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Meta-Analysis
. 2019 Jan 18;1(1):CD006583.
doi: 10.1002/14651858.CD006583.pub5.

Laparoscopic entry techniques

Gaity Ahmad  1 , Jade Baker #, John Finnerty #, Kevin Phillips, Andrew Watson
Affiliations
Meta-Analysis

Laparoscopic entry techniques

Gaity Ahmad et al. Cochrane Database Syst Rev. .

Abstract

Background: Laparoscopy is a common procedure in many surgical specialties. Complications arising from laparoscopy are often related to initial entry into the abdomen. Life-threatening complications include injury to viscera (e.g. bowel, bladder) or to vasculature (e.g. major abdominal and anterior abdominal wall vessels). No clear consensus has been reached as to the optimal method of laparoscopic entry into the peritoneal cavity.

Objectives: To evaluate the benefits and risks of different laparoscopic entry techniques in gynaecological and non-gynaecological surgery.

Search methods: We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, and trials registers in January 2018. We also checked the references of articles retrieved.

Selection criteria: We included randomised controlled trials (RCTs) that compared one laparoscopic entry technique versus another. Primary outcomes were major complications including mortality, vascular injury of major vessels and abdominal wall vessels, visceral injury of bladder or bowel, gas embolism, solid organ injury, and failed entry (inability to access the peritoneal cavity). Secondary outcomes were extraperitoneal insufflation, trocar site bleeding, trocar site infection, incisional hernia, omentum injury, and uterine bleeding.

Data collection and analysis: Two review authors independently selected studies, assessed risk of bias, and extracted data. We expressed findings as Peto odds ratios (Peto ORs) with 95% confidence intervals (CIs). We assessed statistical heterogeneity using the I² statistic. We assessed the overall quality of evidence for the main comparisons using GRADE methods.

Main results: The review included 57 RCTs including four multi-arm trials, with a total of 9865 participants, and evaluated 25 different laparoscopic entry techniques. Most studies selected low-risk patients, and many studies excluded patients with high body mass index (BMI) and previous abdominal surgery. Researchers did not find evidence of differences in major vascular or visceral complications, as would be anticipated given that event rates were very low and sample sizes were far too small to identify plausible differences in rare but serious adverse events.Open-entry versus closed-entryTen RCTs investigating Veress needle entry reported vascular injury as an outcome. There was a total of 1086 participants and 10 events of vascular injury were reported. Four RCTs looking at open entry technique reported vascular injury as an outcome. There was a total of 376 participants and 0 events of vascular injury were reported. This was not a direct comparison. In the direct comparison of Veress needle and Open-entry technique, there was insufficient evidence to determine whether there was a difference in rates of vascular injury (Peto OR 0.14, 95% CI 0.00 to 6.82; 4 RCTs; n = 915; I² = N/A, very low-quality evidence). Evidence was insufficient to show whether there were differences between groups for visceral injury (Peto OR 0.61, 95% CI 0.06 to 6.08; 4 RCTs; n = 915: I² = 0%; very low-quality evidence), or failed entry (Peto OR 0.45, 95% CI 0.14 to 1.42; 3 RCTs; n = 865; I² = 63%; very low-quality evidence). Two studies reported mortality with no events in either group. No studies reported gas embolism or solid organ injury.Direct trocar versus Veress needle entryTrial results show a reduction in failed entry into the abdomen with the use of a direct trocar in comparison with Veress needle entry (OR 0.24, 95% CI 0.17 to 0.34; 8 RCTs; N = 3185; I² = 45%; moderate-quality evidence). Evidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.59, 95% CI 0.18 to 1.96; 6 RCTs; n = 1603; I² = 75%; very low-quality evidence), visceral injury (Peto OR 2.02, 95% CI 0.21 to 19.42; 5 RCTs; n = 1519; I² = 25%; very low-quality evidence), or solid organ injury (Peto OR 0.58, 95% Cl 0.06 to 5.65; 3 RCTs; n = 1079; I² = 61%; very low-quality evidence). Four studies reported mortality with no events in either group. Two studies reported gas embolism, with no events in either group.Direct vision entry versus Veress needle entryEvidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.39, 95% CI 0.05 to 2.85; 1 RCT; n = 186; very low-quality evidence) or visceral injury (Peto OR 0.15, 95% CI 0.01 to 2.34; 2 RCTs; n = 380; I² = N/A; very low-quality evidence). Trials did not report our other primary outcomes.Direct vision entry versus open entryEvidence was insufficient to show whether there were differences between groups in rates of visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.50; 2 RCTs; n = 392; I² = N/A; very low-quality evidence), solid organ injury (Peto OR 6.16, 95% CI 0.12 to 316.67; 1 RCT; n = 60; very low-quality evidence), or failed entry (Peto OR 0.40, 95% CI 0.04 to 4.09; 1 RCT; n = 60; very low-quality evidence). Two studies reported vascular injury with no events in either arm. Trials did not report our other primary outcomes.Radially expanding (STEP) trocars versus non-expanding trocarsEvidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.24, 95% Cl 0.05 to 1.21; 2 RCTs; n = 331; I² = 0%; very low-quality evidence), visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.37; 2 RCTs; n = 331; very low-quality evidence), or solid organ injury (Peto OR 1.05, 95% CI 0.07 to 16.91; 1 RCT; n = 244; very low-quality evidence). Trials did not report our other primary outcomes.Other studies compared a wide variety of other laparoscopic entry techniques, but all evidence was of very low quality and evidence was insufficient to support the use of one technique over another.

Authors' conclusions: Overall, evidence was insufficient to support the use of one laparoscopic entry technique over another. Researchers noted an advantage of direct trocar entry over Veress needle entry for failed entry. Most evidence was of very low quality; the main limitations were imprecision (due to small sample sizes and very low event rates) and risk of bias associated with poor reporting of study methods.

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Conflict of interest statement

None known for any review author.

Figures

1
1
Study flow diagram.
2
2
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
3
3
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
4
4
Forest plot of comparison: 1 Open‐entry technique vs closed‐entry technique (primary port entry), outcome: 1.2 Vascular injury (major vessels and abdominal wall vessels).
5
5
Forest plot of comparison: 1 Open‐entry technique vs closed‐entry technique (primary port entry), outcome: 1.3 Visceral injury (bladder or bowel).
6
6
Forest plot of comparison: 2 Direct trocar entry vs Veress needle entry (primary port entry), outcome: 2.1 Vascular injury (major vessels and abdominal wall vessels).
7
7
Forest plot of comparison: 2 Direct trocar entry vs Veress needle entry (primary port entry), outcome: 2.2 Visceral injury (bladder or bowel).
8
8
Forest plot of comparison: 2 Direct trocar entry vs Veress needle entry (primary port entry), outcome: 2.4 Failed entry.
1.1
1.1. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 1 Mortality.
1.2
1.2. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 2 Vascular injury (major vessels and abdominal wall vessels).
1.3
1.3. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 3 Visceral injury (bladder or bowel).
1.4
1.4. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 4 Failed entry.
1.5
1.5. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 5 Extraperitoneal insufflation.
1.6
1.6. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 6 Trocar site bleeding.
1.7
1.7. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 7 Trocar site infection.
1.8
1.8. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 8 Incisional hernia.
1.9
1.9. Analysis
Comparison 1 Open‐entry technique vs closed‐entry technique (primary port entry), Outcome 9 Omental injury.
2.1
2.1. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 1 Vascular injury (major vessels and abdominal wall vessels).
2.2
2.2. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 2 Visceral injury (bladder or bowel).
2.3
2.3. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 3 Solid organ injury.
2.4
2.4. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 4 Failed entry.
2.5
2.5. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 5 Extraperitoneal insufflation.
2.6
2.6. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 6 Trocar site infection.
2.7
2.7. Analysis
Comparison 2 Direct trocar entry vs Veress needle entry (primary port entry), Outcome 7 Omental injury.
3.1
3.1. Analysis
Comparison 3 Direct vision entry vs Veress needle entry (primary port entry), Outcome 1 Vascular injury (major vessels and abdominal wall vessels).
3.2
3.2. Analysis
Comparison 3 Direct vision entry vs Veress needle entry (primary port entry), Outcome 2 Visceral injury (bladder or bowel).
3.3
3.3. Analysis
Comparison 3 Direct vision entry vs Veress needle entry (primary port entry), Outcome 3 Trocar site bleeding.
4.1
4.1. Analysis
Comparison 4 Direct vision entry vs open‐entry technique (primary port entry), Outcome 1 Visceral injury (bladder or bowel).
4.2
4.2. Analysis
Comparison 4 Direct vision entry vs open‐entry technique (primary port entry), Outcome 2 Solid organ injury.
4.3
4.3. Analysis
Comparison 4 Direct vision entry vs open‐entry technique (primary port entry), Outcome 3 Failed entry.
4.4
4.4. Analysis
Comparison 4 Direct vision entry vs open‐entry technique (primary port entry), Outcome 4 Trocar site bleeding.
5.1
5.1. Analysis
Comparison 5 Radially expanding (STEP) trocars vs standard (non‐expanding) trocars (primary port entry), Outcome 1 Vascular injury (major vessels and abdominal wall vessels).
5.2
5.2. Analysis
Comparison 5 Radially expanding (STEP) trocars vs standard (non‐expanding) trocars (primary port entry), Outcome 2 Visceral injury (bladder or bowel).
5.3
5.3. Analysis
Comparison 5 Radially expanding (STEP) trocars vs standard (non‐expanding) trocars (primary port entry), Outcome 3 Solid organ injury.
5.4
5.4. Analysis
Comparison 5 Radially expanding (STEP) trocars vs standard (non‐expanding) trocars (primary port entry), Outcome 4 Trocar site bleeding.
6.1
6.1. Analysis
Comparison 6 Comparisons of sites of entry, Outcome 1 Transfundal vs infraumbilical insertion of the Veress needle.
6.2
6.2. Analysis
Comparison 6 Comparisons of sites of entry, Outcome 2 Left upper quadrant vs caudally displaced umbilical insertion of the Veress needle.
7.1
7.1. Analysis
Comparison 7 SILS vs Veress needle entry, Outcome 1 Mortality.
7.2
7.2. Analysis
Comparison 7 SILS vs Veress needle entry, Outcome 2 Visceral injury (bladder or bowel).
7.3
7.3. Analysis
Comparison 7 SILS vs Veress needle entry, Outcome 3 Trocar site bleeding.
7.4
7.4. Analysis
Comparison 7 SILS vs Veress needle entry, Outcome 4 Trocar site infection.
7.5
7.5. Analysis
Comparison 7 SILS vs Veress needle entry, Outcome 5 Incisional hernia.
8.1
8.1. Analysis
Comparison 8 SILS vs Hasson entry technique, Outcome 1 Mortality.
8.2
8.2. Analysis
Comparison 8 SILS vs Hasson entry technique, Outcome 2 Vascular injury (major vessels and abdominal wall vessels).
8.3
8.3. Analysis
Comparison 8 SILS vs Hasson entry technique, Outcome 3 Failed entry (inability to access the peritoneal cavity).
8.4
8.4. Analysis
Comparison 8 SILS vs Hasson entry technique, Outcome 4 Trocar site infection.
8.5
8.5. Analysis
Comparison 8 SILS vs Hasson entry technique, Outcome 5 Incisional hernia.
9.1
9.1. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 1 Lifting vs not lifting the abdominal wall before Veress needle insertion.
9.2
9.2. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 2 Carbon dioxide gas insufflation vs gasless abdominal wall retractor.
9.3
9.3. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 3 Closed technique vs a parallel technique of Veress needle insertion.
9.4
9.4. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 4 Cutting trocar vs blunt trocar.
9.5
9.5. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 5 5‐mm vs 3‐mm secondary port trocars.
9.6
9.6. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 6 Radially expanding (STEP) trocars vs standard (non‐expanding) trocars (secondary port entry).
9.7
9.7. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 7 X‐cone vs Veress needle entry.
9.8
9.8. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 8 X‐cone vs SILS.
9.9
9.9. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 9 IAP 25 mmHg vs IAP 15 mmHg.
9.10
9.10. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 10 IAP 25 mmHg vs IAP 25 mmHg with external compression.
9.11
9.11. Analysis
Comparison 9 Comparisons of other laparoscopic entry techniques for primary or secondary port insertion, Outcome 11 IAP 15 mmHg vs IAP 25 mmHg with external compression.
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References

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    1. TInelli A, Malvasi A, Istre O, Keckstein J, Stark M, Mettler L. Abdominal access in gynaecological laparoscopy: a comparison between direct optical and blind closed access by Veress needle. European Journal of Obstetrics, Gynecology, and Reproductive Biology 2010;148:191‐4. - PubMed
Tinelli 2011 {published data only}
    1. Tinelli A, Malvasia A, Guido M, Tsin DA, Hudelist G, Stark M, et al. Laparoscopy entry in patients with previous abdominal and pelvic surgery. Surgical Innovation 2011;18(3):201‐5. - PubMed
Tinelli 2013 {published data only}
    1. Tinelli A, Malvasi A, Mynbaev OA, Tsin DA, Davila F, Dominguez G, et al. Bladeless direct optical trocar insertion in laparoscopic procedures on the obese patient. Journal of the Society of Laparoendoscopic Surgeons 2013;17(4):521‐8. - PMC - PubMed
Tsimoyiannis 2009 {published data only}
    1. Tsimoyiannis EC, Konstantinos TE, Pappas‐Gogos G, Farantos C. Different pain scores in single transumbilical incision laparoscopic cholecystectomy versus classic laparoscopic cholecystectomy: a randomized controlled trial. Surgical Endoscopy 2010;24:1842‐8. - PubMed
Venkatesh 2007 {published data only}
    1. Venkatesh R, Sundaram CP, Figenshau RS, Yan Y, Andriole GL, Clayman RV, et al. Prospective randomized comparison of cutting and dilating disposable trocars for access during laparoscopic renal surgery. Journal of the Society of Laparoendoscopic Surgeons 2007;11:198‐203. - PMC - PubMed
Vilallonga 2012 {published data only}
    1. Vilallonga R, Barbaros U, Sümer A, Demirel T, Fort JM, González O, et al. Single‐port transumbilical laparoscopic cholecystectomy: a prospective randomised comparison of clinical results of 140 cases. Journal of Minimal Access Surgery 2012;8(3):74‐8. - PMC - PubMed
Villalobos 2014 {published data only}
    1. Villalobos Mori R, Escoll Rufino J, Herrerías González F, Mias Carballal MC, Escartin Arias A, Olsina Kissler JJ. Prospective, randomized comparative study between single‐port laparoscopic appendectomy and conventional laparoscopic appendectomy. Cirugia Espanola 2014;92(7):472‐7. - PubMed
Vilos 2015 {published data only}
    1. Vilos AG, Vilos GA, Abu Rafea B, Oraif A, Abduljabar H. Randomized comparison of Veress needle intraperitoneal placement (VIP) at caudally displaced umbilicus versus left upper quadrant (LUQ) during laparoscopic entry. Journal of Minimally Invasive Gynecology 2015;22(6 Suppl):S104. - PubMed
Yim 2001 {published data only}
    1. Yim SF, Yuen PM. Randomized double‐masked comparison of radially expanding access device and conventional cutting tip trocar in laparoscopy. Obstetrics and Gynecology 2001;97(3):435‐8. - PubMed
Youssef 2015 {published data only}
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Zakerah 2010 {published data only}
    1. Zakherah MS. Direct trocar versus veress needle entry for laparoscopy: a randomized clinical trial. Gynecologic and Obstetric Investigation 2010;69(4):260‐3. - PubMed
Zaman 2015 {published data only}
    1. Zaman M, Singal S, Singal R, Shah A, Sandhu KS, Singh B, et al. Comparison of open and closed entry techniques for creation of pneumoperitoneum in laparoscopic surgery in terms of time consumption, entry‐related complications and failure of technique. World Journal of Laparoscopic Surgery 2015;8:69‐71.

References to studies excluded from this review

Alekberzade 2015 {published data only}
    1. Alekberzade A, Lypnitskiy E, Sundukov I, Badalov J. Early postoperative results of single‐incision laparoscopic cholecystectomy versus four‐port laparoscopic cholecystectomy. 80th Annual Scientific Meeting of the American College of Gastroenterology; 2015; Honolulu (HI) United States. 2015; Vol. 110.
Artis 2014 {published data only}
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Chakravartty 2014 {published data only}
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Dabbagh 2015 {published data only}
    1. Dabbagh N, Soroosh A, Khorgami Z, Shojaeifard A, Jafari M, Abdehgah AG, et al. Single‐incision laparoscopic cholecystectomy versus mini‐laparoscopic cholecystectomy: a randomized clinical trial study. Journal of Research in Medical Sciences 2015;20(12):1153‐9. - PMC - PubMed
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Kim 2009 {published data only}
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Rizwi 2014 {published data only}
    1. Rizwi F, Saleem M, Abid KJ. Outcome of single incision laparoscopic cholecystectomy (SILC) versus conventional four port laparoscopic cholecystectomy for cholelithiasis: a randomized control trial. Pakistan Journal of Medical and Health Sciences 2014;8(1):243‐6.
Sandhu 2009 {published data only}
    1. Sandhu T, Yamada S, Ariyakachn V, Chakrabandhu T, Chongrukust W, Ko‐iam W. Low‐pressure pneumoperitoneum versus standard pneumoperitoneum in laparoscopic cholecystectomy, a prospective randomized clinical trial. Surgical Endoscopy 2009;23:1044‐7. - PubMed
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Shayani‐Nasab 2013 {published data only}
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Singh 2014 {published data only}
    1. Singh D, Jaiswal V, Sonkar AA, Kumar S, Singh S. Randomized control trial of conventional laparoscopic versus single incision laparoscopic cholecystectomy. 11th World Congress of the International Hepato‐Pancreato‐Biliary Association Seoul South Korea 2014;16:115.
Taye 2016 {published data only}
    1. Taye M, Fazal S, Pegu D, Saikia D. Open versus closed laparoscopy: yet an unresolved controversy. Journal of Clinical and Diagnostic Research 2016;10(2):QC04‐QC07. - PMC - PubMed
Warle 2013 {published data only}
    1. Warle MC, Berkers AW, Langenhuijson JF, Jagt MF, Dooper PM, Kloke HJ, et al. Low‐pressure pneumoperitoneum during laparoscopic donor nephrectomy to optimize live donors' comfort. Clinical Transplantation 2013;27(4):478‐83. - PubMed
Watanabe 2016 {published data only}
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Zhao 2015 {published data only}
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References to studies awaiting assessment

Köstü 2016a {published data only}
    1. Köstü B, Kıran G, Ercan Ö, Özer A, Bakacak M. A comparison of skin elevation and fascial elevation in veress needle closed entry method. Journal of the Turkish German Gynecology Association. Conference: 11th Turkish German Gynecology Congress. Istanbul, 2016; Vol. Suppl 1:S137.
Prabakar 2015 {published data only}
    1. Prabakar C. A randomized clinical trial comparing two different methods of trocar placement in gynecologic laparoscopy. Obstetrics and Gynecology. Conference: 63rd Annual Clinical and Scientific Meeting of the American College of Obstetricians and Gynecologists San Francisco, CA United States. 2015:45S‐46S.

References to ongoing studies

NCT00731107 {unpublished data only}
    1. Manley T, Tan J. XCEL Bladeless Trocar Versus Veress Needle: A Randomised Controlled Trial Comparing These Two Entry Techniques in Gynaecological Laparoscopic Surgery. https://clinicaltrials.gov/ct2/show/NCT00731107 (first received 8 August 2008).
NCT02804529 {unpublished data only}
    1. Meng F, Wang C. A Comparison of Three Different Entry Points to Establish the Pneumoperitoneum. https://clinicaltrials.gov/ct2/show/NCT02804529 (first received 17 June 2016).
NCT03306238 {unpublished data only}
    1. Thomas AZ. LAParoscopic Entry Technique in REnal Surgery (LAPRES). https://clinicaltrials.gov/ct2/show/NCT03306238 (first received 11 October 2017).

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References to other published versions of this review

Ahmad 2007a
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