Original Article Received: March 23, 2017 Accepted after revision: July 14, 2017 Published online: August 11, 2017
Gynecol Obstet Invest DOI: 10.1159/000479509
Do We Need Mechanical Bowel Preparation before Benign Gynecologic Laparoscopic Surgeries? A Randomized, Single-Blind, Controlled Trial Baris Mulayim Burak Karadag Department of Obstetrics and Gynecology, Saglık Bilimleri University, Antalya Education and Research Hospital, Antalya, Turkey
Abstract Aims: The primary objective of this study was to compare the effect of mechanical bowel preparation (MBP) with oral sodium phosphate (NaP) solution vs. MBP with NaP enema vs. fasting only with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery in patients undergoing benign gynecologic laparoscopic procedures. Methods: The patients were randomized into one of 3 groups: oral NaP, NaP enema, or fasting only. The primary surgeon and assistant(s) remained blinded to the randomization assignments. Intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were assessed using a surgeon questionnaire based on Visual Analog Scales. Results: We enrolled 293 women, of whom 278 were randomized to receive oral NaP solution (n = 96), undergo NaP enema (n = 92), or perform fasting only (n = 90). No significant differences were found between the 3 groups. Conclusions: No differences were ob-
© 2017 S. Karger AG, Basel E-Mail [email protected] www.karger.com/goi
served among patients who underwent MBP with oral NaP or NaP enema and those without MBP, with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. No benefit of MBP was found when removing large uteri or when operating on patients with a high body mass index. © 2017 S. Karger AG, Basel
Introduction
Mechanical bowel preparation (MBP) has been used for many years; however, its rationale has not been proven in patients undergoing laparotomy and in those undergoing laparoscopic surgery [1–3]. MBP is believed to decrease the risk of complications, such as anastomotic leakage and surgical site infection in gastrointestinal surgery; however, even this supposed beneficial effect is controversial [4]. Unlike in gastrointestinal surgery, MBP is mainly used in gynecologic laparoscopic surgery for adequate visualization of the surgical field and bowel handling, which is believed to make the procedure easier or faster. Baris Mulayim, MD Associate Professor, Department of Obstetrics and Gynecology Saglık Bilimleri University, Antalya Education and Research Hospital Varlık Mh., Kazım Karabekir Caddesi, TR–07100 Antalya (Turkey) E-Mail brsmlym @ yahoo.com
Downloaded by: Univ.of Adelaide 129.127.145.240 - 8/25/2017 10:35:25 PM
Keywords Laparoscopy · Mechanical bowel preparation · Benign gynecological surgery · Uterus · Body mass index
Materials and Methods This prospective, randomized, single-blind, controlled clinical trial was conducted between June 2016 and December 2016 at Antalya Education and Research Hospital. The Local Ethics Committee of the hospital issued an approval (2016-115) before any study-related procedures were conducted. The participants provided written informed consent before participation. Study Population, Patient Selection, and Randomization Non-pregnant women aged 18–80 years undergoing elective laparoscopic surgery for benign gynecologic conditions were included in this study. The exclusion criteria included inability to take an oral MBP agent or undergo enema for MBP, inability to complete the MBP regimen, suspected malignancy or pregnancy, associated non-gynecological surgical pathologies, and suspected deep infiltrative endometriosis. On the day before surgery, the patients were randomized into one of 3 groups: oral NaP, NaP enema, or fasting only (no MBP).
2
Gynecol Obstet Invest DOI: 10.1159/000479509
Randomization assignments were made by using a random number generator (simple randomization) in the ward with sealed, opaque envelopes. When a patient consented to participate in the study, a service nurse wrote the patient’s name on the next envelope in a series of consecutively numbered envelopes and then opened the envelope to reveal the group allocation. The primary surgeon (B.M.) and the assistant(s) remained blinded to the randomization assignments. Patients randomized to the oral NaP group were instructed to ingest 45 mL NaP solution (from B.T., Yenişehir Laboratories, Ankara, Turkey) in the evening of the day before surgery. Patients randomized to the NaP enema group were instructed to selfadminister a single 177 mL NaP enema (from B.T., Yenişehir Laboratories, Ankara, Turkey) rectally at bedtime in the evening before the surgery. All patients randomized to the 3 groups were allowed a clear liquid diet in the evening before surgery and were told not to ingest anything, including liquids, after midnight. Patients with chronic medical conditions were allowed to sip water for taking routine medications on the morning of surgery. All surgical procedures were carried out by the same primary surgeon (B.M.). At the end of surgery, the primary surgeon completed a questionnaire that required providing ratings on intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. A 5-point Visual Analog Scale (VAS) was used for this evaluation (1, poor/very difficult; 2, sufficient/ moderately difficult; 3, medium/average difficulty; 4, good/easy; 5, excellent/very easy). Finally, the surgeon was asked to guess whether the patient had performed MBP or not. On the surgery day, all patients were interviewed by an independent investigator about their preoperative overall discomfort levels, evaluated by using a 5-point VAS (1, poor/very difficult; 2, sufficient/moderately difficult; 3, medium/average difficulty; 4, good/easy; 5, excellent/very easy). Finally, patients in the MBP group (oral NaP and NaP enema) were asked if they would recommend their MBP type to other patients undergoing the same procedure. Power Analysis Our primary objective was to detect differences among the 3 groups with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. Therefore, power analysis and sample size estimation were conducted for the primary objective. Power calculation was performed by using MedCalc 11.1.1.0 (MedCalc Statistical Software, Mariakerke, Belgium). In a prior study, Oliveira et al. [7] reported adequate intraoperative visualization of the surgical field in 80% of patients with bowel preparation. By using this rate, assuming a margin of equivalence of 20% with alpha value set at 0.05, our study would be adequately powered (at least 80%) with 82 patients in each group (n = 246). To account for dropout and non-adherence, we aimed to recruit 290 women. Statistical Analysis Data were recorded and analyzed by using SPSS 18.0 for Windows (SPSS Inc., Chicago, IL, USA). Continuous variables were expressed as mean, median, minimum, and maximum, whereas categorical variables were expressed as percentages and frequencies. The Shapiro-Wilk test was used to assess the equality of variance of the data. When appropriate, and according to data distribution, analysis of variance was used for demographic com-
Mulayim/Karadag
Downloaded by: Univ.of Adelaide 129.127.145.240 - 8/25/2017 10:35:25 PM
However, Muzii et al. [5] found no significant benefit of oral MBP over no bowel preparation with regard to surgical field visualization and surgical difficulty. Moreover, MBP was reported to significantly increase the preoperative discomfort in patients undergoing mostly diagnostic gynecologic laparoscopic procedures and ovarian cystectomy [5]. Subsequent studies have compared the effects of different MBPs (e.g., oral vs. enema) on the quality of the surgical field or bowel handling and preoperative discomfort in patients undergoing advanced gynecologic laparoscopic surgeries. The routine use of MBP for gynecologic laparoscopic surgery has not been recommended [3], but some questions remain to be answered. No controlled trial in the literature has compared the effects of MBP with oral sodium phosphate (NaP) vs. NaP enema with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. Moreover, one of the recent studies by Ryan et al. [6] concerning MBP before total laparoscopic hysterectomy suggests the need for investigations on the use of MBP when removing large uteri or when operating on patients with a high body mass index (BMI). The primary objective of the present study was to compare the effect of MBP with oral NaP solution vs. MBP with NaP enema vs. fasting only with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery in patients undergoing benign gynecologic laparoscopic procedures. The secondary objective was to compare perioperative parameters and patient discomfort scores in the preoperative period among the 3 intervention groups.
293 eligible 8 not meeting inclusion criteria 7 declined to participate
278 randomized
96 oral NaP 9 unable to complete oral NaP
4 unable to complete NaP enema
2 conversion to laparotomy Analyzed
92 NaP enema
85
90 fasting only 1 conversion to laparotomy
88
89
Fig. 1. The study flow diagram.
Results
A total of 293 patients were evaluated for enrollment in this study; however, only 262 patients completed the study. The study flow diagram is shown in Figure 1. The 3 study groups were similar with respect to age, BMI, parity, medical history, number of previous abdominal surgeries, type of surgical procedure, operative time, estimated blood loss, hemoglobin difference, uterine weight, and length of hospital stay. The demographic and surgical data of patients are shown in Table 1. The results of assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery among the 3 groups based on VAS are shown in Table 2. No significant difference was found among the 3 groups with respect to intraoperative visualization of the surgical field, ease of bowel handling, or overall ease of surgery based on the VAS scores obtained from the primary surgeon immediately after the operation (p = 0.926, p = 0.4, and p = 0.634, respectively). MBP before Laparoscopy
Intraoperative visualization of the surgical field was rated as “good (4)” or “excellent (5)” in 57 (67.1%) women of the oral NaP group, 62 (70.5%) women of the NaP enema group, and 58 (65.2%) women of the fasting only group (p = 0.749). The primary surgeon had 51.5% accuracy in guessing whether MBP was used. The results of the assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were not different among the 3 groups in both obese (BMI >30 kg/m2) and non-obese (BMI ≤30 kg/m2) patients. The results are shown in Table 3. In another subgroup analysis, the results of the assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were also not different among the 3 groups when removing small (uterine weight
Gynecol Obstet Invest DOI: 10.1159/000479509
Do We Need Mechanical Bowel Preparation before Benign Gynecologic Laparoscopic Surgeries? A Randomized, Single-Blind, Controlled Trial Baris Mulayim Burak Karadag Department of Obstetrics and Gynecology, Saglık Bilimleri University, Antalya Education and Research Hospital, Antalya, Turkey
Abstract Aims: The primary objective of this study was to compare the effect of mechanical bowel preparation (MBP) with oral sodium phosphate (NaP) solution vs. MBP with NaP enema vs. fasting only with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery in patients undergoing benign gynecologic laparoscopic procedures. Methods: The patients were randomized into one of 3 groups: oral NaP, NaP enema, or fasting only. The primary surgeon and assistant(s) remained blinded to the randomization assignments. Intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were assessed using a surgeon questionnaire based on Visual Analog Scales. Results: We enrolled 293 women, of whom 278 were randomized to receive oral NaP solution (n = 96), undergo NaP enema (n = 92), or perform fasting only (n = 90). No significant differences were found between the 3 groups. Conclusions: No differences were ob-
© 2017 S. Karger AG, Basel E-Mail [email protected] www.karger.com/goi
served among patients who underwent MBP with oral NaP or NaP enema and those without MBP, with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. No benefit of MBP was found when removing large uteri or when operating on patients with a high body mass index. © 2017 S. Karger AG, Basel
Introduction
Mechanical bowel preparation (MBP) has been used for many years; however, its rationale has not been proven in patients undergoing laparotomy and in those undergoing laparoscopic surgery [1–3]. MBP is believed to decrease the risk of complications, such as anastomotic leakage and surgical site infection in gastrointestinal surgery; however, even this supposed beneficial effect is controversial [4]. Unlike in gastrointestinal surgery, MBP is mainly used in gynecologic laparoscopic surgery for adequate visualization of the surgical field and bowel handling, which is believed to make the procedure easier or faster. Baris Mulayim, MD Associate Professor, Department of Obstetrics and Gynecology Saglık Bilimleri University, Antalya Education and Research Hospital Varlık Mh., Kazım Karabekir Caddesi, TR–07100 Antalya (Turkey) E-Mail brsmlym @ yahoo.com
Downloaded by: Univ.of Adelaide 129.127.145.240 - 8/25/2017 10:35:25 PM
Keywords Laparoscopy · Mechanical bowel preparation · Benign gynecological surgery · Uterus · Body mass index
Materials and Methods This prospective, randomized, single-blind, controlled clinical trial was conducted between June 2016 and December 2016 at Antalya Education and Research Hospital. The Local Ethics Committee of the hospital issued an approval (2016-115) before any study-related procedures were conducted. The participants provided written informed consent before participation. Study Population, Patient Selection, and Randomization Non-pregnant women aged 18–80 years undergoing elective laparoscopic surgery for benign gynecologic conditions were included in this study. The exclusion criteria included inability to take an oral MBP agent or undergo enema for MBP, inability to complete the MBP regimen, suspected malignancy or pregnancy, associated non-gynecological surgical pathologies, and suspected deep infiltrative endometriosis. On the day before surgery, the patients were randomized into one of 3 groups: oral NaP, NaP enema, or fasting only (no MBP).
2
Gynecol Obstet Invest DOI: 10.1159/000479509
Randomization assignments were made by using a random number generator (simple randomization) in the ward with sealed, opaque envelopes. When a patient consented to participate in the study, a service nurse wrote the patient’s name on the next envelope in a series of consecutively numbered envelopes and then opened the envelope to reveal the group allocation. The primary surgeon (B.M.) and the assistant(s) remained blinded to the randomization assignments. Patients randomized to the oral NaP group were instructed to ingest 45 mL NaP solution (from B.T., Yenişehir Laboratories, Ankara, Turkey) in the evening of the day before surgery. Patients randomized to the NaP enema group were instructed to selfadminister a single 177 mL NaP enema (from B.T., Yenişehir Laboratories, Ankara, Turkey) rectally at bedtime in the evening before the surgery. All patients randomized to the 3 groups were allowed a clear liquid diet in the evening before surgery and were told not to ingest anything, including liquids, after midnight. Patients with chronic medical conditions were allowed to sip water for taking routine medications on the morning of surgery. All surgical procedures were carried out by the same primary surgeon (B.M.). At the end of surgery, the primary surgeon completed a questionnaire that required providing ratings on intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. A 5-point Visual Analog Scale (VAS) was used for this evaluation (1, poor/very difficult; 2, sufficient/ moderately difficult; 3, medium/average difficulty; 4, good/easy; 5, excellent/very easy). Finally, the surgeon was asked to guess whether the patient had performed MBP or not. On the surgery day, all patients were interviewed by an independent investigator about their preoperative overall discomfort levels, evaluated by using a 5-point VAS (1, poor/very difficult; 2, sufficient/moderately difficult; 3, medium/average difficulty; 4, good/easy; 5, excellent/very easy). Finally, patients in the MBP group (oral NaP and NaP enema) were asked if they would recommend their MBP type to other patients undergoing the same procedure. Power Analysis Our primary objective was to detect differences among the 3 groups with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. Therefore, power analysis and sample size estimation were conducted for the primary objective. Power calculation was performed by using MedCalc 11.1.1.0 (MedCalc Statistical Software, Mariakerke, Belgium). In a prior study, Oliveira et al. [7] reported adequate intraoperative visualization of the surgical field in 80% of patients with bowel preparation. By using this rate, assuming a margin of equivalence of 20% with alpha value set at 0.05, our study would be adequately powered (at least 80%) with 82 patients in each group (n = 246). To account for dropout and non-adherence, we aimed to recruit 290 women. Statistical Analysis Data were recorded and analyzed by using SPSS 18.0 for Windows (SPSS Inc., Chicago, IL, USA). Continuous variables were expressed as mean, median, minimum, and maximum, whereas categorical variables were expressed as percentages and frequencies. The Shapiro-Wilk test was used to assess the equality of variance of the data. When appropriate, and according to data distribution, analysis of variance was used for demographic com-
Mulayim/Karadag
Downloaded by: Univ.of Adelaide 129.127.145.240 - 8/25/2017 10:35:25 PM
However, Muzii et al. [5] found no significant benefit of oral MBP over no bowel preparation with regard to surgical field visualization and surgical difficulty. Moreover, MBP was reported to significantly increase the preoperative discomfort in patients undergoing mostly diagnostic gynecologic laparoscopic procedures and ovarian cystectomy [5]. Subsequent studies have compared the effects of different MBPs (e.g., oral vs. enema) on the quality of the surgical field or bowel handling and preoperative discomfort in patients undergoing advanced gynecologic laparoscopic surgeries. The routine use of MBP for gynecologic laparoscopic surgery has not been recommended [3], but some questions remain to be answered. No controlled trial in the literature has compared the effects of MBP with oral sodium phosphate (NaP) vs. NaP enema with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery. Moreover, one of the recent studies by Ryan et al. [6] concerning MBP before total laparoscopic hysterectomy suggests the need for investigations on the use of MBP when removing large uteri or when operating on patients with a high body mass index (BMI). The primary objective of the present study was to compare the effect of MBP with oral NaP solution vs. MBP with NaP enema vs. fasting only with respect to intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery in patients undergoing benign gynecologic laparoscopic procedures. The secondary objective was to compare perioperative parameters and patient discomfort scores in the preoperative period among the 3 intervention groups.
293 eligible 8 not meeting inclusion criteria 7 declined to participate
278 randomized
96 oral NaP 9 unable to complete oral NaP
4 unable to complete NaP enema
2 conversion to laparotomy Analyzed
92 NaP enema
85
90 fasting only 1 conversion to laparotomy
88
89
Fig. 1. The study flow diagram.
Results
A total of 293 patients were evaluated for enrollment in this study; however, only 262 patients completed the study. The study flow diagram is shown in Figure 1. The 3 study groups were similar with respect to age, BMI, parity, medical history, number of previous abdominal surgeries, type of surgical procedure, operative time, estimated blood loss, hemoglobin difference, uterine weight, and length of hospital stay. The demographic and surgical data of patients are shown in Table 1. The results of assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery among the 3 groups based on VAS are shown in Table 2. No significant difference was found among the 3 groups with respect to intraoperative visualization of the surgical field, ease of bowel handling, or overall ease of surgery based on the VAS scores obtained from the primary surgeon immediately after the operation (p = 0.926, p = 0.4, and p = 0.634, respectively). MBP before Laparoscopy
Intraoperative visualization of the surgical field was rated as “good (4)” or “excellent (5)” in 57 (67.1%) women of the oral NaP group, 62 (70.5%) women of the NaP enema group, and 58 (65.2%) women of the fasting only group (p = 0.749). The primary surgeon had 51.5% accuracy in guessing whether MBP was used. The results of the assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were not different among the 3 groups in both obese (BMI >30 kg/m2) and non-obese (BMI ≤30 kg/m2) patients. The results are shown in Table 3. In another subgroup analysis, the results of the assessments of intraoperative visualization of the surgical field, ease of bowel handling, and overall ease of surgery were also not different among the 3 groups when removing small (uterine weight
