Endotracheal Cuff Pressure Clinical Trial
Official title:
Comparison Between Two Endotracheal Tube Cuff Inflation Methods; Flow Volume Loop Guided vs. Just Seal by Stethoscope Guided in Pediatric Patients
This study is a prospective randomized controlled trial, the primary aim of this study to
compare the intracuff pressure which is performed by 2 inflation methods. ( study in
pediatric patients 4-12 year old) Group1 : Flow -Volume Loop-guided cuff inflation Group2 :
Stethoscope-guided cuff inflation Our hypothesis is Flow-Volume Loop-guided cuff pressure
will be lower than Stethoscope-guided cuff pressure.
This study also collect the incidence of common post-extubation respiratory adverse events
coughing, hoarseness, stridor, croup as an secondary outcomes.
Historically, pediatric anesthesiologists abstained from using cuff-endotracheal tubes in
children younger than 8 year of age because of the anatomical particularises of their airway
and thus the increased risk of postintubation tracheal damage especially when Nitrous oxide
is used for long procedures. In addition the tube size shoud be half size reduced when cuffed
endotracheal tube is used, leading to higher airway resistance and increased risk of tube
obstruction.
Recently, the use of Cuffed endotracheal tube has been increasing in children younger than 8
year of age who undergoing general anesthesia. Due to several reasons as follows 1) an
increasingly sophisticated understanding of developing laryngeal anatomy 2) vastly improved
materials in the manufacture of endotracheal tubes 3) cuffed endotracheal tubes serve several
advantages over uncuffed endotracheal tubes including fewer laryngoscopies to replace
ill-fitting tubes, less contamination of operating room with anesthetic gases, reliable
capnography monitoring, better protection against aspiration, adequate ventilation with a low
fresh gas flow which allow using low flow anesthsia, and also they are advantageous for
certain operations such as laparoscopic/ airway procedures. 4) data are plentiful supporting
the equal safety of using cuffed endotracheal tubes compared with uncuffed tubes in children
However, using cuffed endotracheal tubes without being careful of cuff pressure may result in
damage to tracheal mucosal wall especially in pediatric patients. The intra-cuff pressure
should be monitored and maintained at the level below 25 cm H2O. The intra-cuff pressure more
than 30 cmH2O causes obstruction to mucosal blood flow and increasing the risk of airway
mucosal injury. Cuff pressure measurement by manometer is a gold standard, nevertheless
manometer is not available in every operating room. Almost of anesthetists often use either
manual palpation of pilot balloon or stethoscope-guided to inflate endotracheal tube cuff.
In adult studies, they found that endotracheal tube cuff pressure estimated by palpation even
with experience personals is often much higher than 25-30 cmH2O. Therefore this inflation
technique should be avoided in pediatric patients.
As for, stethoscope-guided endotracheal cuff inflation which pediatric anesthesiologists
usually use for children. There were several studies in adult patients, they found the median
cuff pressure from this inflation technique was 20 (16-28) cmH2O which is in acceptable
tracheal cuff pressure.
In routine practice of general anesthesia rarely have continuous cuff pressure monitoring.
When Nitrous Oxide is used for general anesthesia, the intra-cuff pressure can increase with
time. Accordingly, it will be better to keep intra-cuff pressure as low as having proper
sealing.
A couple studies from adult, compared endotracheal tube cuff inflation techniques between
Pressure-Volume(PV) loop guided and stethoscope-guided and the results were intra-cuff
pressure from PV loop guided was less than stethoscope guided. Moreover cuff-related
complications ( coughing, sorethroat) were less in PV loop group also. It seems PV loop
guided can provide least cuff pressure with efficient sealing.
This study would like to compare endotracheal cuff pressure that are performed by 2
techniques between Flow-Volume(FV) loop guided and stethoscope-guided in pediatric patients
Intra-cuff pressure will be the primary outcome and we will also collect postoperative
respiratory complications such as coughing, stridor, hoarseness as secondary outcomes.
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