Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PATENTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,801 records · Page 100Linked to original sources

Fentanyl-air-oxygen anesthesia for ligation of patent ductus arteriosus in preterm infants.

In 10 premature infants (1123 +/- 263 g), fentanyl citrate (30 to 50 microgram/kg) was used in conjunction with pancuronium (0.1 mg/kg) as the sole anesthetic for transthoracic ligation of patent ductus arteriosus. Ventilation was controlled with air and oxygen in concentrations sufficient to maintain transcutaneous PO2 between 50 and 70 torr. Circulatory stability was easily maintained throughout the procedure. "Stiff chest" was avoided by the use of muscle relaxants, and the infants were awake within 1 hour after the procedure.

Air↗

Problem of patent ductus arteriosus in premature infants.

Postanatal closure of the ductus arteriosus depends on the level of O2 to which it is exposed. Certain vasoactive substances may also play a role in this constriction. The response to O2 is not as well developed in immature fetal animals and this probably explains the high incidence of patent ductus arteriosus (PDA) in premature human infants. The magnitude of shunting through a PDA depends on its size and the relationship between the pulmonary and systemic vascular resistances. Factors affecting the pulmonary vascular resistance (such as hypoxia) will therefore affect the shunt. The ability of the infant to handle the volume overload also depends on maturity of the infant since myocardial development may not be complete even at term. The clinical manifestations and management of PDA with and without pulmonary disease are described. Recent attempts at pharmacological closure of the PDA are presented.

Animals↗

Patent ductus arteriosus. Its occurrence with unequal pulmonary vascularity and hyperlucent left lung.

Twenty-four of 230 patients with patent ductus arteriosus had hypovascularity and hyperlucency in the left lung on preoperative chest roentgenograms. Two of the 24 patients died shortly after operation, and one was unavailable for follow-up. During the postoperative course (mean, three years), roentgenograms of eight of the remaining 21 patients showed persistent, unequal pulmonary vascularity and hyperlucent left lung, with no evidence of air trapping, and two patients had diminished volume of the hyperlucent left lung compared with that of the right lung.

Bronchography↗

A case of aortic septal defect, associated with patent ductus arteriosus and aberrant right subclavian artery.

This report describes an operation, successfully performed by the authors, on an aorta septal defect (A-P Window) associated with patent ductus arteriosus (PDA) and aberrant right subclavian artery (ARSA). When an A-O Window is complicated by PDA and ARSA, preoperative diagnosis is often difficult. It is often mistaken for a large PDA and ARSA. Therefore at the time of operation of a large PDA and ARSA, it is necessary tao keep artificial heart-lung machine ready so that the A-P Window can be corrected at the same operation if necessary. In this case, the aortopulmonary communication was closed directly by transpulmonary approach under profound hypothermia with extracorporeal circulation after the division of ductus arteriosus and the dissection and mobilization of the stenotic esophagus from surrounding tissues of the ARSA. The division of the ARSA was not carried out, because patient was asymptomatic. The A-P Window associated with PDA and ARSA has apparently not been reported.

Ductus Arteriosus, Patent↗

Patent ductus arteriosus with pulmonary hypertension in the dog.

The clinical, physiologic, and pathologic manifestations of patent ductus arteriosus (PDA) with pulmonary hypertension (right to left type PDA) were studied in 5 dogs. Cyanosis, hindlimb collapse, low-intensity heart murmurs, and splitting of the 2nd heart sound were prominent clinical findings. Secondary polycythemia was a feature in 3 dogs. Electrocardiography revealed marked frontal plane right axis deviation in all dogs. Radiographic findings in all dogs consisted of an enlarged right ventricle and main pulmonary artery segment, with a hypovascular pulmonary pattern. A wide descending aorta was evident in 4 dogs. Pulmonary arteriography revealed blunt, tortuous secondary and tertiary vessels. Blood flow through the PDA was from right to left in 4 dogs and bidirectional in 1. Necropsy of 1 dog revealed extensive pulmonary arterial disease characterized by fibromuscular intimal proliferation. Surgical correction was contraindicated, and medical therapy was not required in the 4 dogs retained by the owners as pets. Due to the persisting congenital heart defect and the real and potential sequelae, the prognosis is guarded.

Animals↗

A double blind study of the effects of oral indomethacin in preterm infants with patent ductus arteriosus who failed medical management.

Over a two year period, 52 infants were found to have clinical signs of patent ductus arteriosus (PDA). Twenty-seven responded to fluid restriction and furosemide; the remaining 25 infants entered the Indomethacin (IN) study protocol. Their mean (+/- SE) gestational age was 29.3 (+/- 0.6) weeks and birth weight was 1,142 (+/- 80) gm. Either a placebo or IN (0.25 mg/kg) orally was given for two doses, 24 hours apart; if no response occurred, the patient was crossed over to the opposite medication. Using Chi-square analysis, a significant response rate to IN was found. There were no significant differences in birth weights, gestational ages, or fluid intake between responders and nonresponders. However, both responders and nonresponders required a prolonged ventilator course, suggesting factors other than PDA causing prolonged ventilatory requirements in these babies.

Double-Blind Method↗

A comparison of oral and intravenous indomethacin dispositions in the premature infant with patent ductus arteriosus.

Plasma concentrations of indomethacin were studied in 18 premature infants exhibiting significant patent ductus arteriosus (sPDA) after either intravenous or oral drug administration. Oral absorption of indomethacin was prolonged and bioavailability, based on area under the curve (AUC), was less than 20%. The mean volume of distribution for indomethacin was 0.36 l/kg and showed only a small variation between subjects. The drug elimination half-life ranged from 10-25 hours and demonstrated a significant correlation with gestational age. There was no evidence to support dose-dependent clearance or enterohepatic circulation in this study. Side effects of indomethacin were limited in one infant. No significant changes were observed in hematocrit, platelet count, and serum creatinine. The results from this study support the continued use of intravenous sodium indomethacin trihydrate at doses of 0.2 mg/kg and intervals of 18-24 hours for pharmacological treatment of sPDA.

Administration, Oral↗

Patent ductus arteriosus in the dog: a retrospective study of radiographic, epidemiologic, and clinical findings.

Twenty-seven cases of patent ductus arteriosus (PDA) in the dog, which were confirmed by cardiac catheterization, surgical exploration, or at necropsy, were reviewed. A machinery murmur, electrocardiographic evidence of left ventricular enlargement, and radiographic evidence of cardiomegaly with an aortic and a pulmonary artery dilatation were consistent features. Surgical repair was successful in 65% of the dogs. The postoperative radiographic and electrocardiographic changes are described. A concomitant congenital defect was present in 2 dogs. The epidemiologic features of 532 dogs identified as having PDA and submitted to the National Cancer Institute's Veterinary Medical Data Program were reviewed. Miniature and Toy Poodles, Pomeranians, and Shetland Sheepdogs were identified as being at high risk for PDA. An excess of females over males was noticed.

Animals↗

Patent ductus arteriosus in infants of low birth weight.

Patent ductus arteriosus was diagnosed in 239 neonates of low birth weight (less than 2500 g) referred to the Hospital for Sick Children in a 21/2-year period. The respiratory distress syndrome was present in 77% of the group and congestive heart failure in 50%. Spontaneous closure of the defect was more frequent in those without congestive heart failure. In 48 patients whose heart failure could not be controlled by other medical therapy indomethacin was given, and in 20 (42%) it was judged successful. Surgical ligation of the ductus was performed at a median age of 30 days in 33 infants who either failed to respond to indomethacin or in whom its use was contraindicated; there were no intraoperative deaths, but 11 (33%) of the infants died 4 days to 6 months after the operation.

Ductus Arteriosus, Patent↗

The patent ductus arteriosus as a source of recurrent peripheral embolisations.

A patient with a multiple peripheral embolisation of unknown origin is presented. Because of her extreme obesity, some diagnostic procedures could not be performed (CAT), and some were performed with great difficulty (conventional ECHO, DSA of the aorta). Transesophageal echocardiography was the key procedure in the diagnosis of the floating thrombotic mass in the descending aorta. A surgical operation was performed, and a thrombus was found in the aortic orifice of the hemodynamically insignificant patent ductus arteriosus. The patient has now been 18 months in good condition and free of thromboembolic events.

Adult↗

Technology assessment of nonsurgical closure of patent ductus arteriosus: an evaluation of the clinical effectiveness and costs of a new medical device.

OBJECTIVE: To assess the clinical efficacy and cost impact of a new medical device for the nonsurgical closure of patent ductus arteriosus (PDA). METHODS: This was a before-after study comparing the most recent 20 surgical procedures with the first 20 nonsurgical procedures for PDA using a new medical device. Clinical outcome, hospital stay, device cost, and physician fees were compared. RESULTS: Surgical closure was effective in all 20 patients, with an average cost of $4667. In a similar patient group, nonsurgical closure was achieved in 18 of 20 patients (90%), with an estimated average cost per successful procedure of $4690. A clinically insignificant PDA leak persisted beyond 12 months in four nonsurgically managed patients. CONCLUSION: Nonsurgical closure of PDA can be recommended as an effective new medical technique that is not associated with a measurable increase in direct costs and that provides significant indirect and intangible cost advantages.

Cardiac Catheterization↗

[Closure of patent ductus arteriosus by video-thoracoscopy in 45 children].

For over 20 years, different methods of interventional catheterisation have partially replaced surgical closure of patent ductus arteriosus (PDA). The authors report the results of a new operative technique, video-thoracoscopy, derived from endoscopic surgery. Under general anaesthesia and after tracheal intubation, two trocarts of 5 mm diameter are introduced into the thorax for the passage of the instruments required for dissection and closure of the PDA. Two hooks are also introduced to retract the lung and dissect the ductal region. Two 9 mm titanium clips are positioned under videoscopic control. Forty-five children underwent this procedure between February 1992 and July 1994. The average age at the time of operation was 13.8 months (range: 3 to 32 months) with an average weight of 14.5 kg (range: 2 to 48 kg) including 10 (22%) with a body weight of less than 6 kg. The surgical indications were haemodynamic in 27% of cases (large shunts with pulmonary hypertension) and prophylactic against endocarditis in 73% of cases. There were no operative fatalities. The immediate complications included: chylothorax (1 case) and left recurrent nerve paralysis (2 cases). A residual shunt was observed in 3 of the 45 cases (6%). In one of these cases, a supplementary clip was effective in suppressing the residual shunt. In the other 2 cases, the residual shunt was respected after a second failure of clipping the duct in one of the cases. The final closure rate was 95.6%. Closure of PDA by video-thoracoscopy is a rapid and safe technique.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Treatment of patent ductus arteriosus by placement of intravascular coils in a pup.

A 3-month-old female mixed-breed pup was referred for evaluation and treatment of patent ductus arteriosus (PDA). Selective angiography was performed to confirm the diagnosis. A cone-shaped PDA with a large aortic base was outlined. A second selective angiographic procedure was performed to functionally close the PDA by use of thrombotic coils; complete obstruction was obtained. Twenty-four hours after the procedure, the murmur disappeared. One month later, the dog was reexamined and found to be clinically normal.

Angiography↗

Patent ductus arteriosus. Clinical relevance of prostaglandins and prostaglandin inhibitors in PDA pathophysiology and treatment.

This article presents a comprehensive review of the patent ductus arteriosus which so often affects the premature neonate. Included are a discussion of the unique anatomy and physiology of the ductus, a review of the mechanisms involved in normal closure, and factors leading to persistent patency. Various therapeutic options also are discussed, including some new and innovative approaches.

Ductus Arteriosus↗

[Transcutaneous transvenous occlusion of patent ductus arteriosus].

Transvenous closure is described of the patent ductus arteriosus with a conical device that consists of polyurethane foam mounted on a stainless steel flame. Since 1981, the procedure has been performed in 273 patients in Russia. Permanent complete ductus closure was achieved in 258 (95%) patients. In eight cases (3%), the occlusion was incomplete. Complications occurred in 10 patients (4%), seven of whom required emergency surgery. The new technique combines certain advantages of both alternative methods. The conical shape of the occlusion device is well suited for the anatomic structure of the ductus. The possibility of selecting the size of the device permits reduction in the rate of incomplete closure while still taking advantage of transvenous delivery to avoid entryside problems. In the initial 10 years of experience, the described technique proved effective, safe, and applicable in the vast majority of patients older than 2 years.

Adolescent↗

Relationship between hemodynamics and plasma atrial natriuretic peptide in children with ventricular septal defect or patent ductus arteriosus.

To evaluate the relationship between concentrations of ANP in plasma of the right-sided central circulation and hemodynamic parameters in congenital heart disease with left-to-right shunt. We enrolled 20 children aged from 1 month to 4.8 years with ventricular septal defect (VSD) or patent ductus arteriosus (PDA). The concentrations of ANP in plasma were extracted through a cartridge (Sep-Pak C18) before being measured by radioimmunoassay. Significant increased concentrations of ANP in plasma from inferior vena cava (117.6 +/- 18.1 pg/mL), right atrium (160.6 +/- 21.6 pg/mL) to pulmonary artery (PA) (253.4 +/- 38.8 pg/mL) were recognized. In VSD (n = 10) and PDA (n = 10), the concentrations of ANP in plasma from the inferior vena cava correlated significantly with the ratio of pulmonary to systemic blood flow (Qp/Qs) (r = 0.69, p < 0.05; r = 0.94, p < 0.01 respectively), the systolic pulmonary artery pressure (r = 0.90, p < 0.01; r = 0.93, p < 0.01 respectively), the diastolic pulmonary artery pressure (r = 0.76, p < 0.02; r = 0.68, p < 0.05 respectively), and the mean pulmonary artery pressure (r = 0.88, p < 0.01; r = 0.87, p < 0.01 respectively). The concentrations of ANP in plasma from the pulmonary artery also correlated significantly with the Qp/Qs (r = 0.81, p < 0.01; r = 0.87, p < 0.01 respectively). The results indicated that left atrial volume loading may have an important influence on secretion of ANP in some congenital heart disease with left to right shunt.

Atrial Natriuretic Factor↗

Examination of the early 'learning curve' for transcatheter closure of patent ductus arteriosus using the Rashkind occluder. PDA Closure Comparative Study Group.

BACKGROUND: Results of transcatheter implantation of the Rashkind double umbrella occluder for treatment of patent ductus arteriosus (PDA) have improved over time. We evaluated factors associated with changes in outcomes seen in the early clinical experience with this device. METHODS AND RESULTS: We reviewed records of otherwise healthy pediatric patients undergoing occluder implantation for isolated PDA between 1982 and 1987 at six major US and Canadian referral centers. Logistic regression was used to assess the impact of ductal size, patient age and weight, calendar time, prior intrainstitutional occluder experience, and residual center effects on closure rates. There were no study deaths. Of 180 occluder placement attempts, 76.7% (95% confidence limits = 70.5%, 83.0%) produced PDA closure by auscultation at 14-month cardiology follow-up or its equivalent. Success probabilities increased in a linear fashion as ductus size decreased, ranging from 41.7% for large (4.1 to 9.0-mm) ducts to 89.4% for small (1.5 to 2.5-mm) lesions. PDA occluder closure rates also improved over time, increasing from 47.4% in 1982-1983 to 84.6% in 1986 and 83.1% in 1987. Multivariate logistic regression indicated that improved outcomes were mainly attributable to decrease in the size of treated ducts over time. Independent of this patient selection, improvements in outcome were less strongly associated with cumulative intracenter experience, calendar time, and age. CONCLUSIONS: Increasing closure rates seen over time primarily reflected more judicious selection of patients as experience accumulated. However, other factors also contributed to the observed trends. An analysis of current treatment results would be of considerable interest.

Age Factors↗

Refine your search to explore more results.