4. Discussion
Our findings suggest that closed-PICU perioperative management by
pediatric intensivists results in a significant increase in the 28-day
VFD and reduction in the length of postoperative PICU stay of CTS
patients.
The median 28-day VFD was longer in the closed-PICU group than in the
open-PICU group. This is likely to be attributable to the changes in the
preoperative and postoperative respiratory management policies. The
introduction of the sedation scale may have contributed to this result.
In terms of preoperative respiratory management, more patients in the
open-PICU group were intubated until surgery. Fewer patients underwent
preoperative mechanical ventilatory management in the closed-PICU group
due to inclusion of cases transferred from other hospitals, in whom
extubation was difficult. However, they were successfully extubated in
our hospital, thus allowing management in the PICU without a mechanical
ventilator until surgery. In the closed-PICU group, we achieved a
shortened duration of postoperative muscle relaxant administration by
controlling the degree of sedation stringently using a newly introduced
sedation scale. We also worked aggressively to ensure the use of
appropriate ventilatory support devices to reduce the effort of
breathing after extubation. These devices were used in 89% of patients
in the closed-PICU group compared to only 39% of patients in the
open-PICU group. In the perioperative management of CTS, we assumed that
ventilator-induced diaphragmatic dysfunction10,11 was
always present due to long-term preoperative mechanical ventilatory
management, diaphragmatic immobilization secondary to postoperative use
of muscle relaxants, and increased airway resistance due to
postoperative tracheal edema. Furthermore, the increased respiratory
rate and secretions due to crying increased the relative airway
resistance, thereby resulting in an increase in respiratory effort.
Sedation management was essential in preventing crying; however, the
difficulties encountered in the removal of secretions due to
over-sedation could have resulted in ventilation failure. These changes
in perioperative respiratory management, including the introduction of a
sedation scale and early rehabilitation, may have been the reasons
behind the increase in the 28-VFD of the closed-PICU group.
The length of postoperative PICU stay was significantly shorter in the
closed-PICU group. A prolonged PICU stay increases the risk for delirium
in children12; hence, shortening ICU stay is
beneficial to patients and may help curb their hospitalization costs.
The presence of a pediatric intensivist in the PICU was associated with
lower patient mortality, duration of mechanical ventilation, length of
PICU stay, and hospital-acquired infections7.
Additionally, a 24-hour shift of pediatric intensivists in the PICU are
associated with reduction the duration of mechanical ventilation and
length of ICU stay as compared with a 12-hour shift13.
Our study corroborated the finding that the 24-hour shift of pediatric
intensivists reduced the length of postoperative PICU stay. One possible
explanation is the improved adherence to guidelines by the
intensivists14. The guidelines of the European Society
of Intensive Care Medicine15 recommend early
initiation of enteral feeding in patients with controlled hypoxemia,
hypercapnia, and acidosis. Furthermore, the guidelines also recommend
against delays in the initiation of nutrition when using muscle
relaxants. In this study, enteral feeding was started earlier in the
closed-PICU group, suggesting that pediatric intensivists may have been
managing patients in compliance with the guidelines.
Additionally, we trained the teams in resuscitation and ECMO
trouble-shooting simulations to respond to emergency situations better.
Perioperative management of CTS patients by a multidisciplinary team
significantly reduces the length of PICU stay, thereby reducing the cost
of treatment16. In this study, CPR events occurred in
10% of the patients after CTS surgery. This suggested the importance of
creating teams that were well trained in emergency response procedures
such as extracorporeal cardiopulmonary resuscitation (ECPR). One case in
each group of our study required postoperative ECPR; the patient in the
open-PICU group died, whereas the one in the closed-PICU group survived.
For conditions like CTS, where multiple professionals are involved and
postoperative management or care is complex, management by a
multidisciplinary team may have led to a shorter PICU stay. The
mortality rate in our study (2%) is comparable with those seen in
previous reports (5–13%)17-19. Furthermore, our
results are comparable to those of a previous report by Butler et
al.20, which has the largest study sample (n=101).
There were no deaths in the closed-PICU group, suggesting that our team
was well trained and well equipped in responding to sudden events
adverse such as postoperative ventilation failure and cardiac arrest.
CTS is a rare disease, and only a few large-scale studies have been
published20,21. These studies have mainly evaluated
surgical management, but, to the best of our knowledge, only one
report16 focused on perioperative management. Only a
few studies have demonstrated the benefits of being managed by a
pediatric intensivist. These studies have studied heterogeneous
populations because the target population has included all patients
admitted to the PICU7,13. This study, to the best of
our knowledge, is the first to observe the impact of pediatric
intensivists on patient outcomes in a relatively large and homogeneous
population despite the rare prevalence of CTS.
This study had some limitations. First, the sample size was small, and
there were missing data in the open-PICU group. Nosocomial infections
such as ventilator-associated pneumonia were important factors affecting
patient outcomes; however, surveillance was not available in the
open-PICU group. Additionally, data on detailed ventilator settings were
not available in the medical records. The second limitation is the
pre–post comparison design of this study. Changes in intraoperative
management and improvement in surgical techniques have resulted in
shortened duration of mechanical ventilation management and decreased
mortality20,22. However, we attempted to minimize the
impact of changes over time by limiting the study to patients undergoing
slide tracheoplasty and by only including cases that had undergone
surgery in the year prior to the change in PICU management in the
open-PICU group. Finally, there was a lack of patient matching by
severity of illness. Preoperative ECMO management20,
low body weight, and younger age21 have been reported
to be risk factors for death. Preoperative ECMO management was not
performed in either group, and there were no significant differences in
weight and age. The number of patients who had been intubated until
surgery was significantly higher in the open-PICU group than in the
closed-PICU group. This was probably related to the change in attempting
extubation and enabling the growth of the patients until better
operative conditions, as far as could be safely achieved, were
available. In addition, details regarding bronchial morphology, such as
the difference between the left and right bronchial diameters (bronchial
mismatch)23 and surgical
technique24, were not analyzed.
Additionally, the presence of confounding factors cannot be excluded due
to the retrospective design of the study. Future prospective studies
with more participants are recommended to overcome these limitations.