A body mass index over 40 kg/m2 is defined as morbid obesity and morbid obesity continues to be a serious health problem worldwide [1].

Laparoscopic surgery has been used routinely in all surgical branches. Laparoscopic surgery, less post-operative pain, early recovery and it has advantages such as aesthetic value [2].

Carbon dioxide (CO2) during laparoscopic procedures is the most common gas used for pneumoperitoneum. Especially, in laparoscopic surgery, intra-abdominal pressure should be kept stable at 12 mmHg in morbidly obese patients because A prolonged increase in intra-abdominal pressure 12 mmHg is considered pathological. Normal intra-abdominal pressure is between 2-5 mmHg. Intra-abdominal pressure is higher in morbidly obese patients than in normal patients [3].

The increased intra-abdominal pressure during pneumoperitoneum has been shown in morbidly obese patients to result in changes renal, hepatic and cardiorespiratory functions more than normaly patients. Therefore, surgeons performing laparoscopy in morbidly obese patients should make appropriate intraoperative adjustments to minimize the adverse changes [4].

In this study, the effect of pneumoperitenium formed in laparoscopic surgery on kidney functions in morbidly obese patients was evaluated.

In our center, 40 morbidly obese patients in abdominal surgery were studied retrospectively. In these patients were divided into two groups:

• Group 1: Open surgery group

• Group 2: Laparoscopic surgery group

Between these two groups, demographic features, clinical features and postoperatively first day blood urea nitrogen levels, sodium levels, potassium levels, creatinine levels and creatinine clearance levels were compared.

Exclusion criteria were, patients with a body mass index below 40 and with a duration of surgery of over 120 minutes.

Statistical Analysis 

Statistical analysis SPSS 22.0 (SPSS for Windows, 2007, Chicago) was used for statistical analysis. Continuous variables which have normal distribution were presented as mean (standard deviation). Statistical analysis for the parametric variables was performed by the Student’s T-test. The qualitative variables were given as percent and the correlation between categorical variables was investigated by the chi-square test and Fisher’s exact test. Statistical significance level was defined as p˂0.05.

Mean age of the in patients with open surgery group were 40.5±10.09 years, in patients with laparoscopic surgery group were 41±9.36 years (p = 0.471).

There were 2 (10%) males and 18(90%) females in patients with open surgery group, there were 3 (15%) males and 17 (85%) females in patients with laparoscopic surgery group (p = 0.633).

The mean body mass index (BMI) were 44.79±3.36 kg/m2 in open surgery group, 45.57±4.00 kg/m2 in laparoscopic surgery group (p = 0.514).

Mean postoperatively first day blood urea nitrogen levels of in patients with open surgery group were 24.9±8.6 mg/dL, in patients with laparoscopic surgery group were 27.5±10 mg/dL (p = 0.516).

Mean postoperatively first day blood creatinine levels of in patients with open surgery group were 0.7±0.11 mg/dL, in patients with laparoscopic surgery group were 0.75±0.10 mg/dL (p = 0.917).

Mean postoperatively first day blood creatinine clearance levels of in patients with open surgery group were 89.5±8.6 mL/min, in patients with laparoscopic surgery group were 91.9±8.6 mL/min (p = 0.442).

Mean postoperatively first day sodium levels of in patients with open surgery group were 139.2±2.76 mEq/L, in patients with laparoscopic surgery group were 140.9±3.16 mEq/L (p = 0.808).

Mean postoperatively first day potassium levels of in patients with open surgery group were 4.06±0.41 mEq/L, in patients with laparoscopic surgery group were 4.23±0.38 mEq/L (p = 0.586). Table 1 shows comparison of open or laparoscopic surgery groups.

Table 1: Comparison of Open or Laparoscopic Surgery Groups

Overweight means disproportionally more weight in relation to body height and is quantified by the body mass index (BMI; weight in kilograms divided by length in squared meters, kg/m2) [5]. A BMI >25 kg/m2 represents overweight, >30 kg/m2 obesity and >40 kg/m2 morbid obesity. Morbid obesity is defined by the World Health Organization as patients with a BMI over 40 kg/m2. Morbid obesity continues to be a serious health problem (diabetes, cardiovascular diseases and psychological problems) worldwide and the number is increasing every year [6]. In our study, all patients were morbidly obese (BMI ˃40 kg/m2).

Laparoscopic surgery has been used routinely in all surgical branches. Laparoscopic surgery, less post-operative pain, early recovery and it has advantages such as aesthetic value [2,7]. Pneumoperitoneum with CO2 has been used in clinical practice since the introduction of laparoscopic cholecystectomy in the late 1980s. In laparoscopic surgery, the abdomen of patients was inflated with CO2 gas up to a standard maximum of 12 mmHg and pneumoperitoneum is formed [8,9]. In our study, all patients were done laparoscopic or open abdominal surgery. Duration of surgery of short than 120 minutes all of them. In this study, the abdomen of patients was inflated with CO2 gas up to a standard maximum of 12 mmHg and pneumoperitoneum is formed in laparoscopic group. In our study, between laparoscopic or open abdominal surgery groups the age, sex,body mass index, duration of surgery were not statistically significantly.

Laparoscopic surgery is a surgical procedure that should be performed with caution, especially in morbidly obese patients. Because patients already have high intra-abdominal pressure (Intra-abdominal pressure of morbidly obese patients is 2-3 times higher than normal patients). Attention should be paid to the hepatic, renal and cardiopulmonary systems, which are most affected by hypoperfusion. Blood urea nitrogen levels, sodium levels, potassium levels, creatinine levels and creatinine clearance levels are frequently used parameters to evaluate renal function [3,10-11]. In our study, between these two groups postoperatively first day blood urea nitrogen levels, sodium levels, potassium levels, creatinine levels and creatinine clearance levels were not statistically significantly.

Our study has several limitations. First, this study was retrospective. Second, the number of cases was small.

Despite the limitations, in this study, no negative effect of pneumoperitoneum formed in laparoscopic abdominal surgeries performed on morbidly obese patients was found on kidney functions. But, we think that surgeons performing laparoscopy in morbidly obese patients should make appropriate intraoperative adjustments to minimize adverse changes and work at pressures below 12 mmHg.

Ethical Approval

Ethics committee approval was not received because of retrospective design of the study.

Informed Consent

The author stated that the written consent was obtained from the patients presented with radiological images in the study.

Financial Disclosure

The authors declared that this study has received no financial support.

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