Biomedical subjects

J J Bannenberg

Publications and source records attributed to J J Bannenberg.

14 recordsLinked to original sources

PubMed2000

Hand-assisted laparoscopic surgery: an overview.

BACKGROUND: Advanced laparoscopic surgery is complex and time-consuming. Achieving consistent efficacy and safety throughout the entire procedure is always a problem. For this reason, hand-assisted laparoscopic surgery (HALS) was developed. METHODS: Devices were designed to allow manual access to the abdomen through the utility laparotomy. By using one hand in the abdomen during laparoscopy, the surgeon regains direct tactile sensation and acquires improved hand-eye coordination. The safety of the individual devices has been tested in RCT for the registration of the individual devices. An index known as Surgical Action Efficiency was calculated for in six patients undergoing laparoscopic colon resection and six patients with hand-assisted colon resections. RESULTS: All of the registered devices are safe. Surgical Action Efficiency for the laparoscopy group was 55 +/- 14%; for the HALS group, it was 71 +/- 4%. This result is statistically significant (p < 0.05). CONCLUSION: HALS is a safe and efficient method by which it is possible to combine the established convenience and safety of open surgery with the advantages of minimally invasive surgery.

Hand↗

PubMed1999

Splenectomy revised: manually assisted splenectomy with the dexterity device--a feasibility study in 22 patients.

Laparoscopic splenectomy claims a number of advantages over open surgery: less trauma, quicker recovery, and faster return to normal activity. On the other hand, laparoscopic splenectomy is complex and time consuming, and so far, many surgeons are reluctant to perform such an operation. A new device was designed to give manual access to the abdomen through a utility laparotomy. By using one hand in the abdomen during laparoscopy, the surgeon regains direct tactile sense and hand-eye coordination. A pilot study to assess the feasibility of this method has been performed in 22 patients. The operation could be completed easily in 21 patients (95%). The average blood loss was 230 mL, and the average postoperative stay was 3.9 days. With this simple, inexpensive method, it is possible to combine the established convenience, safety, efficacy of open surgery with the advantages of minimally invasive surgery.

Adolescent↗

PubMed1998

Initial experiences with the retroperitoneal approach for endoscopic nephrectomy with the patient in the prone position.

Retroperitoneal endoscopic nephrectomy with the patient in the prone position was performed in 12 patients. Indications for this procedure were end-stage kidneys with ureteropelvic junction stenosis or distal ureteric obstruction, nonfunctional kidneys with drug resistant renin-mediated hypertension, and distal ureter malignancy. The retroperitoneal area was exposed using an open surgical technique in combination with the use of a liquid-filled dissection balloon. Removal of kidney tissue was performed with a morcellator through one of the ports. On average, the operating time was 210 min (range 160-480 min) to complete a one-sided nephrectomy. No major complications occurred. Mean hospital stay in this series was 6.6 days, and the follow-up period was uncomplicated in all cases. Retroperitoneal endoscopic nephrectomy with the patient in the prone position is an acceptable alternative to open nephrectomy in selected indications.

Adult↗

PubMed1997

Laparoscopic cholecystectomy using abdominal wall retraction. Hemodynamics and gas exchange, a comparison with conventional pneumoperitoneum.

BACKGROUND: Disadvantages related to CO2 pneumoperitoneum have led to development of the abdominal wall retractor (AWR), a device designed to facilitate laparoscopic surgery without conventional pneumoperitoneum (15 mmHg CO2). We investigated the effects of the AWR on hemodynamics and gas exchange in humans. We also investigated whether the use of an AWR imposed extra technical difficulties for the surgeon. A pilot study revealed that cholecystectomy without low-pressure pneumoperitoneum was technically impossible. METHODS: A prospective randomized controlled trial: Twenty patients undergoing laparoscopic cholecystectomy were randomly allocated into group 1: AWR with low-pressure pneumoperitoneum (5 mmHg), or group 2: conventional pneumoperitoneum (15 mmHg). RESULTS: Surgery using the AWR lasted longer, 72 +/- 16 min (mean +/- SD) vs 50 +/- 18 min compared with standard laparoscopic cholecystectomy. There were no differences between the groups with respect to hemodynamic parameters, although a small reduction of the cardiac output was observed using conventional pneumoperitoneum (from 3.9 +/- 0.7 to 3. 2 +/- 1.1 l/min) and an increase during AWR (from 4.2 +/- 0.9 to 5.2 +/- 1.5 l/min). Peak inspiratory pressures were significantly higher during conventional pneumoperitoneum compared to AWR. A slight decrease in pH accompanied by an increase in CO2 developed during pneumoperitoneum and during the use of the AWR. In both groups arterial PO2 decreased. CONCLUSIONS: The results indicate that the view was impaired during use of the AWR and therefore its use was difficult and time-consuming. Possible advantages of this devices' effects on hemodynamics and ventilatory parameters could not be confirmed in this study.

Abdominal Muscles↗

PubMed1997

Hemodynamics during laparoscopic extra- and intraperitoneal insufflation. An experimental study.

BACKGROUND: Total extraperitoneal laparoscopic surgery is an alternative to the laparoscopic transperitoneal route; however, its effects on hemodynamics have not been adequately studied. This experimental study compared the effects of intraperitoneal insufflation and extraperitoneal insufflation on hemodynamics and oxygen transport. METHODS: Sixteen pigs were randomly assigned for intraperitoneal insufflation or extraperitoneal insufflation with 15 mmHg carbon dioxide. Hemodynamic and oxygen transport parameters were taken during an hour of insufflation and analyzed for statistical differences. RESULTS: During extraperitoneal CO2 pneumoperitoneum central venous filling pressures (central venous pressure, pulmonary capillary wedge pressure and mean pulmonary arterial pressure) and end-tidal CO2 increased slower but to a similar magnitude in comparison to intraperitoneal insufflation. Cardiac output and indices of oxygen consumption and oxygen delivery were equally affected by both types of insufflation. Arterial CO2 pressure increased significantly more during intraperitoneal insufflation. CONCLUSION: The data from this study suggest that extraperitoneal insufflation might result in less cardiovascular impairment than intraperitoneal insufflation.

Analysis of Variance↗

PubMed1996

Laparoscopic-assisted colectomy with the dexterity pneumo sleeve.

UNLABELLED: The dexterity pneumo sleeve is designed to provide abdominal access for the surgeon's hand while preserving pneumoperitoneum during laparoscopy. The first experience using the dexterity pneumo sleeve in colorectal surgery is reported. METHODS: Four patients with diverticulitis and one with a dolichocolon had manually assisted laparoscopic sigmoid colectomy with the dexterity pneumo sleeve. RESULTS: Assistance of the left hand, introduced through the dexterity device proved to be extremely helpful in identifying the plane of dissection in one patient with a large diverticular mass and in another with a colovaginal fistula. Mean operative time was 109 minutes, blood loss was 80 ml, and length of incision was 7.5 cm. Flatus reoccurred at the second postoperative day, bowel movement occurred on the third day after surgery, and patients were discharged after 4.8 days. CONCLUSIONS: With the dexterity pneumo sleeve, the tactile sensation is regained, which makes laparoscopic-assisted colectomy safer and faster.

Blood Loss, Surgical↗

PubMed1995

Laparoscopy without pneumoperitoneum. Effects of abdominal wall retraction versus carbon dioxide insufflation on hemodynamics and gas exchange in pigs.

Laparoscopic surgery with CO2 insufflation is associated with adverse effects on hemodynamics and gas exchange. The abdominal wall retractor (AWR) is an alternative for pneumoperitoneum. Hemodynamics and gas exchange during the use of an AWR were compared to those of CO2 pneumoperitoneum. In eight pigs subjected to 1 h of CO2 pneumoperitoneum or abdominal wall retraction, hemodynamics, gas exchange, and oxygen transport were studied in a randomized cross-over study design. The only change observed during abdominal wall retraction was mild respiratory alkalosis. In contrast, during CO2 pneumoperitoneum mean arterial blood pressure increased 13%, central filling pressures doubled, and a small increase in cardiac output was observed. Peak airway pressures increased 50%, end-tidal CO2 increased 20%, and respiratory acidosis was induced (arterial pH from 7.46 +/- 0.07 to 7.31 +/- 0.06 and pCO2 from 33 +/- 3 mmHg to 53 +/- 4 mmHg). Arterial PO2 decreased but mixed venous oxygen saturation and oxygen consumption were unaffected. In contrast with CO2 pneumoperitoneum, laparoscopy using abdominal wall retraction was not associated with adverse effects on hemodynamics or gas exchange.

Abdominal Muscles↗

PubMed1995

Hemodynamics during laparoscopy in the supine or prone position. An experimental study.

During laparoscopy elevations in arterial pressure and a decrease in cardiac output have been reported. Laparoscopic surgery performed in the prone position may be advantageous for some surgical procedures, but the hemodynamic effects of pneumoperitoneum in this position have not been studied. We studied the effects of different levels of increased intraabdominal pressure on hemodynamics and oxygen transport in eight pigs in the prone and the supine position. Increases in intraabdominal pressure did not result in decreased cardiac output or in a reduction of oxygen transport and consumption in either position. These results suggest that laparoscopy in the prone position does not result in more severe hemodynamic depression than laparoscopy in the supine position.

Analysis of Variance↗

PubMed1995

Effects of pneumoperitoneum with helium on hemodynamics and oxygen transport: a comparison with carbon dioxide.

Pneumoperitoneum with CO2 is associated with adverse effects, such as hypercarbia, arrhythmias, and circulatory depression, which may limit its use in patients with underlying disease. Some of these effects may be caused by CO2 absorption resulting in acid-base disturbances. Laparoscopic insufflation with helium may be a good alternative for CO2, since it is chemically inert. Because there are few data on the use of helium for laparoscopy, we studied hemodynamics and gas exchange during insufflation with CO2 or helium in 8 pigs at 10, 15, and 20 mm Hg intraabdominal pressure. Heart rate did not change significantly with both gases. Arterial blood pressure increased with CO2 (p < 0.05) but not with helium. Cardiac output, mixed venous oxygen saturation, and oxygen consumption did not decrease, whereas central venous filling pressures increased during insufflation with either gas. Insufflation with CO2 resulted in mild increases in arterial, central venous, and end-expiratory CO2. The results suggest that pneumoperitoneum with helium will not be associated with profound circulatory depression or oxygen transport abnormalities. In addition, the use of helium is not associated with acid-base disturbances, although central venous filling pressures are similarly increased as with the use of CO2 pneumoperitoneum.

Acid-Base Imbalance↗

PubMed1995

Extraperitoneal laparoscopic paraaortic lymph node sampling in prone position: development of a technique.

Paraaortic lymph node sampling has been found to be efficient in the staging of genitourinary cancers. However, the complications associated with this procedure using the traditional transperitoneal or extraperitoneal approach are considerable. Developments in endoscopic technology and instrumentation have allowed an extraperitoneal approach. Presented is a porcine model for extraperitoneal endoscopic paraaortic lymph node dissection as a staging procedure for genitourinary cancers. The pig is placed in a prone position, and an extraperitoneal pneumoperitoneum is created. Using a three-port technique, we were able to remove almost 95% of all paraaortic lymph nodes laparoscopically without any complications. The prone position allows for a fast and safe procedure because it minimizes the need for extra entry ports and gives a clear view, unobstructed by the bowel, of the back wall of the abdomen.

Animals↗

PubMed1995

Retroperitoneal endoscopic lumbar sympathectomy: laboratory and clinical experience.

Retroperitoneal endoscopic lumbar sympathectomy was performed in four pigs in the prone or lateral position to study the feasibility of these new approaches. Positioning, port placement and the dissection technique are described in detail. In nine patients retroperitoneal endoscopic lumbar sympathectomy, using the lateral position technique, was performed. The importance of port placement and dissection techniques for visualisation of the sympathetic chain are emphasised. The endoscopic retroperitoneal approach enables the sympathetic chain to be accurately localised whilst enhanced endoscopic vision aids dissection. Retroperitoneal endoscopic lumbar sympathectomy is a feasible technique offering patients the benefits of the minimally invasive approach.

Animals↗

PubMed1995

Experimental retroperitoneal endoscopic surgery.

Techniques for retroperitoneal endoscopic procedures with the patient in prone position were evaluated in experimental studies in the pig. Nephrectomy, para-aortic lymph node dissection, lumbar sympathectomy and assisted aorto-femoral bypass were performed and the experience is reported herein. The prone position contributes to the creation of the retroperitoneal working space and eliminates the need for extensive retraction and thus for additional ports. The modified open Hasson technique was found to be the preferred retroperitoneal access procedure.

Animals↗

PubMed1994

The prone position. Using gravity for a clear view.

Obtaining a clear view during laparoscopic surgery in the posterior abdominal cavity, on the abdominal backwall, or during colon surgery is time consuming and therefore one of the major objections to these procedures. In an experimental setting we positioned the animals in the prone position using the abdominal flanks to introduce the trocars. Our experience with this position is that a clear and unobstructed view of the abdominal back wall and the large intestines is obtained, facilitating laparoscopic procedures in these areas.

Abdomen↗

PubMedDate not supplied

Experimental videothoracoscopic cannulation of the left atrial appendix. A feasible rapid approach for initiating left heart bypass?

Rapid implementation of left ventricular assistance without thoracotomy for temporary support of patients with severe, life-threatening, acute cardiac power failure potentially expands applications of such support devices. A thoracoscopic technique for direct cannulation of the left atrium is described. In healthy closed-chest pigs, it proved a feasible method for effective volume unloading of the left ventricle.

Animals↗