Artificial Intelligence to Assess Tracheal Tubes and Central Venous Catheters in Chest Radiographs Using an Algorithmic Approach With Adjustable Positioning Definitions

PURPOSE

To develop and validate an artificial intelligence algorithm for the positioning assessment of tracheal tubes (TTs) and central venous catheters (CVCs) in supine chest radiographs (SCXRs) by using an algorithm approach allowing for adjustable definitions of intended device positioning.

MATERIALS AND METHODS

Positioning quality of CVCs and TTs is evaluated by spatially correlating the respective tip positions with anatomical structures. For CVC analysis, a configurable region of interest is defined to approximate the expected region of well-positioned CVC tips from segmentations of anatomical landmarks. The CVC/TT information is estimated by introducing a new multitask neural network architecture for jointly performing type/existence classification, course segmentation, and tip detection. Validation data consisted of 589 SCXRs that have been radiologically annotated for inserted TTs/CVCs, including an experts' categorical positioning assessment (reading 1). In-image positions of algorithm-detected TT/CVC tips could be corrected using a validation software tool (reading 2) that finally allowed for localization accuracy quantification. Algorithmic detection of images with misplaced devices (reading 1 as reference standard) was quantified by receiver operating characteristics.

RESULTS

Supine chest radiographs were correctly classified according to inserted TTs/CVCs in 100%/98% of the cases, thereby with high accuracy in also spatially localizing the medical device tips: corrections less than 3 mm in >86% (TTs) and 77% (CVCs) of the cases. Chest radiographs with malpositioned devices were detected with area under the curves of >0.98 (TTs), >0.96 (CVCs with accidental vessel turnover), and >0.93 (also suboptimal CVC insertion length considered). The receiver operating characteristics limitations regarding CVC assessment were mainly caused by limitations of the applied CXR position definitions (region of interest derived from anatomical landmarks), not by algorithmic spatial detection inaccuracies.

CONCLUSIONS

The TT and CVC tips were accurately localized in SCXRs by the presented algorithms, but triaging applications for CVC positioning assessment still suffer from the vague definition of optimal CXR positioning. Our algorithm, however, allows for an adjustment of these criteria, theoretically enabling them to meet user-specific or patient subgroups requirements. Besides CVC tip analysis, future work should also include specific course analysis for accidental vessel turnover detection.

Characteristics of lower airway parameters in an adult Asian population related to endotracheal tube design: a cadaveric study

The risk of endotracheal tube (ETT) placement includes endobronchial intubation and subglottic injury. This study aimed to describe the lengths of lower airway parameters related to cuff location and vocal cord markings in different adult-sized ETTs. Eighty cadavers were examined for the lengths of the lower airway, including their correlations and linear regressions with height. Thirty adult-sized ETTs from seven different brands were examined for Mark-Cuff and Mark-Tip distances. The depth of ETT placement was simulated for each brand using vocal cord marking. The mean (standard deviation) lengths from the subglottis, trachea, vocal cord to mid- trachea, and vocal cord to carina were 24.2 (3.5), 97.9 (8.6), 73.2 (5.3), and 122.1 (9.0) mm, respectively. Airway lengths were estimated as: (1) subglottis (mm) = 0.173 * (height in cm) - 3.547; (2) vocal cord to mid-trachea (mm) = 0.28 * (height in cm) + 28.391. There were variations in the Mark-Cuff and Mark-Tip distances among different ETTs. In the simulation, endobronchial intubation ranged between 2.5 and 5% and the cuff in the subglottis ranged between 2.5 and 97.5%. In summary, the lower airway parameters were height-related. ETT placement using vocal cord marking puts the patient at a high risk of cuff placement in the subglottis.

Tracheal Tube Misplacement after Emergency Intubation in Pediatric Trauma Patients: A Retrospective, Exploratory Study

Inadvertent tracheal tube misplacement and particularly endobronchial intubation are well-known complications of emergency endotracheal intubation (ETI) in pediatric trauma patients, which require repositioning of the tube to avoid impairment of gas exchange. The main aim of study was to identify the frequency of tube misplacement and associated factors of pediatric trauma patients who received ETI either by prehospital physician-staffed emergency medical service (EMS), or at emergency department (ED) admission to a single level-1 trauma center. Sixty-five patients (median age 14 years and median injury severity score 29) were included. Of these, 30 underwent helicopter EMS ETI, 29 ground EMS ETI, and 6 ED ETI. Seventeen cases (26%) of tracheal tube misplacement were recognized. After multivariable analysis, tracheal tube misplacement was independently negatively associated with body weight (OR 0.86; 95% CI, 0.76–0.99; p = 0.032) and helicopter EMS ETI (OR 0.20; 95% CI, 0.04–0.97; p = 0.036). Two of nineteen patients received tube thoracostomy due to endobronchial intubation. Mortality and length of stay were comparable in patients with misplaced tubes and correctly placed tubes. The results suggest that particularly small children require attention to avoid tracheal tube misplacement, which emphasizes the need for special training. Helicopter EMS physicians’ expertise might be beneficial in prehospital pediatric trauma patients requiring advanced airway management.

Ideal Depth of Endotracheal Intubation at the Vocal Cord Level in Pediatric Patients Considering Racial Differences in Tracheal Length

Numerous formulas that can predict endotracheal intubation depth at the corner of the mouth or the nasal wing of patients have been reported, even though the oral and nasal cavity anatomies differ among patients. Therefore, the purpose of this study was to derive a simple and reliable formula to predict the ideal endotracheal tube insertion depth at the vocal cord level in pediatric patients. The current study was conducted as a retrospective observational study, involving 425 and 335 cardiac pediatric patients in Germany and Japan, respectively, and aimed to determine a formula for predicting tracheal length and ideal depth of endotracheal intubation at the vocal cord level in pediatric patients. The distance between the vocal cords and the carina tracheae was defined as the tracheal length, and was measured on preoperative chest radiographs obtained in the supine position. The tracheal length in cardiac pediatric patients ranged from 6 to 10% of the body height in Germany and from 7 to 11% in Japan. This study revealed racial differences in the tracheal length, that is, in the ideal depth of endotracheal intubation at the vocal cord level. This study suggests that an adequate endotracheal intubation depth can be achieved by inserting endotracheal tubes at the vocal cord level with the minimum tracheal length of each racial group in pediatric patients, for example, 6% and 7% of the body height in Europeans and Asians, respectively. If the endotracheal tube inserted with this method appears to be shallow on chest radiographs, this does not represent an increased risk of accidental extubation, due to an excessively short intubation depth, because the minimum tracheal length for each racial group is considered. That is, it is not due to the endotracheal tube insertion length, but is likely due to the tracheal length of the patient, who has a relatively long tracheal length in the racial group.

Pre-shaped supraglottic airway devices offer an alternative to endotracheal intubation for airway management of postburn neck contracture: A case series

Background and Aims:

Moderate to severe postburn contractures (PBCs) of the neck lead to multiple areas of difficulty in airway management. Awake flexible fiberscope guided intubation with cuffed endotracheal tube (ETT) is considered the “gold standard” for securing the airway in these cases. Supraglottic airway devices (SADs), if at all used, are used either as rescue devices or as conduits for ETT. This case series looks at the possibility of using SADs as a planned airway securing device in these cases.

Material and Methods:

We managed 24 cases of moderate to severe PBC neck using six types of pre shaped SADs as the first choice airway device. These SADs were placed after either airway topicalization (19 cases) or general anesthesia (GA) (5 cases). Once SAD placement was confirmed, all the patients received GA and muscle relaxant. Tests for proper placement and function and fiberscopy (conducted in four cases) were performed at various times during the procedure. The SADs were removed once the patients were fully awake.

Results:

SADs could be placed in one attempt in all the cases. The time taken to hand over the patients to surgeons was 12–20 min. SADs maintained their proper placement and function in spite of changing airway dimensions during contracture release. The patients tolerated the SADs well right until the time they were fully awake. The SADs could be successfully removed on the operation table in all the cases.

Conclusion:

Pre shaped SADs secure the airway quickly and are free from the risk of intraoperative displacements and allow uneventful emergence in moderate and severe PBC neck cases and need to be considered as the first choice in these cases.

Endotracheal Tube Migration in Steep Trendelenburg Position With the Estape TrenMAX Positioning System

The extent of endotracheal tube (ETT) migration was studied in 25 adult female patients undergoing robotic-assisted laparoscopic gynecologic surgery while in a steep Trendelenburg position secured with the Estape TrenMAX positioning system (Innovative Medical Products, Plainville, CT, USA). In four patients, the distance from the tip of the ETT to the carina did not change. In three patients, the distance from the tip of the ETT to the carina decreased by 1 centimeter (cm). In other patients, the distance from the tip of the ETT to the carina decreased by 0.2 to 0.5 cm. We concluded that the tip of the ETT moves closer to the carina in patients put in the extreme Trendelenburg position. These results were in alignment with the evidence base created by other researchers.

Risk factors and outcomes of unrecognised endobronchial intubation in major trauma patients

Background

Emergency tracheal intubation during major trauma resuscitation may be associated with unrecognised endobronchial intubation. The risk factors and outcomes associated with this issue have not previously been fully defined.

Methods

We retrospectively analysed adult patients admitted directly from the scene to the ED of a single level 1 trauma centre, who received either prehospital or ED tracheal intubation prior to initial whole-body CT from January 2008 to December 2019. Our objectives were to describe tube-to-carina distances (TCDs) via CT and to assess the risk factors and outcomes (mortality, length of intensive care unit stay and mechanical ventilation) of patients with endobronchial intubation (TCD <0 cm) using a multivariable model.

Results

We included 616 patients and discovered 26 (4.2%) cases of endobronchial intubation identified on CT. Factors associated with an increased risk of endobronchial intubations were short body height (OR per 1 cm increase 0.89; 95% CI 0.84 to 0.94; p≤0.001), a high body mass index (OR 1.14; 95% CI 1.04 to 1.25; p=0.005) and ED intubation (OR 3.62; 95% CI 1.39 to 8.90; p=0.006). Eight of 26 cases underwent tube thoracostomy, four of whom had no evidence of underlying chest injury on CT. There was no statistically significant difference in mortality or length of stay although the absolute number of endobronchial intubations was small.

Conclusions

Short body height and high body mass index were associated with endobronchial intubation. Before considering tube thoracostomy in intubated major trauma patients suspected of pneumothorax, the possibility of unrecognised endobronchial intubation should be considered.

The emergency department evaluation and management of massive hemoptysis

INTRODUCTION

Massive hemoptysis is a life-threatening emergency that requires rapid evaluation and management. Recognition of this deadly condition, knowledge of the initial resuscitation and diagnostic evaluation, and communication with consultants capable of definitive management are key to successful treatment.

OBJECTIVE

The objective of this narrative review is to provide an evidence-based review on the management of massive hemoptysis for the emergency clinician.

DISCUSSION

Rapid diagnosis and management of life-threatening hemoptysis is key to patient survival. The majority of cases arise from the bronchial arterial system, which is under systemic blood pressure. Initial management includes patient and airway stabilization, reversal of coagulopathy, and identification of the source of bleeding using computed tomography angiogram. Bronchial artery embolization with interventional radiology has become the mainstay of treatment; however, unstable patients may require advanced bronchoscopic procedures to treat or temporize while additional information and treatment can be directed at the underlying pathology.

CONCLUSION

Massive hemoptysis is a life-threatening condition that emergency clinicians must be prepared to manage. Emergency clinicians should focus their management on immediate resuscitation, airway preservation often including intubation and isolation of the non-bleeding lung, and coordination of definitive management with available consultants including interventional radiology, interventional pulmonology, and thoracic surgery.

Nasolaryngeal Distances in the Adult Population and an Evaluation of Commercially Available Nasotracheal Tubes

BACKGROUND

Preformed nasal endotracheal tubes (NETs) come with a predefined insertion depth due to their curved design. While size indication refers to internal diameter, there is a considerable variability in the corresponding lengths and proportions of same-sized tubes of different manufacturers which is probably based on the lack of data of nasolaryngeal distances (NLDs) in the adult population. Choosing the best-fitting NET is therefore difficult and carries the risk of endobronchial intubation or, on the contrary, cuff inflation at the vocal cord level. The aim of this study was to develop a prediction model for NLD and a selection guide to choose the appropriate NET based on a radiographic description of NLD in comparison to the measurements of available NETs of several manufacturers.

METHODS

After institutional ethics board review, 388 computed tomography (CT) scan images of head, neck, and upper thorax in a heterogeneous adult cohort were included. Mean distances from the nares to the lower border of the thyroid cartilage were measured. NETs from different manufacturers were measured and compared to the NLD derived from the radiographic analysis. The patients' sex, body height, and weight were considered as possible covariates in quantile regression models for predicting the NLD.

RESULTS

Data from 200 patients were analyzed. NLD was associated with sex, body height, and weight. A simple quantile regression model using the body height as the only covariate sufficed to achieve accurate predictions of NLD. Validation on independent test data showed that 92.8% of the NLD predictions were closer than ±20 mm to the observed NLD values. Measurements of equal-sized NETs varied considerably in outer diameter, proportion, the nasopharyngeal part, and guide marks. Length differences of the bend-to-cuff distance, containing the anatomically NLD, ranged between 218 and 270 mm at same sizes.

CONCLUSIONS

A reliable prediction of NLD can be obtained simply by body height, using the formula (Equation is included in full-text article.). As manufacturers' tube lengths vary substantially, additional information about the bend-to-cuff distance as corresponding tube section would allow for more accurate tube selection.

The Occurrence and Risk Factors of Inappropriately Deep Tip Position of Microcuff Pediatric Endotracheal Tube During PICU Stay: A Retrospective Cohort Pilot Study

OBJECTIVES

Cuffed endotracheal tubes are being used increasingly for pediatric patients on mechanical ventilation. Appropriate placement of the tube tip for Microcuff (Kimberley-Clark, Roswell, GA) pediatric endotracheal tube is guided by the intubation depth mark on the device. However, inappropriately deep tip position is sometimes observed during PICU stay. The purpose of this study was to assess the occurrence and risk factors of inappropriately deep tip position of Microcuff pediatric endotracheal tube during PICU stay.

DESIGN

A retrospective cohort study.

SETTING

The PICU at the National Center for Child Health and Development, one of the largest tertiary pediatric hospitals in Japan.

PATIENTS

All patients on mechanical ventilation with Microcuff pediatric endotracheal tube admitted between February 1, 2015, and July 31, 2016, were enrolled.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the occurrence of inappropriately deep tip position, defined as a position of the tube tip less than 5 mm above the carina on a chest radiograph. There were 179 cases (157 patients) requiring mechanical ventilation with Microcuff pediatric endotracheal tube during the study period. An inappropriately deep tip position was found in 42 cases (23.5%), including bronchial intubation in 13 cases (7.3%). In multivariate analysis, height in cm (odds ratio, 0.93; p < 0.001), history of abdominal disease or previous abdominal surgery (odds ratio, 4.38; p = 0.004), and oversized endotracheal tube (odds ratio, 2.93; p = 0.042) were found to be independent risk factors.

CONCLUSIONS

The occurrence of inappropriately deep tip position of Microcuff pediatric endotracheal tube during PICU stay was 23.5%. The possibility of an inappropriately deep tip position should be considered whenever patients with the above risk factors, a history of abdominal disease or previous abdominal surgery, and small children are treated or when oversized endotracheal tubes are used.