Original Articles Archives - Page 2 of 25 - Critical Care Science (CCS)
, Abstract
Rev Bras Ter Intensiva. 2019;31(4):474-482
DOI 10.5935/0103-507X.20190073
, To compare cardiac output measurements by transthoracic echocardiography and a pulmonary artery catheter in mechanically ventilated patients with high positive end-expiratory pressure. To evaluate the effect of tricuspid regurgitation.
Sixteen mechanically ventilated patients were studied. Cardiac output was measured by pulmonary artery catheterization and transthoracic echocardiography. Measurements were performed at different levels of positive end-expiratory pressure (10cmH2O, 15cmH2O, and 20cmH2O). The effect of tricuspid regurgitation on cardiac output measurement was evaluated. The intraclass correlation coefficient was studied; the mean error and limits of agreement were studied with the Bland-Altman plot. The error rate was calculated.
Forty-four pairs of cardiac output measurements were obtained. An intraclass correlation coefficient of 0.908 was found (p < 0.001). The mean error was 0.44L/min for cardiac output values between 5 and 13L/min. The limits of agreement were 3.25L/min and -2.37L/min. With tricuspid insufficiency, the intraclass correlation coefficient was 0.791, and without tricuspid insufficiency, 0.935. Tricuspid insufficiency increased the error rate from 32% to 52%.
In patients with high positive end-expiratory pressure, cardiac output measurement by transthoracic echocardiography is comparable to that with a pulmonary artery catheter. Tricuspid regurgitation influences the intraclass correlation coefficient. In patients with high positive end-expiratory pressure, the use of transthoracic echocardiography to measure cardiac output is comparable to invasive measures.
Abstract
Rev Bras Ter Intensiva. 2019;31(4):474-482
DOI 10.5935/0103-507X.20190073
, To compare cardiac output measurements by transthoracic echocardiography and a pulmonary artery catheter in mechanically ventilated patients with high positive end-expiratory pressure. To evaluate the effect of tricuspid regurgitation.
Sixteen mechanically ventilated patients were studied. Cardiac output was measured by pulmonary artery catheterization and transthoracic echocardiography. Measurements were performed at different levels of positive end-expiratory pressure (10cmH2O, 15cmH2O, and 20cmH2O). The effect of tricuspid regurgitation on cardiac output measurement was evaluated. The intraclass correlation coefficient was studied; the mean error and limits of agreement were studied with the Bland-Altman plot. The error rate was calculated.
Forty-four pairs of cardiac output measurements were obtained. An intraclass correlation coefficient of 0.908 was found (p < 0.001). The mean error was 0.44L/min for cardiac output values between 5 and 13L/min. The limits of agreement were 3.25L/min and -2.37L/min. With tricuspid insufficiency, the intraclass correlation coefficient was 0.791, and without tricuspid insufficiency, 0.935. Tricuspid insufficiency increased the error rate from 32% to 52%.
In patients with high positive end-expiratory pressure, cardiac output measurement by transthoracic echocardiography is comparable to that with a pulmonary artery catheter. Tricuspid regurgitation influences the intraclass correlation coefficient. In patients with high positive end-expiratory pressure, the use of transthoracic echocardiography to measure cardiac output is comparable to invasive measures.
, , Abstract
Rev Bras Ter Intensiva. 2019;31(4):483-489
DOI 10.5935/0103-507X.20190071
, , To describe the behavior of inspiratory resistance components when positive end-expiratory pressure (PEEP) increases in patients with acute respiratory distress syndrome under a protective ventilation strategy.
In volume-controlled mode, at 6mL/kg and constant flow, end-inspiratory occlusions were performed at 0, 5 10, 15 and 20cmH2O PEEP. Peak, initial and plateau pressure values were assessed, calculating the maximum, minimum and differential resistances. The results were compared by repeated measures analysis of variance (ANOVA) with post hoc Bonferroni correction, considering p < 0.05 significant.
The highest maximum resistance was observed at the lowest PEEP levels. The values for 10 and 15cmH2O PEEP significantly differed from those for 5 and 0cmH2O PEEP, whereas that for 20cmH2O PEEP only significantly differed from that for 0cmH2O PEEP (p < 0.05). The minimum resistance behaved similarly to the maximum resistance; the values for PEEP levels from 10cmH2O to 20cmH2O significantly differed from those for 0 and 5cmH2O PEEP (p < 0.05). Differential resistance showed the opposite variation to the maximum and minimum resistances. The only PEEP level that showed significant differences from 0 and 5cmH2O PEEP was 20cmH2O PEEP. Significant differences were also found between 15 and 5cmH2O PEEP (p < 0.05).
During protective ventilation in patients with acute respiratory distress syndrome, the maximum resistance of the respiratory system decreases with PEEP, reflecting the minimum resistance response, whereas differential resistance increases with PEEP.
Abstract
Rev Bras Ter Intensiva. 2019;31(4):483-489
DOI 10.5935/0103-507X.20190071
, , To describe the behavior of inspiratory resistance components when positive end-expiratory pressure (PEEP) increases in patients with acute respiratory distress syndrome under a protective ventilation strategy.
In volume-controlled mode, at 6mL/kg and constant flow, end-inspiratory occlusions were performed at 0, 5 10, 15 and 20cmH2O PEEP. Peak, initial and plateau pressure values were assessed, calculating the maximum, minimum and differential resistances. The results were compared by repeated measures analysis of variance (ANOVA) with post hoc Bonferroni correction, considering p < 0.05 significant.
The highest maximum resistance was observed at the lowest PEEP levels. The values for 10 and 15cmH2O PEEP significantly differed from those for 5 and 0cmH2O PEEP, whereas that for 20cmH2O PEEP only significantly differed from that for 0cmH2O PEEP (p < 0.05). The minimum resistance behaved similarly to the maximum resistance; the values for PEEP levels from 10cmH2O to 20cmH2O significantly differed from those for 0 and 5cmH2O PEEP (p < 0.05). Differential resistance showed the opposite variation to the maximum and minimum resistances. The only PEEP level that showed significant differences from 0 and 5cmH2O PEEP was 20cmH2O PEEP. Significant differences were also found between 15 and 5cmH2O PEEP (p < 0.05).
During protective ventilation in patients with acute respiratory distress syndrome, the maximum resistance of the respiratory system decreases with PEEP, reflecting the minimum resistance response, whereas differential resistance increases with PEEP.
, , Abstract
Rev Bras Ter Intensiva. 2019;31(4):490-496
DOI 10.5935/0103-507X.20190086
, , To evaluate the concordance between the modified NUTRIC and NUTRIC with C-reactive protein instruments in identifying nutritional risk patients and predicting mortality in critically ill patients. The risk of death in patient groups was also investigated according to nutritional risk and malnutrition detected by subjective global assessment.
A cohort study of patients admitted to an intensive care unit. Nutritional risk was assessed by modified NUTRIC and a version of NUTRIC with C-reactive protein. Subjective global assessment was applied to diagnose malnutrition. Kappa statistics were calculated, and an ROC curve was constructed considering modified NUTRIC as a reference. The predictive validity was assessed considering mortality in 28 days (whether in the intensive care unit or after discharge) as the outcome.
A total of 130 patients were studied (63.05 ± 16.46 years, 53.8% males). According to NUTRIC with C-reactive protein, 34.4% were classified as having a high score, while 28.5% of patients had this classification with modified NUTRIC. According to SGA 48.1% of patients were malnourished. There was excellent agreement between modified NUTRIC and NUTRIC with C-reactive protein (Kappa = 0.88, p < 0.001). The area under the ROC curve was equal to 0.942 (0.881 - 1.000) for NUTRIC with C-reactive protein. The risk of death within 28 days was increased in patients with high modified NUTRIC (HR = 1.827; 95%CI 1.029 - 3.244; p = 0.040) and NUTRIC with C-reactive protein (HR = 2.685; 95%CI 1.423 - 5.064; p = 0.002) scores. A high risk of death was observed in patients with high nutritional risk and malnutrition, independent of the version of the NUTRIC score applied.
An excellent agreement between modified NUTRIC and NUTRIC with C-reactive protein was observed. In addition, combining NUTRIC and subjective global assessment may increase the accuracy of predicting mortality in critically ill patients.
Abstract
Rev Bras Ter Intensiva. 2019;31(4):490-496
DOI 10.5935/0103-507X.20190086
, , To evaluate the concordance between the modified NUTRIC and NUTRIC with C-reactive protein instruments in identifying nutritional risk patients and predicting mortality in critically ill patients. The risk of death in patient groups was also investigated according to nutritional risk and malnutrition detected by subjective global assessment.
A cohort study of patients admitted to an intensive care unit. Nutritional risk was assessed by modified NUTRIC and a version of NUTRIC with C-reactive protein. Subjective global assessment was applied to diagnose malnutrition. Kappa statistics were calculated, and an ROC curve was constructed considering modified NUTRIC as a reference. The predictive validity was assessed considering mortality in 28 days (whether in the intensive care unit or after discharge) as the outcome.
A total of 130 patients were studied (63.05 ± 16.46 years, 53.8% males). According to NUTRIC with C-reactive protein, 34.4% were classified as having a high score, while 28.5% of patients had this classification with modified NUTRIC. According to SGA 48.1% of patients were malnourished. There was excellent agreement between modified NUTRIC and NUTRIC with C-reactive protein (Kappa = 0.88, p < 0.001). The area under the ROC curve was equal to 0.942 (0.881 - 1.000) for NUTRIC with C-reactive protein. The risk of death within 28 days was increased in patients with high modified NUTRIC (HR = 1.827; 95%CI 1.029 - 3.244; p = 0.040) and NUTRIC with C-reactive protein (HR = 2.685; 95%CI 1.423 - 5.064; p = 0.002) scores. A high risk of death was observed in patients with high nutritional risk and malnutrition, independent of the version of the NUTRIC score applied.
An excellent agreement between modified NUTRIC and NUTRIC with C-reactive protein was observed. In addition, combining NUTRIC and subjective global assessment may increase the accuracy of predicting mortality in critically ill patients.
, , Abstract
Rev Bras Ter Intensiva. 2019;31(4):497-503
DOI 10.5935/0103-507X.20190087
, , To evaluate whether electromyographical findings could predict intensive care unit mortality among mechanically ventilated septic patients under profound sedation.
A prospective cohort study that consecutively enrolled moderate-severe acute respiratory distress syndrome (partial pressure of oxygen/fraction of inspired oxygen < 200) patients who were ≥ 18 years of age, dependent on mechanical ventilation for ≥ 7 days, and under profound sedation (Richmond Agitation Sedation Scale ≤ -4) was conducted. Electromyographic studies of the limbs were performed in all patients between the 7th and the 10th day of mechanical ventilation. Sensory nerve action potentials were recorded from the median and sural nerves. The compound muscle action potentials were recorded from the median (abductor pollicis brevis muscle) and common peroneal (extensor digitorum brevis muscle) nerves.
Seventeen patients were enrolled during the seven months of the study. Nine patients (53%) had electromyographic signs of critical illness myopathy or neuropathy. The risk of death during the intensive care unit stay was increased in patients with electromyographical signs of critical illness myopathy or neuropathy in comparison to those without these diagnostics (77.7% versus 12.5%, log-rank p = 0.02).
Electromyographical signs of critical illness myopathy or neuropathy between the 7th and the 10th day of mechanical ventilation may be associated with intensive care unit mortality among moderate-severe acute respiratory distress syndrome patients under profound sedation, in whom clinical strength assessment is not possible.
Abstract
Rev Bras Ter Intensiva. 2019;31(4):497-503
DOI 10.5935/0103-507X.20190087
, , To evaluate whether electromyographical findings could predict intensive care unit mortality among mechanically ventilated septic patients under profound sedation.
A prospective cohort study that consecutively enrolled moderate-severe acute respiratory distress syndrome (partial pressure of oxygen/fraction of inspired oxygen < 200) patients who were ≥ 18 years of age, dependent on mechanical ventilation for ≥ 7 days, and under profound sedation (Richmond Agitation Sedation Scale ≤ -4) was conducted. Electromyographic studies of the limbs were performed in all patients between the 7th and the 10th day of mechanical ventilation. Sensory nerve action potentials were recorded from the median and sural nerves. The compound muscle action potentials were recorded from the median (abductor pollicis brevis muscle) and common peroneal (extensor digitorum brevis muscle) nerves.
Seventeen patients were enrolled during the seven months of the study. Nine patients (53%) had electromyographic signs of critical illness myopathy or neuropathy. The risk of death during the intensive care unit stay was increased in patients with electromyographical signs of critical illness myopathy or neuropathy in comparison to those without these diagnostics (77.7% versus 12.5%, log-rank p = 0.02).
Electromyographical signs of critical illness myopathy or neuropathy between the 7th and the 10th day of mechanical ventilation may be associated with intensive care unit mortality among moderate-severe acute respiratory distress syndrome patients under profound sedation, in whom clinical strength assessment is not possible.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):318-325
DOI 10.5935/0103-507X.20190057
To validate the "Checklist for Managing Critical Patients' Daily Awakening" instrument.
This was a descriptive study that used a quantitative approach for content validation using the Delphi method to obtain the consensus of experts who evaluated the instrument using a Likert scale. The validity index of each item of the instrument was calculated, with a minimum consensus parameter above 0.78.
Three Delphi rounds were required, starting with 29 experts and ending with 15 experts who were invited in person and via e-mail to participate in the study. Of the 15 items in the instrument, 13 had a content validity index > 0.78. The instrument maintained its attributes, and six items were reformulated without the need to exclude any of them. The validated items enabled the assessment of and decisions regarding the dimensions related to the level of sedation and agitation, vital signs, ventilatory parameters and pain. The instrument presented psychometric indicators with acceptable content validity.
The instrument proposed in the study exhibited content validity for most of its items and emerges as a practical strategy for the management of the daily interruption of sedation of critical patients.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):318-325
DOI 10.5935/0103-507X.20190057
To validate the "Checklist for Managing Critical Patients' Daily Awakening" instrument.
This was a descriptive study that used a quantitative approach for content validation using the Delphi method to obtain the consensus of experts who evaluated the instrument using a Likert scale. The validity index of each item of the instrument was calculated, with a minimum consensus parameter above 0.78.
Three Delphi rounds were required, starting with 29 experts and ending with 15 experts who were invited in person and via e-mail to participate in the study. Of the 15 items in the instrument, 13 had a content validity index > 0.78. The instrument maintained its attributes, and six items were reformulated without the need to exclude any of them. The validated items enabled the assessment of and decisions regarding the dimensions related to the level of sedation and agitation, vital signs, ventilatory parameters and pain. The instrument presented psychometric indicators with acceptable content validity.
The instrument proposed in the study exhibited content validity for most of its items and emerges as a practical strategy for the management of the daily interruption of sedation of critical patients.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):326-332
DOI 10.5935/0103-507X.20190041
To evaluate possible associations between nutritional risk and the clinical outcomes of critical patients admitted to an intensive care unit.
A prospective study was carried out with a cohort comprising 200 patients admitted to a university hospital intensive care unit. Nutritional risk was assessed with the NRS-2002 and NUTRIC scores. Patients with scores ≥ 5 were considered at high nutritional risk. Clinical data and outcome measures were obtained from patients' medical records. Multiple logistic regression analysis was used to calculate odds ratios and their respective 95% confidence intervals (for clinical outcomes).
This sample of critical patients had a mean age of 59.4 ± 16.5 years and 53.5% were female. The proportions at high nutritional risk according to NRS-2002 and NUTRIC were 55% and 36.5%, respectively. Multiple logistic regression models adjusted for gender and type of admission indicated that high nutritional risk assessed by the NRS-2002 was positively associated with use of mechanical ventilation (OR = 2.34; 95%CI 1.31 - 4.19; p = 0.004); presence of infection (OR = 2.21; 95%CI 1.24 - 3.94; p = 0.007), and death (OR = 1.86; 95%CI 1.01 - 3.41; p = 0.045). When evaluated by NUTRIC, nutritional risk was associated with renal replacement therapy (OR = 2.10; 95%CI 1.02 - 4.15; p = 0.040) and death (OR = 3.48; 95%CI 1.88 - 6.44; p < 0.001).
In critically ill patients, high nutritional risk was positively associated with an increased risk of clinical outcomes including hospital death.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):326-332
DOI 10.5935/0103-507X.20190041
To evaluate possible associations between nutritional risk and the clinical outcomes of critical patients admitted to an intensive care unit.
A prospective study was carried out with a cohort comprising 200 patients admitted to a university hospital intensive care unit. Nutritional risk was assessed with the NRS-2002 and NUTRIC scores. Patients with scores ≥ 5 were considered at high nutritional risk. Clinical data and outcome measures were obtained from patients' medical records. Multiple logistic regression analysis was used to calculate odds ratios and their respective 95% confidence intervals (for clinical outcomes).
This sample of critical patients had a mean age of 59.4 ± 16.5 years and 53.5% were female. The proportions at high nutritional risk according to NRS-2002 and NUTRIC were 55% and 36.5%, respectively. Multiple logistic regression models adjusted for gender and type of admission indicated that high nutritional risk assessed by the NRS-2002 was positively associated with use of mechanical ventilation (OR = 2.34; 95%CI 1.31 - 4.19; p = 0.004); presence of infection (OR = 2.21; 95%CI 1.24 - 3.94; p = 0.007), and death (OR = 1.86; 95%CI 1.01 - 3.41; p = 0.045). When evaluated by NUTRIC, nutritional risk was associated with renal replacement therapy (OR = 2.10; 95%CI 1.02 - 4.15; p = 0.040) and death (OR = 3.48; 95%CI 1.88 - 6.44; p < 0.001).
In critically ill patients, high nutritional risk was positively associated with an increased risk of clinical outcomes including hospital death.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):333-339
DOI 10.5935/0103-507X.20190045
To describe the use of noninvasive ventilation to prevent tracheal intubation in children in a pediatric intensive care unit and to analyze the factors related to respiratory failure.
A retrospective cohort study was performed from January 2016 to May 2018. The study population included children aged 1 to 14 years who were subjected to noninvasive ventilation as the first therapeutic choice for acute respiratory failure. Biological, clinical and managerial data were analyzed by applying a model with the variables that obtained significance ≤ 0.20 in a bivariate analysis. Logistic regression was performed using the ENTER method. The level of significance was set at 5%.
The children had a mean age of 68.7 ± 42.3 months, 96.6% had respiratory disease as a primary diagnosis, and 15.8% had comorbidities. Of the 209 patients, noninvasive ventilation was the first option for ventilatory support in 86.6% of the patients, and the fraction of inspired oxygen was ≥ 0.40 in 47% of the cases. The lethality rate was 1.4%. The data for the use of noninvasive ventilation showed a high success rate of 95.3% (84.32 - 106). The Pediatric Risk of Mortality (PRISM) score and the length of stay in the intensive care unit were the significant clinical variables for the success or failure of noninvasive ventilation.
A high rate of effectiveness was found for the use of noninvasive ventilation for acute episodes of respiratory failure. A higher PRISM score on admission, comorbidities associated with respiratory symptoms and oxygen use ≥ 40% were independent factors related to noninvasive ventilation failure.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):333-339
DOI 10.5935/0103-507X.20190045
To describe the use of noninvasive ventilation to prevent tracheal intubation in children in a pediatric intensive care unit and to analyze the factors related to respiratory failure.
A retrospective cohort study was performed from January 2016 to May 2018. The study population included children aged 1 to 14 years who were subjected to noninvasive ventilation as the first therapeutic choice for acute respiratory failure. Biological, clinical and managerial data were analyzed by applying a model with the variables that obtained significance ≤ 0.20 in a bivariate analysis. Logistic regression was performed using the ENTER method. The level of significance was set at 5%.
The children had a mean age of 68.7 ± 42.3 months, 96.6% had respiratory disease as a primary diagnosis, and 15.8% had comorbidities. Of the 209 patients, noninvasive ventilation was the first option for ventilatory support in 86.6% of the patients, and the fraction of inspired oxygen was ≥ 0.40 in 47% of the cases. The lethality rate was 1.4%. The data for the use of noninvasive ventilation showed a high success rate of 95.3% (84.32 - 106). The Pediatric Risk of Mortality (PRISM) score and the length of stay in the intensive care unit were the significant clinical variables for the success or failure of noninvasive ventilation.
A high rate of effectiveness was found for the use of noninvasive ventilation for acute episodes of respiratory failure. A higher PRISM score on admission, comorbidities associated with respiratory symptoms and oxygen use ≥ 40% were independent factors related to noninvasive ventilation failure.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):340-346
DOI 10.5935/0103-507X.20190049
To identify the underlying factors that affect fluid resuscitation in septic patients.
The present study was a case-control study of 181 consecutive patients admitted to a Medical Intensive Care Unit between 2012 and 2016 with a diagnosis of sepsis. Demographic, clinical, radiological and laboratory data were analyzed.
One hundred-thirty patients (72%) received ≥ 30mL/kg of IV fluids on admission. On univariate analyses, a past history of coronary artery disease and heart failure was associated with less fluid therapy. On multivariate analyses, a history of heart failure (OR = 2.31; 95%CI 1.04 - 5.14) remained significantly associated with receiving less IV fluids. Left ventricular ejection fraction, systolic/diastolic function, left ventricular hypertrophy and pulmonary hypertension were not associated with IV fluids. The amount of IV fluids was not associated with differences in mortality. During the first 24 hours, patients with a past history of heart failure received 2,900mLof IV fluids [1,688 - 4,714mL] versus 3,977mL [2,500 - 6,200mL] received by those without a history of heart failure, p = 0.02.
Septic patients with a past history of heart failure received 1L less IV fluids in the first 24 hours with no difference in mortality.
Abstract
Rev Bras Ter Intensiva. 2019;31(3):340-346
DOI 10.5935/0103-507X.20190049
To identify the underlying factors that affect fluid resuscitation in septic patients.
The present study was a case-control study of 181 consecutive patients admitted to a Medical Intensive Care Unit between 2012 and 2016 with a diagnosis of sepsis. Demographic, clinical, radiological and laboratory data were analyzed.
One hundred-thirty patients (72%) received ≥ 30mL/kg of IV fluids on admission. On univariate analyses, a past history of coronary artery disease and heart failure was associated with less fluid therapy. On multivariate analyses, a history of heart failure (OR = 2.31; 95%CI 1.04 - 5.14) remained significantly associated with receiving less IV fluids. Left ventricular ejection fraction, systolic/diastolic function, left ventricular hypertrophy and pulmonary hypertension were not associated with IV fluids. The amount of IV fluids was not associated with differences in mortality. During the first 24 hours, patients with a past history of heart failure received 2,900mLof IV fluids [1,688 - 4,714mL] versus 3,977mL [2,500 - 6,200mL] received by those without a history of heart failure, p = 0.02.
Septic patients with a past history of heart failure received 1L less IV fluids in the first 24 hours with no difference in mortality.
