1/4. Colonic perforation following prolonged hypovolaemia in a major burns injury.Perforation of the lower gastrointestinal tract is rare in burns patients. A 41-year-old male, who sustained 40% total body surface area burns and subsequently developed an acute abdomen on day 15 postburn, is presented. Emergency management included a subtotal colectomy and ileostomy formation performed to repair a perforated transverse colon found at laparotomy. The burns were debrided and grafted and the patient required cardiac, renal and respiratory support initially in the ITU setting before making a complete recovery. It is suggested that ischaemia caused the perforated transverse colon due to a prolonged low flow state. This was not detected until invasive cardiovascular catheterisation was performed and revealed a hypovolaemic state, which was corrected by fluids and noradrenaline. Both the previous cardiac history of the patient (Fallot's Tetralogy repair) and the noradrenaline may have exacerbated the low flow state within the mesenteric circulation leading to ultimate perforation. This case highlights the difficulties that may arise in resuscitating a patient who has previously had a cardiac defect repaired. Despite repair, abnormal physiology may persist resulting in misleading observations that produce undetected hypovolaemia with subsequent adverse events, as in this case. In such patients, early invasive cardiovascular monitoring should be considered.- - - - - - - - - - ranking = 1keywords = ischaemia (Clic here for more details about this article) |
2/4. Sudden blindness caused by anterior ischemic optic neuropathy in 5 children on continuous peritoneal dialysis.The authors report the occurrence of sudden blindness in 5 children (mean age, 32 months; range, 11 to 60) during continuous peritoneal dialysis regimen. All children presented with loss of light perception, visual fixation and ocular pursuit, and bilateral mydriasis unreactive to bright light. Fundoscopic examination found signs of anterior ischemic optic neuropathy with disc swelling, edema, and hemorrhages. Whereas 1 patient was dehydrated, the 4 other patients appeared well and not dehydrated. Nevertheless, blood pressure was below the normal range in all of them. Therefore, hypovolemia is highly suspected to have been the cause of ischemic optic neuropathy in all cases. Treatment consisted of steroids (4 patients), anticoagulation or antiagregation drugs (3 patients), plasma or macromolecules infusions (2 patients), vasodilatators (2 patients), and transient dialysis interruption (1 patient). One child with hepatic cirrhosis died 4 days later of acute liver insufficiency owing to ischemic hepatic necrosis. The other children had only partial improvement of vision during the following months. Because the prognosis of ischemic optic neuropathy is very poor, diagnosis and treatment of chronic hypovolemia in children on continuous peritoneal dialysis is essential to prevent such a devastating complication.- - - - - - - - - - ranking = 1077767.3488697keywords = ischemic optic neuropathy, ischemic optic, anterior ischemic optic neuropathy, optic neuropathy, anterior ischemic optic, optic, neuropathy (Clic here for more details about this article) |
3/4. Hypovolemic ischemic optic neuropathy.BACKGROUND: Ischemic optic neuropathy refers to an acute event of ischemia, or decreased blood flow, to the optic nerve resulting in varying degrees of vision loss and visual field defects. Typically this disease affects the elderly population who experience systemic diseases that compromise the blood flow efficiency of the optic nerve head (e.g., giant-cell arteritis, hypertension, diabetes, etc.). However, cases of blood loss to the optic nerve, secondary to traumatic injuries or surgeries, have also been shown to result in ischemic optic neuropathy, regardless of age. It seems that in these cases, the resulting anemia and hypotension play contributing roles in the development of ischemic optic neuropathy. methods: A 41-year-old black man came to us with optic nerve head pallor O.S., count-fingers vision O.S., positive afferent pupillary defect O.S., and a central scotoma O.S. after being hospitalized and treated for a stab wound to his left neck that severed his left carotid artery at the bifurcation. RESULTS: This patient had been seen in the optometry Clinic two years before the stab-wound incident. At that time, he had 20/20 vision in his left eye and no remarkable neurological deficits. His ocular presentation after the traumatic hypovolemic event was probably a direct result of the hypoperfusion to the left optic nerve head. This patient was diagnosed with a hypovolemic, or blood loss-related, ischemic optic neuropathy (O.S.). CONCLUSIONS: patients who experience large amounts of blood loss due to trauma, surgery, internal bleeding, etc. and report vision loss should be screened for possible optic nerve ischemia. As eye care providers, when we are presented with patients who have optic nerve head atrophy, we should inquire about events that may have precipitated blood loss, potentially triggering ischemic optic neuropathy.- - - - - - - - - - ranking = 1173273.183723keywords = ischemic optic neuropathy, ischemic optic, optic neuropathy, optic, neuropathy (Clic here for more details about this article) |
4/4. On-line optical sensing of blood volume changes to prevent intradialytic hypovolemia.Intradialytic hypovolemia is a common complication of hemodialysis treatments. blood volume changes that occur during dialysis can be followed by on-line optical sensing of the patient's hematocrit. Characteristic curves of blood volume changes can be seen in fluid overloaded patients with symptoms of hypovolemia, i.e. cramps, hypotension. The relative blood volume changes in those who have fluid removed to their ideal "dry" weight without symptoms will be shown in comparison. As Phase I of a CQI project, the nephrologist and dialysis nurses at the london health Sciences Centre performed a cross-sectional study to define the frequency of these curves and their relationship to intradialytic symptoms. The analysis of these curves can be used to re-assess "dry" weights, prevent intradialytic hypovolemia and decrease the use of antihypertensive agents. The correlation of our findings with the results of an independent hypotensive CQI study will be presented.- - - - - - - - - - ranking = 470.15521336647keywords = optic (Clic here for more details about this article) |