Biomedical subjects

L Sauer

Publications and source records attributed to L Sauer.

15 recordsLinked to original sources

PubMed1998

[Electro-cardiographic correlation in the diagnosis of left ventricular hypertrophy].

PURPOSE: To compare the efficacy of four electrocardiographic criteria: Sokolov, Gubner, Cornell and Romhilt indexes, in the diagnosis of left ventricular hypertrophy (LVH) in hypertensive patients. METHODS: LVH was analyzed in the electrocardiogram of 30 ambulatory patients presenting with systemic arterial hypertension, classified as mild, moderate and severe, according to the following indexes: Sokolov > or = 35 mm, Gubner > or = 22 mm, Romhilt > or = 5 points and Cornell > or = 20 mm for women and 28 mm for men. Sensitivity, specificity, diagnostic accuracy and other diagnostic variables were determined Mass index of the left ventricle, > or = 98 g/m2 for women and > or = 120 g/m2 for men, obtained by echocardiography, was considered the gold standard for the diagnosis of LVH. RESULTS: When electrocardiographic criteria were considered separately, the Sokolov index showed the highest accuracy, with a sensitivity of 40%, diagnostic accuracy of 50% and specificity of 100%; the second most accurate index was Gubner, and Romhilt and Cornell indexes followed. When at least one of the indexes was positive, the sensitivity was 52% and diagnostic accuracy was 57%. CONCLUSION: The four electrocardiographic indexes were not diagnostic of LVH, when analyzed either separately or together. Considering the high prevalence of this pathological condition, we conclude that a more accurate diagnostic method should be used in this diagnosis.

Adult↗

PubMed1990

Operative techniques in the fetal rabbit.

The development of fetal surgical techniques has made the antenatal correction of congenital defects possible. These techniques have evolved from trials with animal models, permitting increasingly sophisticated operations with low morbidity and mortality. Experimental models range from large animals offering longer gestations but with single pregnancies and high cost, to smaller animals offering multiple pregnancies at reduced cost but with shorter gestations. This paper describes operative techniques in the fetal rabbit and its advantages as a fetal surgical model. Experience with the pregnant rabbit has shown it to be a suitable surgical model for several reasons. Pregnancies are multiple, increasing cost effectiveness and permitting operation on up to eight fetuses per litter without fetal loss. Techniques that promote fetal survival include local housing of does several days prior to operation and preoperative sedation. Spontaneous mask ventilation provides ease of anesthetic administration and titration. Overall surgery is well tolerated with a low incidence of intraoperative complications. Rabbit models have been used in the study of transamniotic fetal feeding, abdominal wall defects, and wound healing. These techniques have resulted in postoperative fetal viability approaching 90%, with negligible maternal mortality in over 4000 fetal operations, thereby making the rabbit a manageable cost-effective model of fetal surgery.

Animals↗

PubMed1990

Clinical spectrum of symptomatic external iliac fibromuscular dysplasia.

External iliac fibromuscular dysplasia is a rare and usually asymptomatic disorder. We report eight symptomatic patients seen over a 15-year period and review pathophysiologic mechanisms accounting for the three following distinct lower extremity ischemic sequelae: (1) Emboli--episodic focal digital ischemia (blue toe) was seen in three patients. Resection and primary anastomosis of focal iliac ulcerative fibromuscular dysplasia (one patient) or resection and replacement (two patients) removed the embolic source and relieved the symptoms. (2) Chronic ischemia--gradual onset of full leg claudication in four patients was treated by operative graduated intraluminal dilation in three patients and prosthetic bypass in one. Arteriography subsequently showed a remodeled lumen in the three patients who underwent dilation. (3) Dissection--acute onset leg ischemia resulted from presumed dissection of the external iliac segment. After 4 months of conservative management of antiplatelet agents and exercise, symptoms resolved completely, and arteriogram showed spontaneous restoration of a normal lumen in the dissected segment. The clinical presentation of fibromuscular dysplasia may mimic other arterial processes such as atherosclerosis. Diagnosis is made only by arteriography with specific magnification views of the external iliac arteries and careful surveillance of the renal arteries. Appropriate treatment should be tailored to the clinical presenting symptom. For microembolic disease, resection and replacement are required. For chronic ischemia, intraluminal dilation is generally sufficient and durable and has proved to be a simpler and acceptable alternative to replacement or bypass. In acute dissection, surgical intervention may be deferred if the limb is viable to allow spontaneous healing and remodeling. Persistent symptoms may be the only indication for intervention in this ischemic manifestation of external iliac fibromuscular dysplasia.

Aged↗

PubMed1990

Infrarenal aortic occlusion: does it threaten renal perfusion or function?

Proximal propagation of aortic thrombus with resultant impaired renal perfusion has been considered a significant risk of untreated infrarenal aortic occlusion. To investigate this question, we studied 52 patients surviving 1 year or more after surgical interruption of the infrarenal aorta in the course of treatment of aortic graft infection. Blood pressure, renal function, and renal artery anatomy were studied before and after aortic interruption. Preoperatively, 20 patients (38.4%) had treated hypertension, and 11 (21.2%) had impaired renal function (creatinine greater than 1.3 mg/dl). In 46 patients (88.4%) with angiography before aortic interruption, 31 (67.4%) had normal renal arteries, whereas 15 (32.6%) demonstrated renal artery stenosis of less than or equal to 50% (N = 10) or greater than 50% (N = 9). Concomitant renal revascularization (N = 3) or nephrectomy (N = 1) were rare. All patients were monitored after surgery for a mean period of 39.2 months. Thirty-three (63.5%) remain alive and well; 19 (36.5%) have died of causes not related (N = 15) or indirectly related (N = 4) to the original graft infection. Forty-eight patients (92.3%) had late assessment of their blood pressure (N = 44, mean follow-up of 31.0 months) and/or renal function (creatinine) (N = 42, mean follow-up of 26.1 months). Follow-up aortography in 21 patients (40.4%, mean interval of 27.7 months) demonstrated no instance of suprarenal propagation of aortic thrombus. During follow-up 41 patients (78.8%) had no change in either their blood pressure or serum creatinine. Seven patients (13.5%) developed worsening hypertension (N = 3) or a rising creatinine (N = 4).(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta, Abdominal↗

PubMed1989

The treatment of achalasia. A current perspective.

We analyzed the course of 79 adult patients treated for achalasia between 1977 and 1988. Sixty-six patients (84%) had pneumatic dilatation as the primary therapy. Fifty-three patients (80%) had immediate improvement in swallowing. Three patients required immediate redilatation, 2 developed pulmonary aspiration, and 8 (12%) suffered esophageal perforation. Esophageal perforation was treated by closure plus Heller's myotomy in 3 patients, closure only in 3, chest tube in 1, and antibiotics and nasogastric suction in 1. At 4 years' follow-up, 50% of patients who had dilatation remained asymptomatic, 30% had symptoms of gastroesophageal reflux, and 20% had persistent dysphagia. Eight Heller myotomies were performed, with excellent results in 7 and 1 postoperative death from respiratory failure. Seven additional patients with disabling esophageal symptoms after multiple operations for achalasia were ultimately treated by esophagectomy (n = 5), hemigastrectomy and Roux-en-Y gastrojejunostomy (n = 1), and repeated myotomy (n = 1). All recovered and are able to eat solid food. Thus, our experience indicates that pneumatic dilatation remains unperfected (ie, the line between undertreatment and overtreatment is finer than generally recognized), and unless improvements can be made, the role for surgery may need to be reexpanded.

Adult↗

PubMed1989

Neonatal model of heterotopic heart transplantation in pigs.

To investigate the long-term success of heart transplantation in newborn infants who have complex congenital heart disease, we have developed a model of heterotopic heart transplantation in immature pigs. We chose the heterotopic technique because it is simple, does not require cardiopulmonary bypass or heparin, allows for significant size disparity between the recipient and donor hearts, and allows for experimental comparisons between the two hearts. Small newborn piglet hearts are harvested, prepared, and then transplanted into the left chest of larger weanling pigs to augment or substitute for the native left ventricle. Preliminary data from transplants into 49 pigs suggest that the technique is technically possible, the pigs can be immunosuppressed over the long term, and the donor heart can contribute hemodynamically. Experimentally, the model is well designed for the investigation of issues critical for the long-term success of heart transplantation in infants and children, including growth and development, optimal long-term immunosuppression, differences in immunotolerance, and the study of coronary obliterative disease. Clinically, the model has potential applicability in congenital heart anomalies if one native functioning atrium and ventricle are present.

Animals↗

PubMed1987

Long-term percutaneous biliary drainage in an infant with hemangioendothelioma.

A 5-month-old female infant with jaundice (bilirubin = 11) and dilated intrahepatic and extrahepatic bile ducts was explored. A 3-cm mass in the head of the pancreas and portal region completely obstructed the cystic and common bile ducts. Cholecystectomy was done and biopsy of the tumor and regional nodes revealed hemangioendothelioma with no nodal involvement. After tissue diagnosis was made, the infant's biliary tract was decompressed percutaneously. External drainage was maintained for 22 months until the tumor regressed. This infant is the youngest patient ever reported to undergo percutaneous biliary drainage.

Catheters, Indwelling↗

PubMed1987

Does an expanding fetal abdominal mass produce pulmonary hypoplasia?

Fetal pulmonary hypoplasia has been related to multiple factors. In an effort to define which fetuses may benefit from prenatal intervention to prevent or reverse pulmonary hypoplasia, we studied the relative contribution of an enlarging abdominal mass in the fetus. We produced abdominal masses in fetal rabbits at 24 days gestation by two methods. In one group, a small cylindrical chip of Takasen, (a synthetic polymer that expands to 50 times its size in 1 week; Grobeast, Pop Art Co, Cleveland, OH) was inserted into the peritoneal cavity of the fetal rabbit; in another group, the bladder neck was obstructed with a surgical clip. Amniotic fluid volume was restored at the surgical procedure. Sham-operated littermates served as controls. At cesarean delivery on day 30, fetal lung, liver, and body weights were measured, and the abdominal masses were quantitated by volume displacement of the removed mass or bladder. In both groups large abdominal masses of comparable size were produced. Newborns with the synthetic abdominal mass did not have significant pulmonary hypoplasia, but often had a prune belly deformity of the abdominal wall, whereas newborns with bladder obstruction had significant pulmonary hypoplasia. Liver weight was not significantly affected. We conclude that a fetal abdominal mass does not independently produce pulmonary hypoplasia, possibly because the "mass effect" is relieved by distension of the abdominal wall rather than elevation of the diaphragm; the pulmonary hypoplasia that occurs in bladder outlet obstruction is probably due to the associated oligohydramnios rather than the mass effect of the dilated urinary tract; and prenatal decompression of an abdominal mass or dilated urinary tract is not justified to prevent pulmonary hypoplasia in the absence of oligohydramnios.

Abdomen↗

PubMed1987

Auxiliary transplantation of the fetal liver. II. Functional evaluation of an intraabdominal model.

To evaluate the use of the fetal liver as an auxiliary graft, we have developed a model of intraabdominal heterotopic transplantation of late gestational fetal lamb livers into weanling lambs. Thirty-eight transplants have been performed of which 31 were technically successful. Twenty-three grafts functioned for intervals of 5 to 22 days after transplantation. Grafts were functionally evaluated by analysis of total bile acid and bilirubin excretion. To determine whether host liver excretory function would influence function of the graft, common bile duct ligated recipients were compared with recipients with normal host liver function. We found that (1) intraabdominal auxiliary transplantation of the fetal lamb liver is technically feasible; (2) the fetal liver graft is capable of rapid adaptation and can assume a significant portion of host excretory function; and (3) excretory function of the fetal liver is proportional to the functional demands of the host. Auxiliary transplantation of the fetal liver is a promising alternative to current methods of liver transplantation.

Abdomen↗

PubMed1986

Ureteropelvic junction obstruction in the fetus.

Ureteropelvic junction (UPJ) obstruction is being detected with increasing frequency before birth. To clarify the natural history of fetal UPJ obstruction, we reviewed our experience managing 28 fetuses; there were 16 bilateral cases for a total of 44 renal units. None required decompression before birth. We found that fetal bilateral UPJ obstruction is associated with significant morbidity and mortality; resolution of fetal hydronephrosis secondary to UPJ obstruction is rare; antenatal diagnosis of UPJ obstruction improves clinical management by allowing early detection and appropriate treatment of otherwise clinically undetectable disease; oligohydramnios in the mature fetus with bilateral UPJ obstruction is an indication for early delivery and immediate repair; and prenatally diagnosed UPJ obstructions should be repaired as early as possible after birth.

Abortion, Therapeutic↗

PubMed1969