Search PubMed⌕ Search

Biomedical subjects

W D Hager

Publications and source records attributed to W D Hager.

At least 37 records · Page 2Linked to original sources

Efficacy of oral antibiotics following parenteral antibiotics for serious infections in obstetrics and gynecology.

Patients with serious soft-tissue infections in obstetrics and gynecology are frequently treated with parenteral antibiotics until afebrile and clinically well for 48-72 hours, and then discharged on a broad-spectrum oral antibiotic. To evaluate the efficacy of this type of management, we designed a prospective, randomized single-blinded study comparing a group of patients who received oral antibiotics after hospital discharge (N = 80) with a group who did not (N = 83). No significant differences in age, race, parity, diagnosis, or pathogen isolated were observed between the patients in the two groups. No significant difference was noted in delayed morbidity between those who did and those who did not take oral antibiotics (P greater than .06). In light of the cost of oral antibiotics and the chance of drug-induced side effects, the data suggest that oral antibiotics after parenteral antibiotics are not indicated.

Administration, Oral↗

The effects of the long-acting angiotensin-converting enzyme inhibitor cilazapril on casual, exercise, and ambulatory blood pressure.

We assessed blood pressure (BP) and heart rate (HR) responses in a double-blind, randomized study comparing cilazapril, a long-acting, nonsulfhydryl-group converting enzyme inhibitor, with placebo in 18 patients with mild to moderate (sitting diastolic BP, 95 to 114 mm Hg) essential hypertension. The BP and HR parameters were evaluated at rest (casual, 24 hours after administration), during treadmill exercise testing (Bruce protocol), and with 24-hour noninvasive ambulatory BP monitoring. These assessments were made after a 4-week drug washout period and after 8 to 12 weeks of therapy. After 8 weeks of therapy with cilazapril (mean dose 3.6 +/- 0.9 mg/day), casual BP decreased 19/11 mm Hg (p less than 0.01), whereas placebo lowered BP by 4/5 mm Hg (difference not significant) compared with the baseline period. The casual HR was modestly (7 beats/min) but significantly (p less than 0.05) lowered by cilazapril monotherapy. Exercise BP was reduced by cilazapril (reduction at peak HR, 23/11 +/- 10/5 mm Hg; p less than 0.05), and exercise HR was unchanged. Compared with baseline, the duration of exercise was improved with cilazapril but not with placebo (1.0 minute vs -0.2 minute; p less than 0.05). Twenty-four-hour mean, awake, and sleep BPs were reduced with cilazapril with the most impressive reduction occurring during the awake period (19/12 mm Hg; p less than 0.01). These data demonstrate that cilazapril lowers casual, exercise, and ambulatory BP with a modest but significant improvement in exercise time. Thus cilazapril may be particularly effective in the physically active hypertensive patient.

Adult↗

Effects of chronic cetamolol therapy on resting, ambulatory, and exercise blood pressure and heart rate.

We studied blood pressure (BP) and heart rate (HR) responses in 12 patients with hypertension who were receiving cetamolol, a cardioselective beta-blocker with intrinsic sympathomimetic activity. The BP and HR parameters were evaluated at rest (casual, office readings), with ambulatory BP monitoring, and after treadmill exercise testing. At a mean (+/- SD) dose of 46 +/- 21 mg/day, casual supine BP decreased by 10/12 mm Hg (P less than 0.05 for systolic; P less than 0.01 for diastolic) compared with placebo, while HR decreased 4 bpm. Cetamolol resulted in a significant reduction in the mean 24-hour systolic BP. The most striking reduction occurred in the BP at work (23 mm Hg), with almost no decrease in the BP during sleep. Ambulatory HR reductions occurred while the subjects were at work (9 bpm; P less than 0.05) but not while at home (awake) or during sleep. The mean duration of exercise was the same during cetamolol and placebo phases, but both HR and BP fell significantly at peak performance after cetamolol. These data suggest that cetamolol reduces BP without lowering HR at rest. During periods of increased adrenergic activity such as work and dynamic exercise, both HR and BP are reduced.

Acetamides↗

Comparison of single-dose moxalactam and a three-dose regimen of cefoxitin for prophylaxis in vaginal hysterectomy.

In patients undergoing vaginal hysterectomy, prophylactic use of a single dose of moxalactam was compared with use of a standard three-dose regimen of cefoxitin for efficacy and for rate of postoperative colonization of the vaginal cuff with resistant bacteria. In a prospective, randomized study, patients hospitalized for vaginal hysterectomy received either cefoxitin sodium 2 g intramuscularly on call to the operating room followed by 2 g intravenously every six hours for two additional doses or a single dose of moxalactam disodium 2 g intramuscularly on call. Cultures of the meatal area and of urine were obtained preoperatively; postoperatively, cultures of urine, of the vaginal cuff, and of any site or fluid presumed to be infected were obtained. Data were evaluated for 38 patients in the moxalactam group and 40 patients in the cefoxitin group. There was no significant difference in the incidence of infectious morbidity (7.5% of cefoxitin-treated patients and 10.5% of moxalactam-treated patients). Infectious morbidity was not related to age, length of surgery, or estimated blood loss. The incidence of febrile morbidity was not significantly different (7.5% of the cefoxitin group and 13.2% of the moxalactam group). Colonization of the vaginal cuff with resistant organisms occurred in 70% of cefoxitin patients and 71% of moxalactam patients and was a poor predictor of infectious morbidity. In these 78 women undergoing vaginal hysterectomy, single-dose moxalactam and a three-dose regimen of cefoxitin were equally effective for surgical prophylaxis.

Adult↗

Successful management of varicella pneumonia complicating pregnancy. A report of three cases.

Although varicella is a common infection in the United States, pregnant women are infrequently infected. Varicella pneumonia is an even rarer though potentially fatal complication during pregnancy. Fulminant respiratory collapse often ensues and is associated with greater than 40% mortality. We successfully treated three patients for varicella pneumonia in pregnancy. Critical points of management include prompt diagnosis of the disease and recognition of the complications, rapid transfer to a facility capable of providing intensive care (including ventilatory support) and early initiation of aggressive antiviral chemotherapy.

Adult↗

Cellular actions and pharmacology of calcium-channel blockers.

The calcium-channel blockers represent a diverse group of chemical structures that block calcium-selective channels in the plasma membrane of a variety of excitable cells. As the calcium fluxes carried by these channels allow ionic calcium (Ca2+) to gain access to the cell interior, where Ca2+ serves as an activator--messenger, calcium-channel blockers generally act to inhibit cell function. By reducing the depolarizing currents caused by the entry of positively charged Ca2+ into the negatively charged interior of resting cells, the calcium-channel blockers also inhibit excitatory processes that depend on calcium entry across the plasma membrane. These principles account for most of the effects of calcium-channel blockers on the cardiovascular system. In vivo, the calcium-channel blockers inhibit contractile function in the heart and vascular smooth muscle and, because the initial depolarizing currents in the sinoatrial and atrioventricular nodes are carried by calcium channels, slow the heart rate and prolong atrioventricular conduction. However, in vivo in human studies, there are differences among the calcium-channel blockers. The vasodilatory effects of the calcium channel blockers, which can reduce systemic blood pressure, offer a primary basis for their potential use in the treatment of hypertension. The tissue specificity exhibited by some of the calcium-channel blockers may enhance their therapeutic value in selected hypertensive patients. Of the three calcium-channel blockers now available for use in the United States (diltiazem, nifedipine, and verapamil), diltiazem and verapamil are approximately equipotent in inhibiting calcium-channel function in cardiac and vascular smooth muscle, whereas nifedipine is more potent in vascular smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗

Unusual presentation of DDD pacemaker system malfunction.

A DDD pacemaker utilizing an atrial J electrode was implanted in a patient whose right atrial appendage had been removed 7 years prior during aortic valve replacement. Alternating QRS morphologies produced by pacemaker stimulus artifacts occurred as a consequence of atrial lead dislodgement. The screw-in atrial electrode has superior stability in patients with right atrial appendage removal; stability of the atrial J electrode cannot be obtained in such cases.

Electrocardiography↗

Fetal tachycardia as an indicator of maternal and neonatal morbidity.

Presented is a prospective, controlled study to determine if intrapartum fetal tachycardia is reliable as an indicator of maternal and fetal infectious morbidity. Thirty neonates with defined intrapartum tachycardia were matched by gestational age and weight with 30 control subjects without defined tachycardia. There was a significant difference in maternal febrile morbidity and a trend toward a difference in maternal infectious morbidity between the two groups. There was no significant difference in maternal complications at delivery or administration of antibiotics to the mother. Among the neonates, there was a significant difference in administration of antibiotics and the incidence of respiratory distress syndrome (RDS) between the two groups; however, both of these were significantly related to birth weight. There was no significant difference between the two groups in duration of ruptured membranes, duration of labor, number of vaginal examinations, or antepartum anemia. Only one study infant had a bacteremia. The data confirm an increased risk of neonatal complications, such as RDS, asphyxia, and meconium aspiration, in association with intrapartum fetal tachycardia.

Anti-Bacterial Agents↗

Cellular actions and pharmacology of the calcium channel blocking drugs.

The calcium channel blockers represent a group of diverse chemical structures that block calcium-selective channels in the plasma membranes of a variety of excitable cells. As the calcium fluxes carried by these channels allow the calcium ion (Ca2+) to gain access to the cell interior, where calcium serves as an activator messenger, calcium channel blockers generally act to inhibit cell function. By reducing the depolarizing currents caused by the entry of positively charged Ca2+ into the negatively charged interior of resting cells, the calcium channel blockers also inhibit excitatory processes that depend on calcium entry across the plasma membrane. These principles account for most of the effects of calcium channel blockers on the cardiovascular system. The calcium channel blockers inhibit contractile function in the heart and vascular smooth muscle and, because the initial depolarizing currents in the sinoatrial and atrioventricular nodes are carried by calcium channels, slow the heart rate and prolong atrioventricular conduction. The negative inotropic and vasodilatory effects of the calcium channel blockers, both of which can reduce systemic blood pressure, offer a theoretic basis for their potential use in the treatment of hypertension. The tissue specificity exhibited by some of the calcium channel blockers may enhance their therapeutic value in selected hypertensive patients. Of the three calcium channel blockers now available for use in the United States (diltiazem, nifedipine, and verapamil), diltiazem and verapamil are approximately equipotent in inhibiting calcium channel function in the heart and vascular smooth muscle, whereas nifedipine is more potent in smooth muscle. This tissue specificity can be used to advantage in the management of hypertension. These pharmacologic principles underlie the growing appreciation of the potential value of the calcium channel blockers in the treatment of hypertension.

Action Potentials↗

Digoxin-quinidine-spironolactone interaction.

Digoxin kinetics are substantially altered by quinidine and by spironolactone. We evaluated the effect of the combination of quinidine and spironolactone on digoxin kinetics and compared it to the effect on digoxin of each drug alone. Six normal subjects each received a 1.0-mg intravenous dose of digoxin alone, digoxin with quinidine, digoxin with spironolactone, and digoxin with both quinidine and spironolactone. Spironolactone and quinidine, alone and in combination, reduced digoxin systemic, renal, and nonrenal clearances and prolonged digoxin elimination t 1/2. A greater alteration in digoxin kinetics was induced by quinidine than by spironolactone, and an even greater effect resulted from the combination. We did not assess clinical consequences of the interaction. We advise reduction in digoxin dose, careful clinical evaluation, and measurement of serum digoxin concentrations when digoxin is used in combination with quinidine and spironolactone.

Adult↗

Beta blockers: the extended family.

Beta-Adrenergic blocking drugs, by occupying beta receptors without stimulating adenylate cyclase, interfere with the physiologic responses mediated by the sympathetic nervous system. This property has led to their application in the cardiovascular disorders on which sympathetic tone either underlies or contributes to the pathogenesis of the process. Lipid solubility, selective beta-receptor blockade, and intrinsic sympathomimetic activity are three additional characteristics of beta blockers that modify the pharmacodynamics and pharmacologic effects of each agent. As the role of the sympathetic nervous system in the pathogenesis of heart disease is better defined, the development of beta blockers with particular pharmacologic profiles and fewer side effects may provide more specific treatment.

Adrenergic beta-Agonists↗

Management of chorioamnionitis.

Chorioamnionitis presents as a serious threat to both mother and fetus. We have evaluated the diagnostic criteria and method of management by means of a retrospective analysis. Ninety-nine per cent of mothers had two of three major risk factors: 1, rupture of membranes; 2, leukocytosis of greater than 15,000, and 3, temperature greater than 100.4 degrees F. All three risk factors were present in 82.7 per cent. The method of management included culturing the endocervix when premature rupture of the membranes was present, administering parenteral antibiotics once the diagnosis of chorioamnionitis was made and performing cesarean sections for obstetric indications only. This management protocol resulted in a perinatal survival rate of 94.9 per cent in infants weighing more than 1,000 grams compared with 98.3 per cent in the general population and no perinatal deaths in infants weighing more than 1,500 grams. There were no maternal deaths. Our data support the recommendations that endocervical cultures be obtained for all patients with premature rupture of membranes, mothers with ROM and normal temperature and white blood cell count be managed without antibiotics, mothers with a diagnosis of chorioamnionitis have induction of labor and cesarean section be performed for obstetric indications only.

Adolescent↗

Conversion of atrial fibrillation to sinus rhythm by acute intravenous procainamide infusion.

We evaluated the efficacy of an intravenous infusion of procainamide in 26 consecutive candidates for cardioversion of atrial fibrillation. Procainamide was administered at a rate of 15 to 20 mg/min up to a maximum of 1000 mg. The treatment was considered effective only if cardioversion occurred during the procainamide infusion. Conversion to sinus rhythm occurred in 15 patients. Converters had a significantly shorter mean duration of atrial fibrillation (6 +/- 7 days, mean +/- S.D.) compared to nonconverters (79 +/- 88 days) (p less than 0.01). The mean left atrial size of converters (4.3 +/- 0.6 cm) did not differ significantly from that of nonconverters (4.7 +/- 0.9 cm). The dose of procainamide required for cardioversion ranged from 3.6 to 16.4 mg/kg. Two patients developed nonsustained ventricular tachycardia, and there was one episode of bifascicular block during the infusion. Intravenous procainamide is an effective form of therapy for conversion of atrial fibrillation of new onset.

Adult↗

Effect of the ouabain-quinidine interaction on left ventricular and left atrial function in conscious dogs.

The effect of the ouabain-quinidine interaction was examined in 10 conscious dogs. Left ventricular (LV) pressure, LV dP/dt, LV diameter and left atrial (LA) diameter were measured with high-fidelity micromanometers and sonomicrometer crystals. Ouabain, 0.025 mg/kg, significantly (p less than 0.05) increased LV dP/dt, LV and LA fractional shortening and LV and LA velocity of circumferential fiber shortening (Vcf). In a separate experiment, quinidine was administered as a bolus dose, 3.85 mg/kg, followed by an infusion, 0.28 mg/kg/min. This resulted in steady-state quinidine concentrations that produced no change in wall motion or hemodynamics. When ouabain was given 1 hour into the quinidine infusion, only LV dP/dt increased significantly (p less than 0.05). Ouabain alone increased LV dP/dt 26.4 +/- 3.5%, whereas ouabain during the quinidine infusion increased it by 9.5 +/- 2.3%. Similar differences were seen in the responses to ouabain in the absence and presence of quinidine: LV Vcf, 22.4 +/- 4.9% vs 6.0 +/- 2.1%, LV fractional shortening, 23.1 +/- 4.6% vs 5.8 +/- 2.1%, LA Vcf, 22.7 +/- 5.9 vs 4.6 +/- 2.0% and LA fractional shortening, 21.8 +/- 7% vs 7.8 +/- 3.3%. Thus, in the presence of quinidine the increase in intropy usually seen with ouabain was markedly attenuated. These data suggest that the quinidine-induced increase in digoxin serum concentrations is accompanied by a decrease in the contractile response of the heart to digoxin.

Animals↗

Treatment of serious obstetric and gynecologic infections with cefoxitin.

In order to evaluate the efficacy of cefoxitin, 25 patients with serious pelvic infections admitted to a community hospital were treated with the drug. Twenty-one patients (84%) responded to this therapy. Three of the four failures (75%) had a pelvic abscess. Resistant organisms included Staphylococcus aureus, Pseudomonas aeruginosa and enterococci. The adverse reactions encountered were due to localized phlebitis, which occurred in three patients (12%). The study demonstrated that cefoxitin was successful as a single agent in the treatment of serious soft-tissue pelvic infections.

Adult↗