Factors determining operative mortality of grade V blunt hepatic trauma

BACKGROUND

Despite recent advances in the management of severe hepatic injuries, the operative mortality rate of grade V hepatic injuries still ranges from 67% to 80%. Grade V hepatic injuries involving the retrohepatic cava or main hepatic veins are almost always lethal, especially those from blunt trauma. The purpose of this study is to understand the risk factors determining operative mortality in grade V blunt hepatic trauma, and to try to improve the surgical management of these injuries.

METHODS

A retrospective study was conducted at a medical center that offers services including primary, secondary, and tertiary care. Forty-four patients with grade V blunt hepatic injuries were treated during a 6-year period from January 1, 1991, to December 31, 1996. The operative mortality was compared by a multivariate analysis.

RESULTS

Forty-four patients with grade V blunt hepatic injuries were identified. Seven patients had only parenchymal injuries, and the others had vascular and associated parenchymal injuries. Venorrhaphy was used in 37 patients; 29 were treated using a nonshunting approach, and 8 with an atriocaval shunt. The overall mortality rate was 68% (30 of 44), and liver-related mortality was 50% (22 of 44). Univariate analysis revealed that the significant variables affecting operative mortality were initial systolic blood pressure, initial base deficit, the Glasgow Coma Scale, injury type, number of resected segments, and total intraoperative blood loss. Based on forward stepping logistic regression analysis, patients with an initial base deficit of -6 mmol/L or less (relative risk = 17.3), and a total intraoperative blood loss of 5,000 mL or more (relative risk = 23.5) would, significantly, encounter a worsening prognosis.

CONCLUSIONS

Initial base deficit and total intraoperative blood loss were the significant factors that determined operative mortality after grade V blunt hepatic trauma. We suggest that prompt resuscitation and expeditious and appropriate surgical management, to control operative blood loss, is the only way to reduce operative mortality in patients with grade V blunt hepatic trauma.

Blunt hepatic injury: minimal intervention is the policy of treatment

BACKGROUND

Many publications recommend nonoperative treatment for stable blunt hepatic injury patients. Unstable hemodynamic status is the only indication for surgery. When operation is indicated, controversies exist regarding which operative procedure will be more beneficial to the patients. The purposes of this study are to compare the results of operative and nonoperative management of patients with blunt hepatic injuries and to identify the optimal surgical approach when surgery is indicated.

METHODS

Different prospective protocols of treating adult blunt hepatic injuries were conducted. From 1992 to 1993 (group I), urgent surgery would be performed in the presence of hemoperitoneum. The policy shifted to aggressive nonoperative approach between 1996 and 1997 (group II). The patients from each period were divided into three subgroups. Group A included the patients who received nonoperative treatment in either period. Group B consisted of the patients who received surgery in the first period and nonoperative management in the second period. Group C included the patients who were operated on in either group. Comparisons were made between matched groups.

RESULTS

Groups IA and IIA patients had minor injuries and could be successfully treated nonoperatively. The results of groups IB and IIB were similar concerning hospital stay, morbidity, and mortality. Transfusion requirements of group IIB patients were significantly higher (2.2 vs. 1.1 units,p = 0.01) than those of group IB. However, 25 (58%) celiotomies of group IB patients were nontherapeutic. When surgery was indicated, group IC patients had significantly higher liver-related mortality (14 of 49 vs. 3 of 55, p = 0.002). Anatomic resection was performed more frequently in that period.

CONCLUSION

Nonoperative treatment significantly decreased the rate of nontherapeutic laparotomy but carried the risks of higher transfusion requirements and delaying operation. When surgery was indicated, the policy of minimal intervention positively affected the patients' outcomes. The goal of surgery should be hemorrhage control rather than resection of the injured liver tissues.

Laparoscopic decompression of abdominal compartment syndrome after blunt hepatic trauma

Abdominal compartment syndrome (ACS) can occur in a variety of surgical conditions, particularly those with major life-threatening hemorrhage, massive volume resuscitation, prolonged operation times, and coagulopathy. In severely traumatized patients, the incidence of ACS is reported to be as high as 14% to 15% after damage control laparotomies. Although favorable results have been achieved with nonsurgical management of adult blunt hepatic trauma, the failure rates still range from 0% to 19%. Exploratory laparotomy is considered the intervention of choice in patients with blunt hepatic trauma who fail nonsurgical treatment. Expedient abdominal decompression currently is the treatment of choice after ACS. Oliguria, tachypnea, and tachycardia developed in two blunt hepatic trauma patients with grade IV and V injuries while they were receiving nonsurgical treatment. The intra-abdominal pressures measured more than 35 and 25 cm H 2O, respectively. Two patients with grade II and III ACS received laparoscopic examination instead of laparotomy. Their ACS was decompressed effectively via laparoscopy without any adverse effects. Therefore, we suggest that laparoscopy can be used as a safe alternative for the decompression of ACS.

[Determination of sialic acids in serum of lung cancer with ultrafiltration-capillary electrophoresis]

A method for the determination of sialic acids in serum with ultrafiltration-capillary electrophoresis is described and the operation was optimized. Sialic acids were directly separated and analyzed with UV detection at 195 nm and without pre-or post-column derivatization. The recovery of N-acetylneuraminic acid (NANA) was 92.6%, the concentration and mass detection limit of NANA were 9.6 mumol/L and 39 fmol respectively. This method was used for the determination of NANA level in the serum of 11 lung cancer patients and 30 normal adults. The results showed that the average concentration of NANA in the serum of patients was much higher than that of normal adults with P < 0.001. The results were also compared with those obtained by the traditional colorimetric method, with good linear relationship of r = 0.983 at n = 10. It is concluded that the method described in this paper is simple and sensitive, and is suitable for basic research and clinical applications to malignant tumors.

[Influence of organic modifier on the retention behaviour in soil leaching column chromatography]

The relationship between capacity factors (k') of 55 nonionic compounds and broad methanol volume percentage (psi) of methanol-water eluent in soil leaching column chromatography (SLCC) was systematically investigated. The compounds consist of 11 chlorobenzenes, 14 alkylbenzenes, 22 polyphenyls and polycyclic aromatic hydrocarbons, and 8 pesticides. Reference soil was dry-packed into a stainless steel chromatographic column (10 mm i.d. x 100 mm) by a homemade pressurizing device, and isocratic methanolwater mixture with psi from 0.0 to 0.80 eluated through the column at a flow-rate of 1 mL.min-1. The column was thermostated at (25.0 +/- 0.1) degree C, and chromatographic peak was monitored by an online ultraviolet detector. The results show that both equations, log k' = log k'w + a psi + b psi 2(1) and log k' = log k'w - S psi (2), well fit the retention values. Equation (2) can be used practically due to few experimental data needed and simpler in formula. Explanation is also given for the existence of the carbon (or chlorine) number rule for two classes of homologous series (i.e. methylbenzenes, n-alkylbenzenes) and weak-polar chlorobenzenes in the SLCC process. The slope and intercept of the rule are also well correlated, and both decreases linearly with increasing eluent psi value.

[Chiral separation of naproxen and flurbiprofen by capillary electrophoresis]

The acidic chiral drugs naproxen and flurbiprofen were successfully separated into two enantiomers when beta-cyclodextrins (beta-CDs) were used as chiral selectors by capillary zone electrophoresis, under the conditions of 0.1 mol/L phosphate buffer with pH 4.92. The comparison of four CDs, namely beta-CD, DM-beta-CD, HP-beta-CD and TM-beta-CD for chiral separation was made. Naproxen can be separated by either beta-CD or its derivatives, while flurbiprofen can only be separated by TM-beta-CD among the CDs. The elution order of enantiomers of naproxen in different CDs was also studied, and the R form always eluted before S form when any of the four CDs was used as chiral selectors. The method of chiral separation for weak acidic compounds was also developed. It was proved that the optimum pH value for their chiral separation was about 5, close to its pKa value.

Postoperative myocardial infarction in a patient with perioperative ST-depression--a case report

Often we ignore electrocardiogram (EKG) evidence of ischemia and no adverse events occur. However, once in a while these ischemic episodes will turn into a full-blown myocardial infarction. Therefore, studying perioperative events which tilt the balance over to postoperative myocardial infarction (PMI) can enlighten our knowledge in postoperative myocardial infarction (MI) prevention. We present a case of ST depression in perioperative EKG evolving into postoperative MI. In this paper we attempt to explore various possibilities which could have altered this patient from her ischemic state into an infracted event.

Prognosis in presumptive hypoxic-ischemic coma in nonneurologic trauma

BACKGROUND

The neurologic outcome of comatose patients has a wide variation from complete reawakening to death. Methods of predicting the outcome of coma caused by either head injury or cardiac arrest have been the subject of much discussion in the literature. However, prediction of neurologic prognosis in comatose trauma patients without head injury has rarely been discussed. We reviewed our experience in treating patients with presumptive hypoxic-ischemic coma after trauma and tried to identify factors relating to their neurologic outcomes.

METHODS

Thirty-six patients with normal brain computed tomographic scans, who remained comatose 10 minutes after stabilization of their hemodynamic status, were studied. Serial motor response, verbal response, pupillary light reflex, presence of spontaneous breathing and seizure, and blood glucose level were recorded to evaluate their roles in predicting neurologic outcomes.

RESULTS

There were five deaths (mortality rate, 14%) and 11 patients (31%) with neurologic deficits. An absence of spontaneous breathing, a blood glucose level greater than 300 mg/dL during resuscitation, and a presence of seizure signified a poor prognosis. Initial neurologic evaluation at 10 minutes after stabilization of hemodynamic status was not accurate in predicting outcome. A motor response worse than withdrawal from painful stimuli at 24 hours after injury and an absence of pupillary light reflex at 48 hours after injury predicted a poor neurologic outcome, with a 100% accuracy rate.

CONCLUSION

Hypoxic-ischemic coma in patients sustaining major trauma yielded a significantly better survival and neurologic outcome than that induced by cardiac arrest or head injury. Decision-making in the first 24 hours after injury should not be affected by the patient's neurologic status at that time. A motor response worse than withdrawal at 24 hours after injury and an absence of pupillary light reflex at 48 hours after injury predicted a poor neurologic outcome.

Small bowel perforation: is urgent surgery necessary?

BACKGROUND

Controversies regarding how urgent bowel perforation should be diagnosed and treated exist in recent reports. The approach for early diagnosis is also debatable. The purposes of this study were to evaluate the relationship between treatment delay and outcome of small bowel perforation after blunt abdominal trauma and to determine the best assessment plan for the diagnosis of this injury.

METHODS

One hundred eleven consecutive patients with small bowel perforations caused by blunt abdominal trauma were retrospectively reviewed. The patients were divided into four groups according to the time interval between injury and surgery. Hospital stay, time to resume oral intake, and mortality and morbidity rates were compared between groups. Physical signs, laboratory and computed tomographic findings, and the results of diagnostic peritoneal lavage were analyzed to find the most sensitive and specific test for early diagnosis of small bowel perforation.

RESULTS

Delay in surgery for more than 24 hours did not significantly increase the mortality with modern method of treatment; however, complications increased dramatically. Hospital stay and time to resume oral intake increased significantly when surgery was delayed for more than 24 hours. Abdominal tenderness was a common finding, but it was not specific for bowel perforation. Only 40% of the computed tomographic scans were diagnostic for bowel perforations: 50% of them showed suggestive signs, and 10% were considered as negative. Persistence of abdominal signs indicated peritoneal lavage. By using cell count ratio in diagnostic peritoneal lavage and/or increased lavage amylase activity, presence of particulate matter and/or bacteria in the lavage fluid, all patients with intraperitoneal bowel perforation were diagnosed accurately before operation.

CONCLUSION

Small bowel perforation has low mortality and complication rates if it is treated earlier than 24 hours after injury. The principle of "rushing to the operation suite" for a stable blunt abdominal trauma patients without detailed systemic examination is not justified. The priority of treatment for the small bowel perforation should be lower than the limb-threatening injuries. Diagnostic peritoneal lavage provides high sensitivity and specificity rates for the diagnosis of small bowel perforation if a specially designed positive criterion is applied.

Anesthesia for ankylosing spondylitis patients undergoing transpedicle vertebrectomy

BACKGROUND

Ankylosing Spondylitis (AS) patients present specific challenges to the anesthesiologists. Airway management, central venous access, positioning, neuraxial monitoring and protection as well as management of massive blood loss may prove to be difficult. We retrospectively reviewed the anesthetic management of consecutive AS patients who underwent transpedicle vertebrectomy (TPV).

METHODS

To secure airway and administer anesthesia, we used awake fiberoptic endotracheal intubation. The central venous access was attempted through the infraclavicular approach. The positioning was made possible with modification of the operation table and padding. The neuraxial monitoring was done with both somatosensory evoked potentials (SSEPs) and the modified transcranial magnetic evoked potential (tcMMEP). The spinal cord protection was attempted with deliberate hypothermia. To prevent massive blood loss we did controlled hypotension, and autotransfusion.

RESULTS

Fiberoptic endotracheal intubation was done smoothly in all cases except two. In one of these two cases, endotracheal intubation was successful only after cricothyroidectomy and retrograde intubation. In the other case antegrade stiff catheter guided intubation was attempted to overcome the acute angulation cause by fixed cervical flexion. Central venous access through infraclavicular approach was agreeable except one case of pneumothorax. Massive rapid blood loss during vertebral osteotomy, occurred in one patient with fall of the mean blood pressure to 20 mmHg and ventricular tachycardia for 10 min, during which all the SSEPs and tcMMEP activities disappeared. The patient recovered without sequelae.

CONCLUSIONS

Although it is extremely challenging, with proper planning, anticipation of difficulties and meticulous work in airway management, central venous catheterization and positioning as well as prevention of neurological injury and massive bleeding, we successfully accomplished fine job of anesthesia for the AS patients presented for correction of severe kyphosis.

Retroperitoneal laparostomy: an effective treatment of extensive intractable retroperitoneal abscess after blunt duodenal trauma

BACKGROUND

Delay in surgical treatment and duodenal wound dehiscence are two major causes of extensive retroperitoneal abscess formation after blunt duodenal injury. This complication is traditionally treated with primary repair of the duodenal wound and drainage of the abscess through anterior laparotomy. Pyloric exclusion is sometimes added as an adjunctive procedure. The anterior approach, however, may result in inadequate drainage, and repeat surgery is sometimes needed. We reviewed our experiences and evaluated the effectiveness of retroperitoneal laparostomy for the treatment of retroperitoneal abscess with continuous soiling.

METHODS

There were 52 blunt duodenal injuries during a 7-year period. Eleven patients developed extensive retroperitoneal abscesses.

RESULTS

All 11 patients were treated with anterior laparotomy initially. Five patients recovered after this procedure. Six patients continued to have retroperitoneal abscesses and were under septic status. Two patients received another anterior drainage, and had recurrent abscesses later. Retroperitoneal laparostomy was performed for these six patients. After retroperitoneal laparostomy, daily wound care, and antibiotic treatment, all six patients recovered. Only two patients developed incisional hernia.

CONCLUSION

Retroperitoneal laparostomy is effective in treating extensive intractable retroperitoneal abscess after blunt duodenal injury. Patients with the complications of duodenal leak and extensive retroperitoneal abscess should be treated with pyloric exclusion and drainage through anterior laparotomy first. If the duodenal wound does not heal after pyloric exclusion and retroperitoneal abscess persists, retroperitoneal laparostomy should be performed without further attempt to repair the wound.

Dynorphin A enhances mitogen-induced proliferative response and interleukin-2 production of rat splenocytes

It has been well known that immune function is modulated by endogenous opioid peptides: beta-endorphin and enkephalins. However, the effect of dynorphin A on the immune function has not been well documented. In this study, we investigated dynorphin A in the regulation of mitogen-induced proliferation and and interleukin-2 (IL-2) production of rat splenocytes. The results showed that dynorphin A 1-13 as well as dynorphin A 1-17 enhanced concanavalin A-stimulated [(3)H] thymidine uptake 46-112% and IL-2 production in a dose-dependent fashion. These effects were reversed by naloxone and norBNI, a selective kappa-receptor antagonist. Dynorphin A reduced cyclic AMP contents in spenocytes in naloxone and norBNI reversible fashion. The data suggest that dynorphin A enhanced mitogen-stumulated lymphocyte proliferation and IL-2 production via kappa-opioid receptor and cAMP pathway.

Surgical treatment and outcome after delayed diagnosis of blunt duodenal injury

OBJECTIVE

To review our experience of 18 patients with duodenal injuries after blunt trauma, the diagnosis of which had been delayed for more than 24 hours.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Taiwan, R.O.C.

SUBJECTS

18 patients who presented with duodenal injuries between January 1986 and December 1995.

MAIN OUTCOME MEASURES

Morbidity and mortality.

RESULTS

The reasons for the delay were: injuries not found during the first operation (n = 6), patients had not sought medical help (n = 6), and injuries treated conservatively at local hospitals (n = 5). There was one delay in our department because the patient lost consciousness. 12 patients were treated by pyloric exclusion with no deaths and four complications (one duodenal fistula and 3 retroperitoneal abscesses). The other 6 had various operations including pancreaticoduodenectomy, jejunostomy, and gastrostomy, with six complications and one death, giving an overall mortality of 6% and morbidity of 50%. Three patients developed delayed extensive retroperitoneal abscesses and all three were treated successfully by laparostomy. 16 of the 18 patients required enteral feeding through a jejunostomy.

CONCLUSIONS

Though the complication rate was high, the use of pyloric exclusion and a feeding jejunostomy kept the mortality low. Enteral nutrition should be started early. Laparostomy is a good way to manage retroperitoneal abscesses. To avoid delay, patients at risk of duodenal injuries should be evaluated early by experienced trauma surgeons and any central retroperitoneal haematoma should be explored during the initial laparotomy.

Modified transcranial electromagnetic motor evoked potential obtained with train-of-four monitor for scoliosis surgery

BACKGROUND

To monitor the spinal cord with somatosensory evoked potential (SSEP) is an accepted adjunct in the surgical correction of spinal deformities, but it does not directly assess the motor function. The use of motor evoked potential (MEP) has thus been introduced in an effort to meet this important need.

METHODS

This preliminary report concerned 30 cases of scoliosis who underwent surgical correction under the surveillance of modified transcranial electromagnetic motor evoked potential (tcMMEP). Train-of four (TOF) stimulator output was connected to an electromagnetic stimulator. The rate of repetition and interval of stimulation were controlled by TOF stimulator. Electromyographic (EMG) signals were obtained from the abductor hallucis muscle of both feet and interpreted as MEP activity. Anesthesia was made possible by propofol as a basic agent and isoflurane as supplement. Analgesia was obtained with sufentanil and fentanyl and amnesia enhanced by midazolam. Atracurium mixed with vecuronium in a ratio of 4:1 by weight in possible lowest dose was given to provide adequate muscle relaxation yet without the molestation of rapid reversal upon the request of wake-up test by the surgeon. Deliberate hypothermia and controlled hypotension were also applied since they did not interfere with the tcMMEP signals.

RESULTS

Although no attempt was made to control the level of muscle relaxation at T1 more than 30%, tcMMEP signals could be obtainable during induction, at the time of surgical correction and at the end of the operation. TcMMEP onset latency was 27.32 +/- 0.45 msec on the left side and 27.27 +/- 0.54 msec on the right side. The amplitude was 3.52 +/- 1.97 mV on the left side and 4.05 +/- 1.22 mV on the right side.

CONCLUSIONS

The modified tcMMEP is so stable and convincing that research for similar modification is now undergoing with the other brand of TOF monitor by our team.

Pooling of contrast material on computed tomography mandates aggressive management of blunt hepatic injury

BACKGROUND

Nonoperative management of blunt hepatic injury is currently a widely accepted treatment modality. Computed tomography (CT) is an important imaging study both for diagnosis and follow-up of these patients. There is, however, no reliable predictor of failure of nonoperative treatment other than the ultimate development of hemodynamic instability. Previous reports mostly were based on the data obtained from low-speed dynamic incremental scanners. The purpose of this study is to evaluate the value of a high-speed helical scanner in predicting the outcome of patients managed nonoperatively.

METHODS

During a 30-month period, 194 patients with blunt hepatic injury were treated, 150 of them were hemodynamically stable after initial resuscitation and underwent abdominal CT examination. All CT scans were performed with the High Speed Advantage Scanner. The CT scans and medical records were reviewed.

RESULTS

Nonoperative management was successfully applied to all patients with grade I and II, 93% of grade III, 87% of grade IV, and 67% of grade V liver injuries. Twelve patients required liver-related celiotomy. Pooling of contrast material was detected on the CT scans of 8 patients. Six (75%) of these patients developed hemodynamic instability and required liver-related celiotomy later. Pooling of contrast material can be detected in 50% of the patients receiving liver-related celiotomy.

CONCLUSION

The presence of pooling of contrast material within the hepatic parenchyma indicates free extravasation of blood as a result of active bleeding. In patients with blunt hepatic injury, if this sign is detected, nonoperative treatment should be terminated and angiography or celiotomy undertaken promptly. With the increasing use of high-speed spiral CT scanner and improvement in scanning technique, pooling of contrast material may become a sensitive sign for active bleeding and may be used as a guide for the selection of treatment modality.

Cell count ratio: new criterion of diagnostic peritoneal lavage for detection of hollow organ perforation

OBJECTIVES

Diagnostic peritoneal lavage (DPL) had been widely used in evaluating patients with suspected intraperitoneal injuries due to its high sensitivity. If the positive criteria are strictly followed, however, the incidence of nontherapeutic laparotomies will be unacceptably high. This realization has become more important recently with the popularization of nonoperative treatment for blunt solid organ injuries. For these patients, the early diagnosis of an associated hollow organ perforation is mandatory.

METHODS

Three hundred and twenty patients undergoing DPL over an 18-month period were retrospectively reviewed to evaluate the usefulness of "cell count ratio" in diagnosing hollow organ perforation. The cell count ratio was defined as the ratio between white blood cell count and red blood cell count in the lavage fluid divided by the ratio of the same parameters in the peripheral blood.

RESULTS

Two hundred twelve patients were diagnosed as having a positive DPL according to the classic criteria. Forty-four patients (21%) had a cell count ratio of greater than or equal to 1. The diagnosis at laparotomy was small bowel perforation in 31 patients, colon perforation in eight patients, diaphragmatic hernia in one patient, pancreatic transection in two patients, and liver laceration in two patients. None of the patients with a cell count ratio of less than I sustained hollow organ perforation. The average interval from injury to DPL was 5 hours, with the shortest being 1.5 hours.

CONCLUSION

A cell count ratio of greater than or equal to 1 predicted hollow organ perforation with a specificity of 97% and a sensitivity of 100%. The selective use of the cell count ratio has improved the probability of early diagnosis of bowel perforation without increasing the cost of care. Nonoperative management can be applied more confidently to those patients sustaining a blunt solid viscus injury of the abdomen if the cell count ratio is low. We conclude that the cell count ratio of DPL effluent is a very sensitive and specific indicator of hollow organ perforation. In the treatment of blunt abdominal injuries, if the cell count ratio is positive, nonoperative treatment should be abandoned and a laparotomy undertaken.

The maternal and fetal effects of the addition of sufentanil to 0.5% spinal bupivacaine for cesarean delivery

BACKGROUND

Opioid added to local anesthetic for spinal anesthesia was first introduced into clinical practice in 1979 with intrathecal morphine as a forerunner. As morphine is water soluble and has prolonged action, late respiratory depression following spinal anesthesia is not infrequent and is the most serious complication that causes our concern. Sufentanil which is more hydrophobic than morphine also with shorter duration of action and quicker onset when injected into the subarchnoid space could be more effective and a safer drug as an adjuvant to local anesthetic in spinal anesthesia.

METHODS

Forty-one parturients who had given consent to spinal anesthesia for Cesarean delivery, were anesthetized with 12.5 mg of 0.5% bupivacaine alone or in combination with 10 micrograms sufentanil in a randomized double blind manner. They were assigned either to C group (Control group) in which nothing is added to the local anesthetic and S group (Study group) in which sufentanil was added to the local anesthetic.

RESULTS

Perioperatively, hypotension occurred more in S group (17 against 11) but chest discomfort was less (3 against 7). Within 3 h after anesthesia 3 out of 19 parturients in S group requested analgesics but almost all parturients in C group did so.

CONCLUSIONS

The addition of intrathecal sufentanil to 0.5% bupivacaine for spinal anesthesia improved perioperative discomfort and significantly reduced the demand of post-operative analgesia but on the other hands, it tended to increase perioperative hypotension and cause mild pruritus.

Controlled reopen suture technique for pyloric exclusion

BACKGROUND

Pyloric exclusion had been widely used in the management of complicated duodenal injuries. The original concept of pyloric exclusion was that this technique would temporarily exclude the pylorus during the healing phase, but would subsequently allow resumption of normal gastrointestinal tract transit through the duodenum. The best method for pyloric exclusion has not been well established. Controversies exist regarding the need for a gastrojejunostomy and vagotomy as part of the procedure. None of these combinations can fulfill the original concept of pyloric exclusion and avoid late complications.

METHODS

We developed a controlled reopen suture technique for pyloric exclusion. This technique was applied to nine patients (group II) with a complicated blunt duodenal injury over the past 5 years. The clinical courses and outcomes of these patients were compared with an eight-patient comparison group treated by pyloric exclusion and gastrojejunostomy (group I) over the same time period.

RESULTS

All 17 patients survived. There were one early (duodenal wound leakage) and two late complications (marginal ulcers) in the group I patients. No delayed complications were found in the group II patients. The average hospital stay was about the same in both groups.

CONCLUSION

The controlled reopen suture technique is a quick and simple procedure. In the treatment of a complicated blunt duodenal injury, if repair of the duodenal wound will not compromise the lumen, gastrojejunostomy and vagotomy can be omitted when using this technique. This technique offers the best combination of limited surgery in the severely injured patient, effective exclusion of the duodenum until after the healing has occurred, and allowance for the resumption of normal gastrointestinal tract transit through the duodenum. The late complications of gastrojejunostomy can also be avoided.

Traumatic thoracic aortic injury caused by a sharp edge of left fractured rib on body position change: case report

Aortic injury caused by penetration of a fractured rib is very rare. We present a patient with aortic injury demonstrated using serial imaging studies. A 66-year-old woman fell from a ladder and sustained multiple left-side rib fractures. There was a small left hemothorax and widened mediastinum on the initial chest roentgenogram in the emergency department. Chest computed tomography (CT) revealed a posterior segmental fracture of the sixth rib on the left side with a sharp edge penetrating into the posterior aspect of the thoracic aorta. It was initially missed. More than 1000 cc of fresh blood suddenly gushed out of the chest tube 7 hours after the traumatic event. After resuscitation, an aortogram was performed which showed blood extravasation from the thoracic aorta at the rib fracture site. Unfortunately, surgical intervention was delayed and she died. Early detection and early surgical intervention are necessary in patients with a widened mediastinum and positive results on imaging studies.

Periaortic hematoma on helical CT of the chest: a criterion for predicting blunt traumatic aortic rupture

OBJECTIVE

The purpose of this study was to evaluate the accuracy of helical CT of the chest for predicting blunt traumatic aortic ruptures when periaortic hematoma is used as a positive criterion.

CONCLUSION

We recommend the use of periaortic hematoma as a criterion for predicting traumatic aortic ruptures on CT because this criterion is sensitive and can reduce the false-positive rate of CT interpretations.

Selective application of laparoscopy and fibrin glue in the failure of nonoperative management of blunt hepatic trauma

BACKGROUND

Most blunt hepatic trauma patients can be managed nonoperatively. The current failure rate in adult blunt hepatic trauma is reportedly 0 to 19%. We wished to evaluate the applicability of laparoscopy and fibrin glue as a minimally invasive alternative to laparotomy in these unsuccessfully nonoperative cases.

METHODS

All adult patients with blunt hepatic trauma managed nonoperatively at Linkou, Chang Gung Memorial Hospital Medical Center, Taipei, Taiwan, over a 2-year period from July 1, 1994, to June 30, 1996, were eligible for the study. A laparoscopic examination was performed on those who failed conservative care before undertaking an exploratory laparotomy. Fibrin glue was sprayed over the wound surface if ongoing hemorrhage was evident from any liver laceration. The clinical data, operative and laparoscopic findings, operative methods, and outcomes of these patients were studied.

RESULTS

Of the 61 patients, 55 patients were successfully treated without operation. Of the six failures (10%) all were liver related. After the introduction of laparoscopy, the nontherapeutic laparotomy rate would have decreased from 100% (6 of 6) to 50% (3 of 6), and with the adjunctive use of fibrin glue, the laparotomy rate went down to 0% (0 of 6). There were no deaths among the six patients receiving laparoscopy and fibrin glues; and only one developed a liver abscess, for a morbidity rate of 17% (1 of 6).

CONCLUSIONS

The selective use of laparoscopy and fibrin glue can effectively reduce the nontherapeutic laparotomy rate among blunt hepatic trauma patients who fail nonoperative management.

Method for reduction of inhibition in a Mycobacterium tuberculosis-specific ligase chain reaction DNA amplification assay

The present study describes the identification of inhibitors of a Mycobacterium tuberculosis-specific gap ligase chain reaction (LCR) DNA amplification assay as well as a method for their removal. A major contributor to inhibition was deduced to be a calcium phosphate precipitate, CaHPO4. The precipitate forms during N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) decontamination, digestion, and concentration of respiratory specimens. The solubility product of CaHPO4 precipitate at pH 7.8, the pH at which gap LCR is optimized, indicates that the precipitate releases an amount of phosphate ions sufficient to inhibit amplification. A method for removal of the precipitate was identified. The precipitate is dissociated by exposing it to a mildly acidic (pH 4.1) buffer during the first of two centrifugation steps; the inhibitory phosphate ions are removed by the centrifugation steps. When 100 NALC-NaOH respiratory sediments were tested by gap LCR, none of the sediments were inhibitory when the acidic buffer was used while 24 samples were inhibitory when TE buffer, pH 7.8, was used. In another study, when the acidic buffer wash was applied to 1,440 NALC-NaOH respiratory sediments, only 10 sediments were found to be inhibitory. None of the inhibited sediments were culture positive for M. tuberculosis. This work demonstrates that when inhibition mechanisms are identified, relatively simple protocols can be used to obtain low inhibition rates and to allow the use of larger volume equivalents in amplification reactions.

Malakoplakia of the mesocolon with gastric serosa invasion: a case report and review of the literature

Malakoplakia is a rare, granulomatous, inflammatory disease. The clinical presentation and radiological appearance of the malakoplakia mimics a malignant tumor. In this article we describe a case of the malakoplakia of the mesocolon with invasion into the serosa of the stomach. The frozen section report considered the lesion to be a malignancy. The definitive diagnosis depended on microscopic detection of Michaelis-Gutmann bodies by electronic microscope. We review the current literature about the malakoplakia of gastrointestinal tract, and focus on the pathogenesis, clinical manifestation, diagnosis and treatment.

A conformational switch in nuclear hormone receptors is involved in coupling hormone binding to corepressor release

Nuclear hormone receptors are ligand-regulated transcription factors that modulate gene expression in response to small, hydrophobic hormones, such as retinoic acid and thyroid hormone. The thyroid hormone and retinoic acid receptors typically repress transcription in the absence of hormone and activate it in the presence of hormone. Transcriptional repression is mediated, in part, through the ability of these receptors to physically associate with ancillary polypeptides called corepressors. We wished to understand the mechanism by which corepressors are recruited to unliganded nuclear hormone receptors and are released on the binding of hormone. We report here that an alpha-helical domain located at the thyroid hormone receptor C terminus appears to undergo a hormone-induced conformational change required for release of corepressor and that amino acid substitutions that abrogate this conformational change can impair or prevent corepressor release. In contrast, retinoid X receptors appear neither to undergo an equivalent conformational alteration in their C termini nor to release corepressor in response to cognate hormone, consistent with the distinct transcriptional regulatory properties displayed by this class of receptors.

Plasticity of tetramer formation by retinoid X receptors. An alternative paradigm for DNA recognition

Retinoid X receptors (RXRs) are transcription factors that traditionally have been thought to bind DNA as protein dimers. Recently, however, it has been recognized that RXRs can also bind to DNA as protein tetramers. Receptor tetramers form cooperatively on response elements containing suitably reiterated half-sites, and play an important role in determining the specificity of DNA recognition by different nuclear receptors. We report here that RXR tetramers exhibit significant functional plasticity, and form on response elements possessing diverse half-site orientations and spacings. This ability of RXRs to form tetramers and related oligomers appears to contribute to the synergistic transcriptional activation observed when multiple, spatially separated response elements are introduced into a single promoter. Oligomerization may therefore be a common paradigm for DNA recognition and combinatorial regulation by several different classes of transcription factors.