Gunnar Blumenstock

Development of Cerebral Blood Flow Volume in Preterm Neonates during the First Two Weeks of Life

To investigate the postnatal development of cerebral perfusion in preterm neonates with normal brains over the first 2 wk of life, a prospective longitudinal study was designed. Quantitative measurement of cerebral blood flow (CBF) volume was performed using ultrasound flowmetry of the extracranial, brain-feeding arteries in 32 preterm infants of 28–35 wk gestational age. Measurements were done in the internal carotid and vertebral arteries of both sides on d 1, 2, 3, 7, and 14 after birth. A 10.0-MHz linear transducer of a computed sonography system (Acuson 128/XP10) was used. Intravascular flow volumes were calculated as the product of angle-corrected time-averaged flow velocity and the cross-sectional area of the vessel. Mean CBF volume increased markedly over the first 2 wk. One-third of this rise already occurred from the first to the second postnatal day, thereafter there was a continuous increase from d 2 to d 14 of life. Whereas the absolute level of CBF volume was primarily determined by postmenstrual age, the pattern of postnatal changes in CBF volume was found to be independent of gestational age. Arterial carbon dioxide tension, mean arterial blood pressure, and hematocrit had no influence on the development of CBF volume. The pronounced increase of CBF volume from d 1 to d 2 is likely to represent a normal adaptive response of the cerebral circulation to postnatal life. The data presented here may serve as the basis for further studies to investigate whether deviations from this adaptive response are associated with an increased risk of brain injury.

Quality of life after unilateral acoustic neuroma surgery via middle cranial fossa approach

Conclusions Patients with acoustic neuroma experienced reduced quality of life (QOL) after surgery. Individual factors did not have a significant effect on QOL. In the future, QOL should be a basic factor in the outcome evaluation of different therapeutic regimens in the treatment of acoustic neuroma. Objective To measure the QOL of patients who underwent unilateral acoustic neuroma surgery via the middle cranial fossa approach. Material and methods The Short Form-36 (SF-36) Health Survey and a self-designed disease-specific questionnaire were used during follow-up examinations to assess health-related QOL. The pure-tone average was used to specify hearing ability. Facial nerve function was described using the House–Brackmann grading system. A total of 28 male and 14 female patients who underwent surgery between 1997 and 2001 were included in the study. Results Patients’ QOL scores revealed significant reductions in QOL in comparison to normative German QOL data. Gender, age, tumor size or location and clinical symptoms such as hearing loss and restricted facial nerve function did not have an effect on QOL. The SF-36 scales physical functioning, role functioning—physical, bodily pain, general health, social functioning and role functioning—emotional demonstrated significant QOL reductions.

Comparison of Four Microwave Ablation Devices: An Experimental Study in ex Vivo Bovine Liver

PURPOSE To compare volume, sphericity, and short-axis diameter of the coagulation zone of four commercially available microwave ablation systems with three technical concepts in an ex vivo setting and to formulate mathematical models to predict these quantities. MATERIALS AND METHODS Two high-power systems (systems A and B), a system that enables simultaneous use of three antennas (system C), and a non-perfusion-cooled system that automatically adapts power and frequency (system D) were tested in ex vivo bovine livers (108 ablations). Coagulation volume, sphericity, and mean short-axis diameter were assessed, and mathematical functions were fitted for each system and assessed with the coefficient of determination (R(2)). Analysis of variance and Tukey post hoc tests were used for interdevice comparison after 5 and 10 minutes and after maximum recommended ablation time. RESULTS Volume and short-axis diameter were determined by using a mathematical model for every system, with coefficients of determination of 0.75-0.98 and 0.70-0.97, respectively. Correlation for determination of sphericity was lower (R(2) = 0.01-0.68). Mean results with ablation performed according to manufacturer recommendations were as follows: Volume, sphericity, and short-axis diameter were 57.5 cm(3), 0.75, and 43.4 mm, respectively, for system A; 72.3 cm(3), 0.68, and 45.5 mm, respectively, for system B; 17.1 cm(3), 0.58, and 26.8 mm, respectively, for system C (one antenna); 76.5 cm(3), 0.89, and 50.6 mm, respectively, for system C (three antennas); and 56.0 cm(3), 0.64, and 40.9 mm, respectively, for system D. Systems A (mean volume, 52.4 cm(3) ± 4.5 [standard deviation]) and B (39.4 cm(3) ± 1.7) reach large ablation zones with 5-minute ablation. CONCLUSION The largest ablation zone is obtained with systems B and C (three antennas) under maximum recommended ablation duration and with system A under short ablation time. The most spherical zone is obtained with system C (three antennas).

Nasal high–flow oxygen therapy in patients with hypoxic respiratory failure: effect on functional and subjective respiratory parameters compared to conventional oxygen therapy and non-invasive ventilation (NIV)

BackgroundAim of the study was to compare the short-term effects of oxygen therapy via a high-flow nasal cannula (HFNC) on functional and subjective respiratory parameters in patients with acute hypoxic respiratory failure in comparison to non-invasive ventilation (NIV) and standard treatment via a Venturi mask.MethodsFourteen patients with acute hypoxic respiratory failure were treated with HFNC (FiO2 0.6, gas flow 55 l/min), NIV (FiO2 0.6, PEEP 5 cm H2O Hg, tidal volume 6–8 ml/kg ideal body weight,) and Venturi mask (FiO2 0.6, oxygen flow 15 l/min,) in a randomized order for 30 min each. Data collection included objective respiratory and circulatory parameters as well as a subjective rating of dyspnea and discomfort by the patients on a 10-point scale. In a final interview, all three methods were comparatively evaluated by each patient using a scale from 1 (=very good) to 6 (=failed) and the patients were asked to choose one method for further treatment.ResultsPaO2 was highest under NIV (129 ± 38 mmHg) compared to HFNC (101 ± 34 mmHg, p <0.01 vs. NIV) and VM (85 ± 21 mmHg, p <0.001 vs. NIV, p <0.01 vs. HFNC, ANOVA). All other functional parameters showed no relevant differences. In contrast, dyspnea was significantly better using a HFNC (2.9 ± 2.1, 10-point Borg scale) compared to NIV (5.0 ± 3.3, p <0.05), whereas dyspnea rating under HFNC and VM (3.3 ± 2.3) was not significantly different. A similar pattern was found when patients rated their overall discomfort on the 10 point scale: HFNC 2.7 ± 1.8, VM 3.1 ± 2.8 (ns vs. HFNC), NIV 5.4 ± 3.1 (p <0.05 vs. HFNC). In the final evaluation patients gave the best ratings to HFNC 2.3 ± 1.4, followed by VM 3.2 ± 1.7 (ns vs. HFNC) and NIV 4.5 ± 1.7 (p <0.01 vs. HFNC and p <0.05 vs. VM). For further treatment 10 patients chose HFNC, three VM and one NIV.ConclusionsIn hypoxic respiratory failure HFNC offers a good balance between oxygenation and comfort compared to NIV and Venturi mask and seems to be well tolerated by patients.Trial registrationGerman clinical trials register: DRKS00005132.

Prognostic value and therapeutic consequences of vascular invasion in non-small cell lung carcinoma

The prognostic relevance of blood vessel invasion (BVI) in non-small cell lung carcinoma (NSCLC) remains controversial, as is the question of whether its finding should influence therapeutic decisions after an R0 resection. One hundred and twelve cases of NSCLC were included in the study. All had been treated by potentially curative surgical resection of the primary tumor and systematic lymphadenectomy. In all cases, lymphatic metastatic spread was at its earliest stage and only one regional lymph node was involved, 27.0+/-8.9 nodes per patient being examined histologically. Most of the cases were pT2 (75.9%) and pN1 (81.3%), and all were MX/M0 and R0. 62.5% were at stage IIB, 25.9% at stage IIIA, and 9.8% at stage IIA. BVI was found in 45.5% of the tumors (V1), and 18.8% exhibited both lymphatic invasion and BVI (L1V1). Local recurrence occurred in 10.7% of the patients, distant metastasis in 24.1%, and both forms of tumor progression simultaneously in a further 7.1%. Thus 31.2% of the patients developed distant metastases by hematogenous spread (to the brain, bones, lung, adrenal, and liver, in descending order of frequency), mostly within two years of surgery. Late metastasis is not typical of NSCLC. Adenocarcinomas showed a strong tendency to be associated with a poorer prognosis than squamous cell carcinomas, probably because of their more frequent involvement of blood vessels. Five-year survival (Kaplan-Meier method) was significantly lower in V1 cases (37.2%) than in V0 cases (56.0%; p = 0.0249). Adjuvant mediastinal radiation in node-positive cases of NSCLC may prevent local recurrence but is unlikely to influence the development of distant metastases. The histological detection of BVI is of prognostic relevance and should be considered for inclusion in the staging criteria and indications for adjuvant chemotherapy.

Treatment efficiency, outcome and surgical treatment problems in patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma: a report from the Cooperative Soft Tissue Sarcoma trial CWS-96.

To analyze the clinical course, treatment modalities, complications and outcome of patients suffering from localized embryonal bladder/prostate rhabdomyosarcoma (BPRMS) treated on the CWS‐96 trial.

Point-of-Care Testing of Coagulation in Patients Treated With Non–Vitamin K Antagonist Oral Anticoagulants

Background and Purpose— Specific coagulation assays for non–vitamin K antagonist oral anticoagulants (NOAC) are relatively slow and often lack availability. Although specific point-of-care tests (POCT) are currently not available, NOAC are known to affect established coagulation POCT. This study aimed at determining the diagnostic accuracy of the CoaguChek POCT to rule out relevant concentrations of rivaroxaban, apixaban, and dabigatran in real-life patients. Methods— We consecutively enrolled 60 ischemic stroke patients newly started on NOAC treatment and obtained blood samples at 6 prespecified time points. Samples were tested using the CoaguChek POCT, laboratory-based coagulation assays (prothrombin time and activated partial thromboplastin time, anti-Xa test and Hemoclot), and liquid chromatography–tandem mass spectrometry for direct determination of NOAC concentrations. Results— Three hundred fifty-six blood samples were collected. The CoaguChek POCT strongly correlated (r=0.82 P<0.001) with rivaroxaban concentrations but did not accurately detect dabigatran or apixaban. If used to estimate the presence of low rivaroxaban concentrations, POCT was superior to predictions based on normal prothrombin time and activated partial thromboplastin time values even if sensitive reagents were used. POCT-results ⩽1.0 predicted rivaroxaban concentrations <32 and <100 ng/mL with a specificity of 90% and 96%, respectively. Conclusions— If anti-Xa test is not available, we propose the use of the CoaguChek POCT to guide thrombolysis decisions after individual risk assessment in rivaroxaban-treated patients having acute ischemic stroke. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT02371044.

Perioperative Outcome of Patients with Esophageal Atresia and Tracheo-esophageal Fistula Undergoing Open Versus Thoracoscopic Surgery

INTRODUCTION Thoracoscopic approach for repair of esophageal atresia (EA) and tracheo-esophageal fistula (TEF) has become a standard procedure in many pediatric surgical centers. Thoracoscopic surgery in a newborn is demanding from both the surgeon and the patient. The potential benefits for the newborn are still discussed by neonatologists, pediatric intensive care physicians, and also parents. The aim of our investigation was to clearly define perioperative outcome and complication rates in children undergoing thoracoscopic versus open surgery for EA and TEF repair. PATIENTS AND METHODS We reviewed the records of 68 newborns undergoing surgery for EA and TEF between March 2002 and February 2010. Patient data of open versus thoracoscopic approach were compared regarding operating time, intraoperative as well as postoperative pCO(2)max values, postoperative ventilation time, and complications. Specific patient data are reported with the median and range. Data analysis was done with the JMP(®) 7.0.2 statistical software (SAS Institute, Cary, NC). RESULTS For the 68 patients, the mean gestational age was 35 weeks (28-41), the median birth weight was 2720 g (1500-3510 g) in the thoracoscopic group and 2090 g (780-3340 g) in the open group. There were 36 girls and 32 boys. Thirty-two children had associated anomalies. Twenty-five children were undergoing a thoracoscopic procedure. In 8 cases, the operation was converted to open thoracotomy. Another 32 children received a thoracotomy. In 11 newborns, a cervical esophagostomy was performed because of long-gap EA and these patients were excluded from the study. Operating time was 141 minutes (77-201 minutes) in the thoracoscopic group and 106 minutes (48-264 minutes) in the thoracotomy group, with significant difference (P=.014). Values of pCO(2)max during operation were 62 mm Hg (34-101 mm Hg) in the thoracoscopic group and 48 mm Hg (28-89 mm Hg) in the open group, with significant difference (P=.014). Postoperative ventilation time was 3 days (1-51 days) in all groups, with no significant difference (P=.79). Early complications were noticed in 9 children undergoing thoracoscopy and in 8 patients of the thoracotomy group, again with no significant difference (P>.05). CONCLUSION Thoracoscopic repair of EA with TEF is justified because of a comparable perioperative outcome to open surgery, competitive operating times, decreased trauma to the thoracic cavity, and improved cosmesis despite skeptical considerations. Complication rates are not higher than in children operated on through a thoracotomy. However, a learning curve has to be taken into account and large experience in minimal invasive surgery is mandatory for this procedure. Larger series have to be expected for a more objective evaluation of perioperative as well as long-term outcomes. To our opinion, the thoracoscopic approach appears to be favorable and could be a future standard.

Rational Approach to the Diagnosis of Severe Growth Hormone Deficiency in the Newborn

CONTEXT Severe congenital GH deficiency (GHD) of the newborn is a rare disease, which can cause life-threatening hypoglycemias beginning in the first week of life. Reviews and consensus papers on the diagnosis of GHD repeatedly state the lack of a practical evidence-based approach to the diagnosis of GHD in the newborn. OBJECTIVE Here we provide for the first time sound reference values and a diagnostic cutoff for the GH levels in newborns at the age between d 3 and 5. DESIGN, SETTING, AND PATIENTS GH was measured in the eluate from 314 filter papers of the newborn screening test performed in our university hospital by using a highly sensitive human GH-ELISA. Reference data are compared with measurements from nine newborns with very high likelihood of having severe GHD, and cutoffs for the diagnostic work-up are defined. RESULTS In the presence of clinical evidence, the diagnosis of neonatal GHD can be confirmed during the first week of life by a single randomly taken GH level less than 7 microg/liter with 100% sensitivity and 98% specificity on the basis of our assay method. GH content in newborn screening cards stored for almost 3 yr were not different from the content found in recently used screening cards indicating high immunological stability of GH over time. Therefore, the diagnostic approach can use stored screening cards. In addition, we observed a clear gender dichotomy in respect to GH, with healthy female newborns having significantly higher GH levels than males. Cigarette smoking during pregnancy was associated with higher, transient tachypnea of the newborn with lower GH levels. CONCLUSIONS We provide the first rational approach to the diagnosis of severe GHD in the newborn and evidence for gender dichotomy of the neonatal GH axis.

Laparoscopic Surgery on Upper Urinary Tract in Children Younger Than 1 Year: Technical Aspects and Functional Outcome

PURPOSE Minimally invasive procedures are increasingly important in pediatric urology. However, experience is still limited with minimally invasive operations on the upper urinary tract in infants. We analyzed 3 minimally invasive procedures (pyeloplasty, heminephroureterectomy and nephrectomy) in children younger than 1 year. MATERIALS AND METHODS We analyzed 67 children (mean +/- SD age 5.1 +/- 2.9 months) undergoing minimally invasive pyeloplasty in 26 patients (group 1), heminephroureterectomy in 18 (group 2) or nephrectomy in 23 (group 3) with regard to technical aspects, surgical outcome and complications. Preoperative and postoperative ultrasound and mercaptoacetyltriglycine renal scan were statistically evaluated in groups 1 and 2. RESULTS Mean +/- SD patient weight was 6.4 +/- 1.8 kg and mean +/- SD operative time was 113.2 +/- 41.6 minutes. Conversion to open surgery was necessary in 1 pyeloplasty. One complication (missed intraoperative bowel perforation) occurred. No blood transfusion was required in any child. After pyeloplasty there were improved tracer clearances (mercaptoacetyltriglycine scan) and improved morphologies of the pyelon (ultrasound) in all patients. In groups 1 and 2 there was no statistical difference between preoperative and postoperative partial function of the affected kidney. Mean +/- SD followup was 32.5 +/- 19.8 months. CONCLUSIONS Minimally invasive procedures on the upper urinary tract in children younger than 1 year are technically challenging, and require expertise of the surgeon and the entire team. Given these assumptions, such procedures can be safely performed with excellent functional outcomes.