Original Article

Yonago Acta medica 2016;59:232–236

Usefulness of T-Shaped Gauze for Precise Dissection of Supra-Pancreatic Lymph
Nodes and for Reduced Postoperative Pancreatic Fistula in Patients Undergoing
Laparoscopic Gastrectomy for Gastric Cancer
Tomoyuki Matsunaga, Hiroaki Saito, Yuki Murakami, Hirohiko Kuroda, Yoji Fukumoto and Tomohiro Osaki

Division of Surgical Oncology, Department of Surgery, School of Medicine, Tottori University Faculty of Medicine, Yonago 683-8504,
Japan

ABSTRACT

lymph node dissection but an increased incidence of
postoperative pancreatic fistula (POPF). POPF can cause
life-threatening complications, such as intra-abdominal
hemorrhage, abdominal abscesses, and secondary anastomotic leakage.
During open gastrectomy, the pancreas is pulled byhand to obtain a clear view of the supra-pancreatic area,with gauze often used to minimize injury to the pancreas. During laparoscopic gastrectomy (LG), however, thepancreas is pulled with metal forceps, which may injure
the pancreas, resulting in POPF. Injury to the pancreas
may be avoided by using a technique in which the caudal
gland of the pancreas is gently retracted downward bygauze traction, moving the upper border of the pancreas
forward.¹ This technique has also been used to obtain aclear view of the supra-pancreatic area without injuring
the pancreas during dissection of lymph nodes in thisarea. Use of this technique, however, may cause the assistant’s forceps to deviate from the field of view. Thus,
an inexperienced assistant can injure the pancreas by using a part of the forceps that is not covered by gauze. To
reduce injury to the pancreas during its traction by theassistant, we designed a T-shaped gauze (TSG) for use
in the dissection of supra-pancreatic lymph nodes. This
study was performed to investigate the usefulness of thisTSG during LG.

Background

Supra-pancreatic lymph node dissection
is important in patients undergoing laparoscopic gastrectomy (LG) for gastric cancer. A clear view of the supra-pancreatic area is necessary for precise dissection of
supra-pancreatic lymph nodes without injury to the pancreas. This retrospective study assessed the efficacy ofT-shaped gauze (TSG) in retracting the pancreas during
supra-pancreatic lymph node dissection.
Methods The study cohort consisted of 80 patients
who underwent LG for gastric cancer. Of these, 44 patients underwent pancreatic retraction with TSG (TSG
group) and 36 without TSG (non-TSG group). The efficacy of TSG for pancreatic retraction was evaluated bycomparing all grade and Clavien-Dindo grade ≥ III postoperative pancreatic fistula (POPF) and the total numberof dissected supra-pancreatic lymph nodes in the TSG
and non-TSG groups.
Results The rates of all grade (6.8% vs. 11%) and of
Clavien-Dindo grade ≥ III (2.2% vs. 5.5%) POPF werelower in the TSG than in the non-TSG group. The total
number of supra-pancreatic lymph nodes harvested byDissection 1+ (D1+) lymph node dissection was significantly higher in TSG than in non-TSG patients (P =0.0078).
Conclusion TSG may be useful for safe and efficientperformance of supra-pancreatic lymph node dissection.

MATERIALS AND METHODSPatients

Key words

gastric cancer; laparoscopic gastrectomy;
postoperative pancreatic fistula; T-shaped gauzeThis study enrolled 80 consecutive patients pathologically diagnosed with gastric adenocarcinoma, who underwent LG at Tottori University Hospital from March2012 to February 2014. Their clinicopathologic characteristics were determined according to the JapaneseClassification of Gastric Carcinoma (Table 1).2 Tumors
were staged preoperatively by endoscopy, endoscopic
ultrasonography, upper gastrointestinal X-ray, and computed tomography.
The pancreas in the first 36 patients was retractedusing rounded gauze (Fig. 1a) held by the assistant’s forceps on the left-hand side (non-TSG group). The pancreas in the next 44 patients was retracted using TSG (Fig.

Supra-pancreatic lymph node dissection is one of themost important and demanding procedures in laparoscopic lymph node dissection for gastric cancer.1 A
good view of the supra-pancreatic area is important, as
an insufficient view can result not only in suboptimal
Corresponding author: Hiroaki Saito, MD, PhD
sai10@med.tottori-u.ac.jp
Received 2016 June 22
Accepted 2016 July 20
Abbreviations: D1+, Dissection 1+; D2, Dissection 2; d-AMY, drainamylase; LG, laparoscopic gastrectomy; POD, postoperative day;POPF, postoperative pancreatic fistula; TSG, T-shaped gauze232

Reducing postoperative pancreatic fistulaabFig. 1. Gauze samples used in the (a)non-TSG group and (b) TSG groupto retract pancreas. The arrows show
the ligation of gauze. TSG, T-shaped
gauze.

1b), which was formed by ligation of two points of gauze(arrows) (TSG group).
This study was approved by the Ethics Committeeof Tottori University Faculty of Medicine (approval
number 1606A03).

creatic leakage requiring continuous drainage for ≥ 10days or a spiking fever (> 38 °C) with a peripancreatic
abscess demonstrated by computed tomography. POPF
was graded according to Clavien–Dindo criteria.4
Supra-pancreatic lymph nodes

Definition of POPF

The supra-pancreatic lymph nodes were defined by
the Japanese Classification of Gastric Carcinoma.2 We
compared the number of supra-pancreatic lymph nodes
harvested by Dissection 1+ (D1+) lymph node dissection
and Dissection 2 (D2) lymph node dissection.

Amylase concentrations in blood and fluid obtained
from abdominal drains were determined on postoperative day (POD) 3. The International Study Group on
Pancreatic Fistula has defined POPF as drain output ofany measurable volume of fluid on or after POD3, witha drain amylase (d-AMY) concentration of more than
three times the concentration of serum amylase.³ Additional criteria for POPF included clinically obvious pan-

Statistical analysis

The Mann–Whitney U test and chi-square test were
employed to evaluate differences in continuous and cate233

T. Matsunaga et al.

Patient characteristics are shown in Table 1. There
were no significant differences between the TSG and
non-TSG groups in age, gender, depth of invasion, lymph
node metastasis, operation procedure, and operation
time. Of the patients in the TSG and non-TSG groups,
23% and 17%, respectively, underwent D2 lymph nodedissection, although the difference was not statisticallysignificant. Furthermore, d-AMY concentrations on
POD 3 did not differ significantly in the TSG and nonTSG groups.
The rates of all grade (6.8% vs. 11%; Fig. 3a) and
Clavien-Dindo grade ≥ III (2.2% vs. 5.5%; Fig. 3b)
POPF were lower in the TSG than in the non-TSG
group. Moreover, the total number of supra-pancreatic
lymph nodes harvested by D1+ lymph node dissection
was significantly higher in the TSG group (12.6 ± 0.8)
than in the non-TSG group (9.7 ± 0.6) (P = 0.0078; Fig. 4),
which represent that more precise lymph node dissection
was performed by using TSG. On the other hand, thetotal number of supra-pancreatic lymph nodes harvested
by D2 lymph node dissection was not significantly higher in the TSG group (12.5 ± 5.5) than in the non-TSG
group (13.5 ± 3.3) (P = 0.56).

Table 1. Demographic and clinicopathologic characteristics of patients in the TSG and non-TSG groups
Non-TSG group TSG group P valueAge (years)
67.3 ± 14.1
67.6 ± 13.8 0.99
Gender
1.00
Male (n = 60)
27 (75%)33 (75%)
Female (n = 20)
9 (25%)
11 (25%)Depth of invasion
0.77
T1 (n = 61)
28 (78%)33 (75%)
T2/T3/T4 (n = 19)
8 (22%)
11 (25%)Lymph node dissection
0.50
D1+ (n = 64)
30 (83%)34 (77%)D2 (n = 16)
6 (17%)
10 (23%)Operation
0.42
LDG (n = 58)
24 (67%)34 (78%)LPG (n = 13)
8 (22%)
5 (11%)LTG (n = 9)
4 (11%)
5 (11%)
Operation time (min)360 ± 84
340 ± 83 0.22
D-amylase (POD3)
288 ± 362
253 ± 192 0.7
Results reported as mean ± SD or as number (%). D1+, Dissection
1+; D2, Dissection 2; LDG, laparoscopic distal gastrectomy; LPG,
laparoscopic proximal gastrectomy; LTG, laparoscopic total gastrectomy; POD, postoperative day; T1, tumor has invaded lamina
propria or submucosa; T2, tumor has invaded the muscularis
propria; T3, tumor has penetrated subserosal connective tissue
without invasion of visceral peritoneum or adjacent structures; T4,
tumor has invaded serosa (visceral peritoneum) or adjacent structures; TSG, T-shaped gauze.

DISCUSSION
The number of patients undergoing LG for gastric cancer is increasing rapidly in Japan. Japanese gastric cancer treatment guidelines recommend LG or open distal
gastrectomy for the treatment of clinical stage I gastriccancer.5 The development of less invasive treatment
techniques and recent advances in perioperative management have improved the postoperative mortality rateand incidence of postoperative complications in patients
undergoing gastrectomy. However, POPF remains aserious complication, which may contribute to the development of life-threatening conditions. Careful handlingof the pancreas during surgery may reduce the incidenceof POPF. Supra-pancreatic lymph node dissection usu-

gorical variables, respectively. GraphPad Prism software
version 6.0 (GraphPad Software, La Jolla, CA) was used
for all statistical analyses, with P < 0.05 considered statistically significant.
RESULTS
Figure 2 shows a patient with POPF, resulting from injury to the pancreas caused by the part of the assistant’s
forceps not covered by gauze. This result indicated theimportance of proper retraction of the pancreas during
LG to avoid POPF.

Fig. 2. A representative patient who experienced an injury to the pancreas caused by the surgical assistant’s forceps during supra-pancreatic lymph node dissection (arrow). POPF later developed. POPF, postoperative pancreatic fistula.

234

Matsunaga
et al. Figure 3	
Reducing postoperative pancreatic fistula
a	

b	

(%)	

(%)	

12

6

10

5

8

4

6

3

4

2

2

1

0

Non-TSG group

TSG group

0

Non-TSG group

TSG group

Number of dissected lymph nodes	

Fig. 3. The incidence of POPF.
The rates of (a) all grade and (b) Clavien-Dindo grade ≥ III POPF in the TSG and non-TSG groups. The rates of all grades of POPF in
Matsunaga
et al.
Figureand4	
the rates of grade ≥ III POPF were 2.2% and 5.5%, respectively. POPF, postoperathese two groups
were 6.8% and 11%,
respectively,
tive pancreatic fistula; TSG, T-shaped gauze.

P = 0.0078	

result in pancreatic leakage. To avoid possible injury,
surgical assistants should retract the pancreas gently
and carefully with gauze, paying close attention to thetips of the forceps. However, the assistant’s forceps may
deviate from the field of view when attempting to obtaina magnified view of the supra-pancreatic area during
supra-pancreatic lymph node dissection. Therefore, an
inexperienced assistant can injure the pancreas by using part of the forceps not covered TSG. We found that
this TSG could be easily held by the assistant due to thepresence of a convex part avoiding the gauze gap of theforceps. Furthermore, the parts of the forceps that touch
the surface of pancreas are always covered by gauze.
Indeed, this study showed that use of TSG significantly
reduced the incidence of POPF.
As the most likely source of pancreas-related complications is seepage of pancreatic juice from the surfaceof the pancreas, d-AMY concentration may be useful inthe early diagnosis of pancreas-related complications,8
including POPF.9 However, we found no significant
difference in d-AMY levels between the TSG and nonTSG groups. Obama et al. also reported that although
there was a statistically significant difference in thed-AMY level between the patient groups with and without pancreas-related complications, they did not find avery high predictive value of the d-AMY level alone forpostoperative complications.8 It is likely that the drained
fluid volumes may have altered amylase level. Lymphorrhea following radical lymph node dissection may havediluted the amylase concentration of the drainage fluid,

25
20
15
10
5
0
Non-TSG group	

TSG group	Fig. 4. Numbers of lymph nodes harvested during D1+ lymph
node dissection in the TSG and non-TSG groups. The total number of supra-pancreatic lymph nodes harvested were 12.6 ± 0.8
and 9.7 ± 0.6, respectively, a difference that was statistically significant (P = 0.0078). D1+, Dissection 1+; TSG, T-shaped gauze.

ally involves ultrasonic cutting and coagulating devices.
Because the laparoscope provides a magnified view, thecutting lines for supra-pancreatic lymphadenectomy tend
to be closer to the cranial edge of the pancreas, which
may cause heat injury.6, 7
Retraction of the pancreas is necessary to obtain aclear view of supra-pancreatic lesions and perform precise lymph node dissection, regardless of whether open
gastrectomy or LG is performed. However, retraction of
the pancreas can cause parenchymal injury, which may
235

T. Matsunaga et al.

which may have concealed the leakage of pancreatic
juice. Furthermore, drains in some patients may havecome obstructed or dislocated.
In conclusion, this study showed that TSG may
be useful for the safe and efficient performance of supra-pancreatic lymph node dissection, decreasing theincidence of POPF.

16003309.
4 Dindo D, Demartines N, Clavien PA. Classification of surgicalcomplications: a new proposal with evaluation in a cohort of6336 patients and results of a survey. Ann Surg. 2004;240:20513. PMID: 15273542.
5 Japanese Gastric Cancer Association. Japanese Gastric Cancer Treatment Guidelines 2014. Tokyo: Kanehara; 2014. p. 178. Japanese.
6 Ryu KW, Kim YW, Lee JH, Nam BH, Kook MC, Choi IJ,
et al. Surgical complications and the risk factors of laparoscopy-assisted distal gastrectomy in early gastric cancer. Ann
Surg Oncol. 2008;15:1625-31. PMID: 18340493.
7 Perko Z, Pogorelic Z, Bilan K, Tomic S, Vilovic K, Krnic D,
et al. Lateral thermal damage to rat abdominal wall after
harmonic scalpel application. Surg Endosc. 2006;20:322-4.
PMID:16333532.
8 Obama K, Okabe H, Hosogi H, Tanaka E, Itami A, Sakai Y.
Feasibility of laparoscopic gastrectomy with radical lymph
node dissection for gastric cancer: from a viewpoint of pancreas-related complications. Surgery. 2011;149:15-21. PMID:
20627337.
9 Sano T, Sasako M, Katai H, Maruyama K. Amylase concentration of drainage fluid after total gastrectomy. Br J Surg.
1997;84:1310-2. PMID: 9313722.

The authors declare no conflict of interest.

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