Physiologic changes with abdominal wall reconstruction in a porcine abdominal compartment syndrome model.

PURPOSE: Abdominal compartment syndrome (ACS) is a severe complication of ventral hernia repair. The aims of this study were to investigate the effects of intra-abdominal pressure on the physiologic changes of abdominal wall reconstruction and component separation in a porcine model. METHODS: Ventral hernia repair (VHR) was simulated by abdominal fascial imbrication of a 10 × 15 cm defect in 45 Yorkshire pigs assigned to five experimental groups. ACS was simulated by a Stryker endoscopy insufflator with intra-abdominal pressure elevated to 20 mmHg in two groups. Component separation was performed in one of these groups and in one group without ACS. Physiological parameters were measured before and after the procedures and monitored for 4 h. The animals were euthanized for histologic analysis of organ damage. RESULTS: VHR led to an increase in intra-abdominal pressure, bladder pressure, and central venous pressure by an average of 14.89, 13.93, and 14.69 mmHg (p < 0.001) in all animals. Component separation was performed in 25 animals and the three pressures reduced by 9.11, 8.00, 7.89 mmHg (p < 0.001). ACS correlated with higher percentages of large and small bowel necrosis compared to groups without abdominal compartment syndrome. CONCLUSIONS: The results confirm that primary repair of large abdominal wall defects leads to increased intra-abdominal pressure, which can be reduced with component separation. In animals with ACS, component separation may reduce the risk of organ damage. Central venous pressure, bladder pressure, and other physiologic parameters accurately correlated with elevated intra-abdominal pressure and may have utility as markers for diagnosis of ACS.

Vascularized bone marrow-based immunosuppression inhibits rejection of vascularized composite allografts in nonhuman primates.

Vascularized composite allograft (VCA) transplantation (also referred to as composite tissue allotransplantation) has demonstrated clinical success in cases of hand, arm and face transplantation despite prior belief that skin provides an insurmountable barrier to allograft rejection. These overall good outcomes are facilitated by substantial immunosuppressive requirements in otherwise healthy patients, yet still demonstrate frequent rejection episodes. We developed a nonhuman primate model of facial segment allotransplantation to elucidate the unique pathophysiology and immunosuppressive requirements of VCA with addition of concomitant vascularized bone marrow (VBM). Heterotopically transplanted facial segment VCA with VBM treated only with tacrolimus and mycophenolate mofetil (MMF) demonstrated prolonged rejection-free survival, compared to VCA without VBM that demonstrated early rejection episodes and graft loss. While VCA with VBM demonstrated sporadic macrochimerism, acute and chronic rejection and graft loss occurred after discontinuation of immunosuppression. These data support an immunomodulatory role of VBM in VCA that reduces immunosuppressive requirements while providing improved outcomes.

Simultaneous aortic reconstruction and bilateral renal revascularization. Is this a safe and effective procedure?

Between 1982 and 1987, 32 patients with severe aortorenal atherosclerosis had simultaneous aortic and bilateral renal revascularization. All patients were hypertensive. Eighteen patients (56%) had renal insufficiency with a mean serum creatinine (SC) of 2.8 mg/dl. Nine patients had an aortic aneurysm; the remaining 23 patients had aortoiliac occlusive disease of varying severity. Aortic reconstruction was done with either a straight (six patients) or bifurcated (26 patients) Dacron graft. Renal revascularization was accomplished with either bypass (60 arteries) or transaortic endarterectomy (four arteries). One patient died of pulmonary embolism (operative mortality rate 3%). Beneficial blood pressure response was achieved in 28 of 31 survivors, (90%). Among the 18 patients with renal insufficiency, mean SC was 2.80 +/- 1.18 mg/dl preoperatively and 1.65 +/- 0.48 mg/dl postoperatively (p less than 0.001). Among eight patients with severe renal dysfunction before surgery (SC greater than 3 mg/dl), mean SC was 3.90 +/- 0.85 mg/dl before and 1.79 +/- 0.69 mg/dl after operation (p less than 0.001). In follow-up extending to 58 months (mean 27.6 months), five late deaths occurred; cumulative survival was 94% at 2 years and 60% at 4 years. There were no instances of worsening hypertension; one patient had deteriorating renal function. These results indicate that severe aortorenal atherosclerosis can be managed with simultaneous aortic reconstruction and bilateral renal revascularization at low operative risk. In addition, there can be high expectation of significant and persisting benefit in both hypertension and renal dysfunction after operation.

Failure of hemodialysis to diminish psychotic behavior in schizophrenia: behavioral and psychophysiological evaluation.

In a double-blind sham replacement study, eight drug-free schizophrenic patients underwent 10 active and 10 sham hemodialysis for 20 weeks. At the end of the 10 active dialyses, none of the patients appeared to be improved in psychotic, affective, or social symptoms. Active dialysis was associated with a "startle" response in heart rate and skin conductance to auditory stimuli, while sham dialysis was associated with an "orienting" response. Night-recorded sleep electroencephalography was unaffected by active dialysis. Spinal fluid beta-endorphin-like immunoreactivity levels were unchanged after active treatment. The behavioral improvements reported in other studies may be related to "stress," psychotherapeutic support, spontaneous remissions, neuroleptic withdrawal, denial of symptoms, or diagnostic differences. This study did not confirm the claims for hemodialysis as a specific therapeutic intervention in schizophrenia.

Antiseptics in the treatment of bacterial peritonitis in rats.

A controlled mixed peritoneal infection was produced by inoculation of bacteria into the peritoneum and peritonitis was allowed to become established. A laparotomy was performed and peritoneal toilet with a variety of agents was carried out. Local povidone-iodine in the inflamed peritoneum proved to be not only of no benefit but, in fact, to be toxic. In the standard concentrations recommended it proved lethal. Noxythiolin 2.5 per cent also had no beneficial effect. There was a significant difference between the effect of povidone-iodine when instilled into an inflamed peritoneum and instillation into the intact peritoneal cavity. We would advise caution in the use of these antiseptics in any situation in which local defence mechanisms have been compromised as a result of established infection.

Successful creation of arteriovenous fistulas in nonuremic patients with heparin and aspirin therapy.

From November 1977 through June 1979, 26 of 28 nonuremic patients had forearm arteriovenous fistulas successfully created for dialysis, lymphapheresis or vascular access. To improve patency, aspirin and heparin therapy was begun the night before operation and continued postoperatively in all except one patient. No major change in coagulation parameters resulted from this treatment. Twenty-five radial artery to cephalic vein fistulas were created in 23 patients, brachial artery to basilic vein fistulas in 3 patients, and 8 mm polytetrafluoroethylene brachial artery to basilic vein loop grafts in two patients. Early fistula failures (within 11 days) required thrombectomy once in four patients and twice in another patient. A sixth patient was not given heparin or aspirin and required multiple thrombectomies before the graft was removed because of infection. One other patient refused further surgery after two unsuccessful attempts to create an arteriovenous fistula. In the remaining 26 patients, the fistulas have been successfully maintained, and in 18 patients more than 214 dialysis or lymphapheresis treatments have been performed without problems. The successful establishment of arteriovenous fistulas in nonuremic patients has been achieved by giving aspirin and low dose heparin therapy, which appears to be an integral step in maintaining patency.

Latent pulmonary embolus from a retroperitoneal sarcoma.

A 52-year-old female presented with an extensive retroperitoneal sarcoma and intraluminal inferior vena caval extension. Presumably during resection, embolization of a tumor fragment occurred to the right pulmonary hilum. The patient was asymptomatic for 16 months until a right hilar mass developed on a follow-up chest x-ray. Pathological examination of the gross and microscopic sections of the pneumonectomy specimen confirmed the intra-arterial location of the tumor mass. Widespread systemic metastasis became evident soon after pneumonectomy.

Diagnostic and therapeutic aspects of the surgical approach to Wegener's granulomatosis.

Over a 16 year period, 47 patients with Wegener's granulomatosis were treated at the National Institutes of Health. Age at the onset of disease ranged from 15 to 75 years with a mean of 42.2 years. The group was evenly divided between male and female subjects. With seven exceptions, all patients had the classic form of Wegener's granulomatosis, with upper airway and pulmonary disease and glomerulitis. The most consistently abnormal laboratory test was an elevated erythrocyte sedimentation rate. Most of the patients were treated with cyclophosphamide alone or in combination with prednisone. In 37 patients the disease now is well controlled or in complete remission from 1 to 9 years after the onset of symptoms. Of the 10 patients who died, only two were considered treatment failures. Forty-one of the 47 patients had chest x-ray changes at some point in their clinical course. Nineteen had bilateral involvement and 22 unilateral disease. Three of 11 patients with nodular disease had cavitation, and four of 21 with less discrete infiltrative disease demonstrated cavitation. Four patients had an associated pleural effusion and another four had pleural thickening. As part of the diagnostic procedure, 24 patients underwent an open lung biopsy. Two patients had a lobectomy for presumed neoplastic disease. In one patient the diagnosis of Wegener's granulomatosis was made by endobronchial biopsy. In the remaining patients the diagnosis was made by biopsy of another site. Endobronchial involvement is being seen with the increasing patient survival. Three patients had subglottic tracheal stenosis necessitating tracheal dilatations. One of the three also had multiple areas of bronchial stenosis responding to cyclophosphamide therapy. A fourth patient had progressive left main-stem bronchial stenosis which necessitated a sleeve resection. Five patients had pericarditis secondary to Wegener's granulomatosis.