Highlights from #AASTAnnualMeeting - Limited Transthoracic Echocardiogram in Trauma Bay

Dr. Paula Ferrada presented an interesting study on the use of Limited Trans-thoracic Echocardiography (LTTE) to direct resuscitation.  Another application of ultrasound during initial resuscitation. She used LTTE to evaluate the IVC and the right ventricle for volume and contractility, and response to fluid.  This approach decreases the amount of fluid infused while still achieving good outcomes.

Introduction: Limited transthoracic echocardiogram (LTTE) has been introduced as a technique to direct resuscitation in trauma patients. We hypothesize that LTTE is a useful tool to guide therapy during the initial phase of resuscitation in trauma patients.

Methods: All highest level alert patients with at least one measurement of systolic blood pressure <100 mmHg, a mean arterial pressure < 60 mmHg, and/or a heart rate >120 bpm who arrived to the trauma bay (TB) at a level 1 center were randomized to have either LTTE performed (LTTEp), or not performed (nonLTTE) as part of their initial evaluation from July 1 to December 31 2012. Images were stored and results were reported regarding contractility (good vs. poor), fluid status (empty inferior vena cava: eIVC [hypovolemic] vs. full inferior vena cava: fIVC [not hypovolemic]), and pericardial effusion (present vs. absent). Time from TB to operating room (OR), intravenous fluid (IVF) administration, blood product requirement, ICU admission, and mortality were examined in both groups.

Results: 240 patients were randomized. 25 patients were excluded since they died upon arrival to the TB, leaving 215 patients in the study. 92 patients were in the LTTEp group with 123 patients in the nonLTTE group. LTTE helped guide resuscitation as patients with eIVC received on average significantly more fluid than patients with fIVC (1.8L vs. 1.0L, p<0.0001). The LTTEp and nonLTTE groups were similar in age, (38 vs. 38.8, p=0.75), ISS (19.2 vs. 19.0, p=0.94), RTS (5.5 vs. 6.0, p=0.09), lactate (4.2 vs. 3.6, p=0.14) and mechanism of injury, (Blunt 64% vs. 63%, penetrating 28% vs. 33%, burns 7.6% vs. 4%, p=0.44). Strikingly, LTTEp had significantly less IVF than nonLTTE patients, (1.5L vs. 2.5L, p<0.0001), less time from TB to OR, (35.6 min vs. 79.1 min, p=0.0006), higher rate of ICU admission, (80.4% vs. 67.2%, p=0.04), and although not statistically significant, a lower mortality rate (11% vs. 19.5%, p=0.09). Mortality differences were particularly evident in the traumatic brain injury (TBI) patients, (14.7% in LTTEp vs.39.5% in nonLTTE, p=0.03) as shown in table 1

Table1 TBI Patients

	LTTEp	nonLTTEp	p value
Mean Age	37y	42y	0.32
Mean ISS	21.7	18.8	0.39
Mean IVF	1.04L	2.4L	<0.0001
Blood Transfusion	17.7%	2.6%	0.05
Min to OR	40min	65min	0.15
Mortality	17.7%	39.5%	p0.0336

Conclusion: LTTE is a useful guide for therapy in hypotensive trauma patients during the early phase of resuscitation. In this study, there was an improved outcome in patients where therapy was guided by LTTE findings