H. U. Zieren
Humboldt University of Berlin
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Surgery | 1997
Christoph A. Jacobi; Robert Sabat; B. Böhm; H. U. Zieren; H.-D. Volk; J. M. Müller
BACKGROUND Port-site recurrences have often been reported after laparoscopic surgery for malignant disease, and the pathogenesis is unknown. Whether different gases used to establish pneumoperitoneum have an influence on tumor cell growth has not been investigated. METHODS Tumor growth of colon adenocarcinoma DHD/K12/TRb was measured in a rat model after insufflation with either carbon dioxide or helium and in a control group. Tumor growth was evaluated in three experiments: (1) in vitro (n = 60), (2) ex vivo (n = 60), and (3) in vivo (n = 60). After insufflation, cell kinetics were determined in the first two experiments. In the third experiment, tumor growth was measured subcutaneously and intraperitoneally 5 weeks after insufflation. RESULTS Tumor cell growth increased significantly after insufflation with carbon dioxide in vitro (p < 0.03) and ex vivo (p < 0.05) compared with the control group, whereas helium did not stimulate cell growth. In vivo, subcutaneous tumor growth was promoted by carbon dioxide (131 +/- 55 mg) (p < 0.01) compared with helium (35 +/- 34 mg) and the control group (36 +/- 33 mg). Total intraperitoneal tumor weight was 717 +/- 320 mg in carbon dioxide group compared with helium (549 +/- 231 mg) and control group (570 +/- 321 mg). CONCLUSIONS The insufflation of carbon dioxide promotes tumor growth compared with helium and control in a rat model. Further studies should confirm these results before alternative gases should be recommended in laparoscopic surgery for malignant diseases.
American Journal of Surgery | 1998
Jürgen Zieren; H. U. Zieren; Christoph A. Jacobi; F.A. Wenger; J. M. Müller
BACKGROUND Although tension-free techniques of hernia repair using synthetic meshes revealed encouraging results, the best method of inguinal hernia repair is still unclear. METHODS In a prospective randomized phase-II-B study, early postoperative results of laparoscopic transabdominal preperitoneal repair (n = 80), open plug and patch repair (n = 80), and Shouldices operation (n = 80) were compared. Postoperative pain and patients comfort were defined as main endpoints. RESULTS The laparoscopic approach had significantly longer operation time and was more expensive (61 +/- 12 minutes;
American Journal of Surgery | 1997
Christoph A. Jacobi; J. Ordemann; B. Böhm; H. U. Zieren; Robert Sabat; J. M. Müller
1,211) than plug and patch repair (36 +/- 14 minutes;
European Journal of Cardio-Thoracic Surgery | 1997
Christoph A. Jacobi; H. U. Zieren; J. M. Müller; H. Pichlmaier
124) and Shouldices operation (47 +/- 17 minutes;
Surgical Endoscopy and Other Interventional Techniques | 1997
C.A. Jacobi; J. Ordemann; B. Böhm; H. U. Zieren; C. Liebenthal; H.-D. Volk; J. M. Müller
69). Main postoperative complications were wound hematomas, seromas, and superficial wound infection, without significant difference between the groups. Postoperative pain, analgesia requirements, limitation of daily activities, and return to work did not differ between laparoscopic and open tension-free repair but were significantly lower in both groups compared with Shouldices operation. So far, no recurrence was observed after a mean follow-up of 25 months. CONCLUSION Open plug and patch repair is a promising technique of hernia repair in adults, because it offers the same excellent patient comfort as the laparoscopic repair but is less expensive and can be performed under local anesthesia.
Chirurg | 1999
F.A. Wenger; C.A. Jacobi; K. Haubold; H. U. Zieren; J. M. Müller
BACKGROUND The pathogenesis of portsite recurrences after laparoscopic surgery is still unknown, and a generally accepted approach to prevent tumor implantation does not exist. METHODS The effect of taurolidine and heparin on growth of colon adenocarcinoma DHD/K12/TRb was measured in vitro and in vivo. After incubation of the cells with heparin or taurolidine or both substances, cell kinetics were determined. In a rat model (n = 60), tumor cells were administered intraperitoneally, and pneumoperitoneum was established over 30 minutes. Rats received tumor cells, tumor cells + heparin, tumor cells + taurolidine, or tumor cells + taurolidine + heparin. RESULTS In vitro, tumor cell growth decreased after incubation with taurolidine and taurolidine/heparin. In vivo, intraperitoneal tumor weight was lower in rats receiving heparin (298 +/- 155 mg) and taurolidine (149 +/- 247 mg) compared with the control group (596 +/- 278 mg) but even less when both substances were combined (21.5 +/- 36 mg). CONCLUSION Heparin inhibits intraperitoneal tumor growth in vivo slightly, while taurolidine causes significant decrease of tumor cell growth in vitro as well as tumor take and intraperitoneal tumor growth in vivo.
Annals of Nutrition and Metabolism | 1999
F.A. Wenger; C.A. Jacobi; M. Kilian; Jürgen Zieren; H. U. Zieren; J. M. Müller
OBJECTIVE The effects of the different surgical approaches (transhiatal esophagectomy and right-sided transthoracic esophagectomy) on perioperative cardiopulmonary function in the surgical treatment of esophageal carcinoma are discussed controversially and have not yet been evaluated. METHODS In a prospective randomized study including 32 patients, we investigated the effects of the surgical approach (blunt dissection (n = 16) versus transthoracic en-bloc resection (EB) (n = 16)) in the treatment of esophagus carcinoma on perioperative cardiopulmonary function. The following parameters were measured in all patients: cardiac index (CI), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary artery pressure (MPAP), pulmonary capillary wedge pressure (PCWP), intrapulmonary shunt (QS/QT), arterio-alveolar (aaDO2), arterio-venous oxygen pressure difference (avDO2), and blood gas analyses. Time of measurement were: after induction of anesthesia, beginning and end of esophagus resection, end of surgery, 1 h postoperatively, and then every 12 h until the third postoperative day. RESULTS Compared to blunt dissection, en-bloc esophagectomy was found to be associated with a transient deterioration of pulmonary function during one-lung ventilation in the left-lateral position, which could already be compensated for during the intervention. No other significant differences in cardiopulmonary effects were seen between the two surgical techniques. The incidence of postoperative complications was identical in both groups. CONCLUSIONS The results of our study show that en-bloc resection is only associated with an increased intraoperative pulmonary strain that is completely compensated during the operation and that there is no difference in cardiopulmonary functions between the two techniques in the postoperative course.
European Surgical Research | 1996
Christoph A. Jacobi; H. U. Zieren; J. M. Müller; F. Adili; H. Pichlmaier
AbstractBackground: The effects of laparotomy and laparoscopy with different gases on subcutaneous and intraperitoneal tumor growth have not been evaluated yet. Methods: Tumor growth of colon adenocarcinoma DHD/K12/TRb was measured in rats after laparotomy, laparoscopy with CO2 or air, and in control group. Cell kinetics were determined after incubation with carbon dioxide or air in vitro and tumor growth was measured subcutaneously and intraperitoneally after surgery in vivo. Results: In vitro, tumor cell growth increased significantly after incubation with air and CO2. In vivo, intraperitoneal tumor weight was increased after laparotomy (1,203 ± 780 mg) and after laparoscopy with air (1,085 ± 891 mg) and with CO2 (718 ± 690 mg) compared to control group (521 ± 221 mg) (p < 0.05). Subcutaneous tumor growth was promoted after laparotomy (71 ± 35 mg) and even more after laparoscopy with air (82 ± 45 mg) and CO2 (99 ± 55 mg) compared to control group (36 ± 33 mg). Conclusions: Insufflation of air and CO2 promote tumor growth in vitro. In vivo, intraperitoneal tumor growth seems to be promoted primarily by intraperitoneal air and subcutaneous tumor growth by CO2.
Langenbeck's Archives of Surgery | 1999
Jürgen Zieren; Eric Castenholz; Christoph A. Jacobi; H. U. Zieren; J. M. Müller
BACKGROUND The Whipple operation (PD) is the standard operation in patients with cancer of the head of the pancreas and the periampullary region. However, the pylorus-preserving duodenopancreatectomy (PPPD) is supposed to be superior in gastrointestinal function. METHODS In a prospective randomized trial (October 1994-October 1998) PD and PPPD were compared in terms of global and gastrointestinal quality of life, operation time, duration of hospital stay, transfusions and perioperative morbidity. Quality of life was analyzed under standardized conditions (EORTC-QLQ-30) pre- and postoperatively (weeks 2, 6, 12, 24, 36, 48, and 60). RESULTS A duodenopancreatectomy was performed in 48 patients because of cancer of the head of the pancreas (n = 38) and the periampullary region (n = 10) (PD, n = 24; PPPD, n = 24). The PD and PPPD groups did not differ according to age, gender or UICC stage. Operation time was shorter in the PPPD group (206 +/- 48 vs 306 +/- 54 min) (P < 0.05). Morbidity did not differ between the two groups (PPPD 20% vs PD 30%, P > 0.05). While there was no difference in global quality of life, gastrointestinal quality of life was postoperatively increased in the PPPD group regarding appetite, nausea and diarrhea (P < 0.05). While the preoperative body weight was reached after 6 months in 85% of the PPPD group (n = 20), this was true in only 60% of the PD-group (n = 14) (P < 0.05). CONCLUSION PPPD seems to be associated with a better postoperative gastrointestinal quality of life than PD.Summary.Background: The Whipple operation (PD) is the standard operation in patients with cancer of the head of the pancreas and the periampullary region. However, the pylorus-preserving duodenopancreatectomy (PPPD) is supposed to be superior in gastrointestinal function. Methods: In a prospective randomized trial (October 1994–October 1998) PD and PPPD were compared in terms of global and gastrointestinal quality of life, operation time, duration of hospital stay, transfusions and perioperative morbidity. Quality of life was analyzed under standardized conditions (EORTC-QLQ-30) pre- and postoperatively (weeks 2, 6, 12, 24, 36, 48, and 60). Results: A duodenopancreatectomy was performed in 48 patients because of cancer of the head of the pancreas (n = 38) and the periampullary region (n = 10) (PD, n = 24; PPPD, n = 24). The PD and PPPD groups did not differ according to age, gender or UICC stage. Operation time was shorter in the PPPD group (206 ± 48 vs 306 ± 54 min) (P < 0.05). Morbidity did not differ between the two groups (PPPD 20 % vs PD 30 %, P > 0.05). While there was no difference in global quality of life, gastrointestinal quality of life was postoperatively increased in the PPPD group regarding appetite, nausea and diarrhea (P < 0.05). While the preoperative body weight was reached after 6 months in 85 % of the PPPD group (n = 20), this was true in only 60 % of the PD-group (n = 14) (P < 0.05). Conclusion: PPPD seems to be associated with a better postoperative gastrointestinal quality of life than PD.Zusammenfassung.Hintergrund: Die kephale Pancreaticoduodenektomie nach Kausch-Whipple (PD) gilt als Standardverfahren bei der chirurgischen Therapie des Carcinoms des Pankreaskopfes und der periampullären Region, jedoch soll die pyloruserhaltende Resektion (PPPD) hinsichtlich der gastrointestinalen Funktion Vorteile bieten. Methodik: In einer prospektiv-randomisierten Studie (10/94–10/98) wurden beide Operationsverfahren verglichen. Hauptzielkriterium waren die globale und gastrointestinale Lebensqualität (LQ), Nebenzielkriterien waren die Dauer der Operation und des stationären Aufenthaltes, sowie der Verbrauch von Blutkonserven und die perioperative Morbidität. Die Lebensqualität wurde standardisiert mit Hilfe des EORTC-QLQ-30-Bogens präoperativ und in der 2., 6., 12., 24., 36., 48. und 60. postoperativen Woche erhoben. Ergebnisse: Bei 48 Patienten erfolgte wegen eines Carcinoms des Pankreaskopfes (n = 38) und der periampullären Region (n = 10) eine Duodenopankreatektomie (PD n = 24, PPPD n = 24). Beide Gruppen unterschieden sich nicht hinsichtlich Alter, Geschlecht und Tumorstadium. Die Operationsdauer der PPPD-Gruppe war signifikant kürzer (206 ± 48 vs 306 ± 54 min) (p < 0,05), die Morbiditätsrate beider Operations-Gruppen unterschied sich nicht signifikant (PPPD 20 % vs PD-Gruppe 30 %). Während die globale LQ beider Patientengruppen nahezu identisch war, zeigten sich signifikante Vorteile für die PPPD-Gruppe hinsichtlich der gastrointestinalen Parameter Appetitlosigkeit, Übelkeit und Erbrechen sowie Diarrhoe. In der PD-Gruppe erreichten nur 14 Patienten (60 %) ihr präoperatives Körpergewicht nach 6 Monaten gegenüber 20 Patienten (85 %) der PPPD-Gruppe (p < 0,05). Schlußfolgerung: Diese Ergebnisse deuten auf eine Verbesserung der postoperativen gastrointestinalen Lebensqualität in der PPPD-Gruppe gegenüber der PD-Gruppe hin.
Chirurg | 2000
J. Zieren; H. U. Zieren; F.A. Wenger; J. M. Müller
Background: α-Linolenic acid (ALA) has been shown to have a promoting effect on pancreatic carcinogenesis. The purpose of this study was to evaluate the influence of ALA on liver metastases in a model of BOP-induced pancreatic ductular carcinoma in the Syrian golden hamster. Methods: While the control group (group V) received a standard diet low in fat (soya oil, 3 w/v) without ALA, groups I–IV were fed a diet high in fat (soya oil 25 w/v) with increasing percentages of ALA (2.5, 5, 7.5 and 10%) for 16 weeks. Results: No significant differences in mean body weight and pancreas weight were found between the groups. But significant differences (p = 0.0001) were observed in the mean weight of the resected liver. Treatment with BOP alone resulted in the induction of well-differentiated ductal pancreatic adenocarcinoma in 91%, while all groups treated with different amounts of ALA had induction of 100%. The incidence of liver metastases differed significantly between the groups. The incidence of liver metastases in group I (2.5% ALA) was 18%, in group II (5% ALA) 27%, in group III (7.5% ALA) 50%, and in group IV (10% ALA) 91%. Moreover, the diameter of liver metastases increased significantly according to ALA supplementation (p = 0.001). Conclusion: The results indicate that dietary ALA increases liver metastases in BOP-initiated pancreatic cancer.