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J M Oropello

Publications and source records attributed to J M Oropello.

18 recordsLinked to original sources

Gastrointestinal complications in the intensive care unit.

Pathologic conditions affecting the abdomen are a significant cause of morbidity and mortality in the intensive care unit, but their importance is not widely recognized. This article presents several aspects of abdominal pathology that can occur in intensive care unit patients. This pathology may have a considerable impact on the prognosis and survival of the critically ill patient. The diagnostic contribution of laboratory tests and imaging is discussed. Conditions such as the abdominal compartment syndrome, acute mesenteric ischemia, gastrointestinal bleeding, diarrhea, abdominal sepsis, complications of entereal and parenteral nutrition, and ileus in critically ill patients are also reviewed.

Adolescent

Neurologic complications in the intensive care unit.

Neurologic complications resulting from critical illness and intensive care unit therapies are common, but frequently unrecognized because these patients are often intubated, sedated, and, occasionally, receiving neuromuscular blocking agents. Neurologic complications are associated with an increased intensive care unit mortality. This article discusses central nervous system complications that are secondary to critical illness or to therapeutic interventions in the critically ill patient.

Central Nervous System Diseases

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

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

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

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

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

Point-of-care testing in the intensive care unit. The intensive care physician's perspective.

Technological advancements have, for the first time, made the entire laboratory testing process feasible at the bedside. Physicians working in the intensive care unit have always had immediate access to patients' medical history, physical examination, and physiologic monitoring data, but had to wait for laboratory results. Using point-of-care testing, laboratory parameters targeted to critical illnesses can now be integrated into initial diagnostic assessments, on patient rounds, and during therapeutic maneuvers. The concept of point-of-care testing in the intensive care unit is relatively new, but as technology progresses, physicians will undoubtedly become aware and use it in the intensive care unit. This article focuses on the intensive care physician's perspective on laboratory testing, the evolution of the intensive care unit laboratory, advantages of point-of-care testing in that setting, new developments in arterial blood gas analyzers and monitors, and cost-effectiveness and incorporation of point-of-care testing.

Attitude of Health Personnel

Postoperative changes on brain SPECT imaging after aneurysmal subarachnoid hemorrhage. A potential pitfall in the evaluation of vasospasm.

Serial brain SPECT imaging was performed on patients after subarachnoid hemorrhage and surgical clipping of intracranial aneurysms. A total of 20 HMPAO scans were performed on 9 patients in whom clinical vasospasm did not develop. Areas of diminished regional cerebral blood flow (rCBF) were found near the operative site in 17 of 20 studies, which did not correlate with the patients' neurologic condition and were suggestive of postoperative edema. Brain SPECT imaging has a potentially valuable role to play in the evaluation of postoperative patients susceptible to vasospasm; however, it is important to be aware of postoperative changes in rCBF that are not related to vasospasm.

Brain

Abnormal coagulation profile in brain tumor patients during surgery.

Neurosurgical patients are at high risk for the development of thrombosis and thromboembolism. We compared the perioperative clotting factor and coagulation parameters of 20 patients undergoing elective craniotomy for brain tumors to those of 20 patients undergoing elective abdominal surgery. We also measured the levels of plasma arginine vasopressin to determine if changes in this hormone might be associated with changes in clotting factors, activated partial thromboplastin times, or bleeding times. The results demonstrated a significant reduction in partial thromboplastin times and bleeding times in the neurosurgery group, which began at the initiation of surgery and lasted to the end of the study (12 h postoperatively). Elevations in factor assays and plasma arginine vasopressin occurred in both groups during surgery, but there were no differences between the neurosurgical and abdominal surgical patients, except with Factor IX levels, which were elevated only in the neurosurgical patients. Serum osmolality and hemoglobin levels were significantly higher in the neurosurgical cohort. These results suggest that there are hemostatic differences between neurosurgical patients with brain tumors and abdominal surgery patients that cannot be explained solely by elevations in plasma arginine vasopressin or the clotting factors measured; these differences may be the consequence of perioperative variables such as dehydration and hyperosmolality.

Adult

Effects of acid-base correction on hemodynamics, oxygen dynamics, and resuscitability in severe canine hemorrhagic shock.

OBJECTIVE: To compare the effects of hypertonic saline, sodium bicarbonate, and Carbicarb resuscitation on acid-base balance, hemodynamics, and oxygen dynamics in a reperfused, canine hemorrhagic shock model. DESIGN: Prospective, randomized trial. SETTING: Laboratory at a university medical center. SUBJECTS: Thirty-five anesthetized, mongrel dogs. INTERVENTIONS: After the administration of anesthesia, the dogs were intubated and mechanically ventilated. Vascular catheters were inserted into each femoral artery, for continuous blood pressure monitoring, intermittent blood sampling, and for establishing controlled hemorrhage. A pulmonary artery catheter was inserted via the right jugular vein. Inhaled and exhaled gases were continuously analyzed using a metabolic gas monitor. The animals were subjected to 90 mins of controlled hemorrhagic shock. They were then randomly given a 2.5-mL/kg equimolar injection of 8.4% sodium bicarbonate, Carbicarb, or 5.84% hypertonic saline. The sodium load per kilogram of body weight was identical in all three groups. Thirty minutes later, the animals were retransfused with the shed blood over 15 mins and further observed for 120 mins. MEASUREMENTS AND MAIN RESULTS: Carbicarb and sodium bicarbonate both significantly increased bicarbonate concentrations compared with saline. Arterial and venous blood pH increased more with Carbicarb than with bicarbonate but this increase was not statistically significant. After shock but before retransfusion, all three treatments moderately increased blood pressure, cardiac index, oxygen delivery index, and oxygen consumption index to a similar extent. After retransfusion, blood pressure, cardiac index, and oxygen dynamics temporarily improved in all groups, without significant improvement in the bicarbonate and Carbicarb-treated animals, despite their excellent acid-base status. CONCLUSIONS: In severe canine hemorrhagic shock, Carbicarb, bicarbonate, and hypertonic saline appear to possess similar hemodynamic properties despite the buffering properties of bicarbonate and Carbicarb. The similar responses may be due to their identical sodium content. Arterial pH correction does not appear to further improve the responses to blood retransfusion.

Acid-Base Imbalance

Acute mesenteric ischemia: pathophysiology, diagnosis, and treatment.

Ischemia has traditionally been viewed as arising only from abnormalities of oxygen dynamics, namely the cellular hypoxia resulting from the imbalances between oxygen supply, consumption, and demand. Recently, it has become clear that such a view is too restrictive. Hypoperfusion may be caused by both anatomic and functional impediments to either inflow or to outflow from an organ. Furthermore, the pathophysiologic consequences are likely to involve not only cellular hypoxia, but also a restricted supply of nutrients and other important molecules and an abnormal elimination of physiologic wastes such as carbon dioxide. Hence the recommendation that ischemia be defined as a dual defect of oxygen deficit and carbon dioxide excess. AMI is, therefore, a severe anatomic or functional impediment to the splanchnic circulation, resulting in a dual defect of intestinal hypoxia and cellular hypercarbia. Although the functional and structural consequences of cellular hypoxia are well known, the pathophysiology of cellular hypercarbia has only begun to be explored. AMI syndromes include three related processes: occlusive mesenteric ischemia, nonocclusive ischemia, and sepsis-induced SI. Leakage of bacteria or bacterial toxins into the circulation during mesenteric ischemia forms the basis of the systemic components of this syndrome. Striving for an earlier diagnosis, treating the systemic (septic) consequences, and taking measures to promptly restore mucosal oxygen balance through aggressive pharmacologic and appropriate surgical intervention have significantly improved the prognosis. About 80% of patients with acute arterial embolism, 60% of those with nonocclusive ischemia, and only 20% of patients with arterial thrombosis are expected to live without significant residual nutritional deficits. The cause of death is usually sepsis and multisystem organ failure, and therefore, further reductions in mortality are likely to occur with the improved prevention and treatment of sepsis.

Acute Disease

Effects of pentoxifylline on hemodynamics, oxygen transport, and tissue metabolism in experimental, severe hemorrhagic shock.

BACKGROUND AND METHODS: It is hypothesized that pentoxifylline may be beneficial during shock states by improving tissue oxygenation. To test this hypothesis, we examined the effect of pentoxifylline on hemodynamics, oxygen delivery (DO2), and tissue metabolism during severe hemorrhagic shock. We conducted a placebo-controlled, randomized trial using anesthetized, mechanically ventilated dogs in hemorrhagic shock maintained at a mean arterial pressure of 45 to 50 mm Hg. Six animals were treated with a 10-mg/kg bolus of iv pentoxifylline followed by a continuous infusion at 5 mg/kg.hr. The controls consisted of six animals treated with saline. RESULTS: There were no significant differences between the groups before treatment. During 150 mins of posttreatment, repeated measurements of the control and pentoxifylline groups showed no significant differences in heart rate (HR), cardiac output, systemic and pulmonary vascular resistances, DO2, or blood lactate concentration (repeated-measures analysis of variance). CONCLUSIONS: In this acute, nonresuscitated, canine hemorrhagic shock model, pentoxifylline did not act as a vasodilator, or have any significant effect on HR, cardiac output, oxygen transport, or lactic acidosis.

Animals