Nitric oxide synthases are involved in the modulation of cardiovascular adaptation in hemorrhaged rats

AIM: Nitric oxide has been implicated in the cardiovascular adaptation to hemorrhagic shock. Our aim was to study the potential role of nitric oxide synthases (NOS) in the cardiovascular response in hemorrhagic hypotension produced experimentally in anesthetized rats. METHODS: Groups of animals (n = 14, per group): (a) normotensive; (b) hypovolemic (20% blood loss); (c) normotensive and pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME); (d) hypovolemic and pretreatment with L-NAME. RESULTS: L-NAME restored the hypotension induced by hemorrhage. Blood loss decreased heart rate in the first stage increasing at 60 and 120 min. L-NAME blunted this effect. Right atria and left ventricle histochemical NOS activities increased at 60 and 120 min (atria 8% and 24%, respectively; ventricle 21% and 45%, respectively). This activity increased 17% in smooth muscle at 120 min. Heart endothelial NOS protein levels increased in heart at 60 min being attenuated at 120 min. Inducible NOS protein levels raised significantly in right atria, left ventricle and aorta at 120 min. CONCLUSION: Hemorrhagic shock induced a time-dependent and specific NOS activation modulating cardiovascular function. The inhibition of nitric oxide system appears to prevent the acceleration of heart rate during late phases after acute hypovolemic state induced by blood loss.     

Massive Hemorrhage and Pseudo-Obstruction of the Small Intestine Caused by Primary AL Amyloidosis Associated with Gastric Cancer: Report of a Case

We report a case of AL amyloidosis in a patient diagnosed with early gastric cancer after presenting with massive gastrointestinal hemorrhage and pseud-oobstruction of the small intestine. Primary systemic amyloidosis accounts for 7% of nonhematological malignancies, but very few cases of gastric carcinoma in patients with primary amyloidosis have been described. We performed distal gastrectomy with biopsy of the small intestine in the absence of a diagnosis of systemic amyloidosis associated with early gastric cancer; however, the patient suffered severe postoperative complications secondary to the amyloidosis. Although acute pseudo-obstruction is an uncommon clinical manifestation of AL amyloidosis, the coexistence of both gastrointestinal hemorrhage ad pseudo-obstruction of the small intestine should alert the clinician to a diagnosis of gastrointestinal amyloidosis. We discuss the clinical manifestations of primary amyloidosis occurring in association with gastric cancer.     

Endovascular Therapy for Management of Oral Hemorrhage in Malignant Head and Neck Tumors

Purpose To evaluate the efficacy and safety of endovascular therapy in oral hemorrhage from malignant head and neck tumors. Methods Ten patients (mean age 56 years) with oral hemorrhage caused by malignant head and neck tumors underwent a total of 13 emergency embolization procedures using gelatin sponge particles, steel and/or platinum coils, or a combination of these embolic materials. Angiographic abnormalities, technical success rate, clinical success rate, recurrence rate, complications, hemostatic period, hospital days, survival days, and patient outcome were all analyzed. Results Angiographic abnormalities were identified during 85% of procedures (11/13). The technical success rate was 100% (13/13 procedures). The primary and secondary clinical success rates were 77% (10/13 procedures) and 67% (2/3 procedures), respectively. The overall clinical success rate was 92%, and the recurrence rate was 22% (2/9 procedures) in patients whom we were able to observe during the 1-month period after embolization. No major complications occurred. Several patients in whom gelatin sponge particles had been used complained of transient local pain after the procedure. The median hemostatic period was 71 days (range 0–518 days). Median hospital and survival days were 59 days (range 3–209 days) and 141 days (range 4–518 days), respectively. Three patients survived and 7 patients died during the observation period. Only 1 of these 7 patients died from hemorrhage. Conclusion In conclusion, our findings suggest that endovascular therapy is an effective, safe, and repeatable treatment for oral hemorrhage caused by malignant head and neck tumors.     

Cardiac output determination during experimental hemorrhage and resuscitation using a transesophageal Doppler monitor

Transesophageal Doppler (TED) monitoring has been considered a noninvasive and accurate alternative to pulmonary artery catheterization for volume replacement and cardiac output measurement in patients undergoing major surgery. This study tested the hypothesis that TED can accurately predict cardiac output during hemorrhage, shock, and resuscitation, by comparing it to total pulmonary artery blood flow (PABF) and to standard intermittent bolus cardiac output (ICO). In eight anesthetized dogs (18 +/- 1.0 kg), PABF was measured with an ultrasonic flowprobe while ICO and mixed venous O2 saturation (SvO2) were measured through a Swan-Ganz catheter. A TED probe (CardioQ, Deltex Medical Inc., Irving, TX, U.S.A.), designed for adult use (minimum 30 kg, 16 years), was placed in midesophageous to evaluate stroke volume. A graded hemorrhage (20 mL/min) was produced (H5-H35) to a mean arterial pressure (MAP) of 40 mm Hg and maintained by additional blood removal for 30 min (S1-S30). Total shed blood volume was retransfused (541 +/- 54.2 mL) over 30 min (T5-T30), after which a massive hemorrhage, 100 mL/min rate, was produced over 10 min (MH5-MH10). In general, TED overestimated PABF (r2 = 0.3472), but changes in TED paralleled PABF throughout the experimental protocol, particularly during massive hemorrhage (r2 = 0.9001). We concluded that TED accurately reflected the direction and magnitude of the changes of cardiac output over time during abrupt hemodynamic changes. Probes designed for lower weights and smaller aortas may improve its accuracy in medium size animal models under less dramatic alterations induced by hemorrhage, shock, and resuscitation.     

Changing Paradigms in Animal Models of Traumatic/Hemorrhagic Shock

Abstract To understand the complex network of pathophysiology after traumatic/hemorrhagic shock, mankind was particularly successful in using reductionistic approaches such as animal models to study the biology/physiology of normal states, to compare this with pathologic disease states and/or to follow the changes after modulation of pathologic states. One rationale for the study of animals is to discover and to develop effective therapies of traumatic/hemorrhagic shock that will lead to clinical testing in human patients. In this respect, three traditional traumatic/hemorrhagic shock models (uncontrolled bleeding, controlled fixed bleeding volume, and controlled decrements in blood pressure) are commonly applied, but must be critically reevaluated with regard to their clinical relevance under consideration of todays changing paradigms of knowledge on the pathophysiology of traumatic/hemorrhagic shock. Traumatic/hemorrhagic shock models with the endpoint of inadequate organ perfusion and tissue oxygenation mirror modern understandings of traumatic/hemorrhagic shock and seemed to be a solid basis for future investigations. Regarding this, the benefits of an oxygen debt shock model are discussed. With increasing knowledge in traumatic/hemorrhagic shock even further models may be necessary in the future.     

The magnetic resonance imaging of musculoskeletal hemorrhage

Hematomas in the extremities can present clinically as a soft tissue mass. Hematomas can usually be distinguished from neoplasia on MR by the signal patterns of hemoglobin breakdown products, which are dependent on the chemical bonding and oxidation state of hemoglobin iron. Beginning with a discussion of relevant atomic electronic structure, this review will examine how oxyhemoglobin, deoxyhemoglobin, methemoglobin, and hemosiderin, the principal iron compounds occurring in the various stages of a hematoma, affect its appearance on MRI. Received: 26 August 1999 Revision requested: 6 October 1999 Revision received: 27 October 1999 Accepted: 27 October 1999     

急诊介入治疗在出血病例中的临床应用

目的探讨急诊介入治疗在出血病例中的临床价值.方法对32例出血病例进行急诊血管造影,术中根据不同出血原因和部位分别再采用动脉栓塞或/和缩血管药物灌注治疗.结果动脉栓塞治疗28例,即时止血率为92.9%（26/28）,缩血管药物灌注治疗4例,即时止血率为50.0%（2/4）,本组总的即时止血率为87.5%（28/32）.结论各部位大出血在急诊血管造影的同时行动脉栓塞或缩血管药物灌注治疗是安全、有效的止血措施,具有非常重要的临床价值.     

过敏性紫癜合并消化道出血118例临床分析

过敏性紫癜是一种临床综合征，为与皮肤、胃肠道、类风湿病及肾小球等相关的系统性疾病。小儿多见，成年人发病率低但容易造成误诊，累及消化道时，出现呕血、黑便、便血、腹痛等症状。     

影响高血压脑出血微创手术治疗预后的相关因素分析

目的：探讨影响高血压脑出血微创手术病人预后的相关因素。方法：按手术后3个月的Barthel指数（BI）将128例高血压脑出血微创手术病人进行分组，70分以上（72例）为甲组，70分以下（56例）为乙组，通过对两组病人入院时的中国卒中量表（CSS）评分、手术时间、出血景、手术后的血压、血肿引流速度、并发症发生率（消化道出血、高热、水电解质紊乱）进行统计学分析，比较其相关性。结果：两组间术前诸多因素统计学分析差异无显著性，术后甲组血肿引流速度较快，术后36小时累计引出血肿75％以上达55例，占该组76．4％。血压稳定，并发症的发生率低，与乙组相比差异存在显著性（P〈0．05）。结论：影响高血压脑出血微创手术预后的关键因素是血肿引流速度恰当，血肿引流存在时间窗，如果能在术后36小时内将大部血肿引出，将避免和减轻灶周病理的产生和发展，减少并发症的发生率，对预后起关键作用。     

急性消化道大出血介入治疗的临床分析

目的 探讨介入治疗消化道大出血的价值。方法 10例消化道大出血患者中，8例为上消化道出血。其中6例经纤维内镜证实，2例根据临床表现确诊，均经内科保守治疗或内镜下止血无效者，采用介入治疗术，2例下消化道出血根据临床诊断。亦采用介入治疗。结果 10例消化道大出血患者均成功施行介入治疗术，即时止血率为100％。结论 介入治疗术是治疗消化道大出血的安全有效方法。