Hypertension and vulnerability to hemorrhagic shock in a rat model.

Trauma mortality may be increased in the presence of preexisting diseases such as chronic hypertension. We hypothesized that systemic and microvascular alterations accompanying chronic hypertension would increase the vulnerability to hemorrhage relative to normotensive controls in a rat model of hemorrhagic shock. We present a novel comparative hemorrhage model of shock vulnerability, quantified by "vulnerability curves" expressing physiological response to hemorrhage as a function of three matched shock metrics: cumulative blood volume, mean arterial pressure (MAP), and oxygen delivery (Do2). Responses were central hemodynamics and respiratory and muscle oxygenation obtained for one hypertensive (spontaneously hypertensive [SHR]) and two normotensive (Sprague-Dawley, Wistar-Kyoto) rat strains. Hemorrhagic shock was induced by incremental (0.5 mL) hemorrhage to cardiovascular collapse in anesthetized and mechanically ventilated animals. Shock vulnerability of SHR rats was primarily pressure-driven; in general, SHR exhibited the expected patterns of more rapid deterioration in MAP and Vo2 over smaller ranges of blood loss and Do2. Sternotomy-related depression of CO and thus Do2 in SHR meant that we could not test hypotheses related to the role of Do2 and contribution to perfusion differences between normotensive and hypertensive subjects. Insensitivity of lactate to strain effects suggests that lactate may be a reliable biomarker of shock status. Unexpected similarities between Wistar-Kyoto and SHR suggest strain-related effects other than those related to hypertension per se contribute to hemorrhage response; body size effects and genetic relationships could not be ruled out. Future studies should incorporate phylogenetically based methods to examine the role of hypertension and physiological response to hemorrhage across multiple strains.

Primary cutaneous zygomycosis in an immunodeficient infant: a case report and review of the literature.

We report a case of primary cutaneous zygomycosis caused by Rhizopus species in an infant with a hematological malignancy. Multiple surgical debridements, skin grafting, and intravenous antifungal therapy were necessary to ultimately eradicate the infection. Zygomycotic infections are an emerging concern in immunocompromised patients because of their increased incidence as well as their potential to cause substantial morbidity through both emotional distress and impaired functionality. Because resection is a cornerstone of treatment for zygomycosis, the authors anticipate a growing need for plastic surgery involvement for both surgical debridement with limb and tissue-sparing procedures, and for reconstructive options that effectively treat the disease while preserving both function and esthetics. The plastic surgery literature is reviewed regarding surgical and reconstructive options for this population of patients. This case demonstrates the important role plastic surgeons play in the multidisciplinary treatment of zygomycotic and other opportunistic cutaneous infections.

Surgical treatment of mild hallux valgus deformity: the state of practice among academic foot and ankle surgeons.

BACKGROUND: The purpose of this study was to determine the operative procedure of choice among academic foot and ankle surgeons practicing in the United States for treatment of mild hallux valgus deformity. METHODS: A hypothetical patient was created: a 60-year-old woman with a mild hallux valgus deformity (first intermetatarsal angle of 11 degrees and hallux valgus angle of 22 degrees). The patient complained of pain around the bunion, nonoperative treatment had failed, and she desired operative correction. The case was sent to academic foot and ankle surgeons to identify their operative treatment of choice. The overall response rate was 83.7% (128 of 153). To be included in the study group each surgeon had 1) foot and ankle patients comprising 50% or more of their clinical practice and 2) direct responsibility for teaching orthopaedic surgery residents. One hundred and three respondents met the inclusion criteria and formed the study group. RESULTS: Eighty-seven percent (90 of 103) reported that they would use a distal chevron osteotomy as their primary procedure to correct the mild hallux valgus. Ten percent (10 of 103) reported that they would also add an Akin osteotomy of the proximal phalanx to enhance correction. CONCLUSIONS: Most respondents chose a distal chevron osteotomy as their primary procedure to correct the mild hallux valgus deformity.

Surgical treatment of severe hallux valgus: the state of practice among academic foot and ankle surgeons.

BACKGROUND: The purpose of this study was to evaluate the operative procedures used for treatment of severe hallux valgus by academic foot and ankle surgeons practicing in the United States. METHODS: A patient with severe hallux valgus deformity was developed as a hypothetical case: a 50-year-old woman with a severe deformity (intermetatarsal angle = 20 degrees; hallux valgus angle = 42 degrees). The patient was symptomatic with pain, did not improve with conservative measures, and wanted the deformity corrected. This case was sent to academic foot and ankle surgeons in a survey to determine their preferred operative treatment for this case. The overall response rate was 84% (128 of 153). To be included in the study group each surgeon had to have 1) foot and ankle patients comprising 50% or more of his clinical practice and 2) direct responsibility for teaching orthopaedic residents. One hundred and five respondents met the inclusion criteria and formed the study group; however, three surveys with invalid responses were deleted. RESULTS: Fifty-two percent (54 of 102) of the respondents chose a metatarsal osteotomy, 26% (26 of 102) a first metatarsophalangeal (MTP) joint arthrodesis, and 24% (24 of 102) a Lapidus procedure. Two respondents chose both an arthrodesis and a metatarsal osteotomy. Among the 54 respondents who chose metatarsal osteotomies, 24 used a Ludloff, 16 a proximal crescentic, eight a proximal chevron, two a scarf, two a distal chevron, and two other. In addition, secondary procedures to enhance the correction included a Weil osteotomy in 46% (47 of 102) and an Akin osteotomy in 30% (31 of 102). CONCLUSIONS: There was a wide variation in the type of procedure used to correct this severe hallux valgus deformity; approximately 50% of the respondents chose a metatarsal osteotomy, 25% chose a first MTP joint arthrodesis, and 25% a Lapidus procedure.

B cell reductive therapy in the treatment of autoimmune diseases: a focus on monoclonal antibody treatment of rheumatoid arthritis.

The therapeutic approach to patients with autoimmune disorders is in the midst of a dramatic change. Monoclonal antibody technology has allowed us to dissect and now manipulate the human immune system with greater precision. It is now widely recognized that B lymphocytes play a role in the pathogenesis of many autoimmune diseases, though the extent and contribution is a matter of debate and active investigation. There is emerging data to suggest that both antibody-dependent and independent mechanisms contribute to disease pathogenesis. However, given the heterogeneous nature of autoimmune diseases, and the varied responses to B lymphocyte reduction, the role of B lymphocytes is likely disease-specific. The two clinical trials discussed in this review demonstrate remarkable consistency in the ability of B cell reduction to ameliorate the clinical manifestations of rheumatoid arthritis with minimal toxicity. B lymphocyte targeted approaches to autoimmune disease in general, and RA specifically, will not only provide an effective and potentially less toxic alternative treatment option, but also allow for a better understanding of the pathogenesis of these complex and morbid diseases.