Body Mass Index and Obesity Surgery Mortality Risk Score in Perioperative Complications of Laparoscopic Sleeve Gastrectomy

The term obesity is defined as body mass index (BMI) 30 and over, and morbid obesity is considered as BMI greater than 40 (1).Its incidence in the general population is approximately 20% according to Organisation for data of Economic Co-operation and Development (OECD) countries and unfortunately, it is increasing worldwide (2). Obesity should not be thought ofas a single disorderasit is related tomany disorders like hypertension, diabetes, obstructive sleep apnea, cardiovascular diseases, and increased risk of malignancies (1).For years people have struggled with obesitywithboth metabolic and physical problems. Surgical treatment is the most effective long-term therapeutic treatment in current and modern medicine of obesity and obesity-related diseases as the last resort.(3-5). Roux-en-y gastrojejunostomy is the method that has been applied for many years and there isconsensus on its effect.However, in recent years, laparoscopic sleeve gastrectomy (LSG) has an increasing number of procedures with a short learning curve and it is the most performed surgical technique all over the world and also in Turkey (2,6).

Unfortunately, like any surgical procedure, this surgery has its own complications.Although being performed frequently increases the experience of surgeons, this situation cannot reduce the risk of complications of surgery to zero. In morbid obesity patients, the risk of any complications in all surgical procedures is higher than withother patients who were not morbidly obese. Due to these complications, prolonged hospital stays, increased reapplications to the hospital, reoperations and deaths can result(5,7). Despite both an increased risk of complications according to obesity and the risk of specific complications due to sleeve gastrectomy, laparoscopic sleeve gastrectomy is associated with acceptable postoperative morbidity and mortality rates (8).

Various classifications have been described in the literature for complications after surgery.In one of these classifications, according to Clavien-Dindo (CD) Classification, complications are divided into two groups as major and minor. (1, 9)(Table 1). This classification can be applied to bariatric and metabolic surgeries as withall surgery types. Especially major complications in this classification are life-threatening situations and their early detection is important (8).

In fact, surgeons do not want to encounter mortality in any of their patients. In this respect, DeMaria et al. developed an easily applicable mortality risk scoring system, which is consisted of five items (age ≥45 years, male sex, body mass index (BMI) ≥ 50 kg / m2, arterial hypertension, and risk factors for pulmonary thromboembolism) and can be used for the pre-operative determination of risky patients in obesity surgery(Obesity Surgery Mortality Risk Score; OR-MRS) (8,10,11).

In this study, it is aimed to determine the perioperative complications seen in the laparoscopic sleeve gastrectomy patients that we performed in our clinic without being discharged from the hospital and to evaluate the treatment processes of the complications under literature. In addition, whether the OS-MRS risk assessment scale and BMI had a role indetermining perioperative complications before discharge was investigated.

Material - Method Our study was carried out with the approval numbered 13281952-929 from Elazig Training and Research Hospital. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. 1752 patients who met the criteria of patient selection in terms of obesity and metabolic disease surgery, operated in the Elazığ Training and Research Hospital General Surgery Clinic between January 2016 and October 2018 were evaluated retrospectively. Patients' data were obtained from epicrisis forms in the hospital computer system, patient follow-up charts and patient files. Data for OS-MRS and Clavien Dindo complication classification were obtained from patient follow-up charts, patient files and hospital computer records. Patients' demographic data (age, sex), presence of comorbidities, complications (wound complications, thromboembolic events, leakage from anastomosis, splenic infarction proven by imaging methods, bleeding detected due to low hemoglobin and hematocite values during follow-up, acute renal failure due to deterioration in biochemical parameters) seen in follow up period before discharge (postoperative first 72 hours), complication type (major and minor), whether emergency surgery was performed, BMI values, postoperative hospitalization and OS-MRS. Additionally, while grouping according to BMI values, patients with BMI values below 40 were excluded and three groups with BMI values of 40 - 45 kg / m\^2, 45 - 50 kg / m\^2 and 50 kg / m\^2 and above were created. It was investigated whether there were any complications among these groups and the presence of major or minor complications by CD classification. 1617 patients who met the inclusion criteria were evaluated.

IBM Statistical Package for Social Sciences (SPSS) 20.0 was used for statistical evaluation. Kolmogorow-Smirnov test results were examined in terms of the suitability of the groups for normal distribution. In comparisons between groups, independent sample t-test or Mann Whitney U test was used to evaluate numerical data according to normality test. In the evaluation of categorical data, chi-square analysis and Fischer's exact test were performed. In terms of the relation between complication formation and BMI, univariate analysis and multivariate analysis were performed. Numerical data were given as mean ± standard deviation (ss) (minimum - maximum values) or median (minimum - maximum values) according to normality test. Categorical data are given as count (n) and percentage (%).

Eligibility Criteria:
Inclusion Criteria:

* Patients whose data was available
* Morbid obesity patients who were operated with surgical technique laparoscopic sleeve gastrectomy

Exclusion Criteria:

* Patients whose data was not available
* Patients who were operated with other types of bariatric metabolic surgery
* Patients who left the hospital due to referral
* Patients whose OS-MRS scale wasn't calculated
* Patients whose American Society of Anesthesiologists (ASA) score was 4 or greater