Medical resuscitations in rugged prehospital settings require emergency personnel to perform high-risk procedures in low-resource conditions. Just-in-Time Guidance (JITG) utilizing augmented reality (AR) guidance may be a solution. There is little literature on the utility of AR-mediated JITG tools for facilitating the performance of emergent field care.

The objective of this study was to investigate the feasibility and efficacy of a novel AR-mediated JITG tool for emergency field procedures.

Emergency medical technician-basic (EMT-B) and paramedic cohorts were randomized to either video training (control) or JITG-AR guidance (intervention) groups for performing bag-valve-mask (BVM) ventilation, intraosseous (IO) line placement, and needle-decompression (Needle-d) in a medium-fidelity simulation environment. For the interventional condition, subjects used an AR technology platform to perform the tasks. The primary outcome was participant task performance; the secondary outcomes were participant-reported acceptability. Participant task score, task time, and acceptability ratings were reported descriptively and compared between the control and intervention groups using chi-square analysis for binary variables and unpaired t-testing for continuous variables.

Sixty participants were enrolled (mean age 34.8 years; 72% male). In the EMT-B cohort, there was no difference in average task performance score between the control and JITG groups for the BVM and IO tasks; however, the control group had higher performance scores for the Needle-d task (mean score difference 22%; P = .01). In the paramedic cohort, there was no difference in performance scores between the control and JITG group for the BVM and Needle-d tasks, but the control group had higher task scores for the IO task (mean score difference 23%; P = .01). For all task and participant types, the control group performed tasks more quickly than in the JITG group. There was no difference in participant usability or usefulness ratings between the JITG or control conditions for any of the tasks, although paramedics reported they were less likely to use the JITG equipment again (mean difference 1.96 rating points; P = .02).

This study demonstrated preliminary evidence that AR-mediated guidance for emergency medical procedures is feasible and acceptable. These observations, coupled with AR’s promise for real-time interaction and on-going technological advancements, suggest the potential for this modality in training and practice that justifies future investigation.

Cricothyrotomy and chest needle decompression (NDC) have a high failure and complication rate. This article sought to determine whether paramedics can correctly identify the anatomical landmarks for cricothyrotomy and chest NDC.

A prospective study using human models was performed. Paramedics were partnered and requested to identify the location for cricothyrotomy and chest NDC (both mid-clavicular and anterior axillary sites) on each other. A board-certified or board-eligible emergency medicine physician timed the process and confirmed location accuracy. All data were collected de-identified. Descriptive analysis was performed on continuous data; chi-square was used for categorical data.

A total of 69 participants were recruited, with one excluded for incomplete data. The paramedics had a range of six to 38 (median 14) years of experience. There were 28 medical training officers (MTOs) and 41 field paramedics. Cricothyroidotomy location was correctly identified in 56 of 68 participants with a time to identification range of 2.0 to 38.2 (median 8.6) seconds. Chest NDC (mid-clavicular) location was correctly identified in 54 of 68 participants with a time to identification range of 3.4 to 25.0 (median 9.5) seconds. Chest NDC (anterior axillary) location was correctly identified in 43 of 68 participants with a time to identification range of 1.9 to 37.9 (median 9.6) seconds. Chi-square (2-tail) showed no difference between MTO and field paramedic in cricothyroidotomy site (P = .62), mid-clavicular chest NDC site (P = .21), or anterior axillary chest NDC site (P = .11). There was no difference in time to identification for any procedure between MTO and field paramedic.

Both MTOs and field paramedics were quick in identifying correct placement of cricothyroidotomy and chest NDC location sites. While time to identification was clinically acceptable, there was also a significant proportion that did not identify the correct landmarks.

Needle thoracostomy is the prehospital treatment for tension pneumothorax. Sufficient catheter length is necessary for procedural success. The authors of this study determined minimum catheter length needed for procedural success on a percentile basis.

A meta-analysis of existing studies was conducted. A Medline search was performed using the search terms: needle decompression, needle thoracentesis, chest decompression, pneumothorax decompression, needle thoracostomy, and tension pneumothorax. Studies were included if they published a sample size, mean chest wall thickness, and a standard deviation or confidence interval. A PubMed search was performed in a similar fashion. Sample size, mean chest wall thickness, and standard deviation were found or calculated for each study. Data were combined to create a pooled dataset. Normal distribution of data was assumed. Procedural success was defined as catheter length being equal to or greater than the chest wall thickness.

The Medline and PubMed searches yielded 773 unique studies; all study abstracts were reviewed for possible inclusion. Eighteen papers were identified for full manuscript review. Thirteen studies met all inclusion criteria and were included in the analysis. Pooled sample statistics were: n=2,558; mean=4.19 cm; and SD=1.37 cm. Minimum catheter length needed for success at the 95th percentile for chest wall size was found to be 6.44 cm.

A catheter of at least 6.44 cm in length would be required to ensure that 95% of the patients in this pooled sample would have penetration of the pleural space at the site of needle decompression, and therefore, a successful procedure. These findings represent Level III evidence.

ClemencyBM , TanskiCT , RosenbergM , MayPR , ConsiglioJD , LindstromHA . Sufficient Catheter Length for Pneumothorax Needle Decompression: A Meta-Analysis. Prehosp Disaster Med. 2015;30(3):1 5

Tension pneumothorax is the second leading cause of preventable combat death. Although relatively simple, the management of tension pneumothorax is considered an advanced life support skill set. The purpose of this study was to assess the ability of non-medical law enforcement personnel to learn this skill set and to determine long-term knowledge and skill retention.

After completing a pre-intervention questionnaire, a total of 22 tactical team operators completed a 90-minute-long training session in recognition and management of tension pneumothorax. Post-intervention testing was performed immediately post-training, and at one- and six-months post-training.

Initial training resulted in a significant increase in knowledge (pre: 1.3 ±1.35, max score 7; post: 6.8 ±0.62, p < 0.0001). Knowledge retention persisted at one- and six-months post-training, without significant decrement.

Non-medical law enforcement personnel are capable of learning needle decompression, and retain this knowledge without significant deterioration for at least six months.