Persistent Hemodynamic Instability Research Articles

Control of severe hemorrhage using C-clamp and arterial embolization in hemodynamically unstable patients with pelvic ring disruption

Hemorrhage is the leading cause of death in patients with a pelvic fracture. The majority of blood loss derives from injured retroperitoneal veins and broad cancellous bone surfaces. The emergency management of multiply injured patients with pelvic ring disruption and severe hemorrhage remains controversial. Although it is well accepted that the displaced pelvic ring injury must be rapidly reduced and stabilized, the methods by which control of hemorrhagic shock is achieved remain under discussion. It has been proposed to exclusively use external pelvic ring stabilization for control of hemorrhage by producing a 'tamponade effect' of the pelvis. However, the frequency of clinically important arterial bleeding after external fixation of the pelvic ring remains unclear. We therefore undertook this retrospective review to attempt to answer this one important question: How frequently is arterial embolization necessary to control hemorrhage and restore hemodynamic stability after external pelvic ring fixation? We performed a retrospective review of 55 consecutive patients who presented with unstable types B and C pelvic ring fractures. Those patients designated as being in hemorrhagic shock (defined as a systolic blood pressure less than 90 mmHg after receiving 2 L of intravenous crystalloid) were treated by application of the pelvic C-clamp. Patients who remained in hemorrhagic shock, or were determined to be in severe shock (defined as mandatory catecholamines or more than 12 blood transfusions over 2 h), underwent therapeutic angiography within 24 h in order to control bleeding. Fourteen patients were identified as being hemodynamically unstable (ISS 30.1 +/- 11.3 points) and were treated with a C-clamp. In those patients with persistent hemodynamic instability, arterial embolization was performed. After C-clamp application, 5 of 14 patients required therapeutic angiography to control bleeding. Two patients died, one from multiple sources of bleeding and the other from an open pelvic fracture (total mortality 2/14, 14%). Although the C-clamp is effective in controlling hemorrhage, one must be aware of the need for arterial embolization to restore hemodynamic stability in a select subgroup of patients.

The Role of Transesophageal Echocardiography in Optimizing Resuscitation in Acutely Injured Patients

The goal of resuscitation is to correct the mismatch between oxygen delivery and that of cellular demands. The pulmonary artery catheter (PAC) is frequently used to gauge the adequacy of resuscitation and guide therapy based on ventricular filling pressures. Transesophageal echocardiography (TEE) has emerged as a potential tool in assessing adequacy of acute hemodynamic resuscitation. The purpose of this study was to evaluate the role of TEE in assessing preload during ongoing volume resuscitation in trauma patients. A retrospective review was conducted of acutely injured patients undergoing TEE during resuscitation from hemorrhagic shock from January 2002 to 2004 at a Level I trauma center. The indication for TEE was persistent hemodynamic instability in the absence of ongoing surgical hemorrhage. Variables included hemodynamic and PAC parameters, pre-TEE resuscitation volume, and vasopressor requirements. The impact of TEE findings on therapeutic decisions was evaluated. Twenty-five patients underwent TEE, 18 (72%) had an indwelling PAC with a mean pulmonary artery occlusion pressure of 19.3 mm Hg (range, 12-29 mm Hg) and mean cardiac index of 2.9 L/min/m2 (range, 1.6-4.6 L/min/m2). Twelve patients (48%) were receiving inotropes and/or vasopressors for hypotension at the time of TEE. Resuscitation volume within 6 hours before TEE included a mean of 6.5 L of crystalloid and 12.2 units of blood products (packed red blood cells, fresh frozen plasma, and platelets). TEE revealed left ventricular hypovolemia in 13 patients (52%) and altered therapy in 16 patients (64%), including additional volume (n = 13), addition of an inotrope (n = 4), and addition of a vasodilator (n = 1) in one patient with ventricular overdistention. Comparison of the abnormal and normal TEE groups revealed that only cardiac index was significantly different (2.6 L/min/m2 in the abnormal group vs. 3.9 L/min/m2 in the normal group; p = 0.005). Significant mitral valve regurgitation leading to valve replacement was identified in one patient. No clinically relevant pericardial effusion was identified. TEE altered resuscitation management in almost two thirds of patients. Many patients with "acceptable" pulmonary artery occlusion pressure parameters may in fact have inadequate left ventricular filling. In addition, TEE offers the advantage of direct assessment of cardiac valve competency, myocardial wall contractility, and pericardial fluid.

Laparoscopy in penetrating abdominal trauma

BACKGROUND: Penetrating abdominal trauma (PAT) poses a significant challenge to trauma surgeons. There is no doubt that persistent hemodynamic instability or signs of peritoneal irritation warrant immediate laparotomy. If the patient is hemodynamically stable and has equivocal abdominal examination findings, diagnosis may be obtained by laparoscopy. METHODS: The goal of this article is to evaluate the role of laparoscopy in the management of PAT. RESULTS: Patients with penetrating trauma to the thoracoabdominal and anterior abdominal wall are good candidates for laparoscopic evaluation. The peritoneal cavity and its contents, including the retroperitoneal space, can be thoroughly examined easily and safely. The main benefits of laparoscopy include the reduction of nontherapeutic laparotomies, identification of mostly intra-abdominal injury, and provision of potential therapy for some cases. Diagnostic laparoscopy has a high overall diagnostic accuracy, reduced morbidity, and shortened hospital stay and is also cost-effective. While laparoscopy has some limitations in the diagnosis of hollow viscus injury, it can detect and repair diaphragmatic injuries accurately and exclude the risk of nontherapeutic laparotomy due to a nonbleeding injury of the solid organs. CONCLUSIONS: The use of laparoscopy as a diagnostic or therapeutic method in patients with PAT is reserved only for hemodynamically stable patients and uncertain findings of peritonitis. Laparoscopy is an efficient and effective diagnostic tool when used by a well-trained surgeon. With experience, an increasing number of surgeons are using laparoscopy as an additional diagnostic tool for PAT in stable patients. With more experience and skills, laparoscopy may be used more therapeutically in selected patients. Minimally invasive surgery has already established itself as a useful tool in the management of PAT. The future seems to be promising for this field of surgery by innovative developments in computer technology and robotic systems.

Endovascular treatment of a massive retroperitoneal bleeding: Successful balloon-catheter delivery of intra-arterial thrombin

Retroperitoneal bleeding is a potentially lethal complication of percutaneous intervention, when the common femoral artery is used as vascular access. Surgery, the traditional treatment for this complication in patients with persistent bleeding or hemodynamic instability, carries a considerable risk of morbidity and mortality. We report a case of life-threatening retroperitoneal bleeding successfully treated percutaneously with balloon occlusion and catheter delivery of thrombin to attain thrombosis of a lacerated branch of the common femoral artery. Endovascular catheter-based percutaneous treatment for massive retroperitoneal bleeding is often effective and should be pursued in selected patients.

Conduite à tenir devant un hématome rétro-péritonéal d’origine traumatique

Traumatic retroperitoneal hematoma (RPH) may arise from injury to bony structures, major blood vessels, and intestinal or retroperitoneal viscera. To categorize the management of RPH, the retroperitoneum may be divided into three zones. Zone 1 (central) extends from the esophageal hiatus to the sacral promontory. Zone 2 (lateral) extends from the lateral diaphragm to the iliac crest. Zone 3 (pelvic) is confined to the retroperitoneal space of the pelvic bowl. For the traumatized patient with RPH, laparotomy is mandated by persistent hemodynamic instability despite intensive volume replacement. The judgment of whether and when to explore the retroperitoneal hematoma is guided by the mechanism of injury (blunt or penetrating) and the location of the RPH. RPH localized to the upper central area (Zone 1) after penetrating trauma implies injury to the great vessels and always requires urgent surgical exploration. RPH in other zones should be evaluated by CT and/or angiography; ongoing hemorrhage may respond to therapeutic embolization.

Management of Major Blunt Renal Lacerations: Is a Nonoperative Approach Indicated?

Objectives: The aim of the study was to determine whether a nonoperative approach is able to reduce renal parenchymal loss after renal trauma. Methods: Sixty–four consecutive patients with major blunt renal lacerations were treated from 1988 to 1999. Initial management was conservative. In group 1 (35 patients) delayed hemorrhage, persistent urinoma or hemodynamic instability were dealt with by open surgery. In group 2 (29 patients), most complications were dealt with using endoscopic procedures; open surgery was reserved exclusively for major complications. Results: In group 1, 7 patients were not operated and 28 patients were managed surgically. Twenty (57%) patients underwent total (8) or partial (12) nephrectomy. In 8 patients the surgical intervention was open drainage of perinephric collection (6) and/or renorrhaphies (2). Four patients in this group developed urinary fistulae treated successfully with ureteral stents. Length of hospital stay was 9.6 days (3–25 days). In group 2, persistent hemodynamic instability led to nephrectomy in 1 case. The remaining 28 patients were managed conservatively, with endoscopic ureteric stenting in 5 cases. A persistent urinary extravasation with hyperthermia led to open drainage of perinephric urinoma (5) and renorrhaphy (2). No delayed nephrectomy was necessary. Average hospital stay was 12 days (5–21 days). Only 1 patient in this group developed hypertension. Conclusion: For most patients and with close follow–up available, conservative treatment represents a real alternative to open surgery in major blunt renal lacerations. In our experience, open surgery usually results in loss of renal parenchyma.

Therapeutical Strategies and Outcome of Polytraumatized Patients with Pelvic Injuries A Six-Year Experience

The combination of multiple injuries and pelvic ring disruption often represents a devastating injury pattern. This study evaluates therapeutical strategies and the outcome of 174 severely traumatized patients with pelvic ring injury (ISS: 32.1±11.1 patients) over a 6-year period. Patients were divided into 3 groups according to their hemodynamic status at admission. Forty-one patients in extremis (group A; ISS: 40.1±11.1 patients) which required the highest resuscitation efforts revealed a mortality rate of 90%. Many of these patients underwent crash laparotomy (44%)/thoracotomy (22%), aortic clamping (22%), and pelvic packing (44%). Patients with persistent hemodynamic instability (group B; n = 39; ISS: 34.2±9.6 patients) had a mortality rate of 26% (p<0.05 versus group A) with 14 patients (36%) undergoing emergency laparotomy. Mortality rate (5%) markedly (p<0.05) decreased in patients with stable hemodynamics despite a relatively high ISS (group C; n = 94; ISS: 27.6±9.4 patients). Hemorrhage could be controlled in all patients of group B and C, while 23 out of 41 patients (56%) in extremis died due to exsanguination during the first 24 hours after injury. Thus, treatment of patients in extremis must be focused on aggressive resuscitation and surgical intervention without extensive diagnostic procedures to effectively control lethal hemorrhage.

A sutureless technique for the relief of pulmonary vein stenosis with the use of in situ pericardium

Pulmonary vein (PV) stenosis develops as a progressive and usually lethal complication after surgical repair of total anomalous PV connection. Conventional surgical repair for the management of recurrent PV stenosis has been generally unsuccessful because of proliferative neointimal hyperplasia resulting in recurrent PV obstruction. The factors that result in recurrent stenosis after the usual types of patch venoplasty are unknown. We speculated that direct suturing of PVs and patch material may be the substrate for turbulent blood flow triggering intimal hyperplasia and eventual narrowing of the vein. On the basis of these considerations, we developed a sutureless technique for repairing PV stenosis with in situ pericardium. We present here its early but promising results. Patients PATIENT 1. Patient 1 was born in January 1995 with infradiaphragmatic total anomalous PV connection and severe obstruction of the descending vertical vein. On day 1, the infradiaphragmatic anomalous vein was ligated and the confluence was anastomosed to the left atrium under conditions of hypothermic circulatory arrest. At 6 months, the child had conspicuous tachypnea. Echocardiography revealed obstructed left PVs with a mean gradient of 7 mm Hg (peak 16 mm Hg) and suprasystemic right ventricular pressure. Angiocardiography demonstrated variable obstruction of all four PVs, with a mean pulmonary artery pressure of 38 mm Hg (systolic 92 mm Hg). At reoperation, obstruction of all PVs was confirmed. Under conditions of circulatory arrest, a pedicled flap of free right atrial wall–superior vena cava junction based at the inferior vena cava was used to patch the right-sided veins and carried behind the aorta to patch the left upper PV. The left lower vein was repaired with a flap created from the left atrial appendage. After that operation, the child had repeated admissions with respiratory tract infections, complicated at 1 year by hemoptysis. Echocardiography revealed recurrence of obstruction. At the second reoperation, atretic left-sided veins and severe stenosis of right-sided veins were noted. The PVs were opened, and an in situ pericardial sutureless patch was used for reconstruction. Echocardiography a year later showed patent veins, with mean gradients of 4 mm Hg on the right side and 5 mm Hg on the left. The estimated mean pulmonary artery pressure was 10 mm Hg. Perfusion lung scan showed 67% perfusion on the right side and 33% on the left. The child currently has no symptoms. PATIENT 2. Patient 2, a female infant, was born on January 1995 with total anomalous PV connection to coronary sinus with echocardiographic evidence of partial obstruction. At 2 weeks, she underwent repair consisting of unroofing of the coronary sinus, as described by Van Praagh and Harken. On completion of the procedure, the patient could not be weaned from cardiopulmonary bypass. At this time the right ventricular pressure was suprasystemic. The child was placed on extracorporeal membrane oxygenator and subsequently weaned after 3 days, with delayed sternal closure in 10 days as a result of persistent hemodynamic instability. Echocardiographic findings before discharge revealed unobstructed PV confluence–left atrium connection. However, echocardiography 4 months later revealed an obstructed right upper PV with a mean right ventricular pressure of 25 mm Hg. Perfusion scan showed 87% perfusion to the left lung and 13% to the right. Eleven months after the operation, echocardiography and cardiac catheterization revealed pulmonary hypertension, with a mean pulmonary artery pressure of 34 mm Hg and anatomically right PV stenosis. At reoperation, the presence of severe bilateral PV stenosis extending from left atrium a variable distance into the intraparenchymal PVs was confirmed. An in situ pericardial baffle was used for repair, as described here. Cardiac catheterization 6 months later revealed normal venous drainage on the left side and mild obstruction on the right side. The mean pulmonary artery pressure was 16 mm Hg. Perfusion lung scan showed 42% to left lung and 58% to right. The child has no symptoms at 15 months of postoperative follow-up. Technique. Standard cardiopulmonary bypass technique is used. The incision is made into the left atrium and extended into both upper and lower PV ostia separately (Fig. 1, A). This incision can be carried into the secondary, and if necessary, the tertiary branches of both the upper and lower lobe veins to a level at which the intima appears grossly normal. The pericardium overlying the entrance of the PVs is used to create an enlarged communication between the opened PVs and the left atrium. The neoatrium is created by suturing the pericardium to the epicardium of the left atrium, completely circumscribing the opening in the left atrium and PVs so that the PV effluent is contained by pericardium. The reconstruction is From the Division of Cardiovascular Surgery, Department of Surgery, Hospital of Sick Children, and University of Toronto Faculty of Medicine, Toronto, Ontario, Canada.

Current Treatment and Future Prospects for the Management of Acute Coronary Syndromes

Management of acute coronary syndromes, particularly unstable angina, acute myocardial infarction and non-Q-wave myocardial infarction, is one of the most common and costly problems facing modern medicine. Furthermore, the increasing availability of new research and clinical information relevant to the treatment of these conditions means that continuing reappraisal of management strategies is necessary. Accordingly, the Ushuaia conference, Tierra Del Fuego, Argentina, was convened to discuss current approaches and future treatment prospects for patients with these conditions. The conference was comprised of leading Argentinian cardiologists whose primary aim was to formulate consensus recommendations regarding the management of patients with acute coronary syndromes. The first of the major recommendations for the pharmacological management of acute coronary syndromes arising from the Ushuaia Consensus Conference was that aspirin (200 to 500mg initially, then 100 to 325 mg/day) should be administered to all patients except those for whom aspirin is absolutely (or relatively, depending on the clinician's discretion) contraindicated. In such cases, ticlopidine is a suitable alternative. Intravenous nitrates are indicated for patients with angina pain (24 to 48 hours' duration), ECG changes, recurrence of angina, or signs of heart failure; in other cases, oral, transdermal or sublingual nitrates may be administered. Use of beta-blockers is recommended except when absolutely contraindicated or when there is a strong suspicion of vasospasm as a dominant mechanism in angina. Intravenous administration of these agents is preferred in patients with tachycardia, arterial hypertension or angina. Calcium antagonists are generally not recommended as first choice therapy, but can be indicated (preferably using agents that decrease heart rate) when beta-blockers are contraindicated or when there is a strong suspicion of vasospasm as a dominant mechanism in angina. Calcium antagonists are also useful in combination with other drugs in patients with high blood pressure or treatment-refractory recurrent angina. Subcutaneous low molecular weight heparins and intravenous unfractionated heparin provide similar results and are indicated in a number of clinical situations. Emergency videocoronary angiography (VCA) is indicated in patients with persistent clinical and haemodynamic instability, recurrent ischaemia with heart failure, and refractory angina. Patients should also be referred for VCA if they have signs of left ventricular dysfunction, post-acute myocardial infarction angina with ECG changes, or ischaemia during functional studies. Post-VCA treatment will be determined by anatomical findings during VCA. Future prospects in the management of acute coronary syndromes include the development of more accurate prognostic markers and means of stratifying risk, such as sophisticated ECG criteria, serum markers of necrosis (e.g. troponin T and I), markers of thrombosis (e.g. D-dimer and fibrinopeptide A levels), markers of inflammation (e.g. reactive protein C, cell adhesion receptor expression, neopterine), and markers of 'good' prognosis (e.g. interleukin-10). Other pharmacological approaches under investigation include platelet IIb/IIIa receptor antagonists, clopidogrel and hirudin. Novel agents, such as anti-Xa, pentasaccharide, anti-tissue factor compounds, Ib receptor-blocking agents, agents that influence vascular endothelium and control cellular acidosis (e.g. HOE 642), macrolide antibiotics, HLA-DR system blockers and fusion compounds, are also in various stages of investigation or development.

Severe Liver Rupture and Tricuspid Valve Rupture in a Patient with Multiple Trauma

A patient with a severe liver injury and an acute cardiac failure due to a traumatic tricuspid valve failure is presented. During liver surgery, massive venous bleeding was caused by regurgitation of blood through the insufficient tricuspid valve. Right ventricular failure, leading to persistent hemodynamic instability, and caused by massive posttraumatic tricuspid regurgitation, has been treated with biological valve replacement. Diagnosis and management of posttraumatic tricuspid insufficiency are discussed.

Subacute ventricular free wall rupture complicating myocardial infarction

Myocardial free wall rupture accounts for between 8% and 17% of mortality after myocardial infarction. In up to 40% of cases death occurs subacutely over a matter of hours, not minutes. Illustrative clinical cases and data suggest that a high degree of clinical suspicion, along with the early use of echocardiography, could significantly reduce mortality resulting from myocardial free wall rupture complicating myocardial infarction. Myocardial free wall rupture should be suspected in patients with recent myocardial infarction who have recurrent or persistent chest pain, hemodynamic instability, syncope, pericardial tamponade, or transient electromechanical dissociation. In this clinical situation, emergent echocardiography showing a pericardial effusion or pericardial thrombus is highly suggestive of free wall rupture. Surgical exploration and rupture repair is the definitive diagnostic and therapeutic procedure.

PEDIATRIC TRAUMA

A recent proposal by some pediatricians is that they be primarily responsible for resuscitation and triage of injured children with surgical care being initiated only through consultation. To assess the need for operative intervention, a consecutive series of 376 children less than 15 years of age admitted to a regional trauma center was examined, in which 194 children had 254 operations. Mortality was 7.2%. Twenty-two children who presented with persistent hemodynamic instability (sys. BP less than 90 mm Hg) had a mortality of 73%. Children were divided into three severity groups based on the Revised Trauma Score (RTS). Of the severely injured children (RTS less than or equal to 6), 79% required emergent operative intervention; 42% and 14%, respectively, required emergent operation in the moderately (6 less than RTS less than 12) and minimally (RTS = 12) injured groups. The need for operative management is great, even in "minimally" injured children.