Laparoscopic Splenectomy Is a Safe Method in Cases of Extremely Large Spleens

Abstract

Introduction:

The aim of this study was to assess if there is a relationship between the outcome of laparoscopic splenectomy (LS) procedures and the size of the spleen, the learning curve, or the method of specimen retrieval.

Patients and Methods:

Between January 1, 2002 and December 31, 2013, 70 LS procedures were performed at our department. Based on the weight of the removed spleen, patients were divided into three groups: Group 1, <350 g (n=32); Group 2, 350–1000 g (n=15); and Group 3, >1000 g (n=7). The role of the learning curve was also analyzed with the first 20 surgeries considered as the learning period. The specimen was retrieved with morcellation through the lateral port site in 54 cases, whereas in 11 cases, the large spleen was retrieved through a Pfannenstiel incision.

Results:

The mean duration of surgery was 122 minutes. When considered by spleen weight, durations for Groups 1–3 were 117, 128, and 134 minutes, respectively. When considered by the learning curve, durations for learning and later periods were 149 and 111 minutes, respectively (P=.002). After the learning period, larger spleens were removed (208 versus 519 g; P=.02), and there were fewer conversions. The mean postoperative hospital stay was 5.1 days. In the 11 cases where the specimen was retrieved through a Pfannenstiel incision, the mean duration of surgery was 108 minutes, and the mean spleen weight was 1032 g.

Conclusions:

Our study supports that the proposal that LS is safe and has numerous advantages, even in the case of massive splenomegaly. Our results were mainly affected by the spleen size and the learning curve.

Introduction

Since its introduction in 1991,¹ laparoscopic splenectomy (LS) has been considered the gold standard in spleen surgery, and the advantages of this technique over open surgery are indisputable.^2,3 The safety of the method has also been shown in spleens of extreme size.⁴ As the laparoscopic procedure has become widely used in case of extreme-sized spleens as well, the difficulty of retrieving specimens sometimes weighing more than 2000 g has been encountered. The usual practice is to place the specimen in an Endobag™ (Covidien, Mansfield, MA) and retrieve it through one of the port sites with morcellation. In the case of hand-assisted LS (HALS), it is obvious to retrieve the specimen through the hand port site. Besides these procedures, the retrieval of the specimen through a Pfannenstiel incision is also known.⁵

At our department, we also retrieve spleens of extreme size from the abdominal cavity through a Pfannenstiel incision during LS, when it is technically difficult to place the specimen in an Endobag and perform morcellation within the abdominal cavity. This article presents our experience with the laparoscopic removal of extreme-sized spleens, highlighting the effects of spleen size and the specimen retrieval method (through Pfannenstiel incision versus morcellation through a port site) on the results. Based on literature data, besides spleen size, it is the learning curve that has a crucial effect on splenectomy results,^6,7 which was also investigated.

Patients and Methods

Between January 1, 2002 and December 31, 2013, 70 LS procedures were performed at the Department of Surgery, University of Szeged, Szeged, Hungary. The male-to-female ratio of the 70 patients was 19:51, and the mean age was 42.6 years (range, 14–74 years). Preoperative assessment (ultrasound, computed tomography scan) and Pneumovax^® (Merck, Kenilworth, NJ) vaccination were performed in each case. The surgical interventions were performed with antibiotic protection and a close monitoring of platelet count.

The surgical interventions were performed with the patient in a 30° lateral decubitus position with the “anterolateral, hanging spleen” technique according to Delaitre et al.¹ For the control of the vessels in the splenic hilum, the Endo GIA™ stapler (Covidien) was used in the learning period until 2006, and then individual vessel dissection and Hem-o-lok^® (Weck^®, Teleflex Medical, Research Triangle Park, NC) clip ligation as described by Tan et al.⁸ were used. The dissection of the hilum, similarly to the method of Tan et al.,⁸ was performed from the anterior to posterior and from the inferior to superior direction, which makes the identification of the vessels and the pancreas easy and with which the risk of pancreatic injury can be minimized. The specimen was usually retrieved after placing it in an Endobag through the lateral port site with morcellation or, after 2009 in 11 cases of extreme-sized spleen, through a Pfannenstiel incision. At the end of each surgery, a drain was left in place, which was removed on the second postoperative day.

In our study, we evaluated the indications for surgery, the duration of surgery, the conversion rate, the re-operation rate, the time to bowel function recovery, the length of hospital stay, and the weight of the removed specimens. The results obtained were analyzed according to four aspects. First, the role of the learning period was investigated. The learning curve, in accordance with literature data, was defined as 20 surgeries.^6,7 The effect of using a stapler versus clips for controlling the vessels in the hilum on our results was evaluated. Furthermore, the role of spleen size was assessed dividing the patients into three groups based on the spleen weight determined during histological examination of the specimen: Group 1 consisted of patients with a spleen weight of less than 350 g, Group 2 included those with a spleen weight between 350 and 1000 g, and Group 3 comprised those with a spleen weighing more than 1000 g. Finally, the role of the specimen retrieval method (Endobag+morcellation versus Pfannenstiel incision) was investigated.

Statistics

For the comparison of the mean values, t test and one-way analysis of variance were used, as well as the Mann–Whitney test. The normal distribution of samples was tested using the Kolmogorov–Smirnov test. Categorical data were analyzed using chi-squared and Fisher's exact tests. SPSS version version 15.0 software (© 2007; SPSS Inc., Chicago, IL) was used for statistical analysis.

Results

The indication for surgery, as with literature data, was idiopathic thrombocytopenic purpura in more than 50% of the cases (in 37 cases). Furthermore, the surgery was performed because of congenital spherocytosis in 11 cases (15.7%), lymphoma in 11 cases (15.7%), autoimmune hemolytic anemia in 4 cases (5.7%), and splenic cyst in 2 cases (2.9%). Surgery was indicated because of melanoma metastasis, sarcoidosis, chronic renal failure, hemosiderosis, and malignant mast cell tumor in 1 case each (1.4%) (Table 1).

Table 1.

Indications for Surgery in This Study

Indication	Number (%)
ITP	37 (52.9%)
Congenital spherocytosis	11 (15.7%)
Non-Hodgkin's lymphoma	7 (10%)
Hodgkin's lymphoma	4 (5.7%)
AIHA	4 (5.7%)
Cyst	2 (2.9%)
Other	5 (7.1%)

Data from the University of Szeged were summarized through 2013 (n=70).

AIHA, autoimmune hemolytic anemia; ITP, idiopathic thrombocytopenic purpura.

Based on the histological results, the mean weight of the spleens removed laparoscopically was 450±1945 g. Spleens considered to be of normal size (<350 g) were removed in 42 cases (Group 1), spleens weighing between 350 and 1000 g in 19 cases (Group 2), and spleens weighing over 1000 g in 9 cases (Group 3). The importance of experience is demonstrated by the fact that whereas the mean weight of the spleens removed during the first 20 surgeries, defined in the literature as the learning curve, was 208 g, it was 519 g afterward (P=.02). We removed the first spleen weighing more than 1000 g laparoscopically in 2008.

The mean duration of surgery was 122±154 minutes, with a mean duration by spleen size of 117 minutes in Group 1, 128 minutes in Group 2, and 134 minutes in Group 3. The mean duration of surgery during the learning curve was 149 minutes, followed by a mean duration of 111 minutes, which is a significant reduction (P=.002) (Table 2).

Table 2.

Laparoscopic Splenectomy Results by Learning Curve

	Learning curve (n=20)	After the learning curve (n=50)	P value
Duration of surgery (minutes)	149±95	111±65	.002^a
Stapler versus clip	15 versus 5	1 versus 49	–
Conversion	3 (15%)	2 (4%)	.125
Re-operation	1 (5%)	1 (2%)	.795
Hospital stay (days)	6.15±5	4.7±4	.013^a
Time to bowel function recovery (days)	2.5±3	2.59±2	.674
Pfannenstiel incision	0	11 (22 %)	—
Specimen weight (g)	208±256	519±717	.02^a

Data are mean±standard deviation values or number of patients (%) as indicated.

P<.05 was defined as a significant difference.

Between January 2002 and December 2005, we used a vascular stapler (n=15) for the control of the vessels in the splenic hilum. After that, the more cost-effective Hem-o-lok clips were used (n=54), except for 1 case when the hilum was controlled with an Endo GIA because of the rupture of the splenic vein. The mean duration of surgeries with the use of a stapler was 151±105 minutes, whereas that of the surgeries with the use of clips was 114±124 minutes, which is a significant reduction in duration (P=.002).

Conversion was performed in 5 cases (7.1%), with the majority in the learning curve period (3 cases between 2002 and 2004). In these cases the mean weight of the spleen was 463±945 g, and the hospital stay was prolonged and reached 7.8 days.

Three intraoperative complications that could be resolved laparoscopically are worth mentioning. In 1 case, the already mentioned rupture of the splenic vein was treated with an Endo GIA stapler; 1 case of rupture of the left lobe of the liver and 1 case of diaphragmatic injury during the mobilization of the superior pole could be handled with laparoscopic sutures.

Re-operation was required in 2 cases (2.9%) because of bleeding. The weight of the spleen was below average (138 and 403 g) in these cases.

Additional perioperative morbidities occurred in 3 cases (pneumothorax on the first postoperative day and, in 2 patients, recurrent fever after the surgery). There were no cases of postoperative pancreatitis or perioperative mortality.

The mean time to bowel function recovery was 2 (2.57±1.1) days, which showed a nonsignificant relationship with the weight of the spleen: Group 1, 2.5 days; Group 2, 2.9 days; and Group 3, 3.3 days. A correlation was also found in regard to the length of hospital stay: it was 5.1±4.8 days on average (5, 5.2, and 5.4 days for Groups 1–3, respectively). The length of hospital stay was significantly reduced after the learning curve (6.15 versus 4.7 days; P=.013) (Table 3).

Table 3.

Laparoscopic Splenectomy Results by Weight of the Specimen

	Group 1 (<350 g) (n=42)	Group 2 (350–1000 g) (n=19)	Group 3 (>1000 g) (n=9)	P value^a	P value^b
Duration of surgery (minutes)	117±67	128±74	134±59	.258	.374
Conversion	3 (7.1%)	1 (5.3%)	1 (11.1%)	.479	.258
Reoperation	1 (2.4%)	1 (5.3%)	0	.145	.489
Hospital stay (days)	5±4	5.2±5	5.4±4	.846	.661
Time to bowel function recovery (days)	2.5±3	2.9±2	3.3±3	.452	.207
Pfannenstiel incision	2 (4.7%)	4 (21%)	5 (55.6%)	.845	.274
Specimen weight (g)	160±159	578±575	1494±1220	—	—

Data are mean±standard deviation values or number of patients (%) as indicated.

P value for comparison between Group 1 and Group 2.

P value for comparison between Group 1 and Group 3.

As mentioned previously, the retrieval of extremely large spleens was performed through an 8–10-cm Pfannenstiel incision without morcellation in 11 cases after 2009. The introduction of this procedure was required because placing the enormous spleens removed during the LS (weighing 1000–2000 g, based on histological findings) in a bag intraabdominally and retrieving them with morcellation would have been technically difficult and time consuming because of the extreme size. Because of the risk of splenosis, we do not perform morcellation without placing the specimen in a bag.

In these cases, the mean weight of the spleen was 1032±534 g, with a weight over 2000 g in 2 cases. The mean duration of surgery was 108±62 minutes, the mean time to bowel function recovery was 3.2±2 days, and the mean length of hospital stay was 4.7±3 days. Based on the above data, the results of the cases with retrieval through a Pfannenstiel incision are not worse than those of the purely laparoscopic group; on the contrary, these interventions resulted in a shorter duration of surgery (108 versus 125 minutes; P=.05) and hospital stay (4.7 versus 5.2 days; P=.178), although the time to bowel function recovery was reasonably (lower abdominal laparotomy) longer (3.2 versus 2.5 days; P=.394). Additional factors are that better histological assessment can be performed on the intact specimen and that the Pfannenstiel incision is considered to be an acceptable cosmetic alternative (as opposed to the left subcostal or upper midline laparotomy) (Table 4).

Table 4.

Laparoscopic Splenectomy Results by Pfannenstiel Incision

	With Pfannenstiel incision (n=7)	Without Pfannenstiel incision (n=47)	P value
Duration of surgery (minutes)	108±62	125±73	.05^a
Hospital stay (days)	4.7±3	5.2±4	.178
Time to bowel function recovery (days)	3.2±2	2.5±3	.394
Specimen weight (g)	1032±534	338±245	.0001^a

Data are mean±standard deviation values.

P<.05 indicates a significant difference.

Discussion

Since its introduction, LS has become the gold standard because of its numerous known advantages over open surgery. Several systematic reviews have confirmed the advantages of the method over the open technique (e.g., the meta-analyses of Winslow and Brunt² and Bai et al.,³ which show uniformly lower complication rate, shorter hospital stay, reduced blood loss, and longer duration of surgery in a population of about 3000 patients. The publications related to the topic uniformly consider it a standardized, safe method in the case of a normal-sized spleen. In the case of massive splenomegaly, however, the opinion is divided. Targorana et al.⁹ have found correlation between spleen weight and conversion rate: compared with the mean rate of 6.7%, a conversion rate of 25% was observed in case of massive splenomegaly. With a conversion rate of 13.3%, Sapucahy et al.¹⁰ have recommend the laparoscopic procedure for smaller spleens. Poulin and Thibault¹¹ did not recommend the laparoscopic method over a craniocaudal diameter of 20 cm and a weight over 1000 g. The article already mentioned by Bai et al.,³ summarizing 39 trials and 1540 patients subjected to LS, defined massive splenomegaly as a spleen weight over 1 kg and found longer duration of surgery, higher conversion rate, higher blood loss, longer hospital stay, and an increased rate of perioperative complications, each of which is considered to be preventable in case of an experienced surgeon. Furthermore, several recent publications have supported that LS is a safer and more effective method than open surgery also in the case of massive splenomegaly.^12–14 These results were also supported by a systematic review performed on 1500 patients in 2012.⁴

In our study, the large spleen had no effect on the conversion rate, and, although there was a trend of increase in duration of surgery and hospital stay in the case of larger spleens, there was no significant difference between the groups.

Several authors have found that the difficulties related to larger spleen size can be resolved with the use of HALS. In an article published in 2007, Wang et al.¹⁵ observed shorter duration of surgery, lower blood loss, and a reduced conversion rate in case of HALS compared with conventional LS. Similar results were presented in the case of complicated splenectomies (supramassive splenomegaly, portal hypertension) as well in their article published in 2013.¹⁶ According to Targorana et al.,¹⁷ the hand-assisted technique decreased the length of hospital stay (4 versus 6.3 days), morbidity was lower (10% versus 36%), and the duration of surgery was shorter (135 minutes versus 177 minutes) in the case of a spleen weighing more than 700 g. When studying the complications of laparoscopic splenectomy, Wang et al.¹⁸ observed a lower postoperative complication rate in case of HALS (in the subxiphoid position) compared with the purely laparoscopic group (odds ratio=22.311 versus 6.713).¹⁸

Retrieving a large-sized spleen from the abdominal cavity may also be difficult during LS. In general, placing the specimen in a retrieval bag and intraabdominal morcellation are recommended. At the end of the procedure, a thorough rinsing of the abdominal cavity with saline is recommended to avoid splenosis, and a color Doppler scan is to be performed within 3 months.^14,19 If the specimen could not be placed in a bag because of its extreme size, our work group retrieved it in whole through a Pfannenstiel incision. Because of the risk of splenosis, we performed intraabdominal morcellation only after placing the specimen in an Endobag.

The Pfannenstiel incision is a known adjunct to several types of laparoscopic surgery. There have been relatively few articles published on its role in laparoscopic surgery of the spleen and the retrieval of the specimen, and those identify the Pfannenstiel incision rather than the site for insertion of the hand port.^20,21 We suppose that a hand port introduced through a Pfannenstiel incision for left upper abdominal surgery leads to unnecessary inconveniences, especially in the case of a right-handed surgeon. Besides, eliminating the use of the hand port reduced the costs during our study.

There is only one publication, the article of Patle et al.,⁵ on making a Pfannenstiel incision for the sole purpose of retrieving the specimen after purely LS, which includes 50 patients operated because of β-thalassemia; the specimen was retrieved through a 7–8-cm Pfannenstiel incision in 37 cases and with the extension of the umbilical port site in 12 cases, and conversion was performed in 1 case. In the case of retrieval through the Pfannenstiel incision, similar to our results, a significantly shorter duration of surgery was observed, and the procedure is considered a cosmetically acceptable alternative.

In the case of massive splenomegaly, the main complication is severe bleeding, which is also the main cause of conversions and re-operations. Different sources estimate the conversion rate to be in the range of 6%–36%.^22–25 In our study, it was 7.1%, and conversions were performed mainly in the learning curve period. According to literature data, ascending thromboembolism is a more common complication of laparoscopic surgeries than portal/deep venous thrombosis or pulmonary embolism^26–28; however, we did not encounter this complication in our research.

Besides the size of the spleen, the most important factor in our study was the experience of the team. Several publications in the literature are about this topic. Cusick and Waldhausen⁶ investigated the importance of the learning curve after 49 cases of splenectomy in children; they found significant reduction in the duration of surgery, intraoperative blood loss, and hospital costs when comparing the results of the first and last 10 patients and established the limit after which the duration of surgery and the costs are reduced owing to the experience in 20 surgeries. Peters et al.⁷ have defined the learning curve studying surgeries performed because of idiopathic thrombocytopenic purpura. After sorting 50 surgeries into groups of 10 in chronological order, they concluded that the duration of surgery of patients in the first two groups was significantly longer than that in Groups 3–5. No difference was found in blood loss, hospital stay, and time to oral feeding, and the learning curve was defined as performing at least 20 surgeries.⁷ In our study, the duration of surgery and the length of hospital stay significantly decreased after the learning curve.

For the control of the vessels in the splenic hilum, we initially used a vascular stapler, and after 2006, we used individual vessel dissection and clips, similarly to the method described by Tan et al.⁸ in their article published in 2013. Like these researchers, we found the method to be safe, especially in the case of splenomegaly, when the positioning of the stapler would be difficult because of the reduced space. There are articles about managing the splenic hilum with a LigaSure™ (Covidien) instrument or a Harmonic^® scalpel (Ethicon Endo-Surgery, Blue Ash, OH) only,^29,30 but this method was not used by our work group.

Conclusions

Based on our results, similar to literature data, it may be established that LS can be considered a surgical procedure with low morbidity after gaining the necessary experience. The most important factors of the successful procedure are possibly the experience of the team and the size of the spleen. In the case of massive splenomegaly, the Pfannenstiel incision may be a cosmetically more acceptable alternative for the retrieval of the spleen than the mini-laparotomy performed for the hand port inserted in the upper abdominal region during HALS, and surgical costs may also be reduced by restricting the use of the hand port. In addition to the above, a shorter duration of surgery, prevention of splenosis, and an improved histological assessment of the specimen might be expected from the use of the Pfannenstiel incision.

Footnotes

Disclosure Statement

No competing financial interests exist.

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