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

Fatores associados à falha de extubação em unidade de terapia intensiva: estudo de caso-controle

Resumo Objetivo: investigar os fatores associados à falha de extubação de pacientes na unidade de terapia intensiva. Método: caso-controle não pareado, longitudinal, retrospectivo e quantitativo com a participação de 480 pacientes por meio de parâmetros clínicos para desmame ventilatório. Dados analisados por: Teste Exato de Fisher ou o teste Qui-quadrado; teste t de Student bicaudal não pareado; e teste de Mann-Whitney. Admitiram-se significantes valores de P menores ou iguais a 0,05. Resultados: dos pacientes, 415 (86,5%) tiveram sucesso e 65 (13,5%) falharam. Grupo sucesso: balanço hídrico mais negativo, APACHE II em 20 (14-25), tosse fraca em 58 (13,9%). Grupo falha: balanço hídrico mais positivo, APACHE II em 23 (19-29), tosse fraca em 31 (47,7 %), quantidade abundante de secreção pulmonar em 47,7 %. Conclusão: o balanço hídrico positivo e a presença de tosse ineficiente ou incapacidade de higienizar a via aérea foram preditores de falhas de extubação.

Factors associated with extubation failure in an intensive care unit: a case-control study

Abstract Objective: to investigate the factors associated with extubation failure of patients in the intensive care unit. Method: unpaired, longitudinal, retrospective and quantitative case-control with the participation of 480 patients through clinical parameters for ventilator weaning. Data were analyzed by: Fisher’s exact test or the chi-square test; unpaired two-tailed Student’s t test; and Mann-Whitney test. Significant P values lower than or equal to 0.05 were admitted. Results: of the patients, 415 (86.5%) were successful and 65 (13.5%) failed. Success group: the most negative fluid balance, APACHE II in 20 (14-25), weak cough in 58 (13.9%). Failure group: the most positive fluid balance, APACHE II in 23 (19-29), weak cough in 31 (47.7%), abundant amount of pulmonary secretions in 47.7%. Conclusion: positive fluid balance and the presence of inefficient cough or inability to clear the airway were predictors of extubation failure.

Factores asociados al fracaso de la extubación en unidad de cuidados intensivos: estudio de caso y control

Resumen Objetivo: investigar los factores asociados al fracaso de la extubación de pacientes en la unidad de cuidados intensivos. Método: caso y control no apareado, longitudinal, retrospectivo y cuantitativo con la participación de 480 pacientes mediante parámetros clínicos para el destete de la ventilación. Datos analizados por: Prueba Exacta de Fisher o prueba de Chi-cuadrado; prueba t de Student de dos colas para datos no apareados; y prueba de Mann-Whitney. Se admitieron valores de P significativos menores o iguales a 0,05. Resultados: de los pacientes, 415 (86,5%) tuvieron éxito y 65 (13,5%) fracasaron. Grupo de éxito: balance hídrico más negativo, APACHE II en 20 (14-25), tos débil en 58 (13,9%). Grupo de fracaso: balance de líquidos más positivo, APACHE II en 23 (19-29), tos débil en 31 (47,7%), abundante cantidad de secreciones pulmonares en 47,7%. Conclusión: el balance hídrico positivo y la presencia de tos ineficaz o incapacidad para higienizar la vía aérea fueron predictores de fracaso de la extubación.

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

Cuff Leak Test and Airway Obstruction in Mechanically Ventilated ICU Patients: A Pilot Randomised Controlled 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).

OBJECTIVE

Given the uncertainty of the CLT's clinical utility, we conducted the Cuff Leak Test and Airway Obstruction in Mechanically Ventilated ICU Patients (COMIC) pilot study to examine the feasibility of undertaking a larger trial.

METHODS

COMIC is a multicentred, parallel-group randomised trial performed in Canada, Saudi Arabia, and Poland. We enrolled mechanically ventilated adults admitted to the intensive care unit (ICU) 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 randomised 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 that required reintubation in each group.

CONCLUSION

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 ClinicalTrials.gov (NCT03372707). Registered December 14th, 2017, https://clinicaltrials.gov/ct2/show/NCT03372707.

Acute Macroglossia Post Craniotomy in Sitting Position: A Case Report and Proposed Management Guideline

Background

Macroglossia is a rare life-threatening postoperative complication in patients undergoing neurosurgical operations in a sitting position. It is difficult to identify the cause of macroglossia, which can be considered multifactorial in most patients.

Case Presentation

We herein present a case of a 37-year-old female patient who was known to have a posterior occipital lesion (low-grade glioma with pilocytic features) and underwent occipital craniectomy followed by supratentorial approach for debulking of the tumor under general anesthesia in a sitting position. The patient developed upper airway edema along with extreme macroglossia immediately following extubation, with increasing difficulty in ventilation. Re-intubation was impossible, and urgent tracheostomy was performed. In the intensive care unit (ICU), the macroglossia worsened, and the patient developed sepsis with multi-organ failure and died 16 days postoperatively.

Conclusion

Acute macroglossia can be a catastrophic postoperative complication, necessitating early identification and a systematic approach to this critical event, in addition to being fully prepared to deal with difficult airway should this complication occur.