Dimitrios Theodorou

Evaluation of Penetrating Injuries of the Neck: Prospective Study of 223 Patients

Abstract. The objective of this study was to assess the role of clinical examination, angiography, color flow Doppler imaging, and other diagnostic tests in identifying injuries to the vascular or aerodigestive structures in patients with penetrating injuries to the neck. A prospective study was made of patients with penetrating neck injuries. All patients had a careful physical examination according to a written protocol. Stable patients underwent routine four-vessel angiography and color flow Doppler imaging. Esophagography and endoscopy were performed for proximity injuries. The sensitivity, specificity, and predictive values of physical examination, color flow Doppler studies, and other diagnostic tests were assessed during the evaluation of vascular and aerodigestive tract structures in the neck. Altogether 223 patients were entered in the study. After physical examination 176 patients underwent angiography and 99 of them underwent color flow Doppler imaging. Angiographic abnormalities were seen in 34 patients for an incidence of 19.3%, but only 14 (8.0%) required treatment. Color flow Doppler imaging was performed on 99 patients with a sensitivity of 91.7%, specificity 100%, positive predictive value (PPV) 100%, and negative predictive value (NPV) 99%. These values were all 100% when only injuries requiring treatment were considered. None of the 160 patients without clinical signs of vascular injury had serious vascular trauma requiring treatment (NPV 100%), although angiography in 127 showed 11 vascular lesions not requiring treatment. “Hard” signs on clinical examination (large expanding hematomas, severe active bleeding, shock not responding to fluids, diminished radial pulse, bruit) reliably predicted major vascular trauma requiring treatment. Among 34 of the 223 total patients (15.2%) admitted with “soft” signs, 8 had angiographically detected injuries, but only one required treatment. An esophagogram was performed on 98 patients because of proximity injuries (49 patients) or suspicious clinical signs (49 patients), and two of them showed esophageal perforations. None of the 167 patients without clinical signs of esophageal trauma had an esophageal injury requiring treatment. It was concluded that physical examination is reliable for identifying those patients with penetrating injuries of the neck who require vascular or esophageal diagnostic studies. Color flow Doppler imaging is a dependable alternative to angiography. An algorithm for the initial assessment of neck injuries is suggested.

Radiographic cervical spine evaluation in the alert asymptomatic blunt trauma victim : much ado about nothing

OBJECTIVE To evaluate the hypothesis that alert nonintoxicated trauma patients with negative clinical examinations are at no risk of cervical spine injury and do not need any radiographic investigation. DESIGN Prospective study. SETTING A university-affiliated teaching county hospital. PATIENTS Five hundred and forty-nine consecutive alert, oriented, and clinically nonintoxicated blunt trauma victims with no neck symptoms. RESULTS All patients had negative clinical neck examinations. After radiographic assessment, no cervical spine injuries were identified. Less than half the patients could be evaluated adequately with the three standard initial views (anteroposterior, lateral, and odontoid). All the rest needed more radiographs and/or computed tomographic scans. A total of 2,27 cervical spine radiographs, 78 computed tomographic scans and magnetic resonance imagings were performed. Seventeen patients stayed one day in the hospital for no other reason but radiographic clearance of an asymptomatic neck. The total cost for x-rays and extra hospital days was

Mortality and prognostic factors in penetrating injuries of the aorta.

242,000. These patients stayed in the collar for an average of 3.3 hours (range, 0.5-72 hours). There was never an injury missed. CONCLUSIONS Clinical examination alone can reliably assess all blunt trauma patients who are alert, nonintoxicated, and report no neck symptoms. In the absence of any palpation or motion neck tenderness during examination, the patient may be released from cervical spine precautions without any radiographic investigations.

Transcervical gunshot injuries: mandatory operation is not necessary.

PURPOSE This study was designed to investigate the epidemiology and prognostic factors determining survival in penetrating injuries of the aorta. PATIENTS AND METHODS This was a retrospective analysis of all patients with penetrating aortic injuries, admitted to a large, level I trauma center. The following factors were analyzed for their role in determining survival: mechanism of injury, anatomical site of the aortic injury, initial blood pressure on admission, need for emergency room thoracotomy, and the introduction of a dedicated trauma program with an attending surgeon in-house. RESULTS There were 93 patients with penetrating aortic injuries over a 5-year period. The abdominal aorta was injured in 67 patients (72%) and the thoracic aorta in 26 (28%). Most of the victims (82.5%) were admitted in shock and 41% had an unrecordable blood pressure on admission. Victims with injury to the thoracic aorta were more likely to have an unrecordable blood pressure on admission than patients with abdominal aortic injuries (73% vs 28.4%), and more likely to require an emergency room thoracotomy (76.9% vs 20.9%). Thirty-four patients (36.6%) required an emergency room thoracotomy and there were no survivors. The overall mortality was 80.6% (87.5% for gunshot injuries, 64.7 % for knife injuries). Patients with abdominal aortic injuries were three times more likely to survive than those with thoracic aortic injuries (23.9% vs 7.7%). The introduction of a dedicated trauma program, which resulted in significant reduction of mortality in other types of severe trauma, had no effect on the outcome in aortic injuries. CONCLUSIONS Penetrating aortic injuries still have a very high mortality rate with no improvement in survival despite improved trauma services. Injury to the thoracic aorta, gunshot wounds, unrecordable blood pressure on admission, and the need for emergency room thoracotomy, are important predictors of high mortality.

Complications and Nonclosure Rates of Fasciotomy for Trauma and Related Risk Factors

BACKGROUND It has been suggested that all transcervical gunshot wounds should be explored surgically because of the high incidence of injuries to vital structures. The present prospective study investigated the clinical presentation, the role of various diagnostic investigations, and the need for surgery in patients with transcervical gunshot injuries. METHODS Ninety-seven patients sustained gunshot injuries to the neck and 33 of them (34%) were transcervical. All victims were assessed clinically according to a written protocol and subsequently were evaluated angiographically, and, in the appropriate case, by means of endoscopy and esophagography. RESULTS Overall, 24 (73%) of the 33 patients with transcervical gunshot wounds had injuries to cervical structures. Vascular injuries were found in 48%, spinal cord injuries in 24%, and aerodigestive tract injuries in 6% of patients with transcervical injuries. In the 64 patients without midline crossing, the incidence of cervical structure injuries was 31%. Despite the high incidence of injuries to cervical structures in transcervical wounds, only 21% of the patients had a therapeutic operation. The overall mortality was 3%. There were no in-hospital deaths or local complications in the nonoperatively managed group. CONCLUSIONS The results of the present study do not support the current recommendations of mandatory operation for all transcervical gunshot wounds. A careful clinical examination combined with the appropriate diagnostic investigations should determine the treatment modality. About 80% of these patients can safely be managed nonoperatively.

Infections in a surgical intensive care unit of a university hospital in Greece.

Abstract. The objective of this study was to identify risk factors for the development of complications and unsatisfactory skin closure following fasciotomy for trauma. Risk factors included in the study are prolonged time from injury to fasciotomy, type of fasciotomy, site of injury, and kind of underlying injury. The study was a retrospective analysis of 100 consecutive fasciotomies done for trauma over a period of 38 months (December 1991 to January 1995) in a “level I” trauma center at a university-affiliated county teaching hospital. Ninety-four patients were eligible for analysis, 29 of whom (31%) developed complications at the fasciotomy site. The risk was increased for lower extremity versus upper extremity (34.3% versus 20.8%), prophylactic versus therapeutic (42.0% versus 24.6%), late (>8 hours) versus early (37% versus 25%), and vascular versus musculoskeletal (38.8% versus 22.2%) trauma cases. The same risk factors negatively influenced the ability to close the skin primarily. The four subgroups defined by vascular/nonvascular injury and upper/lower extremity site had significantly different nonclosure rates (p = 0.043). The rate was highest among the vascular/lower extremity group (60.5%) and lowest among the nonvascular/upper extremity group (15.4%). We concluded that fasciotomies in lower extremities, the presence of underlying vascular injuries, fasciotomies performed prophylactically, and a time between the injury and fasciotomy of more than 8 hours are associated with an increased risk for local complications. The same factors are associated with an increased need for skin grafting the wound.

The Effects of Vasopressors on Perfusion of Gastric Graft after Esophagectomy. An Experimental Study

OBJECTIVES We aimed to evaluate the clinical and microbiological characteristics of the patients who developed an infection in our surgical intensive care unit (SICU). METHODS This was a prospective study of all patients who sustained an ICU-acquired infection from 2002 to 2004. RESULTS Among 683 consecutive SICU patients, 123 (18.0%) developed 241 infections (48.3 infections per 1000 patient-days). The mean age of patients was 66.7+/-3.8 years, the mean APACHE II score (acute physiology and chronic health evaluation) on SICU admission was 18.2+/-2.4, and the mean SOFA score (sepsis-related organ failure assessment) at the onset of infection was 8.8+/-2. Of the study patients, 51.2% were women. Infections were: bloodstream (36.1%), ventilator-associated pneumonia (VAP; 25.3%, 20.3/1000 ventilator-days), surgical site (18.7%), central venous catheter (10.4%, 7.1/1000 central venous catheter-days), and urinary tract infection (9.5%, 4.6/1000 urinary catheter-days). The most frequent microorganisms found were: Acinetobacter baumannii (20.3%), Pseudomonas aeruginosa (15.7%), Candida albicans (13.2%), Enterococcus faecalis (10.4%), Klebsiella pneumoniae (9.2%), Enterococcus faecium (7.9%), and Staphylococcus aureus (6.7%). High resistance to the majority of antibiotics was identified. The complication and mortality rates were 58.5% and 39.0%, respectively. Multivariate analysis identified APACHE II score on admission (odds ratio (OR) 4.63, 95% confidence interval (CI) 2.69-5.26, p=0.01), peritonitis (OR 1.85, 95% CI 1.03-3.25, p=0.03), acute pancreatitis (OR 2.27, 95% CI 1.05-3.75, p=0.02), previous aminoglycoside use (OR 2.84, 95% CI 1.06-5.14, p=0.03), and mechanical ventilation (OR 3.26, 95% CI: 2.43-6.15, p=0.01) as risk factors for infection development. Age (OR 1.16, 95% CI 1.01-1.33, p=0.03), APACHE II score on admission (OR 2.53, 95% CI 1.77-3.41, p=0.02), SOFA score at the onset of infection (OR 2.88, 95% CI 1.85-4.02, p=0.02), and VAP (OR 1.32, 95% CI 1.04-1.85, p=0.03) were associated with mortality. CONCLUSIONS Infections are an important problem in SICUs due to high incidence, multi-drug resistance, complications, and mortality rate. In our study, APACHE II score on admission, peritonitis, acute pancreatitis, previous aminoglycoside use, and mechanical ventilation were identified as risk factors for infection development, whereas age, APACHE II score on admission, SOFA score at the onset of infection, and VAP were associated with mortality.

Comparison of ISO-GUM and Monte Carlo methods for the evaluation of measurement uncertainty: Application to direct cadmium measurement in water by GFAAS

AimsTo evaluate the impact of the perioperative administration of norepinephrine on the perfusion of the esophageal graft.MethodsThis is an experimental study. Six swine underwent transhiatal esophagectomy; the stomach was used to replace the resected esophagus. We provoked hemorrhagic shock to the animals and then we administered noradrenaline to restore the blood pressure. We monitored the graft perfusion perioperatively using the technique of microdialysis.ResultsIn all animals, the graft experienced severe hypoperfusion after the administration of noradrenaline that was statistically significant.ConclusionsOur data support the hypothesis that norepinephrine should be used with extreme caution in the perioperative setting after esophagectomy. Further studies, however, will be required to evaluate the clinical significance of this finding.

pERK activation in esophageal carcinomas: Clinicopathological associations

The propagation stage of uncertainty evaluation, known as the propagation of distributions, is in most cases approached by the GUM (Guide to the Expression of Uncertainty in Measurement) uncertainty framework which is based on the law of propagation of uncertainty assigned to various input quantities and the characterization of the measurand (output quantity) by a Gaussian or a t-distribution. Recently, a Supplement to the ISO-GUM was prepared by the JCGM (Joint Committee for Guides in Metrology). This Guide gives guidance on propagating probability distributions assigned to various input quantities through a numerical simulation (Monte Carlo Method) and determining a probability distribution for the measurand. In the present work the two approaches were used to estimate the uncertainty of the direct determination of cadmium in water by graphite furnace atomic absorption spectrometry (GFAAS). The expanded uncertainty results (at 95% confidence levels) obtained with the GUM Uncertainty Framework and the Monte Carlo Method at the concentration level of 3.01 μg/L were ±0.20 μg/L and ±0.18 μg/L, respectively. Thus, the GUM Uncertainty Framework slightly overestimates the overall uncertainty by 10%. Even after taking into account additional sources of uncertainty that the GUM Uncertainty Framework considers as negligible, the Monte Carlo gives again the same uncertainty result (±0.18 μg/L). The main source of this difference is the approximation used by the GUM Uncertainty Framework in estimating the standard uncertainty of the calibration curve produced by least squares regression. Although the GUM Uncertainty Framework proves to be adequate in this particular case, generally the Monte Carlo Method has features that avoid the assumptions and the limitations of the GUM Uncertainty Framework.

Advanced Trauma Life Support certified physicians in a non trauma system setting: is it enough?

MAPK (mitogen-activated protein kinase) pathway is considered a control regulator in various malignant tumors but its role in esophageal carcinomas remains elusive. In our study, we examined the possible prognostic significance of MAPK pathway in human esophageal cancer. We searched for mutations in exons 18-21 of EGFR gene, codons 12 and 13 of K-RAS gene and exon 15 of B-RAF gene by high resolution melting analysis (HRMA) and pyrosequencing in 44 esophageal carcinomas. Immunohistochemistry was performed in 29 cases in order to evaluate expression levels of pERK (extracellular-signal regulated kinase). In one laser microdissected squamous cell carcinoma, a somatic K-RAS mutation at codon 12 was detected, whereas none of the cases displayed mutations in EGFR and B-RAF genes. Elevated nuclear as well as cytoplasmic pERK expression (100% and 62% of cases respectively) was observed independently of EGFR and B-RAF mutational status. Increasing pERK nuclear and cytoplasmic expression as well as the intensity of nuclear staining was found to be significantly correlated with tumor grade in univariate and multivariate statistical analysis. Our findings depict the presence of activated ERK despite the low frequency of upstream alterations, implicating ERK activation in the acquisition of a more aggressive phenotype in esophageal cancer.