Gum chewing and gastrointestinal function following caesarean delivery: a systematic review and meta-analysis

Efficacy and safety of preoperative chewing gum for undergoing elective surgery: A meta-analysis of randomised controlled trials

AIMS AND OBJECTIVES

This meta-analysis aimed to investigate the safety and feasibility of preoperative chewing gum in adult patients undergoing elective surgery.

BACKGROUND

Postoperative chewing gum has been shown to be safe and effective for most surgeries, while the safety and efficacy of preoperative chewing gum are still controversial.

DESIGN

A meta-analysis of randomised controlled trials was performed.

NO PATIENT OR PUBLIC CONTRIBUTION

This was a meta-analysis involving no people or animals.

METHODS

The literature search was performed in 9 databases from inception to July 2022. Randomised controlled trials that compared the safety and efficacy of preoperative chewing gum and preoperative chewing no gum in adult patients undergoing elective surgery were included. The study was reported in compliance with PRISMA statement.

TRIAL REGISTRATION

PROSPERO CRD42022330223.

RESULTS

Fourteen trials involving 1433 adult patients who undergo elective surgery were pooled in this meta-analysis. The results showed that preoperative chewing gum group resulted in no significant difference in gastric pH (p = .13) and gastric fluid volume (p = .25) compared with non-gum-chewing group. In comparison with the non-gum-chewing group, the gum-chewing group was associated with shorter preoperative thirst score (p = .02), lower incidence of postoperative nausea (p = .0004), lower incidence of postoperative sore throat, lower incidence of postoperative hoarseness, lower postoperative pain score, shorter first postoperative anal exhaust time (p < .00001), shorter first postoperative defecation time (p < .00001) and shorter hospital days (p = .02).

CONCLUSIONS

Preoperative chewing gum was associated with lower discomforts and complication rates, without increasing gastric pH and gastric fluid volume. This strategy may be an innovative, feasible and safe choice for elective surgery in adults.

RELEVANCE TO CLINICAL PRACTICE

This study's results could be used as an evidence for the implementation of preoperative chewing gum in perioperative care for adult patients undergoing elective surgery.

Are Paula method exercises effective for gastrointestinal reactivation post-elective cesarean delivery? Randomized controlled trial

AIM

To examine the effectiveness of the Paula Method exercises in comparison to standard care on resumption of gastrointestinal (GI) activity in women postelective caesarean delivery (CD).

DESIGN

Randomized controlled trial on a postpartum unit of a university medical centre.

METHODS

Sixty-four women following elective CD performed under regional anaesthesia were recruited between 2 February-3 July 2018. Participants were randomized into two groups: The Paula Method exercise group (intervention group) and the control group. Women in the intervention group performed circular muscle exercises according to the Paula Method and received standard care, while those in the control group were treated only with standard care. Time to first bowel sounds, passage of first flatus and first defecation after CD were measured.

RESULTS

A significant difference was found in the time to passage of first flatus, in favour of the intervention group (24.07 [6.85] hours versus 39.07 [10.37] hours; p < .001). No significant differences between the groups were found for other main outcome measures.

CONCLUSION

Paula Method exercises post CD can serve as natural and convenient alternative to the standard, conservative treatment to promote resumption of GI activity.

IMPACT

CD can be associated with postoperative ineffective peristalsis that can lead to a paralytic ileus. Since standard methods are not sufficient for all women, there is a need for alternative modalities to accelerate the resumption of bowel functioning. In the Paula Method exercise group, time to first flatus passage occurred significantly sooner compared with the control group. Time to first defecation was earlier in the Paula Method exercise group but this difference did not reach statistical significance. Along with gum chewing, Paula Method exercises can be part of a simple and inexpensive GI activation strategy post CD. Further research should be performed using these exercises post other operative procedures.

Can simple perioperative measures improve quality of recovery following ambulatory laparoscopic surgery in females? An open prospective randomised cohort study, comparing nutritional preoperative drink and chewing gum during recovery to standard care

One major goal in modern perioperative anaesthesia care is to facilitate a rapid, yet safe recovery process, with focus on improving time to regained consciousness and subsequent resuming of activities of daily living. Laparoscopic cholecystectomy and gynaecological laparoscopy are a “high volume” procedure commonly performed in young females expecting rapid resumption of health.

The aim of this study was to assess whether it was possible to improve patients’ self-assessed quality of recovery in female patient undergoing laparoscopic cholecystectomy by simple perioperative measures in the form of a preoperative 200 ml nutritional drink and chewing gum during early recovery.

Methods

Patients were randomised to an active group receiving the intervention, and controls provided with standard care only. Patients were followed by questionnaire interviews preoperatively and at 2, 24 and 48 h after surgery. The Quality of Recovery scale (QoR) 15 items and 5 additional questions around gastro-intestinal symptoms were self-assessed by patients at each occasion.

Result

Seventy-three ASA 1–2 female patients’ undergoing elective laparoscopic surgery were included, surgery and anaesthesia was uneventful. The QoR score was significantly higher both at 24 and 48 h, 113 SD 20 vs 101 SD 25 (p = 0.026) and 123 SD 13 vs 111 SD 13 (p = 0.006) in the active group of patients as compared to controls.

Conclusion

Simply providing 200 ml nutritional preoperative drink and chewing gum during recovery was found effective, improving patients assessed quality of recovery.

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One major goal in modern perioperative anaesthesia care is to facilitate a rapid, yet safe recovery process.

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Simply providing 200 ml nutritional preoperative drink and chewing gum during recovery was found effective, improving patients self-assessed quality of recovery.

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Quality of recovery, assessed by a multi dimensional tool (QoR15), in females after laparoscopic surgery is still not complete 48 h after surgery.

Chewing Gum for Intestinal Function Recovery after Colorectal Cancer Surgery: A Systematic Review and Meta-Analysis

Background

This meta-analysis was performed to assess the efficacy and safety of chewing gum in intestinal function recovery after colorectal cancer surgery.

Methods

A systematic search was conducted in PubMed, Embase, Science Direct, and Cochrane library for relevant randomized controlled trials (RCTs) published until April 2017. Summary risk ratios or weighted mean differences with 95% confidence intervals were used for continuous and dichotomous outcomes, respectively.

Results

17 RCTs with a total number of 1845 patients were included. Gum chewing following colorectal cancer surgery significantly reduced the time to first passage of flatus (WMD −0.55; 95% CI −0.94 to −0.16; P = 0.006), first bowel movement (WMD −0.60; 95% CI −0.87 to −0.33; P < 0.0001), start feeding (WMD −1.32; 95% CI −2.18 to −0.46; P = 0.003), and the length of postoperative hospital stay (WMD −0.88; 95% CI −1.59 to −0.17; P = 0.01), but no obvious differences were found in postoperative nausea, vomiting, abdominal distention, pneumonia, and mortality, which were consistent with the findings of intention to treat analysis.

Conclusions

Chewing gum could accelerate the recovery of intestinal function after colorectal cancer surgery. However, it confers no advantage in postoperative clinical complications. Further large-scale and high-quality RCTs should be conducted to confirm these results.

Chewing gum for intestinal function recovery after caesarean section: a systematic review and meta-analysis

Background

Gum chewing has been reported to enhance the intestinal function recovery after caesarean section, current perspectives and practice guidelines vary widely on the use of gum chewing, more studies on the role of gum chewing after caesarean section are needed.

Methods

We performed a comprehensive, systematic meta-analysis of randomized controlled trials (RCTs) on the efficacy of gum chewing after caesarean section. Studies were identified by searching EMBASE et al database (until June 30, 2016). Summary odd ratios or weighted mean differences with 95% confidence intervals were calculated for each outcome with fixed- or random-effects model.

Results

Ten RCTs with a total of 1659 women were included in our meta-analysis. Gum chewing provided significant benefits in reducing the time to first passage of flatus, first defecation, first bowel sound, first bowel movement and the length of hospital stay, but not in the time to first feeling of hunger.

Conclusions

Gun chewing hastens the intestinal function recovery after caesarean section and offers a safe and inexpensive option. High-quality and larger-scale RCTs are still warranted to clarify the role of gum chewing in intestinal function recovery after caesarean section.

Sham Feeding with Chewing Gum in Early Stage of Acute Pancreatitis: A Randomized Clinical Trial

Background

The correlation between sham feeding and acute pancreatitis (AP) has only been examined in limited studies. We aimed to investigate the efficacy and safety of sham feeding in the early stage of AP.

Material/Methods

A randomized controlled clinical trial was performed. Equal groups of AP patients were recruited. Patients in the sham feeding group received chewing gum 4 times a day after admission. All patients in the trial received standard treatment consistent with the guidelines for AP. The primary outcomes were mortality, length of stay (LOS), and medical expenses. Secondary outcomes were the incidence of complications and other adverse events, return of gastrointestinal function, the details of enteral nutrition and intra-abdominal pressure.

Results

From May 2014 to December 2015, a total of 204 patients were recruited. The LOS and hospital costs in the sham feeding group were reduced, although mortality was equivalent between groups. The return of gastrointestinal function occurred earlier in the sham feeding group, with no complications related to gum chewing.

Conclusions

Sham feeding with chewing gum is safe and efficacious in the early stage of AP.

Chewing gum for enhancing early recovery of bowel function after caesarean section

BACKGROUND

Caesarean sections (CS) are the most frequent major surgery in the world. A transient impairment of bowel motility is expected after CS. Although this usually resolves spontaneously within a few days, it can cause considerable discomfort, require symptomatic medication and delay hospital discharge, thus increasing costs. Chewing gum in the immediate postoperative period is a simple intervention that may be effective in enhancing recovery of bowel function in other types of abdominal surgeries.

OBJECTIVES

To assess the effects of chewing gum to reduce the duration of postoperative ileus and to enhance postoperative recovery after a CS.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 June 2016), LILACs (20 June 2016), ClinicalTrials.gov (20 June 2016), WHO International Clinical Trials Registry Platform (ICTRP) (20 June 2016) and the reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled trials comparing chewing gum versus usual care, for women in the first 24 hours after a CS. We included studies published in abstract form only.Quasi-randomised, cross-over or cluster-randomised trials were not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies for inclusion, extracted data and assessed the risk of bias following standard Cochrane methods. We present dichotomous outcome results as risk ratio (RR) with 95% confidence intervals (CI) and continuous outcome results as mean differences (MD) and 95% CI. We pooled the results of similar studies using a random-effects model in case of important heterogeneity. We used the GRADE approach to assess the overall quality of evidence.

MAIN RESULTS

We included 17 randomised trials (3149 participants) conducted in nine different countries. Seven studies (1325 women) recruited exclusively women undergoing elective CS and five studies (833 women) only included women having a primary CS. Ten studies (1731 women) used conventional feeding protocols (nil by mouth until the return of intestinal function). The gum-chewing regimen varied among studies, in relation to its initiation (immediately after CS, up to 12 hours later), duration of each session (from 15 to 60 minutes) and number of sessions per day (three to more than six). All the studies were classified as having a high risk of bias due to the nature of the intervention, women could not be blinded and most of the outcomes were self-reported.Primary outcomes of this review: for the women that chewed gum, the time to passage of first flatus was seven hours shorter than those women in the 'usual care' control group (MD -7.09 hours, 95% CI -9.27 to -4.91 hours; 2399 women; 13 studies; random-effects Tau² = 14.63, I² = 95%, very low-quality evidence). This effect was consistent in all subgroup analyses (primary and repeat CS, time spent chewing gum per day, early and conventional feeding protocols, elective and non-elective CS and time after CS when gum-chewing was initiated). The rate of ileus was on average over 60% lower in the chewing-gum group compared to the control (RR 0.39, 95% CI 0.19 to 0.80; 1139 participants; four studies; I² = 39%, low-quality evidence). Tolerance to gum-chewing appeared to be high. Three women in one study complained about the chewing gum (but no further information was provided) and none of the studies reported adverse effects (eight studies, 925 women, low-quality evidence).Secondary outcomes of this review: the time to passage of faeces occurred on average nine hours earlier in the intervention group (MD -9.22 hours, 95% CI -11.49 to -6.95 hours; 2016 participants; 11 studies; random-effects Tau² = 12.53, I² = 93%, very low-quality evidence). The average duration of hospital stay was shorter in the intervention compared to the control group (MD -0.36 days, 95% CI -0.53 to -0.18 days; 1489 participants; seven studies; random-effects Tau² = 0.04, I² = 92%). The first intestinal sounds were heard earlier in the intervention than in the control group (MD -4.56 hours, 95% CI -6.18 to -2.93 hours; 1729 participants; nine studies; random-effects Tau² = 5.41, I² = 96%). None of the studies assessed women's satisfaction in relation to having to chew gum. The need for analgesia or antiemetic agents did not differ between the intervention and control groups (average RR 0.50, 95% CI 0.12 to 2.13; 726 participants; three studies; random-effects Tau² = 0.79, I² = 69%).

AUTHORS' CONCLUSIONS

This review found 17 randomised controlled trials (involving 3149 women). We downgraded the quality of the evidence for time to first passage of flatus and of faeces and for adverse effects/intolerance to gum chewing because of the high risk of bias of the studies (due to lack of blinding and self-report). For time to first flatus and faeces, we downgraded the quality of the evidence further because of the high heterogeneity in these meta-analyses and the potential for publication bias based on the visual inspection of the funnel plots. The quality of the evidence for adverse effects/tolerance to gum chewing and for ileus was downgraded because of the small number of events. The quality of the evidence for ileus was further downgraded due to the unclear risk of bias for the assessors evaluating this outcome.The available evidence suggests that gum chewing in the immediate postoperative period after a CS is a well tolerated intervention that enhances early recovery of bowel function. However the overall quality of the evidence is very low to low.Further research is necessary to establish the optimal regimen of gum-chewing (initiation, number and duration of sessions per day) to enhance bowel function recovery and to assess potential adverse effects of and women's satisfaction with this intervention. New studies also need to assess the compliance of the participants to the recommended gum-chewing instructions. Future large, well designed and conducted studies, with better methodological and reporting quality, will help to inform future updates of this review and enhance the body of evidence for this intervention.