The efficacy and limitations of transarterial embolization for severe hepatic injury

BACKGROUND: The efficacy of transarterial embolization (TAE) for severe blunt hepatic injury has been reported. We performed a prospective study evaluating the efficacy and the limitation of TAE from January 1996 to December 2000. METHODS: All patients with blunt abdominal injury who could be stabilized by fluid resuscitation underwent computed tomographic (CT) scan examinations. Patients with CT scan evidence of hepatic injury were classified into five grades according to CT scan findings on the basis of the injury scale of the American Association for the Surgery of Trauma (Mirvis classification). All patients with CT scan grade 3 to 5 injury underwent angiography. When angiography showed extravasation of contrast medium extending from hepatic arterial branches, TAE was performed. RESULTS: Of 612 patients with blunt abdominal trauma, 51 had CT scan grade 3 to 5 injury. Thirty-seven of these patients had a CT scan grade 3 injury and 18 underwent TAE. One of 19 patients who did not undergo TAE developed a delayed hemorrhage on day 6 and required a laparotomy. All 13 patients with a CT scan grade 4 injury had angiographic findings of the extravasation. TAE was successful in 11 patients and unsuccessful in 2. Five patients with a CT scan grade 4 injury required laparotomy. One developed a delayed hemorrhage on day 4. The remaining four patients had a major venous injury (a right lobectomy was performed in two with inferior vena cava injury, and a gauze packing in two with hepatic venous injury). One patient with a CT scan grade 5 injury underwent immediate laparotomy after TAE. Laparotomy revealed inferior vena cava injury and a right lobectomy was performed. Only two patients who underwent a lobectomy died of an uncontrollable hemorrhage. All CT scans of patients with hepatic venous or inferior vena cava injury showed a large low-density area (> or = 10 cm) with involvement of these vessels. The volumes of fluid resuscitation needed from admission until TAE ranged from 2,109 to 2,638 mL/h. CONCLUSION: It was considered that the combination of the presence of a CT scan grade 4 or 5 lesion and the fluid requirements of more than 2,000 mL/h to maintain normotension indicated the absolute necessity of surgery. We felt that these patients were not candidates for TAE, and should undergo immediate laparotomy.     

Small-bowel and mesentery injuries in blunt trauma.

BACKGROUND: The purpose of this study was to identify factors that would aid in the diagnosis of small-bowel and mesentery injuries (SBMI) in blunt trauma patients. METHODS: Retrospective review of 15,779 blunt trauma patients admitted to a Level I trauma center between January 1991 and December 1996. RESULTS: A total of 5,303 patients sustained abdominal injuries, 70 of whom had more than 111 SBMI. Seventy-nine percent were victims of motor vehicle collisions. Thirty patients had isolated SBMI and 40 had associated intra-abdominal injuries. Twelve patients arrived with systolic blood pressure < 90 mm Hg, eight of whom died. Mean base deficit was -7.3 +/- 6.3 in 52 patients who had arterial blood gases determined. Fifty-three of 60 patients had hematuria. Sixty-seven patients required laparotomy. Delayed exploration occurred in 15 patients who underwent initial computed tomography but had subsequent changes in physical status. Two of 20 patients had negative diagnostic peritoneal lavage on admission and were eventually explored based on abdominal computed tomographic findings and changes in physical examination. There were 15 deaths. Delay in diagnosis (>12 hours after arrival) occurred in nine patients with no deaths or significant morbidities. Mean Injury Severity Score was 29 +/- 16.7: 43 +/- 17 in nonsurvivors and 25 +/- 14.3 in survivors (p < 0.05). CONCLUSION: The diagnosis of SBMI is often made in the presence of associated intra-abdominal injuries. Isolated SBMI are common, however, and special attention to the mechanism of injury, abdominal examination, presence of hematuria, and significant base deficit should raise suspicion to the possibility of SBMI. Findings on abdominal computed tomography that may suggest SBMI and should prompt further evaluation include free fluid, thickened bowel, and extraluminal air. Because delay in diagnosis does not seem to affect morbidity or mortality, dedication to observation and serial physical examinations will aid in the proper identification of elusive SBMI. Mortality, however, does appear to be related to the presence of hypotension on admission and associated injuries.     

Use of splenic artery embolization as an adjunct to nonsurgical management of blunt splenic injury

BACKGROUND: Splenic artery embolization (SAE) has been used as an adjunct to the nonsurgical treatment of blunt splenic injuries since 1981. It is imperative to define the role of SAE in the management of splenic trauma and to establish a guideline for its use. METHODS: In this study, 39 consecutive patients with blunt splenic ruptures were evaluated. All the patients were treated according to the authors' protocol, which included SAE as an adjunct. Angiographic study was performed for patients with any of the following presentations: recurrent hypotension despite fluid resuscitation, significant hemoperitoneum or extravasation of contrast media on computed tomography, grade 4 or 5 splenic injury, or progressive need for blood transfusion. Laparotomy was reserved for patients with unstable hemodynamics or failure of SAE. RESULTS: Four patients were excluded from the study, and 6 of the 35 remaining patients (male-to-female ratio, 22:13) received SAE. One of the six SAE patients underwent operation because of persistent hemorrhage after SAE. Nonoperative treatment was successful for 31 patients. Splenic artery embolization increased the success rate for nonsurgical management from 74% (26 of 35 patients) to 89% (31 of 35 patients). CONCLUSIONS: Judicious use of SAE for patients with blunt splenic injury avoids unnecessary surgery and expands the number of patients who can retain their spleen.     

Hyperacute abdominal compartment syndrome: an unrecognized complication of massive intraoperative resuscitation for extra-abdominal injuries

Primary and secondary abdominal compartment syndrome (ACS) are well-recognized entities after trauma. The current study describes a "hyperacute" form of secondary ACS (HACS) that develops intraoperatively while repair of extra-abdominal injuries is being carried out simultaneous with massive resuscitation for shock caused by those injuries. The charts of patients requiring abdominal decompression (AD) for HACS at time of extra-abdominal surgery at our level I trauma center were reviewed. The following data was gathered: age, Injury Severity Score (ISS), mechanism, resuscitation details, time to AD, time to abdominal closure, and outcome. All continuous data are presented as mean +/- standard error of mean. Hemodynamic and ventilatory data pre- and post-AD was compared using paired t test with significance set at P < 0.05. Five (0.13%) of 3,750 trauma admissions developed HACS during the 15-month study period ending February 2004. Mean age was 32 +/- 7 years, and mean ISS was 19 +/- 2. Four of five patients arrived in hemorrhagic shock (blunt subclavian artery injury, 1; chest gunshot, 1; gunshot to brachial artery, 1; stab transection of femoral vessels, 1) and were immediately operated upon. One of five patients (70% burn) developed HACS during burn wound excision on day 2. HACS developed after massive crystalloid (15 +/- 1.7 L) and blood (11 +/- 0.4 units) resuscitation during prolonged surgery (4.8 +/- 0.8 hours). Pre- versus post-AD comparisons revealed significant (P < 0.05) improvements in mean arterial pressure (55 +/- 6 vs 88 +/- 3 mm Hg), peak airway pressure (44 +/- 5 vs 31 +/- 2 mm Hg), tidal volume (432 +/- 96 vs 758 +/- 93 mL), arterial pH (7.16 +/- 0.0 vs 7.26 +/- 0.04), and PaCO2 (52 +/- 6 vs 45 +/- 6 mm Hg). There was no mortality among the group, and all patients underwent abdominal closure by fascial reapproximation in 2-5 days. Two (40%) of the five patients required extremity fasciotomy for compartment syndrome. HACS is a rare complication of massive resuscitation for extra-abdominal injuries. It should be considered in such patients in the face of unexplained hemodynamic and/or ventilatory decompensation. Prompt AD is life saving. Early abdominal closure is usually possible. Vigilance for compartment syndromes elsewhere in the body is warranted in any patient with HACS.)     

Treatment of uncontrolled hemorrhagic shock after liver trauma: fatal effects of fluid resuscitation versus improved outcome after vasopressin

In a porcine model of uncontrolled hemorrhagic shock, we evaluated the effects of vasopressin versus an equal volume of saline placebo versus fluid resuscitation on hemodynamic variables and short-term survival. Twenty-one anesthetized pigs were subjected to severe liver injury. When mean arterial blood pressure was <20 mm Hg and heart rate decreased, pigs randomly received either vasopressin IV (0.4 U/kg; n = 7), an equal volume of saline placebo (n = 7), or fluid resuscitation (1000 mL each of lactated Ringer's solution and hetastarch; n = 7). Thirty minutes after intervention, surviving pigs were fluid resuscitated while bleeding was surgically controlled. Mean (+/- SEM) arterial blood pressure 5 min after the intervention was significantly (P < 0.05) higher after vasopressin than with saline placebo or fluid resuscitation (58 +/- 9 versus 7 +/- 3 versus 32 +/- 6 mm Hg, respectively). Vasopressin improved abdominal organ blood flow but did not cause further blood loss (vasopressin versus saline placebo versus fluid resuscitation 10 min after intervention, 1343 +/- 60 versus 1350 +/- 22 versus 2536 +/- 93 mL, respectively; P < 0.01). Seven of 7 vasopressin pigs survived until bleeding was controlled and 60 min thereafter, whereas 7 of 7 saline placebo and 7 of 7 fluid resuscitation pigs died (P < 0.01). We conclude that vasopressin, but not saline placebo or fluid resuscitation, significantly improves short-term survival during uncontrolled hemorrhagic shock. IMPLICATIONS: Although IV fluid administration is the mainstay of nonsurgical management of trauma patients with uncontrolled hemorrhagic shock, the efficacy of this strategy has been discussed controversially. In this animal model of severe liver trauma with uncontrolled hemorrhagic shock, vasopressin, but not saline placebo or fluid resuscitation, improved short-term survival.     

Combined hemorrhagic shock and head injury: effects of hypertonic saline (7.5%) resuscitation

Hypertonic saline resuscitation was compared to isotonic fluid resuscitation in a large animal model combining hemorrhagic shock with head injury. Sheep were subjected to a freeze injury of one cerebral hemisphere as well as 2 hours of hypotension at a mean arterial pressure (MAP) of 40 mm Hg. Resuscitation was then carried out (MAP = 80 mm Hg) for 1 hour with either lactated Ringer's (LR, n = 6) or 7.5% hypertonic saline (HS, n = 6). Hemodynamic parameters and intracranial pressure (ICP) were followed. At the end of resuscitation brain water content was determined in injured and uninjured hemispheres. No differences were detected in cardiovascular parameters; however, ICPs were lower in animals resuscitated with HS (4.2 +/- 1.5 mm Hg) compared to LR (15.2 +/- 2.2 mm Hg, p less than 0.05). Additionally, brain water content (ml H2O/gm dry weight) in uninjured brain hemispheres was lower after HS resuscitation (HS = 3.3 +/- 0.1; LR = 4.0 +/- 0.1; p less than 0.05). No differences were detected in the injured hemispheres. We conclude that hypertonic saline abolishes increases in ICP seen during resuscitation in a model combining hemorrhagic shock with brain injury by dehydrating areas where the blood-brain barrier is still intact. Hypertonic saline may prove useful in the early management of multiple trauma patients.     

Type II endoleak in porcine model of abdominal aortic aneurysm

PURPOSE: The purpose of this study was to develop a reliable in vivo porcine model of type II endoleak resulting from endovascular aortic aneurysm repair (EVAR), for the study and treatment of type II endoleak. METHODS: Eight pigs underwent creation of an infrarenal aortic aneurysm, with a Dacron patch with preservation of lumbar branches. An indwelling pressure transducer was placed in the aneurysm sac. After 1 week the animals underwent EVAR with a custom-made Talent endograft. After another week the animals underwent laparoscopic lumbar artery ligation. Abdominal and pelvic computed tomography was performed after each procedure. Aneurysm sac pressure was measured in sedated and awake animals. RESULTS: All eight animals underwent successful creation of an aortic aneurysm and EVAR resulting in exclusion of the aneurysm sac. After creation of the aneurysm the sac mean arterial pressure (MAP) was 72.5 +/- 6.1 mm Hg and the sac pulse pressure was 44.8 +/- 8.7 mm Hg. Postoperative computed tomography scans demonstrated a type II endoleak from the lumbar branches in all animals. While aneurysm sac MAP (56.5 +/- 7.9 mm Hg; P <.01) and pulse pressure (13.6 +/- 4.1 mm Hg; P <.01) decreased after EVAR, sac pulse pressure remained, with type II endoleak. All animals underwent laparoscopic lumbar artery ligation, which resulted in further reduction in the sac MAP (38.3 +/- 4.6 mm Hg; P <.02) and immediate absence of sac pulse pressure (0 mm Hg; P <.01). Necropsy confirmed the absence of collateral flow in the aneurysm sac, with fresh thrombus formation in all animals. CONCLUSION: We present a reliable and clinically relevant in vivo large animal model of type II endoleak. CLINICAL RELEVANCE: We set out to show that aortic aneurysm sac pressurization caused by lumbar arterial flow in the setting of type II endoleak can be reproduced in an in vivo porcine model of endovascular aortic aneurysm repair. Indeed, in this model the aneurysm sac pulse pressure was a sensitive indicator of type II endoleak, correlating well with findings at computed tomography, and lumbar artery ligation eliminated the endoleak, as demonstrated on computed tomography scans and sac pressure measurement. Therefore we believe this in vivo large animal model can be instrumental in the study of many aspects of the physiologic features of type II endoleak.     

Pediatric blunt liver injury: establishment of criteria for appropriate management

There is no consensus regarding the most appropriate management of pediatric blunt liver injury. This study addresses this issue by reviewing our experience with blunt liver trauma in relationship to the grade of injury. Forty-one pediatric patients with blunt abdominal trauma and documented liver injury were managed from 1979 to 1989. Fifteen (37%) underwent celiotomy. Three children had extensive parenchymal injuries (grade IV or V) requiring resection and three others died intraoperatively, secondary to exsanguinating hemorrhage of associated injuries (grade V) to the hepatic veins and inferior vena cava. The need for celiotomy was obvious in these patients. In 9 of the 15 children who underwent exploration (60%), bleeding from the liver injury (grade II or III) had ceased by the time of celiotomy. These children did not appear to benefit from the operation. Twenty-six of the 41 patients (63%) were selected for nonoperative management because they were hemodynamically stable after initial resuscitation and did not show signs of associated intraabdominal injuries requiring surgical intervention. These children underwent evaluation by abdominal computed axial tomography scan (grade I, II, III, and IV injuries). Blood transfusions were given to keep the hematocrit above 30%. Seventeen of the 26 children managed nonoperatively (65%) did not require blood replacement. The mean (+/- SEM) transfusion volume for the remaining nine children was 14.8 +/- 2.5 mL/kg. Blunt liver injury represents a spectrum from a minimal parenchymal hematoma to massive liver disruption. We conclude that celiotomy is necessary for hepatic injury hemodynamically stable injured children with transfusion requirements less than 40 mL/kg can be managed nonoperatively in an appropriate setting.     

Helical computed tomography of bowel and mesenteric injuries

BACKGROUND: The role of computed tomography in diagnosing hollow viscus injury after blunt abdominal trauma remains controversial, with previous studies reporting both high accuracy and poor results. This study was performed to determine the diagnostic accuracy of helical computed tomography in detecting bowel and mesenteric injuries after blunt abdominal trauma in a large cohort of patients. METHODS: One hundred fifty patients were admitted to our Level I trauma center over a 4-year period with computed tomographic (CT) scan or surgical diagnosis of bowel or mesenteric injury. CT scan findings were retrospectively graded as negative, nonsurgical, or surgical bowel or mesenteric injury. The CT scan diagnosis was then compared with surgical findings, which were also graded as negative, nonsurgical, or surgical. RESULTS: Computed tomography had an overall sensitivity of 94% in detecting bowel injury and 96% in detecting mesenteric injury. Surgical bowel cases were correctly differentiated in 64 of 74 cases (86%), and surgical mesenteric cases were correctly differentiated from nonsurgical in 57 of 76 cases (75%). CONCLUSION: Helical CT scanning is very accurate in detecting bowel and mesenteric injuries, as well as in determining the need for surgical exploration in bowel injuries. However, it is less accurate in predicting the need for surgical exploration in mesenteric injuries alone.     

Iliac vein injuries in hemodynamically unstable patients with pelvic fracture caused by blunt trauma

BACKGROUND: Major pelvic venous injuries secondary to blunt trauma can be a difficult problem in diagnosis and management. This study aimed to elucidate the clinical significance of iliac vein injuries demonstrated by venography in patients with blunt pelvic injuries who remained unstable even after transcatheter arterial embolization (TAE). METHODS: We reviewed the records of 72 patients with unstable pelvic fracture who presented with shock at our center after blunt trauma from 1999 through 2003. The average Injury Severity Score was 34.3 in this study population. RESULTS: TAE was the first method of choice to control bleeding from pelvic fracture in 61 patients. Thirty-six patients recovered from shock after TAE. Eighteen of 25 who did not recover from shock died. In 11 of these 25, transfemoral venography with a balloon catheter was performed, revealing significant venous extravasation in 9: common iliac vein in 5, internal iliac vein in 3, and external iliac vein in 1. The average Injury Severity Score of patients with iliac vein injury was 45.8. Treatments for venous injuries were laparotomy for hemostasis (n = 1, survivors = 0), retroperitoneal gauze packing (n = 3, survivors = 1), and endovascular stent placement (n = 3, survivors = 3). Two patients suffered from cardiac arrest before treatment for venous injury. External fixations were performed after TAE according to fracture type. CONCLUSION: The iliac vein injury is the principal cause of hemorrhagic shock in some patients with unstable pelvic fractures after blunt trauma. Venography is useful for identifying iliac vein injuries.     

Relationship between pseudoaneurysm formation and biloma after successful transarterial embolization for severe hepatic injury: permanent embolization using stainless steel coils prevents pseudoaneurysm formation

OBJECTIVE: The purpose of this study was to determine the association between bilomas and pseudoaneurysm complications after severe hepatic injury. METHODS: Angiography was performed in patients with American Association for the Surgery of Trauma grade > or = III hepatic injury on contrast-enhanced computed tomographic scanning. When contrast extravasation was observed, transarterial embolization (TAE) was performed. After TAE, technetium-99m pyridoxyl-5-methyl-tryptophan cholescintigraphy was performed to detect the coexistence of bilomas. Follow-up angiography was performed when a biloma was detected. Eighty consecutive patients underwent angiography; after angiography, five patients died. The remaining 75 patients who underwent cholescintigraphy were included in this study. RESULTS: All 11 patients who had bilomas had angiographic evidence of contrast extravasation. The biloma frequency was higher in patients with grades IV and V injuries than in those with grade III injury (p = 0.024). Follow-up angiography revealed pseudoaneurysms in 7 of these 11 patients. All six patients in whom only gelatin sponge pledget injection was used to embolize had pseudoaneurysms. Among them, two patients had computed tomographic evidence of massive intra-abdominal fluid collection. In contrast, only one of five patients who received the combination of gelatin sponge pledget injection and stainless steel coils to permanently embolize injured arteries had a pseudoaneurysm. In this patient, the pseudoaneurysm was found in the peripheral part of the collateral vessels. All patients with pseudoaneurysms underwent repeat TAE and were discharged from the hospital uneventfully. CONCLUSION: In patients with high-grade hepatic injury and arterial bleeding who developed biloma, use of a gelatin sponge, an absorbable embolic material, is associated with a risk of pseudoaneurysm formation. Permanent arterial embolization using stainless steel coils is indicated to decrease this risk.     

Computed tomography and diagnostic peritoneal lavage in blunt abdominal trauma. Their combined role

We reviewed medical records and films of all 196 trauma patients who underwent computed tomography (CT) between June 1982 and October 1986 to see whether CT achieved the level of accuracy attributed to it, whether diagnostic peritoneal lavage (DPL) performed in conjunction with CT was a useful diagnostic test for blunt abdominal trauma, and whether laparotomy was mandatory when pelvic fluid collections were seen by CT after blunt trauma. A total of 36 patients underwent DPL, 29 before and seven after CT. There were seven false-negative CTs that were clinically significant. Diagnostic peritoneal lavage was positive in three patients who had false-negative CTs. Although overall accuracy was excellent, CT was not reliable in detecting bowel injury. Diagnostic peritoneal lavage was helpful in detecting injuries missed by CT. Most stable patients with moderate or large intraperitoneal fluid collections on CT accompanying solid viscus injury were treated successfully without laparotomy.     

A comparison of lactated ringer's solution to hydroxyethyl starch 6% in a model of severe hemorrhagic shock and continuous bleeding in dogs

In this randomized, controlled study in dogs, we examined the short-term effects of blood pressure targeted fluid resuscitation with colloids or crystalloids solutions on systemic oxygen delivery, and lactate blood concentration. Fluid resuscitation using hydroxyethyl starch (HES) 6% to a mean arterial blood pressure (MAP) of 60 mm Hg was compared with lactated Ringer's solution (LR) to a MAP of 60 or 80 mm Hg (LR60 and LR80, respectively). The model was one of withdrawal of blood to a MAP of 40 mm Hg through an arterial catheter that was then connected to a system allowing bleeding to occur throughout the study whenever MAP exceeded 40 mm Hg. Target MAP was maintained for 60 min with a continuous infusion of the designated fluid replacement. All 15 dogs (5 in each group) survived until the last measurement. Blood loss in the LR80 group (2980 +/- 503 mL) (all values mean +/- SD) was larger than in the LR60 and HES60 groups (1800 +/- 389 mL, and 1820 +/- 219 mL, respectively) (P < 0.001). Whereas 840 +/- 219 mL of HES60 was needed to maintain target MAP, 1880 +/- 425 mL of LR was needed in the LR60 group, and 4590 +/- 930 mL in the LR80 group (P < 0.001). Lactate blood concentrations were smaller and delivered O(2) higher in the HES60 group (35 +/- 17 mg/dL and 239 +/- 61 mL/min, respectively) in comparison to the LR60 group (89 +/- 18 mg/dL and 140 +/- 48 mL/min, respectively) and the LR80 group (75 +/- 23 mg/dL and 153 +/- 17 mL/min, respectively) (P = 0.02 and P = 0.026). In conclusion, fluid resuscitation during uncontrolled bleeding, to a target MAP of 60 mm Hg, using HES60 resulted in larger oxygen delivery and smaller systemic lactate A resuscitation to a target MAP of 60 or 80 mm Hg using LR. IMPLICATIONS: Fluid resuscitation to a target mean arterial blood pressure of 60 mm Hg during uncontrolled bleeding resulted in larger oxygen delivery and smaller systemic lactate concentrations when hydroxyethyl starch 6% was used, in comparison to lactated Ringer's solution resuscitation to a target mean arterial blood pressure of 60 or 80 mm Hg.     

Secondary abdominal compartment syndrome is an elusive early complication of traumatic shock resuscitation

BACKGROUND: The term secondary abdominal compartment syndrome (ACS) has been applied to describe trauma patients who develop ACS but do not have abdominal injuries. The purpose of this study was to describe major trauma victims who developed secondary ACS during standardized shock resuscitation. METHODS: Our prospective database for standardized shock resuscitation was reviewed to obtain before and after abdominal decompression shock related data for secondary ACS patients. Focused chart review was done to confirm time-related outcomes. RESULTS: Over the 30 months period ending May 2001, 11 (9%) of 128 standardized shock resuscitation patients developed secondary ACS. All presented in severe shock (systolic blood pressure 85 +/- 5 mm Hg, base deficit 8.6 +/- 1.6 mEq/L), with severe injuries (injury severity score 28 +/- 3) and required aggressive shock resuscitation (26 +/- 2 units of blood, 38 +/- 3 L crystalloid within 24 hours). All cases of secondary ACS were recognized and decompressed within 24 hours of hospital admission. After decompression, the bladder pressure and the systemic vascular resistance decreased, while the mean arterial pressure, cardiac index, and static lung compliance increased. The mortality rate was 54%. Those who died failed to respond to decompression with increased cardiac index and did not maintain decreased bladder pressure. CONCLUSIONS: Secondary ACS is an early but, if appropriately monitored, recognizable complication in patients with major nonabdominal trauma who require aggressive resuscitation.     

Hypotensive resuscitation during active hemorrhage: impact on in-hospital mortality

BACKGROUND: Traditional fluid resuscitation strategy in the actively hemorrhaging trauma patient emphasizes maintenance of a normal systolic blood pressure (SBP). One human trial has demonstrated improved survival when fluid resuscitation is restricted, whereas numerous laboratory studies have reported improved survival when resuscitation is directed to a lower than normal pressure. We hypothesized that fluid resuscitation titrated to a lower than normal SBP during the period of active hemorrhage would improve survival in trauma patients presenting to the hospital in hemorrhagic shock. METHODS: Patients presenting in hemorrhagic shock were randomized to one of two fluid resuscitation protocols: target SBP > 100 mm Hg (conventional) or target SBP of 70 mm Hg (low). Fluid therapy was titrated to this endpoint until definitive hemostasis was achieved. In-hospital mortality, injury severity, and probability of survival were determined for each patient. RESULTS: One hundred ten patients were enrolled over 20 months, 55 in each group. The study cohort had a mean age of 31 years, and consisted of 79% male patients and 51% penetrating trauma victims. There was a significant difference in SBP observed during the study period (114 mm Hg vs. 100 mm Hg, p < 0.001). Injury Severity Score (19.65 +/- 11.8 vs. 23.64 +/- 13.8, p = 0.11) and the duration of active hemorrhage (2.97 +/- 1.75 hours vs. 2.57 +/- 1.46 hours, p = 0.20) were not different between groups. Overall survival was 92.7%, with four deaths in each group. CONCLUSION: Titration of initial fluid therapy to a lower than normal SBP during active hemorrhage did not affect mortality in this study. Reasons for the decreased overall mortality and the lack of differentiation between groups likely include improvements in diagnostic and therapeutic technology, the heterogeneous nature of human traumatic injuries, and the imprecision of SBP as a marker for tissue oxygen delivery.     

Leukocytosis and free fluid are important indicators of isolated intestinal injury after blunt trauma

BACKGROUND: The detection of isolated intestinal injuries after blunt trauma can be difficult because of subtle signs and symptoms, often leading to delayed diagnosis. We hypothesized that specific clinical indicators could be identified to assist in the diagnosis of these injuries. METHODS: Medical records of all patients with such injuries from 1988 to 1996 were reviewed. The patients were stratified into those operated on within 6 hours of presentation (apparent injury) and those operated on after 6 hours (occult injury), and the data were compared. RESULTS: Forty-six patients with isolated intestinal injuries were identified. There were no differences in the rate of peritonitis or free fluid on abdominal computed tomography, blood loss, intraoperative findings, or morbidity and mortality between groups. Leukocytosis (sensitivity, 84.8%; specificity, 55.2%; p = 0.01) and free fluid on computed tomography were frequently present, however, and their significance was underappreciated in the occult injury group. CONCLUSION: After blunt abdominal trauma in patients without obvious indications for invasive evaluation of the abdomen (e.g., peritoneal lavage, laparoscopy, laparotomy), leukocytosis can indicate an intestinal injury. Additionally, unexplained free fluid on abdominal computed tomography must be aggressively evaluated.     

Large volume crystalloid resuscitation does not increase extravascular lung water

The purpose of this study was to determine whether Ringer's lactate solution increases extravascular lung water (EVLW) during resuscitation after hemorrhagic shock. Ten sheep anesthetized with thiamylal were bled to a mean arterial pressure (MAP) of 50 mm Hg; further bleeding maintained that pressure for 30 min. Resuscitation fluid consisted of Ringer's lactate solution in volumes necessary to restore and maintain for 1 hr MAP, pulmonary capillary wedge pressure (PCWP), and cardiac index at levels equal to those measured before bleeding. After volume replacement, the colloid oncotic pressure (COP) - PCWP gradient (COP - PCWP) decreased from 12 +/- 3 to 2 +/- 5 mm Hg (P less than 0.001). After volume restoration, COP decreased from 19 +/- 8 mm Hg to 12 +/- 2 mm Hg (P less than 0.001). Despite the large volume of fluid administered, EVLW did not increase. Crystalloid resuscitation does not necessarily increase EVLW despite significant decreases in COP and COP - PCWP gradient.     

Monitoring tissue oxygenation during resuscitation of major burns

BACKGROUND: Because subcutaneous and splanchnic oxygenation indices are sensitive indicators of evolving hemorrhagic shock and adequacy of resuscitation, we postulated that these indices might have an equivalent role in the monitoring of severely burned patients. This observational study was undertaken to examine changes in tissue oxygenation indices during burn resuscitation. METHODS: Seven patients with major burns (54 +/- 21% total body surface area) were studied during the first 36 hours of fluid resuscitation. Silastic tubing was placed in the subcutaneous tissue just beneath both normal skin and deep partial thickness burn. Fiberoptic sensors inserted into the tubing measured subcutaneous oxygen and carbon dioxide tensions in the burnt skin (PO2scb and PCO2scb) and normal skin (PO2scn and PCO2scn) continuously. Gastric intramucosal pH (pHi) and the mucosal CO2 (PCO2m) gap were calculated using gastric tonometers. Mean arterial pressure, arterial pH, lactate, and pHi measurements were obtained for 36 hours. RESULTS: There were no significant differences in mean arterial pressure, arterial pH, or lactate concentrations throughout the study period, whereas indices of tissue oxygenation showed deterioration: pHi decreased from 7.2 +/- 0.1 to 6.7 +/- 0.3 (p = 0.06), the PCO2m gap increased from 12 +/- 17 to 108 +/- 123 mm Hg (p < 0.01), PO2scn decreased from 112 +/- 18 to 50 +/- 11 mm Hg (p < 0.01), PO2scb decreased from 62 +/- 23 to 29 +/- 16 mm Hg (p < 0.01), PCO2scn increased from 42 +/- 4 to 46 +/- 10 mm Hg (p = 0.2), and PCO2scb increased from 42 +/- 10 to 52 +/- 5 mm Hg (p = 0.05). CONCLUSION: Despite adequate global indices of tissue perfusion after 36 hours of resuscitation, tissue monitoring indicated significant deterioration in the splanchnic circulation and in the normal and burnt skin.     

Management of ongoing arterial haemorrhage after damage control laparotomy: Optimal timing and efficacy of transarterial embolisation

Introduction

Patients undergoing damage control laparotomy need intensive and aggressive resuscitation, and may also require adjunctive transarterial embolisation (TAE) for ongoing arterial haemorrhage. We evaluated the effectiveness and timing of TAE in these patients as well as their final outcome.

Materials and methods

From January 1998 to December 2006, the case records of 16 patients with ongoing arterial haemorrhages (hepatic haemorrhage = 7, extra-hepatic haemorrhage = 9) who underwent TAE after damage control laparotomy were reviewed. Fourteen patients had blunt injuries and two had penetrating injuries.

Results

There were 13 men and three women. Their ages ranged from 3 to 85 years (mean, 36 years). Of seven hepatic angiograms, contrast extravasation at the right hepatic artery and left hepatic artery was found in three patients each. Bilateral hepatic artery injuries were found in one patient. Of nine extra-hepatic angiograms, the internal iliac artery was the most commonly injured artery (n = 6). After TAE, 14 of 16 ongoing arterial haemorrhages could be controlled and eight patients survived; however, two patients with uncontrolled haemorrhages eventually died (hepatic artery injury = 1, lumbar artery injury = 1). Of 16 patients overall, profound haemorrhagic shock (n = 4) and multiple organ failure (n = 4) resulted in eight deaths (hepatic injury = 4, extra-hepatic injury = 4), and accounted for a mortality rate of 50%. Of 16 patients, nine were taken directly from the operating room to the angiography suite and the mortality rate was 33.3%. The other seven patients were taken to the angiography suite from the intensive care unit and the mortality rate was 71.4%. Of three survivors who underwent hepatic TAE, the operative time ranged from 30 min to 72 min (mean, 48 min). However, of four nonsurvivors who underwent hepatic TAE, the operative time ranged from 58 min to 180 min (mean, 119 min).

Conclusions

TAE is an effective tool in the management of ongoing arterial haemorrhage after damage control laparotomy and eight (50%) patients with ongoing arterial haemorrhages survived from this multidisciplinary treatment. To achieve a good outcome, the operative time of damage control laparotomy should be as short as possible and TAE should be performed without delay. Interventional radiology colleagues should be informed in advance during laparotomy and resuscitation continued in the angiography suite.     

Surgical treatment of liver injury with microwave tissue coagulation: an experimental study

OBJECTIVE: The purpose of this study was to examine whether microwave tissue coagulation (MTC) therapy is capable of stopping bleeding from severe liver injury in pigs. METHODS: Ten pigs (38 +/- 4 kg) underwent a 30-mL/kg isovolemic exchange transfusion with 3% low-molecular-weight dextran to produce dilutional coagulopathy, and then a through-and-through laceration injury measuring approximately 8 cm in length was induced in the right hepatic lobe. Immediately after inflicting the injury, the animals were randomly divided into two groups: Group A (n = 5, MTC was repeated along the liver laceration at intervals of 2.0 cm with manual compression) or Group B (n = 5, the injured lobe was manually compressed without MTC therapy for 1 minute). All animals received lactated Ringer's solution to maintain the mean arterial pressure at 75 mm Hg for 1 hour after the abdominal closure. The intraperitoneal blood loss, mean arterial pressure, volume of lactated Ringer's solution, and hematologic variables were compared between the groups. For further laboratory evaluation, three additional experimental animals were treated with the MTC therapy after inflicting the injury and then were allowed to survive for 14 days. RESULTS: Mean arterial pressure declined from a mean value of 88 +/- 10 mm Hg (range, 75-107 mm Hg) to 62 +/- 3 mm Hg (range, 50-75 mm Hg) after the induction of liver injury. The total blood loss in Group A was 192 +/- 58 g (range, 120-250 g), which was lower (p < 0.01) than that of 448 +/- 138 g (range, 260-650 g) in Group B. The resuscitation fluid volume of Group A animals was 304 +/- 204 mL (range, 100-600 mL), which was smaller (p < 0.01) than that of 1,320 +/- 654 mL (range, 900-2,250 mL) in Group B. At 14 days, all three animals that were treated in the additional study were found to be in good health. Their necropsies showed no evidence of an intrahepatic abscess, hematoma, or biloma. CONCLUSION: MTC therapy was thus found to provide simple, rapid, and definitive hemorrhage control in cases of severe liver injury without the need for reoperation.