Utilization of a Risk Stratification Tool and Volume-Based Cuff Leak Test to Assess Postextubation Stridor.

BACKGROUND: Postextubation stridor (PES) is an imminently life-threatening event. Maximizing patient safety requires a systematic approach to screen patients for PES risk factors and a standardized test to evaluate that risk. This retrospective study of adult subjects was based on quality assurance data including standardized surveillance screening criteria and a volume-based cuff leak test (CLT) to evaluate PES risk among predominantly surgical-trauma and neurotrauma subjects. Data characterizing PES subjects also were collected. METHODS: Data were collected between May 2010-December 2017 for all intubated subjects in our surgical-trauma, neurotrauma, and medical ICUs. Respiratory therapists were trained in performing both PES risk assessment surveillance and a volume-based CLT. A pre hoc cutoff leak volume of < 110 mL defined a true positive test result when associated with PES, and a leak ≥ 110 mL defined a true negative test if PES was absent. Multiple comparisons were analyzed by Kruskal-Wallis tests and dichotomous variables assessed by Fisher exact tests. Alpha was set at 0.05. RESULTS: In 681 pre-extubation CLTs ∼85% produced true-negative results and 15% consisted of true-positive (∼4%), false-negative (∼5%), and false-positive (∼6%) results. Positive and negative predictive values were 0.42 (0.32-0.54) and 0.94 (0.92-0.96), respectively. The PES likelihood ratio was 7.0, and correct classification was 89%. Of the 115 PES incidences occurring in 112 PES cases, 67% were female and 48% had suffered acute brain injury. CONCLUSIONS: Among predominantly surgical-trauma and neurotrauma subjects with a CLT, leak volume of ≥ 110 mL was associated with a PES risk of ∼6%, whereas the risk of PES was 7 times greater when the leak volume was < 110 mL.

Gargle test for successful extubation in critically ill patients underwent head and neck surgeries: A new test.

Background: Improvement of predictive tools for recognition of airway edema is crucial for safe extubation and patient safety. This study aimed to evaluate the diagnostic accuracy of the Gargle test (GT) as a new test for assessing airway edema and predicting successful extubation in patients admitted to the intensive care unit (ICU). Method: In this prospective observational study, patients underwent head and neck surgeries and admitted to ICU included. All the patients were weaned based on the same protocol.Quantitative Cuff Leak Test (CLT) and qualitative CLTwere first applied followed by GT with normal saline 0.9%. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated. Results: One hundred and eighteen (male 67, female 51) participated in this study. The agreement between GT and CLT was low (Kappa: quantitative CLT 0.07, qualitative CLT 0.21). The GT compared to CLT had higher sensitivity (33.3% vs 16.6%), specificity (96.3% vs qualitative CLT 92.8%, quantitative CLT 79.4%), PPV (33.3% vs qualitative CLT 11.11%, quantitative CLT 4.0%), NPV (96.3% vs qualitative CLT 95.4%, quantitative CLT 94.6%), and accuracy (92.92% vs qualitative CLT 88.98%, quantitative CLT 76.27%. The cut-off value for GT was estimated 16.5% (sensitivity 74.1% and specificity 60%). Conclusion: The GT is a simple accurate test and can be used as a new test in the ICU for recognition of airway edema and prediction of safe extubation in patients with head and neck surgeries.

A novel technique for assessment of post-extubation airway obstruction can successfully replace the conventional cuff leak test: a pilot study.

BACKGROUND: Post-extubation airway obstruction is an important complication of tracheal intubation. The cuff leak test is traditionally used to estimate the risk of this complication. However, the cuff leak test parameters are not constant and may depend on the respiratory system and ventilator settings. Furthermore, deflating the cuff also be a risk factor for patient-ventilator asynchrony and ventilator-associated pneumonia. Instead of using the cuff leak test, we measured the pressure of the leak to the upper airway through the gap between the tube and glottis with a constant low flow from the lumen above the cuff without deflating the cuff and called it "pressure above the cuff." The purpose of this study was to investigate whether pressure above the cuff can be used as an alternative to the cuff leak volume. METHODS: This prospective observational study was conducted at Kumamoto University Hospital after obtaining approval from the institutional review board. The pressure above the cuff was measured using an endotracheal tube with an evacuation lumen above the cuff and an automated cuff pressure modulation device. We pumped 0.16 L per minute of air and measured the steady-state pressure using an automated cuff pressure modulation device. Then, the cuff leak test was performed, and the cuff leak volume was recorded. The cuff leak volume was defined as the difference between the expiratory tidal volume with the cuff inflated and deflated. The relationship between the pressure above the cuff and cuff leak volume was evaluated. The patient-ventilator asynchrony during each measurement was also examined. RESULTS: The pressure above the cuff was measured, and the cuff leak volume was assessed 27 times. The pressure above the cuff was significantly correlated with the cuff leak volume (r = -0.76, p < 0.001). Patient-ventilator asynchrony was detected in 37% of measurements during the cuff leak test, but not during the pressure above the cuff test. CONCLUSIONS: This study suggests that pressure above the cuff measurement may be a less complicated alternative to the conventional cuff leak test for evaluation of the risk of post-extubation airway obstruction. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry (UMIN000039987; March 30, 2020). https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000044604.

The Effects of Combining Two Postures and Two Ventilator Flow Waveforms on the Cuff Leak Test.

BACKGROUND: The cuff leak test (CLT) has been shown to have excellent specificity and moderate sensitivity for predicting postextubation stridor (PES). However, the ventilator flow waveform and the subject position are not uniform in current clinical practice. METHODS: We conducted a prospective cohort study in the respiratory ICU of the Beijing Chaoyang Hospital, Capital Medical University. Prior to extubation, 4 CLTs, combining 2 different postures and ventilator flow waveforms, were conducted, and the diagnostic performance of each test was assessed. RESULTS: Of the 143 included subjects, PES occurred in 13 (9.1%), and 10 (7%) subjects required re-intubation. Initially, an air leak volume of 110 mL was used as the standard to judge performance. The test that involved the square waveform and the subject in semi-recumbent position (test 4) had the best diagnostic performance, with a specificity of 80% and a sensitivity of 67% for predicting PES. After analyzing the receiver operating characteristic curve, an optimal diagnostic threshold of 116 mL for air leak volume was found to result in a specificity of 92% and a sensitivity of 63% for test 4. Additionally, when the air leak ratio of test 4 was 0.32, the area under the curve was 0.76, the specificity was 92%, and the sensitivity was 62%. CONCLUSIONS: In this study, performing the CLT with the subject in semi-recumbent position using the square waveform appeared to allow for the best prediction of PES.

Cuff Leak Test and Airway Obstruction in Mechanically Ventilated Intensive Care Unit Patients: A Pilot Randomized Controlled Clinical Trial.

Rationale: Laryngeal edema is a known complication of endotracheal intubation that may cause airway obstruction upon extubation. The only test available to predict this complication is the cuff leak test (CLT). Objectives: Given the uncertainty of the CLT's clinical utility, we conducted the COMIC (Cuff Leak Test and Airway Obstruction in Mechanically Ventilated ICU Patients) pilot study to examine the feasibility of undertaking a larger trial. Methods: COMIC is a multicentered, parallel-group randomized trial performed in Canada, Saudi Arabia, and Poland. We enrolled mechanically ventilated adults admitted to the intensive care unit who were deemed ready for extubation. Those allocated to the intervention arm had the results of their CLT communicated to the healthcare team, who then decided to proceed with extubation or not. In those randomized to the control arm, the CLT results were not communicated to the healthcare team and patients were extubated, regardless of the CLT result. The primary outcomes focused on feasibility. Results: One hundred patients (56 in the intervention and 44 in the control arm) were enrolled. All feasibility criteria were met, including 1) recruitment rate of 7.6 patients/month, 2) consent rate of 88.3% (95% confidence interval [CI], 82.1-94.5%), and 3) protocol adherence of 98% (95% CI, 95-100%). There were two episodes of clinically significant stridor in the intervention group and four patients who required reintubation in each group. Conclusions: The results of the COMIC pilot trial support the feasibility of a larger trial to determine the effect of the CLT on reintubation and clinically important stridor.Clinical trial registered with www.clinicaltrials.gov (NCT03372707).

Frequency of Positive Cuff Leak Test Before Extubation in Robotic Surgeries Done in Steep Trendelenburg Position.

Anaesthesia for robotic surgeries done in steep trendelenburg position are associated with risks such as facial oedema, conjunctival chemosis, raised intraocular pressure, laryngeal oedema, and delayed awakening. We proposed the use of the cuff leak test in them to record the frequency of laryngeal oedema at the end of surgery and attempted to find its correlation with probable risk factors. We conducted a prospective observational study of 100 patients aiming primarily to assess the frequency of positive cuff leak test in robotic abdominal surgeries performed in trendelenburg position. The secondary outcomes were to check its correlation with intravenous fluid administration, duration of pneumoperitoneum, and angle of trendelenburg position. We also recorded the frequency of chemosis, the frequency of post-extubation stridor in 24 h post-operatively, and the frequency of reintubation. Out of 100 participants undergoing elective abdominal robotic surgery in trendelenburg position, ninety were analysed. Total 31.6% (n = 30) participants showed positive cuff leak test. Chemosis was observed in 31 (32.6%) participants. No patient experienced post-extubation stridor or required reintubation during post-operative follow up. There was a no correlation between cuff leak test and intravenous fluid, duration of pneumo-peritoneum, or with angle of trendelenburg. The frequency of positive cuff leak test was high in patients at the end of robotic surgery but none of these patients had post-extubation stridor or required reintubations. There was no correlation with the fluid, angle, or duration of surgery. Clinical Trials Registry of India (CTRI/2017/04/008289), ctri.nic.in.

Performance of the cuff leak test in adults in predicting post-extubation airway complications: a systematic review and meta-analysis.

BACKGROUND: Clinical practice guidelines recommend performing a cuff leak test in mechanically ventilated adults who meet extubation criteria to screen those at high risk for post-extubation stridor. Previous systematic reviews demonstrated excellent specificity of the cuff leak test but disagreed with respect to sensitivity. We conducted a systematic review and meta-analysis to assess the diagnostic accuracy of the cuff leak test for predicting post-extubation airway complications in intubated adult patients in critical care settings. METHODS: We searched Medline, EMBASE, Scopus, ISI Web of Science, the Cochrane Library for eligible studies from inception to March 16, 2020, without language restrictions. We included studies that examined the diagnostic accuracy of cuff leak test if post-extubation airway obstruction after extubation or reintubation was explicitly reported as the reference standard. Two authors in duplicate and independently assessed the risk of bias using the Quality Assessment for Diagnostic Accuracy Studies-2 tool. We pooled sensitivities and specificities using generalized linear mixed model approach to bivariate random-effects meta-analysis. Our primary outcomes were post-extubation airway obstruction and reintubation. RESULTS: We included 28 studies involving 4493 extubations. Three studies were at low risk for all QUADAS-2 risk of bias domains. The pooled sensitivity and specificity of cuff leak test for post-extubation airway obstruction were 0.62 (95% CI 0.49-0.73; I2 = 81.6%) and 0.87 (95% CI 0.82-0.90; I2 = 97.8%), respectively. The pooled sensitivity and specificity of the cuff leak test for reintubation were 0.66 (95% CI 0.46-0.81; I2 = 48.9%) and 0.88 (95% CI 0.83-0.92; I2 = 87.4%), respectively. Subgroup analyses suggested that the type of cuff leak test and length of intubation might be the cause of statistical heterogeneity of sensitivity and specificity, respectively, for post-extubation airway obstruction. CONCLUSIONS: The cuff leak test has excellent specificity but moderate sensitivity for post-extubation airway obstruction. The high specificity suggests that clinicians should consider intervening in patients with a positive test, but the low sensitivity suggests that patients still need to be closely monitored post-extubation.

Utilidad de la prueba de fuga peritubo para la seguridad de la extubación / Usefulness of the test of leak around the tube for patient safety

Introducción: La prueba de fuga de aire peritubo no es invasiva. Es relativamente fácil de realizar y proporciona una indicación de la permeabilidad de la vía respiratoria superior. Objetivo: Evaluar la eficacia de la prueba de fuga peritubo, medidas de modo cualitativas y cuantitativa, para la seguridad de la extubación. Método: Se realizó un estudio descriptivo, prospectivo de corte transversal de los pacientes de cualquier género, programados para intervención quirúrgica por: microcirugía laríngea, cirugía para bocio endotoraxico, cirugía maxilofacial y aquellos con antecedentes de intubación difícil que requirieron más de tres intentos de intubación y/o uso de conductores o guías. La muestra estuvo conformada por 52 pacientes que cumplieron los criterios de selección. El análisis estadístico se realizó mediante el cálculo de medidas para variables cualitativas y para las cuantitativas el Chi-cuadrado de Pearson (x2). Resultados: El grupo con mayor frecuencia fueron los menores de 40 años. Predominó el sexo masculino. El tubo 7,5 fue el más utilizado (50 por ciento). Los resultados de la concordancia entre la prueba cualitativa y cuantitativa según presencia o no de fuga de aire peritubo fue de 90,4 por ciento respectivamente. Las complicaciones según pruebas fueron escasas. Conclusiones: Ambas pruebas constituyen herramientas útiles para el diagnóstico de obstrucción de la vía respiratoria durante la extubación. La modalidad cualitativa resultó ser tan eficaz como la cuantitativa y más fácil de reproducir para los operadores en el estudio(AU)

Introduction: The air leak test around the endotracheal tube is not invasive. It is relatively easy to perform and provides an indication of the permeability of the upper airway. Objective: To evaluate the effectiveness of the air leak" test around the endotracheal tube, qualitatively and quantitatively measured, for the safety of extubation. Method: A descriptive, prospective and cross-sectional study was carried out with patients of any gender scheduled for surgical intervention by laryngeal microsurgery, surgery for endotoxic goiter, maxillofacial surgery, and those with a history of difficult intubation that required more than three attempts at intubation and/or the usage of drivers or guides. The sample consisted of 52 patients who met the selection criteria. Statistical analysis was performed by calculating measures for qualitative variables, while for quantitative variables, Pearson's chi-square (x2) was used. Results: The group with more frequency was represented by those under 40 years. The male sex prevailed. The 7.5 tube was the most used (50 percent). The results of the concordance between the qualitative and quantitative test according to the presence or absence of air leak around the tube was 90.4 percent, respectively. Complications based on the tests were scarce. Conclusions: Both tests are useful tools for the diagnosis of airway obstruction during extubation. The qualitative modality proved to be as effective as the quantitative and easier to reproduce for the operators in the study(AU)

Effect of Two Regimens of Fluid Administration on Airway Edema in Prone-Position Surgery.

BACKGROUND: Surgeries in prone position expose a patient to multitude of complications including laryngeal edema which may be related to the volume of fluid administered. Administering larger volumes of fluid intraoperatively may contribute to significant tissue edema, leading many anesthesiologists to practice a restrictive fluid infusion strategy. Although previous studies have compared fluid infusion strategies, changes in airway dimensions leading to airway edema have not been extensively investigated. Here, we compared two fluid infusion regimens in patients undergoing spine surgery in the prone position, and assessed their association with airway edema by means of the cuff leak test (CLT). AIMS: The aim of this study was to test the hypothesis whether a larger volume of crystalloid administration in spine surgeries performed in prone position would result in greater chances of airway edema, than would a restricted infusion policy, utilizing the CLT. MATERIALS AND METHODS: After ethical committee approval, thirty patients, aged 21-60 years, American Society of Anesthesiologists Status I or II, scheduled for elective spine surgery in the prone position, were selected. Group 1 (restrictive group) received 3 mL.kg - 1.h - 1, whereas Group 2 (permissive group) received 5 mL.kg - 1.h - 1 of crystalloids plus urine output replacement. The airway edema was assessed by CLT which was performed soon after intubation (T1) and before extubation (T2). Cuff leak volume (CLV) was calculated from the difference in tidal volumes before (VT i) and after cuff deflation (VT e). Airway edema was evaluated by calculating the differences in the CLV at T1 and T2 (ΔCLV); the more the value of Δ CLV which means greater difference between these two points, the more the decrease in laryngeal lumen, signifying an increased risk of airway edema. RESULTS: Decrease in laryngeal lumen was observed in patients who received permissive fluid regimen than that of the restrictive group, signifying more chances of airway edema in the former group. In addition, a poor correlation was found between the duration of anesthesia and development of airway edema in our study group. CONCLUSIONS: Because surgeries in the prone position are at risk of airway edema, restrictive fluid regimen strategy should be preferred over the liberal one as there are more chances of reduction in laryngeal lumen dimensions with permissive fluid infusions.

Perioperative complications with multilevel anterior and posterior cervical decompression and fusion.

OBJECTIVE: Cervical spondylotic myelopathy (CSM) is a progressive degenerative pathology that frequently affects older individuals and causes spinal cord compression with symptoms of neck pain, radiculopathy, and weakness. Anterior decompression and fusion is the primary intervention to prevent neurological deterioration; however, in severe cases, circumferential decompression and fusion is necessary. Published data regarding perioperative morbidity associated with these complex operations are scarce. In this study, the authors sought to add to this important body of literature by documenting a large single-surgeon experience of single-session circumferential cervical decompression and fusion. METHODS: A retrospective analysis was performed to identify intended single-stage anterior-posterior or posterior-anterior-posterior cervical spine decompression and fusion surgeries performed by the primary surgeon (V.C.T.) at Rush University Medical Center between 2009 and 2016. Cases in which true anterior-posterior cervical decompression and fusion was not performed (i.e., those involving anterior-only, posterior-only, or delayed circumferential fusion) were excluded from analysis. Data including standard patient demographic information, comorbidities, previous surgeries, and intraoperative course, along with postoperative outcomes and complications, were collected and analyzed. Perioperative morbidity was recorded during the 90 days following surgery. RESULTS: Seventy-two patients (29 male and 43 female, mean age 57.6 years) were included in the study. Fourteen patients (19.4%) were active smokers, and 56.9% had hypertension, the most common comorbidity. The most common clinical presentation was neck pain in 57 patients (79.2%). Twenty-three patients (31.9%) had myelopathy, and 32 patients (44.4%) had undergone prior cervical spine surgery. Average blood loss was 613 ml. Injury to the vertebral artery was encountered in 1 patient (1.4%). Recurrent laryngeal nerve palsy was observed in 2 patients (2.8%). Two patients (2.8%) had transient unilateral hand grip weakness. There were no permanent neurological deficits. Dysphagia was encountered in 45 patients (62.5%) postoperatively, with 23 (32%) requiring nasogastric parenteral nutrition and 9 (12.5%) patients ultimately undergoing percutaneous endoscopic gastrostomy (PEG) placement. Nine of the 72 patients required a tracheostomy. The incidence of pneumonia was 6.9% (5 patients) overall, and 2 of these patients were in the tracheostomy group. Superficial wound infections occurred in 4 patients (5.6%). Perioperative death occurred in 1 patient. Reoperation was necessary in 10 patients (13.9%). Major perioperative complications (permanent neurological deficit, vascular injury, tracheostomy, PEG tube, stroke, or death) occurred in 30.6% of patients. The risk of minor perioperative complications (temporary deficit, dysphagia, deep vein thrombosis, pulmonary embolism, urinary tract infection, pneumonia, or wound infection) was 80.6%. CONCLUSIONS: Single-session anterior-posterior cervical decompression and fusion is an inherently morbid operation required in select patients with cervical spondylotic myelopathy. In this large single-surgeon series, there was a major perioperative complication risk of 30.6% and minor perioperative complication risk of 80.6%. This overall elevated risk for postoperative complications must be carefully considered and discussed with the patient preoperatively. In some situations, shared decision making may lead to the conclusion that a procedure of lesser magnitude may be more appropriate.

Cuff Leak Test and Airway Obstruction in Mechanically Ventilated ICU Patients (COMIC): a pilot randomised controlled trial protocol.

INTRODUCTION: Endotracheal intubation and invasive mechanical ventilation are lifesaving interventions that are commonly performed in the intensive care unit (ICU). Laryngeal oedema is a known complication of intubation that may cause airway obstruction in a patient on extubation. To date, the only test available to predict this complication is the cuff leak test (CLT); however, its diagnostic accuracy and utility remains uncertain. Herein, we report the protocol for the CuffLeak and AirwayObstruction in MechanicallyVentilated ICU Patients (COMIC) pilottrial. METHODS AND ANALYSIS: This will be a multicentred, pragmatic, pilot randomised controlled trial (RCT). We will enrol 100 mechanically ventilated patients in the ICU who are deemed ready for extubation. We will exclude patients at a high risk of laryngeal oedema. All enrolled patients will have a CLT done before extubation. In the intervention arm, the results of the CLT will be communicated to the bedside physician, and decision to extubate will be left to the treating team. In the control arm, respiratory therapist will not communicate the results of the CLT to the treating physician, and the patient will be extubated regardless of the CLT result. Randomisation will be done in a 1:1 allocation ratio, stratified by size of the endotracheal tube and duration of invasive mechanical ventilation.Although we will examine all clinical outcomes relevant for the future COMIC RCT, the primary outcomes of the COMIC pilottrial will be feasibility outcomes including: consent rate, recruitment rate and protocol adherence. Clinical outcomes include postextubation stridor, reintubation, emergency surgical airway, ICU mortality, in hospital mortality, duration of mechanical ventilation and ICU length of stay in days. ETHICS AND DISSEMINATION: The Hamilton Integrated Research Ethics Board, Imam Abdulrahman Bin Faisal University Institutional Review Board and Bioethical Commission of the Jagiellonian University approved this study. The trial results will be disseminated via publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03372707.

Cuff Leak Test for the Diagnosis of Post-Extubation Stridor: A Multicenter Evaluation Study.

BACKGROUND:: Cuff leak test was developed to predict the occurrence of post-extubation stridor (PES). This study evaluated the diagnostic performance of this test in unselected critically ill patients. METHODS:: Multicenter prospective study including unselected ventilated patients at the time of their first planned extubation. The diagnostic performance of 4 different cuff leak tests was assessed. RESULTS:: Post-extubation stridor occurred in 34 (9.4%) of 362 included patients. Compared to patients without PES, patients with PES required more frequently reintubation (6 [17.6%] vs 26 [7.9%], P = .041), prolonged duration of ventilation (6 [3-13] vs 5 [2-9] days, P = .029), and longer intensive care unit (ICU) stay (12 [6-17.5] vs 7.5 [4-13] days, P = .018). However, ICU mortality was similar in both groups (1 [2.9%] vs 23 [7.0%], P = .61). The 4 cuff leak tests display poor diagnostic accuracy: sensitivities ranging from 27% to 46%, specificities from 70% to 88%, positive predictive values from 14% to 19%, and negative predictive values from 92% to 93%. CONCLUSION:: Post-extubation stridor occurs in less than 10% of unselected critically ill patients. The several cuff leak tests display limited diagnostic performance for the detection of PES. Given the high rate of false positives, routine cuff leak test may expose to undue prolonged mechanical ventilation.

Application of CLT guiding offline extubation in patient with tracheal intubation of mechanical ventilation / 中国医学装备

Objective: To explore the application of the cuff-leak test(CLT)guiding offline extubation in patients with tracheal intubation of mechanical ventilation.Methods: 64 patients with tracheal intubation who underwent mechanical ventilation were divided into CLT-negative group(47 cases)and CLT-positive group(17 cases)according to leakage situation of CLT.The CLT guiding offline extubation were adopted in the study and some basic situations,such as body mass index(BMI),APACHE-Ⅱ and so on,of the two groups were compared.And the relative situation of intubation,blood gas analysis index,vital signs,the occurrence rate of upper airway obstruction(UAO)post removing intubation and re-intubation rate between the two groups also were compared,and then the risk factors of influencing UAO were further analyzed.Results: The BMI of CLT-negative group was significantly smaller than that of CLT-positive group(t=2.44,P＜0.05).The occurrence rate of UAO and re-intubation rate of CLT-negative group(6.38％and 2.13％)were significantly lower than that of CLT-positive group(35.29％and 17.65％)(x2=8.63,x2=5.13,P＜0.05),respectively.The differences of BMI,APACHE-Ⅱ scores,intubation time,air sac pressure,PaO2and SpO2between patients with UAO and patients without UAO were significant(t=5.63,t=2.65,t=4.27,t=3.35,t=2.37,t=2.66,P＜0.05).The results of Logistic regression analysis showed that the BMI,APACHEⅡ score,intubation time,air sac pressure were independent risk factors for occurring UAO post extubation.Conclusion: The CLT guiding offline extubation in patient with tracheal intubation of mechanical ventilation can effectively reduce the re-intubation rate.For these patients with obesity,high APACHE-Ⅱ score,long intubation time and big air sac pressure,the risk of occurring UAO is higher.Therefore,the number of intubation pre extubation should be reduced for them,and their physiological status should be comprehensively assessed so as to decrease the occurrence rate of UAO.

Extubación fallida en una unidad de cuidados intensivos de la Ciudad de México / Failed extubation in an intensive care unit of Mexico City

Resumen: ANTECEDENTES: el soporte ventilatorio invasivo es una medida terapéutica de uso común en las unidades de cuidados intensivos; una vez aliviada la enfermedad que ocasionó el apoyo ventilatorio se inicia con el retiro de esta modalidad. Cuando se realiza el retiro puede ocurrir una extubación fallida incluso en 20% de los pacientes, requiriendo reintubación. OBJETIVO: reportar la frecuencia de extubación fallida en la Unidad de Cuidados Intensivos Adultos del Hospital 1° de Octubre del ISSSTE. MATERIAL Y MÉTODO: estudio analítico, observacio4nal y transversal, realizado en la Unidad de Cuidados Intensivos, en el que se analizaron expedientes en el periodo del 1 de marzo de 2014 al 28 de febrero de 2015, con apoyo de ventilación mecánica invasiva por más de 24 horas y que se extubaron después de una prueba de ventilación espontánea exitosa. RESULTADOS: se incluyeron 146 expedientes, 74 (51%) fueron de pacientes del sexo femenino, con promedio de edad de 56 años. Las indicaciones de la ventilación mecánica fueron: estado de choque, n=44 (30%), posquirúrgicos, n=40 (27%). El porcentaje de falla del retiro de la ventilación fue de 18%. El riesgo de prevalencia de extubación fallida fue: midazolam OR 4.8 (IC95% 1.56-14.8, p=0.002), obesidad OR 2.5 (IC95% 1.07-6.16), deterioro neurológico como indicación de ventilación OR 6 (IC95% 3.14-11.8), acidosis metabólica OR 5.2 (IC95% 1.2-22.6). CONCLUSIONES: la prevalencia de extubación fallida en nuestra unidad de cuidados intensivos es de 18%, similar a lo reportado en la bibliografía.

Abstract: BACKGROUND: Invasive ventilatory support is a therapeutic measure commonly used in the Intensive Care Units, cured the disease that caused the ventilatory support begins with withdrawal of this modality. Once the withdrawal is performed, a failed extubation can occur in up to 20% of patients, requiring reintubation. OBJECTIVE: To report the frequency of failed extubation in the Adult Intensive Care Unit from the Hospital 1° de Octubre, ISSSTE, Mexico. MATERIAL AND METHOD: An analytical, observational and transversal study was made in the intensive care unit; files were analyzed in the period from March 1st, 2014 to February 28, 2015, with support of mechanical ventilation for more than 24 hours and extubated after a successful spontaneous breath trail. RESULTS: One hundred forty-six records were identified, 74 (51%) were female, with a mean age of 56 years. The indications for mechanical ventilation were: shock state 44 (30%), postoperative 40 (27%). The percentage of ventilation withdrawal failure was 18%. The risk of prevalence for failed extubation: for midazolam OR 4.8 (95% CI 1.56-14.8, p=0.002), obesity OR 2.5 (95% CI 1.07-6.16), neurological deterioration as an indication of ventilation OR 6 (95% CI 3.14-11.8), metabolic acidosis OR 5.2 (95% CI 1.2-22.6). CONCLUSIONS: The prevalence of failed extubation in our intensive care unit is 18%, similar to that reported in the literature.

Prophylactic Corticosteroids for Prevention of Postextubation Stridor and Reintubation in Adults: A Systematic Review and Meta-analysis.

BACKGROUND: Corticosteroid administration before elective extubation has been used to prevent postextubation stridor and reintubation. We updated a systematic review to identify which patients would benefit from prophylactic corticosteroid administration before elective extubation. METHODS: We searched PubMed, EMBASE, the Wanfang Database, the China Academic Journal Network Publishing Database, and the Cochrane Central Register of Controlled Trials for eligible trials from inception through February 29, 2016. All randomized controlled trials were eligible if they examined the efficacy and safety of systemic corticosteroids given prior to elective extubation in mechanically ventilated adults. We pooled data using the DerSimonian and Laird random-effects model. RESULTS: We identified 11 trials involving 2,472 participants for analysis. Use of prophylactic corticosteroids was associated with a reduced incidence of postextubation airway events (risk ratio [RR], 0.43; 95% CI, 0.29-0.66) and reintubation (RR, 0.42; 95% CI, 0.25-0.71) compared with placebo or no treatment. This association was prominent in participants at high risk for the development of postextubation airway complications, defined using the cuff-leak test, with a reduced incidence of postextubation airway events (RR, 0.34; 95% CI, 0.24-0.48) and reintubation (RR, 0.35; 95% CI, 0.20-0.64). This association was not found in trials with unselected participants. Adverse events were rare. CONCLUSIONS: Administration of prophylactic corticosteroids before elective extubation was associated with significant reductions in the incidence of postextubation airway events and reintubation, with few adverse events. It is reasonable to select patients at high risk for airway obstruction who may benefit from prophylactic corticosteroids.

Computational modeling of tracheal angioedema due to swelling of the submucous tissue layer.

Angioedema is a tissue-swelling pathology due to rapid change in soft tissue fluid content. Its occurrence in the trachea is predominantly localized to the soft mucous tissue that forms the innermost tracheal layer. The biomechanical consequences, such as airway constriction, are dependent upon the ensuing mechanical interactions between all of the various tissues that comprise the tracheal tube. We model the stress interactions by treating the trachea organ as a three-tissue system consisting of swellable mucous in conjunction with nonswelling cartilage and nonswelling trachealis musculature. Hyperelastic constitutive modeling is used by generalizing the standard anisotropic, incompressible soft tissue framework to incorporate the swelling effect. Finite element stress analysis then proceeds with swelling of the mucous layer providing the driving factor for the mechanical analysis. The amount of airway constriction is governed by the mechanical interaction between the three predominant tissue types. The detailed stress analysis indicates the presence of stress concentrations near the various tissue junctions. Because of the tissue's nonlinear mechanical behavior, this can lead to material stiffness fluctuations as a function of location on the trachea. Patient specific modeling is presented. The role of the modeling in the interpretation of diagnostic procedures and the assessment of therapies is discussed.

Cuff-leak test combined with interventional bronchoscopy benefits early extubation for patients who received tarp surgery.

PURPOSE: This study explored the performance characteristics of a cuff-leak test (CLT) combined with interventional fiberoptic bronchoscopy (FBS) for evaluating whether early nasoendotracheal extubation was possible for patients who had received transoral atlantoaxial reduction plate (TARP) internal fixation surgery. METHODS: 318 patients who underwent surgery were retrospectively analyzed (between January 2006 and December 2012). Extubation was performed by conventional approach (CA group, until December 2008) and improved approach (IA group, from January 2009) including CLT and an interventional FBS procedure. The extubation success within 1-3 days after surgery, incidence of postextubation stridor and tracheal reintubation were examined. RESULTS: More IA-treated patients experienced extubation during the first 2 days than those CA-treated, median extubation time was 3 (2, 3) days in the CA group and 2 (1, 2) days in the IA group (all P < 0.01). The incidence of stridor and reintubation was 5.69 and 0.57 % in IA and 11.98 and 4.93 % in CA, respectively (both P < 0.05). For the CLT-positive patients in the IA group that remained intubated until day 3-4, interventional FBS was applied for safe extubation and achieved 100 % success. CONCLUSION: Early extubation through IA is safe and interventional FBS assists successful extubation for CLT-positive patients who underwent TARP surgery.

Laryngeal air column width ratio in predicting post extubation stridor.

AIM: Correlation of upper air column width ratio in postextubation stridor patients. MATERIALS AND METHODS: A prospective observational study was conducted in a tertiary hospital between January and December 2013. Patients who were admitted in Intensive Care Unit and intubated for >24 h were included (72 patients). The upper airway air column width ratio (air column width before extubation/air column width after intubation) was calculated and compared in patient with or without postextubation stridor. RESULTS: The incidence of stridor was 6.9% (5/72). The duration of mechanical ventilation was 5.60 ± 1.14 days and 3.91 ± 1.45 days in stridor and nonstridor group respectively. In all 5 patients who had stridor, the upper airway air column width ratio was 0.8 or less. CONCLUSION: Air column width ratio of 0.8 or less may be helpful in predicting postextubation stridor, which should be confirmed by large observational studies.

Laryngeal ultrasonography versus cuff leak test in predicting postextubation stridor.

INTRODUCTION: Although cuff leak test has been proposed as a simple method of predicting the occurrence of postextubation stridor, cut-off point of cuff-leak volume substantially differs between previous studies. In addition, laryngeal ultrasonography including measurement of air column width could predict postextubation stridor. The aim of the present study was to evaluate the value of laryngeal ultrasonography versus cuff leak test in predicting postextubation stridor. METHODS: In a prospective study, all patients intubated for a minimum of 24 h for acute respiratory failure, airway protection and other causes were included. Patients were evaluated for postextubation stridor and need for reintubation after extubation. The cuff leak volume was defined as a difference between expiratory tidal volumes with the cuff inflated and deflated. Laryngeal air column width was defined as the width of air passed through the vocal cords as determined by laryngeal ultrasonography. The air-column width difference was the width difference between balloon-cuff inflation and deflation. RESULTS: Forty one intubated patients with the mean age of 57.16±20.07 years were included. Postextubation stridor was observed in 4 patients (9.75%). Cuff leak test (cut off point: 249 mL) showed sensitivity and specificity of 75% and 59%, respectively. In addition, laryngeal ultrasonography (cut off point for air column width: 10.95 mm) resulted in sensitivity and specificity of 50% and 54%, respectively. Positive predictive value of both methods were <20%. CONCLUSION: Both cuff leak test and laryngeal ultrasonography have low positive predictive value and sensitivity in predicting postextubation stridor and should be used with caution in this regard.

Predicting laryngeal edema in intubated patients by portable intensive care unit ultrasound.

PURPOSE: The purpose of this study is to determine the diagnostic accuracy of portable ultrasound for detection of laryngeal edema (LE) in intubated patients. MATERIALS AND METHODS: We conducted a prospective, observational study from December 2010 to September 2011. We measured air column width differences (ACWD) in planned extubation patients admitted in intensive care unit by ultrasound. The primary outcome was the diagnostic accuracy of ACWD to predict the presence of LE. RESULTS: A total of 101 patients were enrolled. The prevalence of LE was 16.8%. Baseline characteristics were similar between intubated patients with and without LE. The mean difference of increasing of air column width in patients without LE was higher than in LE group (1.9 vs 1.08 mm, P<.001). The sensitivity and specificity at ACWD higher or equal to 1.6 mm were 0.706 and 0.702, respectively. The positive predictive value and negative predictive value were 0.324 and 0.922, respectively. The area under the receiver operating characteristic curve of laryngeal ultrasound was 0.823 (95% confidence interval, 0.698-0.947) and that of cuff leak test was 0.840 (95% confidence interval, 0.715-0.964). CONCLUSION: Portable intensive care unit ultrasound visualizing ACWD between predeflation and postdeflation cuff balloon is a promising objective tool, which aids in prediction of successful extubation regarding LE.