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W Gogarten

Publications and source records attributed to W Gogarten.

At least 19 recordsLinked to original sources
PubMed2006

The excor device - revival of an old system with excellent results.

OBJECTIVE: We report on our experience with the BerlinHeart Excor system in adults and paediatric patients who underwent placement of the mechanical support device under emergency conditions and demonstrate the exceptional advantages and the considerable versatility of the system. METHODS: Since 2003, 29 consecutive patients (25 adults and 4 infants) with ages ranging from 10 months to 54 years underwent implantation of an Excor system. Main underlying heart diseases in adults were acute myocardial infarction (n = 9), dilative cardiomyopathy (n = 6), acute myocarditis (n = 6), whereas most of the children suffered from dilative cardiomyopathy. Ten patients had undergone implantation of an extracorporeal membrane oxygenation system. RESULTS: In 26 cases, a left ventricular assist device (LVAD) was implanted, while 3 patients had biventricular support. The support interval of all patients surviving the perioperative period lasted from 30 to 412 days, mean period of support until heart transplantation or explantation was 184 +/- 117 days. Severe complications were rare. CONCLUSION: The Excor paracorporeal mechanical support system is an excellent and highly versatile device for the support of patients of all ages and different types of underlying heart disease in the mid-term and long-term. The implant procedure and the perioperative management are simple, and complication rates are low.

Adolescent↗
PubMed2005

Assessment of volume preload on uteroplacental blood flow during epidural anaesthesia for Caesarean section.

BACKGROUND AND OBJECTIVE: Epidural and spinal anaesthesia are the preferred mode of anaesthesia for Caesarean section. Volume preloading is recommended to prevent maternal hypotension and a reduction in uteroplacental blood flow, although positive effects of volume preloading on maternal cardiac output and arterial pressure are debatable. Doppler measurements of the umbilical artery beyond deriving pulsatility indices are not routinely performed. METHODS: After Institutional Review Board approval and written informed consent, 14 consecutiVe women with epidural anaesthesia for Caesarean section received either hydroxyethyl starch 500 mL or gelatine 500 mL. Haemodynamic variables monitored were maternal arterial pressure, maximal blood flow velocity and pulsatility indices of the uterine artery derived from Doppler measurements. CONCLUSIONS: Maternal arterial pressure and pulsatility indices in both groups did not change from baseline after intravenous colloid infusion. However, uterine blood flow increased significantly in both groups. The effectiveness of volume preloading may therefore be better described by changes in maximum uterine blood flow velocity than by pulsatility indices or maternal arterial pressure.

Adult↗
PubMed2005

[Current concepts in neuraxial anaesthesia for labour and delivery].

Epidural analgesia for labour has been associated with an increased rate of motor blockade, and instrumental and Caesarean deliveries. In recent years, these risks were significantly reduced with modern concepts of epidural analgesia, including the use of lower doses of local anaesthetics in combination with opioids. With combinations of 0.0625-0.125 % of bupivacaine plus sufentanil or fentanyl, the incidence of maternal motor blockade approximates 10 % and most parturients are nowadays able to ambulate during labour. Methods of epidural drug administration consist of intermittent boluses, patient-controlled epidural analgesia (PCEA) or continuous infusions. While intermittent top-ups and PCEA do not differ in the amount of local anaesthetics used, continuous infusions have been associated with increases in drug consumption and motor blockade in addition to a higher workload (e. g. frequent adjustments of infusion rates). They therefore do not appear to confer significant benefits during labour analgesia. The most common type of anaesthesia for Caesarean delivery is spinal anaesthesia due to its simplicity, cost-effectiveness and speed of onset. It is suitable for cases of an urgent or emergent Caesarean delivery. General anaesthesia still leads to a higher maternal mortality and should be reserved for absolute emergencies and cases where neuraxial blockade is contraindicated.

Analgesia, Epidural↗
PubMed2004

[Venous thromboembolism prophylaxis].

Venous thromboembolism is a common and frequent complication of hospitalized patients. Some venous thromboembolisms may be subclinical, while others present as symptomatic deep vein thrombosis and/or pulmonary embolism. Venous thromboembolism and pulmonary embolism contribute significantly to inhospital morbidity and mortality. The risk of venous thromboembolism is aggravated by dispositional and/or expositional risk factors. In patients at intermediate or high risk of venous thromboembolism, additional pharmacological thromboembolism prophylaxis becomes mandatory.

Anesthesia↗
PubMed2004

A multicentre trial comparing different concentrations of ropivacaine plus sufentanil with bupivacaine plus sufentanil for patient-controlled epidural analgesia in labour.

BACKGROUND AND OBJECTIVE: To determine the optimal concentration of ropivacaine for bolus-only patient-controlled epidural labour analgesia, three different doses of ropivacaine were evaluated in comparison with bupivacaine in a double-blinded multicentre study. METHODS: Four hundred-and-fifty labouring parturients at term in three different academic institutions were randomized to four groups receiving bupivacaine 0.125% with sufentanil 0.75 microg mL(-1), ropivacaine 0.125% or 0.175% with sufentanil 0.75 microg mL(-1), or ropivacaine 0.2%. After an initial bolus of 10 mL of the study solution, and once visual analogue scores (VAS) were below 30 mm, patient-controlled epidural analgesia was initiated with a bolus of 4 mL, a lockout interval of 15 min and without a background infusion. Variables studied were the quality of analgesia, incidence of side-effects, the degree of motor blockade, and the mode of delivery. RESULTS: Bupivacaine 0.125% and ropivacaine 0.125% with sufentanil proved equally effective in providing labour analgesia without a difference in local anaesthetic consumption (48.6 +/- 23 mg bupivacaine vs. 52.1 +/- 38 mg ropivacaine), motor blockade or mode of delivery. Ropivacaine 0.175% plus sufentanil enhanced the quality of analgesia of the initial loading dose, whereas ropivacaine 0.2% without sufentanil increased the consumption of local anaesthetics (80.2 +/- 34 mg; P < 0.05) and the degree of motor blockade. CONCLUSION: Despite recent studies indicating that bupivacaine and ropivacaine may not be equipotent, both local anaesthetics provided equi-effective analgesia at equal doses without a difference in side-effects.

Abdominal Muscles↗
PubMed2002

Stability of a sufentanil-ropivacaine mixture in a glass and a PVC reservoir.

BACKGROUND AND OBJECTIVE: Drug mixtures containing sufentanil may be unstable owing to absorption into the drug reservoirs of patient-controlled epidural analgesia systems that contain polyvinylchloride. The stability of sufentanil in a mixture of ropivacaine 0.2% in a 750 mL reservoir was therefore investigated. METHODS: During simulated epidural infusions of 5 mLh(-1) at 25 degrees C, sufentanil concentrations were measured for 96 h. Samples were taken from the reservoir and from the end of the epidural catheter under the following conditions: into glass or polyvinylchloride reservoirs containing ropivacaine 0.2% with sufentanil 1, 0.75 or 0.5 microg mL(-1); and into polyvinylchloride reservoirs with ropivacaine 0.2% and sufentanil 1 microg mL(-1) which were stored for 4 weeks at 8 degrees C. RESULTS: The different solutions remained stable over the observation period of 96 h. Using the same solutions, independent samples' ANOVA showed no difference in the sufentanil concentrations between the glass and polyvinylchloride reservoirs, or between the polyvinylchloride reservoirs when stored for 4 weeks. Correlations between the concentrations at the different measurement times were extremely high for the reservoir (r(min) = 0.98, r(max) = 1.00) and the catheter end (rmin = 0.86, r(max) = 1.00). CONCLUSIONS: Sufentanil citrate at 0.5-1.0 microg mL(-1) in an admixture of ropivacaine 0.29 for 5 days, which is the usual period for postoperative epidural analgesia, remains stable in a polyvinylchloride reservoir. There is no change in the drug concentration even if the reservoir is stored for 4 weeks at 8 degrees C.

Amides↗
PubMed2001

Oxytocin and lysophosphatidic acid induce stress fiber formation in human myometrial cells via a pathway involving Rho-kinase.

The actin cytoskeleton is important for stress fiber formation and contributes to the initiation and maintenance of smooth muscle contraction. To determine if oxytocin and lysophosphatidic acid (LPA) induce stress fiber formation, cultured human myometrial cells were exposed to oxytocin (10(-5) M) or LPA (10(-6) M), and filamentous (F) and globular (G) actin pools were stained with fluorescein isothiocyanate-phalloidin and Texas red DNase I, respectively. The F- to G-actin fluorescent-staining ratio was measured by fluorescence microscopy. Oxytocin and LPA increased stress fiber formation, as indicated by an increase in the F- to G-actin fluorescent-staining ratio. The Rho-kinase inhibitor Y-27632 markedly attenuated this increase. Oxytocin-induced stress fiber formation was completely inhibited in the presence of the oxytocin antagonist compound VI. Tyrosine kinase inhibition with tyrphostin A23 partially blocked the increase induced by oxytocin but had no effect on LPA-induced stress fiber formation. Stress fiber formation was not blocked by pertussis toxin, mitogen-activated protein kinase, or protein kinase C inhibitors. Our results show that human myometrial cells respond to oxytocin and LPA with the formation of stress fibers that may be involved in the maintenance of uterine contractions. Rho-kinase appears to be a key signaling factor in this pathway.

Actins↗
PubMed2000

Operative techniques and strategies for minimally invasive fetoscopic fetal cardiac interventions in sheep.

BACKGROUND: Recent efforts to develop procedures for fetoscopic fetal cardiac interventions have been prompted by the development of severe secondary damage to the fetal heart due to semilunar valvar obstructions and the poor outcome of therapy-refractory fetal arrhythmias. The purpose of our manuscript is to analyze and share our experience with the creation of an operative setup for these procedures in sheep. METHODS: We studied a total of 48 fetal sheep between 81 and 106 days of gestation (term, 145 days). After entering the amniotic cavity by a percutaneous approach, we performed various fetoscopic fetal cardiac procedures. We analyzed the success of percutaneous fetal access, methods of trocar support, the incidence and management of trocar dislodgement or accidental insertion into the chorioamniotic space, problems related to amniotic insufflation and trocar placement, as well as techniques for fetal posturing and uterine closure. RESULTS: Percutaneous fetal access was achieved in all sheep. The use of resterilizable trocars substantially decreased the costs of our procedures. Utilizing a percutaneous transuterine purse-string suture for trocar support helped to minimize the number of nonabsorbable T-fasteners remaining inside the uterus postoperatively. As complications such as trocar dislodgement, insertion of the trocar into the chorioamniotic space, and problems with intraamniotic insufflation and gas loss were mastered, conversion to an open operative approach was never required. A novel strategy that we devised for percutaneous fetal posturing permitted adequate fetal posturing with ease and minimal trauma to the fetal skin. CONCLUSION: As operative techniques have become more refined, the feasibility of performing fetoscopic fetal cardiac interventions in human fetuses now depends mainly on technical improvements in imaging and interventional catheters, as well as advances in pacemaker equipment.

Animals↗
PubMed2000

Fetal surgery: general or regional anaesthesia?

Major improvements in the diagnosis and treatment of fetal malformations, including in-utero surgical repair, have occurred in the past decade. As opposed to anaesthesia for caesarean sections, a high placental drug transfer is warranted to provide adequate fetal anaesthesia and immobility, strongly favouring the use of general anaesthesia for these cases. Even though the question of fetal pain perception is still debated, studies suggest that attenuation of the fetal stress response can improve outcome. Other major concerns include the maintenance of uterine blood flow and uterine relaxation, as premature labour and delivery severely limit fetal benefits from surgery. When performing these procedures, physicians have a special responsibility to weigh maternal risks against fetal benefits and should not jeopardize the life of the mother for procedures with questionable fetal outcome.

Journal Article↗
PubMed1999

Fetoscopic transesophageal electrocardiography and stimulation in fetal sheep: a minimally invasive approach aimed at diagnosis and termination of therapy-refractory supraventricular tachycardias in human fetuses.

BACKGROUND: Therapy-refractory supraventricular tachycardia commonly results in hydrops and death in human fetuses. The purpose of this study in fetal sheep was to assess the feasibility of a minimally invasive fetoscopic approach for fetal transesophageal electrocardiography and stimulation aimed at diagnosis and termination of these tachycardias. METHODS AND RESULTS: We studied a total of 10 fetal sheep (87 to 103 days of gestation; term=145 days). We entered the amniotic cavity using a percutaneous fetoscopic approach and placed various electrophysiology catheters into the fetal esophagus. We recorded the number of animals in which fetoscopic transesophageal electrocardiography and stimulation were successful and assessed pacing success and thresholds for different catheters. In addition, we monitored for potential adverse effects from stimulation and for other complications of the operation. Recording of transesophageal electrocardiograms was successful in all fetal sheep. Capture during stimulation was successfully documented by additional fetal bipolar surface electrocardiograms in 7 fetuses. In fetuses in which fetal surface electrocardiograms were not recorded, pacing stimulus artifacts interfered with documentation of capture. Although stimulation thresholds were high, the maternal rhythm was not affected by fetal stimulation. CONCLUSIONS: Fetoscopic fetal transesophageal electrocardiography and stimulation are feasible in fetal sheep. This minimally invasive approach might have the potential to improve diagnosis and management of therapy-refractory supraventricular tachycardias in human fetuses.

Animals↗
PubMed1998

Haemodynamic effects of repeated epidural test-doses of adrenaline in the chronic maternal-fetal sheep preparation.

A randomized crossover study was designed using the chronically instrumented pregnant sheep preparation to study the possible effects of epidural injection of adrenaline as a single compound on the circulation of mother and fetus. Three consecutive identical doses of adrenaline were administered epidurally with a 30 min interval between treatments. In a randomized crossover fashion two dosages (10 and 15 micrograms) were tested on different days. The day after the last epidural experiment the same doses of adrenaline were given intravenously (i.v.). Between the two i.v. doses a 30 min interval was allowed for values to return to baseline. Twenty-seven experiments were performed in eight ewes. Epidural administration of adrenaline did not affect maternal mean arterial pressure, maternal heart rate, uterine blood flow, fetal mean arterial pressure, fetal heat rate, or maternal and fetal blood gases and acid-base status. After i.v. administration of adrenaline the uterine blood flow decreased in a dose-dependent fashion, but the other haemodynamic variables were not affected. In conclusion, this study indicates that consecutive epidural injections of adrenaline have no significant effect on maternal and fetal haemodynamic responses, uterine blood flow, blood gases and acid-base status in the gravid ewe. However, an i.v. injection of 10 or 15 micrograms adrenaline decreases the uterine blood flow and could compromise the fetus.

Acid-Base Equilibrium↗
PubMed1998

The effects of adding isoproterenol to 0.125% bupivacaine on the quality and duration of epidural analgesia in laboring parturients.

UNLABELLED: This study was conducted to determine the effects of adding isoproterenol to epidural bupivacaine and sufentanil on the quality and duration of analgesia during labor. In a double blind, randomized study, 80 women were divided into two groups, receiving three doses of 0.125% bupivacaine with 7.5 microg of sufentanil and either 12.5 microg of epinephrine (EPI group) or 5 microg of isoproterenol (ISO group). Contraction pain was measured using a 100-mm visual analog scale (VAS) before epidural analgesia, at 5-min intervals for 15 min after each epidural injection, and hourly thereafter. Overall, no significant differences were observed in VAS scores between the groups. However, in the ISO group, VAS scores at 10 and 15 min after the first and second administration were significantly lower than those in the EPI group. Analgesia after each administration lasted significantly longer in patients who received epinephrine. Because of the limited duration of analgesia in the ISO group, more patients in this group received a fourth epidural administration of 0.125% bupivacaine with epinephrine 1:800,000. In conclusion, the addition of isoproterenol to bupivacaine and sufentanil induces a faster onset of analgesia and reduces the duration of analgesia compared with bupivacaine with sufentanil and epinephrine. Therefore, it is preferable to use isoproterenol only once, as a test dose, after the placement of the epidural catheter. IMPLICATIONS: We analyzed the quality and duration of analgesia in laboring women after they received bupivacaine and sufentanil combined with isoproterenol or epinephrine epidurally. We found that the addition of isoproterenol to bupivacaine and sufentanil induces a faster onset of analgesia and reduces the duration of analgesia.

Adrenergic beta-Agonists↗
PubMed1998

A case of severe cerebral trauma in a patient under chronic treatment with cyclosporine A.

A case of severe cerebral head injury in a child, chronically treated with cyclosporine A after orthotopic liver transplantation, is presented. The initial Glasgow Coma Scale score after the motor vehicle accident was 3, and computed tomography showed multiple sites of intracerebral bleeding, an epidural hematoma, and signs of perifocal edema. Although these lesions are normally associated with a poor outcome, the child recovered unexpectedly well. In brain injury, a lucid interval can be followed by secondary neurologic deterioration due to a loss of high-energy metabolites, a release of neurotransmitters, and an increase in intracellular Ca2+. These events finally led to cell damage in the penumbra of an ischemic infarction. Among other drugs, immunosuppressants such as cyclosporine A have been shown to exhibit neuroprotective properties in experimental models if given during this time interval of secondary neurologic deterioration. Although human data on these effects are still lacking, we conclude that neuroprotective actions of cyclosporine A may have been involved in the favorable outcome in this 14-year-old boy.

Adolescent↗