Search PubMed⌕ Search

Biomedical subjects

D Demetriades

Publications and source records attributed to D Demetriades.

At least 109 records · Page 6Linked to original sources
PubMed1997

Selective nonoperative management of gunshot wounds of the anterior abdomen.

OBJECTIVE: To investigate the role of selective nonoperative management of gunshot wounds to the abdomen. DESIGN: A prospective, protocol-guided study including all gunshot wounds of the anterior abdomen. PATIENTS AND METHODS: The patients were assessed and managed according to a written protocol. Patients with hemodynamic instability or peritonitis or associated spinal cord or head injury or requiring a general anesthetic for an extra-abdominal injury were managed by laparotomy. The test of the patients were selected for initial nonoperative management with serial physical examinations. RESULTS: During a 16-month period, 309 patients with gunshot wounds of the anterior abdomen were treated. Eighteen patients in extremis (5.8%) underwent an emergency department-performed thoracotomy. Another 185 patients (59.9%) met the criteria for operation and underwent a laparotomy. The incidence of nontherapeutic operations was 2.2%, and that of negative operations was 8.6%. One hundred six patients (34.3%) were selected for observation. Fourteen of the initially observed patients underwent a late operation, but it was therapeutic in only 5. Overall, 92 patients (29.8%) were successfully managed nonoperatively. The overall sensitivity of the initial physical examination was 97.1%. The estimated bullet trajectory was not reliable in identifying the need for operation because of 224 patients with likely peritoneal penetration only 169 (75.4%) had significant injuries requiring surgical repair. CONCLUSION: In the appropriate environment, many civilian abdominal gunshot wounds can be managed non-operatively.

Abdominal Injuries↗
PubMed1997

Gunshot wounds to the buttocks: predicting the need for operation.

BACKGROUND: Gunshot wounds to the buttocks may cause significant intra-abdominal injuries. Policies of aggressive abdominal exploration or extensive diagnostic testing have been suggested to avoid delays in treatment and consequent morbidity. Our group has recently suggested that clinical examination is a safe and reliable tool for triaging patients with anterior and posterior abdominal gunshot wounds. OBJECTIVE: This study was undertaken to test the hypothesis that patients with gunshot wounds to the buttocks can be managed selectively on the basis of clinical findings. SETTING: A large academic Level I trauma center was the setting for this study. PATIENTS AND METHODS: Fifty-nine consecutive patients, suffering from gunshot wounds to the buttocks with potential retroperitoneal trajectories, were managed during a 12-month period in our center. RESULTS: Based on clinical findings, 19 (32.2 percent) patients were operated on, with significant intra-abdominal injuries in 17 (28.8 percent). The remaining 40 (67.8 percent) patients were successfully observed. There were no missed injuries or delays in diagnosis. Sensitivity and specificity of clinical examination for identifying significant intra-abdominal injury was 100 percent and 95.3 percent, respectively. CONCLUSION: Clinical examination is a safe method for selecting patients with gunshot wounds to the buttocks for nonoperative treatment.

Abdominal Injuries↗
PubMed1997

Evaluation of penetrating injuries of the neck: prospective study of 223 patients.

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.

Algorithms↗
PubMed1997

Patterns of injury in victims of urban free-falls.

The objective of this study was to identify the patterns of injury in urban free-fall victims so as to establish guidelines of management. This prospective study at an academic level I trauma center included 187 consecutive patients who presented to our trauma center during a 9-month period (September 1994 to June 1995) after a fall from a height of 5 to 70 feet. Only three falls were from heights of more than 40 feet. Of these patients, 116 (65.1%) suffered significant trauma. Fractures were the most common injuries, accounting for 76.2% of all injuries. Spinal fractures were detected in 37 patients and were associated with neurologic deficits in 7. Intraabdominal injuries occurred in 11 patients, requiring operative intervention in 9 of them. Solid organ lacerations prevailed, but small bowel perforation and bladder rupture were present in one case each. A significant retroperitoneal hematoma was detected in only one case and a thoracic aortic rupture in one more. The height of the fall correlated highly with the incidence of intoxication and severity of injury, the need for operation, the length of hospitalization, and mortality. Most urban free-falls occur from moderate heights. The spinal column is frequently injured and therefore should be thoroughly assessed clinically and radiographically in all fall victims. Intraabdominal organ injuries are much more common than retroperitoneal ones. Thus the abdominal cavity should be the primary target of aggressive workup in hemodynamically unstable patients. The height of the fall is a good predictor of injury severity and outcome prognosis.

Accidental Falls↗
PubMed1997

A unified approach to the surgical exposure of pancreatic and duodenal injuries.

One of the greatest challenges to any surgeon is the intraoperative detection and surgical management of duodenal and pancreatic injuries. A uniform approach to the surgical exposure of all suspected pancreatic and duodenal injuries will decrease their morbidity and mortality by identifying all injuries. Proper intraoperative assessment and grading will help with procedure selection from the broad surgical armamentarium available to manage these injuries.

Duodenum↗
PubMed1997

A selective approach to the management of gunshot wounds to the back.

BACKGROUND: Gunshot wounds to the back with retroperitoneal trajectories have been traditionally managed under the same guidelines as anterior gunshot wounds. Recent work has suggested that selective nonoperative management of anterior abdominal gunshot wounds is safe. The role of this policy in gunshot wounds to the back, where retroperitoneal organ injuries may be more difficult to detect clinically, has not been investigated. OBJECTIVE: To examine if selective nonoperative management based on clinical assessment is a safe alternative to mandatory exploration for gunshot wounds to the back. DESIGN: Prospective study. SETTING: Large-volume level-1 university affiliated trauma center. PATIENTS AND METHODS: Two hundred and three consecutive patients with gunshot wounds to the back were managed according to a protocol during a 12-month period. Patients with hemodynamic instability or peritonitis underwent urgent operation. The rest of the patients were observed with careful serial clinical examinations. RESULTS: Eleven patients underwent an emergency room thoracotomy and were excluded. Four more patients were operated upon, despite the absence of abdominal findings, because of associated spinal cord injuries (2 patients), inability to observe due to need for repair of an associated peripheral vascular injury (1 patient), and participation in another protocol of aggressive evaluation of asymptomatic patients with suspected diaphragmatic injuries (1 patient). Of the remaining 188 patients, 58 (31%) underwent laparotomy (56 therapeutic, 2 negative) and 130 (69%) were initially observed owing to negative clinical examination. Following the development of increasing abdominal tenderness, 4 of these 130 (3%) underwent delayed explorations, which were all nontherapeutic. The sensitivity and specificity of initial clinical examination in detecting significant intraabdominal injuries were 100% and 95%, respectively. CONCLUSIONS: Mandatory laparotomy is not necessary for gunshot wounds of the back. Clinical examination is a safe method of selecting patients for nonoperative management. An observation period of 24 hours is adequate for patients with no abdominal symptoms.

Abdominal Injuries↗
PubMed1997

Penetrating esophageal injuries: time interval of safety for preoperative evaluation--how long is safe?

OBJECTIVES: This study was performed to assess the experience with penetrating esophageal injuries of an urban Level I trauma center and to attempt to correlate the time to establish a diagnosis with outcome including death, surgical intensive care unit length of stay, and esophageal-related complications. METHODS: Retrospective study over a 72-month period at a single institution comparing age, admission blood pressure, Revised Trauma Score (RTS), Injury Severity Score (ISS), mechanism and anatomic location of injury, and time interval from admission to the operating room (OR) between nonsurvivors and survivors. Patients who survived to reach the operating room were divided into two groups: those who went immediately to the operating room (no preoperative evaluation) and those who underwent diagnostic studies to identify their injuries (preoperative evaluation). Data analysis was done of the same parameters plus average number of associated injuries, complications, and intensive care unit length of stay. Statistical methods used univariate analysis (Fisher's exact test and Student's t test). RESULTS: Forty-three patients were identified with penetrating esophageal injuries and had the following characteristics: 36 males (84%) and 7 females (16%); mean RTS, 9.39; mean ISS, 28.1; mean time interval to OR, 9.8 hours. Associated injuries occurred with 42 patients (98%). The overall complication rate was 14 of 32 (44%), and the overall mortality was 11 of 43 (26%). Corrected mortality was 22%. Differences were noted between nonsurvivors and survivors in the following parameters: admission blood pressure < 90, 11 of 11 versus 3 of 29 (p < 0.001); RTS, 2.364 versus 11.406 (p < 0.001); ISS, 45 versus 21 (p < 0.001); time interval from admission to OR, 18.3 minutes versus 9.8 hours (p < 0.05). Thirty-six patients survived to reach the operating room, 18 in the no preoperative evaluation group and 17 in the preoperative evaluation group. No statistically significant differences were noted between these two groups in the following parameters: age, RTS, ISS, admission blood pressure, anatomic location of injury, number of associated injuries, or intensive care unit length of stay. Average length of time to the operating room was 16.7 hours in the preoperative evaluation group and 1.4 hours in the no preoperative evaluation group (p < 0.001). Twelve complications (all esophageal-related) occurred among seven patients in the preoperative evaluation group, and seven complications (five esophageal-related) occurred among seven patients in the no preoperative evaluation group. Because of the small sample size, this failed to reach a statistical difference (p < 0.05). CONCLUSIONS: Esophageal injuries carry a high morbidity and mortality. Although no definite conclusion can be drawn because of the small sample size, there does appear to be an increased morbidity associated with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, the rapid diagnosis and definitive repair of esophageal injury should be made a high priority.

Adult↗
PubMed1997

Penetrating left thoracoabdominal trauma: the incidence and clinical presentation of diaphragm injuries.

OBJECTIVE: The objective of this study was to (1) determine the incidence of diaphragmatic injuries in penetrating left thoracoabdominal trauma and (2) evaluate the role of laparoscopy in detecting clinically occult diaphragmatic injuries. PATIENTS AND METHODS: One hundred nineteen consecutive patients with penetrating injuries to the left thoracoabdominal region presenting to Los Angeles County-University of Southern California Medical Center were prospectively evaluated during an 8-month period. Either celiotomy (with hemodynamic instability or peritonitis) or laparoscopy was performed. Results of the clinical examination and roentgenographic findings were recorded preoperatively. RESULTS: One hundred seven patients were fully evaluated. Fifty patients required emergent celiotomy. Fifty-seven patients underwent laparoscopy. The overall incidence of diaphragmatic injuries was 42% (59% for gunshot wounds, 32% for stab wounds). Among the 45 patients with diaphragmatic injuries, 31% had no abdominal tenderness, 40% had a normal chest roentgenogram, and 49% had an associated hemopneumothorax. Fifteen of the patients undergoing laparoscopy (26%) had occult diaphragm injuries. CONCLUSION: (1) The incidence of diaphragmatic injuries in association with penetrating left thoracoabdominal trauma is high. (2) The clinical and roentgenographic findings are unreliable at detecting occult diaphragmatic injuries. (3) Laparoscopy is a vital tool for detecting occult diaphragmatic injuries among patients who have no other indications for formal celiotomy.

Abdominal Injuries↗
PubMed1997

Aminoglycoside levels in critically ill surgical patients: the implications of physiologic criteria of sepsis.

We retrospectively reviewed medical records and computerized critical care data for 40 consecutive critically ill surgical patients receiving "standard" doses (1.5 to 2.0 mg/kg loading dose and 3 to 5 mg/kg/day) of gentamicin or tobramycin for gram-negative infections. End points measured were serum drug levels and clearance of infection. Therapeutic serum aminoglycoside levels were achieved within 48 hours of therapy by only 7 patients (17.5%). Among the remaining 33 patients, significantly fewer septic than nonseptic patients had clearance of their infection (11% vs 92%). Specific physiologic criteria of sepsis may be used to identify critically ill patients who will most likely benefit from aggressive initial aminoglycoside dosing when these drugs are used to treat gram-negative infections.

APACHE↗
PubMed1997

Factors predicting prolonged mechanical ventilation in critically injured patients: introducing a simplified quantitative risk score.

Our objective was to identify a set of readily available and easily obtainable parameters that would predict prolonged mechanical ventilation in the critically injured patient. A surgical intensive care unit of an academic Level I trauma center. Prospectively collected data were retrospectively analyzed on all critically injured patients receiving mechanical ventilation for more than 2 days between January and December 1994. Prolonged mechanical ventilation (PMV) was defined as the need for mechanical ventilatory support for more than 7 days. One hundred and nineteen patients entered the final analysis. Of these, 63 remained on the ventilator for 7 days or less and 56 for more than 7 days. The Injury Severity Score (ISS), partial arterial oxygen tension (PaO2)/inspired fraction of oxygen (FiO2), net fluid balance, and use of Swan-Ganz were significantly different between the two groups when calculated 48 hours after surgical intensive care unit admission. Furthermore, we dichotomized these four variables across cutpoints that were determined by statistical analysis (ISS more or less than 20, PaO2/FiO2 more or less than 250, fluid retention more or less than 2000 cc, and presence or absence of Swan-Ganz). Again, significantly more patients required PMV if they had any one of the following: Swan-Ganz, ISS more than 20, PaO2/FiO2 less than 250, or fluid retention more than 2000 cc at 48 hours. An easily calculated five-point risk score (0-4 points) for predicting PMV based on these four variables was developed. Among the 35 patients at the extremes of the risk score (0 or 4 points), 33 (94.3%) were correctly prognosticated as to their needs for PMV. The need for an easily calculated score, which is derived from readily available parameters and can reliably identify patients with prolonged needs for ventilatory support, is obvious in the trauma setting. We describe a five-point risk score by which we can predict the need for PMV early in the course of the disease. Resource utilization and personnel allocation issues, as well as important therapeutic procedures, can be planned based on this score.

Adolescent↗
PubMed1996

Paramedic vs private transportation of trauma patients. Effect on outcome.

BACKGROUND: Prehospital emergency medical services (EMS) play a major role in any trauma system. However, there is very little information regarding the role of prehospital emergency care in trauma. To investigate this issue, we compared the outcome of severely injured patients transported by paramedics (EMS group) with the outcome of those transported by friends, relatives, bystanders, or police (non-EMS group). DESIGN: We compared 4856 EMS patients with 926 non-EMS patients. General linear model analysis was performed to test the hypothesis that hospital mortality is the same in EMS and non-EMS cases, controlling for the following confounding factors, which are not affected by mode of transportation: age, gender, mechanism of injury, cause of injury, Injury Severity Score (ISS), and severe head injury. Crude, specific, and adjusted mortality rates and relative risks were also derived for the EMS and non-EMS groups. SETTING: Large, urban, academic level I trauma center. PATIENTS: All patients meeting the criteria for major trauma. RESULTS: The two groups were similar with regard to mechanism of injury and the need for surgery or intensive care unit admission. The crude mortality rate was 9.3% in the EMS group and 4.0% in the non-EMS group (relative risk, 2.32; P < .001). After adjustment for ISS, the relative risk was 1.60 (P = .002). Subgroup analysis showed that among patients with ISS greater than 15, those in the EMS group had a mortality rate twice that of those in the non-EMS group (28.8% vs 14.1%). After controlling for confounding factors, the adjusted mortality among patients with ISS greater than 15 was 28.2% for the EMS group and 17.9% for the non-EMS group (P < .001). CONCLUSIONS: Patients with severe trauma transported by private means in this setting have better survival than those transported via the EMS system. Large prospective studies are needed to identify the factors responsible for this difference.

Adult↗
PubMed1996

Noninvasive physiologic monitoring of high-risk surgical patients.

OBJECTIVES: To study the feasibility of multicomponent noninvasive monitoring, consisting of a new bioimpedance method for estimating cardiac output together with routine pulse oximetry and transcutaneous oximetry, and to compare physiologic data obtained noninvasively with hemodynamic and oxygen transport data obtained by standard invasive pulmonary artery thermodilution catheter to evaluate circulatory function in high-risk surgical patients. DESIGN: Prospective descriptive analysis of the time course of physiologic patterns in surgical patients. SETTING: University-run county hospital. PATIENTS: Seventy-one consecutively monitored, high-risk critically ill surgical patients in their perioperative period. OUTCOME MEASURES: Simultaneous measurements by invasive and noninvasive methods to describe and compare the temporal physiologic patterns of survivors and nonsurvivors. RESULTS: The new impedance cardiac output estimations closely approximated those of the thermodilution method (r = 0.82, P < .001). Episodes of hypotension, tachycardia, low cardiac index, arterial hemoglobin desaturation, low transcutaneous oximetry, reduced oxygen delivery, and low oxygen consumption occurred with both groups but were more pronounced in the nonsurvivors than in the survivors. Noninvasive monitoring provided information similar to that of the thermodilution method. Both approaches indicated low flow and poor tissue perfusion (oxygenation) that was worse in the nonsurvivors. CONCLUSIONS: The multicomponent noninvasive monitoring provides continuous online, real-time displays of physiologic data that allow immediate recognition of circulatory dysfunction as well as the means to titrate therapy to appropriate predetermined therapeutic goals. The noninvasive systems are easy to apply, safe, inexpensive, reasonably accurate, and cost-effective.

Adult↗
PubMed1996

Transmediastinal gunshot wounds. A reconsideration of the role of aortography.

OBJECTIVE: To evaluate the contribution of aortography in the management of stable patients with transmediastinal gunshot wounds. DESIGN: Retrospective review of clinical records. SETTING: Level I urban trauma center. PATIENTS: Forty-three patients with aortic or esophageal gunshot injuries. INTERVENTIONS: Patients who were stable after initial resuscitation underwent aortography followed by esophagography. MAIN OUTCOME MEASURES: Hemodynamic status on admission, time devoted to diagnostic workup, surgical (or autopsy) findings, morbidity, and mortality. RESULTS: There were 24 esophageal injuries and 20 aortic injuries. Patients with aortic injuries were less often stable for aortography (10% vs 42%; P = .02), and fewer of them survived (15% vs 58%; P = .01). In no patient was the aortic injury initially detected by aortography. Stable patients with esophageal injuries experienced an average 11-hour interval between injury and surgery (nearly 3 hours attributable to aortography). CONCLUSION: Esophageal evaluation should precede aortography in the workup of stable patients with transmediastinal gunshot wounds.

Adolescent↗
PubMed1996

Management options in vertebral artery injuries.

The treatment of 22 patients with vertebral artery injuries was reviewed. Only four patients required an emergency operation. Most of the injuries (13 of 22) were successfully managed by observation. Five patients were managed by angiographic embolization which was successful in three. In three patients with an aneurysm and arteriovenous fistula, proximal embolization of the vascular lesion was not adequate and a suboccipital craniectomy was required for distal ligation. Most vertebral artery injuries can safely be managed without an operation, or by angiographic embolization. Surgical intervention should be reserved for patients with severe bleeding or where embolization has failed.

Adolescent↗
PubMed1996

Laparoscopic evaluation of penetrating thoracoabdominal traumatic injuries.

BACKGROUND: General surgeons' recent familiarity with advanced laparoscopic techniques have rendered laparoscopy feasible safely in the trauma setting. Traditionally high rates of nontherapeutic laparotomies also contribute to this increased interest. This study was undertaken to determine the predictive value and accuracy of diagnostic laparoscopy (DL) in evaluation of penetrating thoracoabdominal trauma. METHODS: Entry criteria included thoracoabdominal gunshot (GSW) or stab wounds (SW) in otherwise hemodynamically stable patients. A high index of suspicion for either hemoperitoneum, peritonitis, or diaphragmatic injury was required for inclusion. All patients underwent DL in the operating room followed by standard laparotomy. The findings of the two evaluations were compared. RESULTS: Twenty-four patients were included in the study. Twenty males and 4 females with an average age of 34 years made up the group. Violation of the peritoneal cavity was present in 21 cases and absent in 3. No intraabdominal injuries were found during laparotomy in the latter three cases without peritoneal violation. The specificity and positive predictive value were 100% for lesions of the diaphragm, liver, spleen, pancreas, kidney, and hollow viscus. The sensitivity was highest for liver and spleen injuries (88%), followed by diaphragmatic injuries (83%), pancreas and kidney injuries (50%), and lowest for injuries of hollow viscus (25%). The negative predictive value was 95, 99, 91, and 57%, respectively, for these organs. CONCLUSIONS: DL could have avoided unnecessary laparotomy in 38% of cases in this study. There were no complications related to laparoscopy. The greatest value of DL in penetrating thoracoabdominal injuries is in the evaluation of peritoneal violation, diaphragmatic, and upper abdominal solid-organ injuries. It is not ideal for predicting hollow viscus injuries.

Abdominal Injuries↗