Evaluation of a novel thoracic entry device versus needle decompression in a tension pneumothorax swine model

Prehospital Trauma Compendium: Traumatic Pneumothorax Care - a position statement and resource document of NAEMSP

Emergency Medical Services (EMS) clinicians manage patients with traumatic pneumothoraces. These may be simple pneumothoraces that are less clinically impactful, or tension pneumothoraces that disturb perfusion, lead to shock, and impart significant risk for morbidity and mortality. Needle thoracostomy is the most common EMS treatment of tension pneumothorax, but despite the potentially life-saving value of needle thoracostomy, reports indicate frequent misapplication of the procedure as well as low rates of successful decompression. This has led some to question the value of prehospital needle thoracostomy and has prompted consideration of alternative approaches to management (e.g., simple thoracostomy, tube thoracostomy). EMS clinicians must determine when pleural decompression is indicated and optimize the safety and effectiveness of the procedure. Further, there is also ambiguity regarding EMS management of open pneumothoraces. To provide evidence-based guidance on the management of traumatic pneumothoraces in the EMS setting, NAEMSP performed a structured literature review and developed the following recommendations supported by the evidence summarized in the accompanying resource document.NAEMSP recommends:EMS identification of a tension pneumothorax must be guided by a combination of risk factors and physical findings, which may be augmented by diagnostic technologies.EMS clinicians should recognize the differences in the clinical presentation of a tension pneumothorax in spontaneously breathing patients and in patients receiving positive pressure ventilation.EMS clinicians should not perform pleural decompression in patients with simple pneumothoraces but should perform pleural decompression in patients with tension pneumothorax, if within the clinician's scope of practice.When within scope of practice, EMS clinicians should use needle thoracostomy as the primary strategy for pleural decompression of tension pneumothorax in most cases. EMS clinicians should take a patient-individualized approach to performing needle thoracostomy, influenced by factors known to impact chest wall thickness and risk for iatrogenic injury.Simple thoracostomy and tube thoracostomy may be used by highly trained EMS clinicians in select clinical settings with appropriate medical oversight and quality assurance.EMS systems must investigate and adopt strategies to confirm successful pleural decompression at the time thoracostomy is performed.Pleural decompression should be performed for patients with traumatic out-of-hospital circulatory arrest (TOHCA) if there are clinical signs of tension pneumothorax or suspicion thereof due to significant thoraco-abdominal trauma. Empiric bilateral decompression, however, is not routinely indicated in the absence of such findings.EMS clinicians should not routinely perform pleural decompression of suspected or confirmed simple pneumothorax prior to air-medical transport in most situations.EMS clinicians may consider placement of a vented chest seal in spontaneously breathing patients with open pneumothoraces.In patients receiving positive pressure ventilation who have open pneumothoraces, chest seals may be harmful and are not recommended.EMS physicians play an important role in developing curricula and leading quality management programs to both ensure that EMS clinicians are properly trained in the recognition and management of tension pneumothorax and to ensure that interventions for tension pneumothorax are performed appropriately, safely, and effectively.

Mid‐Arm Point in PAEDiatrics (MAPPAED): An effective procedural aid for safe pleural decompression in trauma

OBJECTIVE

Life-threatening thoracic trauma requires emergency pleural decompression and thoracostomy and chest drain insertion are core trauma procedures. Reliably determining a safe site for pleural decompression in children can be challenging. We assessed whether the Mid-Arm Point (MAP) technique, a procedural aid proposed for use with injured adults, would also identify a safe site for pleural decompression in children.

METHODS

Children (0-18 years) attending four EDs were prospectively recruited. The MAP technique was performed, and chest wall skin marked bilaterally at the level of the MAP; no pleural decompression was performed. Radio-opaque markers were placed over the MAP-determined skin marks and corresponding intercostal space (ICS) reported using chest X-ray.

RESULTS

A total of 392 children participated, and 712 markers sited using the MAP technique were analysed. Eighty-three percentage of markers were sited within the 'safe zone' for pleural decompression (4th to 6th ICSs). When sited outside the 'safe zone', MAP-determined markers were typically too caudal. However, if the site for pleural decompression was transposed one ICS cranially in children ≥4 years, the MAP technique performance improved significantly with 91% within the 'safe zone'.

CONCLUSIONS

The MAP technique reliably determines a safe site for pleural decompression in children, albeit with an age-based adjustment, the Mid-Arm Point in PAEDiatrics (MAPPAED) rule: 'in children aged ≥4 years, use the MAP and go up one ICS to hit the safe zone. In children <4 years, use the MAP.' When together with this rule, the MAP technique will identify a site within the 'safe zone' in 9 out of 10 children.

Comparison of 10- versus 14-gauge angiocatheter for treatment of tension pneumothorax and tension-induced pulseless electrical activity with hemorrhagic shock: Bigger is still better

BACKGROUND

Little is known regarding the effect of hemorrhagic shock on the diagnosis and treatment of tension pneumothorax (tPTX). Recently, the Tactical Combat Casualty Care guidelines included the 10-gauge angiocatheter (10-g AC) as an acceptable alternative to the 14-g AC. This study sought to compare these two devices for decompression of tPTX and rescue from tension-induced pulseless electric activity (tPEA) in the setting of a concomitant 30% estimated blood volume hemorrhage.

METHODS

Following a controlled hemorrhage, carbon dioxide was insufflated into the chest to induce either tPTX or tPEA. Tension pneumothorax was defined as a reduction in cardiac output by 50%, and tPEA was defined as a loss of arterial waveform with mean arterial pressure less than 20 mm Hg. The affected hemithorax was decompressed using a randomized 14-g AC or 10-g AC while a persistent air leak was maintained after decompression. Successful rescue from tPTX was defined as 80% recovery of baseline systolic blood pressure, while successful return of spontaneous circulation following tPEA was defined as a mean arterial pressure greater than 20 mm Hg. Primary outcome was success of device.

RESULTS

Eighty tPTX and 50 tPEA events were conducted in 38 adult Yorkshire swine. There were no significant differences in the baseline characteristics between animals or devices. In the tPTX model, the 10-g AC successfully rescued 90% of events, while 14-g AC rescued 80% of events (p = 0.350). In the tPEA model, the 10-g AC rescued 87% of events while the 14 AC rescued only 48% of events (p = 0.006).

CONCLUSION

The 10-g AC was vastly superior to the 14-g AC for return of spontaneous circulation following tPEA in the setting of 30% hemorrhage. These findings further support the importance of larger caliber devices that facilitate rapid recovery from tPTX, particularly in the setting of polytrauma.

LEVEL OF EVIDENCE

Therapeutic, level II.

An Evaluation of a Novel Medical Device Versus Standard Interventions in the Treatment of Tension Pneumothorax in a Swine Model (Sus scrofa)

INTRODUCTION

Tension pneumothorax is a common cause of preventable death in trauma. Needle decompression is the traditional first-line intervention but has high failure rates. We sought to evaluate the effectiveness and expedience of needle thoracostomy, surgical tube thoracostomy, and Reactor™ thoracostomy - a novel spring-loaded trocar insertion device.

MATERIALS AND METHODS

Yorkshire swine underwent controlled thoracic insufflation to create tension pneumothorax physiology for device comparison. Additional experiments were performed by increasing insufflation pressures to achieve pulseless electrical activity. Intervention was randomized to needle thoracostomy (14 gauge), tube thoracostomy (32Fr), or Reactor™ thoracostomy (36Fr). Air leak was simulated throughout intervention with 40-80 mL/kg/min insufflation. Intrathoracic pressure monitoring and hemodynamic parameters were obtained at 1 and 5 minutes.

RESULTS

Tension physiology and tension-induced pulseless electrical activity were created in all iterations. Needle thoracostomy (n = 28) was faster at 7.04 ± 3.04 seconds than both Reactor thoracostomy (n = 32), 11.63 ± 5.30 (p < 0.05) and tube thoracostomy (n = 32), 27.06 ± 10.73 (p < 0.01); however, Reactor™ thoracostomy was faster than tube thoracostomy (p < 0.001). Physiological decompression was achieved in all patients treated with Reactor™ and tube thoracostomy, but only 14% of needle thoracostomy. Cardiac recovery to complete physiologic baseline occurred in only 21% (6/28) of those treated with needle thoracostomy whereas Reactor™ or tube thoracostomy demonstrated 88% (28/32) and 94% (30/32) response rates. When combined, needle thoracostomy successfully treated tension pneumothorax in only 4% (1/28) of subjects as compared to 88% (28/32) with Reactor™ thoracostomy and 94% (30/32) with tube thoracostomy (p < 0.01).

CONCLUSIONS

Needle thoracostomy provides a rapid intervention for tension pneumothorax, but is associated with unacceptably high failure rates. Reactor™ thoracostomy was effective, expedient, and may provide a useful and technically simpler first-line treatment for tension pneumothorax or tension-induced pulseless electrical activity.

Thoracostomy in children with severe trauma: An overview of the paediatric experience in Victoria, Australia

OBJECTIVE

Thoracic trauma is a leading cause of paediatric trauma deaths. Traumatic cardiac arrest, tension pneumothorax and massive haemothorax are life-threatening conditions requiring emergency and definitive pleural decompression. In adults, thoracostomy is increasingly preferred over needle thoracocentesis for emergency pleural decompression. The present study reports on the early experience of thoracostomy in children, to inform debate regarding the best approach for emergency pleural compression in paediatric trauma.

METHODS

Retrospective review of Ambulance Victoria and The Royal Children's Hospital Melbourne, Trauma Registry between August 2016 and February 2019 to identify children undergoing thoracostomy for trauma, either pre-hospital or in the ED.

RESULTS

Fourteen children aged 1.2-15 years underwent 23 thoracostomy procedures over the 31 month period. The majority of patients sustained transport-related injuries, and underwent thoracostomies for the primary indications of hypoxia and hypotension. Two children were in traumatic cardiac arrest. Ten children underwent needle thoracocentesis prior to thoracostomy, but all required thoracostomy to achieve the necessary definitive decompression. All patients were severely injured with multiple-associated serious injuries and median Injury Severity Score 35.5 (17-75), three of whom died from their injuries. Thoracostomy in our cohort had a low complication rate.

CONCLUSION

In severely injured children, thoracostomy is an effective and reliable method to achieve emergency pleural decompression, including in the young child. The technical challenges presented by children are real, but can be addressed by training to support a low complication rate. We recommend thoracostomy over needle thoracocentesis as the first-line intervention in children with traumatic cardiac arrest, tension pneumothorax and massive haemothorax. [Correction added on 23 September 2019 after first online publication: in the second sentence of the conclusion, the words "under review process" were mistakenly added and have been removed.].

Comparison of a novel, endoscopic chest tube insertion technique versus the standard, open technique performed by novice users in a human cadaver model: a randomized, crossover, assessor-blinded study

Background

The technique of tube thoracostomy has been standardized for years without significant updates. Alternative procedural methods may be beneficial in certain prehospital and inpatient environments with limited resources. We sought to compare the efficacy of chest tube insertion using a novel, endoscopic device (The Reactor™) to standard, open tube thoracostomy.

Methods

Novice users were randomly assigned to pre-specified sequences of six chest tube insertions performed on a human cadaver model in a crossover design, alternating between the Reactor™ and standard technique. All subjects received standardized training in both procedures prior to randomization. Insertion site, which was randomly assigned within each cadaver’s hemithorax, was marked by the investigators; study techniques began with skin incision and ended with tube insertion. Adequacy of tube placement (intrapleural, unkinked, not in fissure) and incision length were recorded by investigators blinded to procedural technique. Insertion time and user-rated difficulty were documented in an unblinded fashion. After completing the study, participants rated various aspects of use of the Reactor™ compared to the standard technique in a survey evaluation.

Results

Sixteen subjects were enrolled (7 medical students, 9 paramedics) and performed 92 chest tube insertions (n = 46 Reactor™, n = 46 standard). The Reactor™ was associated with less frequent appropriate tube positioning (41.3% vs. 73.9%, P = 0.0029), a faster median insertion time (47.3 s, interquartile range 38–63.1 vs. 76.9 s, interquartile range 55.3–106.9, P < 0.0001) and shorter median incision length (28 mm, interquartile range 23–30 vs. 32 mm, interquartile range 26–40, P = 0.0034) compared to the standard technique. Using a 10-point Likert scale (1-easiest, 10-hardest) participants rated the ease of use of the Reactor™ no different from the standard method (3.8 ± 1.9 vs. 4.7 ± 1.9, P = 0.024). The Reactor™ received generally favorable scores for all parameters on the post-participation survey.

Conclusions

In this randomized, assessor-blinded, crossover human cadaver study, chest tube insertion using the Reactor™ device resulted in faster insertion time and shorter incision length, but less frequent appropriate tube placement compared with the standard technique. Additional studies are needed to evaluate the efficacy, safety and potential advantages of this novel device.

Failure Rate of Prehospital Needle Decompression for Tension Pneumothorax in Trauma Patients

Tension pneumothorax is commonly treated with needle decompression (ND) at the 2nd intercostal space midclavicular line (2nd ICS MCL) but is thought to have a high failure rate. Few studies have attempted to directly measure the failure rate in patients receiving the intervention. We performed a retrospective analysis of 10 years of patients receiving prehospital ND. CT scans were reviewed to record the location of catheters left indwelling and the proportion of patients who did not have any pneumothorax. Chest wall thickness was measured on both injured and uninjured sides at the 2nd ICS MCL and compared with the recommended alternative, the 5th ICS anterior axillary line (5th ICS AAL). We identified 335 patients that underwent prehospital ND who had CT scans performed. Using our two different radiologic methods of assessing failure, 39 per cent and 76 per cent of attempts at ND failed to reach the pleural space. In addition, at least 39 per cent of patients did not have a tension pneumothorax. Injured chest walls were significantly thicker than uninjured chest walls at both the 2nd ICS MCL and the 5th ICS AAL (both P < 0.005.) Increasing chest wall thickness correlated with the failure of the catheter to reach the pleural space. Using an 8-cm catheter at the 5th ICS AAL, iatrogenic cardiac injury was at risk in 42 per cent of patients. This series confirms the high failure rate of ND at the 2nd ICS MCL, but further studies are needed to assure the safety of using larger catheters at the 5th ICS AAL.