Search PubMed⌕ Search

Biomedical subjects

C W Schwab

Publications and source records attributed to C W Schwab.

At least 19 recordsLinked to original sources

Computed tomography in the evaluation of penetrating neck trauma: a preliminary study.

HYPOTHESIS: Penetrating neck trauma has traditionally been evaluated by surgical exploration and/or invasive diagnostic studies. We hypothesized that computed tomography (CT), used as an early diagnostic tool to accurately determine trajectory, would direct or eliminate further studies or procedures in stable patients with penetrating neck trauma. DESIGN: Retrospective case series. SETTING: Academic, urban, level I trauma center. PATIENTS: Hemodynamically stable patients without hard signs of vascular injury or aerodigestive violation who had sustained penetrating trauma to the neck. INTERVENTIONS: Patients underwent a spiral CT as an initial diagnostic study after initial evaluation in the trauma bay. Further invasive studies were directed by CT findings. MAIN OUTCOME MEASURES: Number of invasive studies performed. RESULTS: Twenty-three patients were identified during the 30-month period. Nineteen patients sustained gunshot wounds; 3, shotgun wounds; and 1, a stab wound. One patient died of a cranial gunshot wound. Three isolated zone I, 1 isolated zone II, 9 isolated zone III, and 10 multiple neck zone trajectories were evaluated. Thirteen patients were identified by CT to have trajectories remote from vital structures and required no further evaluation. Ten patients underwent angiography. Only 2 underwent bronchoscopy and esophagoscopy. Four patients were discharged from the emergency department; 7 other patients were discharged within 24 hours. No adverse patient events occurred before, during, or after CT scan. CONCLUSIONS: Computed tomography in stable selected patients with penetrating neck trauma appears safe. Invasive studies can often be eliminated from the diagnostic algorithm when CT demonstrates trajectories remote from vital structures. As a result, efficient evaluation and early discharge from the trauma bay or emergency department can be realized. Further prospective study of CT scan after penetrating neck trauma is needed.

Adult↗

The role of nephrectomy in the acutely injured.

HYPOTHESIS: The high mortality in patients who undergo nephrectomy after trauma is not secondary to the nephrectomy itself but is the consequence of a more severe constellation of injuries associated with renal injuries that require operative intervention. DESIGN: A retrospective review of all patients identified using International Classification of Diseases, Ninth Revision codes as having sustained renal injuries over a 62-month period. PATIENTS: Seventy-eight patients with renal injuries who underwent exploratory laparotomy were identified. METHODS: All medical records were reviewed for patient management, definitive care, and outcome. Based on outcome, patients were assigned to either the survivor or nonsurvivor group. For patients who underwent nephrectomy, intraoperative core temperature changes, estimated blood loss, and operative time were also reviewed. RESULTS: Seventy-eight patients with renal injuries who underwent exploratory laparotomy were identified. Twenty-nine patients underwent laparotomy with conservative management of the renal injury, of whom 5 (17.2%) died. Twelve patients had renal injuries repaired and all survived. Thirty-seven patients underwent nephrectomy, of whom 16 (43.2%) died. Compared with nephrectomy survivors, nephrectomy nonsurvivors had a significantly lower initial systolic blood pressure, higher Injury Severity Score, higher incidence of extra-abdominal injuries, shorter operative duration, and higher estimated operative blood loss. The nephrectomy survivors' core temperature increased a mean of 0.5 degrees C in the operating room, while the nephrectomy nonsurvivors' core temperature cooled a mean of 0.8 degrees C. CONCLUSIONS: Patients who undergo trauma nephrectomy tend to be severely injured and hemodynamically unstable and warrant nephrectomy as part of the damage control paradigm. That a high percentage of patients die after nephrectomy for trauma demonstrates the severity of the overall constellation of injury and is not a consequence of the nephrectomy itself.

Acute Disease↗

Selection of nonoperative management candidates.

The liver and spleen are the most commonly injured intraabdominal organs and comprise most of the injuries to the solid viscera during blunt abdominal injury. The contrast-enhanced computed tomography (CT) scan has emerged as an accurate, safe diagnostic tool for blunt torso trauma, making nonoperative management of even severe injury to the liver and spleen possible. This review concentrates on the trends, patient selection criteria, and some of the risks of nonoperative management of hemodynamically stable patients with blunt liver and spleen injury.

Humans↗

Penetrating esophageal injuries: multicenter study of the American Association for the Surgery of Trauma.

OBJECTIVE: The purpose of this study was to define the period of time after which delays in management incurred by investigations cause increased morbidity and mortality. The outcome study is intended to correlate time with death from esophageal causes, overall complications, esophageal related complications, and surgical intensive care unit length of stay. METHODS: This was a retrospective multicenter study involving 34 trauma centers in the United States, under the auspices of the American Association for the Surgery of Trauma Multi-institutional Trials Committee over a span of 10.5 years. Patients surviving to reach the operating room (OR) were divided into two groups: those that underwent diagnostic studies to identify their injuries (preoperative evaluation group) and those that went immediately to the OR (no preoperative evaluation group). Statistical methods included Fisher's exact test, Student's T test, and logistic regression analysis. RESULTS: The study involved 405 patients: 355 male patients (86.5%) and 50 female patients (13.5%). The mean Revised Trauma Score was 6.3, the mean Injury Severity Score was 28, and the mean time interval to the OR was 6.5 hours. There were associated injuries in 356 patients (88%), and an overall complication rate of 53.5%. Overall mortality was 78 of 405 (19%). Three hundred forty-six patients survived to reach the OR: 171 in the preoperative evaluation group and 175 in the no preoperative evaluation group. No statistically significant differences were noted in the two groups in the following parameters: number of patients, age, Injury Severity Score, admission blood pressure, anatomic location of injury (cervical or thoracic), surgical management (primary repair, resection and anastomosis, resection and diversion, flaps), number of associated injuries, and mortality. Average length of time to the OR was 13 hours in the preoperative evaluation group versus 1 hour in the no preoperative evaluation group (p < 0.001). Overall complications occurred in 134 in the preoperative evaluation group versus 87 in the no preoperative evaluation group (p < 0.001), and 74 (41%) esophageal related complications occurred in the preoperative evaluation group versus 32 (19%) in the no preoperative evaluation group (p = 0.003). Mean surgical intensive care unit length of stay was 11 days in the preoperative evaluation group versus 7 days in the no preoperative evaluation group (p = 0.012). Logistic regression analysis identified as independent risk factors for the development of esophageal related complications included time delays in preoperative evaluation (odds ratio, 3.13), American Association for the Surgery of Trauma Organ Injury Scale grade >2 (odds ratio, 2.62), and resection and diversion (odds ratio, 4.47). CONCLUSION: Esophageal injuries carry a high morbidity and mortality. Increased esophageal related morbidity occurs 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, rapid diagnosis and definitive repair should be made a high priority.

Adolescent↗

Penetrating colon injuries requiring resection: diversion or primary anastomosis? An AAST prospective multicenter study.

BACKGROUND: The management of colon injuries that require resection is an unresolved issue because the existing practices are derived mainly from class III evidence. Because of the inability of any single trauma center to accumulate enough cases for meaningful statistical analysis, a multicenter prospective study was performed to compare primary anastomosis with diversion and identify the risk factors for colon-related abdominal complications. METHODS: This was a prospective study from 19 trauma centers and included patients with colon resection because of penetrating trauma, who survived at least 72 hours. Multivariate logistic regression analysis was used to compare outcomes in patients with primary anastomosis or diversion and identify independent risk factors for the development of abdominal complications. RESULTS: Two hundred ninety-seven patients fulfilled the criteria for inclusion and analysis. Overall, 197 patients (66.3%) were managed by primary anastomosis and 100 (33.7%) by diversion. The overall colon-related mortality was 1.3% (four deaths in the diversion group, no deaths in the primary anastomosis group, p = 0.012). Colon-related abdominal complications occurred in 24% of all patients (primary repair, 22%; diversion, 27%; p = 0.373). Multivariate analysis including all potential risk factors with p values < 0.2 identified three independent risk factors for abdominal complications: severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis. The type of colon management was not found to be a risk factor. Comparison of primary anastomosis with diversion using multivariate analysis adjusting for the above three identified risk factors or the risk factors previously described in the literature (shock at admission, delay > 6 hours to operating room, penetrating abdominal trauma index > 25, severe fecal contamination, and transfusion of > 6 units blood) showed no statistically significant difference in outcome. Similarly, multivariate analysis and comparison of the two methods of colon management in high-risk patients showed no difference in outcome. CONCLUSION: The surgical method of colon management after resection for penetrating trauma does not affect the incidence of abdominal complications, irrespective of associated risk factors. Severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis are independent risk factors for abdominal complications. In view of these findings, the reduced quality of life, and the need for a subsequent operation in colostomy patients, primary anastomosis should be considered in all such patients.

Adult↗

Anaphylactic shock from a latex allergy in a patient with spinal trauma.

Allergy to latex is a condition that affects patients as well as health care workers. It is a spectrum of immunologic disorders that ranges from mild hypersensitivity to life-threatening anaphylaxis. Beginning in the early 1970s, the health care community has become more aware of this entity, leading to many improvements in the understanding, diagnosis and treatment of patients with latex allergy. Many hospitals have developed protocols and procedures for patients with latex sensitivity. However, some physicians remain unaware of the logistics of taking care of patients with this disorder. We present a case of a severe anaphylactic reaction to latex in a trauma patient with a spinal cord injury. The difficulty of treating the acutely injured patient with this disorder is illustrated. A list of equipment that may be included in a latex-free emergency kit is provided.

Adult↗

Evolution in damage control for exsanguinating penetrating abdominal injury.

OBJECTIVE: Damage control (DC) has proven valuable in exsanguinated patients. The purpose of this study was to quantify and qualify the impact of current damage control principles applied in a penetrating abdominal injury (PAI) population. METHODS: Over a 3-year period (June 1997-May 2000), of 271 laparotomies for PAI, 24 patients underwent DC (8.9%). Demographics, injury grade, resuscitative and operative parameters, acid-base status, coagulation profiles, fluid/transfusion requirements, definitive repairs, abdominal closure, complications, and outcomes were reviewed. Data were compared with our DC experience a decade earlier. Fisher's exact test was used for comparisons. RESULTS: Overall survival improved for equivalent Injury Severity Score, Revised Trauma Score, TRISS, admission systolic blood pressure, operating room systolic blood pressure, and Penetrating Abdominal Trauma Index score. Solids (1.2 vs. 1.3), hollow organ (1.5 vs. 1.7), and major vascular injuries (0.5 vs. 0.8) per patient remain unchanged. Currently, there was less hypothermia with equivalent operating room times. In intensive care unit survivors, acid-base status was similar but coagulopathy and hypothermia were less severe. Definitive colon management has shifted from ostomies to anastomoses. Eventual fascial closure occurred in 14 of 19 (74%) compared with 12 of 14 (86%) in the historical group. There were three gastrointestinal fistulae (one pancreatic), one anastomotic leak, and three intra-abdominal abscesses. CONCLUSION: Continued application of DC principles has led to improved survival with PAI. Better control of temperature, experience with the open abdomen, and intensive care unit care may be causative.

Abdominal Injuries↗

Defining the learning curve for the Focused Abdominal Sonogram for Trauma (FAST) examination: implications for credentialing.

Focused Abdominal Sonogram for Trauma (FAST) examination is being used increasingly for the torso evaluation of injured patients. In a controlled setting using peritoneal dialysis patients as models for injured patients with free fluid we hypothesized that more experienced providers would perform FAST with greater accuracy. Twelve fellow or attending level trauma surgeons, two radiologists, and one ultrasound technician were studied for their ability to detect intraperitoneal fluid (0-1600 cm3) in nine peritoneal dialysis patients with two different volumes of dialysate/patient. FAST experience with injured patients was defined as minimal (<30 patients examinations), moderate (30-100), or extensive (>100). All surgeons had participated in a didactic/practical course before the study. Test results were reported as "+" or "-" by the participant; "+" results were further quantified by volume. The sensitivity of those in the minimal-, moderate-, and extensive-experience to detect <1 L was 45, 87, and 100 per cent, respectively; the accuracy in detecting dialysate volume within 250 cm3 was 38, 63, and 90 per cent, respectively. In this controlled setting the accuracy of FAST particularly in diagnosing smaller volumes, as well as the ability to quantify volume, improves with experience. The learning curve for FAST starts to flatten out at 30 to 100 examinations. Training and credentialing policies should consider these findings to optimize patient care.

Abdominal Injuries↗

Nonoperative management of solid abdominal organ injuries from blunt trauma: impact of neurologic impairment.

The role of nonoperative management of solid abdominal organ injury from blunt trauma in neurologically impaired patients has been questioned. A statewide trauma registry was reviewed from January 1993 through December 1995 for all adult (age >12 years) patients with blunt trauma and an abdominal solid organ injury (kidney, liver, or spleen) of Abbreviated Injury Scale score > or =2. Patients with initial hypotension (systolic blood pressure <90 mm Hg) were excluded. Patients were stratified by Glasgow Coma Score (GCS) into normal (GCS 15), mild to moderate (GCS 8-14), and severe (GCS < or =7) impairment groups. Management was either operative or nonoperative; failure of nonoperative management was defined as requiring laparotomy for intraabdominal injury more than 24 hours after admission. In the 3-year period 2327 patients sustained solid viscus injuries; 1561 of these patients were managed nonoperatively (66 per cent). The nonoperative approach was initiated less frequently in those patients with greater impairment in mental status: GCS 15, 71 per cent; GCS 8 to 14, 62 per cent; and GCS < or =7, 50 per cent. Mortality, hospital length of stay, and intensive care unit days were greater in operatively managed GCS 15 and 8 to 14 groups but were not different on the basis of management in the GCS < or =7 group. Failure of nonoperative management occurred in 94 patients (6%). There was no difference in the nonoperative failure rate between patients with normal mental status and those with mild to moderate or severe head injuries. Nonoperative management of neurologically impaired hemodynamically stable patients with blunt injuries of liver, spleen, or kidney is commonly practiced and is successful in more than 90 per cent of cases. No differences were noted in the rates of delayed laparotomy or survival between normal, mild to moderately head-injured, and severely head-injured patients.

Abdominal Injuries↗

Preoperative radiographic staging for ureteral injuries is not warranted in patients undergoing celiotomy for trauma.

Preoperative radiographic staging of the urinary tract has been shown to be inaccurate with regard to the ureter. The purpose of this study was to assess the need for radiographic staging of the injured patient for the diagnosis of ureteral injury before operative exploration. We conducted a retrospective review of all patients who sustained injury of the ureter as the result of external trauma over an 8 Y2-year period at an urban and suburban Level I trauma center. All patients were injured through penetrating mechanisms and underwent laparotomy. Only three patients had preoperative radiographic staging of the urinary tract. No ureteral injuries were missed. We conclude that surgical exploration of the ureter is sufficiently accurate to obviate the need for preoperative radiographic staging of the ureters in patients who have sustained penetrating injury and warrant laparotomy.

Adolescent↗

The traveling intensive care unit patient. Road trips.

Transport of critically ill or injured patients in the hospital is a necessary part of ICU care. Although the overall severity of misadventures occurring during patient transfer is minimal, potential complications risk patient deterioration in settings that may not be equipped to handle cardiovascular, respiratory, or neurologic emergencies safely. The critical care team should provide the same level of monitoring and care to the transported patient outside the ICU as he or she receives the unit. Each hospital should have a system that meets acceptable standards for safe transfer of the ICU patient, which minimizes risk and maximizes diagnostic and treatment yield.

Critical Care↗

Assessing the need for reintubation: a prospective evaluation of unplanned endotracheal extubation.

OBJECTIVE: Unplanned endotracheal extubation (UEE) is a common complication in medical intensive care units but very little data about UEE in surgical populations are available. Our hypothesis is that the surgical intensive care unit (SICU) population requires reintubation less frequently compared with the medical intensive care unit population. We prospectively gathered data on patients in a SICU in an attempt to identify the incidence of UEE and to study the need for reintubation after UEE. METHODS: During an 18-month period, we prospectively identified SICU patients from a quality improvement database who required ventilatory support. All patients who self-extubated were included in the study. RESULTS: Fifty-eight of 1,178 intubated patients experienced unplanned extubation 61 times during the 18-month period. A total of 22 patients (36%) required reintubation, whereas 39 patients (64%) did not. Thirty-three patients self-extubated while being actively weaned from ventilatory support. Of these, only 5 patients (15%) required reintubation and 28 patients (85%) did not (p < 0.01). CONCLUSION: A total of 85% of patients who self-extubate during the weaning process did not require reintubation in our study. Those who have an FiO2 >50%, a lower PaO2/FiO2 ratio, had UEE occur by accident, or were not being weaned when UEE occurred required reintubation more frequently. These data suggest that some of our SICU patients are intubated longer than necessary, which may translate into more ventilator related complications, longer ICU stays and increased cost.

Adult↗

Improving the approach to organ donation: a review.

Organ transplantation continues to be hindered by a limited supply of organs. A significant percentage of potential organ donors are lost to either medical failure or inability to obtain consent for donation. In a surgical intensive care unit (ICU) we have refocused our efforts toward aggressive resuscitation, directed by control of coagulopathy, invasive monitoring, and dedicated ICU management while implementing a rapid brain death determination protocol. Over a 6-year period the length of stay until the legal determination of brain death is made has been significantly shortened (12.0 vs. 3.4 hours; p < 0.05), as have associated charges despite this more aggressive approach. As a result, we have eliminated medical failures prior to donation (13% vs. 0%) and increased consent rates (44% vs. 71%; p < 0.05). These efforts have significantly improved the number of organs harvested per eligible donor (1.8 vs. 3.4; p < 0.05). In addition, the number of organs per actual donor has increased and is now markedly greater than the U.S. national average (4.7 vs. 3.7). We believe the approach presented, if widely applied, could potentially improve the current organ supply shortage.

Blood Coagulation Disorders↗

Hypomagnesemia in trauma patients.

The objective of this study was to determine the incidence of hypomagnesemia in injured patients (versus a general hospital cohort) and to compare total and ionized values with each other and with the incidence of injury severity and ethanol level. It was a descriptive study of consecutive injured patients at a level II trauma center. For 3 months subjects underwent admission paired analysis of blood total magnesium (TMg) and ionized magnesium (IMg). IMg was determined by microanalysis of whole blood (Nova Biomedical, NovaSP9). During the same time period, all hospital samples for TMg (m = 1308) underwent simultaneous IMg testing. Pearson correlation coefficients were determined for IMg versus TMg, Injury Severity Score (ISS), Trauma Score (TS), Glasgow Coma Scale (GCS), and blood units transfused. By convention, hypomagnesemia was defined as TMg < or =1.6 mg/dl and IMg < or = 0.5 mg/dl. Altogether 43% of 113 trauma patients had low magnesium levels compared to 30% of noninjured cohorts (p<0.05). The correlation coefficient (r(2)) for TMg and IMg was 0.74 for TMg values >1.6, but for TMg < or =1.6 the r(2) was 0.35. Coefficients for IMg and ISS, TS, GCS, units transfused, and ethanol level were 0.06, 0.08, 0.10, 0.04, and 0.01, respectively. Mean IMg was 0.57+/-0.09 mg/dl with ethanol ingestion and 0.56+/-0.06 mg/dl without ethanol ingestion (mean +/- SD, p>0.05). It was concluded that hypomagnesia is common in injured patients but does not correlate with indices of injury severity or ethanol level. TMg is not a good predictor of IMg at low levels. Trauma patients may benefit from determination of IMg for accurate diagnosis of a low Mg level to facilitate repletion.

Adult↗