The splenic injury outcomes trial: An American Association for the Surgery of Trauma multi-institutional study. Zarzaur BL, Kozar R, Myers JG, Claridge JA, Scalea TM, Neideen TA, Maung AA, Alarcon L, Corcos A, Kerwin A, Coimbra R. J Trauma Acute Care Surg. 2015 Sep;79(3):335-42.
This manuscript describes an interesting prospective, observational, multi-center trial examining the natural history of blunt splenic injury managed non-operatively for the first 24 hours, managed with and without angioembolization. The study accumulated 383 patients, with informed consent, with 87% follow-up at 180 days after injury. Clinical decision-making was not altered by study participation. An important note, albeit obvious, is that this study excludes patients who had urgent splenectomy within 24 hours of admission for failure of non-operative management. The indications for angioembolization were presence of pseudoaneurysm, contrast extravasation outside the splenic parenchyma, or both, on admission CT scan. A small minority of patients had angioembolization simply for concerning appearance of the spleen on admission CT without pseudoaneurysm or extravasation.
The study population median injury severity score was 22. Approximately half of the study population had AAST grade III, IV, or V splenic injuries. The overall mortality was 1% and no deaths were spleen-related. The risk of in-hospital splenectomy was 3% and the risk of outpatient splenectomy for bleeding within 180 days was 0.25%. All non-operative failures proceeding to splenectomy, with or without angioembolization, occurred within 12 days of injury. About 20% of patients received an angiographic intervention, which was generally main splenic artery embolization. There were no differences in 180 day risk of splenectomy between patients who underwent angioembolization and those who did not, nor were there differences between patients who underwent immediate angioembolization (within 24 hours of admission) compared to those who had delayed embolization (beyond 24 hours of admission).
There are two important conclusions from this study. First, delayed bleeding and splenectomy occurs within 12 days of injury, and this period of time should be cause for vigilance of patients and surgeons. Second, the notion of angioembolization as a mechanism for avoiding splenectomy is drawn into question. The best indications for angioembolization remain unclear.
Impact of common crystalloid solutions on resuscitation markers following Class I hemorrhage: A randomized control trial. Ross SW, Christmas AB, Fischer PE, Holway H, Walters AL, Seymour R, Gibbs MA, Heniford BT, Sing RF. J Trauma Acute Care Surg. 2015 Nov;79(5):732-40.
This manuscript describes a randomized, controlled trial of two types of crystalloid resuscitation versus no resuscitation in patients with Class I hemorrhagic shock created during voluntary blood donation. The study accumulated 157 patients in three randomized arms: 2 liter resuscitation of room temperature normal saline (NS), lactated Ringer’s solution (LR) (both over 20 minutes), or no fluid resuscitation (no-IVF) following 500 mL or whole blood donation. Resuscitation biomarkers were measured after blood donation but before resuscitation, and 30 minutes after blood donation (10 minutes after fluid resuscitation was completed).
There were about 52 patients in each study arm. After 500 mL of blood loss, the mean total blood volume lost was 10.8%. There were no demographic or blood loss differences between groups. All patients receiving NS and LR were hyperchloremic post-resuscitation, while the no-IVF group was not. Both NS and LR resuscitation resulted in worsening acidemia, but the effect size was larger with NS, while the no-IVF group demonstrated no change in pH. Post-resuscitation, lactate was highest in the LR group, which was similar to the no-IVF group. With respect to base deficit, NS resuscitation resulted in a 5 fold greater base deficit compared to no-IVF, and a 10 fold greater base deficit than the LR group.
There are two main conclusions from this paper. First, the measured lactate following resuscitation with LR may not be representative of the development of a true anion gap acidosis resulting from hypoperfusion. LR resuscitation has little effect on base deficit and pH. Consequently, these may be more valuable biomarkers during resuscitation. Second, NS resuscitation does not interfere with the utility of lactate measurement, however NS creates serum acidosis and elevates base deficit by virtue of chloride’s acid effect. Clinicians should be aware of these metabolic alterations as they impact interpretation of endpoints of resuscitation.
Development and Validation of the Air Medical Prehospital Triage Score for Helicopter Transport of Trauma Patients. Brown JB, Gestring ML, Guyette FX, Rosengart MR, Stassen NA, Forsythe RM, Billiar TR, Peitzman AB, Sperry JL. Ann Surg. 2016 Aug;264(2):378-85.
In this study the authors continue their series of investigations using the National Trauma Data Bank (NTDB) to validate the use of helicopter transport of trauma patients. The authors propose a scoring system that can be applied by EMS providers in the field to decide on helicopter versus ground transport of trauma patients. The NTDB was queried for the years 2007 to 2012 to identify 2.1 million subjects, 12% of these were transported by helicopter. The data set was divided into development and validation sets and multiple imputation was used to correct for missing data. Patients with low probability of deriving benefit from helicopter transport (<15 minutes travel time) were excluded. Potential criterion for the scoring system were evaluated based on their association with a survival benefit if coexisting with air transport. Weighted odds for each of the criteria were calculated to identify the relative value of each of the selected criteria. For validation patients who met the investigators criterion were identified in the validation data set and it was determined if they derived a benefit from helicopter transport.
The criteria eventually identified as components of the score included: GCS <14 (1 point), respiratory rate <10 or >29 (1 point), unstable chest wall fracture (1 point), suspected hemothorax or pneumothorax (1 point), paralysis (1 point), multisystem trauma – minimum of 3 systems (1 point), 1 physiologic + 1 anatomic ACS COT field triage criteria (2 points). A score of 2 or more was indicative of deriving a benefit from helicopter transport.
This scoring system has the potential to be a useful tool for field EMS providers in areas where helicopter transport is available. Prospective confirmation of the system will be required as there may be limitations. Although simple in calculation there are several components that are somewhat subjective including, unstable chest wall injury, suspected hemothorax or suspected pneumothorax. Also, the most common missing variable and therefore most commonly imputed, respiratory rate, was a criterion.
FAST ultrasound examination as a predictor of outcomes after resuscitative thoracotomy: a prospective evaluation. Inaba K, Chouliaras K, Zakaluzny S, Swadron S, Mailhot T, Seif D, Teixeira P, Sivrikoz E, Ives C, Barmparas G, Koronakis N, Demetriades D. Ann Surg. 2015 Sep;262(3):512-8; discussion 516-8.
This is a prospective observational single center study using cardiac ultrasound evaluation of patients undergoing resuscitative thoracotomy (RT) in the emergency department immediately upon arrival. Resuscitative thoracotomies were performed in all patients who arrived without vital signs after penetrating trauma or who lost vital signs during transport after blunt trauma. Of 223 patients who met these criteria 187 underwent a cardiac ultrasound either immediately prior to, or concomitant with resuscitative thoracotomy. Of the 187 patients there were six survivors and three organ donors. Two of the survivors were discharged home and two with spinal cord injuries had intact brain function and were discharged to rehabilitation. All of the patients that survived or survived to organ donation had cardiac motion on ultrasound and five of six had penetrating injury.
This is a convincing study in that 187 patients were evaluated with cardiac ultrasound and underwent RT over a 43-month period indicating a center with extensive experience with RT. If a good outcome was possible a center with this level of experience would likely be able to achieve it. Despite the likely high level of skill at this center, they were unable to resuscitate a single patient among 126 attempts when no cardiac activity was present. Although one might otherwise have expected a few survivors from this group, these data set the likely survival rate at <<1% when no cardiac activity is present. Additional high quality studies will be necessary, but if the findings of this study are confirmed, RC may no longer be warranted in cases of ultrasound documented absence of cardiac activity when the necessary ultrasound skill is available.