Glucocorticoid inhibition of neuropathic limb edema and cutaneous neurogenic extravasation

Sciatic nerve section in rats evokes chronic limb edema, pain behavior, and hindpaw hyperalgesia, a syndrome resembling the complex regional pain syndrome type II (CRPS II or causalgia) in man. Glucocorticoids such as methylprednisolone (MP) have been used as analgesic and anti-edematous agents in patients suffering from CRPS, and interestingly these therapeutic effects appear to persist in some patients after stopping the medication. Similar to the CRPS clinical response to glucocorticoids, we now demonstrate that chronic hindpaw edema in the sciatic transection CRPS model is reversed by a continuous infusion of MP (3 mg/kg/day over 21 days), and this anti-edematous effect persists for at least 1 week after discontinuing MP. Furthermore, there is a chronic increase in spontaneous protein extravasation in the hindpaw skin of rats after sciatic transection, similar to the increased protein extravasation observed in the edematous hands of CRPS patients. A 2-week infusion of MP (3 mg/kg/day) reduced spontaneous protein extravasation in the hindpaw skin by 80%. We postulated that increased spontaneous neurogenic extravasation resulted in development of limb edema in both the animal model and the CRPS patient, and that the anti-edematous effects of MP are due to an inhibition of spontaneous extravasation. Additional experiments examined the inhibitory effects of MP infusion on electrically-evoked neurogenic extravasation in the hindpaw skin of normal rats. MP inhibition was dose- and time-dependent, with an ED₅₀ of 1.2 mg/kg/day for a 14-day continuous infusion of MP, and a maximum inhibitory effect requiring 17 days of MP infusion (3 mg/kg/day). MP (3 mg/kg/day for 14 days) also blocked both capsaicin- and SP-evoked neurogenic extravasation, indicating a post-junctional inhibitory effect. Our interpretation is that increased spontaneous neurogenic extravasation in this CRPS model contributed to the development and maintenance of hindpaw edema, and that chronic MP administration dose- and time-dependently blocked neurogenic extravasation at a post-junctional level, thus reversing spontaneous extravasation and limb edema in this model.     

MR imaging of edematous anconeus epitrochlearis: another cause of medial elbow pain?

Two patients with unusual medial elbow pain had MRI scans performed that revealed edema of the aberrant muscle of the anconeus epitrochlearis. MRI of this anconeus epitrochlearis muscle are presented.     

Transient edema of the spinal cord as a result of spontaneous acute epidural hematoma in the thoracic spine

We present an unusual case of spontaneous epidural hemorrhage in the thoracic spine resulting in rapid onset of transient and extensive edema in the spinal cord. The patient presented with acute onset of midscapular back pain, bilateral lower extremity weakness, and bladder dysfunction. Repeat MRI 20 days after decompression of the hematoma showed residual hematoma and complete resolution of the spinal cord edema. The implications and differential diagnosis of spinal cord edema in this clinical setting are discussed.     

Alpha1-acid-glycoprotein protects against trauma-hemorrhagic shock

BACKGROUND: Recent studies have shown that the acute phase protein alpha(1)-acid-glycoprotein (AAG) directly modifies endothelial cell responsiveness and is a crucial factor for maintaining endothelial barrier function. We hypothesized that the addition of AAG to the resuscitation fluid will prevent edema formation, increases circulating blood volume, and reduces tissue inflammation following soft tissue trauma and hemorrhagic shock. MATERIALS AND METHODS: Male Sprague-Dawley rats (338 +/- 28 g) underwent a 5-cm midline laparotomy (i.e., induction of soft tissue trauma) and were bled to and maintained at a mean arterial pressure of 35 mm Hg for 90 min. The rats were then resuscitated with four times the shed blood volume with Ringer's lactate containing 200 mg/kg AAG or the same amount of albumin. At 6 h after resuscitation, organ wet-to-dry weight ratios and circulating blood volume (Evans blue dilution) were determined. Neutrophil accumulation (myeloperoxidase activity, MPO) and tissue lipid peroxidation (thiobarbituric acid reactive substances) were also measured in the lungs, liver, and intestine. RESULTS: Administration of AAG during the resuscitation significantly increased circulating blood volume and reduced edema formation, neutrophil accumulation, and lipid peroxidation. Interestingly, concomitant plasma IL-6 levels increased while TNF-alpha levels were not significantly affected. CONCLUSIONS: Since addition of AAG to the resuscitation fluid increased circulating blood volume, reduced edema formation, and neutrophil accumulation following trauma and hemorrhagic shock, supplementation of this acute phase protein appears to be a potential adjunct to prevent capillary leakage in patients undergoing major traumatic injury.     

Obstructive symptoms associated with the Lap-Band in the first 24 hours

Background: The Lap-Band is a gastric restrictive procedure for the treatment of morbid obesity. We review the etiology of obstructive complications that present in the first postoperative 24 h. Methods: Fifty-six Lap-Band procedures were performed by one surgeon between January and September 2002. Results: Six patients presented with obstruction within 24 h of surgery: gastric slippage in three patients, gastric edema in one patient, and esophageal hypomotility in two patients. Conclusions: Placing the band in an esophagogastric position as per Belachew and Weiner reduced our incidence of gastric slippage to none. Endoscopy with placement of a nasogastric feeding tube can relieve obstruction caused by esophageal hypomotility. Gastric edema with no clinical signs of obstruction will resolve with time. Clinicians must be aware of the unique complications that come with the advent of this new procedure.     

Idiopathic edema is associated with obstructive sleep apnea in women

BACKGROUND AND PURPOSE: This study was undertaken to clarify whether idiopathic edema is a marker for obstructive sleep apnea (OSA), independent of level of obesity, in patients with normal left ventricular function. PATIENTS AND METHODS: Seventy-eight ambulatory, obese, adults, 44 with bilateral, pitting pre-tibial edema, and 34 without edema, from an inner city family practice and a suburban family practice enrolled from July 1995 until March 2003. Edematous subjects, but not non-edematous subjects, underwent echocardiography, urinalysis, and blood test evaluations to ensure that cardiac, renal, hepatic, and thyroid functions were normal. All subjects underwent spirometry, pulse oximetry on room air, and polysomnography evaluations. RESULTS: Compared to the non-edematous subjects, the edematous subjects were more obese (body mass index=47.0+/-9.3 versus 36.5+/-4.6 kg/m2, P=0.002), had more severe OSA (apnea-hypopnea index (AHI)=34.1+/-27.7 versus 17.0+/-19.4, P=0.002), and had lower oxygen saturations (96.2+/-2.0 versus 97.1+/-1.5%, P=0.05). Using an AHI > or = 15 as the criteria for diagnosing OSA, there was an association between edema and OSA in women (P=0.02) but not men. CONCLUSIONS: In subjects with normal left ventricular function, idiopathic edema is associated with OSA in women.     

Acute peritoneal dialysis as both cause and treatment of hypernatremia in an infant

This report describes a 4-month-old infant with multisystem organ failure who developed severe hypernatremia (sodium 168 mEq/l) due to rapid free water removal associated with acute peritoneal dialysis instituted for fluid overload. The current report describes the pathophysiology of the hypernatremia, and its correction by low-sodium hypertonic peritoneal dialysis without compromising ultrafiltration or supplementing with free water. Although peritoneal dialysis can cause hypernatremia, a modified solute concentration in the dialysate can treat the hypernatremia successfully. Received: 2 January 2001 / Revised: 24 April 2001 / Accepted: 24 April 2001     

连续性血液净化治疗重症急性胰腺炎的临床分析

目的 探索连续性血液净化（CRRT）对重症急性胰腺炎（SAP）的治疗作用，提高重症急性胰腺炎的抢救成功率。方法 选择15例SAP患者给予CRRT治疗，观察治疗前、后患者血液生化指标、血常规、血气分析，并进行动态急性生理学及慢性健康状况评分（APACHEII）、简化急性生理学评分（SAPSII）和多脏器功能障碍综合征（MODS）评分。结果 与治疗前相比，CRRT治疗第2日晨和CRRT治疗结束后次日晨患者APACHEII、SAPSII和MODS评分比治疗前降低，治疗后氧合指数（PO2/FiO2）有明显改善。CRRT治疗次日晨PO2/FiO2和CRRT脱水量呈正相关；CRRT治疗第2日晨，脱水量与MODS评分呈负相关。CRRT治疗过程中血BUN、Cr和尿酸均降低，治疗时间越长，降低越明显。结论 CRRT治疗后心、肺功能的改善与脱水后组织器官间质水肿减轻有关，但并非脱水越多越好。从清除BUN、Cr来看，CRRT治疗时间似乎越长越好；但对BUN、Cr正常的患者，治疗时间可以缩短。连续性血液净化能改善、维持重症胰腺炎患者心、肺、肾、脑等重要脏器功能，提高其抢救成功率，对重症急性胰腺炎有较好的治疗作用。     

Edema vulvar masivo en preeclampsia severa

We report the case of a pregnant woman with pregestational diabetes who developed severe preeclampsia in week 22 of pregnancy culminating in acute massive edema of the vulva and acute edema of the lung. A Medline search was performed to identify published studies related to this topic. Acute vulvar edema in pregnancy can be predictive of serious complications and consequently intense monitoring is mandatory. In our patient, Cesarean delivery was performed at week 26, due to serious maternal complications.     

Physiological importance of aquaporin water channels

Aquaporins (AQP) are a family of at least ten homologous water transporting proteins in mammals that are expressed in many epithelial, endothelial and other tissues. Abnormalities in humans and mice lacking AQPs provide direct evidence for their physiological importance. Humans lacking AQP1 or AQP2 manifest polyuria with defective urinary concentrating ability and humans with mutations in MIP (AQP0) develop cataracts. Transgenic knockout mice lacking AQP1 or AQP3 are also remarkably polyuric, and knock-in mice expressing a mutant AQP2 have severe nephrogenic diabetes insipidus resulting in impaired neonatal survival. Other interesting phenotypes in AQP knockout mice include reduced pain sensation, reduced intraocular pressure, defective corneal fluid transport and impaired dietary fat processing (AQP1), dry skin (AQP3), protection from brain swelling and impaired hearing/vision (AQP4), and reduced fluid secretion by salivary and airway submucosal glands (AQP5). However, many phenotype studies were negative, such as normal airway/lung and skeletal muscle function despite AQP expression, indicating that tissue-specific aquaporin expression does not indicate physiological significance. The general paradigm from studies on transgenic mouse models of AQP deletion is that AQPs facilitate rapid near-isosmolar transepithelial fluid absorption/secretion, as well as rapid vectorial water movement driven by osmotic gradients. The transgenic mouse studies suggest that aquaporin inhibitors may have clinical indications as diuretics and in the treatment of cerebral edema, elevated intraocular pressure, and other conditions of abnormal fluid homeostasis.