Digital hand-held sonography utilised for the focused assessment with sonography for trauma: a pilot study

OBJECTIVE

To evaluate the accuracy of the focused assessment with sonography for trauma (FAST) exam performed with a digital hand-held ultrasound machine in the emergency evaluation and resuscitation of trauma victims.

INTRODUCTION

The FAST exam is a valuable screening tool in the evaluation of abdominal trauma. New digital ultrasound units have recently become available which can be hand-carried by clinicians responding to the earliest phases of trauma care.

MATERIALS AND METHODS

Forty-seven victims of blunt trauma and 3 victims of penetrating trauma underwent FAST examinations performed by an attending trauma surgeon. Scans were performed with a Sonosite 180, 2.4-kg machine utilising a 5-2 MHz curved array transducer. The results of the hand-held FAST were compared with formal sonographic examinations performed by radiology department personnel, computed tomographic (CT) studies, operative findings and ultimate hospital course.

RESULTS

In victims of blunt trauma, 7 of 8 true fluid collections were detected, and 38 out of 39 cases without the presence of fluid were correctly excluded. There was 1 false positive and 1 false negative determination, resulting in a sensitivity of 86%, specificity of 97%, positive predictive value of 88%, and a negative predictive value of 97%. The overall accuracy was 96% for victims of blunt trauma. The technique expediently detected intra-peritoneal bleeding in 2 victims of lateral penetrating abdominal trauma. Utilised as the initial component of a diagnostic protocol, no inappropriate management strategies were suggested.

CONCLUSIONS

Digital hand-held sonography by clinicians can accurately allow the early performance of FAST exams. This exam may accurately and safely extend the physical senses of the examining physician.

Major intrahepatic bile duct injuries detected after laparotomy: selective nonoperative management

BACKGROUND

Abdominal trauma causing major intrahepatic bile duct injury is a relatively uncommon occurrence. Most authorities recommend operative, usually resectional, management of these injuries when recognized, citing increased risks of complications and mortality with nonoperative management. However, very few data have been published to document the optimal management of these challenging injuries.

METHODS

We present a series of five patients with significant hepatic injury and documented major bile duct injury managed at a single provincial trauma center. All of these patients had first- or second-order bile duct injuries diagnosed using endoscopic retrograde cholangiopancreatography and had developed complications caused by the ductal injury.

RESULTS

In all patients, the bile duct injury and resulting complication were successfully managed by a combination of endoscopic drainage procedures and interventional radiology techniques. Average length of hospital stay for these patients was 45 days. All patients eventually attained preinjury functional status.

CONCLUSION

Nonoperative techniques can be used to successfully manage selected patients and represent a reasonable alternative to operative intervention and resectional therapy, especially in the compromised patient. Extended length of stay is to be expected, but good outcomes can be achieved.

Hypothermia and the trauma patient

Hypothermia has profound effects on every system in the body, causing an overall slowing of enzymatic reactions and reduced metabolic requirements. Hypothermic, acutely injured patients with multisystem trauma have adverse outcomes when compared with normothermic control patients. Trauma patients are inherently predisposed to hypothermia from a variety of intrinsic and iatrogenic causes. Coagulation and cardiac sequelae are the most pertinent physiological concerns. Hypothermia and coagulopathy often mandate a simplified approach to complex surgical problems. A modification of traditional classification systems of hypothermia, applicable to trauma patients is suggested. There are few controlled investigations, but clinical opinion strongly supports the active prevention of hypothermia in the acutely traumatized patient. Preventive measures are simple and inexpensive, but the active reversal of hypothermia in much more complicated, often invasive and controversial. The ideal method of rewarming is unclear but must be individualized to the patient and institution specific. An algorithm reflecting newer approaches to traumatic injury and technical advances in equipment and techniques is suggested. Conversely, hypothermia has selected clinical benefits when appropriately used in cases of trauma. Severe hypothermia has allowed remarkable survivals in the course of accidental circulatory arrest. The selective application of mild hypothermia in severe traumatic brain injury is an area with promise. Deliberate circulatory arrest with hypothermic cerebral protection has also been used for seemingly unrepairable injuries and is the focus of ongoing research.

Trauma in pregnancy: maternal and fetal outcomes

OBJECTIVE

Pregnancy imposes significant physiologic demands that may confuse and complicate the evaluation, resuscitation, and definitive management of pregnant women who sustain trauma. Accurate prediction of fetal outcome after trauma remains elusive. The objective of this study was to characterize patterns of injury in pregnant women, to determine if pregnancy affects maternal morbidity and mortality after trauma, and to identify predictors of fetal death.

METHODS

We performed a retrospective, case-control analysis of all injured pregnant patients admitted to the Trauma Service at the University of California San Diego Medical Center from 1985 to 1995.

RESULTS

We identified 114 injured pregnant patients. Motor vehicle crashes accounted for 70% of injuries, and of these, 46% of patients were not using seat belts or helmets. Violence accounted for 12% of injuries. Injured pregnant women with Injury Severity Scores > 8 demonstrated similar mortality, morbidity, and length of stay to matched nonpregnant control patients. Pregnant women were more likely to sustain serious abdominal injury and were less likely to sustain severe head injury. Identified risk factors for fetal loss include maternal death, overall maternal injury severity, the presence of severe abdominal injury, and the presence of hemorrhagic shock.

CONCLUSION

There appears to be a group of pregnant women in San Diego at high risk for traumatic injury who should be targeted for preventative strategies including improved seat belt use. Pregnancy does not increase mortality or morbidity after trauma but influences the pattern of injury. Maternal death, high Injury Severity Score, serious abdominal injury, and hemorrhagic shock are risk factors for fetal loss.

Lethal injuries and time to death in a level I trauma center

BACKGROUND

The purpose of this study was to identify the causes and time to death of all trauma victims who died at a level I trauma center during an 11-year period.

STUDY DESIGN

Autopsies were performed on all patients who died secondary to trauma. Retrospective review of these autopsies was carried out and appended to existing trauma registry data. Standard definitions were used to attribute the cause of death in each case. Preventable deaths were determined by a standardized peer review process.

RESULTS

Between January 1985 and December 1995, a total of 900 trauma patients died. This represented 7.3% of all major trauma admissions (12,320). Seventy percent of these patients died within the first 24 hours of admission. Thoracic vascular and central nervous system (CNS) injuries were the most common causes of death in the first hour after admission to the hospital. CNS injuries were the most common causes of death within the 72 deaths after admission. Acute inflammatory processes (multiple organ failure, acute respiratory distress syndrome, and pneumonia) and pulmonary emboli were the leading causes of death after the first 72 hours. Overall, 43.6% (393 of 900) of all trauma deaths were caused by CNS injuries, making this the most common cause of death in our study. The preventable death rate was 1%.

CONCLUSIONS

The first 24 hours after trauma are the deadliest for these patients. Primary and secondary CNS injuries are the leading causes of death. Prevention, early identification, and treatment of potentially lethal injuries should remain the focus of those who treat trauma patients.

Is operating room resuscitation a way to save time?

BACKGROUND

Direct admission to the operating room (OR) can shorten the time to incision. A protocol for operating room resuscitation was established with patient triage based on (1) cardiac arrest, (2) hypotension unresponsive to field fluid resuscitation, or (3) uncontrolled external hemorrhage.

METHODS

Operating room resuscitation over 11 years was reviewed to determine whether the triage criteria correctly identified patients requiring operation. Survival was analyzed and compared with the probability of survival (Ps) determined at the scene.

RESULTS

Operating room resuscitation patients were more likely to require a major operation regardless of mechanism of injury. Of 476 patients with penetrating injury, 170 patients had persistent low blood pressure (<90 mm Hg), and 146 (85.9%) of these required major operative intervention. The mean time to incision in this group was 21.7-67.5 minutes less than for patients not receiving OR resuscitation. Observed survival was significantly greater than that predicted for this group.

CONCLUSIONS

Field triage criteria are able to reliably identify patients who require immediate major operative intervention. Direct admission to the OR results in a more timely initiation of operative therapy for patients requiring emergency surgical procedures.

Elevated selectin levels after severe trauma: a marker for sepsis and organ failure and a potential target for immunomodulatory therapy

Severe injury is frequently complicated by sepsis and organ failure. Activated neutrophils adherent to inflamed endothelia have been implicated in the pathogenesis of these complications. Identification of high-risk patients to target immunomodulatory therapy, however, remains an elusive goal. We postulated that (1) patients at risk for sepsis and organ failure could be identified by measuring shed selectin adhesions molecules as a marker of endothelial activation after injury and reperfusion, and (2) these elevated selectin levels would correlate with injury severity, shock, major complications, and mortality.

METHODS

Blood samples were drawn from 50 patients with multiple trauma every 2 hours after admission for the first 24 hours, and every 6 hours for the subsequent 24 hours, and assayed for levels of shed E- and P-selectin. Patients were then stratified according to Injury Severity Score (ISS), presence or absence of shock, presence or absence of organ failure and/or infectious complications, and finally, death versus survival.

RESULTS

Trauma patients who had ISS < 30, who did not develop shock, sepsis, or organ dysfunction, had minimal increase in circulating E- and P-selectin over admission levels. In patients who subsequently developed infectious complications, organ dysfunction, or both, or subsequently went on to die, elevated levels of E-selectin levels were evident by 36 hours, and in some cases, earlier. Differences between nonsurvivors and survivors was statistically significant. There was also a trend toward increased levels of P-selectin in the same group of patients, although these differences were not significant. There was no differentiation in either of the two selections when patients were stratified according to ISS or presence of shock.

CONCLUSION

A subset of major trauma patients manifest increased levels of circulating E-selectin adhesion molecules after resuscitation. These patients seem to be at increased risk of death and possibly at risk for infections complications and organ failure. Selectin blockade is a potential new immunomodulatory strategy in this subgroup of patients.

Acute lung injury in endotoxemic rats is associated with sustained circulating IL-6 levels and intrapulmonary CINC activity and neutrophil recruitment--role of circulating TNF-alpha and IL-beta?

Endotoxemia initiates a cytokine response that is thought to mediate the syndromes of sepsis and multiple organ failure. This study measured cytokine levels in the blood and airways of rats at critical time points during the development of lung injury induced by chronic endotoxin (LPS) infusion in the rat. Tumor necrosis factor-alpha (TNF), interleukin-1-beta (IL-1), and interleukin-6 (IL-6) were measured in the blood and bronchoalveolar lavage fluid (BALF) of endotoxemic and control animals. BALF was also studied for the percentage of neutrophil (PMN) count and chemotactic activity. Lung histology was determined at 72 h following infusion of LPS. Chronic endotoxemia of > or = 48 h but not < or = 24 h resulted in severe acute lung injury (ALI). Circulating levels of TNF and IL-1 were only transiently elevated, whereas IL-6 remained elevated in the endotoxemic rats. TNF, IL-1, and IL-6 levels in BALF were only transiently elevated. Chemotactic activity, levels of cytokine-induced neutrophil chemoattractant (CINC), and the percentage of PMN counts in BALF all increased significantly by 36 h. Other potential chemoattractants; leukotriene B4 and transforming growth factor-beta were not elevated in BALF. In conclusion, severe ALI requires a minimum of 48 h LPS infusion in this model and is associated with high levels of circulating IL-6, increased CINC activity, and an increased percentage of PMN count in BALF. Local inflammatory events may be as important as the systemic cytokine milieu in mediating ALI. The signal for these local events does not appear to depend solely on the transient elevations of circulating TNF and IL-1 at the onset of endotoxemia, although sustained high levels of IL-6 may be important.

A prospective evaluation of abdominal ultrasound in blunt trauma: is it useful?

OBJECTIVE

The purpose of this study is to evaluate the utility and feasibility of abdominal ultrasound (US) in blunt trauma patients.

DESIGN

This prospective study examined the operational issues and the diagnostic accuracy of US in selected blunt trauma patients triaged to a Level 1 trauma center.

MATERIALS AND METHODS

All patients were evaluated by an attending trauma surgeon and our usual criteria for objective evaluation of the abdomen were applied. US was performed by US technicians and interpreted by the trauma surgeon. We prospectively evaluated the availability (time to arrival), the ease with which the US could be integrated into the resuscitation (minutes to start after arrival), and the time required to perform the study. The US results were compared to diagnostic peritoneal lavage and computed tomography findings, clinical course, operative findings, and to repeat US examinations to determine sensitivity, specificity, and usefulness.

MEASUREMENTS AND MAIN RESULTS

A total of 800 US studies were performed over 15 months. In four cases (0.5%), the US was incomplete for technical reasons. The results in the remaining 796 studies were as follows: [table: see text] The average time to arrival of the US was 17.3 minutes (range 0-120) and the average minutes to start after arrival was 7.0 (range 1-49). The average time required to perform the study was 10.6 minutes (range 2-26).

CONCLUSIONS

This study demonstrates that US can be obtained rapidly, integrated into the resuscitation, and completed quickly. US provides a highly accurate, noninvasive method to evaluate the abdomen in the blunt trauma patient, and has supplanted the previously used methods at this institution.

Transient systolic hypotension. A serious problem in the management of head injury

OBJECTIVE

To determine the frequency and clinical impact of transient systolic hypotension (systolic blood pressure < 100 mm Hg) in patients with severe anatomic head injury.

DESIGN

Retrospective case-control study.

SETTING

Urban level 1 trauma center.

PATIENTS

Consecutive trauma patients admitted to the intensive care unit (ICU) with severe anatomic head injury, defined as Head and Neck Abbreviated Injury Scale Score of 4 or higher. One thousand thirteen trauma patients were admitted to the ICU during the study period, 157 of whom met inclusion criteria.

MAIN OUTCOME MEASURES

Acute mortality, defined as death during initial ICU admission, and functional status of ICU survivors, assessed as level of function sufficient for discharge to home.

RESULTS

One hundred fifty-seven patients with severe head injury had a total of 831 episodes of systolic hypotension. Fifty-five percent of the patients suffered at least one event. Patients were grouped by total number of low systolic blood pressure events and by average number of events per ICU day. The total number of hypotensive events was associated with increased mortality rates and decreased rate of discharge to home. Average daily frequency of events was associated with increased mortality rates. After stratification by admission Glasgow Coma Scale score, the effects were most dramatic in patients with an initial Glasgow Coma Scale score higher than 8.

CONCLUSIONS

Transient hypotension is common in the ICU and is associated with increased acute mortality and decreased functional status in patients with head injury. The impact of this secondary insult is greatest in patients with less severe primary injury. Strict avoidance of hypotension through enhanced monitoring and active treatment appears to be important, especially in patients with higher presenting Glasgow Coma Scale scores.

A risk analysis of stress ulceration after trauma

Prophylaxis for stress ulceration is considered standard care for most critically ill patients, but may be overutilized. We determined the incidence of stress ulceration in 33,637 major trauma patients treated in a regionalized trauma system from 1985 to 1991 using trauma registry data and chart review. Injury-related risk factors for stress ulceration and other associated infectious and organ failure complications were identified by regression analysis. Clinical stress ulceration developed in 57 patients (0.17%) despite prophylaxis. Eighteen patients (0.05%) developed severe ulceration with either gastroduodenal perforation (3 patients) or a > 2 U blood transfusion requirement (16 patients). Independent risk factors with odds ratios (OR) were identified as follows: Injury Severity Score (ISS) > or = 16, OR = 12.6; spinal cord injury, OR = 2.0; and age > 55, OR = 2.4. Other serious complications, including pneumonia, sepsis, and organ failure (adult respiratory distress syndrome and renal and hepatic failure), were significantly associated with the development of stress ulceration. Clinically significant stress ulceration after trauma is uncommon, but occurs despite prophylaxis. Severe injury (ISS > 16) and spinal cord injury were identified as independent injury-related risk factors. All patients with severe ulceration had either one of these injury-related risk factors or a significant infectious complication or organ failure. Standard prophylaxis may be inadequate in high-risk patients, who should be targeted for increased surveillance and aggressive prophylaxis. On the other hand, routine prophylaxis in low-risk patients may be overutilized.

Use of computed tomography of the head in the hypotensive blunt-trauma patient

STUDY OBJECTIVE

To identify patients presenting with hypotension due to blunt trauma who should undergo computed tomography (CT) of the head before urgent chest or abdominal operation.

DESIGN

Retrospective registry-based record review.

SETTING

Urban Level I trauma center.

PARTICIPANTS

Consecutive trauma patients with suspected head injury, blunt mechanism of injury, and hypotension who were discharged between January 1, 1989, and December 31, 1991. Patients who were dead on arrival or died within 15 minutes of arrival were judged unsalvageable and excluded. Review of 3,224 trauma patients identified 212 as the study population.

INTERVENTIONS

Frequency of neurosurgical intervention or general surgical intervention within 6 hours of admission and the time required for completion of CT of the head were noted.

RESULTS

Overall, 40 general surgical operations (19%) and 16 craniotomies (8%) were performed, with a mortality rate of 18%. Patients with Glasgow Coma Scale scores of less than 8 had a 19% rate of craniotomy, and those with scores between 8 and 13 had a 9% rate. Sixteen patients had CT before surgery, with an average delay of 68 minutes. No patient who responded to initial resuscitation experienced hemodynamic instability in the CT suite, including 15 patients with positive diagnostic peritoneal lavage.

CONCLUSION

CT scan of the head before general surgical operation appears to be safe in patients who respond to initial resuscitation. The likelihood of craniotomy in patients with Glasgow Coma Scale scores of 13 or less is comparable to the likelihood of general surgical operation. Physicians should be encouraged to make CT of the head a high priority in this group.

Risk factors associated with pulmonary embolism despite routine prophylaxis: implications for improved protection

Despite prophylaxis, pulmonary embolism (PE) remains a major cause of posttraumatic morbidity and mortality in high-risk patients. We studied injury-related risk factors associated with the occurrence of PE despite routine prophylaxis. A review of 9721 trauma patients discharged from January 1, 1985 through December 31, 1992, identified 36 patients (0.4%) who suffered clinically evident PE despite a policy of routine prophylaxis against deep venous thrombosis that included use of prophylactic inferior vena caval filters. (Twenty-nine patients had an inferior vena caval filter placed for prophylaxis against PE.) A detailed analysis of injury-related risk factors was performed. Four high-risk patterns of injury were identified, representing common combinations of significant risk factors. These patient groups have an absolute risk of PE despite prophylaxis ranging from 1.5% to 3.8%. The relative risk is approximately ten times that of control patients. Identification of appropriate high-risk groups is necessary to allow optimization of prophylactic measures, including placement of inferior vena caval filter.

Analysis of recurrent process errors leading to provider-related complications on an organized trauma service: directions for care improvement

Complications in trauma care occur because of provider-related or patient disease-related events. Strictly defined standardized definitions of both types of complications are needed to develop strategies for problem resolution. The frequency and characteristics of 135 disease-related and provider-related complications were examined for a 3-year period in a level I university trauma service in all patients meeting Major Trauma Outcome Study (MTOS) criteria. Provider-related complications were analyzed for recurrent process errors to be targeted for corrective action. Complication events occurred in 2764 of 3327 patients, with provider-related complications in 759. Twenty-three percent (175) of complications were judged unjustified and 16 patterns of recurrent process-of-care errors were identified. Delay in trauma team activation was caused by insensitivity of field triage protocols and inadequate recognition of injury patterns. Delays in diagnosis or surgery were caused by inadequate performance of standard work-up, inadequate recognition of injury severity by providers, diagnostic procedure interpretation errors, and errors in prioritizing the order of diagnostic procedures. Errors in technique were attributed to inexperience, haste, unfamiliarity with devices, lack of developed institutional techniques, and failure of providers to use recognized endpoints. Errors in judgment were attributed to failure to access available patient information, proceeding despite available information, and failure to utilize available care guidelines. Further reduction in provider-related morbidity in an organized trauma system requires this type of analysis, which identifies the need to change the process of care through education or adjustment of protocols for standardization care delivery in addition to the traditional focus on outcomes.

A risk analysis of pulmonary complications following major trauma

Varying institutional definitions and degrees of surveillance limit awareness of the true incidence of posttraumatic pulmonary complications. Prospective review with standardized definitions of 25 categories of pulmonary complications was applied to a university level I trauma service over 3 years to establish the true incidence. Potential injury-related predictors of individual complications were determined using multiple logistic regression analysis and adjusted odds ratios were calculated, thereby controlling for the effect of other covariants. Significance was attributed to p < 0.05. Of 3289 patients meeting MTOS criteria, pulmonary complications occurred in 368 (11.2%). Pulmonary complications account for one third of all disease complications. Significant associations with pneumonia included age, the presence of shock on admission, significant head injury, and surgery to the head and chest. Significant risk for atelectasis occurred in patients with blunt injury mechanism, ISS > 16, shock on admission, and severe head injury. Risks for development of respiratory failure included age > 55 years, the mechanism of "pedestrian struck", and the presence of significant head injury. Risk factors for ARDS included surgery to the head and a Trauma Score < 13 on arrival. Significant predictors for pulmonary embolism included ISS > 16, shock on admission, and extremity and pelvis injuries. The true incidence of pulmonary complications is established with this kind of analysis and focuses attention on (1) groups at high risk for developing complications, (2) groups for which current therapeutic modalities are still ineffective, and (3) defining the need to refocus on prospective research rather than ineffective processes of care.

Gangrenous cholecystitis as a complication of hepatic artery embolization: case report

Ischemic injury to the gallbladder has been described after hepatic artery embolization but has not been considered a clinically significant complication of this procedure. We present three cases in which therapeutic embolization resulted in symptomatic gangrenous cholecystitis requiring urgent surgical intervention. Clinical parameters that distinguish this infrequent ischemic septic process from the more common postembolization syndrome are discussed and recommendations concerning the diagnosis and management of these complicated patients are outlined.

Pulmonary effects of continuous endotoxin infusion in the rat

A major hindrance to the elucidation of the pathogenesis of the adult respiratory distress syndrome (ARDS) is the lack of an animal model consistent with the clinical course in humans. A continuous intravenous infusion of endotoxin (LPS) over a several day period was used to more closely parallel the clinical setting. Male Sprague-Dawley rats infused with LPS via indwelling right atrial catheters become tachypneic, lethargic and anorectic with a steady loss in body weight. Serial blood gas analyses demonstrate an early respiratory alkalosis followed by increasing acidosis and hypoxia. Lungs demonstrate 1) pulmonary leukoaggregation, 2) interstitial and intraalveolar edema, 3) Type I pneumocyte injury, 4) proliferation of Type II pneumocytes, and 5) thickening of the microvascular walls. Differential neutrophil count in bronchoalveolar lavage (BAL) fluid increased from 1% to a peak of 59.1% +/- 3.0% and protein content was elevated. A prolonged infusion of LPS in the rat produces a lung injury which mimics many of the pathophysiologic and histologic features associated with sepsis-induced ARDS in humans.

Neutrophil function in a rat model of endotoxin-induced lung injury

Polymorphonuclear neutrophil leukocytes (PMNs) are known to cross the alveolar-capillary barrier and enter the alveolus in acute adult respiratory distress syndrome (ARDS). The pathogenic role of PMNs in both the acute lung injury and subsequent infectious susceptibility in ARDS is not clear. In the present study we investigated the functional status of various neutrophil populations using a chronic, endotoxemia-induced ARDS model. Rats infused with Escherichia coli endotoxin for three days develop an acute lung injury with a histologic picture closely resembling human ARDS. The PMNs recovered from the circulation and by bronchoalveolar lavage were compared with normal rat PMNs. In endotoxemic animals, superoxide production was markedly enhanced in circulating PMNs, indicating production of high levels of potentially cytotoxic oxygen intermediates, while myeloperoxidase activity was decreased in both circulating and lavage PMNs, indicating depressed myeloperoxidase-dependent antimicrobial activity.