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International Journal of Surgery 8 (2010) 167–172

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International Journal of Surgery

journal homepage: www.thei js .com

Results of laparoscopic cholecystectomy without energized dissection:A prospective study

Brij B. Agarwal a,b,*

a Dr. Agarwal’s Surgery & Yoga, F-81&82, Street 4, Virender Nagar, New Delhi – 110058, Indiab Department of General Surgery, Sir Ganga Ram Hospital, New Delhi – 110060, India

a r t i c l e i n f o

Article history:Received 19 July 2009Accepted 23 November 2009Available online 6 January 2010

Keywords:Energy sourcesEnergized dissectionThermal injuryBile duct injuryAvascularHoly planesLaparoscopic cholecystectomy

* Tel.: þ91 9810124256; fax: þ91 11 25861002.E-mail address: endosurgeon@gmail.comURL: http://www.endosurgeon.org

1743-9191/$ – see front matter � 2009 Surgical Assodoi:10.1016/j.ijsu.2009.11.015

a b s t r a c t

Introduction: Laparoscopic cholecystectomy (LC) a gold standard treatment of symptomatic gall stonedisease has yet to become as safe as open cholecystectomy. The concerns of safety for both surgeon aswell as patient are present even after the passage of ‘‘learning curve’’ phase. Emphasis on experience andtechnique have helped but for the morbidity associated with the use of energy sources. The purpose ofthis study was to evaluate the possibility of avoiding this morbidity by not using energy sources in LC.Material and method: Prospective case series, with a minimum follow up of 1 year. Consecutive, unse-lected patients of symptomatic gall stone disease operated by an experienced laparoscopic surgeon fromJuly 2003–June 2005. Operative, early and late postoperative outcomes were evaluated.Technique: LC was performed by dissecting in avascular Holy planes without using any energy source.Results: LC could be performed safely in all 135 patients. The technique was uniformly applicable irre-spective of gender, age, time of presentation, grade of inflammation, adhesions or any comorbidity. Therewas no hemodynamic instability, conversion, injury manifesting early or late or any mortality.Conclusion: The potential injury from use of energy sources in LC can be avoided as it can be safelyperformed without using any energy source.

� 2009 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

1. Introduction

Laparoscopic cholecystectomy (LC) the gold standard formanaging symptomatic gallbladder (GB) stones disease continuesto be haunted by the concerns of patient morbidity and litigations.1

Technology such as energy sources though a great facilitator in LChas also been a cause of concern.2 It has been implicated in vascularinjuries, biliary leaks, bile duct injuries (BDI) and bowel injuries.3 Ofall the injuries BDI are an iatrogenic catastrophe.4 Despite all theadvances, incidence of BDI is higher than during the era of opensurgery.1 Inexperience, inflammation and aberrant anatomy are therisk factors for BDI which is compounded further by technicalerrors.5 Energized dissection has been recognized as a cause of BDIdue to thermal trauma or devascularization during dissection.6

While the quest for the root cause of BDI in LC continues,7 energysource induced injury has been identified as a serious technicalfactor.5 Energy sources are used for hemostasis while dissecting inLC. Since the cystic artery, an end artery is usually dealt with clipligation. Rest of the dissection can be safely performed by

ciates Ltd. Published by Elsevier Lt

maneuvering within the avascular zone of surgical ‘Holy plane’. Thepurpose of this study was to perform LC without using any energysource and evaluate the results prospectively.

2. Material and method

This work was carried out at an endosurgery facility and supportivemedical gastroenterology infrastructure with necessary approval fromconcerned research and ethics committees.

All symptomatic cholecystolithiasis patients presenting consecu-tively from July 2003 to June 2005, were included without any exclu-sion criteria except for non-suitability for general anesthesia (GA).

Cholecystolithiasis suspected in patients presenting with biliarycolic was confirmed by sonological demonstration of gall stones.Hemato-biochemistry work up was undertaken as advised by theanesthetist. A record was kept for any comorbid condition.

An informed consent was obtained after proper explanationabout the rationale, steps, complications and consequences of theLC.8 The patients were explained about the surgical technique of LCwithout energized dissection and also a possibility of conversion toopen surgery.

d. All rights reserved.

Fig. 1. Cutting omental adhesion.

B.B. Agarwal / International Journal of Surgery 8 (2010) 167–172168

LC was performed by the standard 4-ports technique creating10–12 mmHg Capnoperitoneum by closed technique. Either of5 mm-0 degree, 5 mm-30 degree or 10 mm-0 degree telescope wasused. No energy sources were used, although both electrosurgery aswell as ultrasonic shears were kept ready for use. Drains were notused except in cases of concomitant laparoscopic chol-edocholithotomy (CDLT) for stones refractory to EndoscopicRetrograde Cholangiopancreatography (ERCP).

Standard operating procedure was followed. There was activecross referencing amongst the team by verbalizing the steps ofsurgery.9

Stopping criteria8 for conversion to open surgery were definedas:

- Failure of dissection to progress- Failure to delineate anatomy clearly- Failure to maintain good endovision

Injectable Diclofenac was given at the end of surgery. Oral par-acetamol was then used as the analgesic in a dose of 10 mg/kg givenevery 6–8 h for the first two days and then if required. The patientswere assessed for complete recovery from GA before being allowedany oral fluids.

All patients were given liquids orally as per their desire after 4–6 h of surgery and told to resume their diet the next day. They weredischarged from the hospital after being allowed liquids orally andonce they walked to the toilets and passed urine.

3. End points and their definition

3.1. Operative outcomes

- Peroperative hemodynamic stability as assessed by theanesthetist.

- Bleeding.- Qualitative – defined as blood in surgical field clouding the

endovision or an identifiable bleeder necessitating clipping orligation.

- Quantitative – measured in multiple of 25 ml.- Need for blood transfusion as per anesthetist’s decision.- Any identifiable vascular, biliary, visceral, intestinal or other

injury.- Iatrogenic GB perforation or spillage of its contents.- Need to convert as per the stopping criteria.- Operative time, taken as period of surgery after the placement

of all ports till the closure of skin wounds (Measured inmultiple of 5 min).

3.2. Early postoperative outcomes (up to first 24 h)

- Hemodynamic stability as assessed by monitoring of heart rate,supine blood pressure and urine output, during the hospital stay.

- Postoperative pain (defined as significant if reported by thepatients).

- Intra-abdominal, if so whether whole of abdomen or in rightupper quadrant only.

- Port site pain whether at 5 mm port or 10 mm port site.- Shoulder tip pain.- Nausea needing antiemetic.- Constipation defined as non passage of flatus within 24 h of

surgery.8

- Malaise, postparandial fullness or nausea or vague abdominalpain after 24 h.8

- Length of postoperative hospital stay (measured in hours).- Any mortality.

Follow up after discharge was done by phone interview for first2 days. The patients were asked to visit us on 3rd postoperative dayand followed subsequently.

3.3. Late postoperative outcome

- Clinically apparent biliary leak.- Postoperative jaundice.- Need for rehospitalization.- Persistence of symptoms of biliary colic.- Biochemical evidence of BDI as reflected by altered LFT done at

the end of 3 months.3

- Any mortality from hepatobiliary or related cause in 1 yearfollow up.

4. Technique

After establishing the capnoperitoneum and placement of ports,LC was begun by doing a diagnostic laparoscopy to rule out anyconcomitant pathology.

4.1. The first step

The first step was to establish surgical access to GB and freeing itfrom any adhesions. Adhesion was of two types.

Type 1: Adhesion of viscera to other viscera or parietal perito-neum restricting clear view and access to GBType 2: Adhesions of GB to surrounding structures i.e.omentum, duodenum, colon, intestinal loops or parietalperitoneum.

In both these types of adhesions, an avascular band of tissuecould be identified between any two adherent structures thusrevealing the surgical holy plane (Fig. 1). A small nick was made inthis avascular zone and the adherent structure was gently pushedaway from the GB aided by sharp dissection. In acute cholecystitis,the adherent structures were separated by blunt dissection in theplane between GB and other structure.

4.2. The second step

Fundus of GB was grasped and the GB retracted superolaterally.In case of tense or friable looking GB, the contents of GB wereaspirated. The Hartmann pouch was then held away from midline

Fig. 2. Cutting the cholecystoduodenal fold. Fig. 4. Antero-superior peritoneum of TOC being sweeped.

B.B. Agarwal / International Journal of Surgery 8 (2010) 167–172 169

by another grasper. The cholecystoduodenal peritoneal fold wasidentified and a window made close to GB at the point of maximumarch in this fold (Fig. 2). Thus two leaves of peritoneum, the ante-rosuperior and posteroinferior, covering the Triangle of Calot (TOC)were defined. The posteroinferior leaf of peritoneum was thendissected towards the fundus of GB. This dissection proceeded inthe inferior cholecystohepatic peritoneal fold (Fig. 3). This perito-neum was divided with scissors close to surface of gallbladder. Thisdissection continued towards the GB fundus as far as possible.

The anterosuperior peritoneum of TOC was then teased bya cephalic push superiorly towards the liver. This displayed theanatomy of biliary pedicle in TOC (Fig. 4). The GB pedicle was thendealt with in standard manner. Then the areolar tissue attachingthe neck of GB to undersurface of liver was cut close to GB (Fig. 5)

4.3. The third step

In the third step of LC, separation of GB from liver bed was begun. GBwas gently pushed away from liver by the convexity of scissors. Thisexposed the areolar tissue between GB and liver (Fig. 6). Dissectionwascontinued in this zone of holy plane. The anterosuperior and poster-oinferior peritoneal reflection from GB to liver were cut close to GB. Thefibrous strands in the loose areolar tissue were cut close to GB. Sepa-ration of GB was achieved by continuing this procedure towards thefundus. After separation of GB, the liver bed was observed for bleeding.

Fig. 3. Cutting the posteroinferior leaf of TOC.

Capnoperitoneum was abolished. The GB was then extracted as usual.Capnoperitoneumwas created again. The liver bed was again inspectedfor any evidence of bleeding (Fig. 7). After ensuring the absence ofbleeding, the procedure was completed as usual.

5. Results

A total of 135 patients (30 males and 105 females) includingthose with co-morbidities underwent LC by this technique asshown in Table 1. They were 10–88 years of age (Avg 46 and Mode40). There were patients with all grades of inflammation of GB asshown in Table 2.

5.1. Operative outcome

There was no conversion to open cholecystectomy. All patientsremained hemodynamically stable during the surgery. There wasno bleed affecting the quality of endovision or interfering with thesurgery. Amount of blood loss was as shown in Table 3.

None of the patients required blood transfusion.No vascular, biliary, visceral or bowel injury was encountered.Iatrogenic perforation of GB occurred in 8 patients. This wascaused by the grasping instrument in all cases. There was noperforation of GB by the dissecting scissors.

Fig. 5. Tissue at medial aspect of GB neck being divided.

Fig. 6. The surgical Holy plane of dissection in liver bed.

Table 1Co-morbidity spectrum.

Co – morbid condition No. of patients (Total ¼ 135)

Hypertension (HT) 43Diabetes Mellitus (DM) 27HT þ DM 15Chronic obstructive airway disease 6Rheumatoid Arthritis 3Epilepsy 2Hemolytic Anemia 2Horse shoe kidney 1Chronic Renal Disease 9Hypothyroidism 13Hyperthyroidism 5Preop ERCP (Successful) 12Post ERCP Residual CBD Stone 5

Table 2Spectrum of disease.

Spectrum of disease No. of patient (Total ¼ 135)

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The operating time was as shown in Table 4

5.2. Early postoperative (24 h) outcome

All patients were hemodynamically stable. All the patients weregiven liquids orally with in 6 h of surgery. All the patients reportedpain at the 10 mm port site. This responded well to paracetamoltablet. None of the patients reported any shoulder tip pain. All thepatients resumed soft diet within 24 h. All of them passed flatuswithin 24 h and had normal diet subsequently. None of them hadsignificant malaise, postparandial fullness, nausea or abdominalpain after 24 h. Most of the patients were discharged as day caresurgery cases if operated in morning. In case of late afternoonsurgery, they were discharged the next morning. In case ofa comorbid condition, they were discharged after evaluation by theconcerned physician. Patients undergoing CDLT were dischargedafter removal of the drain. The hospital stay was as shown in Table 5.

5.3. Late postoperative outcome

There was no rehospitalization or biliary leak. There waspersistence of biliary colic in 8 patients, they were evaluated andfound to have CBD stones. All these 8 patients had no CBD stones asper pre-operative evaluation. These were managed successfully

Fig. 7. Appearance of liver bed.

with ERCP on outpatient basis. Two patients had postoperativejaundice. One of these had iatrogenic GB perforation. The jaundicedisappeared within a week and subsequent biochemical andsonographic evaluation were normal. The other patient was 88years old and was found to have periampullary carcinoma. Hedeclined surgical treatment for that and was managed by Gastro-enterologist. He was alive till the end of study period. Liverbiochemistry was normal after 3 months of follow up in all patients.There was no mortality in the study group.

6. Discussion

Energy sources are universally used in LC as an aid to dissectionand hemostasis. A variety of energy sources are available to theendosurgeon but none of them are biologically inert.10 Monopolarelectrosurgical hook is the choice of majority of surgeons.11

Monopolar electrosurgical hook is potentially most harmful.12 Theyare supposed to enhance patient safety but on the contrary theyhave been implicated in injuries to biliary ducts,5 vessels in liverbed,13 duodenum, and body surface burns14 etc. They also playa role in development of biliary strictures.6 Incidence of theseiatrogenic catastrophes is subject to either under-reporting2 orpoor quality of reporting.15

SexMales 30Females 105

Previous Abdominal Surgery 45Upper Abdominal Surgery 06Lower Abdominal Surgery 39

StonesSingle 40Multiple 95

Grade of InflammationAcute cholecystitis 28Chronic cholecystitis 59Empyema GB 33Mucocele of GB 12Perforated/Gangrenous GB 3

Adhesions 73Omental 67Duodenal 28Omental þ Duodenal 22Colonic/Others 6

Post ERCP Residual CBD Stone 5

Table 3Operative blood loss (in multiples of 25 mL).

Type of GB Amount of bleeding (mL)

Acute cholecystitis 25–50Chronic cholecystitis <25Empyema GB 25–50Mucocele of GB 25–50Perforated/Gangrenous GB 50–75

Table 5Hospital Stay (hours).

Clinical spectrum No. Hospital Stay (hours)

Range Mean Mode Median

Total 135 4–168 25.27 18 18Acute Cholecystitis 28 4–48 18.57 6 & 18 18Mucocele GB 12 16–48 32.5 48 33Empyema GB 33 8–72 23.27 18 18Chronic Cholecystitis 59 4–72 20.85 16/18 16Gangrenous GB 3 168 168 168 168Male 30 6–168 37.8 16 18Female 105 4–72 21.7 18 18Single Stone 40 6–168 39 36 36Multiple Stones 95 4–72 19.49 18 18HT 43 4–168 34.6 18 18DM 27 8–72 36.89 18/48/72 36HT þ DM 15 8–72 36.4 72 18Previous upper abdominal surgery 6 12–48 30 12 & 48 30Previous lower abdominal surgery 39 4–72 29.69 18 18Adhesions 73 6–168 31.97 18 18Omental Adhesions 67 6–168 33.67 18 18Duodenal Adhesions 28 6–168 39 18 18Omental þ Duodenal Adhesions 22 6–168 46.09 18 18ERCP 7 8–168 58.29 8/72 72ERCP þ CBD Stone 5 72–168 110.4 72 72

B.B. Agarwal / International Journal of Surgery 8 (2010) 167–172 171

Energy sources are likely to cause more errors in dissection ascompared to sharp dissection.12 Hence, we did all the dissectionwith scissors. In step one of surgery the adhesion were dividedthrough the avascular zone. This avascular zone was universallypresent as the surgical holy plane between two adherent struc-tures. Benign post inflammatory adhesions are largely avascular.This is due to a fine equilibrium between pro and anti – angiogenicmediators so that little new vessel formation occurs.16 The pro –angiogenic mediators are rather inhibited by cyclooxygenaseinhibitors,16 drugs usually prescribed for pre-operative pain reliefin cholecystitis. Hence virtually no angiogenesis occurs in the zoneof benign adhesions as was seen in our study.

The avascular region was identified by tensing the zone ofadhesion achieved by traction –countertraction on the twoadherent structures. In acute cholecystitis the gallbladder could beeasily freed form surrounding structures. This was facilitated by theedema of acute phase as is well known.17 In stage 2 of LC aspirationof a tense GB helps in secure grasping of fundus and Hartmann’spouch.18 Sharp dissection of the peritoneal coat of TOC delineatedthe anatomy of TOC clearly even in cases with severe inflammation.Application of energy raises the temperature of tissues even atdistant locations.19 This may thus denature the proteins leading totheir coagulation. This might lead to fusion of tissue planes as wellas contraction of the area of TOC. By avoiding energy this sequenceswas aborted. This gave us better anatomical dilineation and anapparently wider TOC.

In separation of GB from liver bed, bleeding is a fearedcomplication. This has been attributed to the tributaries of middlehepatic vein (MHV)13 and anastomotic branches of cystic artery.20

The tributaries of MHV are known to be injured by the invisible

Table 4Operative time (in multiple of 5 min).

Clinical spectrum No. Operative time (minutes)

Range Mean Mode Median

Total 135 15–70 31.07 25/30 30Acute Cholecystitis 28 15–35 26.25 30 30Mucocele GB 12 20–40 33.75 40 37.5Empyema GB 33 25–70 39.55 35 35Chronic Cholecystitis 59 15–55 27.1 25 25Gangrenous GB 3 50 50 50 50Male 30 20–70 37 35 35Female 105 15–65 29.37 25 30Single Stone 40 15–65 32.63 30 30Multiple Stones 95 15–70 30.41 25 30HT 43 15–70 36.84 30 30DM 27 20–70 42.78 40 40HT þ DM 15 25–70 49 25/30/55/

65/7055

Previous upper abdominal surgery 6 30 30 30 30Previous lower abdominal surgery 39 20–65 31.92 25 25Adhesions 73 15–70 36.29 40 35Omental Adhesions 67 15–70 35.79 15 35Duodenal Adhesions 28 15–70 41.25 15 50Omental þ Duodenal Adhesions 22 15–70 42.95 15 57.5ERCP 7 25–65 45.71 25/65 50ERCP þ CBD Stone 5 50–55 53 55 55

and involuntary spread of thermal energy from energy sources. Thetributaries of MHV stay away from the GB by about 2–3 mm.13

Avoidance of use of energy sources and limiting the dissection inthe avascular plane of loose alveolar tissue facilitated the bloodlessseparation of GB. This buffer zone of few mm. provided us witha safe margin for sharp dissection. We did not find any anastomoticbranches of cystic artery in our study group. The liver bed wasobserved for any visible source of bleeding after abolishing thecapnoperitoneum. This was done to assess for any reactionaryhemorrhage after the tamponade of capnoperitoneum wasabolished.

All the steps of LC by this technique were further facilitated byabsence of plume which helped in maintaining clear endovision.This potentially minimizes the frequency of instrument reintro-duction and lens cleaning. This helps in better utilization of time.

Judicious use of energy sources is a valid recommendation.8 Butthere is inherent subjectivity in this principle. The need for scru-pulous skills evaluation and respect to anatomy8 are recognized asprerequisites to performing safe LC. The safety of the procedure canbe further enhanced by incorporating the systems approach ofairline industry.21 Precise dissection along appropriate tissueplanes reduces morbidity.22 Sharp dissection is more precise12 andpossible once the proper tissue planes are identified. Thus avoidingthe use of energy sources can only further the interest of patientsafety. This validates the dictum that technology should be usedonly for the benefit to larger interest of patients.23 This will benefitthe society at large and make the LC a procedure performed in‘‘better safe then sorry’’ manner.

7. Conclusion

LC can be done without using any energy source. This techniquealso provides us with a possibility of replacing carbon dioxide (amajor climate concern)24 in creation of pneumoperitoneum.

Conflict of interestNone.

FundingNone.

B.B. Agarwal / International Journal of Surgery 8 (2010) 167–172172

Ethical approvalCleared by the Research & Ethics Committee, Agarwal NursingHome, Janakpuri, New Delhi-110058 INDIA. Dated 08th May 2003.

Acknowledgments

We are grateful to Dr. Strasberg S.M. for his guidance and criticalreview. Our thanks are also due to Ms Pooja Pant for office supportand Mr. Krishna Adit Agarwal and Mr. Nayan Agarwal for the datacompilation, manuscript preparation and online submission.

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