Diagnostic accuracy of thermal, hydration, and heart rate assessments in discriminating positive acute kidney injury risk following physical work in the heat.

Occupational heat stress increases the risk of acute kidney injury (AKI). This study presents a secondary analysis to generate novel hypotheses for future studies by investigating the diagnostic accuracy of thermal, hydration, and heart rate assessments in discriminating positive AKI risk following physical work in the heat in unacclimatized individuals. Unacclimatized participants (n = 13, 3 women, age: ∼23 years) completed four trials involving 2 h of exercise in a 39.7 ± 0.6 °C, 32 ± 3% relative humidity environment that differed by experimental manipulation of hyperthermia (i.e., cooling intervention) and dehydration (i.e., water drinking). Diagnostic accuracy was assessed via receiver operating characteristic curve analysis. Positive AKI risk was identified when the product of concentrations insulin-like growth factor binding protein 7 and tissue inhibitor of metalloproteinase-2 [IGFBP7∙TIMP-2] exceeded 0.3 (ng∙mL-1)2∙1000-1. Peak absolute core temperature had the acceptable discriminatory ability (AUC = 0.71, p = 0.009), but a relatively large variance (AUC 95% CI: 0.57-0.86). Mean body temperature, urine specific gravity, urine osmolality, peak heart rate, and the peak percent of both maximum heart rate and heart rate reserve had poor discrimination (AUC = 0.66-0.69, p ≤ 0.051). Mean skin temperature, percent change in body mass and plasma volume, and serum sodium and osmolality had no discrimination (p ≥ 0.072). A peak increase in mean skin temperature of >4.7 °C had a positive likelihood ratio of 11.0 which suggests clinical significance. These data suggest that the absolute value of peak core temperature and the increase in mean skin temperature may be valuable to pursue in future studies as a biomarker for AKI risk in unacclimatized workers.

Fitness characteristics of a suburban special weapons and tactics team.

Special Weapons and Tactics (SWAT) operators are specialized law enforcement officers who traditionally perform their duties with higher anticipated workloads because of additional body armor, weapons, and equipment used for enhanced operations and protection. This elevated workload increases the need for SWAT operators to improve or maintain their physical fitness to consistently perform routine operations. Typical tasks require trunk rotation, overhead upper extremity use, upper and lower body strength use, and long waiting periods followed by explosive movements while wearing additional equipment. Eleven male SWAT operators from 1 SWAT team performed flexibility, strength, power, and aerobic capacity tests and a variety of job-related tasks. Data were compared with age- and gender-based normative data. Fitness testing revealed that officers ranked high on tests of muscular strength (leg strength, 90th percentile; bench press, 85th percentile); however, body composition (55th percentile), core body strength, and flexibility ranked lower. Furthermore, aerobic capacity and muscular power had a wide range of scores and were also not ideal to support maximal performance during routine operations. These data can assist exercise specialists choose fitness programs specifically for job-related tasks of SWAT operators when creating fitness programs. Fitness programming for law enforcement should focus on improving aerobic fitness, flexibility, core strength, and muscular power while maintaining muscular strength to meet the needs of these specialized officers.

Frequency and follow-up of incidental findings on trauma computed tomography scans: experience at a level one trauma center.

OBJECTIVES: Incidental findings found on computed tomography (CT) scan during the Emergency Department evaluation of trauma patients are often benign, but their presence must always be communicated to patients, who should be referred for follow-up care. Our objective was to quantify the frequency of these incidental CT findings in trauma patients. A secondary goal was to determine how often these lesions were communicated to patients and how often patients were referred for follow-up. METHODS: We performed a retrospective chart review of 500 consecutive patients presenting as trauma activations. Subjects received head, chest, or abdomen/pelvis CT scans at our hospital. Patients were identified using our trauma registry. Final CT reports were examined and discharge summaries were reviewed for basic demographics. Scans with incidental findings prompted detailed secondary review of discharge summaries to determine follow-up. Investigators reviewed incidental findings and classified them into three groups by clinical importance, using predetermined criteria. RESULTS: Of the 500 patient charts identified for review, 480 (96%) were available, yielding 1930 CT reports for analysis. Incidental findings were noted in 211 of 480 (43%) patients and on 285 (15%) of the 1930 CT studies performed for the 480 patients. Of available patient records, only 27% of patient charts had mention of the finding in the discharge summary, had documentation of an in-hospital workup, or had documentation of a referral for follow-up. Most-concerning lesions, such as suspected malignancies or aortic aneurysms, accounted for 15% of all incidental findings and were referred for follow-up in only 49% of cases. CONCLUSIONS: Incidental findings were noted in 15% of trauma CT scans. Follow-up was poor, even for potentially serious findings. Further studies should examine the long-term outcome of patients with these findings.

Predictors of ROSC in witnessed aeromedical cardiac arrests.

INTRODUCTION: Aeromedical agencies are used routinely to transport critically ill patients to specialty centers. The characteristics of patients suffering a cardiac arrest during transport by aeromedical flight personnel are not well-documented. We completed a retrospective analysis of aeromedical patient care records in order to describe the pre-arrest characteristics and the return of spontaneous circulation (ROSC) in this subset of patients. MATERIALS AND METHODS: A retrospective chart reviews of patients suffering from cardiac arrest while being treated by a single aeromedical transport service between 1998 and 2000. Crew configurations were paramedic/nurse or paramedic/physician. Data were directly abstracted by the authors and descriptive data of patient demographics, vital signs and medical history were obtained. Data were separated into medical and traumatic arrests and analyzed by chi2- and t-test. Logistic regression analyses were performed to determine predictors of ROSC. RESULTS: During the 24-month interval, 12,140 patient transports occurred. Of these, 134 cardiac arrests occurred (1.1%) and are reviewed. Of these, 57 were medical arrests and 76 were traumatic arrests. Nine medical arrests and 37 traumatic arrests were excluded as the patient was in cardiac arrest before crew arrival. In the medical arrest cohort, the presence of a peripheral i.v. before crew arrival and initial rhythm of arrest were associated with ROSC at destination (p=0.05). In the traumatic arrest cohort, patients with lower diastolic blood pressures had a trend toward lower rates of ROSC (p=0.06). CONCLUSION: Cardiac arrest during aeromedical transport is infrequent. Patients with poor i.v. access are less likely to experience ROSC should they experience a cardiac arrest. Patients with traumatic injury and diastolic hypotension may be less likely to survive cardiac arrest during transport.

Comparison of the Ferno Scoop Stretcher with the long backboard for spinal immobilization.

OBJECTIVES: Spinal immobilization is essential in reducing risk of further spinal injuries in trauma patients. The authors compared the traditional long backboard (LBB) with the Ferno Scoop Stretcher (FSS) (Model 65-EXL). They hypothesized no difference in movement during application and immobilization between the FSS and the LBB. METHODS: Thirty-one adult subjects had electromagnetic sensors secured over the nasion (forehead) and the C3 and T12 spinous processes and were placed in a rigid cervical collar, with movement recorded by a goniometer (a motion analysis system). Subjects were tested on both the FSS and the LBB. The sagittal flexion, lateral flexion, and axial rotation were recorded during each of four phases: 1) baseline, 2) application (logroll onto the LBB or placement of the FSS around the patient), 3) secured logroll, and 4) lifting. Comfort and perceived security also were assessed on a visual analog scale. RESULTS: There was approximately 6-8 degrees greater motion in the sagittal, lateral, and axial planes during the application of the LBB compared with the FSS (both p < 0.001). No difference was found during a secured logroll maneuver. The FSS induced more sagittal flexion during the lift than the LBB (p < 0.001). The FSS demonstrated superior comfort and perceived security. CONCLUSION: The FSS caused significantly less movement on application and increased comfort levels. Decreased movement using the FSS may reduce the risk of further spinal cord injury.

Feasibility of sternal intraosseous access by emergency medical technician students.

OBJECTIVE: Emergency medical technician-basic (EMT-B) providers are not trained to establish vascular or intraosseous (IO) access on critically ill patients. This study was conducted to examine the feasibility of training EMT-B students to correctly place a commercial sternal IO infusion device (FAST-1). METHODS: Twenty-nine EMT-B students attended a two-hour training session. Subjects were subsequently tested in FAST-1 application using a modified resuscitation mannequin permitting IO needle deployment. Two observers assessed correct IO application and technique. Results were analyzed using descriptive statistics (binomial proportions and medians with 95% confidence intervals). Inter-rater agreement of observations was evaluated using kappa statistics and intraclass correlation coefficients (ICCs). RESULTS: Inter-rater agreement ranged from fair to excellent (kappa = 0.37-1.00) for all parameters except sternal notch identification (kappa = -0.03). Reliabilities of elapsed times were good (ICC = 0.83, 0.31). Correct identification of the sternal notch was accomplished by 28 of 29 students (96.6%; 95% CI: 82.2-99.9%). Correct application of the IO target patch was achieved by 29 of 29 (100.0%; 88.1-100.0%). First-attempt successful IO needle deployment was achieved by 16 of 29 (55.2%; 35.7-73.6%). Overall successful IO needle deployment within four attempts was achieved by 27 of 29 (93.1%; 77.2-99.2%). The protective dome was correctly applied by 27 of 29 (93.1%; 77.2-99.2%). The median time to needle deployment was 27.5 seconds (95% CI: 24-31). The median time to dome placement was 50 seconds (95% CI: 42-55). CONCLUSIONS: EMT-B students with minimal training demonstrated limited success with applying a commercial sternal IO device. Clinical application by EMT-Bs on critically ill patients may be possible with more intensive training.

Ventricular fibrillation scaling exponent can guide timing of defibrillation and other therapies.

BACKGROUND: The scaling exponent (ScE) of the ventricular fibrillation (VF) waveform correlates with duration of VF and predicts defibrillation outcome. We compared 4 therapeutic approaches to the treatment of VF of various durations. METHODS AND RESULTS: Seventy-two swine (19.5 to 25.7 kg) were randomly assigned to 1 of 9 groups (n=8 each). VF was induced and left untreated until the ScE reached 1.10, 1.20, 1.30, or 1.40. Animals were treated with either immediate countershock (IC); 3 minutes of CPR before the first countershock (CPR); CPR for 2 minutes, then drugs given with 3 more minutes of CPR before the first shock (CPR-D); or drugs given at the start of CPR with 3 minutes of CPR before the first shock (Drugs+CPR). Return of spontaneous circulation (ROSC) and 1-hour survival were analyzed with chi2 and Kaplan-Meier survival curves. IC was effective when the ScE was low but had decreasing success as the ScE increased. No animals in the 1.30 or 1.40 groups had ROSC from IC (0 of 16). CPR did not improve first shock outcome in the 1.20 CPR group (3 of 8 ROSC). Kaplan-Meier survival analyses indicated that IC significantly delayed time to ROSC in both the 1.3 (P=0.0006) and the 1.4 (P=0.005) groups. CONCLUSIONS: VF of brief to moderate duration is effectively treated by IC. When VF is prolonged, as indicated by an ScE of 1.3 or greater, IC was not effective and delayed time to ROSC. The ScE can help in choosing the first intervention in the treatment of VF.