Search PubMed⌕ Search

Biomedical subjects

K Peitgen

Publications and source records attributed to K Peitgen.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Extended resection of locally advanced primary and recurrent rectal carcinomas by interdisciplinary cooperation of various surgical specialties].

Multivisceral resections have been performed on 35 patients with primary and 45 with recurrent rectal cancer. Lethality was 3.7%, morbidity was 9%. Macroscopic adhesions were confirmed histologically as tumorous in 66% of the additionally resected organs. Tumor invasion, tumor recurrence and surgical radicality were found as statistically significant prognostic factors. In radically resected primary tumors 5-yr-survival was 49%. Multivisceral resection in rectal cancer is possible with low morbidity and lethality and potentially curative in primary tumors. In recurrent tumors multivisceral resections are frequently palliative.

Abdominal Neoplasms↗
PubMed1998

[Subtotal retroperitoneoscopic adrenal gland resection--an alternative to adrenalectomy?].

Primary adrenal tumors were removed in 24 patients by the posterior retroperitoneoscopic approach, maintaining tumor-free parts of the ipsilateral adrenal gland. These partial adrenal resections did not cause a significantly different operating time or blood loss compared to 58 complete adrenalectomies performed during the same period. All 20 patients with hormonally active tumors are biochemically and clinically cured (mean follow-up 18 months). In selected cases the retroperitoneoscopic subtotal adrenal gland resection is a safe procedure, which can potentially maintain the function of the adrenal gland's cortex.

Adrenal Gland Neoplasms↗
PubMed1997

[Translaryngeal tracheostomy. Technique and initial results].

Translaryngeal tracheostomy is a new type of minimally invasive technique for bedside tracheostomy in intensive care patients. After percutaneous puncture of the trachea below the first tracheal ring, a conic tracheal cannula is fixed to an orally forwarded guide wire. The cannula is then pulled through in orthograde fashion set up, rotated and pushed forward caudally. Among the first 25 translaryngeal tracheostomies in 24 patients, only two complications appeared: one misplacement of the cannula and one infection of the stoma. During a median apnoea time of about 80 s an average PaCO2 increase of 8.0 +/- 6.8 mm Hg was documented; hypoxias could not be seen. Translaryngeal tracheostomy seems to be an appropriate alternative to established tracheostomy methods.

Aged↗
PubMed1997

[Open approach or Veress needle in laparoscopic interventions? Results of a prospective randomized controlled study].

In a prospective randomized study on 50 patients undergoing laparoscopic surgery, the safety and feasibility of open access laparoscopy was analyzed and compared to the closed Veress needle technique. Open access laparoscopic surgery was performed in half the time needed for the Veress needle technique with equal safety and without complications or technical disadvantages. Furthermore, open access offers economical advantages, as disposable trocars are no longer needed. Therefore the open access technique is recommended as the standard for laparoscopic operations.

Adult↗
PubMed1997

First results of laparoscopic gastrostomy.

BACKGROUND: Laparoscopic gastrostomy as an alternative to open gastrostomy was introduced with various technical variants 5 years ago. However, long-term results of these new methods are still lacking. METHODS: From 4/1993 to 2/1996, laparoscopic gastrostomies were performed on 42 patients (50.9 +/- 15.6 [24-71] years) with esophageal stenosis in locally advanced hypopharyngeal (17 patients) or oropharyngeal (nine patients) carcinoma, incurable esophageal carcinoma (13 patients) and cerebral dyspagia (three patients). Operating time was 38 +/- 11 min [15-65 min]. Procedure-related mortality was 0%. Major complications occurred in 2/42 (4.7%) patients; minor complications were found in 4/42 (9.4%) patients. During a total usage time of 427 months, 14 stoma infections occurred (0.11 infections/100 days). CONCLUSION: Laparoscopic gastrostomy allows a safe, fast, and cheap reestablishment of enteral nutrition. The procedure is minimally invasive and can also be performed under local anesthesia. It has become our method of choice in patients with malignant, nonresectable subtotal stenosis of the hypopharynx or esophagus.

Adult↗
PubMed1997

Impact of particulate contamination in crystalloid cardioplegic solutions: studies by scanning and transmission electron microscopy.

The amount of particulate matter present in Bretschneider's cardioplegic solution (HTK) was assessed by laser-mediated particle counting. Permissible levels of contaminant particles with a distribution of diameters between 0.2 and 20 microns were found. A significant further increase in the particle count was observed when the fluid was administered for clinical use, which resulted in the additional release of particles from, for example, the infusion kit, which included an in-line filter with pores of 270 microns. Filtration of the HTK solution by a terminal inline filter (0.2 micron) significantly reduced the number of particles. In order to determine the chemical composition and the potential hazards of the particulate material we used scanning electron microscopy in combination with energy dispersive X-ray analysis and transmission electron microscopy to examine specimens taken from heart tissue obtained from Göttinger minipigs after cardioplegia and from humans undergoing mitral valve replacement after cardioplegia and reperfusion. Particles of various diameters were found either to be plugging coronary capillaries, to be adherent to the endothelial layer, or to be engulfed by polymorphonuclear (PMN) granulocytes, which appeared to be activated. Some of the PMN granulocytes were apparent in the endothelial layer. It is recommended, therefore, that a terminal in-line filter (0.2 micron) should be routinely used.

Animals↗
PubMed1997

[Experiences with a vent button system in endoscopic and surgical gastrostomy].

INTRODUCTION: In all variants of surgical or endoscopic gastrostomies, the abdominal wall is penetrated by a catheter. This reduces life-quality and often induces complications in gastrostomies. METHOD: In a prospective trial, an anti-refluxive replacement button was applied as a catheter-substitute in 45 patients after conventional, laparoscopic and percutaneous-endoscopic gastrostomies. RESULTS: In 1 of 45 patients the button was falsely inserted, only two patients experienced minor local infections of the stoma. No further major complications were noted. The average usage-time is 6.3 +/- 4.9 [1-17] months, the rate of complications in 100 days is 0.06. CONCLUSIONS: The gastrostomy replacement button is safely applicable and improves clearly the comfort of gastrostomies with a low complication rate.

Adolescent↗
PubMed1997

[Surgery of primary unilateral adrenal gland tumors--results of 154 patients].

Surgical resection of adrenal neoplasias with endocrine activity is principally indicated. In adrenal neoplasias without endocrine activity, surgical removal is indicated in relation to tumor size. Surgical access and extent of resection are the major problems related to adrenal surgery. From 1980 to 1996, in 154 patients (62 m, 92 f) primary and unilateral adrenal tumors (139 benign, 15 malign) were resected. 93 resections were performed transperitoneally, 13 extraperitoneally, and 48 retroperitoneoscopically. Subtotal adrenal resections were performed in 23 benign tumors smaller than 4 cm. Perioperative lethality was 0%, morbidity was 31.8%. Malignancy was correlated to tumor size: In 114 tumors smaller than 5 cm, no malign neoplasia was found, whereas in 40 tumors larger than 5 cm, 15 specimen were malign. Operating time of the retroperitoneoscopic method was significantly longer than of open procedures (p < 0.05). Postoperative analgotic medication was significantly reduced after endoscopic surgery compared to transperitoneal or extraperitoneal surgery (p < 0.0001). No tumor recurrences occurred after subtotal adrenal resections (mean follow up: 5.7 [1.3 years]). In patients with adrenal carcinomas, 5-year-survival was approximately 15%. In adrenal neoplasias smaller than 5 cm, malignancy is extremely rare. Therefore, less aggressive surgery with a lower morbidity (extraperitoneal approach) and reduced postoperative pain (retroperitoneoscopic approach) including function preserving resection is indicated in these lesions. Due to the high incidence of malignancy, adrenal tumors larger than 5 cm should principally be treated by conventional transperitoneal surgery.

Adolescent↗
PubMed1997

[Bile duct lesions in laparoscopic cholecystectomy--methods of reconstruction and results].

From 1/1991 to 1/1997 a total of 18 patients with major biliary lesions after laparoscopic cholecystectomy were treated. Besides 4 biliary strictures (Bismuth III, Siewert II), which were found between 20 and 180 days after laparoscopic cholecystectomy, large defects (Siewert III, IV) of the proximal parts of the hepatic duct (Bismuth III, IV) occurred in the majority of cases (n = 14). Except for 3 intraoperatively realized lesions, diagnosis was made during the first 3 weeks. Subsequent reinterventions resulted in a high morbidity rate and the need of further procedures to establish definitive biliary reconstruction. Selection criteria of the technique used for repair were the extension of the biliary lesion and the exposure of the distal stump of the common bile duct. A small defect was treated by direct suturing protected by a t-tube (n = 1). Large defects and biliary strictures were reconstructed using either a Roux-en-Y bilio-digestive anastomosis (n = 7) or jejunal interposition (n = 10). The results suggest, that early repair of biliary lesions after laparoscopic cholecystectomy should be achieved. Besides the standard procedure of bilio-digestive anastomosis, reconstruction of major biliary lesions should be performed by jejunal interposition in selected cases.

Adolescent↗
PubMed1997

[Laparoscopic gastrostomy--advantages in comparison with percutaneous endoscopic gastrostomy (PEG)].

Laparoscopic gastrostomy was performed on 70 patients with contraindications to PEG. All procedures were performed successfully, even in patients with gastric resections, after gallbladder surgery, and in patients with liver cirrhosis and ascites. Long-term results comprise a low complication rate of 0.12 in 100 application days. Laparoscopic gastrostomy is a highly effective procedure with low morbidity and good long-term results in patients with contraindications to PEG requiring enteral feeding.

Adult↗
PubMed1996

[Leiomyosarcoma of the stomach--clinical aspects, morphology and therapy].

BACKGROUND: Due to the rarity of gastric leiomyosarcomas, only little is known on the results of diagnostics and therapy of these tumors. According to literature, the problem of suitable criteria in determining malignancy of these neoplasms is unsettled. PATIENTS AND METHOD: 21 patients (10 male, 11 female; aged 13 to 74 [53 +/- 13,9] years) with leiomyosarcomas of the stomach were treated from 1978 to 1993. In a retrospective study, the diagnostic and therapeutic results and the pathologic features of these patients are compared with the results of literature. RESULTS: Diagnosis was rarely confined preoperatively. Potentially curative resection was possible in 13/21 cases. Five year survival was 44% overall (R0-resections: 60%, R1/2-resections 22%) with a wide spread of individual cases. Pathologic examination of the tumors showed only half of the tumors classifiable according to the system of McGrath. Some well differentiated tumors revealed unclear malignancy criteria. Analysis of prognostic factors showed no statistically significant influence of surgical radicality but a significant influence of tumor size, mitotic activity and nuclear grading on survival and recurrence. CONCLUSIONS: Because of their rare incidence, the treatment of gastric leiomyosarcomas remains non-standardized. Surgical radical removal of the tumor seems to promise the largest benefit. The treatment of patients with residual or recurrent tumors remains individual, no adjuvant radio- or chemotherapeutical treatment can be generally recommended.

Adolescent↗
PubMed1996

Posterior retroperitoneoscopy as a new minimally invasive approach for adrenalectomy: results of 30 adrenalectomies in 27 patients.

Posterior retroperitoneoscopic adrenalectomy is a new minimally invasive method. It represents an alternative to conventional open procedures and laparoscopic techniques. Between July 1994 and November 1995 a total of 30 retroperitoneoscopic adrenalectomies were performed on 27 patients. In 24 patients, unilateral tumors were seen (size 1-7 cm): seven Cushing adenomas, five Conn adenomas, seven pheochromocytomas, four hormonally inactive tumors, one cyst. Three patients suffered from Cushing syndrome with bilateral adrenal gland hyperplasias (two inoperable pituitary gland tumors, one bronchial carcinoid with ACTH secretion). The operations were carried out in prone position. After balloon dilatation of the retroperitoneum and creation of a pneumoperitoneum the preparation of the adrenal gland was performed via three trocar sites positioned below the 12th rib. Twenty-five adrenalectomies were completed endoscopically, and five times (among four patients) conversion to the conventional posterior technique was necessary. The average operating time of complete endoscopic adrenalectomies was 124 minutes (45-225 minutes); blood loss was 10 to 120 ml. With minimal need for postoperative analgesia (average dosage 7.9 mg of piritramide), mobilization and adequate food uptake were possible on the day of operation. The posterior retroperitoneoscopic adrenalectomy is a relatively fast, safe method, with the advantages of the posterior open approach and minimally invasive surgery. It therefore represents an important addition to adrenal gland surgery.

Adenoma↗
PubMed1996

A prospective randomized experimental evaluation of three-dimensional imaging in laparoscopy.

BACKGROUND: Restricted depth perception in laparoscopy with two-dimensional imaging has been reported to be a major disadvantage of minimally invasive procedures. Three-dimensional imaging units have been available for almost 2 years and are slowly being integrated into endoscopic surgery. So far, potential advantages or disadvantages have not yet been studied prospectively. METHODS: We evaluated the effects of three-dimensional imaging on surgical performance and its influence on surgeons at different experience levels in a prospective randomized trial. Twenty participants without laparoscopic experience (novices), 20 with less than 50 laparoscopic procedures (beginners), and 20 with more than 50 laparoscopic procedures (advanced surgeons) took part in two different tests (tube test and loop test) on a pelvitrainer. In random order, each test was conducted using a three-dimensional imaging unit under two-dimensional and three-dimensional conditions. During each test, the time was measured and the mistakes counted. The difference of time and number of mistakes for two-dimensional and three-dimensional conditions were calculated for each participant. RESULTS: Speed (p < 0.0001) and accuracy (p < 0.0001) were significantly better under three-dimensional conditions irrespective of the randomized sequence of each individual test. Speed was also influenced by individual experience (p > 0.02). Performance time decreased by 24.4% +/- 2.8% (m +/- SD), and the number of mistakes decreased by 52.5% +/- 27.9% (m +/- SD), as compared with the two-dimensional mode, with no significant influence of individual experience. CONCLUSIONS: Three-dimensional imaging significantly improves performance (speed and accuracy) regardless of previous laparoscopic experience. Thus, three-dimensional imaging may further improve the safety aspect of minimally invasive surgery.

Analysis of Variance↗
PubMed1996

Hemodynamic changes after retroperitoneal CO2 insufflation for posterior retroperitoneoscopic adrenalectomy.

Intraoperative complications and hemodynamic alterations during posterior capnoretroperitoneoscopic adrenalectomy in the prone position were investigated in 16 consecutive patients using invasive hemodynamic monitoring. Under general anesthesia with propofol and fentanyl, hemodynamic changes were made before (M1) and during retroperitoneal CO2 insufflation (15 mm Hg) [M2]; 20 mm Hg [M3]. Retroperitoneal insufflation resulted in a significant increase of cardiac output (+72%), stroke volume (+42%), mean arterial pressure (+39 %), and mean pulmonary arterial pressure (+36%). Although retroperitoneal inflation was accompanied by a significant increase of central venous pressure (+37%), an increase of preload may have lead to higher filling pressures. Heart rate, systemic vascular resistance, and pulmonary vascular resistance did not show significant changes. One pneumothorax and two cutaneous emphysemas occurred. We have demonstrated, in a small number of patients, that retroperitoneal CO2 insufflation for posterior capnoretroperitoneoscopic adrenalectomy in the prone position results in hemodynamic changes without apparent adverse effects.

Adolescent↗
PubMed1995

[Results of surgical treatment of local and locoregional recurrence of rectal carcinoma--an analysis of 54 patients].

The role of secondary resections of locally and locoregionally recurrent rectal cancer is still unclear concerning local tumor control and survival. A retrospective study of 54 patients undergoing resections of recurrent rectal cancer from 1984 to 1992 was done to define the role of secondary surgery and additive or adjuvant therapies. Extended resections of adjacent organs were performed in 37 patients. Potentially curative surgery was possible in only 7/54 patients, in 14 patients microscopically residual tumor (8 of these patients receiving intraoperative radiation therapy [IORT], and in 33 patients (11 of these cases with distant metastases) macroscopic tumor had to be left. A preoperative or postoperative radiation therapy partly in combination with IORT, hyperthermia or chemotherapy was applied in 26 patients. Median survival was 12.5 months in all patients, 19 months in patients without distant metastases and 8 months in patients with distant metastases, respectively. Radical surgery and localisation of the recurrent tumors were the main prognostic factors: Median survival of patients without distant metastases (n = 43) was 17 months in patients with pelvic wall recurrence, 33 months in patients with anastomotic or perineal recurrence and 39, 20 and 16 months in R0-, R1 and R2-resected patients, respectively. Local tumor control was achieved in only 10 of all patients, but in 4 of 8 patients receiving IORT. In total, only 5 of 54 patients are cured potentially. In conclusion, resection of recurrent rectal cancer, even in combination with additive or adjuvant therapies, only rarely leads to local tumor control and final cure.

Adult↗
PubMed1995

[Dorsal retroperitoneoscopic adrenalectomy--a new surgical technique].

For the first time the surgical technique of right and left adrenalectomy by a posterior percutaneous retroperitoneoscopic access is described. The adrenal gland is mobilized after creation of a pneumoretroperitoneum and insertion of 3-4 trocars beneath the 12th rip. Indications for this new method are small, benign adrenal tumours or adrenocortical hyperplasias. By this method, the potential advantages of a posterior approach and minimally-invasive surgery are combined. This surgical technique might become a major advancement in adrenal surgery.

Adrenal Cortex↗