Biomedical subjects

J A Lowell

Publications and source records attributed to J A Lowell.

7 recordsLinked to original sources

PubMed1992

Primary adenocarcinoma of third and fourth portions of duodenum. Favorable prognosis after resection.

Duodenal adenocarcinoma, a rare malignant lesion, is associated with a poor 5-year survival. Few series have addressed differences between resectable tumors of the proximal and distal duodenum. We reviewed records of 17 consecutive patients with adenocarcinoma of the duodenum who underwent resection: 10 had adenocarcinoma of the proximal duodenum, and seven had tumors of the distal duodenum. Most patients underwent pancreatoduodenectomy. Five patients with adenocarcinoma of the distal duodenum underwent segmental resection. No perioperative deaths occurred. Six of 10 patients with proximal tumors died of metastatic disease. Of the seven patients with tumors of the distal duodenum, five are alive without evidence of disease, and two died of unrelated causes. The survival of patients with adenocarcinoma of the distal duodenum is surprisingly good, and segmental resection is the procedure of choice.

Academic Medical Centers↗

PubMed1991

Venous access. Preoperative, operative, and postoperative dilemmas.

The past two decades have seen a tremendous increase in the use of central venous catheters and its associated complications. The increased sophistication that physicians now have with regard to nutritional and metabolic needs has escalated the use of central venous catheters. As the acquired immunodeficiency syndrome epidemic grows, so too will the number of patients with infections and metabolic complications, many of whom will have conditions severe enough to benefit from the use of central venous catheters to deliver antimicrobial drugs and other supportive intravenous therapy. Our ability to sustain patients with short-bowel syndrome also relies critically on central venous access. Likewise, treatment of patients with leukemias and certain solid tumors frequently requires placement of these catheters. Central venous catheters are essential for bone marrow transplantation. Efforts to minimize the risks associated with placement of a central venous catheter by more frequent use of catheter exchange rather than another venipuncture should be encouraged when possible. Techniques to prevent arrhythmia during overinsertion of guide wires are also important. Vigilant searches for, and prompt treatment of, catheter-related sepsis and central vein thrombosis are critical. Better prophylaxis against the development of catheter-related sepsis and catheter-related thrombosis is also needed. Further prospective investigations should be performed, however, to define precisely cost-effective methods of detection and duration of therapy for patients with both catheter-related sepsis and catheter-related thrombosis. Further advances in the technology and management of catheters need to continue to meet these ongoing challenges.

Arrhythmias, Cardiac↗

PubMed1990

Postoperative fluid overload: not a benign problem.

The incidence and consequences of fluid overload in the surgical ICU (SICU) have not been well defined, but may influence length of stay, days requiring mechanical ventilation, and mortality. Forty-eight consecutive patients admitted to our SICU were prospectively monitored for acute changes in weight and its impact on clinical management and outcome. When defined as a gain greater than 10% from their preoperative or premorbid weight (or an approximately 20% increase in total body water), 40% of patients had fluid overload. Patients were divided into three groups: those who had gained less than or equal to 10%, those with a weight gain between 11% and 20%, and those with greater than 20% increase in weight. Significant differences were found with respect to vasopressor dependence, colloid administration, and mortality. When indexed by initial Acute Physiology and Chronic Health Evaluation (APACHE II) mortality prediction scores, all groups had similar degrees of illness. On average, presumably due to volume limitations, patients were inadequately nourished during 85% of their SICU stay. Our results suggest that the morbidity of fluid overload can be significant, and warrants a fresh look at the methods of intraoperative fluid resuscitation.

Adult↗

PubMed1990

Dietary immunomodulation: beneficial effects on oncogenesis and tumor growth.

Our understanding of the interrelationship between nutrition, immunology, oncogenesis, and tumor growth is steadily increasing. Well known are the detrimental effects of malnutrition on host defenses. New work has shown that the addition of omega-3 polyunsaturated fatty acids or the amino acid arginine to the diet may significantly enhance immune function. These dietary manipulations have been shown to inhibit tumorigenesis and cancer spread in animal models, and form the basis for exciting new work in the prevention and treatment of cancer in humans.

Animals↗

PubMed1989

Neuromuscular and vascular hamartoma of the small bowel.

Neurovascular and muscular hamartoma is an unusual benign neoplasma of the small intestine. The clinical and pathological features of this lesion, which we recently encountered in a 91-year-old male, are the subject of this report and are discussed in the context of previously described cases.

Aged↗

PubMedDate not supplied

Incidence of arrhythmia with central venous catheter insertion and exchange.

The risk of complication during the insertion or exchange of central venous catheters has been well documented. The majority of complications involve mechanical problems associated with insertion. Although cardiac arrhythmia has been acknowledged as a possible complication, its incidence has never been quantified. We performed cardiac monitoring on patients during 51 central venous catheter insertions or exchanges to determine the incidence of cardiac arrhythmias during guidewire insertion. Forty-one percent of procedures resulted in atrial arrhythmias and 25% produced some degree of ventricular ectopy, 30% of these were ventricular couplets or greater. Ventricular ectopy was significantly more common in shorter patients (160 +/- 8 vs 168 +/- 11 cm, p less than 0.05) and when the catheter was inserted from the right subclavian position (43% ventricular ectopy vs 10% at the other sites). Other variables such as age, cardiac history, serum potassium, type of procedure, and catheter brand were not significant. It is our conclusion that over-insertion of the wire causes this cardiac stimulation. Despite the absence of morbidity or mortality in this study, this incidence of ventricular ectopy indicates that there is a distinct possibility of a malignant arrhythmia being precipitated by a guidewire. Some modification of the current protocol for these procedures seems indicated.

Arrhythmias, Cardiac↗

PubMedDate not supplied

Continuous v intermittent cimetidine infusion in critically ill hospitalized patients: role of TPN admixture as drug vehicle.

Previous studies suggest that continuous or intermittent cimetidine infusion provides a stable and sustained therapeutic blood concentration that maintains a gastric pH greater than 4.0. Twenty-seven patients receiving cimetidine were randomized to one of five treatments. Groups 1 and 2 were given cimetidine intermittently, whereas Groups 3, 4, and 5 received the drug continuously via a total parenteral nutrient (TPN) admixture. Group 1 was given 300 mg every 8 hours, and Group 2 received 300 mg every six hours. Groups 3, 4, and 5 received 600, 900, and 1200 mg per day, respectively, as a continuous infusion in the TPN admixture. Forty-eight individually prescribed TPN admixtures were used to deliver cimetidine continuously; 23 were composed of amino acids and glucose as base nutrients, whereas 25 contained amino acids, glucose, and lipids (3-in-1 or total nutrient admixtures). Serum levels of cimetidine were measured six times in 40 h (Group 1) or 42 h (Group 2-5). A two-way analysis of variance (ANOVA) revealed statistically significant differences in the serum cimetidine concentrations between groups (p less than 0.0001), but not with respect to time interval (p = 0.8687). No significant differences were noted in mean serum cimetidine concentrations between Groups 2 and 3, despite employing half the total dose in Group 3. Equivalent daily dosages were then stratified as the percentage of subtherapeutic (less than 500 ng/ml), therapeutic (500-1250 ng/ml), and supratherapeutic (greater than 1250 ng/ml) values.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗