Delayed recovery and late development of complex regional pain syndrome in patients with an isolated fracture of the distal radius: prediction of a regional inflammatory response by early signs.

We studied prospectively the regional inflammatory response to a unilateral distal radial fracture in 114 patients at eight to nine weeks after injury and again at one year. Our aim was to identify patients at risk for a delayed recovery and particularly those likely to develop complex regional pain syndrome. In order to quantify clinically the inflammatory response, a regional inflammatory score was developed. In addition, blood samples were collected from the antecubital veins of both arms for comparative biochemical and blood-gas analysis. The severity of the inflammatory response was related to the type of treatment (Kruskal-Wallis test, p = 0.002). A highly significantly-positive correlation was found between the regional inflammatory score and the length of time to full recovery (r(2) = 0.92, p = 0.01, linear regession). A regional inflammatory score of 5 points with a sensitivity of 100% but a specificity of only 16% also identified patients at risk of complex regional pain syndrome. None of the biochemical parameters studied correlated with regional inflammatory score or predicted the development of complex regional pain syndrome. Our study suggests that patients with a distal radial fracture and a regional inflammatory score of 5 points or more at eight to nine weeks after injury should be considered for specific anti-inflammatory treatment.

Pentoxifylline does not improve outcome in a murine model for the multiple-organ dysfunction syndrome.

OBJECTIVE: To investigate the effects of pentoxifylline (PTX) administration in a murine model for the multiple-organ dysfunction syndrome (MODS). DESIGN AND SETTING: Prospective double-blind randomized animal study in a university research laboratory. INTERVENTIONS AND MEASUREMENTS: Sixty C57BL/6 mice were given an aseptic intraperitoneal injection of lipopolysaccharide followed after 6 days by zymosan (day 0) at a dose of either 0.9 or 1.0 mg/g body weight. Starting on day 0 mice were administered PTX at a dose of 80 mg/kg body weight or saline per os every 8 h. On day 17 surviving animals were killed, and their liver, lungs, spleen, and kidneys were collected. RESULTS: Mortality, course of body temperature, body weight, and macroscopic lung damage were similar between zymosan-treated groups. Administration of PTX did not significantly alter survival, body temperature, body weight, or macroscopic lung damage. In addition, there were no significant differences in organ weights between mice that received PTX and mice that received PBS. Although PTX inhibited the lipopolysaccharide-induced increase in tumor necrosis factor alpha and interleukin 6 expression (but not interleukin 1beta expression) at both mRNA and protein level in a murine macrophage cell line, tumor necrosis factor alpha mRNA expression in the livers of PTX-treated mice was not significantly inhibited. CONCLUSIONS: The results reported here do not support the hypothesis that PTX improves outcome in zymosan-induced multiple-organ dysfunction in mice.

Complex regional pain syndrome type I (RSD): pathology of skeletal muscle and peripheral nerve.

BACKGROUND: Reflex sympathetic dystrophy (RSD) (recently reclassified as complex regional pain syndrome type I) is a syndrome occurring in extremities and, when chronic, results in severe disability and untractable pain. RSD may be accompanied by neurologic symptoms even when there is no previous neurologic lesion. There is no consensus as to the pathogenic mechanism involved in RSD. To gain insight into the pathophysiology of RSD, we studied histopathology of skeletal muscle and peripheral nerve from patients with chronic RSD in a lower extremity. METHODS: In eight patients with chronic RSD, an above-the-knee amputation was performed because of a nonfunctional limb. Specimens of sural nerves, tibial nerves, common peroneal nerves, gastrocnemius muscles, and soleus muscles were obtained from the amputated legs and analyzed by light and electron microscopy. RESULTS: In all patients, the affected leg showed similar neurologic symptoms such as spontaneous pain, hyperpathy, allodynia, paresis, and anesthesia dolorosa. The nerves showed no consistent abnormalities of myelinated fibers. In four patients, the C-fibers showed electron microscopic pathology. In all patients, the gastrocnemius and soleus muscle specimens showed a decrease of type I fibers, an increase of lipofuscin pigment, atrophic fibers, and severely thickened basal membrane layers of the capillaries. CONCLUSION: In chronic RSD, efferent nerve fibers were histologically unaffected; from afferent fibers, only C-fibers showed histopathologic abnormalities. Skeletal muscle showed a variety of histopathologic findings, which are similar to the histologic abnormalities found in muscles of patients with diabetes.

Pain and reduced mobility in complex regional pain syndrome I: outcome of a prospective randomised controlled clinical trial of adjuvant physical therapy versus occupational therapy.

There are no adequate comparative studies on physical therapy (PT) versus occupational therapy (OT) in patients with complex regional pain syndrome I (CRPS I). Therefore, we conducted a prospective randomised clinical trial to assess their effectiveness. The outcomes regarding reducing pain and normalising active range of motion (AROM) are discussed. Included in the study were 135 patients who had been suffering from CRPS I of one upper extremity for less than one year. They were randomly assigned to one of three groups: PT, OT, or control (social work, CT). Measurements were taken at base-line (t0), after 6 weeks, and after 3, 6 and 12 months (t1 to t4). Pain was measured on four visual analogue scales (VAS) and the McGill Pain Questionnaire, Dutch Language Version (MPQ-DLV). The AROM was recorded relative to the contralateral side. Explorative statistical evaluations were performed (Wilcoxon; alpha=0.05). PT and to a lesser extent OT, resulted in more rapid improvement in the VAS scores than CT, especially for the VAS during or after effort (P<0.05 at t1 to t3). PT was superior to CT and OT according to the MPQ-DLV particularly at t4. Improvement on the MPQ-DLV over the year was significantly greater for PT than for OT and CT (P<0.05). PT -and to a lesser degree OT- led to better results than CT for the AROM of the wrist, fingers and thumb at t1 to t3 (most-times P<0.05 for PT), but the improvements over the year were not significantly different. Our results indicated that PT, and to a lesser extent OT, were helpful for reducing pain and improving active mobility in patients with CRPS I of less than one year duration, localised in one upper extremity.

Evaluation of infectious diabetic foot complications with indium-111-labeled human nonspecific immunoglobulin G.

Osteomyelitis of the foot is a well-known complication of diabetes mellitus. In this study, the validity of 111In-labeled human nonspecific immunoglobulin G (IgG) scintigraphy was studied in 16 diabetic patients with foot ulcers, gangrene or painful Charcot joints. In all patients, plain radiographs, conventional bone scan images and 111In-IgG images were recorded. The results were verified by histologic examination of surgical specimens in patients who did not respond to antibiotic treatment within 2-3 wk (10 lesions) or long-term clinical follow-up of at least 6-mo (16 lesions). On the bone scans, all seven osteomyelitic foci were detected. However, 19 additional foci not due to osteomyelitis were seen. The absence of true-negative bone scans in this study resulted in a specificity of 0%. On the plain radiographs, four of seven osteomyelitis foci were detected; for 111In-IgG scintigraphy, six of seven (sensitivity 57% and 86%, respectively). Plain radiographs correctly ruled out osteomyelitis in 15 of 19 lesions, 111In-IgG scintigraphy in 16 of 19 (specificity 79% and 84%, respectively). All imaging procedures gave false-positive results in penetrating ulcers over the calcaneus in two patients and in one patient with a Charcot joint, most likely due to recent fractures. A false-negative 111In-IgG study was observed in a patient with severe arterial angiopathy. Accurate estimation of probable osteomyelitis was not possible from the results of soft-tissue cultures, since in only 6 of 12 positive cultures, osteomyelitic foci could be proven. Indium-111-IgG scintigraphy can contribute to adequate evaluation of osteomyelitis in diabetic foot complications because it improves specificity when compared to bone scan and radiographic findings and improves sensitivity in comparison to plain radiographs.

Role of neutrophils in burn-induced microvascular injury in the intestine.

The present study evaluated burn-induced vascular permeability alterations of rat small intestine in vivo and assessed the effect of neutrophil depletion in burn-injured rats on the altered intestinal microvascular permeability. 125I-labeled bovine serum albumin (125I-BSA) was injected intravenously, and its leakage from circulation into the intestinal tissue was determined by measuring tissue counts of 125I-BSA. Compared with sham, vascular albumin permeability increased 1.7-fold on day 1 post-burn and 3.0-fold on day 3 post-burn in ileum. In the jejunum, albumin permeability increased 1.8- and 2.5-fold on day 1 and day 3 post-burn, respectively. Intestinal tissue edema, determined as increases in tissue water contents, was noted in both intestinal segments on day 1 post-burn; no further increase in edema was found on day 3 post-burn. Neutrophil depletion before burn injury prevented the vascular leakage of albumin and edema in the ileum and jejunum on day 1 post-burn. On day 3 post-burn, the effect of prior neutrophil depletion on vascular permeability was less marked, and edema formation was not affected at all. These findings indicate that an absence of neutrophils prevents the loss of intestinal vascular barrier properties only in the initial periods after burns.

Gradual development of organ damage in the murine zymosan-induced multiple organ dysfunction syndrome.

A well defined animal model is a prerequisite to test intervention strategies aimed at preventing the development of the multiple organ dysfunction syndrome. This study compares changes in clinical parameters to histopathologic changes in tissues, observed over a 12 day period after a single intraperitoneal injection of zymosan in C57BL/6 mice. Administration of zymosan induced gradual and progressive changes in wet and dry organ weight of the liver, kidneys, and particularly, lungs and spleen that correlated with increasing histopathology. From 6 days after zymosan injection onwards, hemorrhagic spots were found in the lungs evolving into massive hemorrhages at 12 days, when thickened interstitial walls and loss of the honey comb-like structures were observed. The liver displayed progressive accumulation of macrophage-like and mononuclear cells. After 12 days, numerous granuloma-like structures were disseminated throughout the liver parenchyma. The spleen displayed great changes in red and white pulp with increasing numbers of megakaryocytes and plasma-like cells. In the kidneys, necrosis of the tubular epithelium adjacent to granulomas on the ventral (peritoneal) side was found. In mice, a single intraperitoneal challenge with zymosan leads to progressive multiple organ damage, which becomes apparent at some time after the insult. This animal model displays a number of features encountered in human multiple organ dysfunction syndrome and appears suitable to conduct intervention studies.

Organ damage is preceded by changes in protein extravasation in an experimental model of multiple organ dysfunction syndrome.

Our objective was to determine the serial evolution of vascular permeability as measured by protein extravasation in various organs during the development of zymosan-induced multiple organ dysfunction syndrome (MODS). We evaluated the biodistribution of 111Indium-labeled nonspecific polyclonal immunoglobulin G (111In-IgG). On days 2, 5, 8, and 12 after intraperitoneal challenge with 1 mg/g zymosan, mice were killed. Heart, liver, spleen, kidneys, and the mesenteric lymph node complex and tissue samples of muscle, ileum, and colon were dissected free and weighed. 24 h before death, 10 micrograms of IgG labeled with 2 MBq 111In was injected i.v. Relative organ weights (ROW), wet to dry weight ratios (WDR), and a permeability index (PI) were calculated. ROW increased gradually until day 12. WDR also increased gradually in most organs. Lung WDR, however, initially increased, with a subsequent return to normal. Splenic WDR did not change over time. Liver, spleen, ileum, and colon PI were the highest on day 2, followed by a decrease toward normal. Lung PI showed a triphasic course with peak values at days 2 and 12. Mesenteric lymph node complex-PI was continuously elevated. WDR (tissue edema) and PI (protein extravasation) have different courses in various organs. Most organs displayed an early increase in PI, followed by a late decrease, while ROW (organ damage) was still increasing. It appears that organ damage is preceded by an increased protein extravasation.

Striated muscle microvascular response to zymosan-induced generalized inflammation in awake hamsters.

The effect of zymosan-induced generalized inflammation on the microcirculation of distant striated skin muscle was studied for a 12 day period in awake Syrian golden hamsters (n = 18) using the dorsal skinfold chamber model and intravital fluorescence microscopy. Intraperitoneal zymosan exposure (125 mg/100 g body weight) induced significant nutritive perfusion failure in the distant striated muscle tissue at Day 1 without complete recovery over the 12 day observation period, as indicated by the marked reduction of functional capillary density when compared with both baseline values and values of sham-treated control animals. Moreover, intraperitoneal zymosan exposure induced endothelial disintegration, as demonstrated by the continuous increase of macromolecular leakage throughout the 12 days of observation. Strikingly, zymosan did not induce significant leukocyte adherence to the endothelial lining of postcapillary and collecting venules of the striated muscle tissue. Thus, we conclude that in this model of generalized inflammation nutritive perfusion failure and loss of endothelial integrity in distant striated muscle is not mediated by activated leukocytes, but must rather be attributed to direct toxic effects of mediators, elicited by the local (intraperitoneal) zymosan challenge and systemically released.

Mediators of multiple organ failure.

Multiple Organ Failure (MOF) has largely been attributed to bacterial sepsis, though conclusive evidence of an essential role for bacteria and/or their endotoxins is still lacking. On the other hand, MOF and the clinical syndrome of sepsis may be aseptically induced in germ-free animals. This paper reviews the evidence that excessive activation of endogenous humoral mediators and inflammatory cells may cause this highly lethal syndrome.

Early detection of hemorrhagic hypovolemia by muscle oxygen pressure assessment: preliminary report.

Skeletal muscle PO2 was studied during graded hemorrhagic shock in Labrador dogs by means of a polarographic needle PO2 electrode. Compared to hemodynamic, blood gas, biochemical, and hematologic variables, a shift to the left of the cumulative histogram of skeletal muscle PO2 was the earliest and most sensitive indicator of impaired skeletal muscle oxygenation. The mean arterial blood pressure and the mean of the medians of the skeletal muscle PO2, respectively, were as follows: during the control period 125 and 38.1 mm Hg, during the imminent shock period 143 and 24.5 mm Hg, and during the shock period 89 and 5.1 mm Hg. This electrode is suitable for clinical use.

Early detection of shock in critically ill patients by skeletal muscle PO2 assessment.

The usefulness of skeletal muscle PO2 assessment in monitoring patients at risk of shock was evaluated in 20 critically ill patients. A shock score, inotropic score, and combined inotropic-shock score were calculated. If the median skeletal muscle PO2 assessment was more than 31.5 mm Hg, no shock occurred in the period from 4 hours before to 6 hours after the measurement. The risk of shock occurring during the first 2 hours after the skeletal muscle PO2 assessment was 2.2 times higher if median skeletal muscle PO2 assessment was below 22.5 mm Hg. If inotropes were administered, no significant difference was found in the incidence of shock if skeletal muscle PO2 was below or above 22.5 mm Hg. Skeletal muscle PO2 assessment enables the determination of the severity of shock and determination of risk of shock in critically ill patients, provided no treatment with inotropes has been instituted.

Does selective decontamination of the gastrointestinal tract prevent multiple organ failure? An experimental study.

Gut bacteria have been incriminated as causing or contributing to generalized sepsis with multiple organ failure in severely ill patients, and selective decontamination of the gastrointestinal tract of Enterobacteriaceae has been claimed to decrease septic complications in these patients. We studied the effects of selective decontamination of the gastrointestinal tract on survival and organ function in an experimental model of sepsis with multiple organ failure. Wistar rats were inoculated intraperitoneally with zymosan and randomized into control or treatment groups (trimethoprim or streptomycin sulfate). Selective decontamination effectively prevented bacterial translocation of Enterobacteriaceae. However, only early mortality was decreased, and only so in the streptomycin-treated rats. Selective decontamination did not result in a significantly better condition of the surviving animals on day 12.

Multiple-organ failure and sepsis without bacteria. An experimental model.

Multiple-organ failure is generally attributed to bacterial infection, although a correlation with positive blood cultures is not consistently found. Consequently, we studied the effects of a local nonbacterial inflammatory stimulus on distant organ functions and metabolism. Wistar rats were inoculated intraperitoneally with zymosan. Heart and ventilatory rates, oxygen consumption, and body temperature were measured. Survivors were killed at day 12 for blood analysis, weighing of organs, and microscopy. Intraperitoneal zymosan resulted in an early hyperdynamic "septic" response with a 35% mortality. After a few days, oxygen consumption decreased, serum lactate levels increased, and the function of multiple organs deteriorated, while blood cultures remained sterile. The experiment was repeated in germ-free rats with similar results but a lower mortality. We concluded that a severe inflammatory response in itself is capable of inducing multiple-organ failure with "sepsis."

Elimination of various subpopulations of macrophages and the development of multiple-organ dysfunction syndrome in mice.

OBJECTIVE: To evaluate the role of specific macrophage subpopulations in the development of zymosan-induced multiple-organ dysfunction syndrome by selective elimination of liver, splenic, alveolar, and peritoneal macrophages. DESIGN: Randomized animal trial. SETTING: Central animal laboratory at the University Hospital Nijmegen, Nijmegen, the Netherlands. ANIMALS: Male C57Bl/6 mice. INTERVENTIONS: Elimination of macrophages was accomplished by administration of multilamellar liposomes that contained dichloromethylene bisphosphonate (Cl2MBP). Intravenous, intratracheal, and intraperitoneal administrations induced an elimination of liver and splenic, alveolar, and peritoneal and omental macrophages, respectively. Zymosan (1 mg/g) was injected intraperitoneally at day 0. The liposomes that contained Cl2MBP were administered before and after zymosan challenge. At day 12, all surviving mice were killed. MAIN OUTCOME MEASURES: The body weights, temperatures, and mortality rates of the mice were monitored daily. Relative organ weights (ROWs) were calculated from the lungs, liver, spleen, and kidneys after the mice were killed. RESULTS: The liposomes that contained Cl2MBP, administered intravenously before or after zymosan challenge, did not induce significant changes in the body weight, temperature, or mortality rate. The ROW of the liver was significantly decreased in both treatment groups. Elimination of liver and splenic macrophages after zymosan challenge induced an increased ROW of the lung and a decreased ROW of the liver. The liposomes that contained Cl2MBP, administered intratracheally before zymosan challenge, completely prevented deaths. The body weights, temperatures, and ROWs of the mice were not changed. The liposomes that contained Cl2MBP, administered intraperitoneally, did not change the body weight, temperature, or ROW. The liposomes that contained Cl2MBP, administered intraperitoneally before zymosan challenge, increased the mortality from 50% to 90%. CONCLUSIONS: These data show that the elimination of specific macrophage subpopulations and the elimination on specific time points in this model had differential effects, indicating a differential role of specific macrophage subpopulations, either protective or detrimental, in the development of multiple-organ dysfunction syndrome.

Multiple-organ failure. Generalized autodestructive inflammation?

As multiple-organ failure (MOF) has been generally associated with sepsis, the importance of bacterial sepsis was evaluated retrospectively in 55 trauma and 37 intra-abdominal-sepsis patients with MOF. The severity of MOF was graded, and an analysis was made of day of onset, incidence, severity, sequence, and mortality of organ failures. No difference was found between groups in sequence, severity, or mortality of organ failures. In contrast, bacterial sepsis was found in 65% of intra-abdominal-sepsis patients but only in 33% of trauma patients. It is concluded that sepsis is probably not the essential cause of MOF. Instead, an alternative hypothesis is presented involving massive activation of inflammatory mediators by severe tissue trauma or intra-abdominal sepsis, resulting in systemic damage to vascular endothelia, permeability edema, and impaired oxygen availability to the mitochondria despite adequate arterial oxygen transport.

Rational guidelines in renal trauma assessment.

Optimal management in renal trauma necessitates an adequate delineation of location and extent of the renal injury. However, as a result of the rapid rise in the costs of medical care, a complete and elaborate radiographic evaluation of all patients with suspected renal injury no longer seems justified. We reviewed our experience with 622 consecutive cases of renal injury to find the most economical diagnostic sequence with the clearest findings. An intravenous pyelography (IVP) still is the first and mostly the sole examination to do in patients with clinical or laboratory evidence of renal trauma. Microscopic hematuria alone is no longer an indication to perform urography. If indicated, an IVP should be performed as an emergency procedure in all cases and especially in the patient with multiple trauma. Children are more susceptible to renal trauma and require a higher index of suspicion. In the few patients with indeterminate findings on urography, renal angiography must be considered (especially when renal pedicle injury is suspected) or a computerized tomography (CT) scan (especially in the patient with multiple trauma). Ultrasound and CT examinations are not to be done on a routine basis in the initial assessment or the follow-up of renal trauma.

Leg muscle reflexes mediated by cutaneous A-beta fibres are normal during gait in reflex sympathetic dystrophy.

OBJECTIVES: Reflex sympathetic dystrophy (RSD) is, from the onset, characterized by various neurological deficits such as an alteration of sensation and a decrease in muscle strength. We investigated if afferent A-beta fibre-mediated reflexes are changed in lower extremities affected by acute RSD. METHODS: The involvement of these fibres was determined by analyzing reflex responses from the tibialis anterior (TA) and biceps femoris (BF) muscles after electrical stimulation of the sural nerve. The reflexes were studied during walking on a treadmill to investigate whether the abnormalities in gait of the patients were related either to abnormal amplitudes or deficient phase-dependent modulation of reflexes. In 5 patients with acute RSD of the leg and 5 healthy volunteers these reflex responses were determined during the early and late swing phase of the step cycle. RESULTS: No significant difference was found between the RSD and the volunteers. During early swing the mean amplitude of the facilitatory P2 responses in BF and TA increased as a function of stimulus intensity (1.5, 2 and 2.5 times the perception threshold) in both groups. At end swing the same stimuli induced suppressive responses in TA. This phase-dependent reflex reversal from facilitation in early swing to suppression in late swing occurred equally in both groups. CONCLUSIONS: In the acute phase of RSD of the lower extremity there is no evidence for abnormal A-beta fibre-mediated reflexes or for defective regulation of such reflexes. This finding has implications for both the theory on RSD pathophysiology and RSD models, which are based on abnormal functioning of A-beta fibres.

A novel animal model to evaluate oxygen derived free radical damage in soft tissue.

We present a novel animal model which allows the continuous intra-arterial infusion in one hindlimb of non-anaesthetized rats, without inducing ischemia. Using this model the effect of continuous infusion (1 ml/h) for 24 h with tert-butylhydroperoxide (tert-BuOOH) at a concentration of 25 mM on soft tissue of the left hind limb was studied and compared to the effect of saline infusion (control group). The tert-BuOOH-infused foot showed increased skin temperature, increased circumference, redness of the plantar skin, impaired function and increased pain sensation, while in the contralateral foot and in rats only perfused with saline these signs of inflammation were absent (p < 0.01). Histological analysis of the left gastrocnemius muscle showed edema, muscle cell degeneration with a patchy distribution pattern and vascular damage. All these features increased in severity from 4 to 24 h tert-BuOOH infusion. After 24 h of tert-BuOOH infusion infiltration of neutrophils in the interstitium was observed. Vascular permeability, expressed as left to right gastrocnemius muscle 99mTc-IgG uptake ratio, was similarly increased after 4 h (2.09 +/- 0.26) and 12 h (2.04 +/- 0.08) of tert-BuOOH infusion compared to saline (1.05 +/- 0.08) (p < 0.001), and further increased after 24 h (3.84 +/- 0.13): (p < 0.001). In this animal model free radical-related soft tissue damage was induced, by continuous infusion of tert-BuOOH, followed by increasing necrosis and vascular permeability in skeletal muscle coinciding with neutrophilic infiltration.

The Symptom Checklist-90 Revised questionnaire: no psychological profiles in complex regional pain syndrome-dystonia.

Complex regional pain syndrome (CRPS) is a syndrome usually localized in the extremities, mostly occurring after a preceding trauma or operation. Dystonia is present in a minority of CRPS patients, but, when present, leads to severe disability. Various pathological factors have been postulated to present in CRPS-dystonia, such as involvement of the sympathetic system, reorganization of the central nervous system, and psychological distress. In the present study, we investigated the involvement of psychological distress in CRPS-dystonia with the aid of the Symptom Checklist-90 Revised (SCL-90R) questionnaire. The SCL-90R is a multidimensional self-report inventory covering various dimensions of psychological distress. In a population of 1006 CRPS patients, we analyzed the SCL-90R scores of 27 patients with CRPS-dystonia (23 female and 4 male) and compared the scores to sample scores of a control female (n = 577) and a control rehabilitation population (n = 56). Insomnia scored significantly higher in the female CRPS-dystonia population, as compared to the control female population (P < 0.001), and in the total CRPS-dystonia population, as compared to the rehabilitation population (P < 0.01). Remarkable was the significantly higher score of somatization in the rehabilitation population, as compared to the CRPS-dystonia population (P = 0.006). For the other dimensions of psychological distress of the SCL-90R, the scores of the CRPS-dystonia and control populations were similar. With regard to the SCL-90R scores, we conclude that specific psychological profiles are not present in CRPS-dystonia.