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E Benjamin

Publications and source records attributed to E Benjamin.

At least 19 recordsLinked to original sources
PubMed1998

Goal-directed transesophageal echocardiography performed by intensivists to assess left ventricular function: comparison with pulmonary artery catheterization.

OBJECTIVES: Transesophageal echocardiography (TEE) is a valuable procedure for assessing left ventricular (LV) function, but it has not been widely applied in critical care because of the limited number of intensivists who are trained in echocardiography. This prospective study was designed to evaluate the feasibility of training intensivists to perform a goal-directed, limited-scope TEE to assess LV function in critically ill patients using a pediatric monoplane TEE probe. A secondary goal was to compare the usefulness of the TEE data with that of data obtained by a simultaneous pulmonary artery catheter (PAC). DESIGN: Prospective, blinded. SETTING: University teaching hospital. PARTICIPANTS: One hundred consecutive, intubated, intensive care unit patients. INTERVENTIONS: Five surgical intensivists with no previous background in echocardiography were trained under the supervision of two cardiologists to perform limited-scope TEE using a monoplane pediatric probe. One intensivist (A) reviewed the PAC data and recorded a diagnostic impression and therapeutic plan. A second intensivist (B), blinded to the PAC data, then performed TEE to determine cardiac volume, LV wall thickness, and LV global and regional wall motion. Intensivists A and B reviewed the data from both PAC and TEE, and intensivist A then formulated a new diagnosis and therapeutic plan. MEASUREMENTS AND MAIN RESULTS: Intensivists performed 48 TEE examinations under direct supervision of a cardiologist, and 52 without supervision, but reviewed poststudy. The average duration of TEE was 12 +/- 7 minutes. The intensivists' interpretations of TEE data were deemed correct in 93% of cases for LV wall thickness, 87% for intracardiac volume status, 81% for regional LV wall motion abnormalities, and 77% for global LV function. When the TEE and PAC technologies were compared, it was found that the TEE data disagreed with the PAC evaluation of intracardiac volume in 55% of cases and with the PAC assessment of myocardial function in 39% of cases. The post-PAC therapeutic recommendations were different from the post-TEE therapeutic recommendations in 58% of patients. CONCLUSIONS: Training intensivists in limited-scope, goal-directed TEE, using a pediatric monoplane probe to evaluate LV function, can be done rapidly and safely, and yield data pertinent to management of critically ill patients even in the early stages of skill acquisition.

Adult↗
PubMed1997

Tourette's syndrome and psychopathology in a child psychiatry setting.

UNLABELLED: Prior investigations of psychopathology among children with Tourette's syndrome (TS) have rarely used child psychiatry samples and sophisticated personality instruments. OBJECTIVE: To produce an objectively derived composite TS personality profile and to determine the rate of particular problems in a TS psychiatry sample compared with children with out TS from the same clinical practice. METHOD: Children (n = 33) referred to child psychiatrists because of emotional and behavior problems who were subsequently also found to meet DSM-III-R criteria for TS were assessed by the Personality Inventory for Children. RESULTS: Children with TS expressed high rates of psychopathology overall (composite 2.7 SD elevated) with depression, anxiety, and peculiar behavior having the highest values; depression occurred most frequently (73%), and attention-deficit hyperactivity disorder (55%) was no more common than among comparison group children and conduct problems (18%) were rarer. "Depression, anxiety, tension, and excessive worry" were characteristic of the actuarially derived modal TS personality. CONCLUSIONS: The prevalence and manifestations of psychopathology of children with TS in a child psychiatry practice are not identical with those reported in the literature. Child psychiatrists should be particularly vigilant of depressive symptoms and expect to encounter relatively few conduct problems compared with children without TS. Establishing "local prevalence rates" for children with TS seeking psychiatric evaluation can help guide the diagnostician and make diagnosis more assured.

Adolescent↗
PubMed1997

Thermodilution cardiac output measurement during simultaneous volume infusion through the venous infusion port of the pulmonary artery catheter.

OBJECTIVE: To determine the effect on thermodilution cardiac output (TDCO) measurements of continuous volume infusion through the right atrial venous infusion port of the pulmonary artery catheter. DESIGN: Prospective, blinded, randomly allocated crossover. SETTING: Surgical intensive care unit in a university hospital. PARTICIPANTS: Forty-nine hemodynamically stable patients between the ages of 43 and 84 in the intensive care unit and with a pulmonary artery catheter in place. INTERVENTIONS: Each patient received two room-temperature infusions (250 or 500 mL/hr) of 5% dextrose. Consecutive TDCO measurements were taken during each infusion and during a control period (no infusion). The sequence of infusion rates and control period was randomly determined. At both infusion rates, most patients exhibited a decrease in TDCO measurement of between 0.1 and 3.0 L/min. Although some patients exhibited an increase in measured TDCO, this increase was primarily between 0.1 and 0.5 L/min. MEASUREMENTS AND MAIN RESULTS: The mean TDCO measurements at infusion rates of 0, 250, and 500 mL/hr were 6.77, 6.49, and 6.47 L/min, respectively. Measured TDCO decreased on volume infusion by 0.3 +/- 0.13 L/min (mean +/- SD, p < 0.02). CONCLUSION: Rapid continuous infusion of fluid through the venous infusion port of the pulmonary artery catheter significantly limits the accuracy of simultaneous TDCO measurements. Optimally, TDCO measurements should be avoided during rapid volume infusion.

Adult↗
PubMed1997

Chlorine-induced anosmia. A case presentation.

Chlorine gas is known to be a potent irritant to the eyes, nose, throat and lungs with severe exposure resulting in pulmonary oedema and even death. There have been no case reports, however, of chlorine inducing anosmia. We present such a case, along with a review of the literature on the toxicology of chlorine and its effect on the nose.

Accidents, Occupational↗
PubMed1997

Effects of the stable prostacyclin analogue iloprost on mesenteric blood flow in porcine endotoxic shock.

OBJECTIVE: To determine the effects of the stable prostacyclin analog, iloprost, in a porcine model of endotoxin-induced mesenteric ischemia. DESIGN: Prospective, experimental, randomized, controlled study. SETTING: Animal research laboratory at a university medical center. INTERVENTIONS: Pigs were randomized to receive a constant infusion of iloprost (0.18 microg/kg/min) or an equivalent amount of carrier solution (normal saline) 30 mins before being infused with endotoxin (100 microg/kg over 1 hr). The infusion with iloprost or carrier solution was continued for the duration of the experiment. MEASUREMENTS AND MAIN RESULTS: Twelve pigs (six per group), weighing between 20 and 22 kg, underwent laparotomy during which a magnetic flowprobe was placed around the superior mesenteric artery and an ileal tonometer was inserted. Thirty minutes before they were infused with endotoxin, the animals were randomized to receive intravenous iloprost or normal saline. Endotoxin was infused centrally over a 60-min period. Animals received normal saline at a rate of 1.2 mL/kg/min which was begun at the start of the endotoxin infusion. Data were measured at the end of the endotoxin infusion (E60) and 1 hr later (E120). Mean arterial pressure was not affected by the dosage of iloprost used in this experiment. After resuscitation, the cardiac output returned to baseline in the iloprost-treated group but remained decreased in the control group (2.6 +/- 0.5 vs. 1.6 +/- 0.4 L/min). Superior mesenteric blood flow increased 34% above baseline levels in animals pretreated with iloprost (from 363 +/- 85 to 485 +/- 81 mL/min). The superior mesenteric PCO2 was significantly higher (53 +/- 9 vs. 40 +/- 5 torr; 7.1 +/- 1.2 vs. 5.3 +/- 0.7 kPa) and the ileal intramucosal pH was significantly lower (7.07 +/- .28 vs. 7.44 +/- .23) in the control group than in the iloprost-treated group. CONCLUSIONS: Pretreatment with intravenous iloprost effectively increased intestinal blood flow in this model of endotoxin-induced mesenteric ischemia. This action of the drug resulted in an attenuation of ileal intracellular acidosis. Since low-dose iloprost had no effect on mean arterial pressure, it may be a useful adjunct in the treatment of sepsis and septic shock.

Acidosis↗
PubMed1996

Treatment of septic shock with the tumor necrosis factor receptor:Fc fusion protein. The Soluble TNF Receptor Sepsis Study Group.

BACKGROUND: A recombinant, soluble fusion protein that is a dimer of an extracellular portion of the human tumor necrosis factor (TNF) receptor and the Fc portion of IgG1 (TNFR:Fc) binds and neutralizes TNF-alpha and prevents death in animal models of bacteremia and endotoxemia. METHODS: To evaluate the safety and efficacy of TNFR:Fc in the treatment of septic shock, we conducted a randomized, double-blind, placebo-controlled, multicenter trial. A total of 141 patients were randomly assigned to receive either placebo or a single intravenous infusion of one of three doses of TNFR:Fc (0.15, 0.45, or 1.5 mg per kilogram of body weight). The primary end point was mortality from all causes at 28 days. RESULTS: There were 10 deaths among the 33 patients in the placebo group (30 percent mortality), 9 deaths among the 30 patients receiving the low dose of TNFR:Fc (30 percent mortality), 14 deaths among the 29 receiving the middle dose (48 percent mortality), and 26 deaths among the 49 receiving the high dose (53 percent mortality) (P = 0.02 for the dose-response relation). Baseline differences in the severity of illness did not account for the increased mortality in the groups receiving the higher doses of TNFR:Fc. CONCLUSIONS: In patients with septic shock, treatment with the TNFR:Fc fusion protein does not reduce mortality, and higher doses appear to be associated with increased mortality.

APACHE↗
PubMed1996

Transthoracic bioimpedance can measure extravascular lung water in acute lung injury.

We used a porcine endotoxemic model of acute lung injury to compare extravascular lung water (EVLW) measured by right transthoracic bioimpedance to postmortem gravimetric EVLW measurements. Adult pigs were randomized into control (N = 5) or endotoxin groups [150 microgram/kg Escherichia coli lipopolysaccharide B for 1 hr followed by 3 hr of resuscitation for a thermodilution cardiac output less than 90% of baseline using either isotonic saline (N = 5) or isooncotic albumin (N = 5)]. Right lung resistance was measured using a novel electrode array and a highly sensitive analyzer and was used to calculate right lung resistivity. At the end of the experiment, animals in the endotoxin-albumin group had higher gravimetric EVLWs than those in the endotoxin-saline or control groups (P < 0.05). Right lung resistivity corrected for body weight significantly correlated with gravimetric EVLW (r2 = 0.49; SEE = 0.96; P = 0.0038). Using multiple regression analysis, a predictive equation for EVLW based on right lung resistivity, body weight, and mean pulmonary artery pressure was generated (r2 = 0.81; SEE = 0.60; P < 0.0001). These results demonstrate that right lung resistivity measurements can provide a noninvasive estimate of EVLW. In addition, crystalloid may be preferable to colloid for fluid resuscitation in noncardiogenic pulmonary edema.

Animals↗
PubMed1996

Does gastric tonometry work? No.

Gastrointestinal tonometry is supposed to diagnose gut mucosal hypoxia using gastric luminal PCO2 and arterial bicarbonatemia, which are substituted in a modified Henderson-Hasselbach equation. This article reviews some of the problems inherent to the multiple assumptions underlying this technique. Tonometry is influenced by several local factors and by systemic acid-base imbalances that are unrelated to oxygenation. Tonometry is a rather crude and cumbersome method of gut capnometry, a technology that may provide valuable information regarding visceral perfusion, but not necessarily oxygenation.

Bias↗
PubMed1996

Hypertensive, hypervolemic, hemodilutional therapy for aneurysmal subarachnoid hemorrhage. Is it efficacious? No.

Many neurosurgeons routinely use hypertensive, hypervolemic, hemodilutional, or hyperdynamic therapy (HT) in some form to prevent or to treat vasospasm. Despite the widespread use of this therapy during the past 20 years, however, there are no randomized, prospective, controlled clinical studies demonstrating that HT improves the short- or long-term neurologic outcome or survival after subarachnoid hemorrhage. Guidelines need to be developed to standardize the clinical application of HT, and well-controlled, prospective, randomized clinical trials must be conducted before HT can become an accepted treatment for vasospasm.

Blood Pressure↗
PubMed1996

Continuous fiberoptic arterial and venous blood gas monitoring in hemorrhagic shock.

STUDY OBJECTIVE: To compare the performance of continuous fiberoptic blood gas monitoring with standard, intermittent blood gas sampling in the measurement of arterial and central venous blood gases during marked hemodynamic changes. DESIGN: Prospective, consecutive, enrollment, experimental study. SETTING: Research laboratory at a university medical center. PARTICIPANTS: Seven anesthetized, mechanically ventilated pigs. INTERVENTIONS: Severe shock was induced by hemorrhage in pigs monitored by a pulmonary artery catheter, an arterial line, and two fiberoptic blood gas sensors: one intra-arterial, and the other inserted into the superior vena cava via right internal jugular vein cutdown. Fiberoptic blood gas monitor measurements were compared with standard intermittent blood gas sampling. MEASUREMENTS AND RESULTS: A total of 184 blood gas samples were compared in seven animals at baseline, during shock, and after resuscitation. The baseline mean (+/- 1 SD) cardiac output decreased from 4.0 +/- 0.9 to 1.2 +/- 0.6 L/min during shock and returned to baseline after retransfusion (3.9 +/- 1.3 L/min). The comparison of continuous fiberoptic blood gas monitoring with intermittent blood gas sampling showed a bias+/-precision of 0.035 +/- 0.047 for arterial pH, 0.021 +/- 0.031 for central venous pH, -4.09 +/- 2.96 mm Hg (-0.55 +/- 0.39 kPa) for arterial Pco2, -3.67 +/- 2.44 mm Hg (-0.49 +/- 0.3 3 kPa) for central venous Pco2, -5.79 +/- 9.64 mm Hg (-0.77 +/- 1.29 kPa) for arterial Po2, and -7.85 +/- 8.52 mm Hg (-1.05 +/- 1.14 kPa) for central venous Po2. CONCLUSIONS: Continuous fiberoptic blood gas monitoring agrees closely with standard intermittent blood gas sampling during severe hemodynamic shifts and has a comparable accuracy for both arterial and venous blood gas measurements. Changes in venous Pco2 have recently been shown to correlate with changes in global tissue perfusion (eg, changes in cardiac output). Such data, available immediately via continuous venous blood gas monitoring, may be useful for monitoring shock and the response to resuscitation.

Animals↗
PubMed1996

Postoperative intravenous infusion of alprostadil (PGE1) does not improve renal function in hepatic transplant recipients.

BACKGROUND: Acute renal failure is a frequent complication following orthotopic hepatic transplantation. A reduction in the synthesis of intrarenal vasodilator prostaglandins has been proposed as having an important role in the pathogenesis of renal insufficiency associated with hepatic dysfunction, as well as in the nephrotoxicity associated with cyclosporine and FK506 immunosuppressive therapy. Therefore, administration of vasodilator prostaglandins may improve renal function following hepatic transplantation. This study was designed to determine the effect of continuous intravenous alprostadil (prostaglandin E1) on postoperative renal function in hepatic transplant patients. STUDY DESIGN: In a randomized, double-blind, placebo-controlled trial, 21 patients who had undergone orthotopic hepatic transplantation and had a measured postoperative glomerular filtration rate (GFR) of less that 50 mL/minute received intravenous alprostadil at 0.6 microgram/kg/hour or placebo for five days. Glomerular filtration rate and effective renal plasma flow (ERPF) were measured by a single-injection clearance method using a radionuclide agent in 53 patients within 12 hours after admission to our surgical intensive care unit. Usual postoperative care was not modified. Radionuclide GFR and ERPF measurements were repeated on postoperative day 3. Serum creatinine was measured preoperatively and postoperatively on day 3 and on day 5. A 24-hour serum creatinine clearance was measured on days 1, 5, and 14. Urine output was recorded hourly during the infusion period. RESULTS: Ten patients received alprostadil, and 11 patients received placebo. There was a significant increase in GFR and ERPF in both groups on post-operative day 3 as compared with baseline values. There was no difference in GFR and ERPF between the two groups on day 3 (48 +/- 18 and 246 +/- 68 mL/minute in the alprostadil group compared with 53 +/- 17 and 270 +/- 131 mL/minute in the placebo group). Serum creatinine levels increased on day 3 in both groups but returned to baseline by day 5. CONCLUSIONS: These results indicate that a reversible decrease in GFR is common on hepatic transplant patients during the postoperative period. Administration of a continuous intravenous infusion of alprostadil in the immediate postoperative period had no effect on renal function when compared with placebo.

Adult↗
PubMed1995

Glutathione disulphide as a marker of reperfusion injury in ischaemic skin flaps.

Estimation of the oxidised form of glutathione (GSSG) in an ischaemic/reperfused organ is frequently employed as an indicator of oxidative stress created by the production of oxygen free radicals during the reperfusion period. The time course of oxidative stress and tissue damage in 19 ischaemic/reperfused guinea-pig island skin flaps was evaluated. No-flow ischaemia was induced in the flaps for 6 h in 7 animals, and for 8 h in 9 animals (a further 3 animals served as controls without ischaemia). Arterial and venous blood samples were obtained directly from the flap pedicle at baseline, 10, 30, and 60 min following reperfusion. Results suggest that a second focus of oxidative injury, possibly mediated by activated neutrophils, contributes to the overall process of reperfusion injury. Plasma levels of GSSG allow for a more sensitive quantification of oxidant stress within reperfused ischaemic flaps, and may serve as a useful tool in skin flap research.

Animals↗