Multicenter randomized comparison of xenon and isoflurane on left ventricular function in patients undergoing elective surgery.

BACKGROUND: Volatile anesthetics are commonly used for general anesthesia. However, these can induce profound cardiovascular alterations. Xenon is a noble gas with potent anesthetic and analgesic properties. However, it is uncertain whether xenon alters myocardial function. The aim of this study was therefore to investigate left ventricular function during anesthesia with xenon compared with isoflurane. METHODS: The authors performed a randomized multicenter trial to compare xenon with isoflurane with respect to cardiovascular stability and adverse effects in patients without cardiac diseases scheduled for elective surgery. Two hundred fifty-nine patients were enrolled in this trial, of which 252 completed the study according to the protocol. Patients were anesthetized with xenon or isoflurane, respectively. Before administration of the study drugs and at four time points, the effects of both anesthetics on left ventricular function were investigated using transesophageal echocardiography. RESULTS: Global hemodynamic parameters were significantly altered using isoflurane (P < 0.05 vs. baseline), whereas xenon only decreased heart rate (P < 0.05 vs. baseline). In contrast to xenon, left ventricular end-systolic wall stress decreased significantly in the isoflurane group (P < 0.05 vs. baseline). Velocity of circumferential fiber shortening was decreased significantly in the xenon group but showed a more pronounced reduction during isoflurane administration (P < 0.05 vs. baseline). The contractile index (difference between expected and actually measured velocity of circumferential fiber shortening) as an independent parameter for left ventricular function was significantly decreased after isoflurane (P < 0.0001) but unchanged using xenon. CONCLUSIONS: Xenon did not reduce contractility, whereas isoflurane decreased the contractile index, indicating that xenon enables favorable cardiovascular stability in patients without cardiac diseases.

Temporary right heart support with percutaneous jugular access.

PURPOSE: Temporary right heart bypass has shown to improve hemodynamic stability and safety in beating heart revascularization. We sought to evaluate feasibility and safety of a right ventricular assist device percutaneously implanted in the right jugular vein. DESCRIPTION: The A-Med jugular coaxial cannula (A-Med Systems Inc, West Sacramento, CA) is designed for percutaneous implantation. Blood from the right heart is drained through the outer tube of this two-cannula device to a microcentrifugal pump and returned into the pulmonary artery through the inner tube. EVALUATION: In 10 patients scheduled for elective coronary bypass grafting without cardiopulmonary bypass, a total of 27 coronary anastomoses were performed with right heart support. Arterial pressure was significantly higher with right heart support when the heart was dislocated to access posterior and posterolateral anastomosis sites. Implantation through the right internal jugular vein was feasible without complications in all patients and facilitated the procedure. CONCLUSIONS: This initial study suggests safety and feasibility of temporary right heart support using percutaneous jugular access for posterior and posterolateral coronary bypass grafting.

Surgical closure of combined symptomatic patent foramen ovale and atrial septum aneurysm for prevention of recurrent cerebral emboli.

BACKGROUND: Patients with patent foramen ovale (PFO) have an undefined but certainly considerable risk of repeated cerebral ischemia due to paradoxical embolism. Especially, if a cerebrovascular event has already occurred and the combination with an atrial septum aneurysm (ASA) is present this risk increases tremendously. The aim of this study was to demonstrate that surgical closure of PFO in combination with an ASA is safe and useful in preventing recurrent strokes. METHODS: Ten patients with previous cerebral ischemia, proven by CT or MRI, and PFO in combination with an ASA were prospectively scheduled for surgical closure. Patients with extracardiac sources of embolic disease were excluded from this study. However, one patient suffered from a hypercoagulability syndrome. RESULTS: All patients (mean age 35.5 +/- 19.1 years) underwent direct suture of the PFO and plication of the ASA with the aid of cardiopulmonary bypass and cardioplegic arrest (n = 3) or ventricular fibrillation (n = 7). Mean operation time was 123.1 +/- 20.2 minutes; mean bypass time was 34.5 +/- 9.9 minutes. There was no mortality or significant postoperative morbidity. Mean hospital stay was 5.1 +/- 1.5 days. During a follow-up of >4 years, no recurrent stroke or transient ischemic attack occurred and no patient received anticoagulation therapy. CONCLUSION: Our data suggest that surgical closure of PFO in combination with ASA in patients with previous stroke is safe and efficacious to prevent recurrent strokes and avoids lifelong anticoagulation.

The effect of high thoracic epidural anesthesia on systolic and diastolic left ventricular function in patients with coronary artery disease.

In patients with coronary artery disease, vasoconstriction is induced through activation of the sympathetic nervous system. Both alpha1- and alpha2-adrenergic epicardial and microvascular constriction are potent initiators of myocardial ischemia. Attenuation of ischemia has been observed when sympathetic nervous system activity is inhibited by high thoracic epidural anesthesia (HTEA). However, it is still a matter of controversy whether establishing HTEA may correspondingly translate into an improvement of left ventricular (LV) function. To clarify this issue, LV function was quantified serially before and after HTEA using a new combined systolic/diastolic variable of global LV function (myocardial performance index [MPI]) and additional variables that more specifically address systolic (e.g., fractional area change) or diastolic function (e.g., intraventricular flow propagation velocity [Vp]). High thoracic epidural catheters were inserted in 37 patients scheduled for coronary artery surgery, and HTEA was administered in the awake patients. Echocardiographic and hemodynamic measures were recorded before and after institution of HTEA. HTEA induced a significant improvement in diastolic LV function (e.g., Vp changed from 45.1 +/- 16.1 to 53.8 +/- 18.8 cm/s; P < 0.001), whereas indices of systolic function did not change. The change in the diastolic characteristics caused the MPI to improve from 0.51 +/- 0.13 to 0.35 +/- 0.13 (P < 0.001). We conclude that an improvement in cardiac function was due to improved diastolic characteristics.

Aminoterminal pro type B natriuretic peptide as a predictive and prognostic marker in patients with chronic heart failure.

BACKGROUND: B-type natriuretic peptide (BNP) is released from the cardiac ventricles in response to increased wall tension. We studied the relation of NT-proBNP to Heart Failure Survival Score (HFSS) and New York Heart Association (NYHA) class in patients with chronic heart failure (CHF). We also studied the impact for recipient selection for cardiac transplant and assessed it as a predictive and prognostic marker of CHF. METHODS: A total of 550 patients with dilative cardiomyopathy (n = 323), and coronary artery disease (n = 227) were prospectively examined. All patients underwent spiroergometry, echocardiography, right heart catheterization, and electrocardiogram. Routine blood levels and NT-proBNP were measured. The clinical selection for cardiac transplant candidates was adjudicated by 2 independent cardiologists who were blinded to the results of NT-proBNP assays. Clinical outcome and predictive power of NT-proBNP were analyzed. RESULTS: NT-proBNP levels in patients clinically considered for cardiac transplantation were significantly higher (2293 ng/ml vs 493 ng/ml; p < 0.001). The receiver operating characteristic (ROC) analysis regarding transplant candidacy showed an area under the ROC curve (AUC) of 0.84 +/- 0.01 for HFSS, 0.86 +/- 0.001 for NYHA, and 0.96 +/- 0.01 for NT-proBNP. Patients with increasing NT-proBNP levels or remaining elevated levels despite adequate heart insufficiency treatment were maintained with left ventricular assist device implantation (n = 10) or urgent heart transplantation (n = 2). Patients with NT-proBNP levels above 5000 pg/ml had a mortality rate of 28.4% per year. Twenty-eight patients died during the observation period; all these patients were within NYHA Classes 3 and 4 (NT-proBNP 5423 +/- 423 ng/ml). CONCLUSIONS: NT-proBNP discriminates patients at high likelihood of being a candidate for transplantation and provides prognostic informations in patients with CHF. NT-proBNP levels above 5000 pg/ml at admission were associated with death, and these levels markedly discriminated candidates for left ventricular assist devices or urgent transplantation.

Transient hemiplegia in posterior instrumentation of scoliosis.

STUDY DESIGN: A case of transient hemiplegia during posterior correction and instrumentation of scoliosis in an 18-year-old woman. OBJECTIVE: To present a case of transient hemiplegia most probably resulting from an arteriovenous fistula. SUMMARY OF BACKGROUND DATA: Neurologic impairment in spinal surgery is a feared complication. Common reasons are direct or indirect trauma to neural elements, intraoperative hypotension, ischemia, bleeding, metabolic dysbalances, or drug effects. Review of the literature did not reveal any case of transient hemiplegia similar to the presented one in which none of the mentioned pathologies could be found. CASE SUMMARY: An 18-year-old woman with a right long thoracic lordoscoliosis measuring 67 degrees Cobb angle and a marfanoid phenotype underwent posterior correction and transpedicular instrumentation from T3 to L2. After uneventful correction of the deformity through rod rotation, the wake-up test revealed a right-sided hemiplegia without facial asymmetry or other neurologic abnormalities affecting structures above the spinal cord. The rods were removed, the pedicle screws left in place, and the patient was turned on her back. Within 30 minutes after extubation, the neurologic deficits disappeared completely. Extensive diagnostic workup, including magnetic resonance angiography, did not show any pathologic findings explaining the transient hemiplegia. Two weeks later, the surgical correction was completed. After rod rotation again, right-sided hemiplegia was found in the wake-up test. Leaving the correction and after finalizing surgery, the patient was turned on her back and a 5 x 3-cm mass became apparent in her right sternocleidomastoid region. Color-coded duplex sonography revealed an arteriovenous fistula between the right external carotid artery and the right internal jugular vein. After extubation, the mass disappeared and within minutes all neurologic functions returned to normal again. CONCLUSIONS: Spine surgeons should be aware of arteriovenous malformations as a potential cause of neurologic disturbances.

Xenon improves recovery from myocardial stunning in chronically instrumented dogs.

In this study we tested the hypothesis that inhalational administration of xenon improves recovery from myocardial stunning. Ten dogs were chronically instrumented for measurement of heart rate; left atrial, aortic, and left ventricular pressure; coronary blood-flow velocity; and myocardial wall-thickening fraction. Regional myocardial blood flow was determined with fluorescent microspheres. Catecholamine plasma levels were measured by high-performance liquid chromatography. An occluder around the left anterior descending artery (LAD) allowed the induction of a reversible LAD ischemia. Animals underwent 2 experimental conditions in a randomized crossover fashion on separate days: (a) 10 min of LAD occlusion under fentanyl (25 microg. kg(-1). h(-1)) and midazolam (0.6 mg. kg(-1). h(-1)) (control) and (b) a second ischemic episode under the same basal anesthesia with concomitant inhalational administration of 75 +/- 1 vol% xenon (intervention). Anesthesia was induced 35 min before LAD occlusion and was discontinued after 20 min of reperfusion. Dogs receiving xenon showed a significantly better recovery of wall-thickening fraction up to 12 h after ischemia. The increase in plasma epinephrine during emergence from anesthesia and in the early reperfusion period was significantly attenuated in the xenon group. There were no differences between groups concerning global hemodynamics, blood-flow velocity, or regional myocardial blood flow. In conclusion, inhalational administration of 75 vol% xenon improves recovery from myocardial stunning in chronically instrumented dogs under fentanyl/midazolam anesthesia.

A-type and B-type natriuretic peptides in cardiac surgical procedures.

UNLABELLED: This study was performed to determine the secretion pattern and prognostic value of A-type (ANP) and B-type (BNP) natriuretic peptide in patients undergoing cardiac surgical procedures. We measured ANP and BNP in patients undergoing coronary artery bypass grafting (CABG) with (n = 28) or without (n = 32) ventricular dysfunction and in patients undergoing mitral (n = 21) or aortic (n = 24) valve replacement, respectively. Postoperative mortality was recorded up to 730 days after operation. ANP, but not BNP, concentrations were closely associated with volume reloading of the heart after aortic cross-clamp in all patients. The secretion pattern of BNP during surgery was much less uniform. BNP, but not ANP, concentrations correlated with aortic cross-clamp time (r(2) = 0.32; P = 0.006) and postoperative troponin I concentrations (r(2) = 0.22; P = 0.0009) in bypass patients, and preoperative BNP increases were associated with a more frequent postoperative (2-yr) mortality in these patients. Markedly increased preoperative BNP concentrations in mitral (3-fold) and aortic (14-fold) valve disease patients did not further increase during cardiopulmonary surgery. The data suggest that ANP is primarily influenced by intravascular volume reloading of the heart after cross-clamp, whereas the secretion of BNP is related to other factors, such as duration of ischemia and long-term left ventricular pressure and/or excessive intravascular volume. BNP, but not ANP, was shown to be a mortality risk predictor in patients undergoing CABG. IMPLICATIONS: A-type natriuretic peptide is primarily influenced by volume reloading of the heart after cross-clamp, whereas the secretion of B-type natriuretic peptide (BNP) is related to the duration of ischemia and long-term left ventricular pressure and/or volume overload. Preoperative BNP, but not postoperative BNP, concentrations predict long-term outcome after coronary artery bypass grafting.

Reversible cardiac sympathectomy by high thoracic epidural anesthesia improves regional left ventricular function in patients undergoing coronary artery bypass grafting: a randomized trial.

HYPOTHESIS: To evaluate the effects of high thoracic epidural anesthesia (TEA) on global and regional myocardial function and on perioperative coronary risk in patients undergoing coronary artery bypass grafting. DESIGN, SETTING, AND PATIENTS: Prospective and randomized clinical trial blinded for the primary outcome measure of 73 patients scheduled for coronary artery bypass grafting who had a left ventricular ejection fraction of 50% or more conducted from February 1, 2000, through August 31, 2000, at University Hospital, Münster, Germany. INTERVENTIONS: Of 73 randomized patients, 37 were control subjects (who received general anesthesia only) and 36 were in the group who received general anesthesia and high TEA. MAIN OUTCOME MEASURES: The primary outcome measure was regional left ventricular function after myocardial revascularization, assessed by transesophageal echocardiography. We further determined the plasma concentrations of cardiac troponin I and atrial and brain natriuretic peptides. Secondary outcome measures were postoperative complications recorded to 14 days and mortality recorded to 720 days. RESULTS: High TEA was effective in all patients of this group, the somatosensory block extended from T1 through T7 vertebrae. Regional left ventricular function was significantly improved (mean [SD] global wall motion index, 0.74 [0.18] vs 0.38 [0.16]; P<.05), and cardiac troponin I concentrations were reduced by 72% (mean [SD], 5.7 [1.5] vs 1.6 [0.7] ng/mL, P<.05) in patients with high TEA. Natriuretic peptide concentrations peaked during reperfusion (atrial natriuretic peptide) and 24 hours after reperfusion (brain natriuretic peptide). High TEA reduced the mean (SD) peak concentrations of atrial natriuretic peptide by 54% (211 [63] vs 98 [33] ng/mL, P =.03) and brain natriuretic peptide by 43% (189 [39] vs 108 [21] ng/mL, P =.01). One of 36 patients who received high TEA and 3 of 37 controls died. CONCLUSIONS: Reversible cardiac sympathectomy by high TEA improves regional left ventricular function and reduces postoperative ischemia after coronary artery bypass grafting. These effects of high TEA may improve the long-term outcome after myocardial revascularization.

Spontaneous splenic rupture after a left-side thoracotomy: report of a case.

We herein describe the case of a 59-year-old man who experienced a spontaneous splenic rupture 12 h after undergoing a left-side thoracotomy for a wedge resection of an unknown pulmonary nodular tumor following a history of malignant melanoma. He demonstrated no special abdominal diseases or traumas, except an uneventful cholecystectomy 12 years previously. Preoperatively, he was not on anticoagulation, aspirin, or nonsteroidal anti-inflammatory medication, and all coagulation tests were inconspicuous. At 12 h after lung surgery the patient showed signs of progredient hypovolemic shock. After ultrasonography, which showed a moderate amount of free intra-abdominal liquid, the patient was urgently taken to the operation room. Bleeding resulted from a rupture of an encapsulated hematoma from the spleen. No signs of adhesion around the spleen or of an injury of the left diaphragm were observed. A pathological analysis of the spleen revealed a normal dimension and a normal histological structure without any evidence of a hematological or neoplastic disease. The patient was discharged on the 12th day after surgery. A review on the literature and the differential diagnosis of this unusual case is presented and discussed.

Endogenous glycosides in critically ill patients.

OBJECTIVE: To determine the incidence of critically ill patients displaying endogenous digitalis-like-immunoreactive substances (DLIS) and to examine the relationship of these hormones to routine laboratory variables, the underlying disease, myocardial function, hemodynamic status, severity of illness, systemic inflammation, and mortality rate. DESIGN: Sera of 401 consecutive critically ill patients, not treated with cardiac glycosides, were analyzed for DLIS (digitoxin and digoxin, TDx; Abbott Diagnostics, North Chicago, IL) and endogenous ouabain. Normal values of endogenous ouabain were determined in 62 healthy volunteers. We measured pro- and anti-inflammatory mediators (L-selectin, tumor necrosis factor-alpha, interleukin-1beta, interleukin-2, interleukin-6, interleukin-10), C-reactive protein, and serum amyloid A protein as well as patients' Acute Physiology and Chronic Health Evaluation II and Goris scores. In a subgroup of patients with a pulmonary artery catheter (n = 95), we determined cardiac output, pulmonary artery occlusion pressure, systemic and pulmonary vascular resistance, left ventricular stroke volume, and right and left stroke work. SETTING: Two surgical intensive care units of an university hospital. SUBJECTS: Sera of 401 consecutive critically ill patients. INTERVENTIONS: Blood sampling. MEASUREMENTS AND MAIN RESULTS: Of the 401 patients tested, 343 had nonmeasurable DLIS concentrations (DLIS-negative), and 58 (14.5%) had positive digoxin (n = 18) or digitoxin (n = 34) concentrations (DLIS-positive) or were positive in both tests (n = 6). Mean endogenous ouabain concentrations were nine-fold increased in DLIS-positive (3.59 +/- 1.43 nmol/L) and three-fold increased in DLIS-negative (1.34 +/-.81 nmol/L) patients compared with controls (0.38 +/- 0.31 nmol/L). DLIS and ouabain concentrations closely correlated with the Acute Physiology and Chronic Health Evaluation II and Goris score and were associated with increased concentrations of transaminases, bilirubin, aldosterone, cortisol, serum creatinine, fractional sodium excretion, proinflammatory mediators, C-reactive protein, and serum amyloid A (p

The impact of the pro- and anti-inflammatory immune response on ventilation time after cardiac surgery.

BACKGROUND: Cardiac surgery using cardiopulmonary bypass (CPB) may induce a systemic inflammatory response syndrome (SIRS), which is associated with an increased risk of postoperative morbidity and mortality. The intention of this pilot study was to investigate the influence of the pro- and anti-inflammatory cytokine responses as well as of released adhesion molecules and endotoxin on the time requirements for assisted postoperative respiration following CPB surgery. METHODS: One hundred consecutive patients undergoing elective coronary artery bypass grafting (CABG) using CPB were prospectively investigated. Blood levels of cytokines, adhesion molecules, and endotoxins were serially measured at four time points perioperatively. RESULTS: All patients survived the observation period. Eighty-five patients were uneventful (group 1), whereas 15 patients required prolonged ventilation (34.8 +/- 9.2 h; group 2). All patients developed a pro-inflammatory and a compensatory anti-inflammatory cytokine response. An endotoxin liberation was found in parallel. The prediction of prolonged respirator dependence may be possible at completion of surgery using a combined data pattern analysis, including interleukin (IL)-6, IL-8, IL-4, endotoxins, vascular cell adhesion molecule (VCAM)-1, age, and cross clamp (x-clamp) time. Using arbitrary cutoff points improved sensitivity (0.92), specificity (0.90), positive prediction (0.87), and negative prediction (0.85) (all P < 0.02), and the ODD ratio (2.1) was found. CONCLUSIONS: Cardiac surgery and CPB induces both a pro- and anti-inflammatory immune response. The use of a data pattern instead of several individual parameters seems advantageous for individualized predictions on postoperative recovery in CPB surgery.

Short-term administration of ethanol does not affect functional recovery from myocardial stunning in awake dogs.

UNLABELLED: Chronic ingestion of small doses of ethanol protects the myocardium from ischemic damage. It was demonstrated that short-term administration of ethanol (SAE) enhances the recovery of stunned myocardium in acutely instrumented, anesthetized dogs. It is unclear whether this beneficial effect of SAE also occurs in awake dogs. Therefore, we investigated the effects of SAE on regional myocardial stunning in awake dogs. Thirty-six dogs were chronically instrumented for measurement of heart rate, left atrial, aortic, and left ventricular pressure, left systolic ventricular contactility (dP/dt(max)) and diastolic ventricular function (dP/dt(min)), and regional myocardial wall-thickening fraction (WTF). Occluders around the left anterior descending (LAD) artery allowed the induction of reversible ischemia in the LAD-perfused myocardium. The dogs were assigned to one of three groups that differed in the dose of ethanol administered in the ethanol experiment (I, 0.125 g/kg [n = 12]; II, 0.25 g/kg [n = 12]; III, 0.5 g/kg [n = 12]). In each group, the dogs underwent two ischemic episodes (randomized crossover fashion; separate days): 10 min of LAD occlusion after the application of ethanol IV over 30 min (ethanol group) and without ethanol (control). WTF and hemodynamic variables were measured at baseline and at predetermined time points until complete recovery of myocardial stunning occurred. LAD-ischemia led to a significant decrease of LAD-WTF in all groups. There was no difference in WTF and hemodynamic variables with or without SAE during reperfusion. We conclude that SAE (0.125 g/kg, 0.25 g/kg, and 0.5 g/kg) does not significantly affect myocardial stunning in conscious dogs. IMPLICATIONS: In contrast to previous experiments in anesthetized dogs, short-term administration of ethanol does not alter myocardial stunning in conscious dogs.

Tissue engineering of heart valves: formation of a three-dimensional tissue using porcine heart valve cells.

Tissue engineering is a promising approach to obtaining lifetime durability of heart valves. The goal of this study was to develop a heart valve-like tissue and to compare the ultrastructure with normal valves. Myofibroblasts and endothelial cells were seeded on a type I collagen scaffold. The histologic organization and extracellular matrix were compared in light and electron micrographs. Radiolabeled proteoglycans were characterized by enzymatic degradation experiments. In tissue engineered specimens, cross sectional evaluation revealed that the scaffold (300 microm) was consistently infiltrated with myofibroblasts. Both sides were covered with a multicellular layer of myofibroblasts and overlaid by endothelial cells (50 microm). A newly formed extracellular matrix containing collagen fibrils and proteoglycans was found in the interstitial space. Collagen fibrils with a 60 nm banding pattern were found in both specimens. Small sized proteoglycans (65 nm) were associated and aligned at intervals of 60 nm with collagen fibrils. Large sized proteoglycans (180 nm) were located outside the collagen bundles in amorphous compartments of the extracellular matrix. The majority of glycosaminoglycans were chondroitin/dermatan sulfate, and a minority were heparan sulfate. The morphology and topography of cells and the organization of extracellular matrix in artificial tissues strongly resembles those of native valve tissues.

Leukocyte activation and phagocytotic activity in cardiac surgery and infection.

BACKGROUND: Cardiac surgery (CS) using cardiopulmonary bypass (CPB) is associated with cellular and humoral defense reactions termed the systemic inflammatory response syndrome. Leukocyte activation is one of its causative mechanisms which may be aggravated by additional infection. METHODS AND RESULTS: Eighty-five patients undergoing CS with CPB were prospectively investigated. Leukocyte counts, elastase, and phagocytotic activity were measured from 24 h preoperatively up to 7 days postoperatively. Seventy-nine patients had an uneventful course (group 1) while six patients developed a systemic infection (group 2). Leukocytes and elastase levels increased postoperatively (p<0.01) and were significantly higher in group 2 (p<0.01). In both groups a decrease of leukocyte/elastase ratio occurred (p<0.002), no differences between groups were observed. The phagocytotic activity, representing the circulating cells of the reticuloendothelial system (RES), dropped on day 1 (p<0.05), and increased thereafter above baseline levels (p<0.001). No differences of RES function between groups was observed, the initial drop on day 1 in both groups was compensated by the quality of phagocytotic ability of each cells. CONCLUSION: Leukocyte activation after CS with CPB occurs. It is associated with a regular RES function and similarly leukocyte/elastase ratios in both groups, suggesting an adequate immune response. Therapeutic interventions resulting in depletion of leukocytes to alleviate reperfusion injury might impair the immune response of those patients acquiring perioperative infection and should be approached with caution. Leukocyte depletion maybe effective in patients for whom an extended period of CPB was required. Further investigations to prove this hypothesis awaits confirmation.

Crossing atrial thrombus in a patient with recurrent pulmonary embolism.

OBJECTIVES: To report the detection of a thrombus entrapped in a patent foramen ovale by echocardiography in a patient with recurrent pulmonary embolism. DESIGN: Case report. SETTING: Intensive care unit of a university hospital. PATIENT: A 62-yr-old man with initial deep venous thrombosis and recurrent minor pulmonary embolism followed by a severe embolic event with transitory hemiparesis 10 days after prostatectomy. INTERVENTION: Systemic anticoagulation, surgical removal of a crossing atrial thrombus, closure of a patent foramen ovale, and venous thrombectomy. MEASUREMENTS AND MAIN RESULTS: Transesophageal echocardiography revealed a large thrombus entrapped in a patent foramen ovale with portions in all four heart chambers. Intraoperatively, a 19-cm-long thrombus, shaped like the pelvic veins, was found. The patient was successfully weaned from cardiopulmonary bypass, requiring temporary positive inotropic support because of right ventricular dysfunction. Within 24 hrs of the operation, the patient was discharged to the intermediate care unit. CONCLUSIONS: Recurrent pulmonary embolism can potentially result in paradoxic embolism in patients with a patent foramen ovale. In such patients, it may be crucial to monitor right ventricular function and exclude right-to-left shunts by transesophageal echocardiography, regardless of clinical symptoms. The patent foramen ovale should be closed. This case emphasizes an important indication for transesophageal echocardiography in critically ill patients.

Hyponatremia in a pediatric stroke patient: syndrome of inappropriate antidiuretic hormone secretion or cerebral salt wasting?

OBJECTIVE: To determine the potential role of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in the pathogenesis of cerebral salt wasting. DESIGN: Clinical case report. SETTING: Regional pediatric intensive care unit. PATIENT: A 3-yr-old boy with a cerebral infarct secondary to traumatic carotid artery dissection who developed hyponatremia associated with weight loss and excessive renal sodium excretion on the sixth day after hospitalization. MEASUREMENTS AND MAIN RESULTS: Plasma concentrations of ANP, BNP, antidiuretic hormone, and renin were determined serially and compared with concentrations measured in a group of eight healthy children undergoing elective surgical procedures. Compared with controls, ANP and BNP plasma concentrations on the eighth day after hospitalization were increased 1.9-fold and 7.7-fold, respectively. Thereafter, the course of ANP and BNP paralleled that of sodium and H2O excretion and remained elevated until the 14th (BNP) and 16th (ANP) days after hospitalization. Serum antidiuretic hormone and renin concentrations were within normal ranges during the entire observation period. CONCLUSION: Cerebral salt wasting is associated with elevated plasma concentrations of ANP and BNP. Natriuretic peptides may play a role in the pathogenesis of this syndrome.

Effect of the interleukin-6 promoter polymorphism (-174 G/C) on the incidence and outcome of sepsis.

OBJECTIVE: A biallelic polymorphism within the human interleukin (IL)-6 gene promoter region (-174 G/C) has been shown to affect IL-6 transcription in vitro and IL-6 plasma levels in healthy adults. Because IL-6 is excessively released into the circulation during sepsis and closely correlates with the clinical course, we studied whether this promoter polymorphism has an effect on the incidence and/or outcome of sepsis. DESIGN: Population-based association study in critically ill patients and healthy controls. SETTING: Surgical intensive care unit (ICU) in a German university hospital. PATIENTS: Surgical patients (n = 326) of German Caucasian origin with an ICU stay of at least 3 days admitted between 1997 and 1999 were prospectively enrolled. In a subset of 50 patients, sepsis was diagnosed according to consensus criteria (American College of Chest Physicians 1992). Healthy sex-matched adults of the same ethnic and geographic background served as controls. INTERVENTIONS: Blood sampling. MEASUREMENTS AND MAIN RESULTS: The (-174 G/C) polymorphism was genotyped by an allele-specific polymerase chain reaction. IL-6 plasma levels were determined by enzyme-linked immunosorbent assay. Genotype distribution and allele frequencies did not differ significantly between patients with or without sepsis and healthy controls. In patients who finally succumbed to sepsis, significantly less GG homozygotes were observed compared with survivors (p = .008). Median systemic IL-6 levels in septic patients closely correlated with outcome (p < .0001) but were not associated with the IL-6 promoter genotype. CONCLUSIONS: The IL-6 promoter polymorphism (-174 G/C) does not affect the incidence of sepsis. However, the GG homozygous genotype is significantly associated with an improved survival in sepsis. Because this association is independent from the systemic IL-6 response, we suggest that other genetically linked polymorphisms may be the primary cause.