|Year : 2021 | Volume
| Issue : 1 | Page : 26-34
Current practice and attitudes regarding the perioperative use of cuffed tracheal tubes for pediatric and neonatal tracheal intubation: A survey-based evaluation among Indian anesthesiologists
Poonam Motiani1, Zainab Ahmad2, Pramod Kumar Sharma3, Anju Gupta4, Mukul Kumar Jain1, Dinesh Kumar Sahu1
1 Department of Paediatric Trauma and Anaesthesia, Superspeciality Paediatric Hospital and Postgraduate Teaching Institute, Noida, Uttar Pradesh, India
2 Department of Anesthesiology and Critical Care, AIIMS, Bhopal, Madhya Pradesh, India
3 Department of Paediatric Surgery, AIIMS, Bhopal, Madhya Pradesh, India
4 Department of Anesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, Delhi, India
|Date of Submission||30-Aug-2020|
|Date of Decision||06-Oct-2020|
|Date of Acceptance||03-Nov-2020|
|Date of Web Publication||22-Feb-2021|
Dr. Anju Gupta
Room No. 6, 4th Floor, Porta Cabin, Teaching Block, Department of Anesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, Delhi-110 029
Source of Support: None, Conflict of Interest: None
Introduction: the use of cuffed endotracheal tubes (ETTs) in children is debatable. Despite recent literature on the use of cuffed ETT in children, its use is relatively low even in developed world. We conducted this survey to explore the perceptions and patterns of cuffed/uncuffed ETT usage in children, <5 years of age.
Materials and Methods: This descriptive cross-sectional survey was done using a specially designed Google Form that was circulated among anesthesiologists of any grade practicing in India. The questionnaire was validated by seven experts on a 4-point scale as per the standardized model of content validity index and those with an index <0.78 were modified. Thereafter, the questionnaire was circulated over a month through WhatsApp and a reminder was sent every week for a month.
Results: The total response rate was 55% (99/180) and after excluding the responses of postgraduates, 96 responses were evaluated. The use of pediatric cuffed ETT was similar among institutions. Only 35.5% of the respondents routinely used cuffed tubes regularly. The common reasons for nonusage of cuffed tubes included fear of higher resistance to flow and risk of subglottic injury. Those anesthesiologists who were performing higher pediatric cases were more inclined to use a cuffed ETT. Endotracheal cuff pressure was monitored routinely by 40% of the respondents who used cuffed tube.
Conclusion: Anesthesiologists practicing pediatric anesthesia are more likely to choose cuffed ETT in children aged <5 years. Safety norms such as cuff pressure monitoring are not being followed routinely when these tubes are used.
Keywords: Children, cuffed endotracheal tube, neonates, survey
|How to cite this article:|
Motiani P, Ahmad Z, Sharma PK, Gupta A, Jain MK, Sahu DK. Current practice and attitudes regarding the perioperative use of cuffed tracheal tubes for pediatric and neonatal tracheal intubation: A survey-based evaluation among Indian anesthesiologists. Indian Anaesth Forum 2021;22:26-34
|How to cite this URL:|
Motiani P, Ahmad Z, Sharma PK, Gupta A, Jain MK, Sahu DK. Current practice and attitudes regarding the perioperative use of cuffed tracheal tubes for pediatric and neonatal tracheal intubation: A survey-based evaluation among Indian anesthesiologists. Indian Anaesth Forum [serial online] 2021 [cited 2021 May 9];22:26-34. Available from: http://www.theiaforum.org/text.asp?2021/22/1/26/309747
| Introduction|| |
For years, the use of cuffed or uncuffed endotracheal tubes (ETTs) in children has been a matter of debate. The increased body of evidence is now leaning toward cuffed ETTs (CETs) due to advantages in the form of reduced theater contamination with anesthetic gas, decreased ETT exchanges, increased capnographic accuracy, and decreased risk of microaspiration and respiratory adverse events,, without increasing the risk of any airway morbidity.,,
Organizations such as the American Heart Association, the International Liaison Committee on Resuscitation, and the European Resuscitation Council have accepted CETs as an acceptable alternative to non-CETs in their latest guidelines for cardiopulmonary resuscitation of infants and children.,, Improvement in the design of CETs has made these tubes safer than ever for this population. Since 2004, a high-volume, low-pressure CET specifically designed for children has been made available (MicroCuff®, Kimberly-Clark, unomedical sdn, Kedah, Malaysia), which has been found to effectively seal the trachea at very low pressures (<15 cmH2O) and since then, there have been substantial data which support their use. The Paediatric Difficult Intubation Collaborative (PeDI-C) has recently come up with the Consensus Guidelines for Airway Management in pediatric COVID-19 patients. They have also recommended CETs to secure the airway in children with COVID-19 and have advocated that micro-CETs should be preferred for those < 6 years of age.
Despite the developing consensus in the literature and increased evidence favoring their use, there still appears to be a surprisingly low utilization rate of CETs in pediatric anesthesia (PA) in Western countries. We decided to investigate/ascertain the most recent attitudes and practices of pediatric endotracheal intubation preferences among Indian anesthesiologists. Specialist airway managers working in various government and private multispecialty teaching hospitals and specialist centers in India were targeted as we believe that any widespread change in practice is likely to follow the lead of such skilled leaders.
We aimed to explore the perceptions and patterns of cuffed/uncuffed ETT usage in children, <5 years of age and in neonates and to ascertain if the pattern of usage was influenced by an anesthesiologist's experience or by the proportion of their workload comprising of pediatric patients or by the occurrence of any complications. In addition, we intended to determine whether safety norms such as cuff pressure measurement are being adhered to by those using CETs in this population. To our knowledge, till date, there is no such data from the Indian population documenting the preferences of anesthesiologists about the usage of CETs for pediatric patients undergoing various types of surgery.
| Materials and Methods|| |
We performed a thorough search on PubMed and Google Scholar focusing on practice guidelines. Questions were constructed after identifying variables from previous studies, review articles, and practice guidelines on this topic, following a review of the literature. A mixed qualitative/quantitative approach was used to design this anonymous self-structured questionnaire.
A panel of qualified airway managers reviewed the questionnaire, and 15 questions were shortlisted by consensus which included questions regarding the profile of respondents and the use of CETs [Appendix A]. Subsequently, an Excel sheet was prepared for an expert group to grade each question on a 4-point scale and was mailed to ten experts. Seven of the ten experts completed the assessment and grading as per a standardized model of content validity index (CVI). If the item level content validation index (I-CVI) was <0.78, the question was reviewed accordingly.
The self-structured online questionnaire was sent over a month (from February 16, 2020 to March 15, 2020) as a Google Form to Indian anesthesiologists (consultants and residents) who were members of various WhatsApp groups consisting of either skilled airway instructors or those belonging to PA groups. After eliminating duplicate numbers for single person and some nonanesthesiologists, 180 such anesthesiologists were identified. A brief mention of the need for the survey and information to the participants was included in the beginning so that the participants were aware about the nature of the survey. The participation of anesthesiologists in this study was on a voluntary basis. By clicking on the link, it was assumed that the respondents have consented to participate in the survey. The survey did not include any question that could disclose the participant's or the institute's identity. On receiving and clicking the link, the participants were auto-directed to the Google Form. After filling the demographic details, a set of questions appeared sequentially, which were mandatory for the participants to answer. A closed multiple-choice design for the questionnaire had been selected to exclude the possibility of interpretational errors.
The survey link was re-sent weekly for 1 month on the groups and also on personal WhatsApp numbers, as a reminder for nonresponders. To avoid duplication of responses, participants were required to fill in their E-mail addresses in the Google Form and the Google Sheet accepted only one response from a particular mail.
The data were collected and entered into the Statistical Package for Social Sciences Version 19 (IBM SPSS Statistics, Chicago, IL, USA). Descriptive statistics were used to analyze the characteristics of the study sample and to review overall responses to the questions. Percentages were used in the data analysis. In testing associations for categorical variables, Pearson's Chi-square tests for independence was performed. P < 0.05 was considered statistically significant. Appropriate statistical tests were applied to study the quantitative and qualitative aspects of the study.
To find out sample size to analyze the preference of cuffed tube (p) over uncuffed tube (q), P was assumed equal to q as 50%, so the sample size at 95% confidence interval (CI), with 80% power and assuming an absolute precision of 10%, was calculated using the following formula: n = z × z × p × q/d × d, where P = q = 50%, z value at 95% CI = 1.96, and d = absolute precision. After substituting the values in the formula, a sample size of 96 was obtained, which was rounded off to obtain a sample size of 100.
| Results|| |
Replies were received from 99 out of the 180 eligible participants (55% response rate). After excluding responses from postgraduate students, a total of 96 questionnaires were evaluated.
Overall 50% of replies were received from medical colleges, 18.75% from autonomous institutes, and 21.87% from corporate hospitals [Table 1]. The general profile of the respondents is mentioned in [Table 1]. There was no statistically significant difference (P = 0.32) in the pattern of pediatric CETs usage among these institutions.
Among the 96 respondents, only 35.41% (n = 34) routinely used and 42.7% (n = 41) did not use CETs in children < 5 years, undergoing surgeries, with an indication of endotracheal intubation. The rest (21%) of the participants affirmed that they would like to use CETs if available [Table 2]. Majority of the respondents (70.9%, n = 39/55) chose the option “all of the above” as the reason for using CETs, comprising the use of lower fresh gas flow, improved ventilation, and end-tidal carbon dioxide monitoring; less use of inhalational agent, therefore economical, reduced air pollution; reduced risk of aspiration; and avoidance of multiple laryngoscopies and intubations [Table 3].
|Table 2: Frequency of usage of cuffed endotracheal tubes in children less than 5 years, excluding neonates|
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|Table 3: Most appropriate reasons for the usage of cuffed endotracheal tube in pediatric cases|
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The most common reason for nonusage of CETs, identified by 54.54% (n = 30/55) of the respondents, was “both” comprising – “uncuffed ETT allows larger internal diameter (ID) and lower resistance to airflow” and “uncuffed ETT in children avoids trauma to sub-glottic region” [Table 4].
|Table 4: Most appropriate reasons for the nonusage of cuffed endotracheal tube in pediatric cases|
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Of the 96 respondents, 73.95% (n = 71) had >5 years, while 25% (n = 24) had ≤5 years' experience in anesthesia practice [Figure 1]. Those with >5 years' experience used CETs much more frequently (40.8%; n = 29/71) than those with <5 years of experience (16.66%; n = 4/24). However, these differences failed to reach statistical significance (P = 0.35). There was a statistically significantly higher usage of CETs, in children <5 years, by faculty/consultants (85.3%, n = 29/71) as compared to residents (38.5%, n = 5/24) (P = 0.005) [Figure 2].
|Figure 1: Correlation between respondents' years of post-postgraduate experience in anesthesia with pattern of cuffed endotracheal tube usage, in children <5 years, perioperatively|
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|Figure 2: Pattern of cuffed endotracheal tube usage in children < 5 years, perioperatively with respect to anesthesiologists' current position in the institute|
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Our survey also showed a higher, but not statistically significant (P = 0.165), use of CETs by anesthesiologists, with higher experience in PA practice (41.5% >5 years [n = 22]; 37.03% 1–5 years [n = 10]; and 15.38% <1 year [n = 2]) [Figure 3].
|Figure 3: Comparison of pattern of use of cuffed endotracheal tube, in children <5 years, perioperatively, based on anesthesiologists' post-postgraduate experience in pediatric anesthesia|
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The survey also revealed a significantly higher usage of CETs, in children <5 years, in respondents performing higher number of pediatric cases per month (P = 0.012) [Figure 4]. There was a significantly weak negative correlation between the number of pediatric cases performed per month with the nonusage of CETs or usage, if available, of CET (0.014 by Spearman's correlation).
|Figure 4: Pattern of cuffed endotracheal tube usage with respect to anesthesiologists' experience in terms of average number of pediatric cases per month|
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There were fewer respondents who practiced PA (15.6%; n = 15) exclusively as compared to those who did not (84.37%; n = 81). However, there was no statistically significant difference (P = 0.720) within or between the two groups, regarding the practice of CETs, in children <5 years [Figure 5].
|Figure 5: Pattern of cuffed endotracheal tube usage in children <5 years, with respect to exclusive pediatric anesthesia practice|
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Interestingly, respondents' years of experience or designation did not have any bearing on the usage of CETs in neonates (P = 0.68).
In our study, only 19.7% (n = 19) of the respondents had witnessed a complication with the use of CETs in PA. Further, we found no correlation (P = 0.749) between the incidence of complications with the pattern of CETs usage, in PA. The impact of the use of nitrous oxide in terms of complications encountered with the use of CETs was also not statistically significant (P = 0.086).
Nearly 29.1% (n = 29) of the respondents reported that they always, while 21.8% (n = 21) of the respondents said that they seldom inflated the cuff of the ETT. However, there was no correlation between the practice of inflating the cuff of an ETT intraoperatively, with the perceived incidence of the complications (P = 0.428).
Almost 40.6% (n = 39) of the respondents always, 30.2% (n = 29) never, and 28.1% (n = 27) sometimes monitored the intracuff pressure using a manometer intraoperatively. Further, there was also no correlation between the practice of monitoring intracuff pressure intraoperatively, with the perceived incidence of complications (P = 0.593).
| Discussion|| |
The response rate to our survey was 55%. Our target population for this survey was skilled airway managers and anesthesiologists with special interest in PA as we believe that any widespread change in practice is likely to follow the lead of such specialist airway managers. This survey provides a snapshot of the current practice at various specialist centers in India, with regard to the use of CETs in children.
Conventionally, most pediatric anesthesiologists perform endotracheal intubation using uncuffed tracheal tubes for children up to 8 ± 10 years of age for anesthesia during surgery as well as for prolonged ventilation in intensive care units. The perceived drawbacks of using CETs are the need to use a smaller sized tube, thereby increasing the airway resistance and increased airway mucosal injury., Nonetheless, uncuffed tubes may require multiple laryngoscopies and ETT exchanges; the peritubal leakage may contribute to theater pollution and inadequate ventilation; impede the accuracy of monitored ventilatory parameters, exhaled volumes, and end-expiratory gases; and is uneconomical. These problems, circumvented by CETs, are especially advantageous in laparoscopic surgeries and in patients at increased risk of aspiration. In the ongoing COVID-19 pandemic, it also increases the risk of aerosol exposure to the theater personnel and due to this, PeDI collaborative from the Society of Pediatric Anaesthesia has recommended the use of CETs for children requiring intubation.
Recent advances in the knowledge of pediatric airway anatomy have countered the previous beliefs which favored uncuffed ETTs, and this has further laid impetus on the benefits of CETs in children. Besides, they have been shown to be safe for use even in small neonates.
Despite over a decade of convincing data supporting the use of CETs in PA, our survey revealed that there has been a relatively low rate of adoption of CETs (35%) for routine use in children, <5 years, requiring endotracheal intubation amongst anesthesiologists practicing in India. It still exceeds the overall prevalence reported in previous such studies (a French study [25%], an Ireland survey [25%], and a UK survey of specialist practice [7%],,). The relatively higher frequency of usage in our study as compared to the previous studies is probably due to increasing awareness regarding its benefits and safety in children, easy availability of cuff pressure monitoring devices, and easier availability of CETs including microcuff ETTs nowadays in India. This is consistent with an apparent trend of the increasing utilization of CETs in pediatric patients as reported from a recent 2019 study from Japan and in 2015 from the Netherlands where more than half of the children over 2 years of age were intubated with CETs.,
The overall usage of CETs was lesser in neonates (only 18.7% used whereas 62.5% never did). This figure though much less than that reported from Western countries, is commensurate with the restricted use of CETs for tracheal intubation in neonates.
In all, the faculty and consultants (85.3%) were statistically significantly more frequent users of CETs as compared to the residents (38.46%) (P = 0.005). The survey showed a higher frequency of use of CETs by anesthesiologists, with higher experience in PA practice [Figure 3]. This observance is logical considering the fact that more experienced anesthesiologists or those conducting PA more often would be updated with the recent developments in the field and juniors would be more afraid of making unconventional choices. A similar observation was made in a previous survey from Ireland.
Certain factors were found to have a significantly positive impact on selection of CETs over uncuffed ETT, in neonates. There was a striking increase (63/96; 65.6%) in the proportion of anesthesiologists, selecting a CET if the patient was a neonate at risk of aspiration (P < 0.001). This is commensurate with the recommendation of CET in 2005 Paediatric Advanced Life Support course, which states that a cuffed tracheal tube (TT) is safe as, and may be preferable to, a noncuffed TT in certain emergency circumstances.
Nearly 73% of the respondents had not witnessed any complication with the use of CETs in PA. This is in line with the literature supporting the premise that CETs do not increase the risk of airway morbidity in the form of postextubation stridor, croup, or tracheal stenosis, as compared to the use of uncuffed ETT. This finding is similar to that noticed in previous studies and surveys including those from ICUs with prolonged intubation times.,,
In our survey, 40.6% of the respondents always and 28% sometimes monitored the intracuff pressure, whereas about 30% (n = 29) never monitored the cuff pressure using a manometer intraoperatively. A study from the UK in 2008 had documented a total lack of employment of this monitoring among anesthesiologists using CET in children. Even a recent survey has showed a dismal utilization of cuff pressure monitoring by British anesthesiologists for children (33.2% cases). In pediatric patients, use of CETs with high intracuff pressures can lead to mucosal ischemia and laryngotracheal morbidity. When CETs are used, at a cuff pressure of >40 cmH2O, the incidence of sore throat was found to be around 96%. Hence, use of cuff pressure monitoring has been recommended for safe application of CETs in this age group. Lack of cuff pressure monitors has likewise been cited as one of the hindrances to their widespread use.
A limitation of our study can be that some of the data collected may not be a direct measure of the actual prevalence or adverse events faced. However, because the data were obtained from expert airway managers from across the country, we expect it to be representative of the latest practices being followed at most setups in India. Another limitation can be the possibility of recall bias.
| Conclusion|| |
From our survey, we conclude that consultants and those practicing frequent PA are more likely to choose CET over uncuffed ETTs, perioperatively in children, <5 years, if endotracheal intubation is indicated. The use of CETs is a relatively infrequent practice especially for neonatal anesthesia and safety norms such as cuff pressure monitoring are not being followed routinely when these tubes are used. From the data, it is evident that the awareness regarding the advantages and safety of CETs needs to improve further, and formulating appropriate protocols such as regular use of cuff pressure monitoring is required to prevent any catastrophic complications with their use.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| Appendix|| |
Appendix A Survey questionnaire
The questions regarding the profile of respondents were:
Q1. Years of postgraduate experience in anesthesia practice:
- <1 year
- 1–3 years
- >3–5 years
- >5–10 years
- >10 years
- Would not like to disclose
Q2. Where are you currently working?
- Medical college
- Autonomous institute
- Government nonteaching hospital
- Corporate hospital
Q3. What is your current position in your institute?
Q4. Years of postgraduate experience in pediatric anesthesia practice?
- 1–5 years
- >5 years
Q5. Average number of pediatric cases, excluding neonates, in a month
Q6. Average number of neonatal surgeries in a month
Q7. Do you practice pediatric anesthesia exclusively?
The questions regarding the use of cuffed endotracheal tubes were:
Q8: For surgery, if endotracheal intubation is indicated, do you routinely use cuffed ETTs in children <5 years excluding neonates?
- Would use, if available
Q9: If answer to Q8 is yes, the most appropriate reason is:
- Option 1: Allows use of lower fresh gas flow, improved ventilation, and EtCO2 monitoring
- Option 2: Less use of inhalational agent, therefore economical; reduced air pollution
- Option 3: Reduced risk of aspiration
- Option 4: Avoids multiple laryngoscopies and intubations
- Option 5: All of the above
- Option 6: Options 1 and 2 only
- Option 7: Options 3 and 4 only
Q10: If answer to Q8 is no, the most appropriate reason is:
- Uncuffed ETT allows larger ID and lower resistance to airflow
- Uncuffed ETT in children avoids trauma to subglottic region
- Both of the above
- Classically taught to avoid cuffed ETT in children <8 years
Q11: Do you prefer to use cuffed ETT over uncuffed ETT in neonates?*
Q12. Do you inflate the cuff of the ETT?
- Seldom required
Q13. Do you monitor intracuff pressure intraoperatively using a manometer?
Q14. Do you use N2O along with O2 and inhalational agent for induction in children <5 years, excluding neonates?
Q15: Have you ever witnessed a complication with the use of cuffed ETT in pediatric anesthesia?
- Would not like to disclose
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2], [Table 3], [Table 4]