Teaching Clinical Competency: Evaluating POCUS‐Guided Versus Landmark Techniques for Thoracostomy Tube Placement in Canine Cadavers by Veterinary Students

ABSTRACT

Objective

To evaluate the effectiveness of teaching novice learners the competency of small‐bore wire‐guided thoracostomy tube (SBWGTT) placement using point‐of‐care ultrasound (POCUS)‐guided and blind, landmark‐guided techniques and assess the complications associated with each technique.

Design

Crossover randomized study.

Setting

Clinical skills teaching of second‐, third‐, and fourth‐year veterinary students.

Animals

Sixteen canine cadavers of various breeds, ages, and sexes.

Interventions

Thirty second, third and fourth‐year DVM students were enrolled. Online and in‐person training was completed before collection of cadaver data. Each student was randomized into two of four cadaver groups: POCUS‐guided (U) and landmark‐guided (L) protocols for either pleural effusion (PE) or pneumothorax (PN). Students placed SBWGTTs into canine cadavers with iatrogenic pleural space pathology (10 mL/kg of air and 10 mL/kg of fluid infused into each hemithorax); results were recorded.

Measurements and Main Results

Placement time, confidence in SBWGTT placement and ease of placement (using weighted scales), and complications (determined by necropsy) were recorded. Data were parametric. One SBWGTT was missing at necropsy. LPE SBWGTT placement (mean ± SD: 5.2 ± 1.1 min) was faster than UPE (7.9 ± 2.8 min, p = 0.0083) and UPN placement (9.0 ± 2.7 min, p = 0.0001). LPN placement (4.6 ± 1.6 min) was faster than UPN (p < 0.0001) and UPE placement (p = 0.0009). Eleven SBWGTTs were placed extrapleurally with no difference among groups. Four UPE SBWGTTs had intrathoracic complications, which were not different between groups (p > 0.05). Novices felt more confident that SBWGTTs were within the pleural space when using POCUS: UPN (mean ± SD: 7.2 ± 2.4) versus LPN (4.4 ± 2.6, p = 0.0232); LPE (4.6 ± 2.68) versus UPE (7.1 ± 2.9, p = 0.0326).

Conclusions

POCUS‐guided SBWGTT placement performed by novices was slower with similar complication rates and higher confidence scores.

Abbreviations

Calgary PLUS

Calgary Pleural Space and Lung Ultrasound

IP

in‐plane

LPE

landmark‐guided pleural effusion group

LPN

landmark‐guided pneumothorax group

OP

out‐of‐plane

PE

pleural effusion

PN

pneumothorax

POCUS

point‐of‐care ultrasound

PPV

positive pressure ventilation

SBWGTT

small‐bore wire‐guided thoracostomy tube

UPE

POCUS‐guided pleural effusion group

UPN

POCUS‐guided pneumothorax group

VAS

visual analog scale

1. Introduction

In small animal patients with pleural space disease, small‐bore wire‐guided thoracostomy tubes (SBWGTT) are routinely used for treatment of traumatic and spontaneous pneumothorax (PN) and pleural effusion (PE). As such, thoracostomy tube placement has been identified as a fundamental procedural skill that should be included in an emergency medicine–focused, competency‐based medical education framework [1]. A retrospective study of 156 cases revealed a complication rate of 32% in SBWGTT placements in dogs and cats, with most reported complications being technical and insertional in nature. Although most complications associated with thoracostomy tube insertion are minor, some are more serious, involving abdominal or thoracic injury, lung perforation, fistula formation, and vascular trauma, all of which are associated with increased morbidity and mortality [2, 3, 4]. Most serious complications go undetected unless severe clinical signs develop or are discovered on necropsy [3].

Risk factors for complications include multiple insertion attempts. In veterinary medicine, thoracostomy tube insertion currently relies on anatomic landmark‐based identification and blind percutaneous placement, regardless of the underlying pathology [5]. Use of ultrasound‐guided protocols would allow practitioners to visualize SBWGTT insertion directly into regions of pleural space disease. Although other thoracostomy tubes are used, such as trocar and red rubber catheters, SBWGTTs were used in the current study due to limitations with these other devices. Larger‐bore trocar types require general anesthesia and more training than SBWGTTs, and their use, in both human and veterinary patients, is associated with increased pain and complications, ranging from 44% to 58% in veterinary patients [6, 7, 8]. Reported complications in veterinary patients include vessel laceration, PN, lung puncture, pain, fluid leakage from the insertion site, and failure to drain due to tube malfunction. Additionally, large‐bore thoracostomy tubes are not amenable to point‐of‐care ultrasound (POCUS)‐guided technique insertion, given the need for subcutaneous tunneling and the creation of subcutaneous emphysema artifact [8, 9, 10].

Although many clinics have incorporated different ultrasound‐guided procedures, there is no standardized POCUS protocol available to help guide veterinarians through SBWGTT insertion. By contrast, ultrasound guidance is standard of care in human medicine for catheter insertion. In a simulation‐based study using a standardized human patient, emergency medicine residents were able to correctly identify the predetermined intercostal space (fourth or fifth) 48% of the time using palpation and 91% of the time using ultrasound guidance [11]. Emergency and critical care veterinary clinicians use POCUS for real‐time visualization of the catheter stylet tip during ultrasound‐guided centesis procedures, including cystocentesis, abdominocentesis, and potentially thoracocentesis. Additionally, the use of POCUS enables veterinarians to perform complex vascular access procedures, such as over‐the‐wire central catheter placement—a technique that also applies to thoracostomy tube insertion [12].

Traditionally, POCUS‐guided centesis techniques have been taught using an apprentice‐based approach (“see one, do one, teach one”) rather than a structured, competency‐based training framework. However, as more veterinary consortiums offer accelerated training pathways for emergency clinicians, the need for a structured approach to ultrasound‐guided procedures is increasing. In a fully ultrasound‐guided technique, the needle tip remains continuously visible, improving precision and safety compared with ultrasound‐assisted methods in which only the area of interest is visualized without direct needle tip identification.

The current study outlines a step‐by‐step approach in which novices are taught to implement a POCUS‐guided SBWGTT protocol for dogs with pleural space disease. Additionally, we aimed to compare POCUS‐guided SBWGTT placement with traditional blind landmark‐guided placement in terms of ease of placement, confidence, and complication rates. We hypothesized that POCUS‐guided placement would outperform blind landmark‐guided placement across all measures [11, 12].

2. Materials and Methods

2.1. Study Design and Participants

Second‐ and third‐year veterinary students from the University of Calgary Faculty of Veterinary Medicine were invited via email and an in‐person presentation to participate in this crossover randomized study. Animal and human ethics approval was obtained from the Veterinary Sciences Animal Care Committee (ACC Certificate: AC22‐0175) and the Conjoint Faculties Research Ethics Board (Ethics ID: REB23‐0255). Signed informed consent was obtained from all individual participants included in the study.

After signing consent, students were invited to complete an online Qualtrics¹ survey regarding participants’ self‐rated ultrasound skill level (Supporting Information S1). Participants reported their previous ultrasound experience by the number of scans they had performed previously (i.e., no skill: 0 scans, low skill: 1–3 scans, moderate skill: 4–11 scans, high skill: ≥11 scans). Two identical surveys were conducted, one before the initial online training modules (pre‐training) and another after completion of the online modules, in‐person training, and in‐person testing (post‐training). Participants used a 4‐point scale to self‐report their knowledge and confidence for the different steps used in SBWGTT insertions. The purpose of the survey was to assess participants’ perceived knowledge and confidence before and after educational training (Supporting Information S1 and S2).

After completing the survey, students were given shared online access to five online modules via commercial software², including the (1) modified Seldinger technique for SBWGTT insertion; (2) in‐plane (IP) and out‐of‐plane (OP) ultrasound technique for vascular procedures; (3) principles of pleural space disease; (4) SBWGTT insertion for PE; and (5) SBWGTT insertion for PN. Thorough instructions and visual aids on landmark‐ and ultrasound‐guided SBWGTT insertion protocols and how to apply them to pleural space disease in small animal patients were provided. Completion of a corresponding self‐assessment for each module was required using Typeform³ before moving on to the subsequent module. Students were given 1 month to complete online training.

Students progressed to in‐person, hands‐on training after completing the online training modules. Participants were divided into groups of 15 and received a total of 2 h of training using a chicken phantom vascular access model [13]. Both blind and IP/OP POCUS‐guided catheter⁴ insertion techniques were practiced on the chicken phantom vascular access model (Figure 1). This model was also used to introduce the modified Seldinger technique for SBWGTT⁵ insertion, with deliberate and guided feedback from two experienced Diplomates of the American College of Veterinary Emergency and Critical Care and one experienced student. One phantom chicken model was provided to every two students to practice on. After an instructor‐led demonstration of the technique, students were allowed to practice for up to 2 h or as long as they desired within that time frame. Three days after the chicken phantom vascular access training, students, in groups of 15, received 2 h of POCUS‐guided SBWGTT insertion training using a pork rib and bucket model [14] (Figure 2). This model was used to practice the complete modified Seldinger technique at the appropriate angle to simulate a real‐life SBWGTT insertion in a small animal with PE placed in sternal recumbency. Students were instructed to use a 45‐degree angle of insertion for both POCUS‐guided and landmark‐guided protocols and to account for estimation error in marking angles subjectively on the Objective Structured Clinical Examination. An ideal angle of insertion was described as between 30 and 60 degrees, and participants were assessed as either being within 30–60 degrees or not (Table 1).

FIGURE 1.

Chicken phantom point‐of‐care ultrasound vascular access practice model. (A) Demonstration of how the simulated vessels can be manually palpated. (B) Chicken phantom model used to introduce the modified Seldinger technique for catheter insertion. (C) Out‐of‐plane ultrasonographic image of chicken phantom vascular access model. (D) In‐plane ultrasonographic image of chicken phantom vascular access model. The italic legends represent the corresponding parts of the chicken vascular model; the normal font represents the sonoanatomy.

FIGURE 2.

Pork rib and bucket point‐of‐care ultrasound practice model. (A) Construction of the pork rib model includes a plastic zip‐top bag filled with water (representing parietal pleura and pleural effusion) and a sponge (representing visceral pleura and lung), with the overlaying pork rib (representing the chest wall with the ribs and intercostal muscles of a small animal) taped over an inverted bucket. (B) Final rendering of the pork rib with the ultrasound probe (placed in‐plane or long axis). (C) Out‐of‐plane (short axis) ultrasonographic image of the pork rib model, with labeling of the sonoanatomy. (D) In‐plane (long axis) ultrasonographic image of the pork rib model with labeling of the sonoanatomy.

TABLE 1.

Protocols for landmark‐guided and POCUS‐guided SBWGTT insertion in canine cadavers.

Landmark‐guided placement of SBWGTT

POCUS‐guided placement of SBWGTT

Participants will be randomly assigned to place an SBWGTT for either pleural effusion or pneumothorax. Place the patient in sternal recumbency. Clip the thorax between the third intercostal space to 13th intercostal space. Identify the seventh to eighth intercostal space and the costochondral junction. For pneumothoraces, nick the skin in the dorsal one‐third of the thorax. For pleural effusions, nick the skin in the ventral one‐third of the thorax below the costochondral junction. Insert the 14‐gauge over‐the‐needle introducer catheter into the pleural space (no tunneling is required). Remove the stylet and leave the catheter in place. J‐tip guide wire: Remove the tip cover by holding the guide wire at the thumb notch of the blue straightener. Using the thumb notch, retract the wire until the J is inside the straightener. Insert the straightener tip into the introducer catheter hub and advance the wire to the desired length (∼8–10 cm on average). Allow enough guide wire to remain outside the thorax such that the tip will protrude beyond the chest tube after it is placed. Remove the wire cover. Remove the introducer catheter from the guide wire while minimizing movement of the guide wire. Always hold on to the guide wire. Dilator: Feed the tip of the dilator catheter over the guide wire and advance the dilator catheter over the guide wire through the skin into the pleural space using a gentle pushing and twisting motion. Always hold on to the guide wire. Remove the dilator catheter once the skin and chest wall have been traversed and the dilator catheter has entered the pleural space. Remove the dilator catheter from the guide wire. Chest tube catheter: Feed the tip of the long‐term chest tube catheter over the guide wire and advance the catheter through the skin into the pleural space, using a gentle pushing and twisting motion. Always hold onto the guide wire. Once all catheter fenestrations are well seated within the pleural space, remove the guide wire from the long‐term chest tube catheter. Attach the needle‐free valve to the end of the catheter and evacuate the pleural space as needed with a syringe. This is a normally closed two‐way valve. Suture the wings of the long‐term chest tube catheter in place, one at the insertion site if the catheter is not advanced to the hub, and the second wing as a strain relief.

Participants will be randomly assigned to place an SBWGTT for either pleural effusion or pneumothorax, using either an OP or an IP insertion technique. Using the Calgary PLUS protocol, participants will identify pleural effusion or pneumothorax. Cadavers are intubated and undergoing positive pressure ventilation during the identification of pleural space disease and insertion of the catheter, to simulate lung sliding and identify lung points. Pleural effusion: The transition from pleural effusion to air‐filled lung in contact with the thoracic wall should be identified. The probe is then placed on the most ventral aspect of the visible pleural effusion, and the catheter with stylet, present in the SBWGTT kit, will be guided from the skin to the parietal surface using ultrasound guidance. The catheter and stylet tip will also be introduced into the pleural space under ultrasound guidance. After removing the catheter stylet, the student will slowly insert the guide wire, visualizing its advancement into the pleural effusion with ultrasound. Once the guide wire is advanced to the desired length, remove the wire cover. The next steps will be the same as the landmark‐guided SBWGTT placement (Steps 7–11). Pneumothorax: Participants will need to identify the absence of lung sliding in the caudodorsal region of the thorax and then identify the pneumothorax lung point by sliding the probe from a caudodorsal location to a cranial ventral location. The ultrasound probe will then be situated above the lung point and at least 1 cm below the dorsally located epaxial muscles. Using ultrasound guidance, the catheter/stylet tip will then be visualized as it traverses the soft tissues of the chest wall to the level of the parietal pleura, over a region where there is an absence of lung sliding. The catheter and stylet will no longer be visible as the catheter tip enters the region of pneumothorax (air reflects ultrasound waves), and the student will need to perform the rest of the SBWGTT procedure similar to that described for landmark placement. After advancing the catheter and stylet tip another 1–2 mm into the pleural space/pneumothorax, the SBWGTT should be placed as described in the landmark‐guided SBWGTT placement (Steps 4–11). During Steps 4–7, the ultrasound probe should be positioned at the level of the lung point below the insertion point to ensure the lung is not penetrated by the catheter (which will show up as a displacement of the lung surface on ultrasound). The remainder of the procedure will be the same as the landmark‐guided SBWGTT placement.

Abbreviations: POCUS, point‐of‐care ultrasound; SBWGTT, small‐bore wire‐guided thoracostomy tube.

Similarly, one pork rib model was provided for every two students to practice on. After an instructor‐led demonstration of the technique, students were allowed to practice for up to 2 h or as long as they desired within that time frame. The next day, students were randomly assigned to perform one anatomic landmark‐guided SBWGTT insertion and one ultrasound‐guided SBWGTT insertion on the same hemithorax of a positive pressure–ventilated cadaver. As a group (landmark vs. POCUS), students were randomized to perform one of these insertions for each of two already created pathologies, either PE or PN. Each ultrasound‐guided insertion was randomized to use either an IP or an OP technique (Figure 3). For example, Student 1 was randomized to landmark PN and a POCUS PE using the IP technique on the left hemithorax, and Student 2 was assigned to POCUS PN and landmark PE using the OP technique on the right hemithorax of Cadaver 1. Students were only allowed one attempt to place the SBWGTT for each assignment. Each student placed an SBWGTT every four placements. Results were recorded based on these tested insertions. All students were trained and tested using the same model of a commercial ultrasound machine⁶.

FIGURE 3.

Flow chart detailing the study's division of students into two of four cadaver groups: POCUS‐guided and landmark‐guided protocols for either pleural effusion or pneumothorax, with further POCUS‐guided subdivision into in‐plane or out‐of‐plane techniques. Each student was assigned to one landmark‐guided and one POCUS‐guided insertion. POCUS, point‐of‐care ultrasound.

In a previous study [1], the overall complication rate of SBWGTT insertions reported in small animals was 32% [2]. For power calculation, we aimed to decrease the complication rate to 15% using POCUS. To detect a power of 80% with an alpha set at 0.05 and a complication rate of 32% (landmark‐guided) versus 15% (POCUS‐guided), 51 SBWGTT attempts would be needed. A total of 60 SBWGTT insertions were performed for testing.

2.2. Canine Cadaver Model

Sixteen canine cadavers of various breeds, ages, and sexes were obtained from the anatomy service, frozen and thawed for use in all SBWGTT placement attempts (Supporting Information S3). No dog was euthanized for the purpose of the current study. Each cadaver was placed in sternal recumbency, had an endotracheal tube placed, and received positive pressure ventilation (PPV) using a commercially available manual resuscitator⁷. Each hemithorax was shaved, and alcohol was used as the coupling agent. Cadavers were scanned using the Calgary Pleural Space and Lung Ultrasound (Calgary PLUS) protocol to identify preexisting free fluid or air [15].

Using ultrasound guidance, an 18‐gauge, 1.5‐inch needle was advanced into preexisting PE (present cranioventrally secondary to the thawing process) to create pleural space pathology; 10 mL/kg of air followed by 10 mL/kg of fluid was then infused into each cadaver bilaterally. This created cadaver models with bilateral PE and PN. While cadaver dogs were receiving PPV, the Calgary PLUS POCUS protocol was repeated to assess the absence of glide sign caudodorsally, the lung point, and an abnormal curtain sign, which was used to confirm the presence of a PN. PE was confirmed by identification of anechoic fluid, tracking the diaphragm and filling the costophrenic recess at the pericardio‐diaphragmatic window, identifying the “sail sign” ventrally, and finding the sonographic point where PE and the PE lung point were visible in the same sonographic window. Cadavers were scanned again immediately before testing, and additional air and fluid were injected as needed to ensure obvious pleural space pathology.

2.3. Student POCUS‐Guided Identification of Pathology

Instructors (J.M., S.B., K.G., C.H.) assisted students in acquiring and interpreting POCUS images. Pneumothorax was identified using the Calgary PLUS protocol [15]. The probe was placed just caudal to the scapula at the junction of the middle and dorsal third of the thorax and slid caudally until the abdominal curtain sign was identified, which was assessed for asynchronous or double curtain signs. The probe was then swept dorsally along the abdominal curtain sign, watching for asynchronous or double curtain signs, until the caudal dorsal border of the PLUS protocol was visualized. Lung sliding was assessed at this caudal dorsal location. From the caudal dorsal border, the probe was slid cranially and ventrally toward the lung hilus (elbow of the dog) to locate the lung point. Instructors guided the novices in recognition of the various POCUS findings, given that POCUS identification was not the objective of the study. Students were instructed to insert the SBWGTT within a region of confirmed PN (Table 1).

Similarly, following the Calgary PLUS protocol, the probe was placed between the middle and ventral one‐third of the thorax to look for PE and slid caudally until the abdominal curtain sign was identified. The probe was then slid ventrally along the abdominal curtain sign toward the pericardio‐diaphragmatic window. PE was visualized as anechoic fluid. Given the large volume of effusion present, novices were not instructed or taught how to identify the pericardio‐diaphragmatic window or to rotate the probe parallel to the ribs to identify the sail sign.

After completion of the study, each cadaver had two SBWGTTs placed on each side of its chest, one ventral for PE and one dorsal for PN. Each SBWGTT per hemithorax was placed using a different technique (either landmark or ultrasound guided), and each cadaver had one landmark‐guided pneumothorax (LPN), one landmark‐guided pleural effusion (LPE), one POCUS‐guided pleural effusion (UPE), and one POCUS‐guided pneumothorax (UPN). Students were assessed in real time by the same individuals performing the training (two instructors and two experienced students) on the following points during SBWGTT insertion: adherence to protocol, in which a skill scoring sheet was used to assess if students adequately adhered to the assigned protocol (Table 2); successful placement, defined as a thoracostomy tube placed within the pleural space that could aspirate at least 3 mL of air or fluid, regardless of the assigned pathology for that placement; and time to placement, defined as the time from which the student began palpating (for landmark approach) or scanning (for ultrasound approach) until the thoracostomy tube was placed and aspirated for air or fluid to confirm patency. Time was recorded in minutes.

TABLE 2.

Skill scoring sheet for assessment of adherence to protocol for landmark‐guided and POCUS‐guided SBWGTT insertion in canine cadavers.

Procedure step	Grade	Achieved	Comment
Premeasure the length of chest tube required for insertion From: expected location of insertion To: caudal axillary region	1		Length: _______cm
Identify the appropriate insertion location on the cadaver for given pathology: Pneumothorax: Eighth to ninth ICS at or above the two‐thirds mark on the chest wall Pleural effusion: Seventh to eighth ICS at the one‐third mark on the chest wall	1
Insert the introducer catheter over the needle/stylet into the pleural space at a 45‐degree angle, making sure not to back the needle/stylet out while advancing the catheter	2		Angle: _____
Remove the needle/stylet, leaving the catheter in place	1
Insert J‐tip guide wire and advance the desired amount (5–10 cm)	1
Keep one hand on the guide wire throughout the next three steps	3
Pull the introducer catheter off over the wire, leaving the wire in place	1
Feed the dilator over the wire, pushing/twisting through skin into the pleural space, and remove once the pleural space is penetrated	1
Feed the chest tube catheter over the wire and advance the catheter through the skin into the pleural space	1
All fenestrations on chest tube catheter are well into the pleural space	1
Adhere to premeasured length of chest tube	1
Remove J‐tip guide wire	1
Clamp chest tube catheter closed	1
Demonstrate chest tube patency by removing 3 mL of air/fluid	2

Abbreviations: ICS, intercostal space; POCUS, point‐of‐care ultrasound; SBWGTT, small‐bore wire‐guided thoracostomy tube.

Students were asked to complete a visual analog scale (VAS; Supporting Information S4). The scale (measuring 0–10 cm) was distributed to each participant immediately after their SBWGTT insertion attempt to assess confidence in placement of the SBWGTT within the pleural space (0 = unsure of SBWGTT placement within the thorax and 10 = very confident of SBWGTT placement); ease of placement using the modified Seldinger technique; and ease of placement using the assigned ultrasound technique (OP or IP, if applicable; 0 = extremely difficult and 10 = very easy).

Each cadaver underwent necropsy the next day. First, a skin incision was made at the insertion of the SBWGTT and along the SBWGTT, following its path from the skin into the pleural space or until the end of the SBWGTT was identified. Second, an incision was made caudal to the last rib, entering the abdominal cavity, and the diaphragm was assessed for integrity (presence of a dome shape) and evidence of perforation. Results for diaphragm integrity were recorded. A 10‐cm incision was then made along the diaphragm to enter the pleural space. The pleural cavity was assessed to visualize the presence of the SBWGTT. Each tube was recorded as being present or absent within the pleural space. Third, to avoid disrupting placement of the SBWGTT before assessment of intrathoracic complications, the ribs were removed en bloc by cutting them with bone rongeurs along the costochondral junction ventrally and near the rib insertion dorsally. After removal of the rib flap, intrathoracic complications (lung surface penetration) were assessed and recorded. Complications defined as any abnormal placement of the SBWGTT (outside the pleural space or within the lung parenchyma) were also recorded.

2.4. Statistical Methods

Data were assessed for normality using the D'Agostino–Pearson test or the Shapiro–Wilk test in cases where the number of values was insufficient to use the D'Agostino–Pearson test. Continuous data were grouped and organized into scatterplots to identify potential outliers. The ROUT method with a maximum desired false discovery rate (Q) of 1% was used to confirm and remove outliers. Parametric data are reported as mean ± SD, while nonparametric data are reported as median and range. One‐way ANOVA with Tukey multiple comparisons was used after the SBWGTT survey for VAS analysis. The angle of insertion was categorized as correct if between 30 and 60 degrees and was assigned a value of 0. If the insertion angle was less than 30 degrees, it was classified as incorrect and assigned a value of 1. If the insertion angle was more than 60 degrees, it was classified as incorrect and assigned a value of 2 (Figure 4). Categorical data were organized into contingency tables and compared using Fisher's exact test. The pre‐training and post‐training phase surveys yielded paired ordinal categorical variables for each participant. Each variable was assigned a discrete numerical value from 1 to 4 to describe the least to most knowledge or confidence. All data were analyzed using the Wilcoxon matched‐pairs signed‐rank test with the Pratt method for ties. Correlation was determined using Pearson's correlation test. An alpha level of 0.05 was set for all data. Statistical analysis was performed with commercial software⁸.

FIGURE 4.

Ideal angle of SBWGTT catheter insertion showing the ultrasound probe; the same angles are used for the landmark technique. (A) Ideal angle of insertion: between 30 and 60 degrees from the skin surface. (B) A 90‐degree angle for catheter insertion makes it challenging to visualize when ultrasound techniques are used. (C) Insertion at less than a 30‐degree angle may cause advancement within the intercostal muscles, regardless of the technique used, especially in round‐chested dogs. Additionally, if using ultrasound, despite appearing at the pleural line, advancement into the pleural space may be challenging. SBWGTT, small‐bore wire‐guided thoracostomy tube.

3. Results

Thirty‐two second‐ and third‐year students were recruited via email and signed the consent form. Two students were unable to complete the online module training and elected to withdraw from the study. One student was unable to complete the in‐person training and elected to withdraw from the study. One fourth‐year veterinary student who was also a novice on ultrasound and familiar with the study volunteered to participate. That veterinary student did not complete the online module training but participated in the in‐person training and testing. In total, 30 veterinary students (22 second‐year, seven third‐year, and one fourth‐year) completed the study.

3.1. Participants’ Self‐Rated Ultrasound Skill Level Before Training

Students with a low skill level at performing ultrasound (20/29 [69.0%]) outnumbered those of all other categories combined, including students with no skill level (1/29 [3.4%]), moderate skill level (7/29 [24.0%]), and high skill level (1/29 [3.4%]).

3.2. Adherence to Protocol Skill Scoring Sheet

No significant difference was found among the four groups in adherence to protocol as determined by the skill scoring sheet. The mean percentage score for each group was >85%: LPE, 88.5% (±9.5); LPN, 86.7% (±11.3); UPE, 91.1% (±7.4); and UPN, 88.2% (±13.4).

3.3. Successful Placement

Overall, 38 of 60 (63%) SBWGTT insertions in the current study were successful, with 16 (53%) being landmark ‐guided and 22 (73%) being POCUS ‐guided. There was no difference in successful placement between groups (LPE, LPN, UPE, UPN). However, POCUS‐guided insertion for pneumothorax (UPN) tended to be more successful, with 12 of 15 (80%) placements having positive aspiration of 3 mL of air compared with UPE (10/15 [66.7%], Fisher's exact test; p = 0.68), LPN (9/15 [60%], Fisher's exact test; p = 0.43), and LPE (7/15 [46.7%], Fisher's exact test; p = 0.13).

3.4. Time to Placement

Landmark‐guided insertions of SBWGTTs were faster than POCUS‐guided insertions (Figure 5), with LPE placements (mean ± SD: 5.2 ± 1.1 min) faster than UPE (7.9 ± 2.8 min, p = 0.0083) and UPN (9.0 ± 2.7 min, p = 0.0001) and LPN (4.6 ± 1.6 min) placements faster than UPN (p < 0.0001) and UPE (p = 0.0009).

FIGURE 5.

Scatter plot showing distribution of times to placement between SBWGTT insertion attempts into canine cadavers for the four different groups tested: (1) LPE, (2) LPN, (3) UPE, and (4) UPN. **p = 0.0083; ***p ≤ 0.001; ****p = 0.0009. LPE, landmark‐guided pleural effusion; LPN, landmark‐guided pneumothorax; SBWGTT, small‐bore wire‐guided thoracostomy tube; UPE, ultrasound‐guided pleural effusion; UPN, ultrasound‐guided pneumothorax.

3.5. Angle of Insertion

More POCUS‐guided placements (26/30 [86.7%]) were made at the appropriate angle of insertion than landmark‐guided (16/30 [53.3%]). There were more landmark‐guided attempts inserted outside of 30–60 degrees, with most of the incorrectly angled LPN attempts made at 90 degrees. More UPE SBWGTTs (14/15 [93.3%]) were placed between 30 and 60 degrees compared with LPN (6/15 [40%], Fisher's exact test; p = 0.0052). No differences were observed between the number of tubes placed between 30 and 60 degrees for LPE (10/15 [66.7%]) or UPN (12/15 [80%]).

3.6. Complications

One SBWGTT was missing on necropsy and could not be assessed for complications. Complications occurred in 14 of 59 (23.7%) SBWGTT placement attempts. Complications occurred in six of 30 (20%) landmark‐guided SBWGTT placements and in eight of 29 (27.6%) POCUS‐guided placements, with no statistically significant difference between groups. Eleven SBWGTTs were placed outside the pleural space (extrathoracic complications), including three LPN, three LPE, one UPE, and four UPN. There was no significant difference between groups. Extrathoracic complications comprised SBWGTTs buried in subcutaneous fat or buried into epaxial or intercostal musculature and one tube that slid out of the chest wall completely (Figure 6). Intrathoracic complications were seen in four UPE SBWGTTs, including one retained broken guide wire, two lung penetrations, and one tube placed <1 cm into the pleural space (Figure 7). There was a weak to moderate, positive correlation between the time it took to complete the procedure and the presence of complications (Pearson's correlation coefficient: 0.45; p = 0.0012). There was no difference in the angle of insertion (<30 degrees, between 30 and 60 degrees, and >60 degrees) and placement within the pleural space (Fisher's exact test; p = 0.42).

FIGURE 6.

Extrathoracic complications of SBWGTT insertion in canine cadavers. (A, B) Subcutaneous fat. (C) Epaxial musculature. (D) Intercostal musculature. (E) SBWGTT outside the chest wall. SBWGTT, small‐bore wire‐guided thoracostomy tube.

FIGURE 7.

Intrathoracic complications of SBWGTT insertion in canine cadavers. (A) Retained and bent guide wire within the pleural space and SBWGTT in the intercostal muscles. (B) Retained and bent guide wire stuck within the SBWGTT. SBWGTT, small‐bore wire‐guided thoracostomy tube.

3.7. Visual Analog Scale

Students felt more confident that the SBWGTT was correctly placed within the pleural space when using POCUS‐guided techniques compared with the landmark technique (Figure 8A). Specifically, confidence scores were higher for UPN (mean: 7.2 ± 2.4) compared with LPN (4.4 ± 2.6, p = 0.0232) and LPE (4.6 ± 2.7, p = 0.0422). Similarly, confidence with UPE (7.1 ± 2.9) was significantly higher than with LPN (p = 0.03). However, there was no significant difference in confidence between UPE and LPE (p = 0.06). Using POCUS did not make the modified Seldinger technique easier to perform (Figure 8B). Additionally, students did not show a preference for the IP technique over the OP technique when using POCUS, regardless of the underlying pathology (Figure 8C).

FIGURE 8.

VAS scatterplots with distribution of data from 30 veterinary students attempting to place SBWGTT into canine cadavers after a standardized training program. (A) Confidence in placement within the pleural space. (B) Ease of placement using the modified Seldinger technique. (C) Ease of placement using IP and OP ultrasound. *p < 0.05. IP, in‐plane; LPE, landmark‐guided pleural effusion; LPN, landark‐guided pneumothorax; OP, out‐of‐plane; SBWGTT, small‐bore wire‐guided thoracostomy tube; UPE: ultrasound‐guided pleural effusion; UPN: ultrasound‐guided pneumothorax; VAS, visual analog scale.

3.8. Pre‐training and Post‐training Phase Surveys

Students had a significant increase in perceived knowledge of the modified Seldinger technique, self‐reported as minimal knowledge pre‐training (median: 2, interquartile range [IQR]: 1–2) to knowledgeable post‐training (median: 3, IQR: 3–4; p ≤ 0.0001). Confidence in the procedural skill placement of an SBWGTT also improved after training, from somewhat confident (median: 2, IQR: 1–2) to very confident (median: 4, IQR: 3–4; p < 0.0001). Self‐reported confidence in locating the site for insertion of an SBWGTT using the landmark technique improved from somewhat confident (median: 2, IQR: 2‐2) to confident (median: 3, IQR: 2–3; p = 0.0002). Self‐reported confidence in locating the site for insertion of an SBWGTT using POCUS improved from not confident (median: 1, IQR: 1–2) to confident (median: 3, IQR: 3–4; p < 0.0001). Self‐reported confidence in diagnosing PE using POCUS improved from not confident (median: 1, IQR: 1–2) to very confident (median: 4, IQR: 3–4; p < 0.0001). Self‐reported confidence in diagnosing PN using POCUS improved from not confident (median: 1, IQR: 1–2) to confident (median: 3, IQR: 2–3; p < 0.0001) (Figure 9).

FIGURE 9.

Perceived knowledge and confidence scores of 30 veterinary students before and after a standardized training program for point‐of‐care ultrasound‐guided SBWGTT placement. Knowledge scores: 1: no knowledge; 2: minimal knowledge; 3: knowledgeable; 4: very knowledgeable. Confidence scores: 1: not confident; 2: somewhat confident; 3: confident; 4: very confident. ***p = 0.0002; ****p < 0.0001. LM, landmark palpation technique; PE, pleural effusion; PN, pneumothorax; SBWGTT, small‐bore wire‐guided thoracostomy tube; US, ultrasound.

4. Discussion

Compared with blind landmark‐guided placement, novice‐performed POCUS‐guided SBWGTT placement was characterized by a slower pace, similar complication rates, and higher confidence scores. These findings are contradictory to our hypothesis, in which the complication rate would be lower with POCUS‐guided SBWGTT placement compared with landmark (blinded) SBWGTT placement. This outcome was unexpected, as we initially hypothesized that POCUS‐guided placement would yield success rates comparable to those reported in people by emergency room doctors (91%) [11]. This disparity may be explained by differences in overall experience between participants. Veterinary students had limited previous exposure to POCUS, catheter placement, and POCUS‐guided centesis techniques, whereas emergency room doctors had additional clinical and procedural experience. Furthermore, inadequate training with canine cadavers and difficulties in translating skills from POCUS‐guided models to real cadaveric settings may have influenced the results.

The current training techniques were developed based on our institution's clinical skills curriculum. During their clinical skills course a few months before the study began, second‐year veterinary students were taught to place landmark‐guided SBWGTTs in cadavers. Therefore, we assumed that students had already acquired proficiency in landmark‐guided SBWGTT insertion. The online modules and self‐assessment quiz were designed to address concepts and knowledge not yet covered in the second‐year curriculum, as well as to revisit landmark‐guided pleural and PN SBWGTT insertions before hands‐on training. As such, for the purpose of the training module, the following knowledge gaps were identified as essential: the modified Seldinger technique, IP and OP vascular access insertion techniques, pleural space diseases in general, and the use of POCUS for SBWGTT placement in cases of PN and PE. A strong emphasis was placed on mastering POCUS‐guided centesis techniques in the hands‐on portion of the training program, with particular focus on the coordination required for needle insertion. Participants used the chicken vascular model to hone this skill, concentrating on scanning in the horizontal plane and practicing both IP and OP vascular access techniques. The chicken vascular model was selected because it is a simple, inexpensive, and highly realistic phantom model for ultrasound‐guided vascular access training. The fluid‐filled modeling balloon can be swapped out after numerous punctures, allowing unlimited practice during training sessions. This model was chosen to help novices develop essential skills, including hand–eye coordination for needle insertion and ultrasound image interpretation, probe manipulation, and orientation. Additionally, it aids in understanding the three‐dimensional relationship between the phantom, needle placement and advancement, and the ultrasound image. The primary limitation of this model is that procedures are performed exclusively on a horizontal plane.

Recognizing that dogs and cats in respiratory distress often assume a standing or sternal position, we aimed to transition the acquired needle/probe positioning skills from the horizontal plane on which the chicken vascular model was practiced to the vertical plane, using the pork rib model. The pork rib model was chosen because it mimics a dog's chest and has been used previously by trainees for simulating POCUS PE and practicing thoracocentesis [14]. However, it is important to note that the pork rib model has limitations, particularly in simulating PN.

One of the limitations pointed out by the students during the exit survey was the inability to practice both POCUS‐guided and landmark‐guided SBWGTTs for PE and PN in canine cadavers before assessment. Using canine cadavers for teaching and training purposes, especially for large student cohorts, presents numerous logistical challenges, including sourcing, preparation, and ethical considerations. Prolonged preservation of canine cadavers through vascular injection of a modified Larson solution shortly after death has been described as a useful model for surgical skills training [16]. This approach may offer an appealing alternative to frozen‐thawed cadavers; however, its fidelity for teaching procedures guided by POCUS, such as the placement of SBWGTTs, remains uncertain. Specifically, it is unknown whether the preserved cadaver can support the PPV necessary to replicate ultrasound findings characteristic of PE or PN. Additionally, the impact of repeated SBWGTT placements on model reliability is unclear, as the development of subcutaneous edema or seroma over time may compromise ultrasound image quality and diminish the cadaver's usefulness as a teaching tool. Despite these challenges, we hoped that the cost‐effective and self‐made POCUS models would be sufficient to effectively teach novices this skill. Overall, the training module demonstrated good skill acquisition, with adherence to the protocol exceeding 85%.

Simulation‐based training has demonstrated effectiveness in teaching clinical skills to healthcare professionals, including veterinary students [17, 18]. Notably, simulation‐based ultrasound‐guided training of thoracocentesis has been shown to reduce complication rates, most notably PN, in specific medical training programs [19].

Despite an overall good skill acquisition, approximately one‐fourth of SBWGTT placements had complications. This demonstrates that despite following specific, clearly defined steps, complications were still possible, and the tools used to assess mastery of procedural skills do not predict complication rate. Complications were evaluated through gross necropsy, enabling the detection of major complications, as described in the previous study on SBWGTT complications. However, minor complications, such as pleural irritation or microperforations, may have been undetectable through gross examination. Complications were observed in both POCUS‐guided and landmark‐guided SBWGTT placements, with intrathoracic complications exclusively occurring in the UPE group. It is important to highlight that fewer landmark‐guided placements entered the pleural space, as many were inadvertently inserted subcutaneously. Consequently, the likelihood of intrathoracic complications from these placements decreased. The majority of extrathoracic complications (i.e., subcutaneous placement of the SBWGTT) were attributed to landmark‐guided insertions, suggesting that a lack of visualization of the pleural space during insertion hampers the ability of novices to accurately place SBWGTTs for pleural space pathology. Because each hemithorax underwent both landmark‐guided and POCUS‐guided SBWGTT placement, it is unlikely that chest conformation or body condition score influenced placement success. Body fat is expected to be evenly distributed across the thorax, minimizing its impact. Furthermore, the crossover design, in which each cadaver's hemithorax received a different technique (landmark or ultrasound) for each pathology, helped mitigate potential effects of chest conformation.

All intrathoracic complications occurred during UPE SBWGTT placement. In cases of PE, students should have been able to visualize the needle tip and its advancement into the PE using ultrasound guidance and, subsequently, advancement of the guide wire through the catheter and into the pleural space, thereby minimizing the risk of lung impalement. A possible explanation is that, as the dog was positioned in sternal recumbency, both the probe and the thoracostomy tube insertion site were located close to the sternum, which may have impaired motor skills, thus increasing the risk of complications. Given there was no difference in complication rates between the landmark‐guided and POCUS‐guided groups, it is possible that the POCUS group was using ultrasound assistance, and not ultrasound guidance, to place SBWGTTs. With ultrasound assistance, the operator identifies the correct area to place the catheter but does not visualize the catheter and stylet tip. With more experienced clinicians performing the procedure, it is possible that the technique would more likely be ultrasound guided rather than ultrasound assisted. This is because experienced clinicians may have a faster mastery of the IP and OP POCUS‐guided needle insertion and centesis techniques, particularly if they have POCUS experience in other guided interventions. Last, it is possible that there was some inter‐student variability in the ultrasonographic interpretation of images. To minimize variability that might have occurred due to operator experience in identifying sonoanatomy, instructors guided students on the correct sonographic area to locate pathology (size and location of the PN, size and location of the PE) but did not give specific guidance regarding the visualization of the pleural line, rib shadow, or intercostal muscles. Some students could have misinterpreted these findings, which may subsequently have influenced the results. In the hands of more experienced clinicians, it is possible that the technique described here was ultrasound guided rather than ultrasound assisted, as experienced clinicians may have a faster mastery of the IP and OP POCUS‐guided needle insertion and centesis technique.

Interestingly, complications were not correlated with the angle of insertion. Novices in the landmark group tended to insert the catheter at angles greater than 45 degrees, potentially leading to issues such as difficulty in discerning loss of resistance when traversing the pleura and inadvertent catheter placement in subcutaneous tissue or lung parenchyma. In the POCUS group, angles between 30 and 60 degrees were commonly observed. However, it is possible that despite having the “ideal” angle, some catheters may have been too short in round‐chested dogs or dogs with high body condition scores to sufficiently enter the pleural space to allow successful placement of the guide wire. If catheter tips were minimally advanced into the pleural space, it is possible they may have been dislodged to the subcutaneous tissues during guidewire passage, subsequently resulting in accidental insertion of the SBWGTT within the subcutaneous fat, rather than into the pleural space. Studies in human emergency trauma patients have shown that greater insertion angles (>45 degrees) are associated with a higher number of complications [12], suggesting the need for similar investigations in small animal patients, particularly overweight round‐chested dogs, to refine protocols.

Each novice was only allowed one attempt per SBWGTT. POCUS‐guided SBWGTT placements were significantly slower compared with landmark‐guided placements. This finding is not surprising, as there were a larger number of steps in the POCUS protocol. Identification of the catheter stylet tip on ultrasound may lead novices to pause to maximize their image acquisition. Studies in simulation training have shown that students who have undergone simulation may have taken longer to achieve the task but have better end results compared with those who did not undergo specific simulation training. Speed is less essential than outcome.

Our study showed a weak to moderate correlation between time and complication, suggesting that longer insertion time could lead to complications. In the POCUS group, novices may have taken longer to achieve the task if they had issues identifying the needle on POCUS. Although a few minutes of reduced procedure time may seem significant in agonal or distressed patients, in practice, critical patients with pleural space disease are often stabilized with thoracocentesis before placement of an SBWGTT. As a result, the time difference between techniques is unlikely to be clinically relevant. It is also possible that with increased POCUS training and practice in placing SBWGTTs, the time delay observed between landmark‐guided and POCUS‐guided placement in novices could be decreased. A comparison of experts’ and novices’ time to placement was not assessed in the current study but would be interesting to investigate in future studies.

Students performed both POCUS‐guided and landmark‐guided SBWGTT placements with similar self‐recorded ease but were significantly more confident when using POCUS that the SBWGTT was correctly placed within the pleural space. We expected novices to feel more confident with placement using POCUS because it helps confirm that the catheter is inserted within the pleural space, rather than the abdomen or subcutaneously. Additionally, there was a potential bias, given that instructors aided students in the identification of the pathology with POCUS. Last, if used correctly, POCUS may also help identify the needle tip and guide wire within PE rather than the subcutaneous tissue.

Where the diaphragm is located in relation to the ribs and costophrenic recess varies depending on a breed's anatomy, as the angles of the chest walls differ. Body condition can change the distance into which a catheter must be inserted to reach the pleural space. POCUS allows visualization of the diaphragm when pleural fluid is present and can be used to measure the distance between the visceral and parietal pleura, presenting options for a more precise SBWGTT placement in case of PE.

Our findings align with the very limited literature on the relationship between training and confidence. A small retrospective study investigating tracheal intubation by medical students demonstrated that satisfaction with performance improved with repeated practice but declined significantly when intubation attempts failed, when multiple attempts were needed, or when complications arose. Similarly, students’ confidence in their ability to perform future intubations increased with the number of successful procedures but diminished in the face of repeated attempts, failures, and complications [20]. Although technology‐enhanced simulation training has consistently shown positive effects on knowledge, time management, process, and final product compared with no training, its direct impact on patient outcomes remains modest yet meaningful [21]. Importantly, it remains largely unexamined whether gains in learner confidence after simulation translate into improved clinical outcomes and reduced complications in veterinary patients [22].

On average, students using the OP technique for POCUS‐guided SBWGTT insertion had lower ease of placement scores on VAS, suggesting they experienced more difficulties using this technique compared with the IP technique. This may be influenced by a previous experience bias of the novices. Novices in the current study have likely observed or performed cystocentesis, which uses the IP technique. The ability to visualize the entire needle during the procedure, rather than just the tip as in the OP technique, may have further boosted novice confidence. Notably, novices found the OP technique particularly challenging in cases of PN. This difficulty may stem from the fact that, once the needle enters the pleural space, its tip is no longer visible. In contrast, when using the IP technique for PN, students can still see the remainder of the needle within the soft tissues of the thoracic wall, providing confidence that the nonvisible section of the needle is positioned within the pleural space (Figure 9).

After being trained and tested, students felt significantly more knowledgeable about how to place an SBWGTT and the modified Seldinger technique, and more confident in recognition of PE and PN on ultrasound (Figure 8). One limitation of this study is the assumption that students had little to no previous experience with the modified Seldinger technique, SBWGTT placement, and insertion of peripheral catheters. Variations in individual exposure and self‐reported confidence in these skills may have introduced bias. Interestingly, the least significant improvement was seen with their confidence in locating a site for insertion using a landmark‐guided approach. The in‐person training sessions lacked available cadavers for practicing landmark‐guided placement, which consequently could lead students to feel less confident in their palpation skills and identification of anatomic landmarks.

Conversely, a large amount of hands‐on training was spent practicing POCUS‐guided insertion, especially with PE pathology, because of the use of the pork rib and bucket model. We did see the largest improvement in median scores and IQR for confidence in diagnosing PE on POCUS, likely due to the emphasis placed on this pathology in training. Given the reported tactile learning nature of most of our study cohort, the time spent with hands‐on practice of each SBWGTT placement approach likely influenced their confidence as one would expect—greater confidence with greater time spent practicing. The absence of a sonographic PN model may have introduced bias into our results. Developing a realistic sonographic model to simulate PN would be highly valuable for POCUS pathology recognition and procedural skills training.

The post‐training phase survey engaged the students in discussion about the most and least effective aspects of the training sessions. Consensus among students indicated the most helpful elements of training were the time spent with hands‐on ultrasound use, the depth of material covered during training and continued access to summarized material in the form of a laboratory manual, the repetition of material between the videos and the training sessions, and the chicken vascular access model. The most notable deficiency in training was the lack of a simulated PN model to practice POCUS identification and POCUS‐guided SBWGTT insertion with this pathology. This issue was compounded by not being able to practice on cadavers with simulated pathology due to resource and financial constraints. Students also expressed that more cadaver practice would have improved their ability to identify the appropriate sites for insertion. The poor durability of the pork rib model was another source of trouble among the students because, due to leakage, the plastic bag had to be replaced often. Additionally, if layers of a water‐filled plastic bag and pork rib were not correctly assembled on the model of PE, visualization with the ultrasound machine was poor.

This study had several limitations, with the most significant being the subjective assessment of the training model's efficacy. The pre‐ and post‐training phase surveys provided a perceived value in training by the students through the knowledge and confidence scoring; however, the students did not perform any recorded SBWGTT placements before training that would have provided a baseline for objective comparison. However, all techniques evaluated had an average skill score >85%, which indicates good clinical skill performance. The discrepancy between the significantly increased self‐reported confidence with POCUS after training and the absence of a difference in successful POCUS‐guided placements and similar complications strongly supports this possibility.

Second, the study may have suffered from a lack of power. The initial power analysis, based on Boullhesen Williams et al. [2], indicated that 51 attempts were sufficient for assessing complication rates. The cited study was performed by house officers and not novices; however, POCUS‐guided SBWGTT insertion was not described in the study. It is possible that the small sample size of the current study resulted in a type II error and a failure to detect a difference between the two groups. Based on post hoc power analysis of the results obtained, we calculated that 78 attempts would be required in order to detect a difference in complication between the two techniques. Additionally, the cadaver models were manually ventilated throughout the testing, which may have increased the volume of the PN and enabled easier identification of the insertion site. As PPV was not standardized between cadavers, it is possible that the degree of lung expansion and PPV parameters could have affected the findings. Many SBWGTT placements for PE in these cadavers consequently retrieved a combination of air/fluid or only air, instead of only fluid, upon aspiration due to the large pneumothoraces present, despite obvious insertion of the catheter into a pocket of fluid. Availability of more cadavers would have allowed simulation of a single type of pathology on each side of the thorax and a more accurate analysis of success rate between groups.

Furthermore, although cadaver models are practical for training purposes, they do not fully replicate the tissue characteristics and dynamic physiology of live patients, including spontaneous breathing—especially in patients with respiratory disease, lung expansion, and pleural adhesions. Therefore, further studies in live dogs are needed to determine whether these findings can be replicated in a clinical setting.

In the current study, novices were successfully taught the POCUS‐guided SBWGTT technique, demonstrating that the protocol can be taught even to those with limited previous experience. However, in the hands of novices, POCUS‐guided placement was slower and did not reduce complication rates compared with the blind landmark technique, despite increasing student confidence. These findings suggest that while the technique is feasible for beginners, its full potential may only be realized with more advanced training. Further studies are warranted to evaluate whether dedicated POCUS training that focuses on needle visualization and guidance results in experienced clinicians performing POCUS‐guided SBWGTT placement with greater speed and fewer complications.

Disclosure

Partial results of this study were presented as an oral presentation at the EVECC Congress 2024 in Gothenburg, Sweden. All SBWGTT kits used in this study were donated by MILA International.

Ethics Statement

The authors confirm that the ethical policies of the Journal have been adhered to, and appropriate ethical review committee approval has been received. This project was approved by the Veterinary Sciences Animal Care Committee (VSACC) (ACC Certificate: AC22‐0175) and the Conjoint Faculties Research Ethics Board (CFREB) (Ethics ID: REB23‐0255) for animal and human ethics, respectively. Informed consent was obtained from all individual participants included in the study.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Supporting File 1: vec70118‐sup‐0001‐SuppMat.Docx

Data Availability Statement

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.