Biomedical subjects

F Lam

Publications and source records attributed to F Lam.

24 records · Page 2Linked to original sources

PubMed1988

Use of the subcutaneous terbutaline pump for long-term tocolysis.

Nine patients in preterm labor requiring long-term tocolysis were managed with subcutaneous terbutaline administered via a portable infusion pump. All had failed oral tocolytic therapy and were therefore faced with prolonged hospitalization. In this feasibility study, the patients were treated at home and monitored with portable tocodynamometers and home nursing visits. Uterine activity data were transmitted via telephone to the study center and terbutaline pump infusion rates were adjusted accordingly. Terbutaline pump therapy consisted of a combination of low-dose continuous basal infusion supplemented with intermittent high-dose boluses. Total daily drug dosage remained exceptionally low (less than 3 mg/24 hours). The mean gestational age at initiation of therapy was 29.6 +/- 3.7 weeks, and pregnancy was prolonged an average of 9.2 +/- 4.3 weeks. The minimum gestational age at delivery was 37.3 weeks. Patient tolerance was excellent and, in a total 394 patient-days of therapy, there were no significant complications. We conclude that the portable subcutaneous terbutaline pump may be a promising new method for long-term outpatient tocolysis in patients who cannot be maintained on oral therapy.

Administration, Oral↗

PubMed1986

Failure to demonstrate decreased beta-adrenergic receptor concentration or decreased agonist efficacy in term or preterm human parturition.

Iodine 125-labeled iodocyanopindolol, a radioactive beta-adrenergic antagonist, bound to particulate preparations of pregnant human myometrium in a manner compatible with binding to the beta-adrenergic receptor. Studies with a specific beta 2-antagonist, IPS 339, indicated that 72% of receptors present were of the beta 2-subtype. Quantitative studies of beta-receptor concentrations in myometrium from women at term indicated no change in receptor concentration during labor. Similarly, there was no difference in beta-receptor concentration in myometrium from women in labor or before labor between 28 and 34 weeks of gestation. Concentrations of the beta-receptor were not different at any stage of gestation assayed. Isoproterenol competition for iodocyanopindolol binding was used to examine efficacy of receptor agonist interactions in myometrium from women at term, in labor, or before labor and from women in preterm labor. There was no difference in high-affinity binding, an index of efficacy, in any of the groups examined.

Adrenergic beta-Agonists↗

PubMed1976

The ultrastructure of the cells of Leydig in the white-crowned sparrow (Zonotrichia leucophrys gambelii) in relation to plasma levels of luteinizing hormone and testosterone.

In male White-crowned Sparrows subjected to 20 h daily photoperiods there is an approximately 3-fold increase in the plasma concentration of luteinizing hormone (LH) on the first long day after which a quasi-stable level is maintained for at least 42 days. This increase is followed by an increase in numbers of cells of Leydig and an enhancement of their steroidogenic features, a decrease in transitional interstitial cells, and an increase in plasma level of testosterone. With the decline in plasma LH, as photorefractoriness develops, the steroidogenic features of the cells of Leydig undergo disorganization. For as yet unexplainable reasons the plasma levels of testosterone decline before the decrease in plasma LH and before the degeneration of the steroidogenic features of the cells of Leydig.

Animals↗

PubMedDate not supplied

Open repair of massive rotator cuff tears in patients aged sixty-five years or over: is it worthwhile?

The purpose of the study was to evaluate the functional outcome and identify possible preoperative prognostic factors in patients aged 65 years or over undergoing open repair for a massive (>5 cm) full-thickness rotator cuff tear. Patients were assessed after a mean of 48 months by an independent observer by use of the Constant score and the Oxford Shoulder Questionnaire. The outcome was excellent or good in 44% and poor in 23%. The patient satisfaction rate was 84%. Pain relief was obtained in 93%. We found three preoperative variables to be significantly associated with a poor outcome: female sex, duration of symptoms greater than 34 months before surgery, and American Society of Anesthesiologists grade. The results of our study suggest that appropriately selected patients who are aged 65 years or over with a massive full-thickness rotator cuff tear can be expected to have a good functional outcome and pain relief after repair.

Age Factors↗

PubMedDate not supplied

A comparison of gestational days gained with oral terbutaline versus continuous subcutaneous terbutaline in women with twin gestations.

OBJECTIVE: To compare gestational days gained with oral versus subcutaneous terbutaline for maintenance tocolysis. STUDY DESIGN: In retrospective fashion 386 women enrolled in an outpatient preterm labor identification program met the following criteria: twin gestation, development of threatened preterm labor resulting in treatment with oral terbutaline, and subsequent recurrence of threatened preterm labor resulting in treatment with continuous subcutaneous terbutaline. The primary outcome was gestational days gained with oral terbutaline versus gain with continuous subcutaneous terbutaline. RESULTS: There were significantly more days gained during subcutaneous treatment than during oral treatment (34.0 +/- 19.8 versus 19.3 +/- 15.3 days). Thirty-three percent of desired prolongation was achieved with oral terbutaline, whereas 79% of desired prolongation was achieved with subcutaneous terbutaline (p < 0.001). Patients gained a mean of 53.4 +/- 21.4 days overall with outpatient tocolysis. The mean gestational age at delivery was 35.2 +/- 1.9 weeks. CONCLUSION: Continuous subcutaneous terbutaline was superior to oral terbutaline in prolonging gestation in women with twin gestations.

Administration, Oral↗

PubMedDate not supplied

Clinical and cost-effectiveness of continuous subcutaneous terbutaline versus oral tocolytics for treatment of recurrent preterm labor in twin gestations.

OBJECTIVE: To compare the clinical and cost-effectiveness of treating recurrent preterm labor with continuous subcutaneous terbutaline versus oral tocolytics in twin gestations. STUDY DESIGN: In a retrospective, matched-cohort design, twin pregnancies treated as outpatients with continuous subcutaneous terbutaline were identified from a perinatal database, then matched 1:1 by gestational age at recurrent preterm labor to those receiving oral tocolytics. There were 353 patients per treatment group. A cost model was used to compare antepartum hospital, nursery, and outpatient charges. RESULTS: Infants of the subcutaneous terbutaline group had greater gestational age at delivery, higher birth weights, and less frequent neonatal intensive care unit admission. Charges for antepartum hospitalization and nursery were significantly less in the subcutaneous terbutaline group, while charges for outpatient services were less for the oral group. Mean total estimated charges were US$17,109 less for those receiving subcutaneous terbutaline. CONCLUSION: Improved clinical outcomes and decreased nursery utilization suggest cost-effectiveness of outpatient continuous subcutaneous terbutaline versus oral tocolytics for the treatment of recurrent preterm labor.

Administration, Oral↗