Not applicable.

This protocol focuses on the reconstruction phase of PD using mSLR and follows the guidelines of the ethics committee of the Ruhr-University Bochum, Germany.
NOTE: Patients with a resectable tumor of the pancreatic head, the papillary region or severe refractory chronic calcifying pancreatitis underwent PD. Resectability was present if the tumor had less than 50 % contact to the peripancreatic arteries and did not infiltrate the portal vein or the superior mesenteric vein. Distant metastases in cases of adenocarcinomas were also contraindications for PD. The resection technique in PD is standardized and described in detail elsewhere11,12. It does not affect the type of reconstruction itself.
1. Patient preparation
<ol>
	<li>After the patient has been brought to the operation theatre by the nurses, have the anesthesiologist start the anesthesia. Monitor the depth of anesthesia throughout the operation by the anesthesiologist including continuous check of the vital signs.</li>
</ol>
2. Establishing the indication for mSLR
<ol>
	<li>Confirm the indication for a mSLR after the resection phase in PD. Construct a mSLR in cases of a high-risk pancreatic remnant characterized by soft and fragile pancreatic tissue and/or a tiny main pancreatic duct with a diameter of 1-2 mm.</li>
	<li>Palpate the pancreas to determine subjectively whether the pancreatic texture is soft or hard. Use a Shore durometer to measure the pancreatic texture. Shore units &#60; 40 are characteristic for soft pancreata.</li>
</ol>
3. Reconstruction phase: mobilization of the jejunal loop
<ol>
	<li>Resect the first 10 inches of the jejunum to provide enough length of the mesentery. The jejunum follows the duodenum and begins after the ligament of Treitz.</li>
	<li>Advance the loop into the right upper abdominal quadrant through a wide slit in the transverse mesocolon distal to the right colic artery.</li>
	<li>Close the slit with an interrupted polypropylene 4 &#8211; 0 suture.</li>
	<li>Oversew the stapled line with a continuous PDS 5-0 suture.</li>
</ol>
4. Reconstruction phase: pancreaticojejunostomy
<ol>
	<li>Position the jejunal loop as demonstrated in Figure 1 (&#8220;modified single-loop reconstruction&#8221;) to construct an end-to-side pancreaticojejunostomy.</li>
	<li>Create a double-layer, end-to-side, duct-to-mucosa PJ using an interrupted polydioxanone (PDS) 5-0 suture for the outer layer and interrupted polypropylene 5-0 suture for the inner layer.</li>
	<li>Use interrupted sutures between the pancreatic duct and the jejunal mucosa for the inner layer. Construct the outer layer with single sutures between the pancreatic parenchyma/capsule and the seromuscular layer of the jejunal loop.</li>
</ol>
5. Preparation of the long jejunal limb and jejunojejunostomy
<ol>
	<li>Choose a jejunal segment between the PJ and HJ (which will be constructed afterwards), which measures 25&#8211;35 cm instead of 10 cm as in conventional single-loop reconstruction. Create the jejuno-jejunostomy before or after construction of the HJ.</li>
	<li>Now construct an additional side-to-side jejunojejunal anastomosis at the lowest point between the afferent and efferent limbs of the HJ. Begin by placing marking sutures at the sites of the jejuno-jejunostomy with single PDS 5-0 stitches.</li>
	<li>Perform the intestinal anastomosis in a continuous double-layer PDS 5-0 suture technique. Construct the outer layer of the backwall with a continuous seromuscular suture. Perform the inner layer of the backwall with a continuous suture with stitching of all jejunal layers on both sides. Construct the inner layer and the outer layer of the front wall in the same way.</li>
	<li>Ensure that the anastomosis is sufficiently wide &#8211; about 1 inch. This allows good flow of bile and pancreatic secretions even in the early postoperative period when themucosa is edematous and may obstruct a narrow anastomosis. Close the slit around the jejunal loop using interrupted polypropylene 5-0 sutures.</li>
</ol>
6. Reconstruction phase: hepaticojejunostomy
<ol>
	<li>Use a single-layer interrupted or continuous PDS 5-0 suture for construction of the HJ. Use interrupted sutures especially for tiny ducts. Ensure that the stitches enclose all jejunal layers and all layers of the common bile duct.</li>
	<li>Splint thin-walled and tiny common bile ducts with an externally diverted T-tube.</li>
</ol>
7. Reconstruction phase: duodenojejunostomy
<ol>
	<li>Reconstruct the intestinal passage with an end-to-side, double-layer duodeno(pyloro-)jejunostomy using continuous PDS 4-0 sutures.</li>
	<li>Construct continuous seromusculary sutures for the outer layer of the back- and front wall as described in step 5.3. Use continuous sutures with stitching of all duodenojejunal layers for the inner layers of the anastomosis.</li>
</ol>
8. Management of drainages, postoperative medical treatment and POPF - monitoring
<ol>
	<li>At the end of the surgery, place 2 intraabdominal soft silicone drains in the vicinity of the HJ and PJ. Channel them separately through the skin of the right and left middle abdomen.</li>
	<li>Apply subcutaneous octreotide 100 &#181;g three times a day for 7 days after surgery. Use pasireotide as an alternative.</li>
	<li>Determine pancreatic amylase and lipase activity in the drain fluid every 48 h beginning on postoperative day 3.</li>
	<li>Discharge the patient once they have recovered from surgery &#8211; usually around postoperative day 21. Ensure that the drainages have been removed, the patient is fully mobile and able to eat regularly.</li>
	<li>Perform follow-up investigations including computed-tomography of the abdomen, magnet-resonance-cholangiopancreatography and esophagogastroscopy at least 6, 12 and 24 months after surgery to rule out tumor recurrence, metastases and anastomotic ulcers. The tumor marker carbohydrate antigen 19 &#8211; 9 must be determined as well.</li>
</ol>

<ol>
	<li>Cameron, J. L., He, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+thousand+consecutive+pancreaticoduodenectomies.">Two thousand consecutive pancreaticoduodenectomies.</a> Journal of American College of Surgeons. 220 (4), 530-536 (2015).</li><li>Keck, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pancreatogastrostomy+Versus+Pancreatojejunostomy+for+RECOnstruction+After+PANCreatoduodenectomy+(RECOPANC,+DRKS+00000767):+Perioperative+and+Long-term+Results+of+a+Multicenter+Randomized+Controlled+Trial.">Pancreatogastrostomy Versus Pancreatojejunostomy for RECOnstruction After PANCreatoduodenectomy (RECOPANC, DRKS 00000767): Perioperative and Long-term Results of a Multicenter Randomized Controlled Trial.</a> Annals of Surgery. 263 (3), 440-449 (2016).</li><li>Deng, L. H., Xiong, J. J., Xia, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolated+Roux-en-Y+pancreaticojejunostomy+versus+conventional+pancreaticojejunostomy+after+pancreaticoduodenectomy:+a+systematic+review+and+meta-analysis.">Isolated Roux-en-Y pancreaticojejunostomy versus conventional pancreaticojejunostomy after pancreaticoduodenectomy: a systematic review and meta-analysis.</a> Journal of Evidence Based Medicine. 10 (1), 37-45 (2017).</li><li>Klaiber, U., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Meta-analysis+of+complication+rates+for+single-loop+versus+dual-loop+(Roux-en-Y)+with+isolated+pancreaticojejunostomy+reconstruction+after+pancreaticoduodenectomy.">Meta-analysis of complication rates for single-loop versus dual-loop (Roux-en-Y) with isolated pancreaticojejunostomy reconstruction after pancreaticoduodenectomy.</a> British Journal of Surgery. 102 (4), 331-340 (2015).</li><li>Eshmuminov, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systematic+review+and+meta-analysis+of+postoperative+pancreatic+fistula+rates+using+the+updated+2016+International+Study+Group+Pancreatic+Fistula+definition+in+patients+undergoing+pancreatic+resection+with+soft+and+hard+pancreatic+texture.">Systematic review and meta-analysis of postoperative pancreatic fistula rates using the updated 2016 International Study Group Pancreatic Fistula definition in patients undergoing pancreatic resection with soft and hard pancreatic texture.</a> HPB (Oxford). 20 (11), 992-1003 (2018).</li><li>Ke, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+prospective,+randomized+trial+of+Roux-en-Y+reconstruction+with+isolated+pancreatic+drainage+versus+conventional+loop+reconstruction+after+pancreaticoduodenectomy.">A prospective, randomized trial of Roux-en-Y reconstruction with isolated pancreatic drainage versus conventional loop reconstruction after pancreaticoduodenectomy.</a> Surgery. 153 (6), 743-752 (2013).</li><li>El Nakeeb, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolated+Roux+loop+pancreaticojejunostomy+versus+pancreaticogastrostomy+after+pancreaticoduodenectomy:+a+prospective+randomized+study.">Isolated Roux loop pancreaticojejunostomy versus pancreaticogastrostomy after pancreaticoduodenectomy: a prospective randomized study.</a> HPB (Oxford). 16 (8), 713-722 (2014).</li><li>Tani, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Randomized+clinical+trial+of+isolated+Roux-en-Y+versus+conventional+reconstruction+after+pancreaticoduodenectomy.">Randomized clinical trial of isolated Roux-en-Y versus conventional reconstruction after pancreaticoduodenectomy.</a> British Journal of Surgery. 101 (9), 1084-1091 (2014).</li><li>Machado, M. C., da Cunha, J. E., Bacchella, T., Bove, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+technique+for+the+reconstruction+of+the+alimentary+tract+after+pancreatoduodenectomy.">A modified technique for the reconstruction of the alimentary tract after pancreatoduodenectomy.</a> Surgery Gynecology Obstetrics. 143 (2), 271-272 (1976).</li><li>Aghalarov, I., Herzog, T., Uhl, W., Belyaev, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+single-loop+reconstruction+after+pancreaticoduodenectomy+reduces+severity+of+postoperative+pancreatic+fistula+in+high-risk+patients.">A modified single-loop reconstruction after pancreaticoduodenectomy reduces severity of postoperative pancreatic fistula in high-risk patients.</a> HPB (Oxford). 20 (7), 676-683 (2018).</li><li>Marangoni, G., Morris-Stiff, G., Deshmukh, S., Hakeem, A., Smith, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modern+approach+to+teaching+pancreatic+surgery:+stepwise+pancreatoduodenectomy+for+trainees.">A modern approach to teaching pancreatic surgery: stepwise pancreatoduodenectomy for trainees.</a> Journal of Gastrointestinal Surgery. 16 (8), 1597-1604 (2012).</li><li>. Pyloruserhaltende Duodenohemipankreatektomie nach Traverso-Longmire mit T-Drainage (pp-Whipple) Available from: <a target="_blank" href="https://www.webop.de/Allgemein-und-Viszeralchirurgie/Pankreas-und-Milz/Pyloruserhaltende-Duodenohemipankreatektomie-nach-Traverso-Longmire-mit-T-Drainage-pp-Whipple">https://www.webop.de/Allgemein-und-Viszeralchirurgie/Pankreas-und-Milz/Pyloruserhaltende-Duodenohemipankreatektomie-nach-Traverso-Longmire-mit-T-Drainage-pp-Whipple</a> (2019)</li><li>Machado, M. C., Machado, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systematic+use+of+isolated+pancreatic+anastomosis+after+pancreatoduodenectomy:+Five+years+of+experience+with+zero+mortality.">Systematic use of isolated pancreatic anastomosis after pancreatoduodenectomy: Five years of experience with zero mortality.</a> European Journal of Surgical Oncology. 42 (10), 1584-1590 (2016).</li><li>Pescio, G., Cariati, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+reconstructive+method+after+pancreaticoduodenectomy:+the+triple+Roux+on+a+"P"+loop.+Rationale+and+radionuclide+scanning+evaluation.">A new reconstructive method after pancreaticoduodenectomy: the triple Roux on a "P" loop. Rationale and radionuclide scanning evaluation.</a> HPB Surgery. 9 (4), 223-227 (1996).</li><li>Kingsnorth, A. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+and+function+of+isolated+Roux+loop+pancreaticojejunostomy+after+Whipple's+pancreaticoduodenectomy.">Safety and function of isolated Roux loop pancreaticojejunostomy after Whipple's pancreaticoduodenectomy.</a> Annals of the Royal College of Surgeons of England. 76 (3), 175-179 (1994).</li><li>Jester, A. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Impact+of+Hepaticojejunostomy+Leaks+After+Pancreatoduodenectomy:+a+Devastating+Source+of+Morbidity+and+Mortality.">The Impact of Hepaticojejunostomy Leaks After Pancreatoduodenectomy: a Devastating Source of Morbidity and Mortality.</a> Journal of Gastrointestinal Surgery. 21 (6), 1017-1024 (2017).</li><li>Funovics, J. M., Zoch, G., Wenzl, E., Schulz, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progress+in+reconstruction+after+resection+of+the+head+of+the+pancreas.">Progress in reconstruction after resection of the head of the pancreas.</a> Surgery Gynecology Obstetrics. 164 (6), 545-548 (1987).</li><li>Jover, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Results+of+defunctionalized+jejunal+loop+after+pancreaticoduodenectomy.">Results of defunctionalized jejunal loop after pancreaticoduodenectomy.</a> Cirurgia Espanola. 80 (6), 373-377 (2006).</li><li>Albertson, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pancreaticoduodenectomy+with+reconstruction+by+Roux-en-Y+pancreaticojejunostomy:+no+operative+mortality+in+a+series+of+25+cases.">Pancreaticoduodenectomy with reconstruction by Roux-en-Y pancreaticojejunostomy: no operative mortality in a series of 25 cases.</a> The Southern Medical Journal. 87 (2), 197-201 (1994).</li></ol>

The authors have nothing to disclose.

To date, POPF contributes significantly to the postoperative morbidity following PD1.
A mixture of bile and pancreatic juice can lead to mutual activation of both secretions, increasing their adverse effects on the PJ or the HJ9,13,14,15,16. Cytotoxic activity of activated phospholipase A2, which converts bil...

Pancreaticoduodenectomy (PD) is considered a sophisticated surgical procedure. While mortality has decreased over the last decades, morbidity still remains high1. The most frequent and feared complication is the postoperative pancreatic fistula (POPF), which occurs in over 20% of operations2,3,4,5. POPF can lead to subsequent complications such as postpancreatectomy hemorrhage, delayed gastric emptying, intraabdominal abscess and sepsis. Increased hospital costs, prolonged hospital stay, and delayed initiation of chemotherapy in cancer patients have a dramatic socioeconomic impact2,3,4.
Different surgical approaches have been introduced in the last decades to decrease the frequency and severity of POPF. One of those is the double-loop reconstruction (DLR) with isolated Roux-en-Y loops for the biliary and pancreatic anastomoses. Separating pancreatic juice from bile is thought to decrease the detrimental effects of mutually activated secretions on the pancreaticojejunostomy (PJ). Results in the literature have been encouraging6,7,8. However, operative time is significantly prolonged with DLR4,9.
We here introduce the technique of modified single-loop reconstruction (mSLR) during PD to separate pancreatic secretion from bile compared to the conventional single-loop reconstruction (SLR, Figure 1). In this method, a single long small-bowel loop is used for the construction of the hepaticojejunostomy (HJ) and PJ. A side-to-side anastomosis between the afferent and efferent limb of the HJ facilitates isolated flow of bile and pancreatic secretions. The first promising results confirming decreased mortality and morbidity in patients with high-risk pancreata were reported by our group in 201810.
This method reduces the severity of POPF by separating pancreatic fluid and bile without prolonging the duration of surgery significantly compared to the double-loop reconstruction.

<table>
	<tbody>
		<tr>
			<td>Alexis O XXL</td>
			<td>Applied medical</td>
			<td>C8405</td>
			<td></td>
		</tr>
		<tr>
			<td>Bauchtuch Gr&#252;n 10x90</td>
			<td>Nobatrast</td>
			<td>603219</td>
			<td>abdominal compress</td>
		</tr>
		<tr>
			<td>Bauchtuch Gr&#252;n 45x45</td>
			<td>Nobatrast</td>
			<td>607544</td>
			<td>abdominal compress</td>
		</tr>
		<tr>
			<td>GIA 60mm-3.8mm</td>
			<td>Covidien/Medtronic</td>
			<td>GIA6038S</td>
			<td></td>
		</tr>
		<tr>
			<td>GIA Loading Unit</td>
			<td>Covidien/Medtronic</td>
			<td>GIA6038L</td>
			<td></td>
		</tr>
		<tr>
			<td>OP-Flex Yankauer</td>
			<td>Unomedical</td>
			<td>34094182</td>
			<td>suction device</td>
		</tr>
		<tr>
			<td>Pr&#228;pariertupfer-Set</td>
			<td>Fuhrmann</td>
			<td>32019</td>
			<td>sterile swab</td>
		</tr>
		<tr>
			<td>Schlinggazetupfer 30x40</td>
			<td>Fuhrmann</td>
			<td>32016</td>
			<td>sterile swab</td>
		</tr>
		<tr>
			<td>Telescopic Smoke Pencil</td>
			<td>LiNA Medical</td>
			<td>SHK-TSP-CL</td>
			<td>electro cautery</td>
		</tr>
		<tr>
			<td>Thermocover ECO</td>
			<td>PEMAX</td>
			<td>TC43-75EC2</td>
			<td>bowel cover</td>
		</tr>
		<tr>
			<td>Whipple-Set</td>
			<td>M&#246;lnlycke</td>
			<td>97016042-00</td>
			<td></td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Drainages:</td>
		</tr>
		<tr>
			<td>Drainagebeutel</td>
			<td>Coloplast</td>
			<td>?</td>
			<td>drainagebag</td>
		</tr>
		<tr>
			<td>Silikon-Kapillardrainage</td>
			<td>AsidBonz</td>
			<td>551012</td>
			<td>capillary drainage</td>
		</tr>
		<tr>
			<td>Trichteransatz f&#252;r T-Rohr</td>
			<td>R&#252;sch</td>
			<td>333169-000025</td>
			<td>2,5 mm</td>
		</tr>
		<tr>
			<td>T-Rohr nach Kehr</td>
			<td>R&#252;sch</td>
			<td>423600-000025</td>
			<td>t-tube 2,5 mm</td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Sutures:</td>
		</tr>
		<tr>
			<td>Ethiloop 2mm 2x45cm</td>
			<td>Ethicon</td>
			<td>EH387</td>
			<td>loop</td>
		</tr>
		<tr>
			<td>Mersilene 0 FSL</td>
			<td>Ethicon</td>
			<td>EH7637</td>
			<td>fixation of the drainage</td>
		</tr>
		<tr>
			<td>PDS 1 CT</td>
			<td>Ethicon</td>
			<td>PDP9234</td>
			<td>suturing of the fascia</td>
		</tr>
		<tr>
			<td>Vicryl 2-0 , 6x45cm</td>
			<td>Ethicon</td>
			<td>VCP1226</td>
			<td>for ligature</td>
		</tr>
		<tr>
			<td>Vicryl 2-0 SHplus, 8x70</td>
			<td>Ethicon</td>
			<td>VCP7850</td>
			<td>for ligature</td>
		</tr>
		<tr>
			<td>Vicryl 3-0 MH-1plus</td>
			<td>Ethicon</td>
			<td>VCP245</td>
			<td>subcutaneous suture</td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Pancreatic anastomoses:</td>
		</tr>
		<tr>
			<td>Prolene 5-0 c1</td>
			<td>Ethicon</td>
			<td>8890</td>
			<td>6 x</td>
		</tr>
		<tr>
			<td>PDS 5.0 RB-1plus</td>
			<td>Ethicon</td>
			<td>X1153</td>
			<td>2 x Multipack</td>
		</tr>
		<tr>
			<td>Prolene 4-0 RB-1</td>
			<td>Ethicon</td>
			<td>8871</td>
			<td>2 x holding sutures</td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Hepaticojejunostomy:</td>
		</tr>
		<tr>
			<td>Prolene 5-0 c1</td>
			<td>Ethicon</td>
			<td>8890</td>
			<td>2 x holding sutures</td>
		</tr>
		<tr>
			<td>PDS 5-0 c1</td>
			<td>Ethicon</td>
			<td>PDP1013</td>
			<td>7 x</td>
		</tr>
		<tr>
			<td>PDS 6-0 c1</td>
			<td>Ethicon</td>
			<td>PDP1012</td>
			<td>1 x mucosa fixation sutures</td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Gastrojejunostomy:</td>
		</tr>
		<tr>
			<td>PDS 4-0 SH-1 plus</td>
			<td>Ethicon</td>
			<td>X1154</td>
			<td>1 x Multipack</td>
		</tr>
		<tr>
			<td colspan="4"></td>
		</tr>
		<tr>
			<td colspan="4">Jejuno-Jejunostomy</td>
		</tr>
		<tr>
			<td>Ligasure</td>
			<td>Covidien</td>
			<td>LS1520</td>
			<td></td>
		</tr>
		<tr>
			<td>PDS 5-0 RB-1 plus</td>
			<td>Ethicon</td>
			<td>X1153</td>
			<td>1 x Multipack</td>
		</tr>
		<tr>
			<td>Prolene 2-0 SH</td>
			<td>Ethicon</td>
			<td>8833</td>
			<td>Vessel-suture, etc.</td>
		</tr>
		<tr>
			<td>Prolene 3-0 SH</td>
			<td>Ethicon</td>
			<td>8832</td>
			<td>Cystic duct, cystic artery</td>
		</tr>
		<tr>
			<td>Prolene 4-0 RB-1</td>
			<td>Ethicon</td>
			<td>8871</td>
			<td>2 mal suturing of the slit in the meso</td>
		</tr>
	</tbody>
</table>

modified single-loop reconstruction for pancreaticoduodenectomy

Modified single-loop reconstruction in pancreaticoduodenectomy separates pancreatic secretion from bile. It is performed in cases of high-risk pancreatic remnants to reduce the severity of postoperative pancreatic fistulas and moreover the overall postoperative morbidity. This reconstruction technique is characterized by an extra-long jejunal loop for the construction of the pancreaticojejunostomy and hepaticojejunostomy. The longer distance between these anastomoses and an additional jejuno-jejunostomy between the afferent and efferent limb of the hepaticojejunostomy separate the fluids and prevent backflow of bile towards the pancreaticojejunostomy. Thus, the secretions cannot activate each other and aggravate an existing anastomotic leakage. We observed a reduced rate of severe postoperative pancreatic fistulas after modified single-loop reconstruction compared to conventional single loop reconstruction. The technique is easy to perform, safe, and less time-consuming than a traditional double-loop reconstruction.

Every patient undergoing PD underwent an investigation of the pancreatic tissue to evaluate the indication for mSLR. High-risk pancreatic remnants (i.e., soft pancreatic tissue and a tiny main pancreatic duct) were reconstructed using a modified single loop whenever possible.
We identified 50 patients with high risk pancreatic tissue and a small main pancreatic duct. All of them underwent mSLR. The mean age was 63 &#177; 13 years old. The male/female ratio was 17:33. Indications for surgery we...

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Modified Single-Loop Reconstruction for Pancreaticoduodenectomy

The technique of modified single-loop reconstruction following pancreaticoduodenectomy separates pancreatic secretion from bile, thus reducing the severity of POPF without prolonging the duration of surgery.

Modified single-loop reconstruction in pancreaticoduodenectomy separates pancreatic secretion from bile. It is performed in cases of high-risk pancreatic ...

modified-single-loop-reconstruction-for-pancreaticoduodenectomy

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

7.3K Views.  Ruhr University Bochum. The technique of modified single-loop reconstruction following pancreaticoduodenectomy separates pancreatic secretion from bile, thus reducing the severity of POPF without prolonging the duration of surgery.

Video: Modified Single-Loop Reconstruction for Pancreaticoduodenectomy

Modified Technique for Coronary Artery Ligation in Mice

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI we need better knowledge about pathophysiology of myocardial ischemia. This knowledge may be valuable to define new therapeutic targets for innovative cardiovascular therapies4. Experimental MI model in mice is an increasingly popular small-animal model in preclinical research in which MI is induced by means of permanent or temporary ligation of left coronary artery (LCA)5. In this video, we describe the step-by-step method of how to induce experimental MI in mice.
The animal is first anesthetized with 2% isoflurane. The unconscious mouse is then intubated and connected to a ventilator for artificial ventilation. The left chest is shaved and 1.5 cm incision along mid-axillary line is made in the skin. The left pectoralis major muscle is bluntly dissociated until the ribs are exposed. The muscle layers are pulled aside and fixed with an eyelid-retractor. After these preparations, left thoracotomy is performed between the third and fourth ribs in order to visualize the anterior surface of the heart and left lung. The proximal segment of LCA artery is then ligated with a 7-0 ethilon suture which typically induces an infarct size ~40% of left ventricle. At the end, the chest is closed and the animals receive postoperative analgesia (Temgesic, 0.3 mg/50 ml, ip). The animals are kept in a warm cage until spontaneous recovery.

The surgical procedure used to induce experimental myocardial infarction in mice begins with left thoracotomy between the third and the fourth ribs in order to visualize the anterior surface of the heart and left lung. The left coronary artery is ligated, the chest is closed and the mouse is allowed to recover spontaneously.

Myocardial infarction (MI) is one of the most important causes of mortality in humans1-3. In order to improve morbidity and mortality in patients with MI ...

A Modified Method for Heterotopic Mouse Heart Transplantion

Mice are often used as heart transplant donors and recipients in studies of transplant immunology due to the wide range of transgenic mice and reagents available. A difficulty is presented due to the small size of the animal and the considerable technical challenges of the microsurgery involved in heart transplantation. In particular, a high rate of technical failure early after transplantation may result from recipient death and post-operative complications such as hind limb paralysis or a non-beating heart. Here, the complete technique for heterotopic mouse heart transplantation is demonstrated, involving harvesting the donor heart and its subsequent implantation into a recipient mouse. The donor heart is harvested immediately following in situ perfusion with cold heparinized saline and transection of the ascending aorta and pulmonary artery. The recipient operation involves preparation of the abdominal aorta and inferior vena cava (IVC), followed by end-to-side anastomosis of the donor aorta with the recipient aorta using a single running 10-0 microsuture and a similar anastomosis of the donor pulmonary artery with the recipient IVC. Following the operation the animal is injected with 0.6 ml normal saline subcutaneously and allowed to recover on a 37&#160;&#176;C heating pad. The results from 227 mouse heart transplants are summarized with a success rate at 48 hr of 86.8%. Of the 13.2% failures within 48 hr, 5 (2.2%) experienced hind limb paralysis, 10 (4.4%) had a non-beating heart due to graft ischemic injury and/or thrombosis, while 15 (6.6%) died within 48 hr.

A technique is demonstrated for the microsurgical procedure for heterotopic transplantation of hearts in mice, including simplified methods for donor harvesting and recipient vessel anastomosis.

Mice are often used as heart transplant donors and recipients in studies of transplant immunology due to the wide range of transgenic mice and reagents ...

Designing CAD/CAM Surgical Guides for Maxillary Reconstruction Using an In-house Approach

Computer-aided design/computer-assisted manufacturing (CAD/CAM) is now being evaluated as a preparative technique for maxillofacial surgery. Because this technique is expensive and available in only limited areas of the world, we developed a novel CAD/CAM surgical guide using an in-house approach. By using the CAD software, the maxillary resection area and cutting planes and the fibular cutting planes and angles are determined. Once the resection area is decided, the necessary faces are extracted using a Boolean modifier. These superficial faces are united to fit the surface of the bones and thickened to stabilize the solids. Not only the cutting guides for the fibula and maxilla but also the location arrangement of the transferred bone segments is defined by thickening the superficial faces. The CAD design is recorded as .stl files and three-dimensionally (3-D) printed as actual surgical guides. To check the accuracy of the guides, model surgery using 3-D-printed facial and fibular models is performed. These methods may be used to assist surgeons where commercial guides are not available.

Methods for designing a computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guide are shown. Cutting planes are separated, united, and thickened to easily visualize the necessary bone transfer. These designs can be three-dimensional printed and checked for accuracy.

Computer-aided design/computer-assisted manufacturing (CAD/CAM) is now being evaluated as a preparative technique for maxillofacial surgery. Because this ...

Porcine As a Training Module for Head and Neck Microvascular Reconstruction

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes have been available for years in many surgical fields. We used the female (because they are easy to handle for the procedure) Yorkshire pigs for the head and neck reconstruction by harvesting the deep inferior epigastric artery perforator or the superior epigastric artery perforator flap. The anastomosis site (neck skin defect or tracheal wall defect) was prepared via the dissection of the common carotid artery and the internal jugular vein, in which 3.5&#215; loupe magnification was used for anastomosis as we use on human cases in real life. This procedure demonstrates a new training method using a reliable learning model and provides a detailed anatomy in a live scenario. We focused on the ischemia time, harvesting, vessel anastomosis, and designing the flap to fit the defect site. This model improves tissue handling and with the use of proper instruments can be repeated many times so that the surgeon is fully confident before starting the surgery on humans.

Here we present a protocol for the use of the pig superior epigastric artery perforator flap as a learning module for head and neck microvascular reconstruction.

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes ...

A Training and Testing System for Performing Vascular Reconstruction In Vitro

Manual vascular reconstruction training is essential for a beginner surgeon. However, an optimal training system for vascular reconstruction in vitro has yet to be developed. In this study, we introduce an in vitro training and testing system using a magnetic anchoring technique with which a trainee can practice manual vascular reconstruction individually. Additionally, this system can also be used to test the quality of the reconstruction. The described system includes a vascular reconstruction training machine, magnetic tractors, and a magnetic suture puller. In this manuscript, we detail an end-to-end vein anastomosis using porcine right and left iliac veins. To identify the potential damage caused by a magnetic suture puller on the suture, we created three groups with six segments of 4-0 polypropylene sutures each: a control group with no intervention on the polypropylene suture, a group in which the polypropylene suture is manually pulled with sterile gloves 20x, and a magnetic puller group in which the magnetic puller pulled the polypropylene suture 20x. These groups were tested by light microscopy and breaking strength tests, and the effect of reconstruction was assessed. In the light microscopy test, the control group was less likely to be damaged (p &#60; 0.05) and the number of damaged points of the manual group and magnetic puller group were similar (p &#62; 0.05). The results of the breaking strength test were compared across groups and no significant difference was observed (p &#62; 0.05). The end-to-end anastomosis of the porcine iliac veins was successfully performed using this training system, and the reconstructed veins could undergo 2.0 kPa perfusion pressure. Using this training and testing system the trainee can practice manual vascular reconstruction in vitro individually with the aid of magnetic tractors and a magnetic suture puller, and the quality of the reconstruction can be tested.

Here we present a training and testing system where a trainee can complete manual vascular reconstruction in vitro individually using a magnetic anchoring technique. The system can also be used to test the quality of reconstruction.

Manual vascular reconstruction training is essential for a beginner surgeon. However, an optimal training system for vascular reconstruction in vitro has ...

Technical Detail for Robot Assisted Pancreaticoduodenectomy

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic platform, including three-dimensional vision, wristed instruments, and improved ergonomics, allow the surgeon to recapitulate the principles of open pancreatoduodenectomy allowing safe oncologic dissection, hemostasis, and meticulous reconstruction. Over the course of the past decade, significant strides have been achieved in outlining the safety, feasibility, and learning curve of the robotic Whipple. When performed by high volume pancreatic surgeons experienced in RPD, recent comparative effectiveness studies show potential advantages compared to the open technique, including reductions in hospital stay and morbidity. National data also show reductions in conversion rates compared to its laparoscopic counterpart. Although long-term oncologic data are still needed, short-term oncologic surrogates of margin resection and lymph node harvest suggest no compromise in oncologic outcomes. As pancreatic surgeons increasingly integrate robotics into their practice, proficiency-based training and credentialing will be necessary for the safe application and dissemination of RPD. Here, we provide the detailed steps of a robotic pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.&#160;

The following manuscript details a stepwise approach to the robot-assisted pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic ...

A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible

Valid comparisons of postoperative accuracy results in computer-assisted reconstruction of the mandible are difficult due to heterogeneity in imaging modalities, mandibular defect classification, and evaluation methodologies between studies. This guideline uses a step-by-step approach guiding the process of imaging, classification of mandibular defects and volume assessment of three-dimensional (3D) models, after which a legitimized quantitative accuracy evaluation method can be performed between the postoperative clinical situation and the preoperative virtual plan. The condyles and the vertical and horizontal corners of the mandible are used as bony landmarks to define virtual lines in the computer-assisted surgery (CAS) software. Between these lines the axial, coronal, and both sagittal mandibular angles are calculated on both pre- and postoperative 3D models of the (neo)mandible and subsequently the deviations are calculated. By superimposing the postoperative 3D model to the preoperative virtually planned 3D model, which is fixed to the XYZ axis, the deviation between pre- and postoperative virtually planned dental implant positions can be calculated. This protocol continues and specifies an earlier publication of this evaluation guideline.

Here, we propose a practical, feasible and reproducible evaluation guideline for computer-assisted reconstruction of the mandible in order to create uniformity between studies regarding postoperative accuracy evaluation. This protocol continues and specifies an earlier publication of this evaluation guideline.

Valid comparisons of postoperative accuracy results in computer-assisted reconstruction of the mandible are difficult due to heterogeneity in imaging ...

Therapy Interventions for Upper Limb Amputees Undergoing Selective Nerve Transfers

Targeted Muscle Reinnervation (TMR) improves the biological control interface for myoelectric prostheses after above-elbow amputation. Selective activation of muscle units is made possible by surgically re-routing nerves, yielding a high number of independent myoelectric control signals. However, this intervention requires careful patient selection and specific rehabilitation therapy. Here a rehabilitation protocol is presented for high-level upper limb amputees undergoing TMR, based on an expert Delphi study. Interventions before surgery include detailed patient assessment and general measures for pain control, muscle endurance and strength, balance, and range of motion of the remaining joints. After surgery, additional therapeutic interventions focus on edema control and scar treatment and the selective activation of cortical areas responsible for upper limb control. Following successful&#160;reinnervation of target muscles, surface electromyographic (sEMG) biofeedback is used to train the activation of the novel muscular units. Later on, a table-top prosthesis may provide the first experience of prosthetic control. After fitting the actual prosthesis, training includes repetitive drills without objects, object manipulation, and finally, activities of daily living. Ultimately, regular patient appointments and functional assessments allow tracking prosthetic function and enabling early interventions if malfunctioning.

This work presents a protocol to enhance prosthetic function after selective nerve transfer surgery. Rehabilitation interventions include patient information and selection, support of wound healing, cortical re-activation of sensory-motor areas of the upper limb, training of selective muscle activation, prosthetic handling in daily life, and regular follow-up assessments.

Targeted Muscle Reinnervation (TMR) improves the biological control interface for myoelectric prostheses after above-elbow amputation. Selective ...

A Modified Technique for Arteriovenous Fistula Construction in Rabbits

Juxta-anastomotic stenosis is a challenging problem that often causes non-maturation and decreases the patency of an arteriovenous fistula (AVF). Injury to the veins and arteries during the operation and hemodynamic changes can lead to intimal hyperplasia, leading to juxta-anastomotic stenosis. To reduce injury to the veins and arteries during the operation, this study proposes a new modified no-touch technique (MNTT) for AVF construction that can decrease the rate of juxta-anastomotic stenosis and improve the AVF patency. To unravel the hemodynamic changes and mechanisms of the MNTT, this study presented an AVF procedure using this technique. Although this procedure is technically challenging, 94.4% procedural success was achieved after adequate training. Ultimately, 13 out of 34 rabbits had a functional AVF 4 weeks after the surgery, leading to a 38.2% AVF patency rate. However, at 4 weeks, the survival rate was 86.1%. Ultrasonography showed active blood flow through AVF anastomosis. Furthermore, the spiral laminar flow was observed in the vein and artery near the anastomosis, suggesting that this technique may improve the hemodynamics of the AVF. On histological observation, significant venous intimal hyperplasia was observed at the AVF anastomosis, whereas no significant intimal hyperplasia was observed at the proximal external jugular vein (EJV) of the anastomosis. This technique will improve the understanding of the mechanisms underlying the use of MNTT for AVF construction and provide technical support for the further optimization of the surgical approach in AVF construction.

The present protocol proposes the creation of an arteriovenous fistula in rabbits using a modified no-touch technique. The technique involves the side-to-side anastomosis of the common carotid artery and external jugular vein without the dissection of the perivenous tissues or cutting off the artery.

Juxta-anastomotic stenosis is a challenging problem that often causes non-maturation and decreases the patency of an arteriovenous fistula (AVF). Injury ...

Management of the Uncinate Process in No-Touch Laparoscopic Pancreaticoduodenectomy

Laparoscopic pancreatoduodenectomy (LPD) is a demanding abdominal operation that necessitates meticulous surgical skills and teamwork. The management of the pancreatic uncinate process is one of the most important and difficult processes in LPD because of its deep anatomical location and difficult exposure. Complete resection of the uncinate process and mesopancreas has become the cornerstone of LPD. In particular, it is even more difficult to avoid positive surgical margins and incomplete lymph node dissection when the tumor is located in the uncinate process. No-touch LPD, which is an ideal oncological operation process fitting the "tumor-free" principle, has been reported by our group previously. This article introduces the management of the uncinate process in no-touch LPD. Based on the multi-angle arterial approach, in this protocol, the median-anterior and left-posterior approaches to the SMA are used to correctly deal with the important vascular structure, the inferior pancreaticoduodenal artery (IPDA), in order to ensure the safe and complete excision of the uncinate process and mesopancreas. For the achievement of the no-touch isolation technique in LPD, the pancreatic head and the blood supply to the duodenal region must be severed at the very early stage of the operation; after that, the tumor can be isolated intact, resection can be performed in situ, and finally, the tissue can be removed en bloc. This paper aims to show the distinctive ways to manage the uncinate process in no-touch LPD and investigate the viability and safety of this approach. Moreover, the technique may increase the R0 resection rate.

Complete resection of the uncinate process and mesopancreas is one of the most important and difficult processes in laparoscopic pancreatoduodenectomy (LPD). This article presents a method for managing the uncinate process in no-touch LPD using the median-anterior and left-posterior approaches to the superior mesenteric artery (SMA).

Laparoscopic pancreatoduodenectomy (LPD) is a demanding abdominal operation that necessitates meticulous surgical skills and teamwork. The management of ...