King Khalid University Journal of Health Sciences

: 2022  |  Volume : 7  |  Issue : 1  |  Page : 59--66

Do clinical experience and surgical technique affect outcomes in initial laparoscopic trocar placement? A prospective randomized clinical trial

Mohammed A Bawahab1, Walid Mohamed Abd El Maksoud1, Khaled Said Abbas1, Hassan A Alzahrani1, Abdullah Dalboh1, Fahad S Al-Amri1, Helmuth T Billy2,  
1 Department of Surgery, Faculty of Medicine, King Khalid University, Abha, Saudi Arabia
2 Department of Surgical Education, Community Memorial Hospital, Ventura, California, USA

Correspondence Address:
Dr. Walid Mohamed Abd El Maksoud
Department of Surgery, Faculty of Medicine, King Khalid University, P. O. 641. Abha
Saudi Arabia


Aim: The aim of this study was to compare the intraoperative and postoperative complications of laparoscopic cholecystectomy by closed (supraumbilical Veress needle) versus open infraumbilical technique for initial, first port laparoscopic access. Patients and Methods: Our study included 560 adult patients, who were randomized into four groups (i.e., expert Veress, expert open, junior Veress, or junior open). Time for placement of the first trocar and time to complete the port-site closure were compared in all study groups. The mean operative time for cholecystectomy was compared after successful placement of the initial trocar until removal of the gallbladder. Intraoperative, early, and late postoperative complications were compared. Results: Duration of the initial port placement was significantly shorter among senior compared to junior surgeons. The Veress technique had a significantly shorter duration of port entry, but a longer duration of port-site closure compared to the open technique. Apart from the extraperitoneal insufflation incidents that were significantly more reported by junior surgeons, no significant differences in incidents were reported by senior and junior surgeons between open and closed techniques. Junior surgeons showed a better satisfaction with the open than the closed technique. Conclusions: Both the closed and open techniques for laparoscopic cholecystectomy are equally safe and effective for initial port-site entry whether performed by senior or junior surgeons. Junior surgeons are more satisfied with the open technique than the Veress needle technique, due to a perceived concern of injuring intra-abdominal structures. Therefore, junior surgeons would benefit from additional training during their residency to use both the techniques confidently.

How to cite this article:
Bawahab MA, Maksoud WM, Abbas KS, Alzahrani HA, Dalboh A, Al-Amri FS, Billy HT. Do clinical experience and surgical technique affect outcomes in initial laparoscopic trocar placement? A prospective randomized clinical trial.King Khalid Univ J Health Sci 2022;7:59-66

How to cite this URL:
Bawahab MA, Maksoud WM, Abbas KS, Alzahrani HA, Dalboh A, Al-Amri FS, Billy HT. Do clinical experience and surgical technique affect outcomes in initial laparoscopic trocar placement? A prospective randomized clinical trial. King Khalid Univ J Health Sci [serial online] 2022 [cited 2023 Mar 29 ];7:59-66
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Full Text


Cholecystectomy is one of the most common surgical procedures performed in general surgery.[1],[2],[3] The transformation from open to laparoscopic cholecystectomy began in the early 1990s. Improved techniques in trocar placement, intra-abdominal access, and insufflation contributed to the rapid increase in the popularity of laparoscopic cholecystectomy to where it now dominates as the gold standard technique for operative cholecystectomy.[4],[5]

Intra-abdominal access and the creation of pneumoperitoneum is the initial and perhaps most important step in any laparoscopic procedure. Techniques have evolved from open access to more minimally invasive techniques using Veress needles and optical viewing trocars. The variety of techniques developed can be associated with complications including injuries to gastrointestinal organs or major vessels.[6] Despite advances in initial trocar placement, the rate of major complications associated with intra-abdominal trocar placement has remained the same during the past 25 years. At least 50% of injuries occur during trocar placement, before the commencement of the intended operation.[7],[8] The introduction of the initial laparoscopic port carries the highest incidence of intra-abdominal injury and complication. Caution should be taken regardless of the followed technique during access of the intra-abdominal space, which is commonly either open-access or closed percutaneous entry using the Veress needle. Careful meticulous technique is necessary to avoid injury to intra-abdominal structures.[9],[10] Subsequent introduction of additional operative ports is relatively safe and seldom results in injury, due to the presence of the insufflated abdomen and the advantage of direct visualization.[11]

Several techniques have been developed to assist surgeons with initial trocar entry. Currently, the most commonly utilized are the percutaneous technique, using a Veress needle, and the traditional, open, directly visualized cutdown technique.[12] The closed technique depends on a blind percutaneous access followed by abdominal insufflation. This technique is dependent on the successful access through the subcutaneous fat and the abdominal wall fascia before penetrating through the preperitoneal fat. Once insufflation is obtained, the introduction of the first port can occur without any untoward incidents. If the insufflation has occurred successfully, the intra-abdominal viscera will fall away from the anterior abdominal wall allowing for a safe, although blind, entry of the initial first port.[13] The more traditional open techniques depend on opening the abdominal wall first via a traditional incision, dissection to the anterior abdominal wall fascia, followed by open incision of the fascia, identification of the peritoneum after which incision of the peritoneum allows intra-abdominal access and the introduction of the first port under vision. Insufflation does not occur until successful placement of the trocar has occurred into the abdominal space.[14]

These techniques are significantly different and may affect the incidence of complications, time required to perform the operation, and complexity of the port-site closure at the conclusion of the procedure.[15],[16]

It is still a matter of debate as to which technique should be the preferred way to perform the initial port entry.[16] Although some studies reported that open techniques are safer for the first port entry,[17],[18] the Veress needle technique is common and is also described as a safe, acceptable technique. The Veress needle percutaneous technique has gained popularity largely in other studies due to its easiness and rapidity.[10],[19]

The Cochrane Library had a recent update via a systematic review regarding laparoscopic entry techniques, which concluded that there was insufficient evidence in their review to support the use of one access technique over another. The event rates were low, sample size was insufficient, and study methods were poorly reported. In addition, the risk of associated technique bias in the review could not be eliminated.[20]

Moreover, it has been reported that junior surgeons faced an increased difficulty with laparoscopic entry than expert surgeons.[21] Hence, it is not known which technique of initial port entry is safer in the hands of junior surgeons.

The goal of this study was to compare technical outcomes, intraoperative and postoperative complications, and necessary operative times for using the closed technique (supraumbilical, using percutaneous Veress needle) with the open infraumbilical technique, for successful initial port-site entry by expert or junior surgeons.

 Patients and Methods

This study followed a randomized controlled trial design, with four parallel groups. It included patients who were admitted to Aseer Central Hospital, Abha City, Saudi Arabia, during the period from February 2013 to June 2018 to undergo laparoscopic cholecystectomy.

Eligibility criteria included adult patients (aged ≥18 years), who were scheduled for laparoscopic cholecystectomy due to symptomatic chronic calculous or acute calculous cholecystitis. Patients with previous abdominal surgeries, those who had paraumbilical hernias, or those with body mass index >35 kg/m2 were excluded from the study. In addition, patients for whom the port entry technique was converted to other techniques were excluded from the study.

The minimal sample size for each group was calculated using the sample size calculator[22] to be 108 patients, based on α =0.05, and power = 0.90, and assuming that the complication rate of first port entry was 0.1%.[23]

Preoperative preparation

All patients were subjected to thorough history taking and clinical examination. All necessary laboratory and radiological investigations were performed.

Written informed consent was obtained from all patients regarding the operation and participation in this study. All measures were taken to conceal the identity of the patients.

Patients were randomized into one of the four groups using the sealed, numbered, opaque envelope technique. Group EV included patients who were subjected to Veress needle technique by expert surgeons, whereas Group JV included patients who were subjected to Veress needle technique by junior surgeons. On the other hand, Group EO included patients who were subjected to open technique by expert surgeons and Group JO included patients who were subjected to open technique by junior surgeons. All junior surgeons were supervised by expert surgeons during their operative work. Junior surgeons were the residents at the 5th year of their 5-year residency program of surgery, whereas expert surgeons were surgeons who had at least 5-year postresidency experience.

Four sets of envelopes were prepared for the study groups (i.e., EV, EO, JV, and JO), each containing 140 envelopes, which were sealed and shuffled. A nurse with no relation to the research (M.A.) was asked to choose an envelope just before the operation and to inform the surgeon and the operative nurse as to the initial port entry technique to be used.

A dose of cefuroxime (1 g IV) was given to all patients just before induction of anesthesia.

Operative workup

All patients were operated under general anesthesia. The Veress needle used in this study was ENDOPATH® (length: 120 mm; Ethicon Endo-Surgery, LLC, USA). The ports used for initial entry were ENDOPATH XCEL® Dilating Tip Trocar, 11 mm (Ethicon Endo-Surgery, LLC, USA).

EV and JV groups

Patency and safety of the Veress needle were confirmed before skin incision in all patients. A small incision (about 1 cm) was made just above the umbilicus. Splitting of the fatty subcutaneous layer was performed until reaching the sheath. The needle was introduced until it reached the abdominal cavity. Location was confirmed by two audible clicks as the needle traversed the fascia and peritoneum. Placement was confirmed by the water drop test. Placement of the needle was augmented by hand retraction of the abdominal wall during placement of the access needle to avoid visceral injury. Insufflation was initiated and continued until the desired intra-abdominal pressure was achieved. The needle was withdrawn and the 11-mm port was introduced. Following successful access into the abdominal cavity, the introducer was then withdrawn. The camera was introduced to confirm successful intra-abdominal placement.

EO and JO groups

A Kocher clamp was placed as a retraction device, securing it to the bottom of the umbilicus and retracting anteriorly. A 1-cm vertical incision was made just below the umbilicus [Figure 1]. Splitting of the subcutaneous fat was performed until the location of the umbilicus at the linea alba could be identified. A second Kocher clamp was secured to subcutaneous portion of the umbilicus at the linea alba to hold the lower part of the umbilical stump [Figure 2]. Both the clamps were retracted anteriorly and a 1-cm incision was made through the fascia to reveal the underlying peritoneum [Figure 3]. The peritoneum was punctured using a blunt instrument [Figure 4]. A 1-Vicryl purse-string suture was made around the fascial opening without tightening [Figure 5]. The trocar was then passed through the opening and the introducer was removed [Figure 6]. Gentle traction on the Vicryl purse-string suture was applied to avoid loss of pneumoperitoneum around the trocar. The camera was introduced to ensure correct position and insufflation performed to the desired pressure.{Figure 1}{Figure 2}{Figure 3}{Figure 4}{Figure 5}{Figure 6}

The following datasets were recorded: duration of port entry (from the start of the procedure till the end of insufflation with the first trocar in place), number of trials for entry, complications related to the port introduction, and the time of closure of the same port. Surgeons' satisfaction about the technique was assessed on a 5-point Likert scale, by asking each surgeon to choose between “very satisfied,” “satisfied,” “neutral,” “dissatisfied,” and “very dissatisfied.”

Postoperative period

All patients were monitored during the immediate postoperative period to detect early postoperative complications. Patients were discharged on the same day or on the first postoperative day, unless complications were observed. Patients were followed up at 2 and 4 weeks postoperatively. Any early postoperative complications or wound-related complications were recorded.

Long-term follow-up was performed at 6, 12, and 24 months. Any late postoperative complications, including wound-related complications, were assessed and appropriately recorded.


The primary endpoints were as follows:

Intraoperative complications among the study groups as reported by the surgeons during the operationEarly postoperative complications among the study groups as reported by the surgeons at 2- and 4-week follow-up visitsLate postoperative complications among the study groups as reported by the surgeons during follow-up visits at 6, 12, and 24 months.

The secondary endpoints were as follows:

Participant surgeons' satisfaction grades regarding closed and open techniques immediately at the conclusion of the operation.

Statistical analysis

The statistical analysis was done using the Statistical Package for the Social Sciences (SPSS version 25; SPSS Inc., Chicago, Illinois, USA). Descriptive statistics were applied (frequency and percentage for categorical variables and mean and standard deviation for quantitative variables). To test the significance of differences between the randomized study groups, analysis of variance was applied for quantitative data, whereas the Chi-squared test was applied for qualitative data (Fisher's exact test was alternatively used when appropriate). Statistically significant differences were considered at P < 0.05.

The study was conducted in accordance with items of the CONSORT 2010 checklist.[24]

The research was approved by the Research Ethics Committee of our institution.


The study included 560 patients (215 males and 345 females), who were scheduled for laparoscopic cholecystectomy. Patients were randomized into four groups, each group included 140 patients. Patients' demographic data in each group are shown in [Table 1].{Table 1}

The duration of the first port was significantly shorter among expert surgeons when compared to junior surgeons. The duration of the open technique was significantly longer than the Veress technique among expert and junior surgeons. The duration of closure was, however, significantly longer in the Veress technique compared to the open technique among expert and junior surgeons. Junior surgeons required significantly more attempts at placement of the Veress technique to achieve successful access compared to the expert surgeons. The total duration of the operation was significantly longer among junior surgeons compared to the expert surgeons. There were no significant differences between the total duration in the open and Veress techniques among junior or expert surgeons. The operative and postoperative findings of the studied groups are shown in [Table 2].{Table 2}

Junior surgeons had significantly more incidents of extraperitoneal insufflation when performing the Veress technique than expert surgeons. With respect to intraoperative complications, there were four incidents of trocar-related injuries in the junior surgeon group (three in the open technique and one in the Veress technique). All observed injuries were omental or minor mesenteric tears and did not require conversion to laparotomy. Junior surgeons had five incidents of injuries (four omental/minor mesenteric and one small intestinal injuries) during the percutaneous introduction of the Veress needle compared to two incidents in the expert surgeons' group (one omental and one small intestinal injuries). Apart from the more frequent incidents of extraperitoneal insufflation in the junior surgeon group, there were no significant differences between the study groups.

Postoperative complications, which occurred in the group of junior surgeons, included a single incident of fascial dehiscence with evisceration and two incidents of port-site hernia. These three complications occurred in the Veress group. All complications were successfully managed. There were no other significant differences between the studied groups regarding any other postoperative complications. Operative and postoperative complications are shown in [Table 3].{Table 3}

Surgeons' satisfaction grades regarding closed versus open techniques showed that expert surgeons were significantly more satisfied with the percutaneous Veress technique than junior surgeons. However, there were no significant differences between senior surgeons with respect to open versus Veress techniques. Junior surgeons had a significantly higher satisfaction using the open technique when compared to the percutaneous Veress technique. Surgeons' satisfaction grades in the studied groups and according to intraoperative complications of laparoscopic cholecystectomy are shown in [Table 4] and [Table 5], respectively.{Table 4}{Table 5}


Intra-abdominal access is important when considering the placement of the initial laparoscopic trocar. The most commonly used technique for access is the closed, percutaneous method (Veress) versus the open, cutdown method.[25] Although both techniques are being commonly utilized, there are no studies which could definitely conclude that one technique is superior to the other.[16]

This study explored the differences between these two well-known techniques commonly employed by both the junior and expert surgeons. We also tried to determine if there is a safer technique when utilized by junior or expert surgeons. However, our review of relevant literature could not obtain any supporting evidence that one technique is superior or safer to the other.

Our findings revealed that the time required to perform open-access technique is consistently longer than percutaneous Veress needle technique, whether among senior or junior surgeons. The time required for closure when using the percutaneous Veress technique for access when compared to the open technique was significantly longer among expert and junior surgeons.

Nawaz[26] reported that the mean time needed to create pneumoperitoneum was significantly less in the Veress needle technique than in the open method (4 ± 1 min and 5 ± 1 min, respectively, P < 0.001).

In this study, the total duration of the operation was significantly longer in the junior surgeons' group compared to the expert surgeons' group. This may be explained by the differences in the experience and surgical skills. However, when comparing junior surgeons to expert surgeons, there were no significant differences between the total duration of time required for trocar access when comparing the open and Veress techniques.

Our findings are in accordance with those of Jamil et al.,[18] who reported that the mean times for access and closure with the closed, percutaneous Veress method were higher than the open method. Similarly, the European Association for Endoscopic Surgery stated that the open approach is faster than the closed approach.[27]

Our results suggest that the difference between the duration of initial port entry and closure by junior or expert surgeons in the studied groups is insignificant and does not affect the duration of surgery or the surgical outcome. In addition, differences between surgical techniques in the various open methods are difficult to control when comparing different studies and may account for the discrepancy between our results and those reported by other studies.

Regarding intraoperative complications, there were no significant differences between the studied groups. We assume that the higher incidence of extraperitoneal insufflation among junior surgeons may be attributed to their hesitancy and excess concerns to avoid visceral injuries. Junior surgeons demonstrated a consistent tendency of being less aggressive and more hesitant when introducing the Veress needle.

Nawaz[26] described no significant difference between Veress needle and open technique in laparoscopic cholecystectomy. They reported one case of visceral injury in which ileal mesentery was damaged with the open group (P = 0.316). This injury was managed laparoscopically and no vascular injury was reported in the two groups. Bonjer et al.[28] compared open and closed techniques and reported that the rates of visceral and vascular injuries were 0.08% and 0.07%, respectively, when using percutaneous Veress technique, and 0.05% and 0%, respectively, after open access (P = 0.002). Chapron et al.[29] reported that bowel and major vessel injury rates were 0.04% and 0.01% in the closed technique and 0.19% and 0% in the open technique, respectively. They concluded that during laparoscopic access, open laparoscopy does not reduce the risk of major complications. Ahmad et al., in their systematic review, reported that regarding the comparison of Veress needle versus open-entry technique, there was insufficient evidence to determine whether there were differences in rates of vascular injury. In addition, they concluded that the evidence was insufficient to show whether there were differences between the two groups regarding visceral injury or failed entry.[20]

In our study, junior surgeons encountered a single incident of dehiscence with evisceration (0.7%) and two incidents of port-site hernia (1.4%). Open access for trocar site placement involves a larger incision which is easier to close and easier to re-approximate fascia accounting for a lower complication rate when using open versus percutaneous Veress technique. Currently, there is abundance of fascial closure devices to assist in facilitating better closure of minimally invasive access techniques, which may help in decreasing complications regarding wound closure and long-term hernia rates in the Veress access group.

Wound infection and hematoma occurred in 1 (0.7%) patient and 2 (1.4%) patients, respectively. These results are comparable with those previously reported by other studies. Nawaz.[26] reported that two patients in their open group series (1.3%) had postoperative hematoma at the umbilical port site, whereas none developed this complication in the Veress group (P = 0.154). They also reported 4 (2.6%) patients who presented with surgical-site infection.

In the current study, expert surgeons were almost equally satisfied with both the techniques. On the other hand, junior surgeons showed significantly more satisfaction with open-entry technique compared to the closed-entry percutaneous Veress approach. Most of the neutral, dissatisfied, and very dissatisfied grades occurred when access required more than one attempt of introduction of the Veress needle.

Our results showed that Veress and open-entry techniques are safe when performed by both the expert and junior surgeons. However, there was no clear superiority of outcome with respect to any technique over the other. Similarly, Vilos et al.[30],[31] reported that there is no conclusive evidence that the open-entry technique is better or worse than other entry techniques. The open-entry technique is associated with a lower incidence of vascular injuries. The potential risk of bowel injury seen in open-entry technique can be mitigated if alternative entry sites were chosen in high-risk patients.

Zaman et al.,[32] Ahmad et al.,[20] and Kumar et al.[33] emphasized that surgeons should be competent in performing both the open-entry and percutaneous techniques. Therefore, resident teaching programs should emphasize training of junior surgeons on the Veress needle technique to develop confidence and improve dexterity and to minimize the potential for prolonged access times and intra-abdominal injuries.


Both the closed and open techniques for laparoscopic cholecystectomy are equally safe and effective for initial port-site entry whether performed by senior or junior surgeons. Junior surgeons are more satisfied with the open technique than the Veress needle technique, due to a perceived concern of injuring intra-abdominal structures. Therefore, junior surgeons would benefit from additional training during their residency to use both the techniques confidently.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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