Influences of Intestinal Ligation on Bacterial Translocation and Inflammatory Response in Rats with Hemorrhagic Shock: Implications for Damage Control Surgery

A Novel Method of Damage Control for Multiple Discontinuous Intestinal Injuries with Hemorrhagic Shock: A Controlled Experiment

Aim: In this study, we examined the effects of branched silicon tube (BST) and temporary closed circle (TCC) in a Beagle dog model of multiple transection of small intestine and discontinuities suspected intestinal necrosis with hemorrhagic shock. Materials and Methods: Ten male Beagle dogs were randomly divided into two groups. Hemorrhagic shock was induced by bleeding. Intestine was severed. Suspected intestinal necrotic model by ligating the mesenteric vessels was established, with a small tertiary mesenteric vessel reserved. Fracted intestines were ligated (IL group, n = 5) or reconnected with BST (IR group, n = 5). The abdominal cavity was temporarily closed with TCC. Definitive surgery was conducted after 24 h. Results: There was no statistical difference between two groups in the weight of dogs, their blood loss, fluid resuscitation, operation time of early emergency treatment (EET). After definitive surgery, all dogs in IR group and 3 dogs in IL groups were alive. 18 (90%) suspicious necrotic intestinal segments in IL group became necrotic, but 20 (80%) segments in IR group didn't develop obvious changes (p < 0.01). From 2 h after EET, the endotoxin concentration in IL group was significantly higher than that in IR group (133.87 ± 43.73 vs. 56.31 ± 24.70 pg/ml, p < 0.01). Microscopic examination revealed that much more severe damage occurred in the suspicious necrotic intestinal segments in IL group. Conclusion: Both reconnecting intestine with BST and temporary abdominal closure with TCC are viable methods of damage control for multiple discontinuous intestinal injuries.

A novel method for multiple bowel injuries: a pilot canine experiment

Background

Intestinal ligation is the cornerstone for damage control in abdominal emergency, yet it may lead to bowel ischemia. Although intestinal ligation avoids further peritoneal cavity pollution, it may lead to an increased pressure within the bowel segments and rapid bacterial translocation. In this study, we showed that severed intestine could be readily reconnected by using silicon tubes and be secured by using rubber bands in a canine model.

Methods

Adult Beagle dogs, subject to multiple intestinal transections and hemorrhagic shock by exsanguination, randomly received conventional ligation vs. silicon tubes reconnecting (n = 5 per group). Intestinal transections were carried out under general anesthesia after 24-h fasting. The abdomen was opened with a midline incision. The small intestine was severed at 50, 100, and 150 cm below the Treitz ligament. Hemorrhagic shock was established by streaming blood from the left carotid artery until the mean arterial pressure reached 40 mmHg in 20 min. Fluid resuscitation and surgery began 30 min after the establishment of hemorrhagic shock. Severed intestines were ligated or connected with silicon tubes. Definitive repair was conducted in subjects surviving for at least 48 h.

Results

Operation time was comparable between the two groups (39.6 ± 8.9 vs. 36.6 ± 7.8 min in ligation and reconnecting groups, respectively; p = 0.56). The time spent in managing each resection was also comparable (4.6 ± 1.1 vs. 3.8 ± 0.84 min; p = 0.24). Blood loss (341.2 ± 28.6 vs. 333.8 ± 34.6 ml; p = 0.48), and fluid resuscitation within the first 24 h (1676 ± 200.6 vs. 1594 ± 156.5 ml; p = 0.46) were similar. One subject in the ligation group was sacrificed at 36-h due to severe vomiting that led to aspiration. Four remaining dogs in the ligation group received definitive surgery, but two out of four had to be sacrificed at 24-h after definitive repair due to imminent death. All five dogs in the reconnecting group survived for at least a week. Radiographic examination confirmed the integrity of the GI tract in the reconnecting group. In both groups, plasma endotoxin concentration increased after damage control surgery, but the increase was much more pronounced in the ligation group. Microscopic examination of the involved segment of the intestine revealed much more severe pathology in the ligation group.

Conclusion

The current study showed that the reconnecting resected intestine by using silicon tubes is feasible under emergency. Such a method could decrease short-term mortality and minimize endotoxin translocation.

The role of the sensor kinase, QseC, an adrenergic receptor of Escherichia coli, in bacterial translocation during hemorrhagic shock

BACKGROUND

Hemorrhagic shock results in ileal mucosa damage and intestinal bacterial translocation. Additionally, during hemorrhagic shock, norepinephrine levels increase. Past research has shown that the QseC sensor kinase of Escherichia coli modulates the quorum-sensing response to epinephrine and norepinephrine. Therefore, the aim of our study was to examine whether the absence of the ability of E. coli to sense epinephrine/norepinephrine would attenuate the bacterial translocation to extraintestinal organs in a rat model of hemorrhagic shock.

METHODS

An E. coli MC1000 qseC mutant was constructed, and E. coli MC1000 and MC1000ΔqseC with streptomycin resistance were used to track bacterial translocation after gavage in rats. A rat model of nonlethal hemorrhagic shock was used. The rats were divided into six groups: controls (SS), rats that received a sham shock and MC1000 (M-SS), rats that received a sham shock and MC1000ΔqseC (Δ-SS), rats that received a hemorrhagic shock alone (HS), rats that received a hemorrhagic shock and MC1000 (M-HS), and rats that received a hemorrhagic shock and MC1000ΔqseC (Δ-HS).

RESULTS

We found the incidence of bacterial translocation in the M-HS rats was higher than in the Δ-HS rats. The observed effects seem to be largely dependent on the inability to sense epinephrine/norepinephrine and the decreased motility of E. coli MC1000ΔqseC.

CONCLUSION

Therefore, a role for E. coli sensing epinephrine/norepinephrine in the pathophysiology of bacterial translocation following hemorrhagic shock is proposed. The demonstration of such an effect would suggest a new mechanism for the development of shock-induced sepsis.

The Effect of Curcumin on an Animal Intestinal Ischemia/Reperfusion Model for Bacterial Translocation and Inflammatory Response

Ischemia/reperfusion (IR) injury of the intestine is a major problem in abdominal pathological condition and is associated with a high morbidity and mortality. The purpose of the study is to investigate the effects of curcumin on the bacterial translocation incidence and inflammatory response in rats submitted to bowel ischemia reperfusion injury. Thirty-two Wistar albino rats with a weight of 200 to 250 g were used in the study. They were randomly divided into 3 groups (n = 10 for each group): sham only operated group(group I); IR group (group II); and IR + curcumin treatment group (group III). Curcumin (curcumin from Curcuma longa) 20 mg/kg/day was given orally to the curcumin group. All animals were given 109 E. Coli by orogastric intubation 12 hours before sampling. Seventy-two hours after the first operation, mesenteric lymph node and blood samples were obtained and cultured. Blood samples of 2 mL were obtained for a polymerase chain reaction study. A piece of terminal ileum was also sampled for histopathologic examination. Mesenteric lymph node and blood cultures of all control animals were positive for microbiological growth, and polymerase chain reaction results were positive in seven of the eight rats. Histopathologically, edema, vasodilatation and inflammatory cell infiltration were found to be less in the other groups in comparison to the control group. Curcumin reduced bacterial translocation in blood, hepatocellular damage, and plasma cytokine levels. Curcumin reduced the incidence of bacterial translocation in intestinal I/R. rats. These results suggest that Curcumin would be clinically useful in the treatment of intestinal I/R injury.

Intraintestinal drainage as a damage control surgery adjunct in a hypothermic traumatic shock swine model with multiple bowel perforations

BACKGROUND

Temporary bowel ligation (TL) has been proposed to prevent contamination as a damage control procedure in multiple bowel perforations. However, bacteria translocation and intestinal ischemia may develop in a prolonged duration. We here hypothesized that intraintestinal drainage combined with temporary ligation (D-TL) would decrease intestinal injury and improve survivals in a gunshot multiple bowel perforation swine model in the setting of a damage control surgery.

MATERIALS AND METHODS

The abdomen was shot one time with an experimental modified gun whereas pigs were hemorrhaged to a mean arterial pressure of 40 mm Hg and maintained in shock for 40 min. Cold lactated Ringer solution was gradually infused to induce hypothermia. Animals were randomized to primary anastomosis, TL and intraintestinal D-TL groups (n = 8). Animals were resuscitated for 12 h with the shed blood and lactated Ringer solution. Delayed anastomosis was performed in TL and D-TL animals after resuscitation. Surviving animals were humanely killed 24 h after operation. Systemic hemodynamic parameters were recorded and blood samples were obtained for biochemical assays. Intra-abdominal pressure, portal vein and peripheral vein bacterial cultures, small intestine hematoxylin-eosin staining, and transmission electron microscopy examination were performed at 0, 2, 6, 12, and 24 h after the surgery.

RESULTS

All animals suffered extreme physiologic conditions as follows: hypothermia, severe acidosis, hypotension, and depressed cardiac output. Compared with the primary anastomosis and TL group, D-TL animals required less resuscitation fluid, suffered a lower intra-abdominal hypertension and bacterial translocation, normalized lactate levels faster, had lower serum creatine kinase, aspartate aminotransferase levels and tissue TNF-α level, and nuclear factor-kB activations and thus had greater early survival.

CONCLUSIONS

Compared with primary intestinal anastomosis and TL, rapid bowel ligation combined with intraintestinal drainage as a damage control adjunct improved survivals in a multiple bowel perforation swine model in the setting of damage control surgery.

Limited fluid resuscitation attenuates lung and intestine injury caused by hemorrhagic shock in rats

BACKGROUND AND OBJECTIVE

Different volume fluid resuscitations were closely associated with different cytokine responses, which could influence shock-induced lung and intestinal destruction. The aim of the study is to compare the effects of limited and traditional resuscitation on the levels of inflammatory response and lung and intestinal injury of hemorrhagic shock (HS) rats.

METHOD

Sprague-Dawley male rats were subjected to a blood pressure-controlled hemorrhage group following three kinds of resuscitation using lactated Ringer's (LR) solution (45, 30, 15 ml/kg·hr, respectively) and unresuscitation group. Then six rats of each group were sacrificed at 24, 48, and 72 hr, respectively.

RESULTS

The levels of plasma TNF-α, the plasma lactic acid, the intestinal permeability, and the ratio of wet weight to dry weight of lung and intestinal were lower in the group of 15 ml/kg·hr than other groups (p < .05). The lung and intestinal injury were more severe in group 45 ml/kg·hr than other groups in 24, 48, and 72 hr (p < .05).

CONCLUSION

Comparing with conventional fluid resuscitation, limited fluid resuscitation (LFR) could not only decrease the levels of lactic acid and pro-inflammatory factors but also attenuate the intestinal and lung injury.

Two-day fasting prior to intestinal ischemia-reperfusion injury on bacterial translocation in rats

PURPOSE

The aim of this study is to verify the effect of two-day fasting prior to intestinal ischemia-reperfusion (I/R) injury on bacterial translocation (BT).

MATERIALS AND METHODS

Mail Sprague-Dawley rats were divided into four groups: group 1, control rats that underwent sham operation only; group 2, rats fasted for two days prior to sham operation; group 3, rats that underwent occlusion of mesenteric vessels for 30 min followed by reperfusion for 4 hr; and group 4, rats fasted for two days prior to the same intestinal I/R injury as in group 3. In all groups, E. coli labeled with (99m)Tc were inoculated into the terminal ileum. Two hr after inoculation of E. coli, the rats were killed. A segment of ileum was obtained for histological examination and samples of mesenteric lymph nodes (MLNs), liver, lung, blood, and spleen were obtained for radioactivity determination.

RESULTS

There were no significant differences in the intestinal mucosa and radioactivity of all samples between groups 1 and 2. Group 3 showed significantly shorter mucosa and villi, and higher radioactivity of samples, except for MLNs, compared to group 1. Group 4 showed similar mucosa and villi, but significantly higher radioactivity of samples, except for MLNs, compared to group 3.

CONCLUSION

Two-day fasting without I/R injury does not cause mucosal change and BT, but in cases following intestinal I/R injury, two-day fasting increases the susceptibility of BT to systemic organs in rats.

Temporary rapid bowel ligation as a damage control adjunct improves survival in a hypothermic traumatic shock swine model with multiple bowel perforations

BACKGROUND

Primary intestinal anastomosis is not the right choice for multiple bowel perforations under hemodynamically stable conditions. Our group has employed temporary rapid bowel ligation as a damage control procedure in a hypothermic traumatic shock swine model with multiple bowel perforations and hypothesized that damage control treatment would improve survival in the setting of a damage control surgery.

MATERIALS AND METHODS

The abdomen was shot one time with an experimental modified gun while pigs were hemorrhaged to a mean arterial pressure of 40 mm Hg and maintained in shock for 40 min. Cold lactated Ringer solution was gradually infused to induce hypothermia. Animals were randomized to control (no resuscitation), primary anastomosis (PA), or temporary rapid bowel ligation (damage control group, DC). Animals were resuscitated for 12 h with the shed blood and lactated Ringer solution. Delayed anastomosis was performed in DC animals after resuscitation. Surviving animals were humanely killed 24 h after operation. Systemic hemodynamic parameters were recorded and blood samples were obtained for biochemical assays. The lung and ileum was harvested at the end of the experiment for pathologic evaluation and test of wet/dry weight ratio, TNF-α level, and nuclear factor-κB activations.

RESULTS

All animals suffered extreme physiologic conditions: hypothermia, severe acidosis, hypotension, and depressed cardiac output. Control animals suffered 100% mortality. Compared with the PA group, DC animals required less resuscitation fluid, normalized lactate levels faster, had lower serum creatine kinase, aspartate amino transferase levels and tissue TNF-α level and nuclear factor-κB activations, suffered less severe histopathology, had greater early survival.

CONCLUSIONS

Multiple bowel perforations under hemodynamically stable conditions seem better managed with DC than with PA. Temporary rapid bowel ligation as a damage control adjunct is important to rapid control of multiple bowel perforations instead of a prolonged operative time.

Effect of melatonin and misoprostol on bacterial translocation in portal hypertensive rats

BACKGROUND AND AIM

Portal hypertension is the main complication of cirrhosis and it is responsible for its most common complications. Bacterial translocation increases the morbidity and mortality rates in patients with portal hypertension. We aimed to investigate the effects of melatonin and misoprostol on bacterial translocation induced by portal hypertension.

METHODS

We established four groups, each containing eight rats. Except for the control and sham groups, the animals in the other groups (treatment groups) received misoprostol or melatonin for 3 days after the first operation. In the sham group, a laparotomy was carried out and only the portal vein was dissected. Calibrated portal vein ligation was carried out in the other groups. All animals were given 10(10) Escherichia coli by orogastric intubation 12 h before sampling. Seventy-two hours after the first operation, mesenteric lymph node and blood samples were obtained and cultured. Two cc blood samples were obtained for a polymerase chain reaction study. A piece of terminal ileum was also sampled for histopathologic examination.

RESULTS

Mesenteric lymph node and blood cultures of all control animals were positive for microbiological growth, and polymerase chain reaction results were positive in seven of the eight rats. Histopathologically, edema, vasodilatation and inflammatory cell infiltration were found to be less in the other groups in comparison to the control group. The incidence of bacterial translocation was decreased in all treatment groups as compared to the control group.

CONCLUSIONS

In this study, bacterial translocation occurred in portal hypertension. Melatonin and misoprostol reduced the incidence of bacterial translocation in portal hypertensive rats.

The role of toll-like receptor-4 in the development of multi-organ failure following traumatic haemorrhagic shock and resuscitation

Haemorrhagic shock and resuscitation (HS/R) following major trauma results in a global ischaemia and reperfusion injury that may lead to multiple organ dysfunction syndrome (MODS). Systemic activation of the immune system is fundamental to the development of MODS in this context, and shares many features in common with the systemic inflammatory response syndrome (SIRS) that complicates sepsis. An important advancement in the understanding of the innate response to infection involved the identification of mammalian toll-like receptors (TLRs) expressed on cells of the immune system. Ten TLR homologues have been identified in humans and toll-like receptor-4 (TLR4) has been studied most intensively. Initially found to recognise bacterial lipopolysaccharide (LPS), it has also recently been discovered that TLR4 is capable of activation by endogenous 'danger signal' molecules released following cellular injury; this has since implicated TLR4 in several non-infectious pathophysiologic processes, including HS/R. The exact events leading to multi-organ dysfunction following HS/R have not yet been clearly defined, although TLR4 is believed to play a central role as has been shown to be expressed at sites including the liver, lungs and myocardium following HS/R. Multi-organ dysfunction syndrome remains an important cause of morbidity and mortality in trauma patients, and current therapy is based on supportive care. Understanding the pathophysiology of HS/R will allow for the development of targeted therapeutic strategies aimed at minimising organ dysfunction and improving patient outcomes following traumatic haemorrhage. A review of the pathogenesis of haemorrhagic shock is presented, and the complex, yet critical role of TLR4 as both a key mediator and therapeutic target is discussed.