Early and Mid-term Outcomes of Single-Stage Laparoscopic Sleeve Gastrectomy

Transcription

1 OBES SURG (2010) 20: DOI /s z CLINICAL RESEARCH Early and Mid-term Outcomes of Single-Stage Laparoscopic Sleeve Gastrectomy Sanket Srinivasa & Laura S Hill & Tarik Sammour & Andrew G Hill & Richard Babor & Habib Rahman Published online: 4 September 2010 # Springer Science+Business Media, LLC 2010 Abstract Background This is the largest single-centre series of single-stage laparoscopic sleeve gastrectomy (LSG) reporting on perioperative outcomes, weight loss, comorbidity resolution including urological outcomes and results in the super obese. Review of prospectively collected data for patients who underwent LSG from March 2007 August Methods There were 253 patients with a mean age of 44 years (SD, 9) and a mean preoperative body mass index (BMI) of 50 kg/m 2 (SD, 7). There were 17 (7%) major complications and no deaths. The mean follow-up was 9 months. One hundred and seventy-one patients with a mean follow-up of 12 months had a mean postoperative weight loss of 41 kg (SD, 16) and mean excess BMI (mebmi) loss of 59% (SD, 22). Results One hundred fourteen patients were super obese (BMI, >50 kg/m 2 ). The mean weight loss was 45 kg (SD, 18), and the mebmi lost was 49% (SD, 21). Super-obese patients experienced more complications (p=0.02) and lost less ebmi (49% vs. 61%; p<0.01). Fifty-three patients (46%) remained morbidly obese (BMI, >40 kg/m 2 ) postoperatively. Hypertension and diabetes improved or resolved in 73 (79%) and 73 (90%) patients, respectively. Stress urinary incontinence was reported preoperatively in 60 (32%) females, and complete resolution or improvement was reported in 54 (90%) patients. S. Srinivasa (*) : L. S. Hill : T. Sammour : A. G. Hill : R. Babor : H. Rahman Department of Surgery, South Auckland Clinical School, Middlemore Hospital, University of Auckland, Auckland, New Zealand sanketsri@gmail.com Conclusions LSG provides satisfactory weight loss and resolution of comorbidities in the short- and medium-term with inferior, though acceptable, results in the super obese. Keywords Bariatric surgery. Gastrectomy. Obesity. Laparoscopic surgery Introduction Laparoscopic sleeve gastrectomy (LSG) is being increasingly favoured as a stand-alone bariatric procedure internationally, despite being considered investigational [1, 2]. A steadily accumulating body of evidence has indicated that LSG provides satisfactory weight loss as a stand-alone procedure with minimal morbidity and mortality [1]. The resultant weight loss has been ascribed to decreased stomach size and due to resection of the gastric fundus, which decreases plasma ghrelin and causes early satiety and suppressed appetite [3 6]. LSG also improves comorbidities such as diabetes, hypertension and hyperlipidaemia and, though this may be a consequence of weight loss, the hormonal mechanisms that may contribute to this are yet to be elucidated [1, 6 8]. The largest published series on LSG consists of 540 patients and reports on complications, weight loss and comorbidity resolution but incorporates data from 17 centres and is thus subject to heterogeneity in operative technique, surgical experience and perioperative care [9, 10]. Other series have fewer patients and suffer from similar weaknesses [1, 2, 11]. These other studies are therefore unable to accurately quantify the occurrence of perioperative complications and have concluded that LSG is a safe procedure within the limitations

2 OBES SURG (2010) 20: of a small sample size. Small sample size also prevents the accurate assessment of late complications especially with regards to sleeve dilatation [12]. There are also minimal data on the results of LSG in the super-obese population [12, 13]. Importantly, postoperative outcomes are dependent on numerous factors other than the technical aspects of the operation and most studies do not clarify whether multidisciplinary support is provided to the patients both perioperatively and postoperatively in the long term [4, 14]. This is especially important in light of the American Society of Metabolic and Bariatric Surgery (ASMBS) requirements of multidisciplinary care being provided to patients to qualify as a centre of excellence [15]. As mentioned above, LSG has been shown to provide excellent outcomes with regards to obesity-related comorbidities. [1]. Most of the literature in this area concentrates on diabetes, hypertension, hyperlipidaemia and obstructive sleep apnoea. Our study also sought to characterise the impact of LSG on these comorbidities and made the subtle distinction between diabetes and impaired glucose tolerance which has not been uniformly done previously [1]. Alongside the previously studied comorbidities, our study also wished to investigate changes in stress urinary incontinence (SUI) in women. Obese women have a high prevalence of SUI due to chronically elevated intra-abdominal and intravesical pressures and constant stress on the pelvic floor contributing to organ prolapse [16 18]. Previous studies have shown improvement in symptoms of SUI following bariatric surgery [19 21]. However, there has been no investigation of SUI following LSG specifically. New Zealand has the third highest prevalence of obesity after the USA and Mexico with obesity being disproportionately prevalent in both indigenous Maori and Pacific peoples [22]. In response to this epidemic, bariatric surgery is being offered via government-funded schemes in public hospitals at no cost to the patient. Our institution has previously published our early experience with LSG and demonstrated its safety and early outcomes [23]. We wished to investigate the outcomes of LSG in our institution in a larger cohort with subgroup analysis of super-obese patients with regards to weight loss, complications, comorbidity resolution including urological outcomes as well as patient satisfaction. Methods Study Design Retrospective review of prospectively collected data regarding all LSGs conducted by three surgeons within our institution from March 2007 to September Approval for the surgery and study was granted by the institution s clinical board. Data Recorded Preoperative Characteristics Patient age, gender, ethnicity, preoperative weight, preoperative body mass index (BMI), excess BMI (ebmi; BMI points over 25 kg/m 2 ) and presence of comorbidities (hypertension, diabetes, hyperlipidaemia, obstructive sleep apnoea). In-hospital Outcomes Operating time, intraoperative blood transfusions, day-stay, 30-day complications as per the Clavien Dindo classification and late complications within the follow-up time [24, 25]. Outcomes Follow-up, weight loss, postoperative BMI, ebmi lost (percentage of BMI over 25 kg/m 2 lost) were recorded. Comorbidity resolution was defined as complete cessation of treatment/medication whilst improvement was defined as any reduction in medication use or treatment as these were deemed to be clinically significant measures. Patient satisfaction was measured on a Likert scale of 1 (not satisfied at all) to 10 (very satisfied). Subset Analysis A subset of patients with a median follow-up of 12 months was analysed separately for weight loss outcomes. Outcomes for super-obese patients (BMI, >50 kg/m 2 ) were also analysed separately. Stress Urinary Incontinence This was defined as the involuntary excretion or leakage of urine in inappropriate places or at inappropriate times [26]. Regularity was defined as more than twice per month [26]. The quantity of urine lost was not considered in the definition. Four predefined categories of severity were used: Minimal, no extra laundry; no extra pads or expenses; no restriction in activities because of incontinence. Slight, very small amount of extra laundry; pads worn only occasionally; no restriction in activities. Moderate, extra laundry; pads or expenses; some restriction in activities. Severe, extra laundry; pads or expenses; activities restricted;

3 1486 OBES SURG (2010) 20: required help from others. Point prevalence, severity and postoperative change were assessed as above using the validated questionnaire developed by Thomas et al. [26]. Treatment Details Patients greater than 18 years of age were selected as per the European consensus guidelines on surgery for severe obesity (BMI, >40 kg/m 2 or >35 kg/m 2 with comorbidities) [27]. Patients were required to be either non-smokers or have stopped smoking for at least 6 weeks preoperatively. Eligible patients were commenced on the Optifast programme for 2 weeks (Société des Produits Nestlé S.A., Vevey, Switzerland) and were required to lose 0.5 kg between outpatient appointments. Patients who did not satisfy these criteria remained on the waiting list. In addition to preoperative anaesthetic and surgical assessment, all eligible patients were seen preoperatively by a bariatric nurse specialist and bariatric dietician. The surgical technique was standardised between the operating surgeons and has been previously described [23]. Patients were seen postoperatively by the operating surgeon and were discharged when well, able to maintain adequate oral hydration and when adequate social supports were in place. Patients were assessed postoperatively at 2 weeks, 6 weeks and then at 3- to 6-monthly intervals or sooner if indicated. Statistical Analysis Statistical analysis was conducted using SPSS (SPSS Inc, Irvine, CA). All data has been presented with means and standard deviation. Where medians have been used, this has been specified. The Two-tailed Fisher s exact test and paired t test were used as appropriate. A p value of less than 0.05 was considered statistically significant, and all data were analysed on an intention to treat basis. Results Preoperative Characteristics Two hundred and fifty-three patients underwent LSG in the study period with 68 (27%) males and 185 (73%) females with a mean age of 44 years (SD, 9). There were 148 (59%) European patients, 54 (21%) Maori patients and 36 (14%) Pacific Islander patients. The mean preoperative patient weight was 142 kg (SD, 23), and the mean preoperative BMI was 50 kg/m 2 (SD, 7). One hundred fourteen (45%) patients were super obese (BMI, >50 kg/m 2 ). Patients had a mean ebmi of 25 kg/m 2 (SD, 7). In-hospital Outcomes Three surgeons performed the procedures (A=133, B=104, C=16) with a median operating time of 106 min (range, ). The median day-stay was 2 (range, 1 114) days. No patients required intraoperative blood transfusions and there was one conversion to open surgery. There were five grade I complications; ten grade II complications, 13 grade III complications and four grade IV complications with no deaths in this series. Grades III and IV complications are shown in Table 1 Late Complications Two patients developed strictures requiring endoscopic dilatation and there was one staple-line leak 6 weeks Table 1 Major complications Grade III complications (n=13) 2 cases of staple-line leak requiring with postoperative stenting 3 cases of staple-line leak requiring laparoscopy Postoperative bleeding requiring relaparoscopy 2 cases of postoperative bleeding requiring laparotomy 3 cases of stricture requiring endoscopic dilatation Inadvertent bowel injury requiring laparotomy Volvulus of sleeve requiring endoscopic correction Grade IV complications (n=4) Intensive care unit (ICU) admission for labile BP postoperatively Postoperative bleed with secondary myocardial infarct requiring ICU admission Staple-line leak requiring laparotomy and ICU admission Staple-line haematoma requiring laparotomy. Postoperative bleed from ulcerated transverse colon requiring emergency right hemicolectomy with ICU admission

4 OBES SURG (2010) 20: postoperatively requiring stenting. One patient was noted to have developed clinically significant sleeve dilatation 17 months after surgery and has been offered revision surgery. Weight Loss The mean patient follow-up was 9 months (range, 1 29). One hundred and seventy-one (68%) and 57 (23%) patients had a mean follow-up of 12 months and 18 months, respectively. The overall ebmi loss is as shown in Fig. 1. The mean postoperative weight loss was 40 kg (SD, 17), and the mean ebmi loss was 56% (SD, 22). Subgroup Analysis Within a subset of 171 patients from March 2007 March 2009 with a median follow-up of 12 months, the mean preoperative weight was 141 kg (SD, 23) and the mean BMI was 50 kg/m 2 (SD, 7). The mean postoperative weight loss was 41 kg (SD, 16) and mean ebmi loss was 59% (SD, 22). Patients with a follow-up time exceeding 1 year (n=76) had a mean postoperative weight loss of 46 kg (SD, 17) and a mean ebmi loss of 65% (SD, 24). Results in Super-Obese Patients There were 114 super-obese patients with a mean BMI of 56 kg/m 2 (SD, 5). The mean follow-up overall was 9 months (1 29) with 93 patients having a mean followup of 12 months. The mean postoperative weight loss was 45 kg (SD, 18), and the mean ebmi lost was 49% (SD, 21). There were significantly more grades III (n=7) and IV (n= 3) complications in super-obese patients compared with obese patients (p=0.02). Super-obese patients experienced more weight loss compared with other patients (45 vs. Excess BMI (%) Percentage of excess BMI remaining postoperatively 0 (n=105) 0-1 (n=85) (n=105)(n=75) (n=71) (n=67) (n=35) (n=82) Time (months) and No. of patients (n=21) Fig. 1 Percentage of excess BMI remaining postoperatively (n=9) >24 36 kg; p=0.02) but lost less mean ebmi (49% vs. 61%; p< 0.01). Fifty-three patients (46%) remained morbidly obese (BMI, >40 kg/m 2 ) postoperatively. Comorbidity Resolution Resolution and improvement was seen in diabetes, obstructive sleep apnoea, hyperlipidaemia and hypertension as shown in Table 2. Urological Outcomes SUI was reported preoperatively in 60 (32%) females. Complete resolution postoperatively was reported in 32 (53%) patients, and 22 (37%) women reported an improvement in symptoms as evidenced by decreasing severity as shown in Table 3. Patient Satisfaction Patient satisfaction was high with a median score of 10 (3 10). Discussion This study shows that LSG is a safe procedure which provides satisfactory weight loss and comorbidity resolution in the short and medium term. Super-obese patients achieve greater absolute weight loss but have less ebmi loss compared with patients with a BMI under 50 kg/m 2 and almost half the super-obese patients remain morbidly obese postoperatively. The perioperative surgical complication rate is significantly higher in super-obese patients. This is the first study to show marked improvement in symptoms of SUI amongst women following LSG. The implications of these findings are discussed below. The existing literature concerning LSG consists largely of small series with early and medium-term follow-up [1]. Larger, multi-centred studies are limited by heterogeneity in surgical care, surgeon-experience and by combining singlestage LSG with LSG being offered as a first-stage Table 2 Comorbidity resolution Comorbidity Improved Resolved Hypertension (n=113; 45%) 33 (29%) 54 (48%) Diabetes (n=81; 32%) 7 (9%) 66 (81%) Hyperlipidaemia (n=117; 46%) 6 (5%) 56 (48%) OSA (n=39; 15%) 19 (49%) 15 (38%) OSA obstructive sleep apnoea

5 1488 OBES SURG (2010) 20: Table 3 Prevalence and postoperative change in stress urinary incontinence All numbers represent absolute numbers of patients Degree of incontinence Prevalence No change Improved Resolved Minimal Slight Moderate Severe 1 1 procedure and for revision after other failed procedures [10, 11]. The largest published series that reports 5-year followup from LSG consists of 26 patients [28]. Meta-analyses are also influenced by the selection and publication bias of included retrospective studies [1, 29]. This study is the largest single-centre series of LSGs and includes the entire experience of our institution in offering LSG, thereby excluding any selection bias. Though a limitation of the study is the short follow-up, this series includes a comparatively large number of patients with a mean follow-up of 12 months (n=171) and 18 months (n=57) who allow us to draw conclusions about weight loss (See Fig. 1). Improvements in comorbidities can also be reliably assessed within the specified time frame as improvements in glucose homeostasis occur in the early postoperative period influencing both diabetes and hyperlipidaemia [30, 31]. Other studies have also not shown any clinically significant attrition in comorbidity improvement or resolution in the short to medium term once achieved, and our current results are comparable to our previously published cohort with a mean follow-up of 12 months [23]. This study is also the largest single-centre series of LSG in super-obese patients with the overall sample also having a mean BMI of 50 kg/m 2 and so more accurately reflects the early operative complication rate as well as the challenge of LSG in the super-obese population. The major complication rate (grades III and IV) in this series was 7%. Previous studies have reported a mean complication rate of 6.2% (0 21.7%)[1] and thus our results are similar to other published series. Stroh et al. report a surgical complication rate of 9.4% though this study incorporated revision LSGs and included 14 out of 17 institutions which had performed less than ten LSGs [11]. Sanchez-Santos et al. report a complication rate of 5.2% in a large multi-centred series of 540 patients and demonstrated staple-line reinforcement was associated with decreased complications [10]. Our study reports a comparable complication rate to previously published complication rates for laparoscopic Roux-en-Y bypass and bilio-pancreatic diversion [32, 33] though more recent single-centre series from high-volume academic centres have published lower complication rates for procedures such as laparoscopic Rouxen-Y bypass [34]. Any comparison of complication rates must also acknowledge the heterogeneity in defining, grading and assessing complications as well as potentially dissimilar patient populations [22, 35]. The incidence of late complications with only one case of clinically significant sleeve dilatation is a reassuring finding. The results of our series should also be considered in light of the super-obese patient population. There are minimal published data on the results of single-stage LSG in a super-obese population, though a BMI of greater than 50 kg/m 2 has previously been described as an independent predictor of complications [10]. Importantly, these complications are largely comprised of bleeding events, staple-line leaks and postoperative strictures and may indicate the potential operative complexity especially with an enlarged left liver lobe and greater intragastric pressures in superobese individuals [10, 36]. Despite greater absolute weight loss, super-obese patients lost less ebmi. Tagaya et al. also reported inferior weight-loss outcomes in super-obese patients in a small series of 30 patients whilst Langer et al. found no difference in weight-loss outcomes between super-obese and morbidly obese individuals is a series of 23 patients [12, 13]. The magnitude of weight loss reported in our series is similar to previous studies evaluating the efficacy of LSG as a first-stage procedure in super-obese patients [37, 38]. This suggests that LSG provides significant weight loss in super-obese patients but due to their high preoperative BMI, they are thought to have inferior outcomes as they lose mathematically less ebmi. As previously described by Akkary et al. and demonstrated by our study, an ebmi loss of approximately 50% still places many super-obese patients in the morbidly obese category [3]. These individuals thus may require a secondstage operation. Our study does, however, indicate that single-stage LSG can be performed in super-obese individuals with the reasonable expectation that many patients will not need any further bariatric surgery. Moreover, since all patients have continued to experience weight loss up to 18 months postoperatively as seen in Fig. 1, super-obese patients also may lose further weight. The significantly increased complication rate must be considered though super-obese individuals are at an increased risk of complications from other bariatric procedures too [39 41]. This is the first study to report on improvement in SUI following LSG. Previous studies have demonstrated the link between weight loss and improvement in SUI symptoms but

6 OBES SURG (2010) 20: few studies have explored the effect of bariatric surgery in particular on urological outcomes [19, 21]. Since the operative success of urinary incontinence surgery is decreased in the presence of obesity [42], further study is needed to determine whether bariatric surgery should be offered as a treatment for severe SUI in obese women and thus whether severe SUI constitutes an indication for bariatric surgery in obese women [19]. It is also important to determine whether the improvements seen are a consequence of weight loss alone. Future studies evaluating bariatric procedures should investigate urological endpoints including physiological measurement of voiding to determine procedure-specific outcomes for SUI. LSG provides early and medium-term weight loss with resolution of comorbidities in eligible candidates with acceptable, though inferior results in the super-obese population. The improvement in urological outcomes observed deserve further study. 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