The early calculation of APS may assist in focusing therapeutic efforts on patients with better survival chances.     

Face Mask Ventilation: A Comparison of Three Techniques

Background

There are multiple techniques for face-mask (FM) ventilation. To our knowledge, the one-handed vs. two-handed C-E technique has been compared in children and adults, but no studies have compared the various two-handed methods.

Objective

To compare the effectiveness of mask seal using three different FM techniques on a model intended to simulate difficult FM ventilation and measure ventilation performance.

Methods

This was a prospective randomized study of health care providers. A standard airway-training mannequin was modified to produce variable airway resistance and allow measurements of ventilation volume and pressure. Each subject performed FM ventilation for 3 min per technique (30 breaths) in a randomized order. Median exhaled tidal volume and proximal peak flow pressure were determined and compared.

Results

Seventy subjects were enrolled. Both two-handed ventilation techniques were more effective than the one-handed technique by both volume and pressure measurements. The one-handed C-E technique yielded a median volume of 428.4 mL, vs. the two-handed C-E technique with 550.8 mL, and the two-handed V-E technique with 538 mL (p < 0.001). Peak pressure measurements revealed a median of 54.6 cm H₂O for the one-handed C-E technique, 66 cm H₂O for the two-handed C-E technique, and 66.6 cm H₂O for the two-handed V-E technique (p < 0.001). There was not a difference between the various two-handed techniques.

Conclusions

This model for FM ventilation is able to differentiate the efficacy of FM techniques. Both two-handed ventilation methods were superior to one-handed ventilation, both of which should perhaps be included in airway training for health care providers.