Cuffed vs. uncuffed tracheal tubes in children: a randomised controlled trial comparing leak, tidal volume and complications

Effect of different lung recruitment strategies and airway device on oscillatory mechanics in children under general anaesthesia

BACKGROUND

Atelectasis has been reported in 68 to 100% of children undergoing general anaesthesia, a phenomenon that persists into the recovery period. Children receiving recruitment manoeuvres have less atelectasis and fewer episodes of oxygen desaturation during emergence. The optimal type of recruitment manoeuvre is unclear and may be influenced by the airway device chosen.

OBJECTIVE

We aimed to investigate the different effects on lung mechanics as assessed by the forced oscillation technique (FOT) utilising different recruitment strategies: repeated inflations vs. one sustained inflation and different airway devices, a supraglottic airway device vs. a cuffed tracheal tube.

DESIGN

Pragmatic enrolment with randomisation to the recruitment strategy.

SETTING

We conducted this single-centre trial between February 2020 and March 2022.

PARTICIPANTS

Seventy healthy patients (53 boys) aged between 2 and 16 years undergoing general anaesthesia were included.

INTERVENTIONS

Forced oscillations (5 Hz) were superimposed on the ventilator waveform using a customised system connected to the anaesthesia machine. Pressure and flow were measured at the inlet of the airway device and used to compute respiratory system resistance and reactance. Measurements were taken before and after recruitment, and again at the end of surgery.

MAIN OUTCOME MEASURES

The primary endpoint measured is the change in respiratory reactance.

RESULTS

Statistical analysis (linear model with recruitment strategy and airway device as factors) did not show any significant difference in resistance and reactance between before and after recruitment. Baseline reactance was the strongest predictor for a change in reactance after recruitment: prerecruitment Xrs decreased by mean (standard error) of 0.25 (0.068) cmH 2 O s l -1 per  1 cmH 2 O -1  s l -1 increase in baseline Xrs ( P  < 0.001). After correcting for baseline reactance, the change in reactance after recruitment was significantly lower for sustained inflation compared with repeated inflation by mean (standard error) 0.25 (0.101) cmH 2 O ( P  = 0.0166).

CONCLUSION

Although there was no significant difference between airway devices, this study demonstrated more effective recruitment via repeated inflations than sustained inflation in anaesthetised children.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12619001434189.

Comparison of preformed microcuff and preformed uncuffed endotracheal tubes in pediatric cleft palate surgery-A randomized controlled trial

BACKGROUND AND AIMS

Airway management in children with oral cleft surgery carries unique challenges, concerning the proximity of the surgical site and the tracheal tube. We hypothesized that using a Microcuff oral RAE tube would reduce tube exchange and migration rate. We aimed to compare the performance of Microsoft and uncuffed oral performed tracheal tubes in children undergoing cleft palate surgeries regarding the rate of tracheal tube exchange, endobronchial intubation, and ventilatory parameters.

METHODS

One hundred children scheduled for cleft palate surgery were randomized into two groups. In the uncuffed group (n = 50), the tracheal tube was selected using the Modified Coles formula, and in the Microcuff (n = 50) group, the manufacturer's recommendations were followed. Intraoperatively, we compared the primary outcome of tube exchange using the chi-square test. The leak pressure and ventilatory parameters after head extension and mouth gag application were measured in both groups.

RESULTS

The tracheal tube exchange rate was significantly lower in the Microcuff group (0/50) than in uncuffed (19/50) preformed tubes (0 vs. 38% respectively; p <.001). The uncuffed and Microcuff tracheal tube were comparable concerning ventilation parameters and leak pressure of finally placed tubes (17.78 ± 3.95 vs. 19.26 ± 3.81 cm H2 O respectively, with a mean difference (95% CI) of -1.48 (-0.01-2.98); p-value =0.059. Cuff pressure did not vary significantly during the initial hour, and the incidence of postoperative airway morbidity between uncuffed and Microcuff tube was comparable, 5/50 (10%) versus 7/50 (14%) with risk ratio (95% CI) of 0.71(0.24-2.1), p value .49.

CONCLUSION

Microcuff oral preformed tubes performed better than uncuffed tubes regarding tube exchange during cleft palate surgery.

Ten-year experience of whole lung lavage in pediatric Pulmonary Alveolar Proteinosis

BACKGROUND

Pulmonary Alveolar Proteinosis (PAP) is extremely rare and can be caused by hereditary dysfunction of the granulocyte macrophage colony-stimulating factor receptor (GM-CSF) receptor, autoantibodies against GM-CSF, or other diseases leading to alveolar macrophage (AM) dysfunction. This leads to protein accumulation in the lung and severe dyspnea and hypoxemia. Whole lung lavage (WLL) is the first line treatment strategy.

METHODS

Here, we present data from more than ten years of WLL practice in pediatric PAP. WLL performed by the use of a single lumen or double lumen tube (SLT vs. DLT) were compared for technical features, procedure time, and adverse events.

RESULTS

A total of n=57 procedures in six PAP patients between 3.5 and 14.3 years of age were performed. SLT based WLL in smaller children was associated with comparable rates of adverse events but with longer intervention times and postprocedural intensive care treatment when compared to DLT based procedures.

DISCUSSION

Our data shows that WLL is feasible even in small children. DLT based WLL seems to be more effective, and our data supports the notion that it should be considered as early as possible in pediatric PAP.

CONCLUSION

WLL lavage is possible in small PAP patients but should performed in close interdisciplinary cooperation and with age appropriate protocols.

Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1C). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1C). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1С). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1С). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO 2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Pre-Extubation Cuffed Tube Leak Test and Subsequent Post-Extubation Laryngeal Edema: Prospective, Single-Center Evaluation of PICU Patients

OBJECTIVES

We performed our standard air leak, leak percentage, and cuff leak percentage tests in pediatric patients intubated with microcuff pediatric tracheal tubes (MPTTs) just before extubation. We examined the association between test findings and the subsequent occurrence of post-extubation laryngeal edema (PLE).

DESIGN

Prospective, single-center, observational study.

SETTING

PICU (June 1, 2020 to May 31, 2021).

PATIENTS

Pediatric patients intubated and scheduled for extubation during the day shift in the PICU.

INTERVENTIONS

Multiple pre-extubation leak tests were performed on each patient immediately before extubation. In our center, the standard leak test is positive if a leak is audible at 30 cm H 2 O applied pressure with the MPTT cuff deflated. Two other tests were calculated in the pressure control-assist control ventilator mode using the following formulas: leak percentage with deflated cuff = (inspiratory tidal volume [V t ]-expiratory V t ) × 100/inspiratory V t ; cuff leak percentage = (expiratory V t with inflated cuff-expiratory V t with deflated cuff) × 100/expiratory V t with inflated cuff.

MEASUREMENTS AND MAIN RESULTS

The diagnostic criteria for PLE was made by at least two healthcare professionals and included upper airway stricture with stridor-requiring nebulized epinephrine. Eighty-five pediatric patients (< 15 yr) who had been intubated for at least 12 hours using the MPTT were included. Positive rates for the standard leak, leak percentage (cutoff 10%), and cuff leak percentage (cutoff 10%) tests were 0.27, 0.20, and 0.64, respectively. The standard leak, leak percentage, and cuff leak tests showed sensitivities of 0.36, 0.27, and 0.55, respectively; and specificities of 0.74, 0.81, and 0.35, respectively. PLE occurred in 11 of 85 patients (13%), and there were no instances of needing reintubation.

CONCLUSIONS

The pre-extubation leak tests in current practice for intubated pediatric patients in the PICU all lack diagnostic accuracy for PLE.

A view on pediatric airway management: a cross sectional survey study

BACKGROUND

This survey aimed to investigate routine practices and approaches of clinicians on pediatric airway in anesthesia and intensive care medicine.

METHODS

A 20-question multiple-choice questionnaire with the possibility to provide open text answers was developed and sent. The survey was sent to the members of European Airway Management Society via a web-based platform. Responses were analyzed thematically. Only the answers from one representative of the pediatric service of each hospital was included into the analysis.

RESULTS

Among the members, 143 physicians responded the survey, being anesthesiologists (83.2%), intensivists (11.9%), emergency medicine physicians (2.1%), and (2.8%) pain medicine practitioners. A straight blade was preferred by 115 participants (80.4%) in newborns, whereas in infants 86 (60.1%) indicated a curved blade and 55 (38.5%) a straight blade. Uncuffed tracheal tube were preferred by 115 participants (80.4%) in newborns, whereas 24 (16.8%) used cuffed tubes. Approximately 2/3 of the participants (89, 62.2%) reported not to use routinely a cuff manometer in their clinical practice, whereas 54 participants (37.8%) use it routinely in pediatric patients. Direct laryngoscopy for routine pediatric tracheal intubation was reported by 127 participants (88.8%), while 16 (11.2%) reported using videolaryngoscopes routinely. Interestingly, 39 (27.3%) had never performed neither videolaryngoscopy nor flexible bronchoscopy in children. These results were significantly less in hospitals with a dedicated pediatric anesthesiologist.

CONCLUSIONS

This survey on airway management in pediatric anesthesia revealed that the use of cuffed tubes and the routine monitoring of cuff pressure are rare. In addition, the rate of videolaryngoscopy or flexible optical intubation was low for expected difficult intubation. Our survey highlights the need for properly trained pediatric anesthesiologists working in-line with updated scientific evidence.

Airway Management in Pediatric Patients: Cuff-Solved Problem?

Traditionally, uncuffed tubes were used in pediatric patients under 8 years in pursuit of reducing the risk of postextubation stridor. Although computed tomography and magnetic resonance imaging studies confirmed that the subglottic area remains the narrowest part of pediatric airway, the use of uncuffed tubes failed to reduce the risk of subglottic swelling. Properly used cuffed tubes (correct size and correct cuff management) are currently recommended as the first option in emergency, anesthesiology and intensive care in all pediatric patients. Clinical practice particularly in the intensive care area remains variable. This review aims to analyze the current recommendation for airway management in children in emergency, anesthesiology and intensive care settings.

Ventilation Liberation Practices Among 380 International PICUs

1) Characterize the prevalence of ventilator liberation protocol use in international PICUs, 2) identify the most commonly used protocol elements, and 3) estimate an international extubation failure rate and use of postextubation noninvasive respiratory support modes.

Comparison of the success with two bending angles for lighted stylet intubation in children: A prospective randomised study

BACKGROUND AND AIM

The bend angle of a lighted stylet is an important factor for successful orotracheal intubation. The aim of this study was to test the differences in the success of endotracheal intubation using lighted stylet with 70° versus 90° bend angles in children aged 4-6 years with normal airways.

METHODS

A total of 136 children with normal airways required orotracheal intubation were enrolled and were randomly allocated to the 90° or 70° bend angle groups. The first-attempt success rate was assessed as the primary outcome. The intubation time, lighted stylet search time, lighted stylet withdrawal time, hemodynamic responses, and perioperative complications were recorded as secondary outcomes.

RESULTS

All intubations were completed within three attempts (the 90° group, 63/5/0; the 70° group, 55/11/2). The first-attempt success rate was higher in the 90° group than that in the 70° group (92.6% [63/68 patients] versus 80.9% [55/68 patients], respectively; risk ratio, 1.15; 95% CI, 1.01-1.31; p = .04). Esophageal entry occurred in nine of 83 intubation attempts in the 70° group and two of 73 intubation attempts in the 90° group (risk ratio, 1.09; 95% CI, 1.01-1.19; p = .04). The intubation time and the lighted stylet search time were significantly shorter in the 90° group than that in the 70° group (intubation time: 12.2 ± 2.0 s versus 14.9 ± 2.6 s, respectively; mean difference, 2.65; 95% CI, 1.87-3.43; p < .01; effect size, 1.16; lighted stylet search time: 5.4 ± 1.0 s versus 8.0 ± 1.6 s, respectively; mean difference, 2.66; 95% CI, 2.21-3.12; p < .01; effect size, 1.95).

CONCLUSIONS

Lighted stylet intubation with a 90° bend angle improved the first-attempt success rate and reduced esophageal intubation in children aged 4-6 years with normal airways.

Same baby, different care: variations in practice between neonatologists and pediatric intensivists

The aim of the study was to identify and explore areas in neonatal care in which significant differences in clinical care exist, among neonatal intensive care (NICU) and pediatric intensive care (PICU) physicians. A questionnaire presenting three common scenarios in neonatal critical care-severe pneumonia, post-cardiac-surgery care, and congenital diaphragmatic hernia (CDH) was electronically sent to all PICU and NICU physicians in Israel. The survey was completed by 110 physicians. Significant differences were noted between NICU and PICU physicians' treatment choices. A non-cuffed endotracheal tube, initial high-frequency ventilation, and lower tidal volumes when applying synchronized-intermittent-mechanical-ventilation were selected more often by NICU physicians. For sedation/analgesia, NICU physicians treated as needed or by continuous infusion of a single agent, while PICU physicians more often chose to continuously infuse ≥ 2 medications. Fentanyl, midazolam, and muscle relaxants were chosen more often by PICU physicians. Morphine administration was similar for both groups. Treating CDH with pulmonary hypertension and systemic hypotension, NICU physicians more often began treatment with high dose dopamine and/or dobutamine, while PICU physicians chose low-dose adrenalin and/or milrinone. For vascular access NICU physicians chose umbilical lines most often, while PICU physicians preferred other central sites.

CONCLUSION

Our study identified major differences in respiratory and hemodynamic care, sedation and analgesia, and vascular access between NICU and PICU physicians, resulting from field-specific consensus guidelines and practice traditions. We suggest to establish joint committees from both professions, aimed at finding the optimal treatment for this vulnerable population - be it in the NICU or in the PICU.

WHAT IS KNOWN

• Variability in neonatal care between the neonatal and the pediatric intensive care units has been previously described.

WHAT IS NEW

• This scenario-based survey study identified major differences in respiratory and hemodynamic care, sedation and analgesia, and vascular access between neonatologists and pediatric intensivists, resulting from lack of evidence-based literature to guide neonatal care, field-specific consensus guidelines, and practice traditions. • These findings indicate a need for joint committees, combining the unique skills and literature from both professions, to conduct clinical trials focusing on these specific areas of care, aimed at finding the optimal treatment for this vulnerable population - be it in the neonatal or the pediatric intensive care unit.

Impact of airway and a standardized recruitment maneuver on CT chest imaging quality in a pediatric population: A retrospective review

INTRODUCTION

When performing computerized tomography chest imaging in children, obtaining high quality, motion-free images is important in the accurate diagnosis of underlying pathology. General anesthesia is associated with the development of atelectasis, which can impair accurate diagnosis by obscuring or altering the appearance of the lung parenchyma or airways. Recruitment maneuvers, performed by anesthesiologists, can be used to effectively re-expand atelectatic lung.

METHODS

The computerized tomography chest imaging in 44 children aged between 2 months and 7 years, undergoing serial imaging for monitoring of cystic fibrosis, were reviewed and graded for atelectasis. The first scan performed on each child was performed with a supraglottic airway device and a non-standardized recruitment maneuver. The second scan on each child was performed with a cuffed endotracheal tube and a standardized recruitment maneuver.

RESULTS

When a supraglottic airway device and a non-standardized recruitment maneuver were used, 77% of patients demonstrated atelectasis of any degree on their computerized tomography chest imaging, compared with only 39% when a cuffed endotracheal tube and standardized recruitment maneuver were used. The percentage of computerized tomography chest scans that were scored acceptable (with either a total combined lung atelectasis score of 0 or 1) improved from 37% to 75% when a cuffed endotracheal tube and standardized recruitment maneuver were used. In particular, the mean atelectasis score for both lungs improved from 2.91 (SD ± 2.6) to 1.11 (SD ± 1.9), with a mean difference of 1.8 (95% CI 0.82-2.77; p: .0004).

CONCLUSION

The use of a cuffed endotracheal tube and a standardized recruitment maneuver is an effective way to reduce atelectasis as a result of general anesthesia. Anesthesiologists can actively contribute toward improved image quality through their choice of airway and recruitment maneuver.

Use of cuffed endotracheal tubes in infants less than 5 kilograms: A retrospective cohort study

BACKGROUND

Improved understanding of airway anatomy and refinement of equipment have led to the increased use of cuffed endotracheal tubes (ETTs) in infants and children. Despite expanded evidence on the potential advantages of cuffed ETTs in pediatric patients, there remains limited data on their use in infants less than 5 kilograms (kg). The current study retrospectively evaluates the perioperative use of cuffed ETTs in infants weighing 2-5 kg.

METHODS

This is a retrospective study from a tertiary care children's hospital involving a 3-year period. Data regarding anesthetic care, airway management, and postoperative course were retrospectively retrieved from the electronic medical record.

RESULTS

The study cohort included 1162 patients, 1086 of whom had their tracheas intubated with a cuffed ETT and 76 with an uncuffed ETT. Patients were divided into two groups for analysis: 2 to <3 kg and 3 to 5 kg. In both weight groups, cuffed ETTs resulted in a decreased need for more than one laryngoscopy and a change in ETT size with no increase in postoperative airway effects including stridor.

CONCLUSIONS

These data provide additional information regarding the efficacy and safety of cuffed ETTs in neonates and infants.

Aerosolized drug delivery in awake and anesthetized children to treat bronchospasm

Bronchospasm is a common respiratory adverse event in pediatric anesthesia. First-line treatment commonly includes inhaled salbutamol. This review focuses on the current best practice to deliver aerosolized medications to awake as well as anesthetized pediatric patients and discusses the advantages and disadvantages of various administration techniques. Additionally, we detail the differences between various airway devices used in anesthesia. We highlight the unmet need for innovation of orally inhaled drug products to deliver aerosolized medications during pediatric respiratory critical events such as bronchospasm. It is therefore important that clinicians remain up to date with the best clinical practice for aerosolized drug delivery in order to prevent and efficiently treat pediatric patients experiencing life-threatening respiratory emergencies.

Atelectasis and lung recruitment in pediatric anesthesia: An educational review

General anesthesia is associated with development of pulmonary atelectasis. Children are more vulnerable to the development and adverse effects of atelectasis. We review the physiology and risk factors for the development of atelectasis in pediatric patients under general anesthesia. We discuss the clinical significance of atelectasis, the use and value of recruitment maneuvers, and other techniques available to minimize lung collapse. This review demonstrates the value of a recruitment maneuver, maintaining positive end-expiratory pressure (PEEP) until extubation and lowering FiO₂ where possible in the daily practice of the pediatric anesthetist.

Anesthetic considerations in children with asthma

Due to the high prevalence of asthma and general airway reactivity, anesthesiologists frequently encounter children with asthma or asthma-like symptoms. This review focuses on the epidemiology, the underlying pathophysiology, and perioperative management of children with airway reactivity, including controlled and uncontrolled asthma. It spans from preoperative optimization to optimized intraoperative management, airway management, and ventilation strategies. There are three leading causes for bronchospasm (1) mechanical (eg, airway manipulation), (2) non-immunological anaphylaxis (anaphylactoid reaction), and (3) immunological anaphylaxis. Children with increased airway reactivity may benefit from a premedication with beta-2 agonists, non-invasive airway management, and deep removal of airway devices. While desflurane should be avoided in pediatric anesthesia due to an increased risk of bronchospasm, other volatile agents are potent bronchodilators. Propofol is superior in blunting airway reflexes and, therefore, well suited for anesthesia induction in children with increased airway reactivity.

Challenges with pediatric anesthesia and intraoperative ventilation of the child in the resource-constrained setting

The systemic challenges in providing safe anesthesia, including safe ventilation, to children in resource-constrained settings are many. For anesthesia providers caring for children, the lack of appropriate equipment, inadequate anesthesia workforce and deficiencies in postoperative care are especially difficult. The clinical decisions made by anesthesia providers around when and how to ventilate a child for surgery are influenced by all of these factors and can result in patient management which may vary significantly from that in a high-resource setting. This educational review considers the intraoperative ventilation of a small child in a resource-constrained setting and discusses specific challenges and context-sensitive solutions.

Risk assessment and optimization strategies to reduce perioperative respiratory adverse events in Pediatric Anesthesia-Part 2: Anesthesia-related risk and treatment options

Perioperative respiratory adverse events are the most common cause of critical events in children undergoing anesthesia and surgery. While many risk factors remain unmodifiable, there are numerous anesthetic management decisions which can impact the incidence and impact of these events, especially in at-risk children. Ongoing research continues to improve our understanding of both the influence of risk factors and the effect of specific interventions. This review discusses anesthesia risk factors and outlines strategies to reduce the rate and impact of perioperative respiratory adverse events with a chronologic based inquiry into anesthetic management decisions through the perioperative period from premedication to postoperative disposition.

Cuffed versus uncuffed endotracheal tubes for neonates

BACKGROUND

Endotracheal intubation is a commonly performed procedure in neonates, the risks of which are well-described. Some endotracheal tubes (ETT) are equipped with a cuff that can be inflated after insertion of the ETT in the airway to limit leak or aspiration. Cuffed ETTs have been shown in larger children and adults to reduce gas leak around the ETT, ETT exchange, accidental extubation, and exposure of healthcare workers to anesthetic gas during surgery. With improved understanding of neonatal airway anatomy and the widespread use of cuffed ETTs by anesthesiologists, the use of cuffed tubes is increasing in neonates.

OBJECTIVES

To assess the benefits and harms of cuffed ETTs (inflated or non-inflated) compared to uncuffed ETTs for respiratory support in neonates.

SEARCH METHODS

We searched CENTRAL, PubMed, and CINAHL on 20 August 2021; we also searched trial registers and checked reference lists to identify additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-RCTs, and cluster-randomized trials comparing cuffed (inflated and non-inflated) versus uncuffed ETTs in newborns. We sought to compare 1. inflated, cuffed versus uncuffed ETT; 2. non-inflated, cuffed versus uncuffed ETT; and 3. inflated, cuffed versus non-inflated, cuffed ETT.

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal. Two review authors independently assessed studies identified by the search strategy for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We identified one eligible RCT for inclusion that compared the use of cuffed (inflated if ETT leak greater than 20% with cuff pressure 20 cm H₂O or less) versus uncuffed ETT. The author provided a spreadsheet with individual data. Among 76 infants in the original manuscript, 69 met the inclusion and exclusion criteria for this Cochrane Review. We found possible bias due to lack of blinding and other bias. We are very uncertain about frequency of postextubation stridor, because the confidence intervals (CI) of the risk ratio (RR) were very wide (RR 1.36, 95% CI 0.35 to 5.25; risk difference (RD) 0.03, -0.11 to 0.18; 1 study, 69 participants; very low-certainty evidence). No neonate was diagnosed with postextubation subglottic stenosis; however, endoscopy was not available to confirm the clinical diagnosis. We are very uncertain about reintubation for stridor or subglottic stenosis because the CIs of the RR were very wide (RR 0.27, 95% CI 0.01 to 6.49; RD -0.03, 95% CI -0.11 to 0.05; 1 study, 69 participants; very low-certainty evidence). No neonate had surgical intervention (e.g. endoscopic balloon dilation, cricoid split, tracheostomy) for stridor or subglottic stenosis (1 study, 69 participants). Neonates randomized to cuffed ETT may be less likely to have a reintubation for any reason (RR 0.06, 95% CI 0.01 to 0.45; RD -0.39, 95% CI -0.57 to -0.21; number needed to treat for an additional beneficial outcome 3, 95% CI 2 to 5; 1 study, 69 participants; very low-certainty evidence). We are very uncertain about accidental extubation because the CIs of the RR were wide (RR 0.82, 95% CI 0.12 to 5.46; RD -0.01, 95% CI -0.12 to 0.10; 1 study, 69 participants; very low-certainty evidence). We are very uncertain about all-cause mortality during initial hospitalization because the CIs of the RR were extremely wide (RR 2.46, 95% CI 0.10 to 58.39; RD 0.03, 95% CI -0.05 to 0.10; 1 study, 69 participants; very low-certainty evidence). There is one ongoing trial. We classified two studies as awaiting classification because outcome data were not reported separately for newborns and older infants.

AUTHORS' CONCLUSIONS

Evidence for comparing cuffed versus uncuffed ETTs in neonates is limited by a small number of babies in a single RCT with possible bias. There is very low certainty evidence for all outcomes of this review. CIs of the estimate for postextubation stridor were wide. No neonate had clinical evidence for subglottic stenosis; however, endoscopy results were not available to assess the anatomy. Additional RCTs are necessary to evaluate the benefits and harms of cuffed ETTs (inflated and non-inflated) in the neonatal population. These studies must include neonates and be conducted both for short-term use (in the setting of the operating room) and chronic use (in the setting of chronic lung disease) of cuffed ETTs.

Incidence of Post-extubation Stridor in Infants With Cuffed vs. Uncuffed Endotracheal Tube: A Retrospective Cohort Analysis

BACKGROUND

Endotracheal intubation is a common procedure in Neonatal Intensive Care. While cuffed endotracheal tubes (ETT) are the standard of care in adults and children, their use in infants is controversial. The aim of this study was to compare the incidence of post-extubation stridor between uncuffed and cuffed ETTs in infants. We further evaluated the safety of cuffed ETTs in infants with a bodyweight between 2 and 3 kg and performed baseline analysis on development of subglottic stenosis.

METHODS

In this retrospective study, we screened all infants admitted to two NICUs of the Medical University of Vienna between 2012 and 2019.The study cohort was screened twice: In the first screening we selected all infants who underwent the first intubation when attaining a bodyweight >2 kg (but <6 kg) to analyze the incidence of post-extubation stridor and only considered the first intubation of each included infant. Post-extubation stridor was defined as the administration of either epinephrine aerosol or any corticosteroid within 6 h post-extubation. In the second screening we searched for all infants diagnosed with acquired severe subglottic stenosis during the study period regardless their bodyweight and numbers of intubations.

RESULTS

A total of 389 infants received at least one intubation during the study period. After excluding infants who underwent the first intubation below a bodyweight of 2 kg, 271 infants remained for final analysis with an average gestational age of 38.7 weeks at the time of intubation. Among those, 92 (33.9%) were intubated with a cuffed and 179 (66.1%) with an uncuffed ETT. Seven infants (2.6%) developed a clinically significant stridor: five of those were intubated with a cuffed and two with an uncuffed ETT (71.4 vs. 28.6%, p = 0.053). All of them had a bodyweight >3 kg at the time of intubation. Infants who developed subglottic stenosis were more often intubated with an uncuffed ETT.

CONCLUSION

In this study, no difference in the incidence of post-extubation stridor between cuffed and uncuffed ETTs in infants with a bodyweight from 2 to 6 kg could be found. The use of uncuffed ETTs does not exhibit higher risk for the acquired subglottic stenosis in this cohort.

Comparison of the efficacy and safety of cuffed versus uncuffed endotracheal tubes for infants in the intensive care setting: a pilot, unblinded RCT

OBJECTIVE

To study effectiveness and safety of cuffed versus uncuffed endotracheal tubes (ETTs) in small infants in the intensive care unit (ICU).

DESIGN

Pilot RCT.

SETTING

Neonatal and paediatric ICUs of children's hospital in Western Australia.

PARTICIPANTS

Seventy-six infants ≥35 weeks gestation and infants <3 months of age, ≥3 kg.

INTERVENTIONS

Patients randomly assigned to Microcuff cuffed or Portex uncuffed ETT.

MAIN OUTCOMES MEASURES

Primary outcome was achievement of optimal ETT leak in target range (10%-20%). Secondary outcomes included: reintubations, ventilatory parameters, ventilatory complications, postextubation complications and long-term follow-up.

RESULTS

Success rate (achievement of mean leak in the range 10%-20%) was 13/42 (30.9%) in the cuffed ETT group and 6/34 (17.6%) in uncuffed ETT group (OR=2.09; 95% CI (0.71 to 6.08); p=0.28). Mean percentage time within target leak range in cuffed ETT group 28% (IQR: 9-42) versus 15% (IQR: 0-28) in uncuffed ETT group (p=0.01). There were less reintubations to optimise size in cuffed ETT group 0/40 versus 10/36 (p<0.001). No differences were found in gaseous exchange, ventilator parameters or postextubation complications. There were fewer episodes of atelectasis in cuffed ETT group 0/42 versus 4/34 (p=0.03). No patient had been diagnosed with subglottic stenosis at long-term follow-up.

CONCLUSIONS

There was no difference in the primary outcome, though percentage time spent in optimal leak range was significantly higher in cuffed ETT group. Cuffed ETTs reduced reintubations to optimise ETT size and episodes of atelectasis. Cuffed ETTs may be a feasible alternative to uncuffed ETTs in this group of patients.

TRIAL REGISTRATION NUMBER

ACTRN12615000081516.

The prevalence of difficult airway and its associated factors in pediatric patients who underwent surgery under general anesthesia: An observational study

Background:

The airway of an anesthetized patient should be secured with an artificial airway for oxygenation or ventilation. Pediatrics are not small adults which means they are different from adults both anatomically and physiologically. This study aims to determine the prevalence of difficult airway and its associated factors in pediatric patients who underwent surgery under general anesthesia in referral hospitals of Addis Ababa.

Methods:

A multi-centered cross-sectional study design was employed. The bivariable and multivariable logistic regression was used to measure the association between the dependent variable (pediatrics difficult airway) and independent variables. p-value < 0.05 was used to declare statistical significance.

Results:

A total of 290 pediatrics patients were included in this study. The prevalence of difficult airway in pediatrics patients who underwent surgery was 19.7%. In multivariate logistic regression, pediatrics patients less than 2 years of age (adjusted odds ratio = 6.768, 95% confidence interval = 2.024, 22.636), underweight pediatrics patients (adjusted odds ratio = 4.661, 95% confidence interval = 1.196, 18.154), pediatrics patients having anticipated difficult airway (adjusted odds ratio = 18.563, 95% confidence interval = 4.837, 71.248), history of the difficult airway (adjusted odds ratio = 8.351, 95% confidence interval = 2.033, 34.302), the experience of anesthetists less than 4 years of age (adjusted odds ratio = 9.652, 95% confidence interval = 2.910, 32.050) had a significant association with pediatrics difficult airway.

Conclusion:

Being pediatric patients less than 2 years of age, underweight pediatrics patients, having anticipated difficult airway, those anesthetists who do not perform enough pediatric cases were identified as the main factors associated with the greater occurrence of difficult airway in pediatric patients.

Just Breathe: Tips and Highlights for Managing Pediatric Respiratory Distress and Failure

Anatomically, the airway is ever changing in size, anteroposterior alignment, and point of most narrow dimension. Special considerations regarding obesity, chronic and acute illness, underlying developmental abnormalities, and age can all affect preparation and intervention toward securing a definitive airway. Mechanical ventilation strategies should focus on limiting peak inspiratory pressures and optimizing lung protective tidal volumes. Emergency physicians should work toward minimizing risk of peri-intubation hypoxemia and arrest. With review of anatomic and physiologic principles in the setting of a practical approach toward evaluating and managing distress and failure, emergency physicians can successfully manage critical pediatric airway encounters.

[Ventilation in Pediatric Anesthesia]

About nine percent of all anesthesia procedures per year are performed in children. The risk for complications in pediatric anesthesia is higher in comparison with adults. There are significant differences in anatomy, physiology and pharmacology between pediatric and adult patients. Respiratory complications and circulations dysregulation occur more often in children. The most important consideration in the safe practice of pediatric anesthesia is to ensure a patent airway. Appropriate intraoperative management of newborns and infants needs a senior anesthetist with good knowledge and clinical experience including the management of possible complications.

Cuffed endotracheal tubes in neonates and infants of less than 3 kg body weight-A retrospective audit

BACKGROUND

Large prospective clinical studies have shown that modern cuffed pediatric tracheal tubes can be used safely, even in children weighing ≥3 kg. There is a growing interest in their use in children weighing <3 kg so that they, too, can benefit from the potential advantages, particularly the high probability of these tubes fitting into and sealing the pediatric airway at the first intubation attempt. This study aimed to find a cut-off body weight for procedures requiring a cuffed tracheal tube to seal the airway in children weighing <3 kg and to evaluate the frequency and predictive factors for the requirement to place a cuffed instead of an uncuffed tracheal tube.

METHODS

This study was a retrospective analysis of 269 children weighing 2000-2999 g, primarily intubated by pediatric anesthetists. Frequency of intubation with uncuffed Sheridan tubes versus cuffed Microcuff^® Pediatric Endotracheal Tube (PET) 3.0 mm ID was studied. Predictive variables were assessed by means of logistic regression analysis. The ROC curve for weight at intubation time and Youden index was calculated.

RESULTS

The 149 (55.4%) children were finally intubated with a cuffed tracheal tube. Logistic regression demonstrated that body weight at tracheal intubation and birth weight were the strongest predictors for the appropriateness of cuffed/uncuffed tracheal tubes. The threshold weight at tracheal intubation was 2700 g for a probability >50% of using a cuffed tracheal tube.

CONCLUSION

Half of the children weighing 2000-2999 g received a Microcuff^® PET 3.0 mm ID, especially those with a body weight above 2700 g. Because of the anatomical dimensions in patients with a body weight of 2000-2999 g, cuffed tracheal tubes with smaller outer diameters may be required to better fit their airways.

The Throat Pack Debate: A Review of Current Practice in UK and Ireland Cleft Centers

INTRODUCTION

The use of throat packs during oropharyngeal surgery has long been a topic of debate among cleft surgeons. The advantage of inserting an absorbent tulle within the pharynx must be weighed against the risk of unintended retention postoperatively. Despite safety check mechanisms in place, retention may occur with potentially life-threatening consequences. We present a comprehensive review of throat pack use in all cleft units within the United Kingdom and Ireland.

METHODS

All 20 cleft surgery units in the United Kingdom and Ireland were surveyed on their use of throat packs in children aged 6 months to 2 years undergoing elective cleft palate surgery.

RESULTS

The response rate to the survey was 100%. Seventy-five percent of units currently use throat packs; in 40%, they are used in addition to cuffed endotracheal tubes (ETTs). Inclusion of the throat pack in the surgical swab count was perceived as the safest mechanism employed to avoid retention. 26.1% of respondents were aware of at least 1 incident of pack retention in their unit.

DISCUSSION/CONCLUSION

The reported UK and Irish experience demonstrates that three-quarters of units routinely use packs. Notably, a quarter of respondents to the survey have experience of an incident of throat pack retention. Nevertheless, the majority of respondents considered the perceived risk of retaining a pack to be low. The growing use of microcuffed ETTs in UK cleft units paired with a low incidence of perioperative complications when a throat pack is not introduced might prompt cleft surgeons to review routine pharyngeal packing.

Frequency and characterization of the use of cuffed tracheal tubes in neonatal and pediatric intensive care units in Brazil

Objective

To identify the neonatal, pediatric and mixed (neonatal and pediatric) intensive care units in Brazil that use cuffed tracheal tubes in clinical practice and to describe the characteristics related to the use of protocols and monitoring.

Methods

To identify the intensive care units in Brazil, the Ministry of Health’s National Registry of Health Facilities was accessed, and information was collected on 693 registered intensive care units. This was an analytical cross-sectional survey conducted through electronic questionnaires sent to 298 neonatal, pediatric and mixed intensive care units in Brazil.

Results

This study analyzed 146 questionnaires (49.3% from neonatal intensive care units, 35.6% from pediatric intensive care units and 15.1% from mixed pediatric intensive care units). Most of the participating units (78/146) used cuffed tracheal tubes, with a predominance of use in pediatric intensive care units (52/78). Most of the units that used cuffed tracheal tubes applied a cuff pressure monitoring protocol (45/78). The use of cuff monitoring protocols was observed in intensive care units with a physical therapy service exclusive to the unit (38/61) and in those with a physical therapist present 24 hours/day (25/45). The most frequent cause of extubation failure related to the use of cuffed tracheal tubes in pediatric intensive care units was upper airway obstruction.

Conclusion

In this survey, the use of cuffed tracheal tubes and the application of a cuff pressure monitoring protocol was predominant in pediatric intensive care units. The use of a monitoring protocol was more common in intensive care units that had a physical therapist who was exclusive to the unit and was present 24 hours/day.

Uncuffed Endotracheal Tube Experience in Pediatric Patients with Laparotomy and Laparoscopic Surgeries

Aim

The aim of this study is to compare endotracheal tube leak, tube selection, mechanical ventilation, and side effects in the use of uncuffed tubes in both laparoscopic and laparotomy surgeries in pediatric patients. Material and Method. Patients who underwent laparotomy (LT group) or laparoscopic (LS group) surgery between 1 and 60 months. In the selection of uncuffed tubes, it was also planned to start endotracheal intubation with the largest uncuffed tube and to start intubation with a small uncuffed tube if the tube encounters resistance and does not pass. Mechanical parameters, endotracheal tube size, tube changes, and side effects are recorded.

Results

A total of 102 patients, 38 females and 64 males, with a mean age of 10.9 ± 8.1 months, body weight 7.1 ± 3.7 kg, and height 67 ± 15 cm, were included. 54 patients underwent laparoscopic surgery, and 48 patients underwent laparotomy. Tube exchange was performed in a total of 18 patients. In patients who underwent tube exchange, 11 patients were intubated with a smaller ETT number and others endotracheal intubation; when the MV parameters were TVe < 8 ml/kg and ETT leak > 20%, a larger uncuffed tube was used due to PIP 30 cmH₂O pressure. Patients with aspiration were not found in the LT and LS groups. There was no difference in the intergroup evaluation for postoperative side effects such as cough, laryngospasm, stridor, and aspiration.

Conclusion

There was no significant difference between the groups in terms of tube changes and side effects. So that we can start with the largest possible uncuffed tube to decrease ETT leak, both laparotomy and laparoscopic operations in children can be achieved with safe mechanical ventilation and target tidal volume.

Anesthesia for Major Surgery in the Neonate

Perioperative risk of morbidity and mortality for neonates is significantly higher than that for older children and adults. At particular risk are neonates born prematurely, neonates with major or severe congenital heart disease, and neonates with pulmonary hypertension. Presently no consensus exists regarding the safest anesthetic regimen for neonates. Regional anesthesia appears to be safe, but does not reduce the overall risk of postoperative apnea. Former preterm infants require postoperative observation for apnea. The anesthesiologist caring for the neonate for major surgery should be knowledgeable of the unique physiology of the neonate and maintain the highest level of vigilance throughout.

The development of the cricoid cartilage and its implications for the use of endotracheal tubes in the pediatric population

BACKGROUND

The rigid cricoid cartilage is functionally the narrowest portion of the larynx. There is some controversy over the shape of the pediatric cricoid cartilage in the transverse plane. It is important to understand the development of the cricoid cartilage so that endo-traceheal tubes can be used more safely.

AIM

To determine changes in the internal diameter and shape of the cricoid cartilage during development and explore the implications of those changes for the selection of ETT type and size for children.

METHODS

The cervical computed tomography scans were reviewed in patients aged 1-20 years. After performing the multiplanar reconstruction and correcting the slant, the transverse and anteroposterior internal diameters of the inlet and outlet of the cricoid cartilage were measured, respectively. The angle between the arch and the lamina of the cricoid cartilage in the middle sagittal plane was measured. The ratios of transverse to anteroposterior diameter for the inlet and outlet of the cricoid cartilage were calculated, respectively.

RESULTS

In females, the internal diameters of the cricoid cartilage increased linearly with age. In males, the internal diameters of the cricoid cartilage exhibited a growth spurt during adolescence. The transverse diameter of the inlet was the smallest diameter of the cricoid cartilage, and the predicting formula of the transverse diameter of the inlet for children aged 1-12 was 0.4 × age (year) + 5.1, R²  = .758. The angle between the arch and lamina of the cricoid cartilage and the ratios of transverse to anteroposterior diameter correlated weakly with age.

CONCLUSION

The transverse inner diameter of the inlet is the smallest diameter of the cricoid cartilage. The "funnel shape" of the cricoid cartilage remains unchanged during development. The outer diameter should be considered when selecting an endotracheal tube.

A multidisciplinary, video-based, curriculum for management of the intubated and surgical airway patient for a pediatric hospital in El Salvador

OBJECTIVE

Primary objective is to determine the rate of intubation with inappropriately sized endotracheal tubes (ETTs) in a pediatric intensive care unit (PICU) in El Salvador. Secondary objective is to determine effectiveness of a video-based curriculum to teach local providers on pediatric advanced airway management and surgical approach to patients requiring airway reconstruction.

METHODS

Data for 296 intubated pediatric patients was collected over a six month period in a 16-bed PICU in El Salvador. Results of a learning behavior assessment survey completed by local healthcare workers informed a curriculum to complement on-site education during annual surgical airway mission trips. The video-based curriculum addressed proper sizing and use of cuffed endotracheal tubes, care of the intubated child and perioperative considerations of the surgical airway patient. Providers completed pre and post-curriculum quizzes to measure knowledge acquisition.

RESULTS

Over 6-months, 281 patients were intubated. Sixty-three percent had improperly sized ETTs. Thirty-one percent had a failed or accidental extubation. All-cause mortality was 24%. One hundred and fifty-nine Salvadorian providers completed a learning behavior survey informing a video-based curriculum. Sixty-four providers completed the curriculum. Post-curriculum quiz scores increased by 18.7%. Surgeons, anesthesiologist, intensivists and speech pathologists demonstrated significant improvement (p < 0.05).

CONCLUSION

Nearly two-thirds of intubated patients in a PICU in El Salvador have improperly sized ETTs and one-third require reintubation following planned or accidental extubation. The development of this first of its kind video-based curriculum for critical care and surgical training regarding how to properly care for the intubated child is coupled with the development of a longitudinal database to record pediatric airway related morbidity and mortality in the largest pediatric hospital in El Salvador. This model and system can be used to track the reduction in airway related morbidity and mortality directly related to a systems based intervention both in El Salvador and then elsewhere.

Uncuffed Endotracheal Tubes: Not Appropriate for Pediatric Critical Care Transport

OBJECTIVE

The effect of using uncuffed endotracheal tubes in children during interfacility critical care transport has not yet been assessed. We hypothesized that many children with uncuffed endotracheal tubes experience complications leading to replacement with a cuffed tube after arrival at a tertiary pediatric care facility.

METHODS

We conducted a retrospective case review of all intubated patients transported by our dedicated pediatric critical care transport team to our pediatric intensive care unit over a 3-year period. The incidence of urgent reintubation was studied.

RESULTS

A total of 213 children were referred for transport with an endotracheal tube in place, with 55 of those with an uncuffed endotracheal tube (25.8% of all intubated patients). Of those with uncuffed tubes, 24 patients needed their tubes replaced on an urgent basis by the medical team because of issues with ineffective ventilation (43.6% of patients with uncuffed tubes or 11.3% of all intubated patients). No cuffed tubes required replacement.

CONCLUSION

Placing an uncuffed endotracheal tube in the critically ill child who is referred to tertiary pediatric care results in a significant number of these patients undergoing a repeat laryngoscopy, with all associated risks, to replace the uncuffed tube with a cuffed tube.

Work of breathing for cuffed and uncuffed pediatric endotracheal tubes in an in vitro lung model setting

BACKGROUND

Over the last decade, cuffed endotracheal tubes are increasingly used in pediatric anesthesia and also in pediatric intensive care. However, the smaller inner diameter of cuffed endotracheal tubes and, implicitly, the increased endotracheal tube resistance is still a matter of debate.

AIMS

This in vitro study investigated work of breathing and inspiratory airway pressures in cuffed and uncuffed endotracheal tubes and the impact of pressure support ventilation and automatic tube compensation.

METHODS

In 5 simulated neonatal and pediatric lung models, the Active Servo Lung 5000 and an intensive care ventilator were used to quantify the differences in work of breathing under spontaneous breathing (with and without pressure support ventilation and automatic tube compensation) between cuffed and uncuffed endotracheal tubes. Additionally, differences in inspiratory airway pressures, measured either proximal or distal of the endotracheal tube, between cuffed and uncuffed endotracheal tubes under mechanical ventilation were investigated.

RESULTS

Work of breathing was overall 10.27% [95% confidence interval 9.01-11.94] higher with cuffed than with uncuffed endotracheal tubes and was dramatically reduced by 34.19% [95% confidence interval 31.61-35.25] with the application of pressure support. Automatic tube compensation almost diminished work of breathing differences between the 2 endotracheal tube types in nearly all pediatric lung models. Peak inspiratory and mean airway pressures measured at the proximal endotracheal tube end revealed significantly higher values in cuffed than in uncuffed endotracheal tubes. However, these differences measured at the distal end of the endotracheal tube became minimal.

CONCLUSION

This in vitro study confirmed significant differences in work of breathing and inspiratory pressures between cuffed and uncuffed endotracheal tubes. Work of breathing, however, is almost neutralized by pressure support ventilation with automatic tube compensation and distal inspiratory airway pressures that, from a clinical perspective, are not significantly increased.

Using middle finger length to determine the internal diameter of uncuffed tracheal tubes in paediatrics

The selection of an appropriately-sized tracheal tube is of critical importance in paediatric patients to reduce both the risk of subglottic stenosis from a tracheal tube that is too large, and inadequate ventilation or poor end-tidal gas monitoring from a tracheal tube that is too small. Age formulae are widely used, but known to be unreliable, often resulting in a need to change the tracheal tube. Previous work has shown that the length of the middle finger and the internal diameter can both be used to guide depth of tracheal tube insertion. Therefore, we hypothesised that middle finger length may also be related to tube internal diameter. We enrolled children aged up to 12 years presenting to our institution for elective anaesthesia and measured the length of the middle finger on the palmar aspect of the hand. Anaesthetists chose the airway device they felt most appropriate for the procedure, and were unaware of the middle finger measurement. Of 160 patients who were enrolled, 108 were included in the final analysis. We found a linear relationship between uncuffed tracheal tube internal diameter and median middle finger length for each size of tracheal tube. Relationship between middle finger length and cuffed tracheal tube internal diameter was less clear. We propose that the formula: 'middle finger length (cm) (round up to nearest 0.5) = internal diameter of uncuffed tracheal tube (mm)' may be an improvement compared with age formulae for selecting uncuffed tracheal tubes in children, although this requires formal testing.