RESUMEN
Objective:To determine the risk factors of extubation failure and its effect on the prognosis of patients who had successfully passed a spontaneous breathing trial (SBT).Methods:The clinical data of patients with mechanical ventilation more than 24 hours who passed SBT admitted to department of intensive care unit (ICU) of First Hospital of Qinhuangdao from November 2018 to November 2019 were retrospectively analyzed. According to the outcome of weaning within 48 hours after weaning, patients were divided into weaning success group and weaning failure group. The baseline data, the presence of basic cardiopulmonary diseases, B-type natriuretic peptide (BNP), fluid balance, albumin and hemoglobin within 24 hours before weaning, the time of mechanical ventilation before weaning, rapid shallow breathing index (RSBI) during SBT, oxygenation index, cough peak flow at the end of SBT, and prognostic indicators were collected. The outcome of weaning was taken as the dependent variable, and the observation factors were taken as the independent variable for univariate analysis. The factors with statistical significance in univariate analysis were analyzed by binary Logistic regression to determine the influencing factors of weaning failure.Results:Of the 204 patients, 167 (81.9%) were successfully weaned, and 37 (18.1%) failed. Compared with the weaning success group, the total duration of mechanical ventilation and the length of ICU stay in the weaning failure group were significantly longer [days: 13.0 (7.5, 23.5) vs. 5.0 (3.0, 8.0), 17.0 (12.5, 31.0) vs. 10.0 (6.0, 15.0), both P < 0.01], and the tracheotomy rate and mortality were significantly higher (32.4% vs. 0%, 51.4% vs. 0%, both P < 0.01). Univariate analysis showed that there were significant differences in age, proportion of patients with cardiopulmonary diseases, BNP and cough peak flow between weaning failure group and weaning success group [age (years old): 70.65±15.78 vs. 62.69±15.82, cardiopulmonary diseases: 62.2% vs. 24.6%, BNP (ng/L): 416.87 (32.70, 1 225.80) vs. 45.36 (10.00, 273.60), cough peak flow (L/min): 59.89±9.06 vs. 83.84±16.52, all P < 0.01]. However, there were no significant differences in gender, acute physiology and chronic health evaluationⅡ (APACHEⅡ) at admission, mechanical ventilation time before weaning, albumin, hemoglobin, oxygenation index, RSBI and fluid balance 24 hours before weaning between weaning failure group and weaning success group [male: 51.4% vs. 68.3%, APACHEⅡ: 16.70±6.65 vs. 15.67±6.28, mechanical ventilation time before weaning (days): 6.0 (2.5, 11.0) vs. 5.0 (3.0, 8.0), albumin (g/L): 27.78±4.15 vs. 27.76±4.46, hemoglobin (g/L): 102.43±15.80 vs. 100.61±17.19, oxygenation index (mmHg, 1 mmHg = 0.133 kPa): 359.33±79.83 vs. 365.75±78.23, RSBI (times·L -1·min -1): 50.73±24.97 vs. 46.76±15.53, positive fluid balance: 70.3% vs. 69.5%, all P > 0.05]. The results of binary Logistic regression analysis showed that age ≥ 75 years old [odds ratio ( OR) = 3.099, 95% confidence interval (95% CI) was 1.003-9.574, P = 0.049], presence of cardiopulmonary diseases ( OR = 3.599, 95% CI was 1.126-11.498, P = 0.031), BNP within 24 hours before weaning ( OR = 1.002, 95% CI was 1.000-1.003, P = 0.005) were the risk factors of extubation failure, while cough peak flow at the end of SBT was the protective factor ( OR = 0.869, 95% CI was 0.823-0.917, P = 0.000). Conclusions:For patients who had successfully passed SBT, age ≥ 75 years old, the presence of cardiopulmonary diseases and an increased level of BNP within 24 hours were the risk factors of extubation failure. In addition, the higher the cough peak flow at the end of SBT, the lower the risk of weaning failure will be.
RESUMEN
Resumen La ventilación mecánica prolongada incrementa el riesgo de complicaciones; asimismo, el retiro temprano de la misma expone al paciente a los riesgos que tenía antes de iniciarla. Cuando hablamos de ventilación mecánica prolongada y retiro temprano, el equilibrio sigue siendo controvertido, además de ser un tema no resuelto, más aun al referirnos al paciente neurológico. La protección de la vía aérea y evitar mayor afectación de la distensibilidad cerebral son los propósitos de la ventilación mecánica invasiva en el paciente con deterioro neurológico, además de acoplar al paciente con el ventilador, en particular ante patrones respiratorios anormales. De los pacientes que requieren ventilación mecánica en la unidad de cuidados intensivos, alrededor de 20% corresponde a padecimientos neurológicos. El momento apropiado para la extubación puede estar basado en una decisión clínica, que puede considerarse subjetiva; por esta razón, se han propuesto parámetros objetivos para tomar esta decisión, éstos permitirán identificar a los pacientes aptos para realizar prueba de ventilación espontánea con gran posibilidad de éxito. La búsqueda de un parámetro que evalúe el éxito o fracaso de la extubación en el paciente neurológico es un problema no resuelto hasta el momento, por lo que deberá ser tema de más estudios; hasta el día de hoy la Escala de Coma de Glasgow (EC) es la variable asociada con buenos o malos resultados.
Abstract Long mechanical ventilation (MV) increases the risk of complications; moreover, early retirement of it exposes the patient to the risks presented before starting. The balance in speaking of prolonged mechanical ventilation and early retirement remains controversial, besides being an unresolved issue, even more so when speaking of neurological patients. Protection of the airway and prevention of further compromised brain compliance are the purposes of initiating invasive mechanical ventilation in patients with neurological impairment in addition to engaging the patient with particular fan under the presence of abnormal breathing patterns. Of patients requiring mechanical ventilation in the Intensive Care Unit (ICU), about 20% are due to neurological diseases. The appropriate time for extubation may be based on a clinical decision, which may be considered subjective, for this reason objective parameters have been proposed to make such a decision, they will identify candidates to perform test of spontaneous ventilation with great chance of success. The search for a parameter to evaluate the success or failure of extubation in neurological patient is a problem not solved so far, so it should be the subject of further studies, until today the Glasgow Coma Scale (SCG) is the variable associated with good or bad results.