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At least 19 recordsLinked to original sources
PubMed2001

[Spiral trocar--a new trocar concept].

INTRODUCTION: We would like to introduce a new trocar technique for minimal invasive surgery. The new trocar is a spiral whose coil becomes ever increasingly stronger towards the centre. Because of this, there is a smooth transition between spiral, screw and rod. The outer diameter remains the same. The spiral-trocar is screwed through the abdominal wall like a corkscrew. Because of this, the primary channel of puncture runs spirally. Furthermore, the channel is dilated and centralised so that the trocar's rod together with its sleeve can be pushed through the abdominal wall. This trocar design demonstrates the following advantages: The trocar can be screwed through the abdominal wall in a controlled manner without having to apply axial pressure. This prevents any unintentional perforation of organs. Because different layers of the tissue are penetrated at different places, they overlap, thus sealing one another after removal of the sleeve. The puncture channel was minimal, thus leaving very little risk of trocar site hernia. METHODS: The spiral-trocar was examined and compared with other types of trocars in vivo and vitro. RESULTS: During these tests, the spiral-trocar demonstrated a high level of safety and good usability. DISCUSSION: The spiral-trocar is an easily cleanable, reusable product without a mechanical sealing device and can be used together with most sleeves. This makes it very cost effective.

Animals↗
PubMed2000

Efficacy of establishment of pneumoperitoneum with the Veress needle, Hasson trocar, and modified blunt trocar (TrocDoc): a randomized study.

PURPOSE: To compare three techniques of establishment of pneumoperitoneum for efficacy: the Veress needle/first trocar, the Hasson trocar, and a newly developed modified blunt trocar, the TrocDoc. PATIENTS AND METHODS: Between June and December 1999, 62 patients eligible for laparoscopic surgery were randomized. The effectiveness of installation of the pneumoperitoneum using the three techniques was assessed by time-motion analysis. Primary efficacy measures were total time and number of actions required to establish the pneumoperitoneum. Secondary efficacy measures were procedure-related complications, wound complications, and occurrence of CO2 leakage. RESULTS: Two patients were withdrawn from inclusion. The three groups were comparable for age and body mass index. Total time was shortest using the TrocDoc rather than the Veress needle/first trocar and the Hasson trocar (respectively, 138 +/- 58 v 237 +/- 56 v 350 +/- 103 seconds), and the number of actions was lowest for the Veress needle/first trocar combination: 22 +/- 7 v 32 +/- 12 (TrocDoc) v 53 +/- 17 (Hasson). There was no morbidity related to the installation of pneumoperitoneum nor trocar wound complications. Gas leakage occurred in five of the Hasson introductions. CONCLUSIONS: Establishment of the pneumoperitoneum is more efficient using the TrocDoc compared with the Veress needle/first trocar and the Hasson trocar. The TrocDoc might replace the two alternatives because of its efficacy and open method of introduction.

Equipment Design↗
PubMed1999

Comparison of wounds created by non-bladed trocars and pyramidal tip trocars in the pig.

Wounds made by the Endopath nonbladed obturator, the Step trocar, and conventional pyramidal tip trocars were compared. The endopath nonbladed obturator and the Step trocar made wounds by separating tissue fibers, whereas the pyramidal tip trocar cut tissue fibers. The wounds of the Endopath nonbladed obturator and the Step trocar were similar in length but were narrower than wounds made by the pyramidal tip trocar. Further studies are needed to determine whether the wounds made by the Endopath nonbladed obturator and the Step trocar will have fewer complications than conventional pyramidal tip trocars.

Abdominal Muscles↗
PubMed2000

The driving force in trocar insertion: a comparison between disposable and reusable trocars.

BACKGROUND: Insertion of the first trocar during the "closed" technique of creating a pneumoperitoneum remains one of the most hazardous maneuvres in laparoscopic surgery, with complications such as major vascular and bowel injuries. The ease with which trocars are inserted through the abdominal wall may have some bearing on these complications. METHODS: A range of both disposable and reusable trocars, which were identical in point cross section and size, were compared in an abdominal wall model reconstructed with animal hide, using a hand-held pressure transducer. Multiple insertions were performed, and the results were expressed in pounds per square inch (PSI). RESULTS: The disposable trocar tested required the least effort to insert (mean pressure, 2.76 PSI), followed by the new reusable (mean pressure, 3.42 PSI), with the used reusable trocar requiring the greatest force for insertion (mean pressure, 4.80 PSI). CONCLUSIONS: The effect of previous use on ease of insertion demonstrates an obvious disadvantage of reusable instruments. The excessive force required to insert some trocars may place the patient at greater risk of trocar injury.

Abdominal Muscles↗
PubMed1997

Combination of subcutaneous abdominal wall retraction and optical trocar to minimize pneumoperitoneum-related effects and needle and trocar injuries in laparoscopic surgery.

BACKGROUND: Both pneumoperitoneum and blind needle and trocar insertion may cause complications: because of the well-known physiological effects, CO2 insufflation is not indicated in patients with impairment of cardiorespiratory function and high-risk patients; injuries to underlying viscera and vessels by needles and trocars have been reported even when the open technique is used. METHODS: A technique which combines abdominal wall suspension by a new subcutaneous lifter (LaparoTenser) and optical trocar (OptiView) insertion has been evaluated in a random series of 22 patients undergoing various laparoscopic procedures. The optic trocar was inserted without previous insufflation, but low-pressure (1-5 mmHg) pneumoperitoneum was associated during the course of the procedure in 16 cases. RESULTS: The exposure of the operating field was good or sufficient in 21 cases (95%), while the placement of the optical trocar was always safe. One complication related to the insertion of the subcutaneous needles of the wall lifter occurred (suprafascial hematoma). CONCLUSIONS: The subcutaneous retractor allows the use of conventional cannulae and the combination of abdominal wall suspension with or without low-pressure pneumoperitoneum, thus enhancing the quality of exposure with no effect on the hemodynamic and respiratory functions.

Abdominal Muscles↗
PubMed1994

Incarcerated trocar-wound hernia after laparoscopic hysterectomy. Is closure of large trocar fascia defects after laparoscopy necessary?

An incarcerated hernia through a 12-mm laparoscopic trocar wound, causing small bowel subobstruction, was diagnosed in a 50-year-old female patient following a laparoscopic hysterectomy 1 month earlier. Trocar-wound hernias causing early postoperative bowel obstruction are very rare. Insertion of trocars at a narrow angle to the abdominal wall may cause larger fascia defects than the actual size of the trocar. Manual examination and closure of large defects, if possible, may prevent such complications.

Fascia↗
PubMed1996

Abdominal wall stability: a comparison of the optical trocar with a reusable laparoscopic trocar.

The principal reason for employing an optical trocar has been described by Kaali.' The potential clinical benefits of a visually directed trocar entry system have been identified in a follow-up clinical series. 2 Current experience with the commercially developed Endopath Opt.iview" trocar has suggested an ad- ditional surgical advantage through an enhanced abdominal wall stability of the trocar sheath. The purpose of the current investigation was to determine whether or not this clinical observation could be mechanically quantified.

Journal Article↗
PubMed2006

A randomized, prospective study comparing the use of the missile trocar and the pyramidal trocar for laparoscopy access.

BACKGROUND: The missile trocar was developed for smooth abdominal penetration of the primary port. It contains a longitudinal tunnel connecting the abdominal cavity with the outside. OBJECTIVE: To evaluate the efficacy of the missile trocar compared with the traditional method using the Veress needle. MATERIAL AND METHOD: The times required to enter the abdominal cavity and the difficulty of the procedure were compared with the traditional Veress needle. A blind technique was used on 100 consecutive patients in a randomized fashion. RESULTS: The missile trocar technique took 2.7 +/- 1.6 minutes to perform compared with 3.9 +/- 1.3 min in the Veress needle group (p = 0.001), and the difficulty of the procedure was 2.1 +/- 1.9 cm (p = 0.433) rated from 10-cm scale. No carbon dioxide leakage or serious complications occurred in any patient. CONCLUSION: The results of the present study indicate that a long-tip missile trocar technique may be used safely when the technique is fully understood. This procedure is a relatively quick alternative approach for laparoscopy.

Abdomen↗
PubMed2001

Blunt hasson trocar injury: long intra-abdominal trocar and lean patient--a dangerous combination.

Injury at the time of trocar placement with the Hasson approach is rare. The cone of the Hasson cannula is wedged into the skin for an air seal, and, using fascial sutures, fastened under tension to flanges of the cannula. The shorter the fascial securing suture, the greater the tension and the more secure the air seal. Flanges for securing the fascial suture were attached to the external cannula in early Hasson cannula models. With these, much of the trocar needs to be intra-abdominal in order to shorten the suture. For lean patients, with very little distance between the anterior and posterior abdominal walls, the force required to fasten the sutures to the flanges may allow an intra-abdominal trocar to damage intervening organs. Later versions of the cannula had the flanges attached to the cone, allowing for short suture without need for intra-abdominal cannula. These models avoid the possibility of such injury. An unusually lean patient underwent laparoscopic cholecystectomy using an older Hasson cannula with flanges for the fascial securing suture attached to the cannula. Postoperative changes in vital signs and hemoglobin led to a diagnosis of intra-abdominal bleeding, and laparotomy revealed a transsected branch of the middle colic artery. Earlier Hasson cannulas, where the flanges are attached to the cannula, should be replaced with those with flanges attached to the cone.

Adult↗
PubMed1996

Visually guided trocar entry: experience with the optical trocar.

Blind insertion of the Veressneedle and the conventional primary trocar have remained troublesome steps during laparoscopic surgical procedures. The standard primary trocar can be inserted directly without preexisting pneumoperitoneum, thus avoiding use of the Veressneedle. This approach still requires blind insertion, and inadvertent traumatic injuries have been reported.' Complications from such trocar insertions can be severe and at times lethal. Although the rate of such complications is acknowledged to be small, the ab- solute number becomes a relevant public health issue in light ofthe high frequency of both operative and di- agnostic laparoscopic procedures worldwide. Traumatic injuries to vessels, bowel, and other abdominal or- gans continue to occur despite proper surgical training, operator experience, and use of up-to-date equipment.

Journal Article↗
PubMed1995

Access techniques: Veress needle--initial blind trocar insertion versus open laparoscopy with the Hasson trocar.

The two most common techniques used to gain entry into the peritoneal cavity during laparoscopic general surgery are the blind Veress needle/trocar insertion and open trocar placement under direct visualisation. Once entry to the peritoneal cavity has been achieved, gas insufflation is used to establish pneumoperitoneum and enable visualisation of abdominal structures. Many of the complications associated with operative laparoscopy arise from creation of the pneumoperitoneum, such as subcutaneous emphysema and gas embolism, or from injury to internal structures during abdominal entry. Because of the relative infancy of laparoscopic general surgery, much of the information relating to these types of complications are associated with minimally invasive gynaecologic procedures. Compared to gynaecologic laparoscopy, general surgical interventions are typically more complicated, require longer operative times and a greater number of access sites, and are more likely to be performed in older patients. Therefore, complication rates associated with pneumoperitoneum or abdominal entry may actually turn out to be higher for laparoscopic general surgery, making selection of a blind versus open access technique more important. Two direct comparisons of these access approaches in laparoscopic cholecystectomy indicated that an open technique employing a peritoneal cut-down and trocar insertion under direct visualisation was safer than blind insertion of the Veress needle and primary trocar. We also favour the open access technique, believing that the risk for serious visceral or vascular complications is less than that with a blind approach.

Catheterization↗
PubMed1994

The Use of Veress Needle and 10-mm Trocar (VN) Versus Direct Trocar Insertion (DTI) in the Beginning of Laparoscopy

Seven hundred fifty-six women were randomly divided into two groups. Group 1 (378 cases) were operated on via laparoscopy with VN and group 2 (378 cases) with DTI technique. Complications were compared between the two groups. No major complications occurred. Minor complications were: a problem with insufflation of CO2 (19 VN, 2 DTI, P<0.001); more than one insertion of the instrument (18 VN, 13 DTI, NS); need to alter the technique (6 VN, 10 DTI, NS); and penetration of the fascia but not the peritoneum by trocar sleeve (2 VN, 19 DTI, P<0.001). The significant differences found presented no serious problems, and we concluded that both methods were satisfactory.

Journal Article↗
PubMed2006

Safety and efficacy of initial trocar placement in morbidly obese patients.

HYPOTHESIS: The use of a nonbladed trocar with an optical view is a safe and effective method for initial trocar placement for laparoscopic bariatric surgery. DESIGN: Retrospective review of consecutive patients. SETTING: University-associated hospital. PATIENTS: All patients who underwent laparoscopic bariatric surgery from December 2002 to November 2003. INTERVENTION: Initial trocar placement. MAIN OUTCOME MEASURES: Injury and bleeding during initial trocar placement, trocar placement time, and insufflation time. Trocar placement time was defined as the time to place the trocar into the peritoneal cavity (including infiltration of local anesthesia and incision). Insufflation time was defined as time to insufflate the abdomen to a pressure of 10 to 15 mm Hg (including time to place tubing on trocar). RESULTS: There were 228 patients who had no evidence of any bowel or vessel injury during initial trocar placement. In the last 50 patients, average body mass index (calculated as weight in kilograms divided by the square of height in meters) was 47 (range, 35-63). Average trocar placement time was 25 seconds (range, 10-60 seconds), and average insufflation time was 16 seconds (range, 5-25 seconds). In almost all cases, appropriate pneumoperitoneum was established in less than a minute. No correlation was seen between times and body mass index (trocar, P = .56; insufflation, P = .95) or waist-hip circumference (trocar, P = .74; insufflation, P=.48). CONCLUSIONS: Initial trocar placement using a nonbladed trocar with an optical view without prior abdominal insufflation is safe and effective in morbidly obese patients. This method can be applied even in the super obese.

Body Mass Index↗
PubMed2001

Development of an ultrasonically activated trocar system.

BACKGROUND: Although rare, visceral and vascular injuries related to the insertion of conventional laparoscopic trocars may have disastrous consequences. Most of these injuries are due to the high puncture force applied to the trocar. We present the results of an animal laboratory evaluation of a newly developed ultrasonically activated trocar. METHODS: A total of 40 punctures were made in four pigs with an average weight of 53 kg. An 11-mmHg pneumoperitoneum was created through a Veress needle. A 10-mm diameter trocar was inserted in the midline for a laparoscope. A series of five trocars were then inserted on each lateral wall under laparoscopic control. Twenty punctures were made with a conventional reusable 11-mm trocar (CT) whose tip was sharp and conical. Twenty punctures were made with an 11-mm ultrasonically activated trocar (UT), whose fequency was 23.5 KHz and amplitude 150 mm. The cutaneous incision was made large enough so that the skin did not interfere with the trocar insertion. The force applied to the trocar was measured with a push-pull gauge connected to a computer. The following data were recorded: maximal force applied to the trocar to obtain insertion of the tip through the abdominal wall, maximum abdominal pressure increase during trocar insertion, and time for abdominal penetration. RESULTS: The average time needed for trocar penetration was 12.8 s with CT and 4.5 s with UT (p < 0.001). The average maximal force was 6.8 kgF with CT and 0.4 kgF with UT (p < 0.001). The average abdominal pressure increase was 7.6 mmHg with CT and 0.8 mmHg with UT (p < 0.001). At 30 days, no necrosis was found. Pathological findings were similar in both groups. CONCLUSION: Ultrasonically activated trocars required less time and much less force to be inserted. This may be a breakthrough in the safety of trocar insertion.

Animals↗
PubMed2006

Two-trocar laparoscopic varicocelectomy: cost-reduction surgical technique.

OBJECTIVES: To describe the technique of two-trocar laparoscopic varicocelectomy and compare it with the standard three-trocar laparoscopic technique in terms of effectiveness, morbidity, and cosmesis. METHODS: Two matched groups of patients with left varicocele were recruited. Each group included 30 patients. One group underwent three-trocar and the other two-trocar laparoscopic varicocelectomy. The results of the two approaches were compared. RESULTS: No significant differences were found in terms of mean hospital stay or morbidity between the two-trocar and three-trocar techniques. A significant difference was found in the operative time and proportion of patients needing postoperative parenteral narcotic analgesia in favor of the two-trocar technique. In both approaches, the previously infertile patients had a significant improvement in sperm count and motility (P <0.05). Cosmetically, the trocar wound scars were aesthetically superior using the two-trocar technique. CONCLUSIONS: No significant difference was found between two-trocar and three-trocar laparoscopic varicocelectomy in terms of effectiveness and morbidity. The cost of an extra 5-mm disposable trocar in the three-trocar technique and the improved cosmesis after the two-trocar technique have made us prefer the latter technique.

Adult↗
PubMedDate not supplied

A randomized prospective study of radially expanding trocars in laparoscopic surgery.

Trocar injury is one of the most serious and potentially preventable complications of laparoscopic surgery. Use of a blunt rather than a cutting trocar could be expected to lessen the likelihood of this injury. Therefore complications related to laparoscopic port design were studied by comparing conventional cutting trocars with radially expanding (blunt) trocars. A multicenter, prospective, randomized clinical trial was conducted in 250 adult patients undergoing elective laparoscopic procedures at tertiary care centers and community hospitals. The patients were randomly assigned to one of two groups: group C, conventional cutting trocars; or group S, radially expanding trocars. Sixteen surgeons performed 244 elective laparoscopic procedures; six patients were removed from the study. One hundred nineteen patients were assigned to group S and 125 to group C. The groups were similar with regard to age, sex, and type of procedure. The following data were collected: intraoperative complications related to the trocars, abdominal wall bleeding, visceral or vascular injury, other complications, fascial closure, procedure time, trocar site assessment at 4 and 24 hours postoperatively, and visual analog pain scores at 4, 8, 12, and 24 hours postoperatively. Fascial defects from 10 mm or larger trocars in group C were closed; the fascial defects in group S were not closed. The trocar sites were checked for incisional hernias at late follow-up. Mean operating time was not different between the two groups (group S, 92 +/- 73 minutes; group C, 100 +/- 74 minutes). There were no episodes of intraoperative cannula site bleeding in group S compared with 16 episodes in 13 patients (P < 0.001) in group C. Postoperative wound complications were fewer in group S (13 vs. 23; P < 0.05). Although the pain scores were generally lower in group S, the differences were not significant. Only 3% of the patients in group S had fascial defects of 10 mm or greater that had to be closed. Within a follow-up period of 6 to 18 months, there have been no incisional hernias in either group. This study shows that radially expanding trocars are safe and effective, and less likely than conventional trocars to result in intraoperative or postoperative complications. The defects created by the radially expanding trocars do not have to be routinely closed.

Abdominal Muscles↗
PubMed2006

Experience with the optical access trocar for safe and rapid entry in the performance of laparoscopic gastric bypass.

BACKGROUND: In laparoscopic surgery, serious complications caused by the blind insertion of trocars are well known. The open technique is compromised by the leakage of carbon dioxide and can also be time consuming, especially in morbidly obese patients. Our aim was to determine whether the optical access trocar can be used to establish a safe and rapid entry during laparoscopic gastric bypass. METHODS: The data on a single surgeon's experience with 370 laparoscopic gastric bypass procedures during a 4-year period were reviewed. The Optiview trocar was used for all except the initial 21 patients. The entry time for the optical trocar was measured in 10 patients. RESULTS: Of the 370 patients undergoing laparoscopic gastric bypass from November 2000 to September 2004, the initial 21 were treated using the standard Veress needle to create the pneumoperitoneum. The next 22 were treated using the Veress needle to create the pneumoperitoneum, followed by insertion of the optical access trocar in the left upper quadrant as the initial trocar. From this point to the present, the optical access trocar has been inserted without the use of a Veress needle. There have been no trocar-related bowel or vascular injuries in the entire series. The mean optical trocar insertion time was 28 +/- 1.2 s. CONCLUSIONS: This is the first laparoscopic gastric bypass series to report the results of its experience with the optical access trocar. This device provides a safe and rapid technique for placement of the initial trocar for laparoscopic gastric bypass. Insertion of the optical trocar with a 10-mm laparoscope into the left upper quadrant is our procedure of choice for obtaining the pneumoperitoneum in this patient population.

Adult↗