Laparoscopic Splenectomy Alone for Sickle Cell Disease Account of 50 paediatric cases

OBJECTIVES
In Oman, the most frequent indication for a splenectomy in children is sickle cell disease (SCD), which is one of the most common haematological disorders in the Gulf region. This study aimed to describe paediatric laparoscopic splenectomies alone for SCD at a tertiary hospital in Oman.


METHODS
This study was conducted between February 2010 and October 2015 at the Sultan Qaboos University Hospital, Muscat, Oman. The medical records of all children aged ≤15 years old undergoing splenectomies during the study period were reviewed.


RESULTS
A total of 71 children underwent laparoscopic splenectomies during the study period; of these, 50 children (28 male and 22 female) underwent laparoscopic splenectomies alone for SCD. The children's weight ranged between 11-43 kg. The most common indication for a splenectomy was a recurrent splenic sequestration crisis (92%). Surgically removed spleens weighed between 155-1,200 g and measured between 9-22 cm. Operative times ranged between 66-204 minutes and intraoperative blood loss ranged between 10-800 mL. One patient required conversion to an open splenectomy. Postoperative complications were noted in only four patients. The median hospital stay duration was three days.


CONCLUSION
Among this cohort, the mean operating time was comparable to that reported in the international literature. In addition, rates of conversion and postoperative complications were very low. These findings indicate that a laparoscopic splenectomy alone in paediatric patients with SCD is a feasible option.


H
aematological indications for a splenectomy vary globally.2][3][4] In Oman, the most common indication for a splenectomy in children is sickle cell disease (SCD). 5][8] The management of paediatric patients with SCD can be challenging, as surgical procedures may precipitate a sickling crisis. 9Paediatric SCD patients may require a splenectomy for various indications, such as recurrent splenic sequestration or splenic dysfunction. 10The effectiveness of splenectomies in improving haematological outcomes is well-established. 11,12However, most studies in the medical literature combine the results of laparo-scopic splenectomies carried out for various indications such as hereditary spherocytosis, idiopathic thrombocytopaenic purpura or chronic myelomonocytic leukaemia, with only a small number focusing solely on laparoscopic splenectomies among patients with SCD. 1,3,4Moreover, some researchers include children who undergo a combined laparoscopic cholecystectomy and splenectomy. 3Hence, there is a lack of research describing the results of laparoscopic splenectomies alone among children with SCD.
This study aimed to describe the results of laparoscopic splenectomies alone among a cohort of children with SCD.To the best of the authors' knowledge, this is the first study of its kind to analyse laparoscopic splenectomies due to SCD alone, excluding splenectomies performed as a result of other haematological disorders or combined with other surgical procedures.

Methods
This retrospective study was conducted at the Sultan Qaboos University Hospital (SQUH), Muscat, Oman.A review of all patients ≤15 years old undergoing a laparoscopic splenectomy alone for SCD between February 2010 and October 2015 was undertaken.Patients who were operated upon for other haematological diseases or who underwent splenectomies combined with other procedures (e.g. a cholecystectomy) were excluded.The study was retrospective for the first three years of data collection but was then maintained prospectively.
The medical records of the patients were reviewed for the following information: demographic characteristics; indications for the splenectomy; operative time; preoperative and postoperative transfusion requirements; intraoperative complications or blood loss; the need for conversion to open surgery; postoperative complications (including acute chest syndrome [ACS], vaso-occlusive crises and general/ wound infections); administration of narcotic analgaesia; and length of hospital stay.ACS was diagnosed according to previously described criteria. 9ndications for splenectomies alone in children with SCD included either hypersplenism or acute splenic sequestration.Hypersplenism was defined as splenic enlargement with one of the following conditions: anaemia (requiring a transfusion of packed red blood cells exceeding 250 mL/kg per year); thrombocytopaenia (indicated by a platelet count of ≤100,000/mm 3 ); and neutropaenia (indicated by a white blood cell count of ≤4,000/mm 3 ). 13Children were considered to have acute splenic sequestration if they suffered from at least one major or two minor attacks.Major attacks were characterised by a combination of splenic enlargement, a 2-3 g/dL drop in haemoglobin (Hb) levels and associated hypovolemia while minor attacks constituted splenic enlargement and a drop in Hb levels only, without hypovolemia. 12aparoscopic splenectomies were performed according to the following procedure.Preoperatively, all patients received a pneumococcal polyvalent vaccine at least two weeks before the surgery.In addition, ultrasonography scans were performed to determine the size of the spleen and to rule out the presence of concomitant gallstones.Patients were transfused preoperatively if their Hb levels were <10 g/dL.In the operating theatre, patients were placed in a semi-decubitus position with their left side elevated. 3,5,14A total of 25 mg/kg of cefuroxime was administered as an induction dose.The positioning of the ports during the splenectomy is shown in Figure 1.Maryland forceps to 12 patients (24%).There were seven cases of postoperative complications occurring in four patients, including ACS (n = 4; 8%), general infections (n = 2; 4%) and acute pancreatitis (n = 1; 2%).[Table 2].The patient with acute pancreatitis had received an injury to the tail of the pancreas and was diagnosed on the 10 th postoperative day when high amylase levels were noted in the drained fluid.The same patient also developed ACS and remained in the hospital for 55 days.Septic episodes were noted in two patients (4%) and the blood culture of one patient tested positive for Salmonella.These patients required intravenous antibiotics (90 mg/kg of intravenous piperacillin/ tazobactam every 8 hours) for an average of 12 days.
(Olympus Medical Systems, Tokyo, Japan) were used to isolate the splenic vessels where needed while a harmonic scalpel (HARMONIC ® Shears, Ethicon Endo-Surgery Inc., Blue Ash, Ohio, USA) was used to control the hilar vessels and divide the ligaments supporting the spleen.All patients underwent total splenectomies as there is currently a lack of evidence regarding the benefits of partial splenectomies in improving SCD haematological parameters; moreover, partial splenectomies are associated with greater intraoperative blood loss and higher rates of conversion to open surgery. 14,15Postoperatively, patients were managed by a physician specialising in paediatric haematology.One month after discharge, the patients were followed-up in the paediatric surgery outpatient department.
Ethical approval for this study was received from the Medical Research & Ethics Committee of the College of Medicine & Health Sciences at Sultan Qaboos University (MREC #396).

Results
A total of 71 children underwent laparoscopic splenectomies during the study period.Of these, 18 patients were excluded because they underwent laparoscopic cholecystectomies combined with splenectomies and three patients were excluded because they had haematological disorders other than SCD.As such, a total of 50 paediatric patients (28 male and 22 female) underwent splenectomies alone for SCD.The most common reason splenectomies were performed was due to a recurrent splenic sequestration crisis (92%).Most of the children were ≤5 years old (60%).
Five patients required intraoperative blood transfusions while five patients were transfused postoperatively.Narcotic analgaesia was administered  Only one patient required conversion to open surgery due to intractable intraoperative bleeding requiring both intra-and postoperative transfusions.This patient was kept under observation in the Paediatric Intensive Care Unit for 48 hours.In two other patients, a small incision was made in the lower quadrant to remove the spleen.The mean duration of follow-up with paediatric haematologists was 27.00 ± 21.20 months (range: 1-69 months; median: 18 months).

Discussion
To the best of the authors' knowledge, this singlecentre study is the first of its kind in the region describing the results of laparoscopic splenectomies in paediatric patients with SCD.In the current study, the most common indication for a splenectomy was an acute splenic sequestration crisis; the percentage of children requiring a splenectomy for this indication (92%) is higher than that reported in any other study in the literature to date. 2,13,16,17This may be due to early diagnosis or increased acceptance of a laparoscopic approach among family members or caregivers.However, 60% of the children who underwent laparoscopic splenectomies in the present study were under five years old, which is the most common age for an acute splenic sequestration crisis. 10As sequestration is rare beyond this age, it seems likely that some patients required a splenectomy for some other reason.
Splenectomies can be performed either using an open or laparoscopic technique. 11,12Many researchers have reported that a laparoscopic procedure is the superior choice. 1,12,14][3] Moreover, there is a reduced incidence of ACS following a laparoscopic splenectomy compared to the open procedure; this can be attributed to several factors, including the decreased risk of pulmonary fat embolisms and wound infection and a lower incidence of hypoventilation due to reduced postoperative pain. 11Nevertheless, conversion to an open splenectomy may be needed during a laparoscopic splenectomy due to intractable bleeding, adhesion of the spleen, anatomical variations and difficulties in removing the spleen. 3In the current study, the conversion rate was very low (2%); conversion rates in the literature vary from 0-18%. 3 The dissection of the hilar vessels is an important aspect of a laparoscopic splenectomy; to this end, various dissections tools are available, including linear staplers and clipping and harmonic devices. 1,3,4,14lthough it shortens the operative time, en bloc stapling of the hilum can increase the risk of the patient developing arteriovenous fistulae, injuries to the pancreatic tail and splenic or portal vein thrombosis. 4 In a small study of 17 patients, Vargün et al. established a one-year follow-up as a safe period of time for evaluation following en bloc stapling; however, this procedure has not yet been adopted at SQUH. 4,5 In the current study, the splenic hila were handled with Maryland forceps (Olympus Medical Systems) for isolation and an ultrasonic harmonic scalpel was used to seal and divide the vessels.0][21] In the current study, the mean operative time was 119 minutes.This is comparable to times reported in the international literature which record a mean operative time of 107 minutes for en bloc stapling, 130 minutes using the LigaSure ™ Vessel Sealing System (Medtronic, Minneapolis, Minnesota, USA) and 150 minutes for individual ligation. 4,19,20owever, it is important to note that the mean operative time decreases over the years as surgeons become more experienced. 5,21mong postoperative complications, ACS is the most disease-specific in that the complication is caused by the underlying SCD rather than the procedure.In a recent retrospective study, Bonnard et al. reported the incidence of ACS following a laparoscopic splenectomy to be 23%. 9In the present study, the incidence of ACS was much lower (8%).Other serious postoperative complications include pancreatitis due to an injury to the tail of the pancreas during a laparoscopic splenectomy, with a reported incidence of up to 15%. 4 In the current study, only one patient (2%) received an injury to the tail of the pancreas.Moreover, none of the patients developed wound infections, overwhelming post-splenectomy infections (OPSIs), portal or splenic vein thrombosis or visceral injuries.These findings indicate that a laparoscopic splenectomy alone in paediatric patients with SCD is a safe and feasible surgical approach.
The current study had several limitations.This was a descriptive study and lacked a comparison of laparoscopic and open splenectomy techniques.2,14 Nevertheless, this study presents only the results of laparoscopic surgeries for patients with a single haematological condition; hence, the results should be interpreted carefully.Studies documenting the quality of life of SCD patients and

Figure 1 :
Figure 1: Photograph showing the positioning of ports during a laparoscopic splenectomy alone for sickle cell disease.The child is lying in a semi-decubitus position with the arrow pointing towards the head.Note the placement of the camera port (C), retraction port (R) in the epigastrium and right hand working port (RHWP) in the left iliac fossa.

Table 1 :
Descriptive characteristics of paediatric laparoscopic splenectomies alone for sickle cell disease conducted at the Sultan Qaboos University Hospital, Muscat, Oman (N = 50)

Table 2 :
Frequency of intraoperative and postoperative variables of paediatric laparoscopic splenectomies alone for sickle cell disease conducted at the Sultan Qaboos University Hospital, Muscat, Oman (N = 50) PICU = paediatric intensive care unit.