Severe Cardiogenic Pulmonary Edema Research Articles

Continuous positive airway pressure plus low flow oxygen versus usual care of severe acute cardiogenic pulmonary edema in the pre-hospital setting: A randomised controlled trial

Background: Acute cardiogenic pulmonary edema (ACPE) is characterized by acute breathlessness and hypoxia and is associated with poor prognosis. Standard pre-hospital management of ACPE includes high-flow oxygen, nitroglycerin and, in severe cases, assisted ventilation. Patients with ACPE can be supported with newer modalities of non-invasive ventilation, specifically continuous positive airway pressure (CPAP). The aim of this study was to determine whether patients with ACPE treated with CPAP plus low-flow oxygen pre-hospitally have a lower mortality rate than those treated conventionally. Methods: This study was a pre-hospital randomised, non-blinded controlled trial conducted July 2009–July 2010. Included were all participants transported by ambulance and admitted to the Royal Hobart Hospital, Tasmania, Australia. The study population was consecutive persons ≥18 years of age with sudden onset of severe respiratory distress, diagnosed as ACPE. Patients were included if they required ventilatory assistance. Patients required a GCS >12 and blood pressure >90 mmHg systolic to safely receive CPAP. The primary outcome was pre- or in-hospital mortality. Results: In total, 50 patients were enrolled with mean age of 79.8 (±11.9) years. There were two deaths (8.3%) in the CPAP arm and nine (34.6%) in the control arm (RR, −0.24; 95% CI, 0.06–1.00; p=0.051) with a number needed to treat of 4. CPAP plus low-flow oxygen was significantly less likely to result in respiratory acidosis (mean difference in pH, −0.11; 95% CI, −0.04–−0.17; p=0.002), with elevated pCO2 (mean difference, −10.0 mmHg; 95% CI, −19.2–−0.78; p=0.026). The length of hospital stay was significantly shorter in the surviving patients who received CPAP (ratio of means, 0.45; 95% CI, 0.29–0.70; p≤0.001). Discussion: This study, which provides interim results due to early termination of the trial, shows CPAP in the pre-hospital setting for ACPE is practicable and is associated with improved patient outcomes.

Acidemia in severe acute cardiogenic pulmonary edema treated with noninvasive pressure support ventilation: a single-center experience.

In clinical practice, acidotic patients with acute cardiogenic pulmonary edema (ACPE) are commonly considered more severe in comparison with nonacidotic patients, and data on the outcome of these patients treated with noninvasive pressure support ventilation (NIV) are lacking.The present investigation was aimed at assessing whether acidosis on admission (pH < 7.35) was associated with adverse outcome in 65 consecutive patients with ACPE treated with NIV and admitted to our Intensive Cardiac Care Unit (ICCU).In our population, 28 patients were acidotic (28 of 65, 43.1%), whereas 41 patients were not (37 of 65, 56.9%). According to the Repeated Measures General Linear Model, pCO2 values significantly changed throughout the 2-h NIV treatment (P = 0.019) in both groups (P = 0001). In acidotic patients, pCO2 significantly decreased (51.9 ± 15.3 → 47.0 ± 12.8 → 44.8 ± 12.7), whereas they increased in the nonacidotic subgroup (36.8 ± 6.5 → 36.9 ± 7.2 → 37.6 ± 6.4). No difference was observed in intubation rate between acidotic (eight patients, 28.6%) and nonacidotic patients (12 patients, 32.4%) (P = 0.738). In-ICCU mortality rate did not differ between (13 patients, 35.1%) and nonacidotic patients (nine patients, 32.1%) (P = 0.801).Our data strongly suggest that in patients with severe ACPE treated with NIV, the presence of acidosis is not associated with adverse outcomes (early mortality and intubation rates) in these patients.

High flow on the rise-pediatric perspectives on the FLORALI trial.

Over the last decade, noninvasive positive pressure ventilation (NIV) has been increasingly used in adult and pediatric medicine to reduce the lung injuries, pneumonia, and denutrition associated with mechanical ventilation, which is implicated in the high mortality observed in these patients (1). For adults with acute exacerbations of chronic obstructive pulmonary disease (2) or severe cardiogenic pulmonary edema (3), it is now an evidence-based practice. It may also be an effective strategy in the perioperative period, provided that patients are carefully selected (4). The benefits of NIV have nevertheless not been clearly established in clinical situations like status asthmaticus (5) or acute hypoxemic respiratory failure (AHRF) or as a means to facilitate earlier extubation (6). The conflicting results for ARHF may be due to its several etiologies, which has prompted new trials with less heterogeneous patient groups (7).

Severe but not mild hypercapnia affects the outcome in patients with severe cardiogenic pulmonary edema treated by non-invasive ventilation

BackgroundPatients with severe cardiogenic pulmonary edema (CPE) are frequently hypercapnic, possibly because of associated underlying chronic lung disease (CLD). Since hypercapnia has been associated with outcome, we aimed to identify factors associated to hypercapnia and its role on outcome of patients with CPE and no underlying CLD.MethodsObservational cohort study using data prospectively collected over a 3-year period. After excluding patients with any CLD or obstructive sleep apneas, all patients treated by non-invasive ventilation (NIV) for severe CPE were included. Hypercapnia was defined as PaCO2 >45 mmHg and non-rapid favorable outcome was defined as the need for intubation or continuation of NIV for more than 48 h.ResultsAfter excluding 60 patients with underlying CLD or sleep apneas, 112 patients were studied. The rates of intubation and of prolonged NIV were 6.3 % (n = 7) and 21.4 % (n = 24), respectively. Half of the patients (n = 56) had hypercapnia upon admission. Hypercapnic patients were older, more frequently obese, and were more likely to have a respiratory tract infection than non-hypercapnic patients. Hypercapnia had no influence on intubation rate or the need for prolonged NIV. However, patients with severe hypercapnia (PaCO2 >60 mmHg) needed longer durations of NIV and intensive care unit (ICU) stay than the others.ConclusionsAmong the patients admitted for severe CPE without CLD, half of them had hypercapnia at admission. Hypercapnic patients were older and more frequently obese but their outcome was similar compared to non-hypercapnic patients. Patients with severe hypercapnia needed longer durations of NIV than the others without increase in intubation rate.

Diuretic, opiate and nitrate use in severe acidotic acute cardiogenic pulmonary oedema: analysis from the 3CPO trial

Drug treatments for acute cardiogenic pulmonary oedema (ACPO) have not been rigorously evaluated and recent observational data suggests some agents are related to poorer outcome. We aimed to examine the effect of treatment with diuretics, nitrates and opiates on 7-day mortality, acidosis and respiratory distress in UK Emergency Department (ED) patients with severe acidotic pulmonary oedema. Analysis of data from the 3CPO trial; a multicentre randomized controlled trial. Data were analysed from patients recruited with severe acidotic pulmonary oedema to the 3CPO trial in 26 UK EDs between 2003 and 2007. The effects of these treatments on 7-day mortality, improvement in acidosis (pH change between baseline and 1 h) and improvement in respiratory distress (patient measured breathlessness using a Visual Analogue Score between baseline and 1 h) were tested using univariate logistic regression analysis, and a regression model used to adjust for confounding baseline differences. Nitrates were given to 947/1048 (90.4%) patients, diuretics to 934/1049 (89.0%) patients and opiates to 541/1052 patients (51.4%). Adjusted analysis showed that opiate treatment was associated with less improvement in acidosis [difference in improvement in pH -0.022, 95% confidence interval (CI) -0.014 to -0.030, P < 0.001], but no difference in mortality or improvement in respiratory distress. We found no evidence that nitrate or diuretic use were associated with any difference in mortality, improvement in acidosis or respiratory distress. Opiate use is associated with less improvement in acidosis during initial treatment and may attenuate effective treatment of severe acidotic ACPO.

The Development of a Simple Risk Score to Predict Early Outcome in Severe Acute Acidotic Cardiogenic Pulmonary Edema

Background— Acute cardiogenic pulmonary edema is a common medical emergency with high early mortality. Initial clinical assessment would benefit from accurate mortality prediction. We aimed to develop a simple clinical score based on presenting characteristics that would predict 7-day mortality in patients with acute cardiogenic pulmonary edema. Methods and Results— We used data from patients recruited to the 3CPO trial (a pragmatic multicenter trial comparing continuous positive airway pressure, noninvasive positive pressure ventilation, and standard oxygen therapy in emergency department patients with acute cardiogenic pulmonary edema) to investigate the association between baseline characteristics and 7-day mortality. Factors associated with mortality ( P &lt;0.1) were entered into a multivariable model. Independent predictors of mortality from the multivariable model ( P &lt;0.05) were assigned integer weights based on their coefficients and incorporated into a risk score. The discriminant ability of the score was tested by receiver operator characteristic analysis. Data from 1069 patients (78±10 years; 43% men; 7-day mortality, 9.6%) were analyzed. Multivariable analysis identified age ( P =0.003), systolic blood pressure ( P &lt;0.001), and Glasgow Coma Scale motor component dichotomized and simplified to the ability to obey commands or not ( P =0.02) as the only independent predictors of 7-day mortality. These were weighted and used to develop a risk score ranging from 0 (7-day mortality, 1.9%; 95% CI, 0.8 to 4.5) to 7 (7-day mortality, 100%; 95% CI, 34.2 to 100). Receiver operator characteristic analysis demonstrated good risk prediction with a c-statistic of 0.794 (95% CI, 0.745 to 0.843). A simplified 3-point score with no weighting had a c-statistic of 0.754 (95% CI, 0.701 to 0.807). Conclusions— A simple clinical score based on age, systolic blood pressure, and the ability to obey commands predicts early mortality in patients with acute cardiogenic pulmonary edema. Clinical Trial Registration— clinicaltrials.gov Identifier: ISRCTN077448447.

A multicentre randomised controlled trial of the use of continuous positive airway pressure and non-invasive positive pressure ventilation in the early treatment of patients presenting to the emergency department with severe acute cardiogenic pulmonary oedema: the 3CPO trial

To determine whether non-invasive ventilation reduces mortality and whether there are important differences in outcome by treatment modality. Multicentre open prospective randomised controlled trial. Patients presenting with severe acute cardiogenic pulmonary oedema in 26 emergency departments in the UK. Inclusion criteria were age > 16 years, clinical diagnosis of acute cardiogenic pulmonary oedema, pulmonary oedema on chest radiograph, respiratory rate > 20 breaths per minute, and arterial hydrogen ion concentration > 45 nmol/l (pH < 7.35). Patients were randomised to standard oxygen therapy, continuous positive airway pressure (CPAP) (5-15 cmH2O) or non-invasive positive pressure ventilation (NIPPV) (inspiratory pressure 8-20 cmH2O, expiratory pressure 4-10 cmH2O) on a 1:1:1 basis for a minimum of 2 hours. The primary end point for the comparison between NIPPV or CPAP and standard therapy was 7-day mortality. The composite primary end point for the comparison of NIPPV and CPAP was 7-day mortality and tracheal intubation rate. Secondary end points were breathlessness, physiological variables, intubation rate, length of hospital stay and critical care admission rate. Economic evaluation took the form of a cost-utility analysis, taken from an NHS (and personal social services) perspective. In total, 1069 patients [mean age 78 (SD 10) years; 43% male] were recruited to standard therapy (n = 367), CPAP [n = 346; mean 10 (SD 4) cmH2O] or NIPPV [n = 356; mean 14 (SD 5)/7 (SD 2) cmH2O]. There was no difference in 7-day mortality for standard oxygen therapy (9.8%) and non-invasive ventilation (9.5%; p = 0.87). The combined end point of 7-day death and intubation rate was similar, irrespective of non-invasive ventilation modality (CPAP 11.7% versus NIPPV 11.1%; p = 0.81). Compared with standard therapy, non-invasive ventilation was associated with greater reductions (treatment difference, 95% confidence intervals) in breathlessness (visual analogue scale score 0.7, 0.2-1.3; p = 0.008) and heart rate (4/min, 1-6; p = 0.004) and improvement in acidosis (pH 0.03, 0.02-0.04; p < 0.001) and hypercapnia (0.7 kPa, 0.4-0.9; p < 0.001) at 1 hour. There were no treatment-related adverse events or differences in other secondary outcomes such as myocardial infarction rate, length of hospital stay, critical care admission rate and requirement for endotracheal intubation. Economic evaluation showed that mean costs and QALYs up to 6 months were 3023 pounds and 0.202 for standard therapy, 3224 pounds and 0.213 for CPAP, and 3208 pounds and 0.210 for NIPPV. Modelling of lifetime costs and QALYs produced values of 15,764 pounds and 1.597 for standard therapy, 17,525 pounds and 1.841 for CPAP, and 17,021 pounds and 1.707 for NIPPV. These results suggest that both CPAP and NIPPV accrue more QALYs but at higher cost than standard therapy. However, these estimates are subject to substantial uncertainty. Non-invasive ventilatory support delivered by either CPAP or NIPPV safely provides earlier improvement and resolution of breathlessness, respiratory distress and metabolic abnormality. However, this does not translate into improved short- or longer-term survival. We recommend that CPAP or NIPPV should be considered as adjunctive therapy in patients with severe acute cardiogenic pulmonary oedema in the presence of severe respiratory distress or when there is a failure to improve with pharmacological therapy. Current Controlled Trials ISRCTN07448447.

Continuous positive airway pressure vs. proportional assist ventilation for noninvasive ventilation in acute cardiogenic pulmonary edema

To compare continuous positive airway pressure (CPAP) and proportional assist ventilation (PAV) as modes of noninvasive ventilatory support in patients with severe cardiogenic pulmonary edema. A prospective multicenter randomized study in the medical ICUs of three teaching hospitals. Thirty-six adult patients with cardiogenic pulmonary edema (CPA) with unresolving dyspnea, respiratory rate above 30/min and/or SpO2 above 90% with O2 higher than 10 l/min despite conventional therapy with furosemide and nitrates. Patients were randomized to undergo either CPAP (with PEEP 10 cmH2O) or PAV (with PEEP 5-6 cmH2O) noninvasive ventilation through a full face mask and the same ventilator. The main outcome measure was the failure rate as defined by the onset of predefined intubation criteria, severe arrythmias or patient's refusal. On inclusion CPAP (n=19) and PAV (n=17) groups were similar with regard to age, sex ratio, type of heart disease, SAPS II, physiological parameters (mean arterial pressure, heart rate, blood gases), amount of infused nitrates and furosemide. Failure was observed in 7 (37%) CPAP and 7 (41%) PAV patients. Among these, 4 (21%) CPAP and 5 (29%) PAV patients required endotracheal intubation. Changes in physiological parameters were similar in the two groups. Myocardial infarction and ICU mortality rates were strictly similar in the two groups. In the present study PAV was not superior to CPAP for noninvasive ventilation in severe cardiogenic pulmonary edema with regard to either efficacy and tolerance.

Prehospital noninvasive pressure support ventilation for acute cardiogenic pulmonary edema

Severe acute cardiogenic pulmonary edema (ACPE) can successfully be treated with noninvasive pressure support ventilation (NIPSV) in a clinical setting. Whether prehospital NIPSV starting early at patients' home and being continued until hospital arrival is feasible and improves ACPE emergency care is examined in this study. End points of the study were oxygen saturation at hospital admission and clinical outcome. Twenty-three patients suffering from severe cardiac pulmonary edema with severe dyspnea, an oxygen saturation of less than 90% and basal rales were included in this controlled prospective randomized trial. All patients received standard medical treatment and 10 patients were additionally treated with NIPSV (pressure support level, 12 cmH2O; positive endexpiratory pressure, 5 cmH2O; FiO2, 0.6) whereas the other patients received oxygen (8 l/min) via Venturi face mask. Improvement in oxygen saturation was significantly faster in the NIPSV group and oxygen saturation was higher at the time of the hospital admission (NIPSV=97.3+/-0.8%; standard=89.5+/-2.7%, P=0.002). A trend toward higher troponin T levels was seen in the standard treatment group. The need for intensive care treatment did not differ, and one patient of each treatment group died in hospital. No complications were noted during the treatment with NIPSV. Prehospital NIPSV is feasible and able to improve emergency management of ACPE.

Peripheral line dead space: an unrecognised phenomenon?

Objective: To determine if peripheral intravenous cannula dead space is taken into account when setting up intravenous infusions (in particular nitrate infusions) in the emergency department. Method: A postal survey...

Transient Leukocytopenia Associated with a Steep Surge of Pro-inflammatory Cytokines in a Patient with Severe Cardiogenic Pulmonary Edema

Leukocytopenia can be caused by depressed production, increased peripheral destruction, or excessive peripheral pooling. Leukocyte margination is one of the mechanisms responsible for excessive peripheral pooling. A reversible leukocyte margination is caused by an increase in pro-inflammatory cytokines. However, there are limited data for this phenomenon in clinical conditions. We describe a case of unexpected transient leukocytopenia after exchanging an extracorporeal membrane oxygenation (ECMO) system used to treat severe cardiogenic pulmonary edema. To assess the cause of the leukocytopenia, the serum concentrations of pro-inflammatory cytokines and selectins were measured. The concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-8 were markedly, but transiently, elevated in relation to the leukocytopenia. The transient leukocytopenia with pulmonary margination appeared to be caused by a steep surge of pro-inflammatory cytokines stimulated by hypoxia/reoxygenation during the exchange of the ECMO system. This case may suggest the mechanisms responsible for leukocytopenia in the clinical entity referred to as "systemic inflammatory response syndrome"

Does Continuous Positive Airway Pressure by Face Mask Improve Patients With Acute Cardiogenic Pulmonary Edema Due to Left Ventricular Diastolic Dysfunction?

Continuous positive airway pressure (CPAP) by face mask is an effective method of treating severe cardiogenic pulmonary edema (CPE). However, to our knowledge, no study has provided a precise evaluation of the effects of CPAP on cardiac function in patients presenting with CPE and preserved left ventricular (LV) function. Prospective observational clinical study. A 14-bed, medical ICU at a university hospital. Nine consecutive patients presenting with hypoxemic acute CPE. All patients were selected for 30 min of CPAP with 10 cm H(2)O by mask with fraction of inspired oxygen adjusted for a cutaneous saturation > 90%. Doppler echocardiography was performed before CPAP application and during the last 10 min of breathing with CPAP. Two-tailed, paired t-tests were used to compare data recorded at baseline (oxygen alone) and after CPAP. Four patients presented CPE with preserved left ventricular (LV) function (a preserved LV ejection fraction [LVEF] > 45%, and/or aortic velocity time integral > 17 cm in the absence of aortic stenosis or hypertrophic cardiomyopathy). Oxygenation and ventilatory parameters were improved by CPAP in all patients. Hemodynamic monitoring and Doppler echocardiographic analysis demonstrated that in patients with preserved LV systolic function, mean arterial pressure and LV end-diastolic volume were decreased significantly by CPAP (p < 0.04). In patients with LV systolic dysfunction, CPAP improved LVEF (p < 0.05) and decreased LV end-diastolic volume (p = 0.001) significantly. CPAP improves oxygenation and ventilatory parameters in all kinds of CPE. In patients with preserved LV contractility, the hemodynamic benefit of CPAP results from a decrease in LV end-diastolic volume (preload).

Randomized, prospective trial of oxygen, continuous positive airway pressure, and bilevel positive airway pressure by face mask in acute cardiogenic pulmonary edema*

To compare the effects of oxygen, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (bilevel-PAP) on the rate of endotracheal intubation in patients with acute cardiogenic pulmonary edema. Randomized, controlled trial. Tertiary hospital emergency room. We randomly assigned 80 patients with severe cardiogenic acute pulmonary edema into three treatment groups. Patients were followed for 60 days after the randomization. Oxygen applied by face mask, CPAP, and bilevel-PAP. The rate of endotracheal intubation as well as vital signs and blood gases was recorded during the first 24 hrs. Mortality was evaluated at 15 days, at 60 days, and at hospital discharge. Complications related to respiratory support were evaluated before hospital discharge. Treatment with CPAP or bilevel-PAP resulted in significant improvement in the PaO2/FiO2 ratio, subjective dyspnea score, and respiratory and heart rates compared with oxygen therapy. Endotracheal intubation was necessary in 11 of 26 patients (42%) in the oxygen group but only in two of 27 patients (7%) in each noninvasive ventilation group (p = .001). There was no increase in the incidence of acute myocardial infarction in the CPAP or bilevel-PAP groups. Mortality at 15 days was higher in the oxygen than in the CPAP or bilevel-PAP groups (p < .05). Mortality up to hospital discharge was not significantly different among groups (p = .061). Compared with oxygen therapy, CPAP and bilevel-PAP resulted in similar vital signs and arterial blood gases and a lower rate of endotracheal intubation. No cardiac ischemic complications were associated with either of the noninvasive ventilation strategies.

Non-Invasive Pressure Support Ventilation in Patients with Respiratory Failure due to Severe Acute Cardiogenic Pulmonary Edema

Background: Recent studies suggest the use of non-invasive pressure support ventilation (NIPSV) in patients with acute cardiogenic pulmonary edema (ACPE). However, it remains unclear whether all patients with ACPE benefit from NIPSV. Objectives: To investigate short-term effects of NIPSV on respiratory, hemodynamic and oxygenation parameters in patients with respiratory failure due to severe ACPE and to identify factors predicting the need for intubation and in-hospital mortality. Methods: In a prospective, uncontrolled, open study, 28 patients admitted with signs and symptoms of severe respiratory distress due to ACPE were given NIPSV in addition to standardized pharmacological treatment. Physiological parameters were obtained before and after NIPSV, and intubation rate and in-hospital mortality were recorded. Results: NIPSV increased arterial oxygenation from paO₂ 54.2 ± 12.4 to 76.9 ± 12.6 mm Hg (p = 0.0001) and decreased respiratory frequency from 40.1 ± 8.2 to 22.4 ± 4.9 breaths/min (p = 0.0001). Significant improvements were also noted for heart rate, blood pressure and the paO₂/FiO₂ ratio. Four patients (14%) required intubation despite NIPSV. Patients who required intubation had lower paCO₂ levels (p = 0.0002), lower serum bicarbonate concentrations (p = 0.04) and lower systolic blood pressure (p = 0.045) than patients who were successfully treated with NIPSV. Eight patients (28.5%) died during hospitalization. In patients with a paCO₂ ≤35 mm Hg on admission, the in-hospital mortality was 87%, but in patients with a paCO₂ >35 mm Hg the in-hospital mortality was 6%. Conclusions: NIPSV improves oxygenation and alleviates respiratory distress in patients with respiratory failure due to severe ACPE. However, a subgroup of patients with hypocapnia on admission might have a poor prognosis, with a higher risk of intubation and in-hospital mortality.

Secular trends in nosocomial infections and mortality associated with noninvasive ventilation in patients with exacerbation of COPD and pulmonary edema.

Randomized controlled trials have shown that the use of noninvasive ventilation (NIV) reduces the need for endotracheal intubation and invasive mechanical ventilation and reduces complication rates and mortality in selected groups of patients. But whether these benefits translate to a clinical setting is unclear. To evaluate longitudinally the routine implementation of NIV and its effect on patients admitted to the intensive care unit (ICU) with acute exacerbation of chronic obstructive pulmonary disease (COPD) or severe cardiogenic pulmonary edema (CPE). Retrospective, observational cohort study using prospectively collected data from January 1, 1994, through December 31, 2001. A 26-bed medical intensive care unit (ICU) of a French university referral hospital. A cohort of 479 consecutive patients ventilated for acute exacerbation of COPD or CPE. The ICU mortality and incidence rates of ICU-acquired infections. A significant increase in NIV use and a concomitant decrease in mortality and ICU-acquired infection rates were observed over the study years. With adjustment for relevant covariates and propensity scores, NIV was identified as an independent factor linked with a reduced risk of death in the cohort (odds ratio [OR], 0.37; 95% confidence interval [CI], 0.18-0.78), whereas a high severity score on admission (OR, 1.05; 95% CI, 1.01-1.10) and the occurrence of a nosocomial infection (OR, 3.08; 95% CI, 1.62-5.84) were independently associated with death. Rates of ICU-acquired pneumonia decreased from 20% in 1994 to 8% in 2001 (P =.04). Implementing routine use of NIV in critically ill patients with acute exacerbation of COPD or severe CPE was associated with improved survival and reduction of nosocomial infections.

Risk factors for intubation as a guide for noninvasive ventilation in patients with severe acute cardiogenic pulmonary edema.

Noninvasive ventilation may reduce the endotracheal intubation rate in patients with acute cardiogenic pulmonary edema. However, criteria for selecting candidates for this technique are not well established. We analyzed a cohort of patients with severe acute cardiogenic pulmonary edema managed by conventional therapy to identify risk factors for intubation. These factors were used as guide for indications for noninvasive ventilation. Observational cohort registry in the ICU and emergency and cardiology departments in a community teaching hospital. . 110 consecutive patients with acute cardiogenic pulmonary edema, 80 of whom received conventional oxygen therapy. Physiological measurements and blood gas samples registered upon admission. Twenty-one patients (26%) treated with conventional oxygen therapy needed intubation. Acute myocardial infarction, pH below 7.25, low ejection fraction (<30%), hypercapnia, and systolic blood pressure below 140 mmHg were independent predictors for intubation. Conversely, systolic blood pressure of 180 mmHg or higher showed to be a protective factor since only two patients with this blood pressure value required intubation (8%)], both presenting with a pH lower than 7.25. Considering systolic blood pressure lower than 180 mmHg, patients who showed hypercapnia presented a high intubation rate (13/21, 62%) whereas the rate of intubation in patients with normocapnia was intermediate (6/23, 26%). All normocapnic patients with pH less than 7.25 required intubation. No patient with hypocapnia was intubated regardless the level of blood pressure. Patients with pH less than 7.25 or systolic blood pressure less than 180 mmHg associated with hypercapnia should be promptly considered for noninvasive ventilation. With this strategy about 40% of the patients would be initially treated with this technique, which would involve nearly 90% of the patients that require intubation.

Cardiac and respiratory effects of continuous positive airway pressure and noninvasive ventilation in acute cardiac pulmonary edema

Continuous positive airway pressure (CPAP) is considered an effective nonpharmacologic method of treating patients with severe acute cardiogenic pulmonary edema. However, we hypothesized that bilevel noninvasive positive-pressure ventilation (NPPV), which combines both inspiratory pressure support and positive expiratory pressure, would unload the respiratory muscles and improve cardiac and hemodynamic function more effectively than CPAP. Randomized crossover study. Critical care unit, Raymond Poincaré Hospital. Six consecutive patients with acute cardiogenic pulmonary edema. Patients were sequentially treated with 5 cm H2O CPAP, 10 cm H2O CPAP, and NPPV in a random order. Cardiac and hemodynamic function and indexes of respiratory mechanics were measured at each treatment sequence. NPPV reduced the esophageal pressure swing and esophageal pressure-time product compared with baseline (p <.05). There was no reduction in esophageal pressure swing or esophageal pressure-time product with CPAP. NPPV and 10 cm H2O CPAP reduced the mean transmural right and left atrial filling pressures without a change in cardiac index. This study demonstrates that NPPV was more effective at unloading the respiratory muscles than CPAP in acute cardiogenic pulmonary edema. In addition, NPPV and 10 cm H2O CPAP produced a reduction in right and left ventricular preload, which suggests an improvement in cardiac performance.

Supports ventilatoires dans l’œdème aigu pulmonaire cardiogénique

In case of severe acute cardiogenic pulmonary edema (ACPE), the decision to intubate should be aimed at: 1) relaxing exhausted respiratory muscles; 2) improving ventilation and gas exchanges; and 3) improving left ventricular function, mainly by decreasing afterload, especially in case of congestive heart failure. The main indications of artificial ventilation in severe ACPE are acute asphyxic states, respiratory muscle exhaustion, coma, severe hemodynamic complications, and lack of improvement despite conventional therapy. If invasive artificial ventilation is still the reference technique for some authors, noninvasive ventilation, which has developed during recent years, has permitted bypassing intubation and its complications. In case of ACPE, the reference noninvasive ventilation is CPAP; the other methods, such as pressure support ventilation, have not yet proved a better efficacy.

Association of noninvasive ventilation with nosocomial infections and survival in critically ill patients.

Invasive life-support techniques are a major risk factor for nosocomial infection. Noninvasive ventilation (NIV) can be used to avoid endotracheal intubation and may reduce morbidity among patients in intensive care units (ICUs). To determine whether the use of NIV is associated with decreased risk of nosocomial infections and improved survival in everyday clinical practice among patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) or hypercapnic cardiogenic pulmonary edema (CPE). Matched case-control study conducted in the medical ICU of a French university hospital from January 1996 through March 1998. Fifty patients with acute exacerbation of COPD or severe CPE who were treated with NIV for at least 2 hours and 50 patients treated with mechanical ventilation between 1993 and 1998 (controls), matched on diagnosis, Simplified Acute Physiology Score II, Logistic Organ Dysfunction score, age, and no contraindication to NIV. Rates of nosocomial infections, antibiotic use, lengths of ventilatory support and of ICU stay, ICU mortality, compared between cases and controls. Rates of nosocomial infections and of nosocomial pneumonia were significantly lower in patients who received NIV than those treated with mechanical ventilation (18% vs 60% and 8% vs 22%; P<.001 and P =.04, respectively). Similarly, the daily risk of acquiring an infection (19 vs 39 episodes per 1000 patient-days; P =.05), proportion of patients receiving antibiotics for nosocomial infection (8% vs 26%; P =.01), mean (SD) duration of ventilation (6 [6] vs 10 [12] days; P =.01), mean (SD) length of ICU stay (9 [7] vs 15 [14] days; P =.02), and crude mortality (4% vs 26%; P =.002) were all lower among patients who received NIV than those treated with mechanical ventilation. Use of NIV instead of mechanical ventilation is associated with a lower risk of nosocomial infections, less antibiotic use, shorter length of ICU stay, and lower mortality. JAMA. 2000;284:2361-2367.

The use of noninvasive pressure support ventilation for severe respiratory insufficiency due to pulmonary oedema.

Experimental use of noninvasive pressure support ventilation (NIPSV) in patients with severe pulmonary oedema who would have been intubated if noninvasive ventilation were not available. Open, prospective, within patients non comparative study. Internal intensive care unit (11 beds) at a university hospital. 29 patients with severe respiratory distress and confirmed pulmonary oedema. NIPSV was applied via a tight fitting face mask delivering between 13 and 24 cm H2O inspiratory airway pressure and 2 to 8 cm H2O expiratory airway pressure. One patient required endotracheal intubation. Mean plethysmographic oxygen saturation rose significantly within 30 min from 73.8+/-11 to 90.3+/-5%, while the oxygen supply was reduced from 7.3+/-3.7 to 5.1+/-3 l/min. Mean pH increased significantly (p<0.01) from 7.22+/-0.1 before NIPSV to 7.31+/-0.07 after 60 min of NIPSV. Partial pressure of carbon dioxide was 62+/-18.5 mmHg but decreased significantly within 60 min to 48.4+/-11.5 mm Hg. Heart rate and-blood pressure stabilised continuously during the observation time. Mean duration of NIPSV was 6 h 9 min (range 60 min to 24 h). There were no serious side effects. Four patients died from underlying diseases between 1 and 28 days after NIPSV. NIPSV is a highly effective technique with which to treat patients with severe cardiogenic pulmonary oedema.