Laryngeal Mask Airway as an Appropriate Option in Pediatric Laparoscopic Inguinal Hernia Repair: A Systematic Review and Meta-Analysis

OBJECTIVE

To elucidate the safety and effectiveness of laryngeal mask airway (LMA) use in pediatric patients undergoing laparoscopic inguinal hernia repair.

METHODS

Studies were searched on the PubMed, EMBASE, and Cochrane Library databases. Only randomized controlled trials (RCTs) were included. Primary outcomes were major perioperative respiratory adverse events (PRAEs), namely laryngospasm, bronchospasm, desaturation, and aspiration. Secondary outcomes were minor PRAEs, anesthesia time, and recovery time. A meta-analysis was performed to calculate risk ratios (RR), weighted mean difference (WMD), and 95 % confidence intervals (CI) by using random effects models.

RESULTS

In total, 5 RCTs comprising 402 patients were included. Regarding major PRAEs, laryngospasm (RR: 0.43, 95 % CI: 0.12 to 1.47; p = 0.18), bronchospasm, and aspiration all demonstrated no difference between the laryngeal and endotracheal groups. Desaturation exhibited a trend, but this trend was not sufficiently supported with statistical evidence (p = 0.09). For minor PRAEs, fewer patients experienced incidence of cough after laryngeal mask use (RR: 0.27, 95 % CI: 0.11 to 0.67; p = 0.005). Other PRAE, namely hoarseness (p = 0.06), sore throat (RR: 1.88, 95 % CI: 0.76 to 4.66; p = 0.18), and stridor, did not differ between the 2 groups. Additionally, both anesthesia time (WMD: -6.88 min, 95 % CI: -11.88 to -1.89; p < 0.00001) and recovery time (WMD: -4.85 min, 95 % CI: -6.51 to -3.19; p < 0.00001) were shortened in the LMA group.

CONCLUSION

LMA used in pediatric laparoscopic inguinal hernia repair demonstrated no greater safety risks than endotracheal tube intubation did. Thus, anesthesiologists may shift from conventional endotracheal tube use to LMA use. Moreover, anesthesia and recovery times were shortened in the LMA group, which resulted in more efficient use of the operating room. Because of these benefits, LMA could be an appropriate option for pediatric patients undergoing laparoscopic inguinal hernia repair.

LEVEL OF EVIDENCE

Treatment Study, LEVEL III.

Bacteriology of endotracheal tube biofilms and antibiotic resistance: a systematic review

Bacteria commonly adhere to surfaces and produce polymeric material to encase the attached cells to form communities called biofilms. Within these biofilms, bacteria can appear to be many times more resistant to antibiotics or disinfectants. This systematic review explores the prevalence and microbial profile associated with biofilm production of bacteria isolated from endotracheal tubes and its associations with antimicrobial resistance. A comprehensive search was performed on databases PubMed, Embase, and Google Scholar for relevant articles published between 1st January 2000 and 31st December 2022. The relevant articles were exported to Mendeley Desktop 1.19.8 and screened by title and abstract, followed by full text screening based on the eligibility criteria of the study. Quality assessment of the studies was performed using the Newcastle-Ottawa Scale (NOS) customized for cross-sectional studies. Furthermore, the prevalence of antimicrobial resistance in biofilm-producers isolated from endotracheal tube specimens was investigated. Twenty studies encompassing 981 endotracheal tubes met the eligibility criteria. Pseudomonas spp. and Acinetobacter spp. were predominant isolates among the biofilm producers. These biofilms provided strong resistance against commonly used antibiotics. The highest resistance rate observed in Pseudomonas spp. was against fluoroquinolones whereas the least resistance was seen against piperacillin-tazobactam. A similar trend of susceptibility was observed in Acinetobacter spp. with a very high resistance rate against fluoroquinolones, third-generation cephalosporins and carbapenems. In conclusion, endotracheal tubes were associated with colonization by biofilm forming bacteria with varying levels of antimicrobial resistance. Biofilms may promote the occurrence of recalcitrant infections in endotracheal tubes which need to be managed with appropriate protocols and antimicrobial stewardship. Research focus should shift towards meticulous exploration of biofilm-associated infections to improve detection and management.

Effect of a self-developed fixation device on preventing endotracheal intubation-related pressure injury: a randomised controlled trial

OBJECTIVE

To evaluate the effects of our self-developed endotracheal tube fixation device in mechanically ventilated patients.

METHODS

In a dual-centre randomised controlled trial, patients who were expected to require mechanical ventilation for over 48 h were assigned to the observation group (using self-developed device) or the control group (using the traditional device). The primary endpoint was the incidence of endotracheal intubation-related pressure injury (EIRPI).

RESULTS

Fifty-one patients in the observation group and 54 patients in the control group were analysed. The incidence of EIRPI was 7.8% in the observation group and 33.3% in the control group (p = 0.001). Lip pressure injury (PI) occurred in 0 versus 14 (25.9%) patients in the observation versus control groups (p < 0.001). Both oral-mucosal and facial PIs were similar between the two groups.

CONCLUSIONS

The use of the novel device reduced the incidence of EIRPI, especially lip PI. Trial registration Chinese Clinical Trial Registry ChiCTR2300078132. Registered on 29 November 2023.

Soft tissue injury events associated with neural integrity monitoring endotracheal tubes: A MAUDE database analysis

OBJECTIVE

Neural integrity monitoring (NIM) endotracheal tubes are widely used to provide intraoperative monitoring of the recurrent laryngeal nerve during certain neck surgeries, especially thyroidectomy, in order to reduce the risk of nerve injury and subsequent vocal fold paralysis. The unique design of NIM tubes and the increased technical skill required for correct placement compared to standard endotracheal tubes may increase the risk of upper aerodigestive tract soft tissue injury. This study aims to describe adverse events related to NIM endotracheal tubes.

STUDY DESIGN

Retrospective cross-sectional study.

SETTING

The US Food and Drug Administration's MAUDE database (2010-2022); (Manufacturer and User Facility Device Experience).

METHODS

The MAUDE database was queried for reports of adverse events that resulted in patient soft tissue injury involving the use of endotracheal tubes approved by the Food and Drug Administration.

RESULTS

There were 28 reported soft tissue injuries, with all events being related to the NIM EMG family of endotracheal tubes manufactured by Medtronic Xomed, Inc. Overall, 24 were categorized as device-related adverse events, and 4 were unspecified in the event description. The most common soft tissue injuries were edema (n = 7) and perforation (n = 7), each accounting for 25 % of adverse events. The second most common injury type was laceration (n = 4), representing 14 % of all adverse events. Overall, 9 patients (32 %) in our cohort required a surgical intervention to treat their injuries, which consisted of 6 tracheotomies and 3 instances of suture repair.

CONCLUSIONS

The most commonly reported types of soft tissue injury included edema and perforation, followed by laceration. Increased awareness of device-related patient injuries associated with NIM endotracheal tubes can be used to better inform surgeons and anesthesiologists during the process of intubation and surgical decision-making.

Biocompatibility and sub-chronic toxicity studies of phlorotannin/polycaprolactone coated trachea tube for advancing medical device applications

The phlorotannin-polycaprolactone-coated endotracheal tube (PP tube) has been developed with the aim of preventing tracheal stenosis that can result from endotracheal intubation, a factor that can lead to a serious airway obstruction. Its preventive efficacy has been assessed through both in vitro and in vivo investigations. However, there is a lack of studies concerning its biocompatibility and sub-chronic toxicity in animal models, a crucial factor to ensure the safety of its usage as a functional endotracheal tube. Thus, this study aimed to evaluate the biocompatibility and sub-chronic (13 weeks) toxicity of the PP tube through L929 cell line and diverse in vivo models. The cytotoxicity testing was performed using the extracts of PP tube on L929 cells for 72 h. Furthermore, other tests conducted on animal models, including ICR mice (acute systemic toxicity), New Zealand white rabbit (intradermal reactivity and pyrogen tests), guinea pig (maximization sensitization), and Sprague Dawley rats (sub-chronic toxicity). In both biocompatibility and sub-chronic toxicity analyses, no significant adverse effects are observed in the groups exposed to the PP tube, when compared to control group. Altogether, the findings suggested that the PP tube exhibits relative non-toxic and safety, supporting its suitability for clinical usage. However, extended periods of intubation may produce mild irritant responses, highlighting the clinical caution of limiting intubation duration to less than 13 weeks.

New Formula for Depth of Insertion of Endotracheal Tube in Children: A Prospective Observational Study

OBJECTIVES

To assess the correct placement of endotracheal tube (ETT) by confirming it with a flexible fiberoptic bronchoscope (FOB), to propose a new formula that would be suitable for Indian children, and to assess the movement of the ETT tip during neck flexion and extension.

METHODS

A total of 76 patients were included in the study between the age of 2 and 10 y. Depth of ETT insertion was assessed using FOB. ETT migration due to changes in head and neck position was also assessed.

RESULTS

It was observed that 6 out of 76 children had endobronchial/at carina position of ETT after the initial insertion as per the black line guidance in the neutral position. While the incidence was 23, 36, and 36, respectively as per Cole, weight-, and height-based formula.

CONCLUSION

The existing formulae are not suitable for Indian children as their physical stature is different from other ethnic populations. Therefore, the authors suggest a new formula [(Age/2) + 10 cm] for depth of ETT insertion for children of the authors' geographical area.

TRIAL REGISTRATION

CTRI/2015/06/005871.

Role of ultrasonography in upper airway assessment: A comparison with computerized tomography measurements

INTRODUCTION

This study aimed to compare ultrasonography (US) measurements of the upper airway to computerized tomography (CT) measurements. Our study's primary outcome is to research the accuracy of US measurements in the evaluation of upper airway diameters when CT is taken as the gold standard; the secondary outcome is to determine the time required to obtain US measurements.

METHODS

This prospective study included patients ≥18 years old that had undergone thoracic or neck CT due to current clinical necessity. The US measurement for each patient was performed by two researchers with different levels of experience, both of whom were blinded to each other and the CT measurements. Measurements were obtained from the vocal cords and subglottic region. The duration of the US performance was also recorded.

RESULTS

The US and CT measurements were obtained from 94 patients. Concordance between US and CT measurements was found in the Bland-Altman analysis, with a mean -0.05 mm difference for vocal cord diameter and -1.2 mm for subglottic diameter. The intra-class correlation coefficients (ICC) between the CT and US measurements were 0.993, and 0.609 for vocal cord and subglottic diameter measurements, respectively. The ICC between US performers was 0.992 for vocal cord diameter and 0.959 for subglottic diameter. The US's mean time for vocal cord diameter measurement was 38 ± 23 s, and the mean time for subglottic diameter measurement was 49 ± 30 s.

CONCLUSION

The concordance between US and CT measurements is high and the measurements of different practitioners with different experience levels are compatible with each other.

Effectiveness of substantial shortening of the endotracheal tube for decreasing airway resistance and increasing tidal volume during pressure-controlled ventilation in pediatric patients: a prospective observational study

The endotracheal tubes (ETTs) used for children have a smaller inner diameter. Accordingly, the resistance across ETT (RETT) is higher. Theoretically, shortening the ETTs can decrease total airway resistance (Rtotal), because Rtotal is sum of RETT and patient's airway resistance. However, the effectiveness of ETT shortening for mechanical ventilation in the clinical setting has not been reported. We assessed the effectiveness of shortening a cuffed ETT for decreasing Rtotal, and increasing tidal volume (TV), and estimated the RETT/Rtotal ratio in children. In anesthetized children in a constant pressure-controlled ventilation setting, Rtotal and TV were measured with a pneumotachometer before and after shortening a cuffed ETT. In a laboratory experiment, the pressure gradient across the original length, shortened length, and the slip joint alone of the ETT were measured. We then determined the RETT/Rtotal ratio using the above results. The clinical study included 22 children. The median ETT percent shortening was 21.7%. Median Rtotal was decreased from 26 to 24 cmH2O/L/s, and median TV was increased by 6% after ETT shortening. The laboratory experiment showed that ETT length and the pressure gradient across ETT are linearly related under a certain flow rate, and approximately 40% of the pressure gradient across the ETT at its original length was generated by the slip joint. Median RETT/Rtotal ratio were calculated as 0.69. The effectiveness of ETT shortening on Rtotal and TV was very limited, because the resistance of the slip joint was very large.

The impact of endotracheal intubation on oxygen delivery, trachea pressure and wall deformation

This paper concerns improving endotracheal tube (ETT) insertion through advanced computational science modelling. The study aims to better understand endotracheal intubation (ETI) and reduce medical errors in intensive and critical care units since ETT insertion is unique for each patient, depending on age, gender, size, physiology, and underlying health conditions. We have employed computational fluid dynamics and biomechanics modelling to investigate the effect of ETT for three ventilation modes on (a) local oxygen delivery to the lungs, (b) air pressure and wall shear stress at the tracheal walls, and (c) oscillatory elastic deformation of the tracheal tissues and muscle. For the first time, we reveal how the ventilation mode and ETT insertion in the trachea may induce major complications, especially in long periods of ETT. We show that rotating the ETT or displacing it by 2 mm only can induce a significant rise in the tracheal pressure up to 177 cmH2O. This study, for the first time, shows the vital role of computers in biology and medicine to provide enhanced decision-making-support to clinicians and medical doctors dealing with ETI.

Using a shortened uncuffed endotracheal tube as a nasopharyngeal airway: a useful adjunct during fiberoptic intubation training among anesthesia residents

Background

Fiberoptic intubation (FOI) is considered a beneficial modality used to intubate life-threatening airway patients. This study aims at assessing the effectiveness of shortened uncuffed endotracheal tube as a nasopharyngeal airway during FOI.

Methods

Between January 2019 and March 2021, this prospective randomized controlled trial has enrolled 62 adult patients (56 males and 6 females) with normal airways scheduled for elective oral FOI classified American Society of Anesthesiologists (ASA I-III), their age ranged 20-60 years. The patients were randomized into two equal groups (31 per each); in group I, FOI was carried using lingual traction, and in group II, FOI was carried out with lingual traction plus a shortened uncuffed endotracheal tube as a modified nasopharyngeal airway to maintain oxygenation. The time taken to successful tracheal intubation and other technical parameters have been measured. The heart rate (HR), mean arterial pressure (MAP), oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and any associated complications have been measured.

Results

During insertion of the scope, the SpO2 was significantly decreased in group I (92.55 ± 7.94) compared to group II (97.42 ± 6.34), p=0.009. The heart rate, MAP, and EtCO2 were found to be insignificantly different in both groups (p>0.05). The time needed for intubation in group I (2.78±0.98 min) was prolonged compared with group II (1.95±1.02 min) p =0.002. The number of attempts was comparable in both groups, while the number of successful intubations from the 1st attempt was 12 (39%) compared to 18 (58%) in groups I and II respectively, p=0.36. The overall success rate by juniors was 71% in group I compared to 84% in group II, p=0.66 with a lower incidence of using rescue oxygen and other facilitating maneuvers.

Conclusions

The modified nasopharyngeal airway is a useful modality to facilitate oral FOI by anesthesia resident trainees.

Response to letter for critiques on our published article: Effect of tracheal tube cuff inflation with alkalinized lidocaine versus air on hemodynamic responses during extubation and post-operative airway morbidities in children: prospective observational cohort study, Ethiopia

Endotracheal tube with an inflated cuff was used to manage and maintain the airway during general anesthesia in children. When the lateral pressure exerted by an inflated Endotracheal tube cuff on tracheal mucosa exceeds capillary perfusion pressure, patients may complain of cough, sore throat, and hoarseness in the postoperative period.

A Randomized Controlled Trial: Examining the Impact of the Novel Double Setup Endotracheal Tube on the Success Rates of Awake Fiber-Optic Orotracheal Intubation

BACKGROUND

Advancing the endotracheal tube (ETT) over a flexible bronchoscope (FB) during awake fiber-optic intubation (AFOI) is often impeded. Various maneuvers and tracheal tubes designed to overcome this obstruction may also be unsuccessful or costly.

OBJECTIVE

The current study aimed to assess how the novel double configuration ETT affected AFOI success rates on the first attempt.

METHODS

A randomized controlled experiment including 40 individuals receiving awake fiber-optic orotracheal intubation was performed in a 1:1 ratio with a single ETT railroaded with its bevel posteriorly (ST) or railroading with a double setup ETT (DT) over a flexible videoscope (FVS) for tracheal intubation. The number of intubation attempts, time spent intubating, and adverse events were examined and compared between the two groups.

RESULTS

Twenty patients received a single ETT railroaded with the bevel posteriorly, and 20 patients received railroading with the double setup ETT during AFOI. Intubation on the first attempt was significantly greater in the DT group (90%) than in the ST group (35%). The intubation time was considerably shorter for the DT group (12.8 [7.8-16.9] s) when compared with the ST group (27.9 [16.3-91.0] s). Five patients were intubated by the alternative technique after failure to intubate for several attempts, and 3 cases were found to have a crease in the FVS after intubation in group ST. During topical anesthetic, three individuals in each group experienced transient oxygen desaturation.

CONCLUSIONS

Our study discovered that the novel double setup tube could significantly improve the intubation success rate on the first attempt during AFOI for patients with challenging airway when a strategy based on a reduced gap between ETT and FB could not be applied.

Retrospective comparison of the effects of laryngeal mask and endotracheal tube on some cardio-respiratory variables in pet rabbits undergoing anaesthesia for elective gonadectomy

BACKGROUND

Endotracheal intubation in rabbits is challenging and supraglottic airway devices, such as laryngeal masks (LMA), represent an alternative as they are easy to insert, and do not stimulate the larynx requiring therefore a lighter plane of anaesthesia for their insertion and positioning than the endotracheal tubes. We investigated whether, compared to an endotracheal tube, the LMA can reduce the negative effects of general anaesthetics on some cardiovascular and respiratory parameters routinely monitored in rabbits anaesthetized for elective gonadectomy. The records of 21 adult mixed breed pet rabbits were collected retrospectively. Rabbits were divided in two groups based on the type of airway device used. A laryngeal mask secured the airway in group LMA (n = 11), and in group ETT (n = 10) an endotracheal tube was used. The amount of propofol used before successful insertion of the airway device was recorded. A pitot-based spirometer was connected and ventilatory variables were measured immediately after insertion. Pulse rate, non-invasive arterial blood pressure, haemoglobin oxygen saturation, respiratory rate, end-tidal carbon dioxide and volatile anaesthetic consumption were also monitored during the surgical procedure; extubation time was noted as well.

RESULTS

The use of LMA required significantly less propofol (0.8 to 4 mg/kg) for insertion than the ETT (1.2 to 5.6 mg/kg), and the difference was statistically significant (P < 0.01). No differences were observed in ventilatory variables measured immediately after airway positioning. Intraoperatively, there were no differences between groups for respiratory and cardiovascular variables, and amount of isoflurane administered. In all rabbits mean and diastolic blood pressure progressively decreased during surgery. Mean extubation time was shorter in group LMA (6 ± 2 min) than group ETT (8 ± 3 min, P < 0.01).

CONCLUSION

The airway device did not clinically affect the cardiovascular and respiratory variables during anaesthesia. Intraoperative hypoventilation was observed in most rabbits regardless of the device being used; therefore ventilatory support may be required. Rabbits with the laryngeal masks were extubated earlier.

Antimicrobial materials for endotracheal tubes: A review on the last two decades of technological progress

Ventilator-associated pneumonia (VAP) is an unresolved problem in nosocomial settings, remaining consistently associated with a lack of treatment, high mortality, and prolonged hospital stay. The endotracheal tube (ETT) is the major culprit for VAP development owing to its early surface microbial colonization and biofilm formation by multiple pathogens, both critical events for VAP pathogenesis and relapses. To combat this matter, gradual research on antimicrobial ETT surface coating/modification approaches has been made. This review provides an overview of the relevance and implications of the ETT bioburden for VAP pathogenesis and how technological research on antimicrobial materials for ETTs has evolved. Firstly, certain main VAP attributes (definition/categorization; outcomes; economic impact) were outlined, highlighting the issues in defining/diagnosing VAP that often difficult VAP early- and late-onset differentiation, and that generate misinterpretations in VAP surveillance and discrepant outcomes. The central role of the ETT microbial colonization and subsequent biofilm formation as fundamental contributors to VAP pathogenesis was then underscored, in parallel with the uncovering of the polymicrobial ecosystem of VAP-related infections. Secondly, the latest technological developments (reported since 2002) on materials able to endow the ETT surface with active antimicrobial and/or passive antifouling properties were annotated, being further subject to critical scrutiny concerning their potentialities and/or constraints in reducing ETT bioburden and the risk of VAP while retaining/improving the safety of use. Taking those gaps/challenges into consideration, we discussed potential avenues that may assist upcoming advances in the field to tackle VAP rampant rates and improve patient care. STATEMENT OF SIGNIFICANCE: The use of the endotracheal tube (ETT) in patients requiring mechanical ventilation is associated with the development of ventilator-associated pneumonia (VAP). Its rapid surface colonization and biofilm formation are critical events for VAP pathogenesis and relapses. This review provides a comprehensive overview on the relevance/implications of the ETT biofilm in VAP, and on how research on antimicrobial ETT surface coating/modification technology has evolved over the last two decades. Despite significant technological advances, the limited number of gathered reports (46), highlights difficulty in overcoming certain hurdles associated with VAP (e.g., persistent colonization/biofilm formation; mechanical ventilation duration; hospital length of stay; VAP occurrence), which makes this an evolving, complex, and challenging matter. Challenges and opportunities in the field are discussed.

Biogenic nanosilver-fabricated endotracheal tube to prevent microbial colonization in a veterinary hospital

COVID-19 patients have often required prolonged endotracheal intubation, increasing the risk of developing ventilator-associated pneumonia (VAP). A preventive strategy is proposed based on an endotracheal tube (ETT) modified by the in situ deposition of eucalyptus-mediated synthesized silver nanoparticles (AgNPs). The surfaces of the modified ETT were embedded with AgNPs of approximately 28 nm and presented a nanoscale roughness. Energy dispersive X-ray spectroscopy confirmed the presence of silver on and inside the coated ETT, which exhibited excellent antimicrobial activity against Gram-positive and Gram-negative bacteria, and fungi, including multidrug-resistant clinical isolates. Inhibition of planktonic growth and microbial adhesion ranged from 99 to 99.999% without cytotoxic effects on mammalian cells. Kinetic studies showed that microbial adhesion to the coated surface was inhibited within 2 h. Cell viability in biofilms supplemented with human tracheal mucus was reduced by up to 95%. In a porcine VAP model, the AgNPs-coated ETT prevented adhesion of Pseudomonas aeruginosa and completely inhibited bacterial invasion of lung tissue. The potential antimicrobial efficacy and safety of the coated ETT were established in a randomized control trial involving 47 veterinary patients. The microbial burden was significantly lower on the surface of the AgNPs-coated ETT than on the uncoated ETT (p < 0.05). KEY POINTS: • Endotracheal tube surfaces were modified by coating with green-synthesized AgNPs • P. aeruginosa burden of endotracheal tube and lung was reduced in a porcine model • Effective antimicrobial activity and safety was demonstrated in a clinical trial.

Mist nebulizer versus heated humidifier on endotracheal tube patency in spontaneously breathing intubated patients: A prospective, randomized controlled trial

Background and Aims

Using a humidifier in intubated patients is now a standard of care as the humidifying effect of the upper airway is lost. We conducted this study to compare the efficacy of a heated humidifier (HH) with the more commonly used conventional mist nebulizer on overnight intubated and spontaneously breathing post-operative patients.

Material and Methods

This prospective, randomized control trial included 60 post-operative overnight intubated and spontaneously breathing patients, of which 30 patients were allocated to the HH group and 30 to the mist nebulizer group. The reduction of endotracheal tube (ETT) patency was measured quantitatively by the difference between the pre-intubation and immediate post-extubation ETT volume and compared between the two groups. Also, the characteristics of secretion, the temperature of inspired gas at the Y-piece, and the frequency of refilling the humidifier chamber were recorded and compared.

Results

The reduction of ETT volume was significantly more in the mist nebulizer group compared to the HH group (P-value 0.00026). The mean temperature of the inspired gas (°C) was higher in the HH group (P-value < 0.0001). More patients in the mist nebulizer group had thicker (P-value 0.057) and drier secretions (P-value 0.005) compared to the HH group. None of the patients in the HH group required refilling of the humidifier chamber while the mean frequency of the refilling was 3.5 times per patient in the mist nebulizer group.

Conclusion

HH may be preferred over mist nebulizer as the latter requires more frequent refilling which may not be practically possible in a busy recovery room rendering the patient at the risk of inhaling dry gas and consequent thick and dry secretions with decreased ETT patency.

AIRWAY MANAGEMENT IN LAPAROSCOPIC CHOLECYSTECTOMY - A COMPARATIVE ANALYSIS

In this study, we aimed to compare supraglottic airway devices (Supreme and i-gel laryngeal mask) with tracheal tube with respect to airway control and efficiency in ventilation and oxygenation. The study included 325 patients of ASA I-II who underwent laparoscopic cholecystectomy. In group 1, the airway was secured using endotracheal intubation (115 patients). In group 2 (103 patients), LMA Supreme was applied, whereas i-gel mask was used for airway management in group 3 (107 patients). Monitoring parameters were recorded and compared using t-test, analysis of variance (ANOVA), Tukey's test and χ2-test. The following parameters were monitored: insertion time, number of attempts for device placement, oropharyngeal seal pressure, etc. Insertion time was longest in group 1 (14.7±1.65 s) as compared to group 2 (15.5±1.05 s) and group 3 (14.1±1.27 s); ANOVA test yielded a statistically significant difference (p<0.01). Insertion success rate was almost identical in all three groups (p=0.907, χ2-test). Comparison of oropharyngeal seal pressure between group 2 (35.95±2.92 cm H2O) and group 3 (36.47±1.43 cm H2O) yielded no statistical difference (p=0.314, t-test). Endotracheal tube, Supreme and i-gel laryngeal masks were shown to be equally efficient in airway management in laparoscopic cholecystectomy. All three devices enabled efficient ventilation and oxygenation despite certain pathophysiological changes associated with laparoscopy.

COMPARISON OF FLEXIBLE LARYNGEAL MASK INSERTION AND ENDOTRACHEAL INTUBATION IN ADENOTONSILLECTOMY SURGERY

This study compared the effectiveness of flexible laryngeal mask (F-LMA) insertion and endotracheal intubation in pediatric patients undergoing adenotonsillectomy surgery. A total of 60 patients aged 2-12 years were included in the study. Patients were divided into the F-LMA group (n=30) and endotracheal tube (ETT) group (n=30). The groups were compared according to intubation time, heart rate, SpO2, EtCO2, airway pressure, surgical field of view, and recovery time. Both the insertion time and recovery time were shorter in the F-LMA group than in the ETT group (16.93±4.84 s vs. 23.93±8.74 s; and 10±2 min vs. 14.5±3 min; p<0.001 both). The airway pressure measurements at 5-min intervals were significantly lower in the F-LMA group than in the ETT group (p<0.001). F-LMA may be a useful alternative to ETT for adenotonsillectomy surgery because it is safe, provides shorter induction and recovery times, reduces intraoperative airway pressure, and provides an adequate operative field of view.

Pressure changes in tapered and cylindrical shaped cuff after extension of head and neck: A randomized controlled trial

BACKGROUND

The proper cuff pressure of endotracheal tube (ET) plays an important role in sealing the airway and preventing airway complications during mechanical ventilation. The ET cuff shape affects the cuff pressure after positional change.

AIM

To investigate cuff pressure between tapered and cylindrical cuff after extension of head and neck during nasal endotracheal intubation.

METHODS

In a randomized clinical trial, 52 patients were randomized to one of two groups: cylindrical cuff or Tapered cuff. Cuff pressure with 22 cmH₂O was applied to patients in the neutral position. After extension of head and neck, the cuff pressure was evaluated again and readjusted to 22 cmH₂O. In addition, the extent of cephalad migration of ET tip was assessed and postoperative airway complications such as sore throat, and hoarseness were measured.

RESULTS

The cuff pressure was higher in the tapered cuff (28.7 ± 1.0 cmH₂O) than in the cylindrical cuff (25.5 ± 0.8 cmH₂O) after head and neck extension (P < 0.001). The extent of cephalad migration of tube tip was greater in TaperGuard ET (18.4 ± 2.2 mm) than in conventional ET (15.1 ± 1.2 mm) (P < 0.001). The incidence of postoperative airway complications was comparable between two groups.

CONCLUSION

After head and neck extension, the cuff pressure and the extent of cephalad migration of ET was greater in tapered cuff than in cylindrical cuff during nasal intubation, respectively.

Durability and disinfection of single-use endotracheal tubes following exposure to commonly available medical disinfecting compounds

BACKGROUND

Reusing single-use medical supplies offers a capability enhancement during massive casualty incidents when resupply of medical supplies is unavailable in times of national health care crises. This pilot study determined the feasibility of disinfection of endotracheal tubes with commonly used chemical disinfecting agents.

METHODS

Endotracheal tubes (ETTs) were subjected to either CaviCide, Neutral Disinfectant Cleaner, Cidex, or saline according to the manufacturer's recommended disinfection contact times. Alterations to the polyvinyl chloride (PVC) integrity by disinfecting agents were determined by volume/pressure measurements within the ETT cuff. To test the disinfection rate, ETTs were inoculated with Staphylococcus Aureus and subjected to experimental disinfection protocol.

FINDINGS

There were no significant alterations to ETT tracheal cuff function and mixed results in disinfection among ETTs. ETTs bacterial culture data presented possible contamination among the groups.

DISCUSSION

These data support the feasibility of single-use ETT reuse as a last resort while making every attempt and effort to follow established protocols to minimize harm to the patient.

A comparison of endotracheal tube compensation techniques for the measurement of respiratory mechanical impedance at low frequencies

Measurement of respiratory impedance ([Formula: see text]) in intubated patients requires accurate compensation for pressure losses across the endotracheal tube (ETT). In this study, we compared time-domain (TD), frequency-domain (FD) and combined time-/frequency-domain (FT) methods for ETT compensation. We measured total impedance ([Formula: see text]) of a test lung in series with three different ETT sizes, as well as in three intubated porcine subjects. Pressure measurement at the distal end of the ETT was used to determine the true [Formula: see text]. For TD compensation, pressure distal to the ETT was obtained based on its resistive and inertial properties, and the corresponding [Formula: see text] was estimated. For FD compensation, impedance of the isolated ETT was obtained from oscillatory flow and pressure waveforms, and then subtracted from [Formula: see text]. For TF compensation, the nonlinear resistive properties of the ETT were subtracted from the proximal pressure measurement, from which the linear resistive and inertial ETT properties were removed in the frequency-domain to obtain [Formula: see text]. The relative root mean square error between the actual and estimated [Formula: see text] ([Formula: see text]) showed that TD compensation yielded the least accurate estimates of [Formula: see text] for the in vitro experiments, with small deviations observed at higher frequencies. The FD and TF compensations yielded estimates of [Formula: see text] with similar accuracies. For the porcine subjects, no significant differences were observed in [Formula: see text] across compensation methods. FD and TF compensation of the ETT may allow for accurate oscillometric estimates of [Formula: see text] in intubated subjects, while avoiding the difficulties associated with direct tracheal pressure measurement.

Recall of extubation after remimazolam anesthesia with flumazenil antagonism during emergence: a retrospective clinical study

PURPOSE

This study was performed to examine and compare the incidence of extubation recall in surgical patients who underwent remimazolam anesthesia with flumazenil antagonism during emergence and in those who underwent propofol anesthesia.

METHODS

One hundred sixty-three patients who underwent surgery using general endotracheal or supraglottic airway anesthesia with propofol (n = 97) or remimazolam (n = 66) were retrospectively analyzed. Remimazolam was antagonized by flumazenil after discontinuation of remimazolam at the end of surgery. The endotracheal tube or supraglottic airway was removed after surgery was complete, and consciousness and adequate spontaneous breathing were confirmed. The incidence of extubation recall was compared between the remimazolam and propofol anesthesia groups using propensity score matching.

RESULTS

Extubation recall was observed in 28 patients (17%). After propensity score matching, the incidence of extubation recall did not significantly differ between the remimazolam and propofol anesthesia groups (15.6% vs. 18.8%; p = 1.000).

CONCLUSION

The incidence of extubation recall after remimazolam anesthesia with flumazenil antagonism during emergence did not significantly differ from that after propofol anesthesia.

What is the best technic to dislodge Staphylococcus epidermidis biofilm on medical implants?

Background

Bacterial biofilm can occur on all medical implanted devices and lead to infection and/or dysfunction of the device.

In this study, artificial biofilm was formed on four different medical implants (silicone, piccline, peripheral venous catheter and endotracheal tube) of interest for our daily clinical and/or research practice. We investigated the best conventional technic to dislodge the biofilm on the implants and quantified the number of bacteria. Staphylococcus epidermidis previously isolated from a breast implant capsular contracture on a patient in the university hospital of Dijon was selected for its ability to produce biofilm on the implants. Different technics (sonication, Digest-EUR®, mechanized bead mill, combination of sonication plus Digest-EUR®) were tested and compared to detach the biofilm before quantifying viable bacteria by colony counting.

Results

For all treatments, the optical and scanning electron microscope images showed substantial less biofilm biomass remaining on the silicone implant compared to non-treated implant.

This study demonstrated that the US procedure was statistically superior to the other physical treatment: beads, Digest-EUR® alone and Digest-EUR® + US (p < 0.001) for the flexible materials (picc-line, PIV, and silicone). The number of bacteria released by the US is significantly higher with a difference of 1 log on each material. The result for a rigid endotracheal tube were different with superiority for the chemical treatment dithiothreitol: Digest-EUR®. Surprisingly the combination of the US plus Digest-EUR® treatment was consistently inferior for the four materials.

Conclusions

Depending on the materials used, the biofilm dislodging technique must be adapted. The US procedure was the best technic to dislodge S. epidermidis biofilm on silicone, piccline, peripheral venous catheter but not endotracheal tube. This suggested that scientists should compare themselves different methods before designing a protocol of biofilm study on a given material.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-022-02606-x.

Efficacy of using an intravenous catheter to repair damaged expansion lines of endotracheal tubes and laryngeal masks

Background

 In perioperative care or intensive care units, the expansion lines of endotracheal tubes (ETTs) or laryngeal mask airways (LMAs) may be accidentally cut off during medical procedures. We designed a simple method for repairing damaged ETT and LMA expansion lines.

Methods

 In this in vitro study, ETT (n = 20) or LMA (n = 20) models were each categorized into experimental (n = 10) and control (n = 10) groups. In the experimental groups, the expansion lines were cut in the middle, and a 22G intravenous catheter was inserted into the broken end of each expansion line. The time taken to repair the expansion lines was recorded in both experimental groups. The repaired expansion lines in both groups were tested for visible underwater air leakage with cuffs under high pressure (120 cm H2O). After 15 h, the cuff pressure and tensile strength of the expansion lines were measured.

Results

 The overall time required to repair the expansion line was 27.8 ± 1.5 s in the ETT group and 20.4 ± 1.1 s in the LMA group. When the cuff pressure was increased to 120 cmH₂O, no air leakage was observed in the experimental LMA and ETT groups. The mean difference in the cuff pressures of the control and experimental groups was insignificant for both, ETT (9.50 ± 1.29 vs. 9.50 ± 1.08 cmH₂O, 95% CI =  − 1.11 to 1.11 cmH₂O, P = 1.00) and LMA (34.1 ± 1.10 cmH₂O vs. 34.5 ± 0.97 cmH₂O, 95% CI =  − 0.57 to 1.37 cmH₂O, P = 0.40) groups, The tensile strength and the force required to pull apart the expansion lines in the experimental groups were lower than those in the control groups for ETTs (3.32 ± 0.37 N vs. 35.03 ± 4.47 N, 95% CI =  − 34.69 to − 28.72 N, P < 0.0001) and LMAs (36.55 ± 2.20 N vs. 26.18 ± 1.67 N, 95% CI =  − 12.21 to − 8.53 N, P < 0.0001).

Conclusion

 An intravenous catheter can be directly inserted into the damaged ETT or LMA expansion lines; it is a simple, rapid, and effective repair method.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01776-5.

Adverse event using Medtronic NIM™ EMG endotracheal tube on a patient receiving anesthesia for hemithyroidectomy: a case report

Background

The neural integrity monitor (NIM) electromyogram (EMG) endotracheal (ET) tube is a widely used device to monitor neural response through muscle activity. It is helpful in surgical procedures with high risk of damaging delicate structures in the head and neck. This case provides a thorough analysis of an adverse event that was encountered in the operating room, which others can hopefully learn from.

Case presentation

We are reporting a case in which a patient undergoing hemithyroidectomy had experienced an adverse event using the Medtronic NIM^™ EMG endotracheal tube. After successful induction and intubation, confirming the proper positioning of the electrode wires was necessary before the incision could be made. Upon reexamination, the patient suddenly became difficult to ventilate with increased peak airway pressure, decreased tidal volume, and end tidal CO2. This episode lasted approximately 15 min and the patient’s condition remained stable despite low tidal volumes. The problem was unexpectedly resolved upon deflation of the cuff of the ET tube.

Conclusions

There are several similar reports of these endotracheal tubes causing obstruction, especially those in which overinflation of the cuff caused cuff herniation and blockage of the Murphy eye and the bevel. It is currently believed that the design of this tube allowed for the obstruction to occur. The patient’s short body habitus may have also been a small contributing factor. The distance that the electrodes must sit within the vocal cords to the tip of the bevel is longer in this type of ET tube compared with a standard ET tube. The distance from the true vocal cords to where the cuff sits in the trachea is also greater in this model NIM EMG tube. There was no confirmation of the exact obstructive process that took place, however, confirming the tube and cuff positioning would have been optimal.

Effects of lidocaine administration via the perforated outer cuff of a dual-cuff endotracheal tube and remifentanil administration on recovery from general anaesthesia for female patients undergoing thyroidectomy: a single centre, double-blind, randomised study

Background

Cough caused by endotracheal tube (ETT) placement is ubiquitous and correlates with adverse outcomes. Remifentanil administration via target-controlled infusion (TCI) is one of the cough prevention measures used during recovery. In a pilot study, lidocaine administered via the perforated outer cuff of a dual-cuff endotracheal tube was also found to prevent cough due to ETT placement. We therefore compared these two cough prevention approaches during recovery after thyroidectomy in a single-centre, double-blind, randomised study conducted in China during the period from 09/10/2020 to 30/04/2021.

Methods

Ninety-eight female patients aged 18–65 years with American Society of Anaesthesiologists Physical Status scores of I and II were scheduled to undergo thyroidectomy. The ETT contained an internal cuff covered by a perforated outer cuff to allow for lidocaine delivery. Patients were randomised to receive either 4 ml of saline solution (Group R, n = 49) or 4 ml of 2% lidocaine in the outer cuff (Group L, n = 49) at the beginning of skin suturing. Remifentanil (2 ng/ml) was maintained in Group R until extubation, while remifentanil was maintained in Group L until the end of skin suturing. The primary outcome was cough during patient transfer, at 1 min before extubation, and at extubation. The secondary outcomes were haemodynamics and other recovery parameters.

Results

Primary outcomes were compared between remifentanil vs. lidocaine application, namely, the incidence of cough during patient transfer (0% in Group R vs. 0% in Group L), at 1 min before extubation (22.45% in Group R vs. 4.08% in Group L; P = 0.015), and at extubation (61.22% in Group R vs. 20.41% in Group L; P < 0.001). Compared with remifentanil, lidocaine more effectively decreased heart rate elevation and hypoxemia at 5 min after extubation, the spontaneous respiration recovery time, the extubation time, the duration of post-anaesthesia care unit (PACU) stay, Richmond Agitation-Sedation Scale scores in the agitated range and Critical-Care Pain Observation Tool scores.

Conclusion

Lidocaine administered via the perforated outer cuff of the ETT significantly improved recovery from general anaesthesia compared to remifentanil in female patients after thyroidectomy.

Trial registration

Chinese Clinical Trial Registry (No. ChiCTR2000038653), registered on 27/09/2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01734-1.

Perianesthesia emergency repair of a cut endotracheal tube’s inflatable tube: A case report

BACKGROUND

During the perianesthesia period, emergency situations threatening the life and safety of patients can occur at any time. When dealing with some emergencies, occasional confusion is inevitable.

CASE SUMMARY

This case report describes the rare situation wherein a surgeon inadvertently detached the inflatable tube of an endotracheal tube during a tonsillectomy, and positive pressure ventilation could not be provided. While reintubation may increase the risk of respiratory tract infection and aspiration, patients with a difficult airway might die due to apnea. The best treatment method is to optimize the damaged tracheal tube junction to avoid secondary intubation and ensure patient safety. An intravenous needle and cannula were used to repair the damaged gap in the current case. Following the repair, the anesthesia machine showed no indication of low tidal volume, and there was no deflation of the endotracheal tube cuff. Subsequently, the patient was transferred to the post-anesthesia recovery room, and the tracheal tube was removed with satisfactory results.

CONCLUSION

Using an intravenous needle to repair a break in the inflatable tube surrounding an endotracheal tube is safe and reliable.

Positive signs on physical examination are not always indications for endotracheal tube intubation in patients with facial burn

Background

After clinical evaluation in the emergency department (ED), facial burn patients are usually intubated to protect their airways. However, the possibility of unnecessary intubation or delayed intubation after admission exists. Objective criteria for the evaluation of inhalation injury and the need for airway protection in facial burn patients are needed.

Methods

Facial burn patients between January 2013 and May 2016 were reviewed. Patients who were and were not intubated in the ED were compared. All the intubated patients received routine bronchoscopy and laboratory tests to evaluate whether they had inhalation injuries. The patients with and without confirmed inhalation injuries were compared. Multivariate logistic regression analysis was used to identify the independent risk factors for inhalation injuries in the facial burn patients. The reasons for intubation in the patients without inhalation injuries were also investigated.

Results

During the study period, 121 patients were intubated in the ED among a total of 335 facial burn patients. Only 73 (60.3%) patients were later confirmed to have inhalation injuries on bronchoscopy. The comparison between the patients with and without inhalation injuries showed that shortness of breath (odds ratio = 3.376, p = 0.027) and high total body surface area (TBSA) (odds ratio = 1.038, p = 0.001) were independent risk factors for inhalation injury. Other physical signs (e.g., hoarseness, burned nostril hair, etc.), laboratory examinations and chest X-ray findings were not predictive of inhalation injury in facial burn patients. All the patients with a TBSA over 60% were intubated in the ED even if they did not have inhalation injuries.

Conclusions

In the management of facial burn patients, positive signs on conventional physical examinations may not always be predictive of inhalation injury and the need for endotracheal tube intubation in the ED. More attention should be given to facial burn patients with shortness of breath and a high TBSA. Airway protection is needed in facial burn patients without inhalation injuries because of their associated injuries and treatments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-022-00594-9.

Extubation strategies after esophageal atresia repair

BACKGROUND/PURPOSE

Early extubation following repair of esophageal atresia (EA) is desirable unless the anastomosis is under tension, in which case paralysis and post-operative ventilation may reduce the risk of anastomotic leakage. However, complications from emergency reintubations do occur with either strategy. We aim to examine the risk/benefit balance of early and delayed extubation following EA repair.

METHODS

A seven-year retrospective review of all babies that underwent EA repair was performed. Babies extubated within 24 h of surgery were classified as early extubation (EE). Babies intubated beyond the first 24 h were classified as delayed extubation (DE). The EE group was subdivided into babies extubated in operating room (EIOR), and babies who returned to the neonatal intensive care unit (NICU) intubated but extubated within 24 h (EW24).

RESULTS

Forty-six babies were analyzed, and overall 15 (32.6%) required 24 reintubation episodes. Eight (28.6%) babies in the EE group required reintubation. The EIOR group (n = 12) had significantly increased risk of requiring reintubation (OR:7, 95%CI:1.08 to 45.16:p = 0.04) compared to the EW24 group (n = 16). Seven (38.9%) babies in the DE group required reintubation. The complication rate from reintubation after EA repair was 17%.

CONCLUSIONS

Extubation on the NICU within 24 h of surgery carried the lowest risk of reintubation. For babies with a tight anastomosis, elective postoperative ventilation appeared to confer a protective benefit without incurring a high risk of complications from reintubation.

Prevention of ventilator-associated pneumonia by noble metal coating of endotracheal tubes: a multi-center, randomized, double-blind study

BACKGROUND

Ventilator-associated pneumonia (VAP) causes increased mortality, prolonged hospital stay and increased healthcare costs. Prevention of VAP in intensive care units (ICUs) is currently based on several measures, and application of noble metal coating on medical devices has been shown to inhibit the bacterial adherence of microorganisms to the surface. The objective of this study was to evaluate the potential benefit of noble metal coating of endotracheal tubes for the prevention of VAP.

METHODS

This was a multi-center, randomized, controlled, double-blind, prospective study including ventilated patients from nine ICUs from four hospital sites in Belgium. Patients were randomly intubated with identical appearing noble metal alloy (NMA) coated (NMA-coated group) or non-coated (control group) endotracheal tubes (ETT). Primary endpoint was the incidence of VAP. Secondary endpoints were the proportion of antibiotic days during ICU stay and tracheal colonization by pathogenic bacteria.

RESULTS

In total, 323 patients were enrolled, 168 in the NMA-coated group and 155 in the control group. During ventilation, VAP occurred in 11 patients (6.5%) in the NMA-coated group and in 18 patients (11.6%) in the control group (p  = 0.11). A higher delay in VAP occurrence was observed in the NMA-coated group compared with the control group by Cox proportional hazards regression analysis (HR 0.41, 95% CI 0.19-0.88, p  = 0.02). The number of antibiotic days was 58.8% of the 1,928 ICU days in the NMA-coated group and 65.4% of the 1774 ICU days in the control group (p  = 0.06). Regarding tracheal colonization, bacteria occurred in 38 of 126 patients in the NMA-coated group (30.2%) and in 37 of 109 patients in the control group (33.9%) (p  = 0.57).

CONCLUSIONS

This study provides preliminary evidence to support the benefit of noble metal coating in the prevention of VAP. A confirmatory study in a larger population would be valuable.

TRIAL REGISTRATION

Clinical trial number: NCT04242706 ( http://www.clinicaltrials.gov ).

Optimising endotracheal length in adult cats: a retrospective CT study

OBJECTIVES

The aim of this study was to determine the maximal endotracheal insertion length by measuring the larynx to carina (L-C) distance by means of CT. An additional objective was to establish certain anatomical landmarks to optimise the process of endotracheal intubation (ETI).

METHODS

Head, neck and thoracic CT images from adult cats at a single referral hospital between 2013 and 2020 were retrospectively evaluated. After standardising and identifying key markers (larynx, carina and first rib) the L-C, larynx to first rib (L-1R) and first rib to carina (1R-C) distances were measured.

RESULTS

Forty-five adult cats were enrolled in the study, from which a total of nine different breeds were identified. The L-C distance was 14.3 ± 1.1 cm. This was longer in male (14.7 ± 1.1 cm) than in female cats (13.5 ± 0.7 cm). The first rib (1R) was 8.8 ± 0.7 cm from the larynx and the mean 1R-C distance was 5.4 ± 0.7 cm. The carina was found within the fifth intercostal space in 93.3% (n = 42) of the cats.

CONCLUSIONS AND RELEVANCE

The process of ETI in adult cats may be guided by using the L-C and L-1R distance for a maximal and optimal endotracheal tube introduction, respectively. In addition, the maximal insertion length may be guided by estimating the position of the carina parallel to the fifth intercostal space.

Measurement of Endotracheal Tube Positioning on Chest X-Ray Using Object Detection

Patients who are intubated with endotracheal tubes often receive chest x-ray (CXR) imaging to determine whether the tube is correctly positioned. When these CXRs are interpreted by a radiologist, they evaluate whether the tube needs to be repositioned and typically provide a measurement in centimeters between the endotracheal tube tip and carina. In this project, a large dataset of endotracheal tube and carina bounding boxes was annotated on CXRs, and a machine-learning model was trained to generate these boxes on new CXRs and to calculate a distance measurement between the tube and carina. This model was applied to a gold standard annotated dataset, as well as to all prospective data passing through our radiology system for two weeks. Inter-radiologist variability was also measured on a test dataset. The distance measurements for both the gold standard dataset (mean error = 0.70 cm) and prospective dataset (mean error = 0.68 cm) were noninferior to inter-radiologist variability (mean error = 0.70 cm) within an equivalence bound of 0.1 cm. This suggests that this model performs at an accuracy similar to human measurements, and these distance calculations can be used for clinical report auto-population and/or worklist prioritization of severely malpositioned tubes.

Assessing the accuracy of ultrasound measurements of tracheal diameter: an in vitro experimental study

Background

Recent studies indicate that ultrasound can detect changes in tracheal diameter during endotracheal tube (ETT) cuff inflation. We sought to assess the accuracy of ultrasound measurement of tracheal diameter, and to determine the relationship between tracheal wall pressure (TWP), cuff inflation volume (CIV), and the degree of tracheal deformation.

Methods

Our study comprised two parts: the first included 45 porcine tracheas, the second 41 porcine tracheas. Each trachea was intubated with a cuffed ETT, which was connected to an injector and the manometer via a three-way tap. The cuff was inflated and the cuff pressure recorded before and after intubation. The tracheal diameter was measured using ultrasound. This included three separate measurements: outer transverse diameter (OTD), internal transverse diameter (ITD), and anterior tracheal wall thicknesses (ATWT). A precision electronic Vernier caliper was also used to measure tracheal diameter. We calculated TWP and the percentage change of tracheal diameter. The Bland–Altman method, linear regression, and locally weighted regression (LOESS) were used to analyze the data.

Results

There were strong correlation and agreement for OTD (r = 0.97, P < 0.001) and ITD (r = 0.90, P < 0.001) as measured by ultrasound and by precision electronic Vernier caliper, but a poor correlation for ATWT (r = 0.58, P < 0.001). There was a strong correlation between the percentage change of OTD (OTD%, r = 0.75, P < 0.001) and CIV, the percentage change of ITD (ITD%, r = 0.77, P < 0.001) and CIV, TWP (r = 0.75, P < 0.001) and CIV. And a strong correlation was also found between TWP and OTD% (r = 0.84, P < 0.001), TWP and ITD% (r = 0.84, P < 0.001).

Conclusions

Use of ultrasound to measure OTD and ITD is accurate, but is less accurate for ATWT. There is a close correlation between OTD%, ITD%, CIV and TWP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01398-3.

Is Ultrasonography a Better Method of Endotracheal Tube Size Estimation in Pediatric Age Group than the Conventional Physical Indices-Based Formulae?

Background:

Providing safe anaesthesia to paediatric patients is a challenging task. This requires a thorough knowledge of the soft and pliable paediatric airway. Owing to the vulnerability of the anatomical structures involved, choosing an appropiate sized endotracheal tube (ETT) is important in these cases. A larger sized ETT may lead to trauma and a smaller one would result in leakage and risk of aspiration. Both situations demand an immediate tube change, thereby complicating the condition. The physical indices- based formulae have often failed to justify the purpose leading to repeated laryngoscopy and tube change during intubation. The increase in availability of the modern ultrasound devices have shown promise in these cases.

Aims and Objectives:

In this study we examine the accuracy of ultrasonography (USG)to assess the appropriate ETT size, comparing it with physical indices based formulae suggested ETT size so that repeated attempts on intubation can be minimized.

Materials and Methods:

The study group included 100 patients of 1-5 years, ASA I- II, requiring orotracheal intubation under general anaesthesia. The tracheal sub-glottic diameter was estimated by pre-anaesthetic USG to determine the ETT size, both cuffed and uncuffed. ETT data obtained by these methods were compared by Pearson's correlation coefficient and t-test.

Results:

USG predicted ETT size were significantly more consistent than the physical indices based formulae. Also the age based formulae were found to be more precise than the height based ones. Seven patients required change of tube once.

Conclusion:

Ultrasonography is an effective tool in predicting paediatric ETT size.

Laryngeal mask versus endotracheal tube for airway management in tracheal surgery: a case-control matching analysis and review of the current literature

OBJECTIVES

The endotracheal tube (ETT) and the laryngeal mask airway (LMA) are possible strategies for airway management during tracheal resection and reconstruction for tracheal and laryngotracheal stenosis. The goal of the study was to analyse and compare outcomes in the LMA and ETT groups.

METHODS

Between 2003 and 2020, a total of 184 patients affected by postintubation, post-tracheostomy and idiopathic stenosis who had tracheal or laryngotracheal resections and reconstructions via a cervicotomy were retrospectively enrolled in this single-centre study. In 29 patients, airway management was achieved through LMA during tracheal surgery, whereas in 155 patients, it was achieved through ETT. A case-control matching analysis was performed with a 1:1 ratio, according to age, gender, body mass index, aetiology and length of stenosis (1-4 cm), resulting in 22 patients managed through LMA (LMA group) matched with 22 patients managed through ETT (ETT group).

RESULTS

No significant differences were found in the reintubation rate, 30-day mortality and postoperative length of stay. Operative time was shorter in patients with LMA (96.23 ± 34.72 min in the ETT group vs 76.14 ± 26.94 min in the LMA group; P = 0.043). Intensive care unit (ICU) admission rate and stay were lower in the LMA group [18 in the ETT group vs 8 in the LMA group, odds ratio = 10.17, confidence interval (CI) 95% 1.79-57.79; P = 0. 009; 22.77 ± 16.68 h in ETT group vs 9.23 ± 13.51 h in LMA group; P = 0.005]. Dysphonia was more frequent in the ETT group than in the LMA group (20 in the ETT group vs 11 in the LMA group, odds ratio = 13.79, CI 95% 1.86-102; P = 0.010).

CONCLUSIONS

LMA is a feasible option for airway management in tracheal surgery, with lower operative time, ICU admission rate, ICU length of stay and postoperative dysphonia occurrence.

'Lip-to-Tip' study: comparison of three methods to determine optimal insertion length of endotracheal tube in neonates

The aim of this prospective observational study was to compare the incidence of endotracheal tube (ETT) malposition using weight-based (Tochen), gestation-based (Kempley), and nasotragal length (NTL) methods in deceased neonates and fresh stillbirths. We enrolled deceased neonates and fresh stillbirths within 2 ± 1 h of death or delivery, respectively; without hydrops, tracheostomy or major congenital anomalies affecting face, neck, or thorax. Each enrolled subject was intubated orotracheally, with lip-to-tip distance determined by three methods in random succession. Chest X-ray was acquired after each insertion. The primary outcome was proportion of malpositioned ETTs on chest X-ray (defined as ETT tip not lying between upper border of T1 and lower border of T2 vertebrae), assessed by two experts masked to the methods used. The proportion of malpositioned tubes was not significantly different with any of the three methods: (weight 27/50 (54%), gestation 35/50 (70%), and NTL 35/50 (70%), p value 0.055). The malpositioned tubes were too far in (87/150; 58%) than too far out (10/150; 6.7%).Conclusions: None of the currently recommended methods accurately predicts optimal ETT length in neonates. There is an urgent need for newer bedside modalities for estimating ETT position in neonates. What is known? • NRP guidelines recommend gestation-based and nasotragal length (NTL) methods to estimate initial ETT depth in neonates. Weight-based (Tochen) method is still widely used in neonatal units for ETT depth estimation. Evidence till date has not proven superiority of one method over the other. What is new? • All three methods for ETT depth estimation (Tochen, gestation-based, and NTL) resulted in high rates of ETT malposition in neonates. Formulae, devised from this study based on linear regression models, did not perform well for estimation of optimal ETT position.

How to Prevent Endotracheal Tube Cuff Overinflation: "5 for 25"

Adverse effects associated with elevated endotracheal (ET) tube cuff pressures above 25 cm H2O include postoperative throat pain and tissue ischemia. Anesthesia practitioners' current methods of cuff pressure estimation are often inaccurate. This quantitative, quasi-experimental quality improvement project evaluated the incidence of ET tube cuff overinflation before and after an educational intervention that recommended the use of a 5-mL over 10-mL syringe for cuff inflation. Cuff pressures were measured at 2 hospitals within a large academic health system. The mean ET tube cuff pressure before education was 46.8 cm H2O and after education was 27.1 cm H2O (P=.001). The postintervention average cuff pressure using a 10-mL syringe was 36.8 cm H2O vs 21.1 cm H2O when providers used a 5-mL syringe (P=.039). The relationship between syringe size and cuff pressure was significant (P=.001) with a positive Pearson correlation of 0.471. The ET tube cuff pressures were reduced by 42% after the intervention. Average cuff pressures when providers used a 5-mL syringe were 55% lower than with use of a 10-mL syringe. No critically high postintervention pressures were recorded when a 5-mL syringe was used. The authors recommend 5-mL syringes be used for inflation of an ET tube cuff.

Comparison of the Baska Mask® and Endotracheal Tube on Hemodynamic and Respiratory Parameters in Septoplasty Cases

Laryngeal mask (LM) types have been used as an airway device for an alternative to the standard endotracheal tube (ETT). One of the novel type of LM, the Baska Mask®, can be a safe alternative among the airway devices. The purpose of this study is to compare the effects of the new generation supraglottic airway device the Baska Mask® and the ETT on hemodynamic parameters (heart rate, mean arterial pressure), airway pressure and end tidal carbon dioxide (EtCO2) in patients undergoing general anesthesia. After the approval of the ethics committee, 70 patients who underwent septoplasty were included in the study. Written informed consent forms were taken from these patients. Demographic data of the patients were recorded. Hemodynamic data of patients were measured and recorded preoperative, during induction, at the time of intubation 1th, 3th and 5th minute and during extubation. Also, airway pressure and EtCO2 values of the patients were measured and recorded at the time of intubation, 1th, 3th and 5th minutes. Demographic data were similar in both groups. Mean arterial pressure, heart rate and airway pressure were lower in the group 2 (the Baska Mask® group) than in the group 1 (ETT group) and the difference was statistically significant (p&lt;0.05). EtCO2 values were similar in both groups. No patients had tube leakage. In terms of hemodynamic and respiratory parameters the Baska Mask® is more advantageous than the ETT in short-term surgeries.

Emergency videoendoscopic endonasal tracheal intubation for severe upper airway stenosis

PURPOSE

Upper airway stenosis is one of the most formidable situations in medicine and is frequently encountered in the ENT clinic. We introduce here our method of emergency endonasal endotracheal intubation under videoendoscopic observation.

METHODS

Transnasal endoscopic observation was done, and the region of airway stenosis was detected. Then, the endotracheal tube was prepared and the endoscope was inserted into the tube. The endoscope with tube was inserted up to the larynx. Immediately after the administration of lidocaine to the larynx, the endoscope with tube was inserted to the endolarynx and then to the trachea. The endotracheal tube was tightly held in the nostril, and the endoscope was removed.

RESULTS

We have encountered four cases this year. The primary disease developing airway stenosis was acute epiglottitis due to pharyngeal and deep neck abscesses in three cases and laryngeal edema due to Ludwig's angina. All patients underwent uneventful intubation, and dyspnea was immediately ceased.

CONCLUSION

In cases showing severe suffocation, the clinician should perform airway maintenance even in an outpatient setting apart from a more monitored setting like the operation room. This technique resembles the usual nasal endoscopic laryngeal observation and is done even in the usual ENT office and/or emergency room. The supine position tends to worsen airway stenosis in patients with upper airway stenosis; however, this technique can be performed in a sitting or semi-sitting position. This method is less invasive for patients and also reduces the risk to the medical staff, especially in this COVID-19 era.

Comparison and evaluation of single-use LMA supreme versus the reusable proseal LMA in paralyzed patients undergoing surgery with controlled ventilation

Background and Aims:

The objective of this prospective randomized blinded study was to assess the safety and efficacy of the laryngeal mask airway (LMA) Supreme as compared with the LMA Proseal.

Material and Methods:

A total of 60 patients were randomised into two groups to either receive a Proseal LMA (PLMA) or Supreme LMA (SLMA) for airway management. The primary outcome was to measure oropharyngeal leak pressure (OLP) in both groups. The secondary outcomes were the measurement of insertion time, insertion success rate, fibreoptic grading, intracuff pressure, ease of ventilation, and airway pressure on standard ventilatory settings and postoperative complications.

Results:

Intracuff pressure increase after 60 minutes of induction was significantly higher in the PLMA group (PLMA 97.43 ± 11.03 cm of H₂O and SLMA 75.17 ± 8.95 cm of H₂O). OLP was recorded after device insertion, after 30 min and after 60 min in each group and was found to be 28.71 ± 2.97, 30.93 ± 2.87, and 31.93 ± 2.72 cm of H₂O in PLMA and 24.84 ± 2.08, 26.73 ± 2.26, and 27.95 ± 2.55 cm of H₂O in SLMA group, respectively. The mean OLP with the SLMA was significantly (p=<.001) lower than PLMA. All the other parameters were comparable in both groups.

Conclusion:

PLMA is better than SLMA as airway device to ventilate at higher airway pressure in paralyzed adult patients. On the basis of our study, we recommend Proseal over Supreme LMA.

Utility of Endotracheal Tube Cuff Pressure Monitoring in Mechanically Ventilated (MV) Children in Preventing Post-extubation Stridor (PES)

Objective

To study if protocolized monitoring of endotracheal tube (ETT) cuff pressure every 6 hours is better than adjusting endotracheal tube cuff inflation by the only bedside clinical assessment.

Materials and methods

This was a single-center prospective randomized controlled study done between July 1, 2017 and March 31, 2019. Children between 1 month and 18 years, intubated with cuffed ETT by our trained doctors were included. After obtaining consent, patients were randomized into two groups, standard group (SG) and cuff pressure monitoring group (MG). Sample size was calculated with 80 patients in each group with a power of 80%, significance level (alpha 0.05 and beta 0.2). In the SG, ETT cuff inflation was adjusted by clinical assessment (bedside minimal leak technique and monitoring the percentage of leak displayed on ventilator display) at 6 hours interval. In the MG, cuff pressures were monitored by the device every 6 hours to maintain between 20 and 25 mm Hg.

Results

Out of 543 mechanically ventilated children during the study period, 266 were eligible and randomized for study. During the study, 89 patients died and 17 were left against medical advice, leaving 80 patients in each group. Incidence of post-extubation stridor (PES), re-intubation rate, ventilator-associated pneumonia (VAP) rate, ventilator days, and length of pediatric intensive care unit (PICU) stay were analyzed and found no advantage of protocolized monitoring of cuff pressures in the reduction of any of the above variables.

Conclusion

Our findings if confirmed by large multicentric studies can bring an end to routine ETT cuff pressure measurements and emphasize more on clinical assessment. Clinical trial registry (CTRI/2019/05/019098).

Indian Journal of Critical Care Medicine (2021): 10.5005/jp-journals-10071-23737

How to cite this article

Shaikh F, Janaapureddy YR, Mohanty S, Reddy PK, Sachane K, Dekate PS, et al. Utility of Endotracheal Tube Cuff Pressure Monitoring in Mechanically Ventilated (MV) Children in Preventing Post-extubation Stridor (PES). Indian J Crit Care Med 2021;25(2):181–184.

Effect of routine vs on-demand nebulization of acetylcysteine with salbutamol on accumulation of airway secretions in endotracheal tubes: substudy of a randomized clinical trial

BACKGROUND

Accumulated airway secretions in the endotracheal tube increase work of breathing and may favor airway colonization eventually leading to pneumonia. The aim of this preplanned substudy of the 'Preventive Nebulization of Mucolytic Agents and Bronchodilating Drugs in Intubated and Ventilated Intensive Care Unit Patients trial' (NEBULAE) was to compare the effect of routine vs on-demand nebulization of acetylcysteine with salbutamol on accumulation of secretions in endotracheal tubes in critically ill patients.

RESULTS

In this single-center substudy of a national multicenter trial, patients were randomized to a strategy of routine nebulizations of acetylcysteine with salbutamol every 6 h until end of invasive ventilation, or to a strategy with on-demand nebulizations of acetylcysteine or salbutamol applied on strict clinical indications only. The primary endpoint, the maximum reduction in cross-sectional area (CSA) of the endotracheal tube was assessed with high-resolution computed tomography. Endotracheal tubes were collected from 72 patients, 36 from patients randomized to the routine nebulization strategy and 36 of patients randomized to the on-demand nebulization strategy. The maximum cross-sectional area (CSA) of the endotracheal tube was median 12 [6 to 15]% in tubes obtained from patients in the routine nebulization group, not different from median 9 [6 to 14]% in tubes obtained from patients in the on-demand nebulization group (P = 0.33).

CONCLUSION

In adult critically ill patients under invasive ventilation, routine nebulization of mucolytics and bronchodilators did not affect accumulation of airway secretions in the endotracheal tube. Trial registration Clinicaltrials.gov Identifier: NCT02159196.

Novel expandable architected breathing tube for improving airway securement in emergency care

Life-saving interventions utilize endotracheal intubation to secure a patient's airway, but performance of the clinical standard of care endotracheal tube (ETT) is inadequate. For instance, in the current COVID-19 crisis, patients can expect prolonged intubation. This protracted intubation may produce health complications such as tracheal stenosis, pneumonia, and necrosis of tracheal tissue, as current ETTs are not designed for extended use. In this work, we propose an improved ETT design that seeks to overcome these limitations by utilizing unique geometries which enable a novel expanding cylinder. The mechanism provides a better distribution of the contact forces between the ETT and the trachea, which should enhance patient tolerability. Results show that at full expansion, our new ETT exerts pressures in a silicone tracheal phantom well within the recommended standard of care. Also, preliminary manikin tests demonstrated that the new ETT can deliver similar performance in terms of air pressure and air volume when compared with the current gold standard ETT. The potential benefits of this new architected ETT are threefold, by limiting exposure of healthcare providers to patient pathogens through streamlining the intubation process, reducing downstream complications, and eliminating the need of multiple size ETT as one architected ETT fits all.

Efficacy of intracuff lidocaine in reducing coughing on tube: a systematic review and meta-analysis

Objective

Method

Results

Conclusion

Simulator-based ultrasound training for identification of endotracheal tube placement in a neonatal intensive care unit using point of care ultrasound

BACKGROUND

Simulators are an extensively utilized teaching tool in clinical settings. Simulation enables learners to practice and improve their skills in a safe and controlled environment before using these skills on patients. We evaluated the effect of a training session utilizing a novel intubation ultrasound simulator on the accuracy of provider detection of tracheal versus esophageal neonatal endotracheal tube (ETT) placement using point-of-care ultrasound (POCUS). We also investigated whether the time to POCUS image interpretation decreased with repeated simulator attempts.

METHODS

Sixty neonatal health care providers participated in a three-hour simulator-based training session in the neonatal intensive care unit (NICU) of Aga Khan University Hospital (AKUH), Karachi, Pakistan. Participants included neonatologists, neonatal fellows, pediatric residents and senior nursing staff. The training utilized a novel low-cost simulator made with gelatin, water and psyllium fiber. Training consisted of a didactic session, practice with the simulator, and practice with intubated NICU patients. At the end of training, participants underwent an objective structured assessment of technical skills (OSATS) and ten rounds of simulator-based testing of their ability to use POCUS to differentiate between simulated tracheal and esophageal intubations.

RESULTS

The majority of the participants in the training had an average of 7.0 years (SD 4.9) of clinical experience. After controlling for gender, profession, years of practice and POCUS knowledge, linear mixed model and mixed effects logistic regression demonstrated marginal improvement in POCUS interpretation over repeated simulator testing. The mean time-to-interpretation decreased from 24.7 (SD 20.3) seconds for test 1 to 10.1 (SD 4.5) seconds for Test 10, p < 0.001. There was an average reduction of 1.3 s (β = - 1.3; 95% CI: - 1.66 to - 1.0) in time-to-interpretation with repeated simulator testing after adjusting for the covariates listed above.

CONCLUSION

We found a three-hour simulator-based training session had a significant impact on technical skills and performance of neonatal health care providers in identification of ETT position using POCUS. Further research is needed to examine whether these skills are transferable to intubated newborns in various health settings.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03533218 . Registered May 2018.

A comparative study of the Parker Flex-Tip tube versus standard portex tube for oral fiberoptic intubation in bronchoscopy performed by pulmonologists with limited experience

BACKGROUND

Fiberoptic tracheal intubation (FTI) in bronchoscopy is widely performed with a conventional Portex tracheal tube (PTT). Occasionally, it is difficult for pulmonologists with limited experience to insert a tube beyond the vocal cords and advance it into the trachea. A new endotracheal tube, the Parker Flex-Tip tube (PFT), was recently designed. We compared the usefulness and safety of PFT versus PTT for FTI in bronchoscopy performed by pulmonologists with limited experience.

METHODS

Forty consecutive patients were enrolled and randomly assigned to either the PFT group (n = 20) or PTT group (n = 20). The time required for the tip of the endotracheal tube to pass from the mouth to the carina, the number of vomiting reflexes, the number of attempts to pass the tube through the vocal cords during intubation, complications, and technical difficulty of intubation were evaluated.

RESULTS

Both the PFT and PTT groups exhibited high intubation success rates (100% vs. 90%, respectively). The PFT group was intubated faster than the PTT group (11.5 [5-45] s vs. 22.5 [8-270] s, respectively, p < 0.01). The PFT group showed fewer vomiting reflexes and tube impingements than the PTT group (p < 0.05). Operators felt it was easier to intubate with PFT versus PTT (p < 0.01). Complications were not significantly different between the two groups.

CONCLUSION

For pulmonologists with limited experience who perform FTI in bronchoscopy, intubation using PFT versus PTT is faster and easier, without an increase in complications.

Endotracheal tube inflation tubing defect: an unusual cause of intraoperative volume leak

Loss of endotracheal cuff pressure can lead to airway compromise and loss of volume delivery in mechanical ventilation requiring immediate intervention. A 40 years old male posted for bilateral interpositional arthroplasty was intubated nasally with 7.5 mm flexometallic endotracheal tube. In the intraoperative period airway leak was detected due to loss of cuff pressure even after repeated attempt of cuff inflation. After changing endotracheal tube, leak was detected from the inflation tubing distal to the cuff, which was apparent only when cuff pressure was increased above 30 cm of H₂O.

Selective digestive decontamination solution used as "lock therapy" prevents and eradicates bacterial biofilm in an in vitro bench-top model

Background

Most preventing measures for reducing ventilator-associated pneumonia (VAP) are based mainly on the decolonization of the internal surface of the endotracheal tubes (ETTs). However, it has been demonstrated that bacterial biofilm can also be formed on the external surface of ETTs. Our objective was to test in vitro the efficacy of selective digestive decontamination solution (SDDs) onto ETT to prevent biofilm formation and eradicate preformed biofilms of three different microorganisms of VAP.

Methods

We used an in vitro model in which we applied, at the subglottic space of ETT, biofilms of either P. aeruginosa ATCC 15442, or E. coli ATCC 25922, or S. aureus ATCC 29213, and the SDDs at the same time (prophylaxis) or after 72 h of biofilm forming (treatment). ETT were incubated during 5 days with a regimen of 2 h-locks. ETT fragments were analyzed by sonication and confocal laser scanning microscopy to calculate the percentage reduction of cfu and viable cells, respectively.

Results

Median (IQR) percentage reduction of live cells and cfu/ml counts after treatment were, respectively, 53.2% (39.4%—64.1%) and 100% (100%–100.0%) for P. aeruginosa, and 67.9% (46.7%–78.7%) and 100% (100%–100.0%) for E. coli. S. aureus presented a complete eradication by both methods. After prophylaxis, there were absence of live cells and cfu/ml counts for all microorganisms.

Conclusions

SDDs used as “lock therapy” in the subglottic space is a promising prophylactic approach that could be used in combination with the oro-digestive decontamination procedure in the prevention of VAP.

Symptom clusters in head and neck cancer patients with endotracheal tube: Which symptom clusters are independently associated with health-related quality of life?

PURPOSE

The point of view of symptom clusters (SCs) may develop an efficient symptom management strategy to enhance health-related quality of life (HRQoL) in head and neck (HNC) patients with endotracheal tube (ETT). The study aims to investigate the possible SCs in HNC patients with ETT and determine whether there was an independent relationship between one or more SCs and HRQoL.

METHODS

A cross-sectional study design was adopted, and 203 HNC patients with ETT were recruited. They took measurements of General Information Questionnaire, MD Anderson Symptom Inventory-Head & Neck, and Twelve-Item Short-Form Health Survey (SF-12). Spearman correlations, partial correlations, and hierarchical cluster analysis were performed to determine latent number of SCs, and covariance analyses were used to determine independent associations between SCs and SF-12. This study followed STROBE Statement.

RESULTS

Pain SCs (pain, distressed, short of breath, and sadness), fatigue SCs (fatigue/weakness, restless, and sleepy), digestive SCs (appetite loss, constipation, and nausea), HNC-specific SCs (dry mouth and mucus), and tracheostomy-related SCs (difficulty swallowing and difficulty with voice and speech) were found. After adjusting covariant variables, this study found independent relationships of pain SCs and fatigue SCs with physical component summary of SF-12, and between fatigue SCs and mental component summary of SF-12.

CONCLUSIONS

Multiple SCs were found in those HNC patients. Pain SCs and fatigue SCs were independently associated with HRQoL. In process of caring HNC patients with ETT, it is vital to focus on SCs, especially on pain SCs and fatigue SCs, which might effectively improve patients' HRQoL.