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Method for safe Verres needle entry at the umbilicus, with modification for first trocar entry to reduce the complication rate of first entry
Tehemton Erach Udwadia
Department of Surgery, Grant Medical College and J. J. Hospital; Breach Candy Hospital and Medical Research Centre; Department of Surgery, B. D. Petit Parsee General Hospital; Department of Minimal Access Surgery, P. D. Hinduja National Hospital and Medical Research Centre, Mumbai, Maharashtra, India
|Date of Submission||20-Sep-2020|
|Date of Decision||19-Oct-2020|
|Date of Acceptance||03-Feb-2021|
|Date of Web Publication||09-Apr-2021|
Tehemton Erach Udwadia,
10 Normandie, Carmichael Road, Mumbai - 400 026, Maharashtra
Source of Support: None, Conflict of Interest: None
Background: Initial intraperitoneal access and first trocar entry are responsible for nearly half of all complications of laparoscopic surgery. The purpose of this article is to detail our method of initial intraperitoneal access with Veress needle and first trocar at the umbilicus used over the past 28 years.
Patients and Methods: Since 1990, a single surgeon performed laparoscopic surgery in 7600 patients. From 1992 onward, 6975 patients underwent laparoscopic surgery. On assessment, 739 cases (10.6%) were found unsuitable for Veress needle entry at the umbilicus. The remaining, 6236, patients form the study group for this article. Every patient was operated in the identical, repetitive manner. Every detail was considered important. The method of the first trocar entry is modified to minimise complications of this manoeuvre.
Results: The average time from cleaning umbilicus again to Veress needle tip in peritoneum was 1 min 40 s (25 s–7 min). Out of the 4228 patients in whom no adhesions were observed at first trocar entry (Group 1), the Veress needle insertion was successful at first attempt in 3829 (90.5%) patients, at second attempt in 322 (7.6%) and at third attempt in 30 (0.7%). In the 2008 patients with significant adhesions observed after first trocar entry (Group 2), successful insertion of the Veress needle was achieved at first attempt in 1700 (84.6%) patients, at second attempt in 182 (9%) and at third attempt in 19 (0.9%). In this group, there was one bowel injury (0.05%) and 3 (0.15%) minor vascular injuries. There was no mortality in either group. In the overall series, the Veress needle was successfully introduced in 6082 of the 6236 patients (97.5%) and 154 patients (2.4%) failed Veress needle entry. The incidence of bowel injury in the series was 0.016% and that of minor vascular injuries was 0.048%.
Conclusions: Initial intraperitoneal access must be performed with utmost caution after adequate training and proctorship. This paper stresses with meticulous attention to every detail, this safe, method of initial intraperitoneal access leads to low complication rates.
Keywords: First trocar entry, intraperitoneal access, Veress needle
|How to cite this URL:|
Udwadia TE. Method for safe Verres needle entry at the umbilicus, with modification for first trocar entry to reduce the complication rate of first entry. J Min Access Surg [Epub ahead of print] [cited 2021 Jun 14]. Available from: https://www.journalofmas.com/preprintarticle.asp?id=313458
| ¤ Introduction|| |
The volume and complexity of laparoscopic surgery performed are increasing exponentially in every surgical specialty. Initial intraperitoneal access forms a crucial step of each laparoscopic procedure. While Veress needle entry, open entry and direct trocar entry are comparable established methods of initial intraperitoneal access, there are, in addition, several methods of entry described.,,,, What makes the difference is not the method of entry, but the manner in which the method is perfected and executed.
Literature attempts comparing various methods of initial intraperitoneal access, to ascertain superiority of any one method,, with the same conclusion – all methods are comparable. There are only two instruments which can cause the 50% complication rate at initial intraperitoneal access – the Veress needle and the first trocar., The Veress needle, 2 mm in thickness with a protective inner sheath, if used with training and caution can, at most, cause minor injuries. The trocar, sharp, unprotected and 10.5 mm in thickness, on the other hand, is responsible for the vast majority of major life-threatening complications because it needs considerable force to penetrate the full thickness of the abdominal wall. To accept that 50% or more of all laparoscopy complications occur, over decades, at the very first step of entry, is a negation of surgical progress. That a profession which strives in every sphere of activity for patient safety, yet passively accepts this unchanged complication rate of initial intraperitoneal access at laparoscopy, needs rethinking.
The author started diagnostic laparoscopy in 1972 using a Veress needle. He commenced laparoscopic surgery in 1990 and has an experience of over 7600 cases over 30 years performed in three tertiary care hospitals and one teaching hospital. Our method of initial intraperitoneal access described in great detail in this article has evolved over time and trial and has been standardised since 1992.
| ¤ Patients and Methods|| |
A total of 6975 patients (2962 males and 3274 females) for laparoscopic surgery were seen from 1992. Every patient was assessed for the safest method of entry: [Table 1] shows the various entry methods adopted for the 6975 patients after assessment. Patients in whom the Veress needle was initially placed at Palmer's point, those who required an open entry for initial intraperitoneal access and those who underwent open surgery (10.6% of the total patients) were excluded from this study. The 6236 (89.4%) patients accepted for initial intraperitoneal access with Veress needle and trocar placed at the umbilicus form the study group. Out of these, 4303 (69%) patients had no previous abdominal surgery, while 1933 (31%) had previous abdominal surgery.
|Table 1: Selection of method for initial intraperitoneal access after initial evaluation|
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As this was a retrospective study, approval from the institutional review board was not needed. The parameters studied and recorded were number of attempts required for Veress needle entry, failed entry, extraperitoneal insufflation, bowel injury, vascular injury, organ injury and death.
The method for initial intraperitoneal access described herein is precise and replicable in every patient.
- All patients had prior abdominal and pelvic ultrasound examination to rule out unsuspected pathology and organomegaly
- Written informed consent was obtained from all patients and they passed urine before coming to the operation room (OR)
- General endotracheal anaesthesia was administered and intraoperative monitoring including end-tidal CO2 was instituted
- A nasogastric tube was placed in all patients
- The table height was adjusted for optimal safe trocar entry by the surgeon
- The patient was supine and with 5°Trendlenberg position. The legs were separated for upper abdominal surgery and together for lower abdominal surgery
- The abdomen was prepped and draped, paying special attention to the umbilicus
- Care was taken to keep the Palmer's point in the prepped operative field
- A specific sequence was followed for checking the Veress needle.
- The stopcock was opened
- The needle tip was checked for sharpness
- The pressure required to push the inner tube to expose the tip was checked
- The strength of the spring of the inner tube was checked
- The Veress needle was connected to the insufflator, with the flow set at 1 L/min and the intra-abdominal pressure (IAP) at 10 mmHg, to ensure free flow.
If during the check, the strength of spring of the inner tube was found to be weak, this was rectified before proceeding further. The most common cause of a weak spring action was bending of the soft inner tube during sterilisation, creating friction during movement of the inner tube. This was corrected by dismantling the needle and sliding the inner tube repeatedly in the outer needle, thereby straightening the inner tube.
- The following steps were used in each and every patient to ensure safe insertion of the Veress needle.
- The aorta was palpated
- The umbilicus was carefully cleaned again
- A curved haemostat, pointing downwards, was placed in the depth of the umbilicus to spread it open
- The umbilical skin and caudal subcutaneous tissue were incised exactly in the midline for 1.5 cm with an 11-number blade facing upwards
- The subcutaneous tissue was divided up to the sheath for the length of the incision by blunt, sharp or diathermy dissection as required
- Retractors were placed at 3 and 9 o'clock positions to retract the divided subcutaneous tissue and to display the exposed sheath for the length of the incision [Figure 1]
- The surgeon held the Veress needle like a dart, with the little finger placed against the exposed sheath to act as a stop to forced entry. The needle tip was placed in the midline at the exposed depth of the umbilicus, pointing to the midline of the pelvis with the angle of insertion dependent on the body mass index (BMI). At the time of this step, absolute silence was observed in the OR to allow the 'click' to be heard but, more importantly, to sound an 'alert' call to all in the OR
- The needle was inserted in one movement by gentle dorsiflexion of the wrist. No force was required, nor was used. The little finger functioned as a guard. As the needle entered the peritoneal cavity, with experience, the surgeon was able to (a) feel the 'give' at the entry, (b) feel the recoil of the spring and (c) hear the click of the spring as it thrusted the protective inner tube out
- The needle tip was not moved.
|Figure 1: Depth of umbilicus and adjacent midline sheath exposed incision starting from umbilicus for 1.5 cm. in exact midline caudally, deepened by blunt and sharp dissection to expose the midline sheath the full length of the incisions|
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- As with the pre-insertion routine, a sequence was followed after insertion of the Veress needle in every patient.
- The needle was aspirated with a 5 ml syringe
- The needle was flushed with saline to confirm free flow
- Aspiration was performed to check for return of fluid if any
- A hanging drop test was performed by elevating the retractors to observe a drop of fluid placed on the hub of the Veress needle getting sucked in
- Confirmatory test: The Veress needle was connected to an insufflator with the flow set at 1 L and IAP at 10 mmHg. If there was a free flow of gas and IAP was below 8 mmHg, the needle tip was considered to be in the free peritoneal cavity. At this stage, the retractors were elevated, thereby raising the peritoneum. This resulted in a lower IAP registering on the insufflator
- The flow rate through the narrow Veress needle was kept at no more than 3 L/min and the peritoneum was allowed to distend gradually
- When the IAP reached 12–15 mmHg, a vertical midline slit was made down from the umbilicus to the linea alba, 6–8 mm in length, through the full thickness of the midline sheath from the Veress needle caudally. The raised IAP dilated the full thickness slit and caused the pre-peritoneum to bulge/pout through. The gas insufflation was continued through the Veress needle [Figure 2]
- As IAP approached 17–20 mm Hg, the first trocar was ready for insertion. The direction and angle of the trocar depending on patients' BMI was pre-planned. The Veress needle was removed. The trocar was gripped with the palm giving gentle pressure, the index finger acting as a guard for controlled entry and the thumb mildly rotating the pyramidal tip at the time of the entry. The trocar tip was placed in the middle of the incision in the stretched sheath [Figure 3]. Midline direction and angle of the trocar as per the patients' BMI was checked. Retractors were elevated and the index finger moved down the sheath as a guard. Only gentle palm pressure was required to glide the trocar through the pre-cut sheath into the peritoneum. There was usually no air leak as the 8 mm incision in the sheath tightly gripped the 10.5 mm trocar.
|Figure 2: Sheath adjacent to umbilicus fully incised for 6–8 mm sheath divided for 8mm. from umbilicus caudally. Raised intra-abdominal pressure splits the thick sheath wide, pre-peritoneal tissue pouts through. Gas insufflation continues through Veress needle in peritoneum|
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|Figure 3: Trocar positioned in centre of incision in sheath increasing intra-abdominal pressure has further widened the slit in the sheath. The trocar tip is placed in the centre of the slit. The mid-line direction of trocar and trocar angle as per patient body mass index is checked and maintained. The index finger slides down the trocar to the sheath for control. Gentle palm pressure, mild thumb rotation and the trocar is eased into the peritoneal cavity through the pre-cut incision without any resistance|
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Immediately after the trocar entry, the optic system was inserted and a careful 360° survey was done to ensure there was no iatrogenic injury. Injuries detected on the table have a far better outcome. Once the position of the first trocar was confirmed, the insufflation pressure was lowered to 12 mmHg for the duration of the surgery.
At the end of the procedure, the wide dissection of the sheath allowed its secure closure. The skin was closed with interrupted 4-0 silk sutures.
Initial intraperitoneal access in the obese
It was obtained through a longer skin incision of 2–3 cm. Dissection of subcutaneous fat up to umbilicus and sheath was performed with monopolar cautery. Appropriately sized deeper retractors were used to display the sheath and elevate the abdomen. A full-thickness incision was made in the midline for 6–8 mm from the umbilicus caudally in the sheath. We chose, in the obese, to limit the IAP to 15 mmHg to ensure that the upper abdomen remained soft and compressible [Figure 4]. Using a higher IAP in the obese results in all the gas collecting in the peritoneal cavity above the low-placed umbilicus where it serves no purpose and the abdomen becomes rigid and non-compressible.
|Figure 4: First trocar entry in obese, with intra-abdominal pressure 15 mmHg, Veress needle is withdrawn. Ten degree Trendelenburg, trocar tip in centre of sheath incision, retractors elevated. Assistant exerts strong pressure on soft supra-umbilical gas bubble, pushing gas into pelvis. Index finger is deep in longer, deeper incision against the sheath as guard, the trocar is gently glided in|
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| ¤ Results|| |
The average time taken from the second cleaning of the umbilicus to confirming the position of the tip of the Veress needle in the peritoneum was 1 min 40 s (25 s–7 min).
In 4228 patients, no adhesions were observed at first trocar entry – Group 1 [Table 2]. In this group, the Veress needle insertion was successful at first attempt in 3829 (90.5%) patients, at second attempt in 322 (7.6%) and a third attempt was required in 30 (0.7%). It failed in 47 (1.1%) patients. Extraperitoneal gas insufflation occurred in 14 (0.33%), but there was no bowel, vascular or organ injuries and no mortality.
|Table 2: Number of attempts at Veress needle insertion to gain successful access and complications in 4228 patients without adhesions (group 1)|
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In 2008 patients, significant adhesions were observed at first trocar entry – Group 2 [Table 3]. In this group, successful insertion of the Veress needle was achieved at first attempt in 1700 (84.6%) patients, at second attempt in 182 (9%) and at third attempt in 19 (0.9%). It failed in 107 (5.3%) patients. Extraperitoneal gas insufflation occurred in 27 (1.34%), there was one bowel injury (0.05%) and 3 (0.15%) minor vascular injuries. There was no mortality.
|Table 3: Number of attempts at Veress needle insertion to gain successful access and complications in 2008 patients with significant adhesions (group 2)|
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Combined results of Groups 1 and 2 are shown in [Table 4]. The Veress needle was successfully introduced in 6082 of the 6236 patients (97.5%) and in 154 patients (2.4%) failed Veress needle entry represented a concern for safety. After the failure of two attempts at insertion of the Veress needle, a third attempt was made only in 49 (0.78%) patients. The incidence of bowel injury in the series was 0.016% and the singular injury happened in 1993, early in the series. When viewed through the first trocar, there was blood dripping into the peritoneal cavity. A trocar placed in the right hypochondrium showed that a loop of ileum was hanging like a hammock adherent to the peritoneum on the opposite sides of the umbilicus. The trocar had injured the bowel on one side of the loop for 1 cm and torn and damaged the adjacent mesenteric vessels. The other two vascular injuries were also minor mesenteric vessel injuries, very likely caused by the Veress needle. They were sealed by bipolar coagulation. There were cases of omental injury in form of minor bleeding, or omental emphysema, which were unfortunately not always recorded. None of these were of significance. The omentum was displaced to view and exclude any injury behind it. There were three minor vascular injuries (0.048%).
|Table 4: Number of attempts at Veress needle insertion to gain successful access and complications in 6236 patients (groups 1 and 2)|
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| ¤ Discussion|| |
The purpose of this article is to describe our method of Veress needle entry at the umbilicus. No effort is made to suggest that this method is better than any other method. No one method can be used for all patients, and awareness and comfort with alternate methods are required for patent safety. Hence, in the interest of patient care, 10.6% seen in this study were pre-excluded, not subjected to Veress needle entry at the umbilicus.
The first three words the author heard Prof. Alfred Cuschieri say in the first lecture he heard on laparoscopy were 'Primum non nocere'–'Above all do no harm'. Yet, 30 years later, the very first step of laparoscopy – initial peritoneal access – accounts for about 50% of all complications of laparoscopic surgery, and this complication rate remains unchanged over decades., To bring down this high complication rate, it may be worth understanding some of the responsible factors – mental approach to initial intraperitoneal access being a crucial one. The surgeon's fixation is on the operative procedure. The initial intraperitoneal access, which has the potential for serious complications, is often considered a necessary nuisance. That the first step of entry requires just as much training as any other 'pillar' of the laparoscopic procedure needs to be driven home., Patient safety demands that no laparoscopist be permitted to proceed beyond this first step without training and proficiency. Safety is in training; understanding, experience, cognition, maturity and innovation, for no two patients and no two pathologies are the same.
Only the bony landmarks have fixed anatomy. The umbilicus, commonly used as the main landmark for initial intraperitoneal access, is not fixed in position and needs study in relation to vascular injury. Abdominal lift at the time of needle and trocar entry, frequently advised and practiced, may in fact be counterproductive. The placement of a Veress needle and a port at the Palmer's point is an important method of rescue from a difficult situation.,
The Veress needle first used by R. Palmer for laparoscopy in 1946 is the most commonly used mode of initial intraperitoneal access.,, The Veress needle is a simple yet sophisticated instrument that merits understanding and study. If used without training, caution and mentorship, the use of Veress needle can result in serious complications. The syringe tests to check the tip of Veress needle in the peritoneal cavity take a few seconds to carry out. Many are of the opinion these tests are unnecessary. If the aspiration test is not carried out before peritoneal insufflation, it may result in the intestine being insufflated with gas, or worse still, gas embolism.
Using our method, the Veress needle could be inserted at the first or second attempt in 96.6% of patients. In deference to the complication rate associated with the third attempt at Veress needle insertion, this was attempted in a very small proportion (0.78%) of patients. We do not view failed entry at the umbilicus as a 'complication', rather as an expression of maturity and concern for safety. Palmer's point was used in all the 154 patients (2.4%) in whom a Veress entry at umbilicus failed. There is an important role for small-sized trocar for safer initial intraperitoneal access at Palmer's point. Depending on the availability, a 5 mm, 3 mm or 2 mm trocar was used to survey the peritoneal cavity from Palmer's point and to guide the placement of the subsequent trocars.
For Veress needle and trocar entry, with conventionally performed laparoscopy, the surgeon has to estimate the pressure to be applied as also the distance from the skin to the peritoneum in each individual case. In our method, in every patient, a strip of the umbilicus and the sheath is exposed by retractors through full length of the incision. The possibility of extraperitoneal gas insufflation is reduced as the only fat layer to traverse is under the sheath. We observed extraperitoneal gas insufflation only in 41 (0.65%) patients. More pertinent, having the tip of the Veress needle/trocar right on the sheath makes it far easier and safer to gauge the force and distance required to enter the peritoneal cavity, just from the umbilicus or sheath down.
It must be appreciated that every patient's abdomen reacts and distends differently with gas insufflation. One cannot go blindly only on IAP readings. The 'feel', tension of the abdomen, with experience, is important in deciding the level of IAP, for that patient, for each step. It has been reported that at an IAP of 15 mmHg, the tip of the trocar is in contact with viscera/vessels at just 2–4 kg pressure, and it requires IAP of over 20–25 mmHg for pressure of 4–6 kg required for the trocar to safely enter the peritoneum. High IAP of 25–30 mmHg is advocated for safe first trocar entry but is not necessarily safe. We have never felt the need of excessively high IAP with our method of smooth effortless entry.
We use a 10.5 mm trocar for the first trocar entry and it is always checked for sharpness. A trocar that is not adequately sharp needs far greater pressure to penetrate the abdominal wall, indents the gas bubble steeply and has a far greater chance of an uncontrolled entry. Using our method as the skin has already been incised longer than the diameter of the trocar, it needs no force to penetrate. Furthermore, the 6–8 mm slit dilates to let the trocar slip in. The sharp trocar passes through the subcutaneous tissue, however thick, without significant resistance, and the sharp tip penetrates the pre-peritoneum and peritoneum easily.
The most significant contribution towards safe first trocar entry described in our method is, when the IAP is around 12–15 mmHg during insufflation, elevation of the lateral retractors and retracting the subcutaneous tissue, followed by making a 6–8 mm full-thickness vertical midline slit in the exposed linea alba. The only structure which needs strong force to penetrate is the linea alba in the midline. Our method ensures that the linea alba offers no resistance to the trocar, which can be inserted smoothly and safely without force. This, we feel, allows the trocar to be gently guided into the peritoneal cavity practically with no force. Making this 6–8 mm slit may sound difficult but in practice is fairly simple and safe. With raised IAP, the midline is stretched tight and splits open with a few gentle, light, layer-by-layer vertical strokes of the pointed tip of the 11-number blade slanted almost parallel to the sheath to prevent deep penetration. A strong thick linea alba requires a longer (8 mm) slit for easy trocar entry. At a lower working IAP of 10–12 mmHg, the slit gets smaller and grips the trocar tight, ensuring no air leak. At normal IAP at closure after desufflation, the 8 mm slit at IAP of 15 mmHg shrinks to just 4 mm in size.
Safe surgery is founded on structured surgical training and mentorship, careful patient assessment and selection, developing experience and cognitive skills, adopting a proven repetitive method with attention to every detail and careful post-operative care. Laparoscopic surgery demands synchronised teamwork. With practice, the surgical team enacted each step in this method to choreographed perfection, thus enhancing patient safety.
| ¤ Conclusion|| |
A safe method of Veress needle entry is presented. A surgeon dedicated to patient safety should master this with meticulous adherence to minutest of detail. The method described is simple and easily reproducible with practice. It is within the scope of any careful surgeon who believes in the Hippocratic advise 'Primum non nocere'.
I owe a debt of gratitude, impossible to repay, to one full generation of resident surgeons, over 30 years, in all four hospitals. Without their enthusiasm, energy, motivation and constant push, little would have been accomplished, less would be worthwhile. Every word written in this article is a tribute to them. That most are today held in high esteem by their peers is not surprising, that all have an ethical practice is gratifying.
Also, I thank a full generation of O.R. nurses, especially those in the early gestation period. We learnt together, from each other. They ensured economy in the face of poor finances, (each instrument, telescope, even Veress would last for years), innovated for instruments we did not have, ensured patient safety, tolerated tantrums, overcame crisis on and off the O.R. table and provided advise, anticipation, patience, humor, support, till it was time for tea. They have kept in touch over the decades and still try to mother me.
The entire O.R. team, anaesthetists, bio-medics, technicians and medical colleagues in all four hospitals, particularly Dr. Rita Dalal, Dr. Shanti Swaroop, Dr. Kekobad Mody and Dr. Mangal Jain.
Dr. Gulab Bhagat, Anaesthetist, who has worked with me for over 50 years in two of the hospitals. He has done more than keep the patient alive, he has helped kept me alive.
Dr. Anjali Kanojia, Associate Surgeon Breach Candy Hospital, who over 20 years has been the anchor and core of our O.R. Team.
The COVID-19 pandemic, with the enforced lockdown over 4 months, gave time and leisure to complete this long overdue study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4]