The Impact of Flame Burn Injuries on Patients Who Sustain Mild Injuries From Motor Vehicle Crashes.

BACKGROUND: The purpose of this study was to determine the differences in patient outcomes between motor vehicle crash (MVC) victims with an ISS < 15 and those with a similar ISS and a flame burn injury. METHODS: Data for patients involved in a MVC with a GCS ≥12 and an ISS < 15 with and without flame burn injury were reviewed from the American College of Surgeons National Trauma Data Bank between 2007 and 2017. International Classification of Diseases-9 and -10 revisions and External Injury Codes were used to identify patients who were divided into MVC only (Group 1) and MVC with additional flame burn injury (Group 2). In-hospital mortality was the primary outcome whereas secondary outcomes included ICU admission, ICU length of stay (LOS), hospital LOS, sepsis, deep vein thrombosis, acute respiratory distress syndrome, and pneumonia. Simple linear regression was used in the form of odds ratios to investigate risk factors for mortality and secondary outcomes. RESULTS: The mean LOS and ICU LOS were longer in Group 2 (5.9 vs 4.0 days, p-value <0.001, and 1.2 vs 0.6 days, p-value <0.001, respectively), with more patients being admitted to the ICU as well (22.9% vs 17.3%, p-value <0.001). Also, there were significantly higher rates of pneumonia (0.8% vs 0.5%, p-value 0.0014), deep vein thrombosis (0.6% vs 0.4%, p-value 0.028), and acute respiratory distress syndrome (0.5% vs 0.3%, p-value 0.004) in Group 2. Patients in Group 1 were older and more likely had hypertension, congestive heart failure, and COPD. There was no significant difference in mortality between Groups by odds ratios (OR 0.85, p-value 0.743) or raw percentages (0.3% vs 0.3%, p-value = 0.874). CONCLUSION: MVC victims with mild injuries who also sustain a burn injury are more likely to require admission to the ICU regardless of their comorbidities and more likely to develop respiratory complications, especially pneumonia and an increase in ICU and hospital LOS.

Admission Lymphopenia is Associated With Discharge Disposition in Blunt Chest Wall Trauma Patients.

BACKGROUND: Lymphopenia contributes to the immune suppression observed in critical illness. However, its role in the immunologic response to trauma remains unclear. Herein, we assessed whether admission lymphopenia is associated with poor outcomes in patients with blunt chest wall trauma (BCWT). METHODS: All adult patients with a Chest Abbreviated Injury Score (CAIS) ≥2 admitted to our Level I Trauma center between May 2009 and December 2018 were identified in our institution Trauma Registry. Patients with absolute lymphocyte counts (ALC) collected within 24 H of admission were included. Patients who died within 24 H of admission, had bowel perforation on admission, penetrating trauma, and burns were excluded. Demographics, injury characteristics, comorbidities, ALC, complications, and outcomes were collected. Lymphopenia was defined as an ALC ≤1000/µL. Association between lymphopenia and clinical outcomes of BCWT was assessed using multivariate analyses. P < 0.05 was considered significant. RESULTS: A total of 1394 patients were included; 69.7% were male; 44.3% were lymphopenic. On univariate analysis, lymphopenia was associated with longer in-hospital stay (11.6±10.2 versus 10.1±11.4, P = 0.009), in-hospital death (9.7% versus 5.8%, P = 0.006), and discharge to a healthcare facility (60.9% versus 46.4%, P < 0.001). Controlling for Injury Severity Score, age, gender, and comorbidities, the association between lymphopenia and discharge to another facility (SNF/rehabilitation facility/ACH) (OR = 1.380 [1.041-1.830], P = 0.025) remained significant. CONCLUSIONS: Lymphopenia on admission is associated with discharge requiring increased healthcare support. Routine lymphocyte count monitoring on admission may provide important prognostic information for BCWT patients.

Admission Lymphopenia Predicts Infectious Complications and Mortality in Traumatic Brain Injury Victims.

BACKGROUND: Traumatic brain injury (TBI) is a major cause of mortality and disability associated with increased risk of secondary infections. Identifying a readily available biomarker may help direct TBI patient care. Herein, we evaluated whether admission lymphopenia could predict outcomes of TBI patients. METHODS: This is a 10-year retrospective review of TBI patients with a head Abbreviated Injury Score 2 to 6 and absolute lymphocyte counts (ALC) collected within 24 h of admission. Exclusion criteria were death within 24 h of admission and presence of bowel perforation on admission. Demographics, admission data, injury severity score, mechanism of injury, and outcomes were collected. Association between baseline variables and outcomes was analyzed. RESULTS: We included 2,570 patients; 946 (36.8%) presented an ALC ≤1,000 on admission (lymphopenic group). Lymphopenic patients were significantly older, less likely to smoke, and more likely to have heart failure, hypertension, or chronic kidney disease. Lymphopenia was associated with increased risks of mortality (OR = 1.903 [1.389-2.608]; P < 0.001) and pneumonia (OR = 1.510 [1.081-2.111]; P = 0.016), increased LOS (OR = 1.337 [1.217-1.469]; P < 0.001), and likelihood of requiring additional healthcare resources at discharge (OR = 1.669 [1.344-2.073], P < 0.001). Additionally, lymphopenia increased the risk of early in-hospital death (OR = 1.459 [1.097-1.941]; P = 0.009). Subgroup analysis showed that lymphopenia was associated with mortality in polytrauma patients and those who presented with two or more concurrent types of TBI. In all subgroup analyses, lymphopenia was associated with longer length of stay and discharge requiring higher level of care. CONCLUSION: A routine complete blood count with differential for all TBI patients may help predict patient outcomes and direct care accordingly.

Patient and healthcare provider perspectives on adherence with antihypertensive medications: an exploratory qualitative study in Tanzania.

BACKGROUND: Poor medication adherence is an extraordinarily common problem worldwide that contributes to inadequate control of many chronic diseases, including Hypertension (HT). Globally, less than 14% of the estimated 1.4 billion patients with HT achieve optimal control. A myriad of barriers, across patient, healthcare provider, and system levels, contributes to poor medication adherence. Few studies have explored the reasons for poor medication adherence in Tanzania and other African countries. METHODS: A qualitative study applying grounded theory principles was conducted in the catchment area of two semi-urban clinics in Dar es Salaam, Tanzania, to determine the perceived barriers to HT medication adherence. Ten key informant interviews were conducted with healthcare providers who manage HT patients. Patients diagnosed with HT (SBP ≥ 140 and DBP ≥ 90), were randomly selected from patient registers, and nine focus group discussions were conducted with a total 34 patients. Inductive codes were developed separately for the two groups, prior to analyzing key thematic ideas with smaller sub-categories. RESULTS: Affordability of antihypertensive medication and access to care emerged as the most important barriers. Fee subsidies for treatment and medication, along with health insurance, were mentioned as potential solutions to enhance access and adherence. Patient education and quality of physician counseling were mentioned by both providers and patients as major barriers to medication adherence, as most patients were unaware of their HT and often took medications only when symptomatic. Use of local herbal medicines was mentioned as an alternative to medications, as they were inexpensive, available, and culturally acceptable. Patient recommendations for improving adherence included community-based distribution of refills, SMS text reminders, and family support. Reliance on religious leaders over healthcare providers emerged as a potential means to promote adherence in some discussions. CONCLUSIONS: Effective management of hypertensive patients for medication adherence will require several context-specific measures. These include policy measures addressing financial access, with medication subsidies for the poor and accessible distribution systems for medication refill; physician measures to improve health provider counseling for patient centric care; and patient-level strategies with reminders for medication adherence in low resource settings.

Specialty Mediated 30-Day Complications in First Rib Resection for Thoracic Outlet Syndrome.

BACKGROUND: Thoracic outlet syndrome (TOS) takes on heterogenous upper extremity manifestations depending on whether the artery, vein or brachial plexus is primarily compressed. As a result of these variable vascular and neurogenic symptoms, these patients present to surgeons of various training backgrounds for surgical decompression. Surgeon specialty is known to correlate with outcomes for numerous vascular procedures, but its role in TOS is unclear. In this work we examine the association of surgeon specialty with short-term outcomes following first rib resection (FRRS) for TOS. METHODS: Using the American College of Surgeons National Surgical Quality Improvement Program database, 3,070 patients were identified who underwent FRRS for TOS between 2006-2017. The primary outcomes of the study were 30-d complications, including postoperative hemorrhage requiring transfusion, wound complications, pneumothorax and deep venous thrombosis. Arterial, venous, and neurogenic TOS were distinguished with ICD-9 and 10 codes while patient characteristics, provider specialty, and postoperative outcomes were classified through a combination of standard National Surgical Quality Improvement Program variables and ICD data. RESULTS: Most FRRS were performed by vascular surgeons (87.9%), general (6.9%) and thoracic surgeons (4.4%). The relative distribution of vascular TOS between the specialties was not significantly different, with non-vascular surgeons performing an equivalent amount of FRRS for arterial (1.1% versus 2.4%) and venous TOS (8.6% versus 9.1%, both P> 0.05). Patients who underwent FRRS with non-vascular surgeons experienced more frequent perioperative transfusions (3.2% versus 1.2%, P = 0.001) and wound infections (1.9% versus 0.8%, P= 0.04). On multivariable regression, patients undergoing FRRS for venous TOS were more likely to require blood transfusion (odds ratios:3.63, 95% CI 1.43-9.25). Patients operated on by surgeons whose specialty was not among the top three most common specialties performing FRRS had a 40% longer operative time (incidence rate ratios:1.42, 95% CI 1.15-1.74) as well as a significantly increased odds of requiring a transfusion (odds ratios:9.87, 95% CI 2.28-42.68). CONCLUSIONS: The significantly increased operative times and transfusion requirements associated with specialties who uncommonly perform FRRS suggest the role of surgeon experience and volume in this procedure may play more of a role than specialty training. These data also suggest that vascular TOS carries unique risks that should be kept in mind when performing FRRS.

Direct Comparison of Amino Acid and Salt Interactions with Double-Stranded and Single-Stranded DNA from Explicit-Solvent Molecular Dynamics Simulations.

Given the ubiquitous nature of protein-DNA interactions, it is important to understand the interaction thermodynamics of individual amino acid side chains for DNA. One way to assess these preferences is to perform molecular dynamics (MD) simulations. Here we report MD simulations of 20 amino acid side chain analogs interacting simultaneously with both a 70-base-pair double-stranded DNA and with a 70-nucleotide single-stranded DNA. The relative preferences of the amino acid side chains for dsDNA and ssDNA match well with values deduced from crystallographic analyses of protein-DNA complexes. The estimated apparent free energies of interaction for ssDNA, on the other hand, correlate well with previous simulation values reported for interactions with isolated nucleobases, and with experimental values reported for interactions with guanosine. Comparisons of the interactions with dsDNA and ssDNA indicate that, with the exception of the positively charged side chains, all types of amino acid side chain interact more favorably with ssDNA, with intercalation of aromatic and aliphatic side chains being especially notable. Analysis of the data on a base-by-base basis indicates that positively charged side chains, as well as sodium ions, preferentially bind to cytosine in ssDNA, and that negatively charged side chains, and chloride ions, preferentially bind to guanine in ssDNA. These latter observations provide a novel explanation for the lower salt dependence of DNA duplex stability in GC-rich sequences relative to AT-rich sequences.

Molecular Dynamics Simulations of 441 Two-Residue Peptides in Aqueous Solution: Conformational Preferences and Neighboring Residue Effects with the Amber ff99SB-ildn-NMR Force Field.

Understanding the intrinsic conformational preferences of amino acids and the extent to which they are modulated by neighboring residues is a key issue for developing predictive models of protein folding and stability. Here we present the results of 441 independent explicit-solvent MD simulations of all possible two-residue peptides that contain the 20 standard amino acids with histidine modeled in both its neutral and protonated states. (3)J(HNHα) coupling constants and δ(Hα) chemical shifts calculated from the MD simulations correlate quite well with recently published experimental measurements for a corresponding set of two-residue peptides. Neighboring residue effects (NREs) on the average (3)J(HNHα) and δ(Hα) values of adjacent residues are also reasonably well reproduced, with the large NREs exerted experimentally by aromatic residues, in particular, being accurately captured. NREs on the secondary structure preferences of adjacent amino acids have been computed and compared with corresponding effects observed in a coil library and the average ß-turn preferences of all amino acid types have been determined. Finally, the intrinsic conformational preferences of histidine, and its NREs on the conformational preferences of adjacent residues, are both shown to be strongly affected by the protonation state of the imidazole ring.