Table 1 Baseline characteristics of included studies

Yin et al. (2014) [15]

1000

500, early drinking;

500, 4 h post-surgery

General anaesthesia

Delayed gastric emptying and existing gastrointestinal diseases; facial, oropharyngeal and throat surgery; impaired mental state; difficulty swallowing; gastrointestinal surgery; neurosurgery; thoracic surgery

Non-gastrointestinal general anaesthesia

After assessment, early water was given with a volume limit of 0.5 mL/kg.

Drinking water 4 h post-surgery

early drinking: 22/488 (5%)

Regular: 20/495 (4%)

Not reported

early drinking: 37/488 (8%)

Regular: 32/495 (6%)

early drinking: 46.27 ± 20.23

Regular: 61.09 ± 20.11

Not reported

Not reported

Wu et al. (2019) [14]

1735

867, early drinking;

868, 4 h post-surgery

General anaesthesia

Intestinal obstruction, dysphagia, diabetes, history of PONV, or American College of Anesthesiologists Class III or higher constitution

Laparoscopic cholecystectomy

After assessment, early water was given, and the total water volume was limited to 3 mL/kg.

Drinking water 4 h after surgery

early drinking:14/867(2%)

Regular:31/868(4%)

Not reported

Early drinking: 23/867 (3%)

Regular: 46/868(5%)

early drinking:37.51 ± 28.44

Regular:61.31 ± 33.21

Not reported

Not reported

Zhang et al. (2020) [19]

130

65, early drinking;

65, regular drinking water

General anaesthesia

Respiratory tract infection before surgery; a history of facial, oropharyngeal and laryngeal surgery; a history of dysphagia and gastrointestinal disorders; vertigo

Laparoscopic tubal plastic surgery

After assessment, early water intervention was administered, and the maximum water intake was 50 mL.

Regular drinking water

Not reported

Not reported

Not reported

Early drinking: 25/658 (38%)

Regular: 38/58 (66%)

Early drinking: 12.00 ± 1.22

Regular: 15.10 ± 1.05

Not reported

Yun et al. (2020) [17]

268

134, early drinking; 

134, regular drinking water

General anaesthesia

Mental illness or other complications; impaired speech and communication and use of sedatives and analgesics within 24 h; history of intestinal obstruction, dysphagia, diabetes, postoperative nausea and vomiting, inability to complete the assessment of various scales, or ASA level III or above

Thoracoscopic lobectomy

Early water intervention was performed after assessment, with no more than 3 mL for the first injection, 5–10 mL for each injection, and a total of no more than 2 mL/kg.

Regular drinking water

Early drinking:3/134 (2%)

Regular: 2/134 (2%)

Not reported

Early drinking: 4/134 (3%)

Regular: 5/134 (4%)

Early drinking: 29.4 ± 29.6

Regular: 63.3 ± 38.2

Not reported

Not reported

Peng et al. (2019) [20]

1000

500, early drinking;

500, regular drinking water

General anaesthesia

Gastrointestinal dysfunction; bowel and urine dysfunction; in-dwelling gastric tube; combined with digestive tract obstruction, digestive tract perforation, neurosurgery and oral surgery

Tracheal intubation under general anaesthesia

After assessment, 20 mL of warm sterilised water was given early, and the interval between two drinks exceeded 2 h.

Regular drinking water

Not reported

Early drinking: 19/500 (4%)

Regular: 23/500 (5%)

Not reported

Not reported

Early drinking: 18.24 ± 7.79

Regular: 25.72 ± 10.33

Early drinking: 55.40 ± 13.96

Regular: 60.89 ± 13.55

Ma et al. (2019) [22]

80

40, early drinking;

40, regular drinking water

General anaesthesia

Gastrointestinal diseases; nausea and vomiting before the first intervention

Transnasal sphenoidal approach for pituitary tumour resection

Warm boiled water (10 mL) was given every 0.5 min within 1–2 h post-surgery, with no more than 0.5 mL/kg warm boiled water provided every 0.5 h within 3–6 h post-surgery.

Regular drinking water

Early drinking: 3/40 (8%)

Regular: 5/40 (13%)

Not reported

Early drinking: 5/40(13%)

Regular: 7/40 (18%)

Not reported

Early drinking: 16.53 ± 2.78

Regular: 19.70 ± 3.39

Not reported

Lv et al. (2015) [21]

200

100, early drinking;

100, regular drinking water

General anaesthesia

Oropharyngeal surgery; difficulty swallowing; airway obstruction

General anaesthesia

A small amount of water was given at the early stage, 5 mL 0.9% NaCl was given every 5 min, and the total amount should not exceed 0.5 mL/kg body weight.

Regular drinking water

Not reported

Early drinking: 4/100 (4%)

Regular: 6/100 (6%)

Not reported

Early drinking: 1.39 ± 1.2

Regular: 7.51 ± 1.48

Not reported

Not reported

Lv et al. (2022) [16]

200

100, early drinking;

100, regular drinking water

General anaesthesia

Mallampati classification < III; mental disorders; abnormal digestive tract function; other diseases affecting observation and assessment of digestive tract function

Arthroscopic cruciate ligament reconstruction of the knee joint

Early stepped intervention with a small amount of drinking water was performed, and 37℃ normal saline was given once every 15 min, 10 mL for each of the first three times, 15 mL for each of the next three times, and 20 mL for each of the following three times.

Regular drinking water

Not reported

Not reported

Not reported

Early drinking: 6.71 ± 1.32

Regular: 8.63 ± 1.72

Early drinking: 17.53 ± 7.28

Regular: 23.67 ± 9.67

Early drinking: 50.37 ± 12.65

Regular: 59.86 ± 12.37

Gu et al. (2020) [18]

400

200, early drinking;

200, regular drinking water

General anaesthesia

Oral, nasal and pharyngeal operations; nausea and vomiting; cognitive impairment and severe complications

Non-gastrointestinal surgery

Early water intervention, the first slow injection of 5 mL, 10 min later, can be repeated once.

Regular drinking water

Not reported

Not reported

Not reported

Early drinking: 4.62 ± 1.65

Regular: 5.07 ± 2.14

Not reported

Not reported

Zhang et al. (2021) [23]

118

59, early drinking

59, regular drinking water

Regular drinking water

History of gastrointestinal disease or surgery; gastrointestinal tract or strict fasting after surgery; severe adverse anaesthetic reactions; unable to match the study

Laparoscopic surgery for gynaecological malignancies

After assessment, early drinking water was given, and a small amount of warm water was slowly dripped from the corners of the patient’s mouth using a syringe or a graduated spoon. The initial amount was 5 mL each time, and the upper limit was 100 mL per hour.

Regular drinking water

Not reported

Not reported

Not reported

Early drinking: 2.06 ± 0.64

Regular: 5.32 ± 1.51

Early drinking: 14.81 ± 3.67

Regular: 22.69 ± 6.71

Early drinking: 54.16 ± 9.11

Regular: 58.72 ± 10.35