***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background / Aim : There is ample evidence in the recent literature that gum chewing after elective colonic anastomosis decreases postoperative ileus ( POI ) . But there are very few studies on small bowel anastomosis done in relaparotomy cases . This study aim ed to evaluate the effect of gum chewing on the duration of POI following small bowel anastomosis performed for the closure of intestinal stoma , made as temporary diversion in the selected cases of typhoid perforation peritonitis . Patients and Methods : Hundred patients undergoing elective small bowel anastomosis for the closure of stoma were r and omly assigned to the study group ( n=50 ) and the control group ( n=50 ) . The study group patients chewed gum thrice a day for 1 h each time starting 6 h after the surgery until the passage of first flatus . The control group patients had st and ard postoperative treatment . Results : Study and control group patients were comparable at inclusion . The mean time for the appearance of bowel sounds as well as the passage of first flatus was significantly shorter in the study group ( P=0.040 , P=0.006 ) . The feeling of hunger was also experienced earlier in study group cases ( P=0.004 ) . The postoperative hospital stay was shorter in the study group , but the difference was not significant ( P=0.059 ) . Conclusions : The cases of relaparotomy requiring additional adhesiolysis and small bowel anastomosis for stoma closure are benefited by postoperative gum chewing OBJECTIVE To investigate whether gum chewing affects the return of bowel function after complete staging surgery for gynecologic malignancies . METHODS A total of 149 patients undergoing abdominal complete surgical staging for various gynecological cancers were r and omized into a gum-chewing group ( n=74 ) or a control group ( n=75 ) . The patients chewed sugarless gum three times from the first postoperative morning until the first passage of flatus . Each chewing session lasted 30 min . Total abdominal hysterectomy with systematic pelvic and para-aortic lymphadenectomy was performed on all patients as part of complete staging surgery . Groups were compared in terms of time to first bowel movement time , first flatus and feces pass time , postoperative analgesic and antiemetic drug requirement , postoperative oral intake tolerance , mild ileus symptoms and hospital stay . RESULTS The mean time to flatus ( 34.0 ± 11.5 vs. 43.6 ± 14.0 h ; p<0.001 ) , mean time to defecation ( 49.6 ± 18.7 vs. 62.5 ± 21.5h ; p<0.001 ) , mean time to bowel movement ( 41.5 ± 15.7 vs. 50.1 ± 5.9h ; p=0.001 ) , mean time to tolerate diet ( 4.0 ± 0.8 vs. 5.0 ± 0.9 days ; p<0.001 ) , mean length of hospital stay ( 5.9 ± 1 vs. 7.0 ± 1.4 days ; p<0.001 ) were significantly reduced in patients that chewed gum compared with controls . Mild ileus symptoms were observed in 27 ( 36 % ) patients in the control group compared to 11(14.9 % ) patients in the gum-chewing group [ relative risk , 2.4 ; 95 % confidence interval , 1.2 - 4.5 ; p=0.004 ] . Severe symptoms were observed in two patients ( 2.7 % ) in the control group . CONCLUSIONS Gum chewing early in the postoperative period following elective total abdominal hysterectomy and systematic retroperitoneal lymphadenectomy hastens time to bowel motility and ability to tolerate feedings . This inexpensive and well-tolerated treatment should be added as an adjunct in postoperative care of gynecologic oncology Background Gum chewing after cesarean section may stimulate bowel motility and decrease duration of postoperative ileus . Objectives The current study assessed the effect of chewing sugar-free gum on the return of bowel function , where cesarean section had been performed in nulliparous women . Material s and Methods In a r and omized clinical trial , 60 patients , scheduled for cesarean section were r and omly divided in to 2 groups gum-chewing group ( n = 30 ) and control group ( n = 30 ) postoperatively . The patients in the gum-chewing group postoperatively chewed sugar free gum 3 times daily each time for 1 hour until discharge . The patients ' demographic characteristics , duration of surgery , mean hunger time , flatus and bowel motility were compared in the two groups . Results There was no significant difference between the 2 groups regarding patient demographics , intraoperative , and postoperative care . In the gum-chewing and the control group there was a significant difference in the mean postoperative interval of the first bowel movement ( 20.89 ± 8.8 versus 27.93 ± 9.3 hours , P = 0.004 ) , the first feeling of hunger ( 10.37 ± 6.0 versus 16.33 ± 9.3 hours , P = 0.005 ) , the first passage of flatus ( 25.02 ± 5.8 versus 31.08 ± 9.7 hours , P = 0.003 ) , and the first defecation ( 31.17 ± 5.3versus 40.08 ± 8.8 hours , P = 0.000 ) respectively , which were significantly shorter in the gum-chewing group compared to those of the control group . There were no major complications in either group . All patients in the gum-chewing group tolerated it without any major complications and side effects . Conclusions The study results demonstrated that bowel motility after cesarean section in nulliparous women can be accelerated by gum chewing which is a useful , inexpensive and well-tolerated method for mothers in post-cesarean section Background and purpose Postoperative bowel dysfunction is still a major unsolved problem following transperitoneal abdominal aortic surgery . We conducted this study to establish if gum chewing during the postoperative period promotes recovery of bowel function following abdominal aortic surgery . Methods The subjects were 44 patients who underwent elective abdominal aortic surgery . The patients were allocated to a control group ( n = 21 ) , who received st and ard postoperative care , or a “ gum group ” ( n = 23 ) , who received st and ard postoperative care and were also given gum to chew three times a day from postoperative day ( POD ) 0–5 . Results The patient characteristics , intraoperative , and postoperative care were equivalent in both groups . Flatus was passed on POD 1.49 in the gum group and on POD 2.35 in the control group ( P = .0004 ) and the time to oral intake was 3.09 days in the gum group and 3.86 days in the control group ( P = .023 ) . The number of days to full mobilization in the hospital room was 3.35 versus 5.59 for the gum and control groups , respectively ( P < .0001 ) . Conclusions Gum chewing enhances early recovery of bowel function following transperitoneal abdominal aortic surgery . Moreover , it is a physiologically sound , safe , and an inexpensive part of the postoperative care Background / Objective : Postoperative ileus ( POI ) after colorectal surgery is associated with prolonged hospital stay and increased costs . The aim of this study is to investigate pre- , intra- , and postoperative risk factors associated with the development of POI in patients undergoing laparoscopic partial colectomy .  Methods : Patients operated between 2004 and 2008 were retrospectively identified from a prospect ively maintained data base , and clinical , metabolic , and pharmacologic data were obtained . Postoperative ileus was defined as the absence of bowel function for 5 or more days or the need for reinsertion of a nasogastric tube after starting oral diet in the absence of mechanical obstruction . Associations between likelihood of POI and study variables were assessed univariably by using & khgr;2 tests , Fisher exact tests , and logistic regression models . A scoring system for prediction of POI was constructed by using a multivariable logistic regression model based on forward stepwise selection of preoperative factors . Results : A total of 413 patients ( mean age , 58 years ; 53.5 % women ) were included , and 42 ( 10.2 % ) of them developed POI . Preoperative albumin , postoperative deep-vein thrombosis , and electrolyte levels were associated with POI . Age , previous abdominal surgery , and chronic preoperative use of narcotics were independently correlated with POI on multivariate analysis , which allowed the creation of a predictive score . Patients with a score of 2 or higher had an 18.3 % risk of POI ( P < 0.001 ) . Conclusion : Postoperative ileus after laparoscopic partial colectomy is associated with specific preoperative and postoperative factors . The likelihood of POI can be predicted by using a preoperative scoring system . Addressing the postoperative factors may be expected to reduce the incidence of this common complication in high-risk patients Postoperative ileus ( POI ) is a common complication after major abdominal surgery . Gum chewing has been shown to stimulate bowel motility and decrease duration of POI after abdominal surgery . We evaluated the effect of gum chewing in reducing the time to first flatus and on oral calorie intake in patients undergoing living or deceased donor liver transplantation . Patients were r and omized into the sham feeding group or the control group . The sham feeding group chewed two pieces of xylitol flavored gum for 15 minutes , three times a day after extubation until oral nutrition was tolerated . The control group received the same routine care except for the gum chewing .  Fifty‐nine patients were r and omized into the sham feeding group ( n=30 ) or the control group ( n=29 ) . There was no difference in the time to first flatus ( 72 [ 66.1‐82.9 ] hours vs 69.0 [ 57.6‐77.2 ] hours , P=.422 ) . Cumulative energy intake ( 2.8 [ 5.8‐23.2 ] % vs 10.0 [ 8.5‐15.9 ] % , P=.695 ) and length of intensive care unit stay ( 4.2 [ 3.9‐5.3 ] days vs 4.0 [ 6.7‐4.5 ] days , P=.077 ) were also similar . In conclusion , sham feeding with gum chewing did not shorten the duration of POI nor facilitate oral intake after liver transplantation . ( Clinical trials.gov number : NCT 01956643 ) HYPOTHESIS Gum chewing after elective open colon resection may stimulate bowel motility and decrease duration of postoperative ileus . DESIGN AND SETTING Prospect i ve , r and omized study in a community-based teaching hospital . PATIENTS Thirty-four patients undergoing elective open sigmoid resections for recurrent diverticulitis or cancer . MAIN OUTCOME MEASURES First feelings of hunger , time to first flatus , time to first bowel movement , length of hospital stay , and complications . RESULTS A total of 34 patients were r and omized into 2 groups : a gum-chewing group ( n = 17 ) or a control group ( n = 17 ) . The patients in the gum-chewing group chewed sugarless gum 3 times daily for 1 hour each time until discharge . Patient demographics , intraoperative , and postoperative care were equivalent between the 2 groups . All gum-chewing patients tolerated the gum . The first passage of flatus occurred on postoperative hour 65.4 in the gum-chewing group and on hour 80.2 in the control group ( P = .05 ) . The first bowel movement occurred on postoperative hour 63.2 in the gum-chewing group and on hour 89.4 in the control group ( P = .04 ) . The first feelings of hunger were felt on postoperative hour 63.5 in the gum-chewing group and on hour 72.8 in the control group ( P = .27 ) . There were no major complications in either group . The total length of hospital stay was shorter in the gum-chewing group ( day 4.3 ) than in the control group ( day 6.8 ) , ( P = .01 ) . CONCLUSIONS Gum chewing speeds recovery after elective open sigmoid resection by stimulating bowel motility . Gum chewing is an inexpensive and helpful adjunct to postoperative care after colectomy Aim : Postoperative ileus is an important factor of complications following gastrointestinal procedures . Its pathophysiology and the parameters , which may impact on its duration , remain unclear . The aim of this study was to measure the role of various clinical determinants on restoration of intestinal function after  elective colorectal surgery .  Methods : From July 2002 to September 2003 , all patients who underwent laparotomy for colectomy ( laparoscopic resections excluded ) with either an ileotransverse , colocolic , or high colorectal anastomosis  were entered in this prospect i ve study . The intervals in hours between the end of the surgical procedure and passing of flatus ( PG ) and passing of stool ( PS ) were recorded 
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There was statistical evidence of heterogeneity in all analyses other than TBS in CRS.There was little difference in mortality , infection risk and readmission rate between the groups .
Some studies reported reduced nausea and vomiting and other complications in the intervention group .
CG was generally well-tolerated by participants .
Sensitivity analysis of ERAS studies showed a smaller effect size on TFF , larger effect size on TBM , and no difference between groups for LOHS.Meta-regression analyses indicated that surgical site is associated with the extent of the effect size on LOHS ( all surgical subgroups ) , and TFF and TBM ( CS and CRS subgroups only ) .
There was no evidence that ROB score predicted the extent of the effect size on any outcome .
Neither variable explained the identified heterogeneity between studies .
This review identified some evidence for the benefit of postoperative CG in improving recovery of GI function .
Many components of the ERAS programme also target ileus , therefore the benefit of CG alongside ERAS may be reduced , as we observed in this review .
Therefore larger , better quality RCTS in an ERAS setting in wider surgical disciplines would be needed to improve the evidence base for use of CG after surgery