CPAP in Liver Transplant

  • STATUS
    Recruiting
  • participants needed
    80
  • sponsor
    University of Turin, Italy
Updated on 7 November 2020

Summary

The purpose of this study is to determine the effectiveness of continuous positive airway pressure compared to standard treatment in preventing the need for intubation and mechanical ventilation in patients who develop acute hypoxemia after liver transplant. Hypoxemia complicates the recovery of 30-50 % of patients after abdominal surgery; endotracheal intubation and mechanical ventilation may be required in 8-10 % of cases increasing morbidity and mortality and prolonging intensive care unit and hospital stay.

Description

Recovery from abdominal surgery is usually fast and uncomplicated but postoperative hypoxemia complicates 30-50 % of cases even in uneventful procedures (1). Although oxygen administration and incentive spirometry are effective in treating the vast majority of postoperative hypoxemia cases (2), respiratory failure may occur early in the postoperative course (3) requiring endotracheal intubation and mechanical ventilation in 8-10 % of patients thus increasing morbidity and mortality and prolonging intensive care unit and hospital stay (1-4). Loss of functioning alveolar units has been recognized as the underlying mechanism responsible for postoperative hypoxemia (5-7); pulmonary atelectasis after abdominal surgery is, in fact, common, it may exceed 25 % of the total lung volume and is seen several days after surgery (5-7). Continuous positive airway pressure (CPAP) is a breathing mode where the patient spontaneously breathes through a pressurized circuit against a threshold resistor that maintains a preset positive airway pressure during both inspiration and expiration. Although several studies have demonstrated the efficacy of CPAP to reduce atelectasis and improve oxygenation in patients after abdominal surgery (8-11), no clinical trials have confirmed that the improvement of gas exchange with CPAP actually results in a reduced need for intubation and mechanical ventilation in patients who develop hypoxemia after abdominal surgery (12). We conducted a multi-center, prospective, randomized clinical trial to compare the efficacy of CPAP with standard oxygen therapy in the treatment of postoperative hypoxemia. The present study set out to examine the hypothesis that early application of CPAP may prevent intubation and mechanical ventilation in patients who develop acute hypoxemia after liver transplant. Concealed randomization was conducted centrally through a dedicated web site using a computer-generated block randomization schedule. Patients were randomized to be treated for six hours with oxygen through a Venturi mask at a FiO2 of 0.5 (control) or with oxygen at a FiO2 of 0.5 plus a CPAP of 7.5 cm H2O (CPAP). At the end of the 6-hour period, patients passed a one-hour screening test breathing oxygen through a Venturi mask at a FiO2of 0.3. Patients returned to the assigned treatment if the PaO2/FiO2 ratio was less than or equal to 300; treatment was interrupted if the PaO2/FiO2 ratio was higher than 300. Nasal oxygen (8-10 liter/minute) was given if the treatment was not tolerated (Figure 1). In all centers, CPAP was generated using a flow generator with an adjustable inspiratory oxygen fraction set to deliver a flow of up to 140 liters per minute (Whisperflow, Caradyne, Ireland) and a spring-loaded expiratory pressure valve (Vital Signs Inc, Totoma NJ) and applied using a latex-free polyvinyl chloride transparent helmet (CaStar, Starmed, Italy) (15); all centers measured the inspiratory oxygen fraction using an oxygen analyzer (Oxicheck, Caradyne, Ireland) through the Venturi mask or the helmet. All analyses were conducted on an intention-to-treat basis. Values are reported as mean and standard deviation. Continuous variables were compared with the use of the unpaired t-test or the Wilcoxon rank-sum test, depending on their distributional characteristics. Categorical variables were compared with the use of Fisher's exact test or the chi-square test, when appropriate. The Kaplan-Meier curve for intubation rate was plotted and was compared by the log-rank and Wilcoxon tests. All reported P values are two-sided.

Details
Condition Hypoxia
Treatment CPAP application
Clinical Study IdentifierNCT00510770
SponsorUniversity of Turin, Italy
Last Modified on7 November 2020

Eligibility

How to participate?

Step 1 Connect with a site
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar
Name

Primary Contact

site
Name

0/250
Preferred Language
Other Language
Please verify that you are not a bot.

Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider

Loading...

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 

 • 

Private

Reply by • Private
Loading...

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.
Loading...

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note