ABSTRACT
Objective To investigate the clinical effects of four different bowel preparation methods for colonoscopy.Methods 620 patients examined by coloscopy were randomized into four groups (group A,B,C and D),with each group in 155 cases.Group A received magnesium sulfate.Group B received compound polyethylene glycol.Group C received magnesium sulfate combined with simethicone.Group D received compound polyethylene glycol combined with simethicone.The quality and influencing factors,the detection of polyps and adverse events were compared between the four groups.Results The good bowel cleaning rate of group A,B,C and D were respectively 84.52％,91.61％,85.81％ and 94.19％.The good bowel cleaning rates of group A and C were higher than those of group B and D (x2 =4.32,P ＜ 0.05;x2 =7.63,P ＜ 0.05;x2 =4.10,P ＜ 0.05;x2 =6.06,P ＜ 0.05.).The bubble free rate of group A,B,C and D were 86.45 ％,87.74％,92.26％ and 90.96％.The bubble free rates of group C and D were higher than those of group A and B (x2 =4.17,P ＜ 0.05;x2 =4.76,P ＜ 0.05;x2 =5.02,P ＜ 0.05;x2 =4.23,P ＜ 0.05).The polyp detection rates of group A,B,C and D were 35.4％,36.8％,51.6％ and 54.2％.Group C and D showed higher quality of foam eliminating and detection rate of polyps as compared with group A and B (x2 =8.24,P ＜0.05;x2 =11.04,P ＜0.05;x2 =6.95,P ＜0.05;x2 =9.53,P ＜0.05).The incidence of adverse reactions of group A and C (21.3％ and 19.4％) were higher than group B and D (7.8％ and 6.5％) (x2 =11.86,P＜0.05;x2 =14.95,P ＜0.05;x2 =9.18,P ＜0.05;x2 =11.95,P ＜0.05).The frequency of colonoscopy,constipation,medication and examination time interval,bowel preparation methods and adverse events were the the influ ence factors of bowel preparation.Conclusion The quality of bowel preparation of compound polyethylene glycol electrolyte powder is better than magnesium sulfate with high security.Treatment of combination with simethicone can improve bowel preparation quality.Many factors can affect bowel preparation,which need to be paid attention to.