Date Published: March 29, 2018
Publisher: BioMed Central
Author(s): Michael M. Neeki, Fanglong Dong, Lidia Liang, Jake Toy, Braeden Carrico, Nina Jabourian, Arnold Sin, Farabi Hussain, Sharon Brown, Keyvan Safdari, Rodney Borger, David Wong.
This study investigates the impact of methamphetamine use on trauma patient outcomes.
This retrospective study analyzed patients between 18 and 55 years old presenting to a single trauma center in San Bernardino County, CA who sustained traumatic injury during the 10-year study period (January 1st, 2005 to December 31st, 2015). Routine serum ethanol levels and urine drug screens (UDS) were completed on all trauma patients. Exclusion criteria included patients with an elevated serum ethanol level (> 0 mg/dL). Those who screened positive on UDS for only methamphetamine and negative for cocaine and cannabis (MA(+)) were compared to those with a triple negative UDS for methamphetamine, cocaine, and cannabis (MA(−)). The primary outcome studied was the impact of a methamphetamine positive drug screen on hospital mortality. Secondary outcomes included length of stay (LOS), heart rate, systolic and diastolic blood pressure (SBP and DBP, respectively), and total amount of blood products utilized during hospitalization. To analyze the effect of methamphetamine, age, gender, injury severity score, and mechanism of injury (blunt vs. penetrating) were matched between MA(−) and MA(+) through a propensity matching algorithm.
After exclusion, 2538 patients were included in the final analysis; 449 were patients in the MA(+) group and 2089 patients in the MA(−) group. A selection of 449 MA(−) patients were matched with the MA(+) group based on age, gender, injury severity score, and mechanism of injury. This led to a final sample size of 898 patients with 449 patients in each group. No statistically significant change was observed in hospital mortality. Notably, a methamphetamine positive drug screen was associated with a longer LOS (median of 4 vs. 3 days in MA(+) and MA(−), respectively, p < 0.0001), an increased heart rate at the scene (103 vs. 94 bpm for MA(+) and MA(−), respectively, p = 0.0016), and an increased heart rate upon arrival to the trauma center (100 vs. 94 bpm for MA(+) and MA(−), respectively, p < 0.0001). Moreover, the MA(+) group had decreased SBP at the scene compared to the MA(−) group (127 vs. 132 bpm for MA(+) and MA(−), respectively, p = 0.0149), but SBP was no longer statistically different when patients arrived at the trauma center (p = 0.3823). There was no significant difference in DBP or in blood products used. Methamphetamine positive drug screens in trauma patients were not associated with an increase in hospital mortality; however, a methamphetamine positive drug screen was associated with a longer LOS and an increased heart rate.
Methamphetamine is a potent stimulant that affects the central nervous system. Use of methamphetamine results in immediate effects that often include euphoria, aggression, erratic behavior, increased libido, emotional lability, and psychosis lasting on average for 6 to 12 h [1–4]. In 2015, an increasing trend of methamphetamine use in the United States among individuals 12 years and older was noted with an estimated 5.4% of the population having tried methamphetamine in their lifetime . Geographically, methamphetamine use is most predominant on the West Coast and in the Midwest; however, the prevalence of use is rapidly spreading east across the United States [1, 5, 6]. This increase in methamphetamine use has been reflected in emergency departments (ED) around the country [1, 7–10]. The economic impact has also been significant [9, 11]. In 2005, the economic burden of methamphetamine use in the United States was estimated to be $23.4 billion .
This retrospective chart review was undertaken at Arrowhead Regional Medical Center (ARMC). ARMC is a 456-bed acute care teaching facility and the only American College of Surgeons certified level II trauma center located in San Bernardino County, CA with over 92,000 visits annually. San Bernardino County is the largest county by area in the contiguous United States with a population of over two million.
Among the 6898 patients included in the original database, 3900 patients were excluded due to elevated serum ethanol levels, 349 patients were excluded due to positive cocaine on UDS, and 111 patients were excluded due to positive cannabis on UDS, which led to a cohort of 2538 patients. A total of 449 patients were positive for MA(+) and 2089 patients were MA(−) (see Fig. 1). A selection of 449 patients in the MA(−) group was matched with MA(+) group based on age, gender, ISS, and mechanism of injury. This led to a final sample size of 898 patients with 449 patients in each group.Fig. 1Patient selection flow chart. *MA(−) = a triple negative drug screen for methamphetamine, cocaine, and cannabis, and serum ethanol level < 0 mg/dL matched to the MA(+) group via propensity score matching. MA(−) was selected to match with MA(+) based on age, gender, ISS, and mechanism of injury. **MA(+) = a positive drug screen for methamphetamine, and negative for cocaine or cannabis, and serum ethanol level < 0 mg/d. ***ISS = injury severity score Although it has been widely established that methamphetamine use results in toxic effects on the body and increases the likelihood of sustaining a traumatic injury, the effects of methamphetamine on traumatic injury outcomes in the post-injury period remain unclear. The current study suggests no change in hospital mortality outcomes and a longer hospital LOS in trauma patients with positive methamphetamine drug screens. With respect to the association between a positive methamphetamine drug screen and trauma patient mortality, Yegiyants et al.  demonstrated a conflicting trend toward reduced mortality among trauma patients who had a positive methamphetamine drug screen. However, Hadjizacharia et al.  noted no significant correlation. Taken together, it appears that a positive methamphetamine drug screen does not correlate with trauma patient mortality. With regards to hospital LOS, the findings of the current study are consistent with select prior reports suggesting that minimally injured trauma patients with positive methamphetamine drug screens have a significantly longer hospital LOS [6, 17]. Yet other studies have reported that trauma patients with positive methamphetamine drug screens did not have an increased LOS in the intensive care unit (ICU) or the hospital, but may be more likely to be admitted to the ICU [17, 19]. This study has several limitations. First, patients seen at our center suffering from traumatic injury during the study period underwent routine drug and alcohol screening prior to admission; however, those directly admitted or who require emergent surgery for life-threatening injuries may not have undergone drug screening. Though a small subset of patients with methamphetamine positive drugs screens may not have been included, the impact on our results was likely minimal given our matching algorthim. The current study suggests that trauma patients with positive methamphetamine drug screens do not have a significant difference in hospital mortality outcomes when compared to those with negative methamphetamine drug screens. Despite these findings, routine urine toxicology screening and measurement of serum ethanol level amongst trauma patients may still be warranted as these findings could assist in medical decision making throughout a patient's hospital course and disposition. Future studies are warranted to further assess the factors that contribute to an increased LOS for trauma patients with positive methamphetamine screens and to develop a greater insight into the clinical value of urine drug testing for trauma patients upon admission. Source: http://doi.org/10.1186/s13722-018-0112-6