[Who is responsible for the removal of inferior vena cava filters?]

The fact that many inferior vena cava filters (IVCF) in trauma patients are not being removed has been described numerous times in the literature, but nobody really gives a reason why. This case presents a young patient who prophylactically received an optional IVCF after sustaining severe multitrauma. He had a failed retrieval 8 weeks post insertion and consequently was lost to follow-up before a second removal attempt was performed. Institutions inserting IVCF should establish guidelines for following up patients receiving prophylactic IVCF.

[Vena cava filters in trauma patients]

BACKGROUND

The introduction of removable inferior vena cava filters (IVCF) has created new options for the prevention of pulmonary embolisms in surgical trauma patients. We have observed increasing use in trauma patients.

PATIENTS AND METHODS

A retrospective analysis was carried out of 49 trauma patients out of 85 who received IVCFs at our level 1 trauma centre in 2008.

RESULTS

The indications for IVCF placement were multiple trauma in 33 patients, severe head injury in 13 and spinal injury in 3 patients. Of the patients 34 underwent successful removal, 11 (22%) patients had had no retrieval attempt by December 2009 and attempts at removal were unsuccessful in 3 patients. The mean age of the patients was 33.3 years.

CONCLUSION

In 2008 the vast majority of IVCFs were inserted for prophylaxis in trauma patients. To increase the number of retrieved IVCFs, responsibility for the removal should be clarified in every hospital. The indications, advantages, safety and also the design of IVCFs are still under debate. A randomized controlled trial is needed to determine the appropriate use and indications for this potentially useful device in trauma patients.

Apoptosis induction and reduced proliferation in human osteoblasts by rhBMP-2, -4 and -7

BACKGROUND

The role of bone morphogenetic proteins (BMPs) in bone healing has been demonstrated in numerous in vivo animal models. BMP-2, -4 and -7 have also been shown to stimulate the differentiation of human and animal stem cells into osteoblasts in vitro. There are, however, contradictory reports of BMPs causing apoptosis and inhibition of proliferation of osteoblastic cells. Therefore, a more complete understanding of the effects of BMP-2, -4 and -7 on human osteoblasts is required.

METHODS

Cells of the immortalised human fetal osteoblastic line hFOB 1.19 were exposed to recombinant human (rh) BMP-2, -4 and -7. In addition, primary human osteoblasts were exposed to rhBMP-7. Cell proliferation was measured using a colorimetric assay. Apoptotic cells were detected using the TUNEL assay.

RESULTS

The hFOB cells exposed in a dose-dependent manner to rhBMP-2, -4 and -7 had significantly lower rates of proliferation than non-treated cells, (p<0.01 for rhBMP-2, -4 and -7). The proliferation results for rhBMP-7 were replicated using primary human osteoblasts. Additionally, rhBMP-2, -4 and -7 induced a significantly higher rate of apoptosis in the hFOB cells, with a temporal and dose-dependent pattern (p<0.05), irrespective of the presence of serum growth factors.

CONCLUSIONS

Despite interest in the potential clinical application of BMPs to improve bone healing, further studies are necessary to determine their full biological function before they can be used confidently in humans.

[Whiplash injury--an update]

Whiplash injuries of the cervical spine are of paramount clinical and socioeconomic importance. To date, many problems in regard to diagnosis, classification, treatment and assessment have not been sufficiently solved. Diagnosis is often made subjectively and the ideal mode of treatment is still the subject of controversy. Scientific progress has lead to the development of a prognostic classification system, objective diagnostic tests, different treatment modalities and, perhaps most importantly, the production of more secure automobiles. Current scientific evidence of the assessment and treatment of whiplash injuries is only partially integrated into clinical routine, although modern strategies of combining medicamentous therapy with early physiotherapy has shown good results. Clear dignostic criteria and treatment guidelines would conquer the cost explosion associated with whiplash injuries largely evident in the Swiss-German population.

[Diagnosis and management of patients with mild traumatic brain injury--an update with recommendations and future perspectives]

Mild traumatic brain injury (TBI) is a reversible brain damage, without structural changes, which is caused by an external force. By definition, patients with mild TBI have a GCS of 13-15. It is an established risk factor for both morbidity and mortality. Prognosis is dependent on the primary damage incurred as well as secondary damage, for example, posttraumatic bleeding and oedema. Initial management should focus on the identification of patients at risk for serious intracranial pathologies. Investigations should be directed towards the severity of the injuries. Notably, the conventional X-ray is inadequate for the assessment of TBI. The following article discusses practical algorithms for the management of mild TBI and the indications for early use of CT.

Complete medulla/cervical spinal cord transection after atlanto-occipital dislocation: An extraordinary case

STUDY DESIGN

Case report.

SUMMARY OF BACKGROUND DATA

Traumatic atlanto-occipital dislocation (AOD) with a complete medulla/spinal cord transection is rare and believed to be fatal owing to the high level of the spinal cord injury. Clinical outcome is poor. Consequently, relatively few case reports of adult patients surviving this injury appear in the literature. OBJECTIVES AND RESULT: We present the case of a 20-year-old male, who sustained an AOD with a complete medulla/spinal cord transection in a motorcycle accident to discuss the possibility of long-term survival with this condition. The patient underwent occipito-cervical stabilization. With an Injury Severity Score of 75, by definition unsurvivable, the patient is 16 months after the injury, ventilated and fully dependent for all care.

CONCLUSION

Long-term survival following AOD with a complete medulla/spinal cord transection is possible if immediate resuscitation at the scene is available. Nevertheless, it remains questionable whether or not a patient with such a devastating injury and without any prospect of functional recovery should be kept alive under all circumstances.

Selective non-operative management of liver gunshot injuries

BACKGROUND

In contrast to non-surgical treatment of blunt liver trauma, non-operative management (NOM) of liver gunshot injuries (LGSIs) is not widely accepted. This prospective study evaluated an experience of NOM of gunshot wounds to the liver.

METHODS

All patients presenting with LGSIs who were haemodynamically stable with no evidence of peritonism underwent a protocol of NOM.

RESULTS

Thirty-three patients (mean age 25 (range 13-50) years) were enrolled over a 36-month period. Fourteen had grade III injuries according to the American Association for the Surgery of Trauma (AAST) classification, whereas 11 and eight patients sustained major (AAST IV/V) and minor (AAST I/II) injuries respectively. NOM was successful in 31 of 33 patients. Two patients required delayed laparotomy for indications unrelated to the hepatic trauma. One patient died from necrotizing fasciitis, which appeared unrelated to the liver injury.

CONCLUSION

This study demonstrated that, regardless of the grade of liver trauma, NOM is safe and effective in appropriately selected patients with LGSI treated in centres with suitable facilities.

Transdiaphragmatic pleural lavage in penetrating thoracoabdominal trauma

BACKGROUND

The purpose of this study was to determine the incidence of thoracic sepsis following a systematic thoracic cavity washout through the injured diaphragm in patients with penetrating thoracoabdominal trauma.

METHODS

Prospectively collected data on all patients presenting with penetrating thoracoabdominal trauma between July 1999 and July 2002 were analysed. Patients with peritoneal biliary-gastroenteric (BGE) contamination and a diaphragmatic laceration were managed by laparotomy and transdiaphragmatic thoracic lavage.

RESULTS

A total of 217 patients had penetrating thoracoabdominal injuries, of whom 110 had BGE contamination of the peritoneal cavity with spillage into the pleural cavity. The mean Injury Severity Score was 38.1. Gunshot and stab wounds occurred in 79 (71.8 per cent) and 31 (28.2 per cent) respectively. Contamination was from the stomach (55.4 per cent), large bowel (37.3 per cent), small bowel (29.1 per cent), gallbladder and bile ducts (9.1 per cent) and pancreas (6.4 per cent). Thoracic complications occurred in six patients (5.5 per cent): empyema in two, Escherichia coli-related pneumonia in three and pleuritis in one. There were no deaths.

CONCLUSION

A thoracic washout through the injured diaphragm in patients with penetrating thoracoabdominal trauma and BGE contamination was associated with a low rate of intrathoracic septic complications.

Factors affecting outcome in penetrating oesophageal trauma

Background

Penetrating oesophageal trauma is rare and the risk factors affecting outcome have not been clearly identified. Delayed management has been cited as a factor contributing to the high rates of morbidity and mortality, but evidence for this is lacking.

Methods

A retrospective study was undertaken of patients with penetrating oesophageal trauma presenting to a level I trauma centre over 8 years. Outcome was assessed in terms of mortality, morbidity (oesophageal and non-oesophageal), and length of hospital and intensive care unit (ICU) stays.

Results

Fifty-two patients with oesophageal injury who reached the operating theatre were included. The overall mortality rate was 6 per cent. Fifteen patients (29 per cent) developed oesophageal injury-related complications. Time from injury to management was the only important risk factor for the development of oesophageal complications (P = 0·001), but did not affect the length of ICU (P = 0·560) or hospital (P = 0·329) stay, incidence of non-oesophageal injury-related complications (P = 0·963) or death (P = 0·937). Patients with gunshot injuries spent longer in the ICU (P = 0·007) and the duration of hospital stay was longer for those with higher-grade oesophageal injuries (P = 0·025).

Conclusion

The risk of oesophageal injury-related complications was directly related to the interval between the trauma and definitive management of the oesophageal injury.

[Cost analysis of acute therapy of polytrauma patients]

The rising costs of the Swiss health care system are currently a source of discussion. Precise facts about the treatment costs in Switzerland are not available. The aim of this paper is to assess the price of the acute therapy of multiple trauma patients at the University Hospital of Zurich. We analysed the exact treatment costs of 16 patients with an average Injury Severity Score (ISS) of 33.9. All these cases had a private or a supplementary insurance coverage, were foreigners or were otherwise invoiced according to the so-called hospital tariff (Spitalleistungskatalog/SLK). We developed a concept to measure the expenditure not covered by the insurance of those with a basic insurance, who entail the largest percent of all hospitalized patients. The average amount invoiced was 128,135 Swiss Francs (31,266-310,358 CHF). After subtracting the profit, gained on cases charged according to the SLK, the remaining deficit per ordinary insured was 42-65% or 33,703-138,829 CHF The range of this amount depends on the insurance status of the afflicted person. If hospitals are required to work with a balanced budget, then these losses can no longer be neglected. New forms of invoicing multiply trauma patients must be found in Switzerland.

Diagnostic laparoscopy and diverting sigmoid loop colostomy in the management of civilian extraperitoneal rectal gunshot injuries

Background

This prospective study reviews the management of isolated civilian extraperitoneal rectal gunshot injuries using a protocol of diagnostic laparoscopy and abdominal wall trephine diverting loop colostomy, without laparotomy, distal rectal washout and presacral drainage.

Methods

Patients admitted to the trauma unit at Groote Schuur Hospital between January 2000 and December 2002 with a rectal injury were evaluated. A rectal injury was confirmed by digital rectal examination and proctosigmoidoscopy. Missile peritoneal violation was excluded by diagnostic laparoscopy. Normal laparoscopy was followed by creation of a diverting sigmoid loop colostomy through an abdominal wall trephine, without a laparotomy. No distal rectal washout or presacral drainage was performed.

Results

Of the 104 patients admitted with 106 rectal injuries, 20 (19·2 per cent) qualified for inclusion in the study. All had sustained low-velocity gunshot injuries of which 18 exhibited a transpelvic trajectory. Diagnostic laparoscopy was normal and a trephine diverting loop sigmoid colostomy was performed in all 20 patients. No pelvic sepsis occurred. Two patients developed rectocutaneous fistulas, both of which resolved without surgical treatment. Nineteen stomas have since been closed.

Conclusion

Low-velocity gunshot injuries isolated to the extraperitoneal rectum can be managed safely by laparoscopic exclusion of intraperitoneal missile penetration and diverting sigmoid loop colostomy, without laparotomy, distal rectal washout or presacral drainage

A soccer player with a sore toe: recognizing subungual osteochondromas

In contrast to usual osteochondromas, subungual osteochondromas may arise following trauma rather than from aberrations in bone development. The rarity of subungual osteochondromas frequently leads to misdiagnosis and undertreatment, especially as a sports injury. When patients have nail-bed bruising, x-rays can rule out or confirm bone involvement, as in our case of a 20-year-old soccer player who had increasing pain in his left great toe. Treatment consists of radical, anatomic resection of symptomatic osteochondromas with periosteal realignment to prevent recurrence. Functional outcome after resection is excellent.

Richter's hernia and Sir Frederick Treves: an original clinical experience, review, and historical overview

OBJECTIVE

To describe the clinical recognition, pathology, and management of Richter's hernia and to review the relevant literature of the past 400 years.

SUMMARY BACKGROUND DATA

The earliest known reported case of Richter's hernia occurred in 1598 and was described by Fabricius Hildanus. The first scientific description of this particular hernia was given by August Gottlob Richter in 1778, who presented it as "the small rupture." In 1887, Sir Frederick Treves gave an excellent overview on the topic and proposed the title "Richter's hernia." To his work-a cornerstone to modern understanding-hardly any new aspects can be added today. Since then, only occasional case reports or small series of retrospectively collected Richter's hernias have been published.

METHODS

The authors draw on their experience with 18 prospectively collected cases treated in the ICRC Lopiding Hospital for War Surgery in northern Kenya between February and December 1998 and review the relevant literature of the past 400 years.

RESULTS

The classic features of Richter's hernia were confirmed in all case studies of patients: only part of the circumference of the bowel is entrapped and strangulated in the hernial orifice. The involved segment may rapidly pass into gangrene, yet signs of intestinal obstruction are often absent. The death rate in the authors' collective was 17%.

CONCLUSION

Richter's hernia is a deceptive entity whose high death rate can be reduced by accurate diagnosis and early surgery. Considering the increasing incidence at laparoscope insertion sites, awareness of this special type of hernia with its misleading clinical appearance is important and of general interest.

Transfusion of washed and centrifuged shed RBCs during maxillofacial surgery affects cytokine concentrations

BACKGROUND

In patients undergoing elective maxillofacial surgery, hyperthermic reactions have been observed after the transfusion of autologous washed and centrifuged shed blood. It was the aim of this study to correlate the clinical features with changes in cytokine levels.

STUDY DESIGN AND METHODS

In 24 consecutive patients, TNFalpha, IL-1, and IL-6 levels were determined in washed and centrifuged shed RBCs (CS RBCs) and in the patient's serum before, as well as 15 and 120 minutes after transfusion. At the same time, blood was drawn for culture. Patients in whom whole blood was saved through the use of acute normovolemic hemodilution served as a control group (n = 6).

RESULTS

After the transfusion of CS RBCs, patients had not only elevated cytokine levels but also transient bacteremia involving the pathogens previously detected in CS RBCs. No rise in body temperature occurred.

CONCLUSION

In the light of these results, the use of CS RBCs in patients undergoing maxillofacial surgery should be restricted to those patients with no primary bacterial contamination.

Incidence of septic complications and multiple organ failure in severely injured patients is sex specific

BACKGROUND

Sexual hormones are potent regulators of various immune functions. Although androgens are immunosuppressive, estrogens protect against septic challenges in animal models. This study correlates sexual dimorphism with the incidence of posttraumatic complications in severely injured patients.

METHODS

From January of 1991 to February of 1996, 1,276 consecutive injured patients (Injury Severity Score [ISS] > or = 9 points) were studied. Males (n = 911) did not differ from females (n = 365) with regard to severity of injury (ISS) and injury pattern.

RESULTS

The incidence of posttraumatic sepsis (30.7%) and multiple organ dysfunction syndrome (29.6%) was significantly increased in severely injured males with ISS > or = 25 points in comparison to the equivalent group of females (sepsis, 17.0%; multiple organ dysfunction syndrome, 16.0%). No difference was found in patients with ISS < 25 points. Moreover, plasma levels of procalcitonin and interleukin-6 were elevated (p < 0.05) in severely injured males compared with females.

CONCLUSION

Sex influences posttraumatic morbidity in severely injured patients and supports the concept that females are immunologically better positioned toward a septic challenge.

Effect of naloxone on immune responses after hemorrhagic shock

OBJECTIVE

To determine whether naloxone administration after hemorrhagic shock has any beneficial or deleterious effect on immune responses.

BACKGROUND DATA

Hemorrhagic shock is known to produce immunodepression in both humans and experimental animals. Although studies suggest that endogenous opioids play a role in immune regulation in adverse circulatory conditions, it remains controversial whether these opioids exert beneficial or detrimental effects on immunity after shock. Moreover, little information is available concerning the effects of opioid receptor blockade using naloxone on cell-mediated immunity and endocrine responses after shock.

METHODS

Male C3H/HeN mice (25 g) were bled to and maintained at a mean arterial blood pressure of 35+/-5 mm Hg for 1 hr. The shed blood was then returned along with lactated Ringer's solution (two times the shed blood volume) to provide fluid resuscitation. The animals were randomized to receive either naloxone (1 mg/kg i.v.) or an equal volume of vehicle (saline) after the shed blood was returned, i.e., immediately before crystalloid resuscitation, and were killed at 2 hrs after resuscitation to obtain splenocytes, macrophages (peritoneal and splenic), and blood.

MEASUREMENTS AND MAIN RESULTS

Bioassays revealed significantly decreased release of all studied interleukins (interleukins-1, -2, -3, and -6) by peritoneal and splenic macrophages as well as significantly decreased splenocyte proliferative capacity after shock in vehicle-treated mice. Naloxone administration after hemorrhage resulted in either similar or even more decreased levels of interleukin release compared with vehicle-treated hemorrhaged mice. Significantly increased plasma corticosterone concentrations were observed in vehicle-treated animals compared with control animals. Naloxone administration did not have any significant effects on corticosterone plasma concentrations after hemorrhage.

CONCLUSIONS

These findings indicate the importance of the endogenous opioid system for the maintenance of immunity in adverse circulatory conditions, i.e., hemorrhage. Although additional studies involving different doses and/or times of naloxone administration may provide different results, the present findings raise the concern that naloxone administration in the traumatized host may have deleterious effects because it decreases peritoneal macrophage and splenic immune functions.

Minimal invasive treatment of proximal femur fractures with the long gamma nail: indication, technique, results

BACKGROUND

The surgical treatment of complex unstable proximal femur fractures from the trochanteric region to the middle shaft area is difficult and often highly invasive, especially in older patients with osteoporotic bones.

METHODS

In 1993, we began to treat all unstable proximal femur fractures from the trochanteric region to the middle third of the shaft with the long gamma nail (LGN) and allowed the patients immediate full weightbearing after surgery. Perioperative, postoperative, and follow-up data were analyzed.

RESULTS

During a 3-year period, we treated 37 patients with unstable proximal femur fractures with the LGN. Five of the patients had sustained pathological fractures, and four patients had sustained multiple trauma. The 37 operations were performed by 22 different surgeons with varying degrees of experience. The LGN implantations through maximal 40-mm skin incisions were performed in a mean skin-to-skin operation time of 125 minutes (range, 65-200 minutes) without any further complications. Thirty-one of the 37 patients were allowed immediate full weightbearing after the second postoperative day. The six patients who were not allowed full weightbearing were the ones who had multiple trauma (4) and those who were unable to walk before surgery (2). Three postoperative complications were as follows: one deep infection 4 months after surgery, one superficial infection 3 weeks after surgery, and one deep vein thrombosis 2 weeks after discharge. All three complications occurred in the group of patients who had sustained only one trauma. All traumatic fractures (n = 32) healed without any bone grafting, which means a union rate of 100%. Although immediate full weightbearing was allowed, there were no implant dislocations, implant failures, or other problems. The 30-day mortality was 0%. The follow-up examinations after a mean time of 6 months were very satisfying. All traumatic fractures were healed. The patients had symmetrical functional findings to the opposite side or before surgery, respectively, except for two patients with a leg shortening of 2 cm, two patients with an external malrotation of 10 degrees, and one patient with a hip extension deficit of 10 degrees after a pathological fracture.

CONCLUSION

The LGN is, after appropriate introduction and training, a safe and easy implant for the treatment of complex proximal femur fractures from the trochanteric region to the middle shaft area. The minimal invasive technique with low risks and minimal complications and the possibility of immediate full weightbearing sets a new standard, especially for older patients with osteoporotic bones.

Metoclopramide: a novel and safe immunomodulating agent for restoring the depressed macrophage immune function after hemorrhage

BACKGROUND AND OBJECTIVE

Recent studies have shown that administration of the anterior pituitary hormone, prolactin, after hemorrhage restored the depressed immune responses that are observed under those conditions. Because metoclopramide (MCP) is known to increase prolactin secretion and ultimately plasma prolactin levels, we attempted to determine whether administration of metoclopramide after hemorrhage produces any beneficial effects on the depressed splenocyte and peritoneal macrophage immune function after severe hemorrhage.

DESIGN, MATERIALS AND METHODS

Mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 60 minutes, then adequately resuscitated and segregated into two groups. One group received saline vehicle; animals in the other group were treated with metoclopramide (100 microg/100 g body weight, subcutaneously) before resuscitation. Two hours after saline or MCP injection, the animals were killed and macrophage as well as splenocyte cultures established. Plasma corticosterone levels were also measured.

RESULTS

The proliferative capacity of the splenocytes as well as their ability to release interleukin (IL)-2 and IL-3 in response to mitogen was markedly improved in animals that had hemorrhaged and that were treated with MCP compared with saline-injected mice. Moreover, the depressed splenic and peritoneal macrophage IL-1 and IL-6 release after hemorrhage was restored with MCP treatment. Furthermore, treatment with MCP prevented the increase in blood corticosterone levels seen after severe hemorrhage.

CONCLUSION

These results support the concept that the immunosuppression after hemorrhage may be mediated by hormones from the hypothalamic-pituitary-adrenal axis. Furthermore, MCP may be a useful adjuvant in the treatment of the trauma-hemorrhagic shock-induced immunosuppression.

Effects of prolactin and metoclopramide on macrophage cytokine gene expression in late sepsis

Previous studies indicate a profound suppression of tumour necrosis factor alpha (TNF-gamma), IL-1 beta and IL-6 release capacity by peritoneal macrophage (PM phi), splenic macrophage (SM phi) and Kupffer cells (KC) during late sepsis. Such a loss of functional capacity may reduce the animal's ability to ward off infection. Prolactin is known to enhance monocyte, T- and B-lymphocyte immune responses under normal conditions and has beneficial effects on cell-mediated immunity after haemorrhage. In the respect, the dopamine antagonist, metoclopramide, has been reported to increase circulating prolactin levels. Nonetheless, it remains unknown whether prolactin or metoclopramide have any salutary effect on macrophage (M phi) cytokine gene expression following sepsis. To study this, male C3H/HeN mice were subjected to sepsis and immediately thereafter were treated with prolactin (100 micrograms/25 g body weight, s.c.), metoclopramide (100 micrograms/100 g BW, s.c.) or given saline. PM phi, SM phi and KC (only SM phi and KC in metoclopramide-treated animals) were isolated at 24 h after sepsis. The monolayers were stimulated with or without LPS 10 micrograms/ml for 1 h in vitro. Total RNA was extracted and mRNA was detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). A significant depression of constitutive and inducible mRNA levels of IL-1 beta, IL-6 and TNF-alpha in all three M phi populations were observed, when compared with shams (with exception of KC IL-6 mRNA in unstimulated cells). Prolactin as well as metoclopramide treatment after the onset of sepsis caused significant elevation of constitutive and inducible cytokine gene expression in all macrophages examined. Thus, prolactin and metoclopramide enhance the depressed M phi gene expression and may be useful in improving cell-mediated immunity during sepsis.

Females in proestrus state maintain splenic immune functions and tolerate sepsis better than males

OBJECTIVES

To determine: a) whether the cell-mediated immune response during sepsis differs in females vs. males; and b) whether the survival rate in females is different than in males after a septic insult.

DESIGN

A prospective, randomized animal study.

SETTING

University research laboratory.

SUBJECTS

Male and female proestrus C3H/HeN mice.

INTERVENTIONS

After anesthesia, male and proestrus female mice underwent cecal ligation puncture to induce sepsis. The mice were killed at 24 hrs after the onset of sepsis.

MEASUREMENTS AND MAIN RESULTS

Splenocyte proliferation, as well as splenocyte interleukin (IL)-2 and IL-3 release, was determined by bioassay. In additional studies, survival rate after septic challenge was measured over 10 days. Splenocyte proliferative capacity and splenocyte IL-2 and IL-3 release were markedly decreased in male, but not in female, septic mice. Furthermore, the survival rate of septic female proestrus mice was significantly higher than in comparable male mice.

CONCLUSIONS

These results support the concept that the immune response of females differs from males, and that females are immunologically better positioned to meet the challenge of sepsis.

[Testing bone implants in cell lines and human osteoblasts]

Two different types of cell-line and fresh human osteoblasts, cultured from cancellous bone grafts from the iliac crest, were used for the study. Three different biomaterials were compared regarding biocompatibility: titanium, steel and hydroxyapatite. The cells were fibroblast cell line (3T3), "osteoblast-like" cell line (MC3T3-E1), and fresh human osteoblasts (HOB) which we cultured in our laboratory. 5 x 10(4) cells of each type were seeded on the three different bone implants. All experiments were performed in triplicate. Cell proliferation and alkaline phosphatase activity were determined 24 and 72 h after the cells were plated on the biomaterials. Human osteoblast growth was better on titanium than on steel and hydroxyapatite. The most remarkable observation was the continuously decreasing alkaline phosphatase activity (ALP) of "osteoblast-like" cells (MC3T3-E1) and human osteoblasts (HOB) on hydroxyapatite. In conclusion, our in vitro observations suggest that the best cell/material interactions were with human osteoblasts (HOB) and titanium.

Prolactin administration following hemorrhagic shock improves macrophage cytokine release capacity and decreases mortality from subsequent sepsis

Although prolactin is reported to counteract the immunosuppressive effects of glucocorticoids, cyclosporine, and morphine, it remains unknown whether prolactin has any salutary effects on the depressed immune responses following severe hemorrhage. To study this, mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 60 min, then adequately resuscitated and divided into two groups. One group received saline vehicle, while the other group received prolactin (100 micro g/25 g body weight, s.c.) immediately before resuscitation. Two hours thereafter, peritoneal (pMphi) and splenic macrophages (sMphi) were harvested and assessed not only for their ability to release IL-1 and IL-6, but also for cytokine gene expression using semiquantitative reverse transcription and PCR. In an additional group, mice were subjected to sepsis by cecal ligation and puncture 3 days after hemorrhage. Hemorrhage markedly decreased the ability of pMphi and sMphi to release IL-1 and IL-6. This was, however, associated with increased mRNA expression for IL-1beta and IL-6 and increased serum corticosterone levels. Following prolactin treatment of hemorrhaged mice, IL-1beta and IL-6 mRNA levels as well as cytokine release capacity and blood corticosterone levels were comparable to the values in sham animals. Prolactin also improved the survival of animals subjected to sepsis after hemorrhage. Thus, the immunosuppression following hemorrhage appears to be mediated and modulated by hormones from the hypothalamic-pituitary-adrenal axis. Furthermore, prolactin represents a novel immunomodulating hormone for the treatment of immunodepression encountered after hemorrhagic shock and for decreasing the mortality from subsequent sepsis under those conditions.

Prolactin administration following hemorrhagic shock improves macrophage cytokine release capacity and decreases mortality from subsequent sepsis

Although prolactin is reported to counteract the immunosuppressive effects of glucocorticoids, cyclosporine, and morphine, it remains unknown whether prolactin has any salutary effects on the depressed immune responses following severe hemorrhage. To study this, mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 60 min, then adequately resuscitated and divided into two groups. One group received saline vehicle, while the other group received prolactin (100 micro g/25 g body weight, s.c.) immediately before resuscitation. Two hours thereafter, peritoneal (pMphi) and splenic macrophages (sMphi) were harvested and assessed not only for their ability to release IL-1 and IL-6, but also for cytokine gene expression using semiquantitative reverse transcription and PCR. In an additional group, mice were subjected to sepsis by cecal ligation and puncture 3 days after hemorrhage. Hemorrhage markedly decreased the ability of pMphi and sMphi to release IL-1 and IL-6. This was, however, associated with increased mRNA expression for IL-1beta and IL-6 and increased serum corticosterone levels. Following prolactin treatment of hemorrhaged mice, IL-1beta and IL-6 mRNA levels as well as cytokine release capacity and blood corticosterone levels were comparable to the values in sham animals. Prolactin also improved the survival of animals subjected to sepsis after hemorrhage. Thus, the immunosuppression following hemorrhage appears to be mediated and modulated by hormones from the hypothalamic-pituitary-adrenal axis. Furthermore, prolactin represents a novel immunomodulating hormone for the treatment of immunodepression encountered after hemorrhagic shock and for decreasing the mortality from subsequent sepsis under those conditions.

Enhanced immune responses in females, as opposed to decreased responses in males following haemorrhagic shock and resuscitation

Although haemorrhagic shock produces immunodepression in both humans and experimental animals, no information is available concerning gender differences in the immune and endocrine response to shock. To study this, male and female (proestrus and diestrus) C3H/HeN mice (25 g body weight) were bled and maintained at a mean arterial blood pressure of 35 +/- 5 mmHg for 1 h and then adequately resuscitated. The animals were killed at 2 h after resuscitation to obtain splenocytes, macrophages (M phi, peritoneal and splenic), as well as whole blood. IL-1 release by M phi, splenocyte proliferative capacity and splenocyte IL-3 release in female mice was significantly increased. Male mice, however, showed decreased release of all interleukins (IL-1, 2, 3, 6) as well as splenocyte proliferative capacity after shock. Plasma corticosterone levels decreased in proestrus female mice, as opposed to increased levels in males following shock. Corticosterone may therefore, be in part responsible for the observed gender differences. To the authors' knowledge, this is the first study which shows that immune responsiveness in female mice is enhanced after haemorrhagic shock, as opposed to decreased responsiveness in males. Thus, unlike males which exhibit increased susceptibility to sepsis/infections, females should be able to better tolerate the deleterious effects of shock.

Mechanism of immunosuppression in males following trauma-hemorrhage. Critical role of testosterone

OBJECTIVE

To determine whether male sex steroids contribute to the depression in cell-mediated immunity following trauma-hemorrhage and resuscitation.

DESIGN

Two weeks before the induction of soft-tissue trauma (2.5-cm midline laparotomy) and hemorrhagic shock (mean [+/-SEM] blood pressure, 35 +/- 5 mm Hg), male C3H/HeN mice were castrated or sham castrated. Following trauma-hemorrhage, the mice were resuscitated and killed 24 hours thereafter to obtain whole blood and the spleen.

RESULTS

Splenocyte proliferation and splenocyte interleukin-2 and interleukin-3 release were significantly depressed in sham-castrated animals after trauma-hemorrhage. In contrast, these variables in castrated mice after trauma-hemorrhage were similar to those in sham-operated animals. Corticosterone plasma levels were significantly elevated in both trauma-hemorrhage groups compared with those in sham-operated mice. Plasma testosterone levels were undetectable in castrated animals and detectable in sham-castrated mice.

CONCLUSIONS

Castration before soft-tissue trauma and hemorrhagic shock maintains normal immune function in male mice, but sham-castrated male mice show significant immunodepression. The maintenance of immune function by androgen deficiency does not seem to be related to changes in the release of corticosterone. We conclude that male sex steroids are involved in the immunodepression observed after trauma-hemorrhage. Thus, the use of testosterone-blocking agents following trauma-hemorrhage should prevent the depression of immune functions and decrease the susceptibility to sepsis under those conditions.

Immune function is more compromised after closed bone fracture and hemorrhagic shock than hemorrhage alone

OBJECTIVE

To determine whether closed bone fracture in conjunction with hemorrhagic shock compromises immune functions more severely than hemorrhagic shock alone.

DESIGN

In a randomized, controlled trial, closed bone fracture of the right lower leg and/or hemorrhagic shock (mean +/- SEM arterial blood pressure, 35 +/- 5 mm Hg for 90 minutes) were induced in male C3H/HeN mice (weight, 25 g). Animals subjected to hemorrhage were resuscitated with the shed blood and lactated Ringer solution. At 72 hours after the experiment, all animals were killed to obtain whole blood, splenocytes, and splenic and peritoneal macrophages. Macrophage interleukin-1 and splenocyte interleukin-2 and interleukin-3 release were determined by bioassay, and splenocyte proliferation was measured by tritiated thymidine incorporation.

RESULTS

Closed bone fracture alone did not affect immune functions 72 hours after the trauma. Hemorrhagic shock, however, induced a significant depression of splenocyte and macrophage functions. Bone fracture followed by hemorrhagic shock further depressed splenocyte proliferation and splenocyte interleukin-2 and interleukin-3 release as well as interleukin-1 release.

CONCLUSION

Since bone injury coupled with hemorrhagic shock produces more severe depression of immune functions than hemorrhage alone, bone injury appears to play a contributory role in further depressing immune functions in trauma patients who experience major blood loss.

Increased melatonin levels after hemorrhagic shock in male and female C3H/HeN mice

Although hemorrhagic shock leads to significant alterations of several hormones, e.g. ACTH, corticosterone and beta-endorphin, it is not known whether plasma melatonin levels are affected under this condition and if so, whether the effects are comparable in males and females. Using a radioimmunoassay, it was found that plasma melatonin levels were significantly increased in male and proestrus female C3H/HeN mice immediately after hemorrhagic shock. However, in male mice, by two hours after hemorrhage and resuscitation, plasma melatonin returned to levels comparable to those seen in control and sham-operated animals. Proestrus female mice, on the other hand, showed significantly increased plasma melatonin levels at two hours after surgery when compared to unoperated control animals. Although the significance and biological role of the transient increased plasma melatonin levels after hemorrhagic shock remain to be determined, it appears that the pineal gland and/or an extrapineal source of melatonin, of both male and proestrus female mice responds to severe hypotension by increased release of melatonin.

Melatonin administration attenuates depressed immune functions trauma-hemorrhage

The pineal hormone melatonin has been used in clinical trials in patients suffering from AIDS and also as an adjuvant for cancer therapy. Although melatonin has been reported to have beneficial effects in some animal models of immune dysfunction, it remains unknown whether this hormone has any salutary effects on immunity following soft-tissue trauma and/or major blood loss. To study this, soft-tissue trauma (2.5-cm midline laparotomy) and hemorrhagic shock (arterial BP 35 +/- 5 mm Hg) were induced in C3H/HeN mice. The mice were resuscitated after 90 min of hypotension with the shed blood and lactated Ringer's solution. Treatment with saline, vehicle, or melatonin (10 mg/kg BW) subcutaneously was administered in the evening of the day of surgery and again on the following evening. All animals were sacrificed at 48 hr following trauma-hemorrhage and resuscitation to obtain plasma, splenocytes, as well as splenic and peritoneal macrophages (Mphi). The results indicate that melatonin administration after trauma-hemorrhage significantly improved the depressed immune functions, as evidenced by the restoration of Mphi IL-1 and IL-6 release, as well as significantly improved splenocyte IL-2 and IL-3 release and splenocyte proliferative capacity. No differences in circulating corticosterone levels between vehicle- and melatonin-treated animals were observed. This is the first study to show that melatonin, which is reported to be free of adverse side effects, can be considered a safe and effective therapeutic agent for restoring the depressed immunological function after soft-tissue trauma and hemorrhagic shock.

Prolactin: a novel and safe immunomodulating hormone for the treatment of immunodepression following severe hemorrhage

Recent studies have shown that the anterior pituitary hormone prolactin, together with various cytokines, plays an important role in maintaining normal immune responses. Although there is evidence that prolactin may be a significant immunotropic hormone that can counteract the immunosuppressive effects of drugs such as cyclosporine, morphine, or glucocorticoids, it remains unknown whether prolactin administration has any salutary effects on the depressed immune responses following severe hemorrhage. To study this, mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 60 min, then adequately resuscitated and segregated into two groups. One group received saline-vehicle (hem-SS); animals in the other group were treated with prolactin (hem-PRL) (100 micrograms per 25 g BW, subcutaneously) immediately before resuscitation. Two hours following saline or prolactin injection, splenocytes (SPL) were harvested and assessed for proliferative capacity (PC) and their ability to release IL-2 and IL-3. Supernatant lymphokine levels were determined by bioassay. The proliferative capacity of the splenocytes, as well as their ability to release IL-2 and IL-3, was significantly depressed in the vehicle-treated hemorrhaged animals, compared to shams. Treatment with prolactin restored the depressed splenocyte functions seen after severe hemorrhage. These results support the notion that the immunosuppression following hemorrhage and trauma may be mediated by hormones from the hypothalamic-pituitary-adrenal axis. Furthermore, our results suggest that the use of prolactin, which did not produce any adverse hemodynamic effects, represents a novel and safe immunomodulating hormone for the treatment of immunodepression following severe blood loss.

Prolactin inhibits the increased cytokine gene expression in Kupffer cells following haemorrhage

Kupffer cells are an important source of proinflammatory cytokines and contribute to the systemic inflammatory response observed following haemorrhagic shock. The systemic release of cytokines, such as TNF-alpha, IL-1 beta, IL-6, etc., has been associated with the decreased host immune and organ dysfunction following hypotension. Studies indicate that anterior pituitary hormone prolactin (PRL) plays an important role in the regulation of lymphocyte proliferation and macrophage function in vivo, as well as in vitro. However, it is not known what effects PRL administration has on Kupffer cells proinflammatory mediator release following haemorrhage. Therefore, it was the aim of this study to determine the effect of in vivo PRL administration on cytokine gene expression in Kupffer cells after haemorrhage. To study this, C3H/HeN male mice were bled to and maintained at a mean arterial pressure of 35 mmHg for 60 minutes, then resuscitated with shed blood, and segregated into two groups: one group was treated with PRL (100 micrograms/25 g body weight subcutaneously) while the other group received saline-vehicles. This was followed with lactated Ringer's solution (2 x the volume of shed blood). Two hours thereafter, the animals were sacrificed, Kupffer cells were isolated and stimulated with or without 10 micrograms/ml LPS for 1 hour. Total RNA was extracted and cytokine mRNA was detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results demonstrated that haemorrhage markedly increased the level of mRNA for IL-1 beta, IL-6, TGF-beta and TNF-beta in Kupffer cells. However, in vivo PRL treatment significantly decreased the cytokine gene expression in Kupffer cells following haemorrhage. This indicates that PRL may be useful in blunting the systemic inflammatory response associated with cell and organ depression following shock.

Effect of surgical trauma on splenocyte and peritoneal macrophage immune function

Although previous studies have shown that simple laparotomy produces a depression in peritoneal macrophage (Mphi) antigen presentation capacity, it remains unknown whether the adverse effects of laparotomy are limited to peritoneal Mphi or whether such an insult also affects splenocyte immune function. To study this, mice were anesthetized and a 1-inch midline abdominal incision was made, followed by abdominal closure. At 2 and 24 hours after the surgical procedure, the animals were killed, splenocyte cultures established and stimulated for 48 hours with concanavalin A (2.5 micrograms/mL), while peritoneal macrophage cultures were stimulated with LPS (10 micrograms/mL). The proliferative capacity of the splenocytes, as well as their ability to release interleukin-2 and interleukin-3, was markedly decreased at 2 as well as 24 hours after laparotomy. Furthermore, the release of interleukin-6 by splenic and peritoneal macrophages from animals that underwent laparotomy were also significantly depressed at both 2 and 24 hours. These results support the concept that surgical stress in the form of midline laparotomy per se is sufficient to produce a significant impairment in cell-mediated immunity, thus setting the stage for increased incidence of postoperative complications.

PAF-antagonist administration after hemorrhage-resuscitation prevents splenocyte immunodepression

A number of studies have suggested that the inflammatory and chemotactic autocoid platelet activating factor (PAF), together with various cytokines, plays an important role in the pathophysiology of trauma, sepsis, and shock. However, little is known about PAF's contribution to the immunosuppression associated with hemorrhage. The aim of our study was, therefore, to determine if the use of a PAF-antagonist following hemorrhage has any salutary effects on splenocyte lymphokine production. To study this, mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 60 min. The mice were then segregated into three groups and were resuscitated with shed blood plus lactated Ringer's solution (2x the volume of shed blood), containing either a potent PAF-antagonist (Ro 24-4736, a thienodiazepine) in dimethyl sulfoxide (DMSO) or DMSO-vehicle. Sham-operated mice received either DMSO-vehicle in saline or saline alone. Twenty-four hours thereafter the animals were sacrificed and splenocyte cultures established and stimulated for 48 hr with Con A (2.5 micrograms/ml). Supernatant lymphokine levels were determined by bioassay. The cellular release of interleukin-2 and -3 (IL-2 and IL-3) by splenocytes was significantly depressed in the nontreated or vehicle-treated hemorrhaged animals compared to shams. Treatment with the PAF-antagonist Ro 24-4736 restored IL-2 and IL-3 release values to levels comparable to those of the sham-operated animals. Thus, (1) PAF appears to play a significant role in hemorrhage-induced immunosuppression and (2) the use of a PAF-antagonist to uncouple the PAF-generated feedback loops prevents the depression in splenocyte function following hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)

Trauma-hemorrhage causes prolonged depression in cellular immunity

A number of clinical studies have shown that multiple and severe trauma causes immunosuppression and increases the susceptibility to sepsis. However, because there is a close temporal relationship between trauma and hemorrhage in humans, it is difficult to dissociate the effects of tissue trauma versus hemorrhage on immunity in the clinical setting. Studies in mice have shown that simple hemorrhage per se as well as laparotomy alone produces a marked depression in cellular immunity and no difference was seen in the extent of depression at 2 h if these two insults were combined. Nonetheless, it remains unknown whether the combined model of trauma-hemorrhage produces a more protracted depression in immune function. To study this, 5 days after either sham operation, laparotomy (i.e. trauma), hemorrhage alone (35 mmHg for 1 h, followed by resuscitation), or the combination of laparotomy and hemorrhage, mice (C3H/HeN) were sacrificed, after which splenocyte and peritoneal macrophage cultures were established. The proliferative capacity of the splenocytes, as well as their ability to release IL-2 and IL-3, was markedly decreased in the trauma-hemorrhage animals but was normal in the other groups. Furthermore, the release of IL-6 by peritoneal macrophages from animals that underwent trauma-hemorrhage was also significantly depressed. These results support the concept that traumatic injury in the form of a midline laparotomy combined with hemorrhage produces a more protracted impairment in cell-mediated immunity than laparotomy or hemorrhage alone.

A novel nonanticoagulant heparin improves splenocyte and peritoneal macrophage immune function after trauma-hemorrhage and resuscitation

Recent studies have shown that heparinization of animals prior to or even after hemorrhagic shock improves tissue perfusion and organ function. However, the anticoagulant properties of conventional heparin preclude its clinical use in trauma care. The aim of our study, therefore, was to determine whether chemically modified heparin, i.e., a novel nonanticoagulant heparin (GM1892), which does not have significant anticoagulant activity (approximately 2% of the anticoagulant activity of conventional heparin), produces any beneficial effects on splenocyte and macrophage immune function following trauma-hemorrhage and resuscitation. To determine this, following the induction of tissue trauma (i.e., a midline laparotomy), mice were bled to and maintained at a mean arterial pressure of 35 mm Hg for 1 hr. The animals then received GM1892 (7 mg/kg body wt), conventional heparin (7 mg/kg body wt), normal saline prior to resuscitation with three times the volume of shed blood with Ringer's lactate. Two hours after resuscitation the animals were sacrificed, splenocytes were isolated, and splenic, as well as peritoneal macrophage, cultures were established. The ability of the splenocytes to release IL-2 and IL-3 in response to mitogen was markedly improved in hemorrhaged animals which were treated with GM1892 or conventional heparin compared to saline-treated mice. Furthermore, the capacity of splenic and peritoneal macrophages to release IL-6 was restored in the hemorrhaged animals that received GM1892 or conventional heparin.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytokine gene expression in splenic macrophages and Kupffer cells following haemorrhage

TNF-alpha, IL-1, IL-6 and TGF-beta are important macrophage-derived mediators which play the pleiotropic role in inflammatory, metabolic, hematopoietic and immunologic processes. Studies have shown that haemorrhagic shock without significant tissue trauma induces profound immunosuppression which is associated with elevated plasma levels of TNF-alpha IL-1, IL-6 as well as TGF-beta. Furthermore, Kupffer cells but not the splenic M phi isolated from post-haemorrhaged animals showed an increased capacity to release inflammatory cytokines in response to LPS stimulation in vitro. However, it remains unknown whether the innate (i.e. in the absence of LPS stimulation) cytokine genes expression in Kupffer cells and splenic M phi is affected by haemorrhage. To determine this, C3H/HeN male mice were bled to and maintained at a mean arterial blood pressure of 35 mmHg for 60 min, and then adequately resuscitated. Splenic macrophages and Kupffer cells were isolated at 1 h after haemorrhage. Total RNA was extracted and cytokine mRNA was detected by semi-quantitative reverse transcription and polymerase chain reaction (RT-PCR). The results demonstrate that haemorrhage significantly elevated the mRNA accumulation of TNF-alpha, IL-1 beta, TGF-beta while IL-6 gene expression in Kupffer cells and splenic M phi was only slightly increased. Since Kupffer cells but not the splenic M phi showed increased cytokine release, it could be concluded that the differential regulation of cytokine release by these two macrophage populations following haemorrhage may be due to the divergence of the cytokine at the translational level.(ABSTRACT TRUNCATED AT 250 WORDS)

Peritoneal macrophages show increased cytokine gene expression following haemorrhagic shock

Tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-1 and transforming growth factor-beta (TGF-beta) have been recognized as important mediators of pathophysiological and immunological events associated with shock. Previous studies have indicated that although peritoneal macrophage (PM phi) antigen presentation was depressed following haemorrhage, the cytokine release capacity in response to lipopolysaccharide (LPS) was not affected in vitro. To determine the effect of haemorrhagic shock on PM phi cytokine mRNA transcription, C3H/HeN male mice were bled to and maintained at a mean arterial blood pressure of 35 mmHg for 60 min, and then adequately resuscitated. PM phi were isolated at 1 or 24 hr after haemorrhage and were incubated without or with 10 micrograms LPS/ml for 1 hr. Total RNA was then extracted followed by Northern blot analysis, as well as semi-quantitative reverse transcription and polymerase chain reaction (RT-PCR). The results of Northern blot analysis indicated that haemorrhage markedly increased LPS-induced IL-1 beta, IL-6, and TNF-alpha mRNA accumulation in PM phi at both 1 and 24 hr after haemorrhage and resuscitation. Furthermore, competitive RT-PCR demonstrated that mRNA of IL-1 beta, IL-6, TNF-alpha, as well as TGF-beta, was increased in PM phi obtained 1 hr after haemorrhage either with or without LPS stimulation. The data from Northern blot analysis and semi-quantitative RT-PCR also revealed that LPS enhanced the effect of haemorrhage on PM phi cytokine gene expression. Thus, following haemorrhage, PM phi showed elevated cytokine mRNA accumulation which was not followed by an increased ability to release cytokines in response to LPS in vitro. These results, therefore, suggest that different mechanisms regulate gene expression and subsequent cytokine secretion by PM phi following haemorrhage.