Emil Burihan

Hemodynamic improvement in hemorrhagic shock by aortic balloon occlusion and hypertonic saline solutions

The initial treatment of uncontrolled hemorrhage shock from an abdominal source is controversial. The hemodynamic effects of transfemoral diaphragmatic aortic occlusion with a balloon followed by a single bolus of hypertonic saline solutions have been evaluated in 28 dogs. The animals were submitted to pressure-driven hemorrhage for 90 min, according to mean arterial pressure in the abdominal aorta and randomized into four groups, according to the treatment employed at 34 min after hemorrhage. Group 1 dogs (controls) received isotonic NaCl (0.9%, 208 mOsm/l, 4 ml/kg) without aortic occlusion; group 2 underwent aortic occlusion and received isotonic NaCl (0.9%, 308 mOsm/l, 4 ml/kg): group 3 were occluded and received hypertonic NaCl (7.5%, 2400 mOsm/l, 4 ml/kg); group 4 were occluded and received hypertonic sodium acetate (10.5%, 2400 mOsm/l, 4 ml/kg). There were no significant differences between groups at basal measures and also after 30 min of continuous bleeding, when animals presented with severe shock, and significant decreases in mean arterial pressure, cardiac index, systolic index and cardiac filling pressures; the systemic vascular resistance index was increased. Control animals remained in severe shock throughout the experiment and three died. The recovery of mean arterial pressure in aortic-occluded dogs given isotonic NaCl was associated with a marked increase in systemic vascular resistance index, without improvements in cardiac index, systolic index and cardiac filling pressures. In occluded dogs given hypertonic NaCl and NaAc the mean arterial pressure recovery lasted longer, with lower increases in systemic vascular resistance index, while the cardiac index, systolic index and cardiac filling pressures showed a marked albeit transient increase. Injection of hypertonic saline following aortic occlusion produced significantly better hemodynamic profiles and should be seriously considered for the first treatment in severe uncontrolled hemorrhagic shock from an abdominal vascular source.

Traumatismos de veia cava inferior

BACKGROUND: Injuries of inferior vena cava (IVC) require immediate and definitive action. Our objective is to evaluate the incidence, the clinical findings and the operative approach to IVC injuries. METHODS: We retrospectively studied 76 patients with IVC injuries treated in two Emergency Hospitals of Manaus, AM, Brazil, from January 1997 to July 2002. Mechanisms of injuries, mortality, hemodynamic status, penetrating abdominal trauma index (PATI), intraoperative findings and surgical approach were among assessed data. RESULTS: Fourty-nine patients (65%) had stab wounds, 26 (34%) gunshot wounds, and one had blunt abdominal trauma. Fourty-one (54%) patients survived. Almost all patients entered the emergency room awake, although 40% were hypotensive (systolic blood pressure < 70 mmHg), and the penetrating abdominal trauma index average was above 40. At laparotomy, active retroperitoneal bleeding or an expanding retroperitoneal hematoma were detected in all cases. Caval injury was retro-hepatic in 21 patients, and infrahepatic in the other 55. The prevailing surgical approach was lateral repair in 65 patients. Atrial-caval shunting was tried in six patients, with only three survivals. CONCLUSIONS: We concluded that IVC injury remains a highly lethal injury and there is a close relationship with urban violence. This study emphasizes that successful outcome depends on prompt volume restoration, avoidance of hypothermia and a stratified selective surgical approach.

Ligation of the left renal vein in epm1-wistar rats: functional and morphologic alterations in the kidneys, testes and suprarenal glands

OBJECTIVE The ligation of the left renal vein (LLVR) in man is a controversial procedure in view of the risks of lesion to the renal parenchyma. With the objective of studying the morphologic and functional alterations caused by these lesions, we conducted experimental research with rats. MATERIAL AND METHODS 64 male adult EPM1-WISTAR rats were used, divided into 8 groups-4 for LLRV and four for control. Each LLRV group and corresponding control group were sacrificed progressively on the 7th, 15th, 30th and 60th day after the initial surgery. RESULTS We found morphofunctional alterations only in animals that underwent LLRV in the four periods of sacrifice. The proteinuria creatinine in serum, testosterone in serum and serum corticosterone in serum showed practically no alteration in relation to the normal values for rats. Statistically significant severe histological lesions were found in the kidneys and testes of the LLRV groups. Lesions in the suprarenal glands were also present in these groups, but no sufficient to demonstrate statistical significance. CONCLUSION Based on these results we can conclude that the ligation of the left renal vein is a procedure of high risk in these animals.

Percutaneous transluminal angioplasty in the treatment of renovascular hypertension: sequential prospective study

OBJECTIVE To evaluate the use of percutaneous transluminal renal angioplasty (PTRA) in the treatment of renal vascular hypertension. DESIGN Sequential prospective PTRA treatment of severe arterial hypertension, screening by the captopril test, confirmed by renal arteriography, and the result evaluated by post-PTRA arteriography, blood pressure measurement and renal function. SITE: Vascular Surgery, angioradiology sector, and Nephrology outpatients department of the Federal University of São Paulo-Paulista School of Medicine, São Paulo, Brazil, a tertiary health-care institution. PARTICIPANTS PTRA was employed on 32 patients screened by clinical examination, captopril test and renal arteriography. EVALUATION PTRA results were evaluated by the criteria of the Cooperative Study of Renovascular Hypertension. RESULTS After PTRA the completion arteriography showed no renal stenosis in 24 patients (75%), residual stenosis (20-50%) in 3 (9.4%) and no change in 5 (15.6%). The blood pressure results were: 3 patients (9.4%) were cured, 24 (75%) improved and 5 (15.6%) were unchanged. We observed normal renal function before and after PTRA in 25 patients (78%); altered pre- and improved post-PTRA in 2 (6.3%); post-PTRA remained unaltered in 2 (6.3%); and altered pre- and worsened post-PTRA in 3 (9.4%). Recurrence of stenosis occurred in one patient after 8 months. CONCLUSIONS PTRA is a convenient procedure, relatively safe and an effective complementary method of medical therapy for controlling renovascular hypertension.

Avaliação do fluxo arterial mesentérico em humanos durante o exercício

Mesenteric artery blood flow was measured by Doppler ultrasound in eight healthy subjects (age 21-26 years, mean=25.8) submitted to incremental exercise. As cardiovascular responses change above the point at which blood lactate starts to accumulate, a protocol was designed to determine the velocity profile and mesenteric artery flow redistribution along incremental exercise. On the first part of the protocol all individuals were submitted to determinations of lactate thresholds by the enzimatic method modified by Ribeiro et al (1986). On the second test mesenteric artery blood flow and sistolic, reverse and diastolic velocities were measured at rest and immediately after 30 Watts, first lactate threshold, second lactate threshold and at peak exercise. In this way exercise intensities were adjusted for each individual independently of training and physical conditions. Total mesenteric artery blood flow was calculated using planimetric measurement of the velocities waves and area determinations. The Friedman test was used to analise de data. There was no significant change of sistolic velocities during incremental exercise. In the other hand there was a marked decrease of diastolic velocities; a linear decrease of initial diastolic velocities and an abrupt decrease of end-diastolic velocities after the first lactate threshold. At peak exercise a redution of 77% in end-diastolic velocities was observed. A linear reduction of mesenteric artery blood flow was observed and there was no correlation with lactate thresholds; at peak exercise a decrease of 34% was detected. Resting mesenteric blood flow was 1.034± 112 (SE), at 30 Watts 1.002± 124 (SE), at the first lactate threshold 869± 122 (SE), at the second lactate threshold 866± 127 (SE) and at peak exercise 689± 104 (SE).