Devrim Aksakal’s research while affiliated with Heidelberg University and other places

To review our institutional results and assess different surgical and non-surgical techniques for the treatment of displaced diametaphyseal forearm fractures in children and adolescents. Thirty-four children (25M, 9F) with a total of 36 diametaphyseal forearm fractures who underwent treatment under general anesthesia between July 2010 and February 2016 were recruited to this retrospective study. From October 2016 until March 2018 patients and/or parents were contacted by telephone and interviewed using a modified Pediatric Outcomes Data Collection Instrument (PODCI). Median age at the time of injury was 9.1 years (range, 1.9–14.6 years). Initial treatment included manipulation under anesthesia (MUA) and application of plaster of Paris (POP) (n = 9), elastic stable intramedullary nailing (ESIN) (n = 10), percutaneous insertion of at least one Kirschner wire (K-wire) (n = 16), and application of external fixation (n = 1). Eleven children (32%) experienced a total of 22 complications. Seven complications were considered as major, including delayed union (n = 1) and extensor pollicis longus (EPL) tendon injury (n = 1) following ESIN, as well as loss of reduction (n = 2) and refractures (n = 3) after MUA/POP. The median follow-up time was 28.8 months (range, 5.3–85.8 months). In 32 out of 34 cases (94%) patients and/or parents were contacted by telephone and a PODCI score was obtained. Patients who experienced complications in the course of treatment had a significantly lower score compared with those whose fracture healed without any sequelae (P = .001). There was a trend towards an unfavorable outcome following ESIN compared with K-wire fixation (P = .063), but not compared with POP (P = .553). No statistical significance was observed between children who were treated initially with a POP and those who had K-wire fixation (P = .216). There is no standard treatment for displaced pediatric diametaphyseal forearm fractures. Management with MUA/POP only is associated with an increased refracture rate. Based on our experience K-wire fixation including intramedullar positioning of at least one pin seems to be favorable compared with ESIN.

Background: Our previous work in a laparoscopic setting in piglets revealed that the systolic femoral artery pressure was approximately 5 % higher than its carotid counterpart, whereas the mean and diastolic values showed no significant difference. This remained idem when the intraabdominal pressure (IAP) was gradually increased. In this study, we aimed to investigate the effect of (1) intermittent IAP elevations and (2) a low cardiac output (CO) on the blood pressure (BP) difference cranially (carotid artery) and caudally (femoral artery) of a capnoperitoneum (ΔP = P a fem-P a carot). Methods: A total of twenty-two piglets (mean body weight 11.0 kg; range 8.9-13.3 kg) were studied. Of these, 14 underwent intermittent IAP elevations at 8 and 16 mmHg, and ΔP was measured. In another 8 piglets, a model of reduced CO was created by introducing an air embolism (2 ml/kg over 30 s) in the inferior caval vein (VCI) at 12 mmHg IAP to further assess the influence of this variable on ΔP. Results: Systolic ΔP remained at a mean of 5.6 mmHg and was not significantly affected by insufflation or exsufflation up to an IAP of 16 mmHg. Diastolic and mean values showed no differences between P a carot and P a fem. P a fem, systol remained higher than its carotid counterpart as long as the cardiac index (CI) was above 1.5 l/min/m(2), but fell significantly below P a carot, systol at a low CI. There was no CO-dependent effect on diastolic and mean ΔP. Repeated IAP elevations do not significantly influence ΔP. Conclusions: Intermittent IAP elevations do not significantly influence ΔP. Despite of a CO-dependent inversion of systolic ΔP, mean BP measurements at the leg during laparoscopy remain representative even at low CO values.

Background: The aim of this study was to evaluate the risk of an air embolization with the volume of the insufflation tube during induction of laparoscopy. A further objective was to determine the LD₅₀ of air in young piglets. Methods: End-tidal carbon dioxide pressure ([Formula: see text]), pulmonary arterial pressure (P pa), heart rate (f c), and mean arterial pressure (P a carot) were measured in 17 piglets divided into three groups: group 1 (n = 6), bolus application (CO₂ embolization, followed by air embolization, 2 mL/kg each), group 2 (n = 7), continuous air embolization (30 min, 0.2 mL/kg/min), and group 3 (n = 4), continuous CO₂ embolization (30 min, 0.4 mL/kg/min). Results: All animals survived CO₂ embolism. Air embolization as a bolus (2 mL/kg) or with an accumulated volume of 3.1 mL/kg led to death. Decreases in [Formula: see text] indicated air or massive CO₂ embolization only. There was a good correlation between [Formula: see text] and P pa in case of air embolization (r = -0.80, p < 0.0001). In contrast, no dependency was recognized during CO₂ embolism (r = -0.17, p = 0.2). Conclusions: In order to minimize the lethal risk of gas embolization, the insufflation system has to be completely filled with CO₂ before connecting to the patient.

Background: Helium is used as an insufflation gas to avoid the negative properties of carbon dioxide (CO(2)), such as CO(2) accumulation, acidosis, and tachycardia, particularly in the case of insufficient respiratory function, seen also in infancy. Any laparoscopic procedure carries the risk of a gas embolism. Materials and methods: Seven anesthetized piglets (weighing 9.9-12.8 kg), randomized into three groups, served as models for pre-teenage children. Three piglets received a CO(2) embolism, followed by a helium embolism of 2 mL/kg, respectively. Helium was administered to three piglets, whereas both gases were repeatedly administered alternately to one piglet. The embolisms were administered for 30 seconds via a central venous line. Cardiac output was measured using the thermodilution method. The observation period for each embolism was 60 minutes in Groups 1 and 2 and 15 minutes in Group 3. Results: All animals survived CO(2) embolisms. Four of the six piglets died after helium embolisms. Following helium embolisms there was a prompt initial decrease in the end-tidal CO(2) pressure and an initial increase in the pulmonary arterial pressure. A further decrease in arterial blood pressure was prevented by a compensatory increase in the heart rate and appeared just before death. After only 5 minutes cardiac output showed a 25% decline from the initial value. Helium embolisms led to a severe increase in the pulmonary dead space. Conclusions: Embolisms with the smallest amounts of helium administered via direct venous puncture have an immediate lethal impact. Extended perioperative monitoring and trocar placement under vision should be performed.

The impact of a capnoperitoneum on the known blood pressure (BP) difference of the upper and lower limb was studied in piglets. Eleven German Landrace piglets (body weight, 4.3-7.4 kg; mean body weight, 6.2 kg) were studied. Arterial lines were placed in the right carotid and right femoral artery for pressure monitoring. Intraabdominal pressure levels were increased in steps of 6 mm Hg up to 24 mm Hg. We found that elevated intraabdominal pressures up to 24 mm Hg did not change the preexisting systolic BP difference between the carotid and femoral arteries. Systolic femoral artery pressure constantly remained 5% higher than its carotid counterpart. In addition, mean and diastolic values were not affected. Arterial BP measurements recorded at the legs of piglets when abdominal pressure is increased by up to 24 mm Hg can be used for intraoperative assessment of systemic arterial BP.

Einleitung: Vorhofseptumdefekte (PFO/ASD) werden mit einer Inzidenz von 9–30% angegeben. Einige Kleinkinder, die sich einem laparoskopischen Eingriff unterziehen, mussen diesem Patientenkollektiv zugerechnet werden. Ist ein RL-Shunt bei ASD wahrend bzw. nach Laparoskopie nachweisbar und welcher Einfluss besteht zur Oxygenierung? Methode: 18 Ferkel (8,85–13,25kg) wurden unter Beatmung (Normokapnie) 90 min Laparoskopiert (IAP bis 16mmHg). Bei 9 Tieren wurde zuvor ein ASD von 2–6mm erzeugt. Bestimmt wurden mittl. art. Blutdruck (MAP), mittl. rechter Vorhofsdruck (P RA mean), Wedge-Druck (PCWP), art. O2-Sattigung (SaO2) und Oxygenierungindex (Ox-Index) vor, wahrend und 20 Minuten nach Kapnoperitoneum. Ein RL-Shunt wurde sonographisch bestimmt. Ergebnisse: Bei 8 Tieren mit ASD war ein RL-Shunt darstellbar. Anderungen im Vergleich zum Ausgangswert vor Laparoskopie [Konfidenzintervall wahrend / nach Laparoskopie]: Kontrollgruppe: P RA mean [–1,1; 1,5mmHg]/[–0,5; 0,7mmHg], PCWP [–0,6; 1,6mmHg]/ [–0,5; 0,2mmHg], SaO2 [–2,8; 2,2%] / [–1,8; 3,1%], Ox-Index [0,5; 1,7] / [–0,5; 0,2], MAP [–16; 9%] / [–28; –6%]. ASD-Gruppe: P RA mean [–2,2; 1,7mmHg] / [–2,1; 0,35mmHg], PCWP [–1,2; 2,2mmHg] / [–1,4; 1,8mmHg], SaO2 [–12,8; –1,1%] / [–12,4; 1,7%], Ox-Index [–0,3; 3,0] / [–0,15; 0,9], MAP [–26; 5%] / [–33; –1%]. Der Druckgradient P RA mean – PCWP blieb in der Kontrollgruppe unverandert, in der ASD-Gruppe war auch bei neg. Wert ein RL-Shunt nachweisbar. Schlussfolgerung: Erniedrigte art. O2-Sattigung nach lap. Operationen konnen durch einen RL-Shunt auf der Basis eines Vorhofseptumdefektes bedingt sein. Dieser RL-Shunt tritt herzzyklusabhangig auf und kann nicht allein durch Vergleich des rechten Vorhofdruckes mit dem PCWP eingeschatzt werden.