Abstract
Objective
We compared the outcomes of patients with tube thoracostomy for chest trauma between the prehospital and inhospital settings.
Methods
The subjects were then divided into 2 groups: the prehospital group, which included subjects who underwent tube thoracostomy in the prehospital setting, and the inhospital group, which included subjects who underwent tube thoracostomy in the inhospital setting. The variables were compared between the 2 groups.
Results
There were no significant differences between the 2 groups with regard to gender, age, history, mechanism of injury, infusion of antibiotics, white blood cell count, duration of insertion of a chest drain, mechanical ventilation, complication of drain infection, duration of admission, or final outcome. However, the Injury Severity Score, maximum C-reactive protein level, and maximum temperature during hospitalization in the prehospital group (n = 15) were significantly greater than those in the inhospital group (n = 119).
Conclusion
The present study suggested that thoracostomy performed by physicians in the prehospital setting was safe and did not have an increased risk of infection. In addition, thoracostomy for chest injury in the prehospital setting suggested an improvement in the likelihood of a survival outcome.
Thoracostomy has evolved as a primary treatment for the evacuation of air or fluid in the pleural space due to a myriad of causes.
1
Air within the pleural space is 1 of the most common reasons for chest tube insertion. In the context of a pneumothorax, indications include a large primary or secondary pneumothorax, mechanically ventilated patients with a pneumothorax or effusions to decrease, a pneumothorax with a hemodynamically unstable patient, a recurrent or persistent pneumothorax, a tension pneumothorax, and a pneumothorax related to trauma.1
Prehospital intervention, including tube thoracostomy performed by skilled emergency medical service providers during ground or air transport, has an advantageous effect on the outcomes of severely injured trauma patients.2
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However, the use of prehospital chest tube thoracostomy remains controversial because of the presumed increase in complication risk. 3In 2004, our hospital in eastern Shizuoka Prefecture, which is a popular sightseeing and leisure spot for people who live in metropolitan areas, such as Tokyo, began to provide a physician-staffed helicopter emergency medical service (HEMS) and directly transported patients with various disease and injuries from the scene to a medical facility or performed interhospital air transportation.
4
In Japan, the HEMS is used during the daytime, and a request for dispatch can only be executed by the fire department or physicians in medical facilities. The HEMS crew generally consists of 1 pilot, 1 mechanic, 1 doctor, and 1 nurse and can increase to up to 3 doctors and 2 nurses for mass casualty cases. Our hospital (Juntendo University Shizuoka Hospital), which is located approximately 130 km southwest of Tokyo, serves as the base hospital for the HEMS in eastern Shizuoka Prefecture and performed the second greatest number of HEMS dispatches in Japan in 2019.4
We receive about 6,000 emergency patients by ambulance or HEMS per year among a population of about 1,200,000 people.Among these patients, some with thoracic trauma underwent tube thoracostomy in the prehospital setting by physicians on board the HEMS or in a physician-staffed ambulance (doctor car system).
5
Few reports concerning the outcomes of patients who undergo indwelling tube thoracostomy by physicians in the prehospital setting have been published. Therefore, we retrospectively investigated and compared the outcomes of patients with tube thoracostomy for chest trauma between the prehospital and inhospital settings.Methods
This study was approved by the Ethics Committee of Juntendo Shizuoka Hospital. The approval number was 298.
We investigated and compared the outcomes of patients with tube thoracostomy for chest trauma between the prehospital and inhospital settings. The primary outcome was to investigate the ratio of infectious complication, and the secondary outcome was to investigate the ratio of a survival outcome.
We performed a retrospective medical chart review of all trauma patients who underwent tube thoracostomy in the prehospital or inhospital setting from April 2016 to March 2020. The indications for tube thoracostomy in the prehospital setting in our HEMS were signs of unstable circulation (eg, hypotension, tachycardia, and/or cold sweat in addition to hypoxia requiring oxygen for patients with chest trauma). Tube thoracostomy in the prehospital setting was performed in the ground ambulance, which transported the traumatized patient and maintained a consistent room temperature using an air conditioner, either at the rendezvous zone or while driving the ground ambulance to a nearby receiving hospital. In the former case, the patient was transported by the HEMS. In the latter case, we called the doctor car system. Patients with cardiac arrest when physicians encountered them, those with endogenous disease (a spontaneous pneumothorax or empyema), and those who were not able to be followed up because of transportation to another hospital were excluded from the analysis.
We collected the following data for each subject: sex, age, history, Injury Severity Score (ISS), mechanism of injury, infusion of antibiotics, maximum parameter values (C-reactive protein, white blood cell, and body temperature) during hospitalization, duration of insertion of a chest drain, mechanical ventilation status, complication of drain infection, duration of admission, and final outcome (survival or death). The subjects were then divided into 2 groups: the prehospital group, which included subjects who underwent tube thoracostomy in the prehospital setting, and the inhospital group, which included subjects who underwent tube thoracostomy in the inhospital setting. The variables mentioned previously were compared between the 2 groups.
The JMP 15.0 software program (SAS Japan Incorporation, Tokyo, Japan) was used to perform the statistical analyses. A nonpaired Student t-test or chi-square test was used for the statistical analyses. P values <.05 were considered to indicate a statistically significant difference. Data are reported as the mean and standard deviation.
Results
During the investigation period, HEMS was dispatched 5,240 times. Among them, 2,612 dispatches were for endogenous diseases, and 2,628 dispatches (including 2,177 for trauma) were for exogenous disease. During the same period, a total of 158 patients underwent tube thoracostomy by the physicians of our department. Among these patients, there were 22 with cardiac arrest, 1 with a spontaneous pneumothorax, and 1 with empyema. After excluding these patients, a total of 134 patients were enrolled as subjects. There were 15 patients in the prehospital group and 119 in the inhospital group. All the 15 patients in the prehospital group and 45 patients in the inhospital group were managed by HEMS. The remaining 74 patients in the inhospital group were transported by ground ambulance by the fire department. All 45 patients managed by HEMS in the inhospital setting had stable circulation; however, tube thoracostomy was performed based on the results of a radiologic study.
The results of an analysis between the 2 groups are shown in Table 1. There were no significant differences between the 2 groups with regard to sex, age, history, mechanism of injury, infusion of antibiotics, white blood cell count, duration of insertion of a chest drain, mechanical ventilation, complication of drain infection, duration of admission, or final outcome. However, the ISS, maximum C-reactive protein level, and maximum temperature during hospitalization in the prehospital group were significantly greater than those in the inhospital group.
Table 1Results of the Analysis
| Prehospital Group | Inhospital Group | P Value | |
|---|---|---|---|
| n = 15 | n = 119 | ||
| Age | 56.3 ± 19.58 | 58.7 ± 19.11 | .65 |
| Sex male/female | 12/3 | 89/29 | .69 |
| Mechanism of injury | .34 | ||
| Fall | 5 | 58 | |
| Penetrating | 1 | 2 | |
| Traffic accident | 9 | 49 | |
| Other | 0 | 10 | |
| Injury Severity Score | 19.2 ± 6.7 | 15.6 ± 8.4 | .025 |
| Mechanical ventilation (yes/no) | 8/7 | 57/62 | .15 |
| Maximum level of WBC | 19,836 ± 9.95 | 15,979 ± 6,994 | .18 |
| Maximum C-reactive protein | 21.6 ± 9.2 | 12.8 ± 9.1 | .053 |
| Maximum body temperature | 39.0 ± 1.1 | 38.2 ± 0.8 | .024 |
| Antibiotics | 8 | 57 | .69 |
| Duration of insertion of a chest drain | 6.40 ± 2.11 (n = 10) | 7.06 ± 2.71 (n = 118) .36 | .36 |
| Complication of drain infection | 0 | 8 | .30 |
| Duration of admission (d) | 27.2 ± 5.73 (n = 10) | 23.1 ± 1.89 (n = 117) .56 | .56 |
| Survival | 15 | 109 | .24 |
WBC = white blood cell.
Discussion
The present study showed that tube thoracostomy inserted by physicians resulted in a 0% occurrence of infection. In addition, the patients in the prehospital group tended to have a more severe condition than those in the inhospital group; however, the survival ratio was not significantly different between the 2 groups. Thus, thoracostomy for chest injury in the prehospital setting was suggested to be associated with an improved survival outcome.
Concerning thoracostomy with infection, we performed a PubMed search to identify any related articles using the keywords “prehospital,” “thoracostomy,” and “infection.” The reports that described the patients who underwent tube thoracostomy in the prehospital setting are summarized in Table 2.
3
,6
, 7
, 8
, 9
, 10
, 11
, 12
, 13
The infection rate in previous reports ranged from 0% to 9%, and our results showed the minimum value (0%). Among previous studies, only 2 involved investigations with control subjects, and both found no significant difference in the infection rate from the controls, which is similar to our own findings. When we perform thoracostomy in the prehospital setting, we disinfect the chest with iodine and use a square sterilization cloth, gloves, and tubes in the same manner as when performing this procedure in the hospital. In addition, after patients arrive at the hospital, the thoracostomy region is disinfected with iodine again. These efforts might have contributed to the lack of infection in cases of tube thoracostomy in the present study.Table 2Previous Reports of Patients Who Underwent Tube Thoracostomy in the Prehospital Setting
| Reporter | Year | Number | Comments | Staff | Infection (%) | Survive (%) | Control |
|---|---|---|---|---|---|---|---|
| Mohrsen | 2021 | 352 | Prehospital thoracostomies are associated with a 10.6% complication rate. | ? | 2 (0.5) | ? | None |
| Kaserer | 2017 | 6 | NT is associated with a high failure rate of more than 80%. | Paramedic | 0 | ? | None |
| Peters | 2017 | 144 | 2/144 traumatic cardiac arrest survivors | Physician | 0 | 2 (1.3) | None |
| High | 2016 | 250 | 30% of patients exhibited clinical improvement. | Nurse | 11 (4) | 75 (30) | None |
| Aylwin | 2008 | 52 | A total of 31% of chest tubes were poorly positioned. | Physician | 1 (1.9) | ? | None |
| Massarutti | 2006 | 55 | Prehospital treatment of a traumatic pneumothorax by simple thoracostomy without chest tube insertion is safe. | Physician | 0 | 40 (72) | None |
| Spanjersberg | 2005 | 22 | The infection rate for prehospital TT does not differ from ED TT. | Physician | 2 (9) | ? | ED |
| Schmidt | 1998 | 63 | Prehospital chest tube thoracostomy is safe and effective. | Physician | 0 | 48 (76) | None |
| York | 1993 | 72 | AMC is often used to treat patients with high acuity, as reflected by the ISS and trauma scores and overall high mortality. The rate of infection between CTT performed by AMC and TS was similar. | Nonphysician | 2 (2.7) | 43 (59) | ED |
| Present | 15 | Physician | 0 | 15 (100) | ED |
AMC = air medical crew; CTT = chest tube thoracostomy; ED = emergency department; ISS = Injury Severity Score; NT = needle thoracocentesis; TS = trauma service; TT = tube thoracostomy.
Concerning the survival ratio, the prehospital group showed a worse ratio than the inhospital group in the present study, although the survival ratio was not significantly different between the 2 groups. A greater ISS usually results in a lower survival ratio even in cases of thoracic injury.
14
,15
Accordingly, tube thoracostomy in the prehospital setting might have been associated with the improvement in the survival rate in the present study. To our knowledge, this is the first report to suggest the usefulness of tube thoracostomy in the prehospital setting for improving the survival ratio of patients with severe thoracic injury, which is in contrast to the findings of York et al.12
The studies of York et al and our group differed with regard to the severity of injury and the treating staff. York et al treated more severely injured patients (average ISS of 39 vs. 19 in the present study), including those with cardiac arrest, who were thought to be unable to be rescued. In addition, trained nurses and paramedics performed tube thoracostomy in the study of York et al after positive results were obtained when performing needle decompression. Needle decompression tends to have a high failure rate when trying to determine the indications for performing tube thoracostomy.16
Furthermore, York et al described 3 tube thoracostomies that ended in failure even though the tubes had been inserted correctly. The direct indwelling of a chest tube by trained physicians without failure in the present study might have resulted in the differing results between these 2 studies. Lastly, differences in training, ongoing education, indications for the procedure, and the n value of the procedures performed over time between the 2 studies may all be confounding factors that influenced the differing results of these 2 studies. However, unfortunately, we could not compare such factors between the 2 studies quantitatively because we did not have exact data. To become a flight physician in our institute, a physician should undergo at least 1 year of training in an emergency room to learn lifesaving techniques and should then undergo more than 6 months of on-the-job training supervised by an expert flight physician until passing the clinical examinations.A previous report suggested that needle thoracostomy, not tube thoracostomy, might be safely performed by paramedics in an emergency medical system that includes urban, rural, and wilderness settings.
17
However, prehospital successful release of a tension pneumothorax was reported by paramedics in 83% (5/6) of cases of tube thoracostomy, whereas needle thoracostomy was effective in only 18% (3/17).8
Accordingly, our policy dictates routinely performing indwelling tube thoracotomy in the prehospital setting.The main limitation of the present study is its basis on retrospective data and a small population from a single medical institute. Thus, a prospective survey and study through joint research at other facilities in the future should be conducted.
Conclusion
The present study suggested that thoracostomy performed by physicians in the prehospital setting was safe and did not have an increased risk of infection. The placement of a chest tube by trained physicians and repeated sterilization of the insertion site on the first day may be the reason. In addition, thoracostomy for chest injury in the prehospital setting suggested an improvement in the likelihood of a survival outcome.
References
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- Decreased mortality after prehospital interventions in severely injured trauma patients.J Trauma Acute Care Surg. 2015; 79: 227-231
- Prehospital chest tube thoracostomy: effective treatment or additional trauma?.J Trauma. 2005; 59: 96-101
- Analysis of the dispatch of physician staffed-helicopters in the COVID-19 pandemic.Am J Emerg Med. 2022; 54: 306-308
- Management of mass casualties using doctor helicopters and doctor cars.Air Med J. 2017; 36: 203-207
- Complications associated with pre-hospital open thoracostomies: a rapid review.Scand J Trauma Resusc Emerg Med. 2021; 29: 166
- Safety and efficacy of thoracostomy in the air medical environment.Air Med J. 2016; 35: 227-230
- Failure rate of prehospital chest decompression after severe thoracic trauma.Am J Emerg Med. 2017; 35: 469-474
- Prehospital thoracostomy in patients with traumatic circulatory arrest: results from a physician-staffed helicopter emergency medical service.Eur J Emerg Med. 2017; 24: 96-100
- Simple thoracostomy in prehospital trauma management is safe and effective: a 2-year experience by helicopter emergency medical crews.Eur J Emerg Med. 2006; 13: 276-280
- Chest tube decompression of blunt chest injuries by physicians in the field: effectiveness and complications.J Trauma. 1998; 44: 98-101
- A comparison study of chest tube thoracostomy: air medical crew and in-hospital trauma service.Air Med J. 1993; 12: 227-229
- Pre-hospital and in-hospital thoracostomy: indications and complications.Ann R Coll Surg Engl. 2008; 90: 54-57
- A comparison of physician-staffed helicopters and ground ambulances transport for the outcome of severe thoracic trauma patients.Am J Emerg Med. 2021; 45: 358-360
- Prognostic factors in trauma patients transported by physician-staffed helicopter in Japan: an investigation based on the Japan Trauma Data Bank.Air Med J. 2020; 39: 494-497
- Failure rate of prehospital needle decompression for tension pneumothorax in trauma patients.Am Surg. 2018; 84: 1750-1755
- Needle thoracotomy in the prehospital setting: a retrospective observational study.Prehosp Emerg Care. 2016; 20: 399-403
Article info
Publication history
Published online: November 17, 2022
Footnotes
Supported in part by a Grant-in-Aid for Special Research in Subsidies for ordinary expenses of private schools from The Promotion and Mutual Aid Corporation for Private Schools of Japan.
Identification
Copyright
© 2022 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.
