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Biomedical subjects

J D Baker

Publications and source records attributed to J D Baker.

At least 19 recordsLinked to original sources
PubMed1992

Antibody response to Bordetella pertussis antigens after immunization with American and Canadian whole-cell vaccines.

Because of apparent differences in the incidence and epidemiology of pertussis in the United States and Canada, we measured the antibody response to four Bordetella pertussis antigens and to a whole-bacteria preparation in children immunized with American and Canadian whole-cell pertussis vaccines. All infants received combined pertussis, tetanus, and diphtheria vaccines from one of two American manufacturers or a single Canadian manufacturer. The Canadian children received either oral poliomyelitis vaccine, inactivated poliomyelitis vaccine as a separate injection, or a product that combined inactivated poliomyelitis vaccine with diphtheria, tetanus, and pertussis components. The Canadian trivalent diphtheria, tetanus, and pertussis vaccine given with oral poliovirus vaccine induced lower anti-pertussis toxin antibody titers than did the American vaccines (p < or = to 0.05) but higher antifimbriae and anti-69-kilodalton outer-membrane protein (pertactin) antibody titers (p < or = to 0.02). Canadian children immunized with inactivated poliomyelitis vaccine either as a separate injection or as a combined diphtheria, tetanus, and pertussis vaccine had consistently lower pertussis antibody titers than did those who received oral poliomyelitis vaccine (p < or = 0.001). We conclude that there is a wide range of antibody responses to B. pertussis antigens after immunization with various whole-cell pertussis vaccines, and that these responses may be influenced by concurrent administration of other vaccines.

Antibodies, Bacterial↗
PubMed1992

Office probing of congenital nasolacrimal duct obstruction.

We report the results of office nasolacrimal duct probing under topical anesthesia in 2369 eyes with symptomatic nasolacrimal duct obstruction. The overall success rate for cure by initial probing was 92%. In patients less than 9 months old, a 94% cure rate was achieved with one probing; in patients 9 months and older, the rate decreased to 84%. The decrease in success rate after 9 months was statistically significant (P less than .00001 by chi-square analysis). A majority of 180 parents of these patients surveyed said they were happy with the office procedure and preferred having the probing performed to resolve symptoms, even though they realized that the symptoms most probably would resolve by 1 year of age without it. We conclude that office probing for congenital nasolacrimal duct obstruction is a safe and effective method for treatment of symptomatic nasolacrimal duct obstruction, allowing the cost and risk of general anesthesia as well as the cost and inconvenience of prolonged medical management to be avoided.

Age Factors↗
PubMed1992

Long-term results of infrainguinal revascularization with polytetrafluoroethylene: a ten-year experience.

Two hundred fifty-eight patients underwent 322 infrainguinal revascularizations with use of polytetrafluoroethylene (PTFE) between 1978 and 1988. The indication was limb salvage in 190 (59%) reconstructions. Two hundred nineteen (68%) were above-knee, and 75 (23%) were below-knee femoropopliteal bypasses. Twenty-eight (8.6%) were femoral-infrapopliteal bypasses, all done for limb salvage. Follow-up ranged from 24 to 144 months (mean, 66 months). The perioperative mortality rate (1 to 30 days) was 3.4% (9 patients), with no significant difference according to indication (2.9% vs 3.7%). Actuarial primary patency at 8 years for the entire series of femoropopliteal bypasses was 53% (above knee 53%; below knee 39%; p less than 0.05), and improved with additional procedures for a secondary patency of 72%. Femoropopliteal bypasses done for severe claudication had an 8-year actuarial primary patency of 63%, compared with 38% for limb salvage (p less than 0.02). Actuarial limb salvage in the latter group at 8 years was 66%. Femoral-infrapopliteal reconstructions with PTFE had a significantly lower primary patency at 3 years (22%, with a 37% limb salvage). Sixty-four percent of the failures for all reconstructions (N = 111) occurred within 12 months, with remarkable stabilization of patency curves beyond that interval. This experience represents the largest reported series of PTFE reconstruction with longest follow-up to date and may serve as a basis for comparison of other conduits. These results suggest an important role for PTFE in femoropopliteal revascularization and a limited role of this prosthetic conduit in femoral-infrapopliteal arterial reconstructions.

Adult↗
PubMed1991

Which asymptomatic patients should undergo routine screening carotid duplex scan?

The benefits of obtaining a routine screening carotid duplex scan have not been established for patients with peripheral vascular disease but no signs or symptoms of carotid artery disease. We retrospectively reviewed all carotid duplex scans (4,000) performed at our institution between 1985 through 1989 and found for analysis 91 scans in 78 patients who underwent a screening duplex scan because of the presence of peripheral vascular disease. Patients with carotid bruits, abnormal carotid pulses, and focal or nonspecific neurologic symptoms were excluded. Thirty-three percent of these patients had carotid stenosis of 16% to 50%, 14% had carotid stenosis greater than or equal to 50%, and 5% had stenosis greater than or equal to 75%. Individual risk factors for atherosclerosis, including elderly age, coronary artery disease, hypertension, diabetes, smoking, and a recent or past history of cardiac or vascular surgery, did not predict the detection of high-grade carotid stenosis. However, all 11 of the patients with carotid stenosis greater than or equal to 50% were 68 years of age and older, and this age range, in combination with the various risk factors, increased the incidence of significant carotid artery stenosis (greater than or equal to 50%) to as high as 45%. We conclude that routine screening carotid duplex scan is indicated in elderly patients (age greater than or equal to 68 years) with peripheral vascular disease, even in the absence of any signs or symptoms of carotid artery disease, when other atherosclerotic risk factors are present.

Adult↗
PubMed1991

Preoperative duplex scan assessment of the inferior epigastric artery as a coronary bypass conduit.

The inferior epigastric arteries are currently being evaluated as alternative autologous arterial conduits for coronary artery bypass operations. The inferior epigastric arteries are variable in diameter and length and require harvesting through separate abdominal incisions. There is a need, therefore, for a method to preoperatively assess the diameter and length of the inferior epigastric arteries to determine their suitability as a coronary artery bypass graft. We have found that the duplex scan is a valuable noninvasive preoperative imaging modality to evaluate the inferior epigastric arteries.

Abdominal Muscles↗
PubMed1991

The operating expense budget. One part of a manager's arsenal.

When budgets are submitted, the financial department must determine if expected revenues meet expected expenses. The cost of implementing new programs, capital purchases, and operating budget should be less than the overall revenue. If it is not, the manager must reduce the budgets. The manager identifies ways to reduce the supply costs and options for changing practice and systems. Collaborative effort is involved when physician practice must change to meet the budget reduction needs. A reduction in overall expenses is needed to initiate new programs and purchase requested equipment. To prepare and finalize the operating expense budget, the manager needs to foster quality improvement in services, employ negotiation skills, justify budget proposals, redistribute funds, and seek cost-saving methods.

Accounting↗
PubMed1991

Prevention of thromboembolic disease following total knee arthroplasty. Epidural versus general anesthesia.

Seventy-two patients were randomized into a prospective clinical trial to evaluate the effects of epidural (EA) versus general anesthesia (GA) on the incidence of thromboembolic disease (TED) following total knee arthroplasty (TKA). Males received aspirin 650 mg po bid and females low-dose warfarin daily to maintain the prothrombin time at 15 to 16 seconds for pharmacologic prophylaxis against TED. Thirty-four patients had EA and 38 GA for their primary TKA. Contrast venography and ventilation-perfusion scanning were performed on the sixth, seventh, and eighth postoperative days, and these were interpreted in a blinded fashion. The mean age of the 45 males and 27 females was 64 years (range, 42-84 years). There were no significant differences between the two groups with respect to hematocrit, operative time, blood loss, number of units transfused, or hospital stay. Twelve of the 34 patients (35%) receiving an EA and 10 of the 38 patients (26%) receiving GA developed TED, an overall incidence of 31% (p greater than 0.05) Fifty-three percent of the clots were located in the popliteal vein above the trifurcation or more proximal. However, the incidence of proximal vein thrombosis was significantly less in patients receiving an EA (46%) rather than a GA (64%). The incidence and distribution of clots was not affected by the type of pharmacologic prophylaxis, gender, or use of methylmethacrylate. Ten percent of the patients had a positive scan by strict criteria and were thought to have a pulmonary embolism (PE). In patients with a femoral vein clot, the incidence of PE was 67%. One bleeding complication occurred in a patient who took double the appropriate warfarin dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Assessment of peripheral arterial occlusive disease.

Many older patients in critical care settings have significant arterial disease, so the assessment of peripheral circulation may be important in their management. A great deal of information can be gained through the physical examination, which can be supplemented by the use of the Doppler velocity detector. This device should be used to obtain quantitative pressure measurements. Special consideration must be given to evaluation early in the postoperative period.

Angiography↗
PubMed1990

The medial rectus muscle insertion site in infantile esotropia.

The distance from the corneoscleral limbus to the insertion site of the medial rectus muscle was measured at several stages of medial rectus recession surgery in 20 patients (40 eyes) with infantile esotropia. Disinsertion of the medial rectus muscle resulted in a mean reduction in the distance from the muscle insertion site to the corneoscleral limbus of 0.903 mm (P less than .001), whereas the use of fixation forceps on the insertion to abduct the eye resulted in an additional mean reduction of 0.306 mm (P less than .01). The strabismus surgeon often uses the muscle insertion site as a reference point in determining the desired location for recessing a muscle. Our results suggest that this method of measurement is unreliable in infantile esotropia because the position of the medial rectus muscle insertion site varies considerably during surgery.

Child, Preschool↗
PubMed1990

Fetal Doppler shift waveforms in intrauterine growth retardation: laplace transform analysis technique.

An approach to the analysis of fetal blood flow velocity/time waveforms is described using a Doppler shift flowmeter. The waveform shape is described in terms of its Laplace transform. Variations in the value of the dominant coefficient in the Laplace transform in the descending thoracic aorta appear to distinguish growth retarded from normally grown fetuses early in pregnancy. Growth retardation was defined by an index of size specifically aimed at detecting the disproportionately grown fetus. Simpler methods of waveform shape description fail to detect the growth retarded fetus early in the second trimester.

Aorta, Abdominal↗
PubMed1990

Hemodynamic assessment of aortoiliac segment.

Routine noninvasive tests often fail to identify advanced aortoiliac stenosis, especially in cases with multilevel disease. At present, direct measurements of femoral artery pressure provide the best assessment of the hemodynamic effect of a proximal lesion, especially when flow is increased in order to simulate exercise. In the future, duplex scanning may replace invasive pressure studies.

Aorta, Abdominal↗
PubMed1990

A modification of the supraclavicular approach to the central circulation.

Traditional anterior or posterior triangle approaches to the central circulation may be at times unsuccessful in the patient whose anatomy makes cannulation difficult. We used a supraclavicular approach to cannulation of the central circulation in 100 patients for intraoperative monitoring or insertion of renal dialysis catheters. We have had only two failures, both in patients for dialysis catheter placement, and no complications. Review of the literature reveals a similar history of success with variations of this approach. The supraclavicular approach is an easy cannulation technique for the inexperienced physician and a useful alternative to traditional approaches for the experienced physician.

Catheterization, Central Venous↗