Telemedicine to a moving ambulance improves outcome after trauma in simulated patients.

BACKGROUND: Rural trauma victims often require prolonged transport by s with limited scopes of practice. We evaluated the impact of telemedicine (TM) to a moving ambulance on outcomes in simulated trauma patients. METHODS: This is an institutional review board approved, prospective double-blind study. Three trauma scenarios (blunt torso trauma, epigastric stab wound, and closed head injury) were created for a human patient simulator. Intermediate emergency medical technicians (EMTs; n = 20) managed the human patient simulator, in a moving ambulance. In the TM group, physicians (n = 12) provided consultation. In the non-TM group, EMTs communicated with medical control by radio, as necessary. We tabulated the fraction of 13 key signs, 5 pathologic processes, and 12 key interventions that were performed. Vital signs and Sao2 (%) were recorded. Data were compared using the Wilcoxon rank-sum test. RESULTS: Lowest Sao2 (84 ± 0.7 vs. 78 ± 0), lowest systolic blood pressure (70 ± 1 vs. 53 ± 1), and highest heart rate (144 ± 0.9 vs. 159 ± 0.5) were significantly improved in the TM group (p < 0.001). Recognition rates for key signs (0.96 ± 0.01 vs. 0.79 ± 0.05), processes (0.98 ± 0.02 vs. 0.75 ± 0.05), and critical interventions (0.92 ± 0.02 vs. 0.49 ± 0.03) were higher in the TM group (p < 0.003). EMTs were successfully guided through needle decompression procedures in 22 of 24 cases (zero in the non-TM group). CONCLUSION: TM to a moving ambulance improved the care of simulated trauma patients. Furthermore, procedurally naïve EMTs were able to perform needle thoracostomy and pericardiocentesis with TM guidance.

Detection of lipid pool, thin fibrous cap, and inflammatory cells in human aortic atherosclerotic plaques by near-infrared spectroscopy.

BACKGROUND: A method is needed to identify nonstenotic, lipid-rich coronary plaques that are likely to cause acute coronary events. Near-infrared (NIR) spectroscopy can provide information on the chemical composition of tissue. We tested the hypothesis that NIR spectroscopy can identify plaque composition and features associated with plaque vulnerability in human aortic atherosclerotic plaques obtained at the time of autopsy. METHODS AND RESULTS: A total of 199 samples from 5 human aortic specimens were analyzed by NIR spectroscopy. Features of plaque vulnerability were defined by histology as presence of lipid pool, thin fibrous cap (<65 microm by ocular micrometry), and inflammatory cell infiltration. An InfraAlyzer 500 spectrophotometer was used. Spectral absorbance values were obtained as log (1/R) data from 1100 to 2200 nm at 10-nm intervals. Principal component regression was used for analysis. An algorithm was constructed with 50% of the samples used as a reference set; blinded predictions of plaque composition were then performed on the remaining samples. NIR spectroscopy sensitivity and specificity for histological features of plaque vulnerability were 90% and 93% for lipid pool, 77% and 93% for thin cap, and 84% and 89% for inflammatory cells, respectively. CONCLUSIONS: NIR spectroscopy can identify plaque composition and features associated with plaque vulnerability in postmortem human aortic specimens. These results support efforts to develop an NIR spectroscopy catheter system to detect vulnerable coronary plaques in living patients.

Successful nonoperative management of the most severe blunt renal injuries: a multicenter study of the research consortium of New England Centers for Trauma.

IMPORTANCE: Severe renal injuries after blunt trauma cause diagnostic and therapeutic challenges for the treating clinicians. The need for an operative vs a nonoperative approach is debated. OBJECTIVE: To determine the rate, causes, predictors, and consequences of failure of nonoperative management (NOM) in grade IV and grade V blunt renal injuries (BRIs). DESIGN: Retrospective case series. SETTING: Twelve level I and II trauma centers in New England. PARTICIPANTS: A total of 206 adult patients with a grade IV or V BRI who were admitted between January 1, 2000, and December 31, 2011. MAIN OUTCOMES AND MEASURES: Failure of NOM, defined as the need for a delayed operation or death due to renal-related complications during NOM. RESULTS: Of 206 patients, 52 (25.2%) were operated on immediately, and 154 (74.8%) were managed nonoperatively (with the assistance of angiographic embolization for 25 patients). Nonoperative management failed for 12 of the 154 patients (7.8%) and was related to kidney injury in 10 (6.5%). None of these 10 patients had complications because of the delay in BRI management. The mean (SD) time from admission to failure was 17.6 (27.4) hours (median time, 7.5 hours; range, 4.5-102 hours), and the cause was hemodynamic instability in 10 of the 12 patients (83.3%). Multivariate analysis identified 2 independent predictors of NOM failure: older than 55 years of age and a road traffic crash as the mechanism of injury. When both risk factors were present, NOM failure occurred for 27.3% of the patients; when both were absent, there were no NOM failures. Of the 142 patients successfully managed nonoperatively, 46 (32.4%) developed renal-related complications, including hematuria (24 patients), urinoma (15 patients), urinary tract infection (8 patients), renal failure (7 patients), and abscess (2 patients). These patients were managed successfully with no loss of renal units (ie, kidneys). The renal salvage rate was 76.2% for the entire population and 90.3% among patients selected for NOM. CONCLUSIONS AND RELEVANCE: Hemodynamically stable patients with a grade IV or V BRI were safely managed nonoperatively. Nonoperative management failed for only 6.5% of patients owing to renal-related injuries, and three-fourths of the entire population retained their kidneys.

Anticoagulation management around percutaneous bedside procedures: is adjustment required?

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) and percutaneous dilatational tracheostomy (PDT) are frequently performed bedside in the intensive care unit. Critically ill patients frequently require anticoagulant (AC) and antiplatelet (AP) therapies for myriad indications. There are no societal guidelines proffering strategies to manage AC/AP therapies periprocedurally for bedside PEG or PDT. The aim of this study is to evaluate the management of AC/AP therapies around PEG/PDT, assess periprocedural bleeding complications, and identify risk factors associated with bleeding. METHODS: A retrospective, observational study of all adult patients admitted from October 2004 to December 2009 receiving a bedside PEG or PDT was conducted. Patients were identified by procedure codes via an in-hospital database. A medical record review was performed for each included patient. RESULTS: Four hundred fifteen patients were included, with 187 PEGs and 352 PDTs being performed. Prophylactic anticoagulation was held for approximately one dose before and two doses or less after the procedure. There was wide variation in patterns of holding therapy in patients receiving anticoagulation via continuous infusion. There were 19 recorded minor bleeding events, 1 (0.5%) with PEG and 18 (5.1%) with PDT, with no hemorrhagic events. No association was found between international normalized ratio, prothrombin time, or activated partial thromboplastin time values and bleed risk (p = 0.853, 0.689, and 0.440, respectively). Platelet count was significantly lower in patients with a bleeding event (p = 0.006). CONCLUSIONS: We found that while practice patterns were quite consistent in regard to the management of prophylactic anticoagulation, it varied widely in patients receiving therapeutic anticoagulation. It seems that prophylactic anticoagulation use did not affect bleed risk with PEG/PDT.

Phentolamine continuous infusion in a patient with pheochromocytoma.

PURPOSE: Use of continuous phentolamine infusion therapy for management of serious cardiovascular complications during adrenalectomy for pheochromocytoma is reported. SUMMARY: In preparation for surgical resection of a pheochromocytoma, a 38-year-old woman received outpatient oral therapy with the α-adrenergic-receptor blocker phenoxybenzamine for 25 days with the goal of reducing cardiovascular risks associated with catecholamine surge during surgery. Due to inappropriate dosage adjustment, however, outpatient phenoxybenzamine therapy did not achieve adequate α-adrenergic-receptor blockade; during the laparoscopic resection procedure, the woman developed severe hypertension, leading to cardiac arrest and discontinuation of the operation. After resuscitative measures, the patient was admitted to the surgical intensive care unit for mechanical ventilation, medical management (including intermittent bolus injections of phentolamine and a continuous i.v. infusion of esmolol for control of blood pressure and heart rate), and hemodynamic monitoring; despite those measures, cardiovascular instability persisted during the immediate postoperative period. The day after the abortive surgery attempt, a continuous infusion of phentolamine mesylate (1 mg/hr, adjusted hourly to achieve the blood pressure target) was initiated. Four days after initiation of continuous phentolamine infusion, the patient was deemed to be hemodynamically stable, and the surgery was successfully performed. CONCLUSION: A continuous infusion of phentolamine was used in a patient with pheochromocytoma to control perioperative hypertensive episodes during surgical adrenalectomy.

Near-infrared spectrometric determination of blood pH.

BACKGROUND: Reflectance near-infrared spectroscopy (600-2200 nm) can noninvasively probe deep into tissues. Blood is the predominant absorber of near-infrared light in biological tissues. We investigated the feasibility of using reflectance near-infrared spectroscopy to measure blood pH in vitro. METHODS: Reflectance near-infrared spectra (600-2200 nm) were obtained with a fiberoptic probe immersed in diluted human packed red blood cells maintained at 37 degrees C. Changes in pH (6.800-7.600) were induced by: (1) varying the partial pressure of carbon dioxide by the bubbling of mixtures of humidified carbon dioxide and nitrogen gas through the blood; and (2) adding 1 N HCl/NaOH. Humidified oxygen gas was bubbled through the blood to generate variations in oxygen saturation. After each titration of pH, the spectrum was recorded and blood was sampled for the measurement of: pH, pCO(2), and pO(2) using blood gas analysis; and hemoglobin concentration and oxygen saturation using co-oximetry. Samples from three separate pH titrations were combined (120 total samples) and analyzed using partial least-squares analysis to generate a mathematical model relating spectral changes to pH (calibration set). This model was then used to predict the pH of a set of 36 pH titrations (prediction set). RESULTS: Quantitative and qualitiative analyses of the spectra in the calibration set found that spectral changes in the wavelength range, 650-1050 nm, were directly related to changes in pH. First-derivative-treated spectra from the calibration set, analyzed using partial least-squares analysis, generated a mathematical model with a cross-validated r(2) of 0.939 and a standard error of calibration of 0.046 pH unit. When this model was applied to the prediction set, with an offset correction, the r(2) was 0.936 with a standard error of prediction of 0.050 pH unit. CONCLUSION: Blood pH can be predicted in vitro with clinical significance using reflectance near-infrared spectroscopy (650-1050 nm) within a standard error of 0.050 pH unit.