Accelerated surgical rehabilitation recommends the oral intake of clear fluids up to ≤ 400 mL 2 h before surgery [12]. Clinicians prioritize safety and may not always adhere to this preoperative fluid intake recommendation. Our study revealed that the majority of patients refrained from drinking water from the evening before surgery until the following day. Some patients consumed 400 mL of clear fluid at 06:00 a.m. on the day of the operation. On average, patients included in the study abstained from drinking for approximately 11.57 ± 2.95 h.
The ERAS management concept recommends goal-oriented or restricted fluid infusion during surgery, which significantly reduces the total intraoperative fluid volume in patients [13–14]. In our collected patients, the average duration of anesthesia was 126.82 ± 38.18 min, with an intraoperative infusion volume of 321.28 ± 113.71 mL. Despite these anesthesia management strategies, they may not fully meet the fluid needs of patients who have refrained from consuming water for a long time. As a result, patients in the day surgery center frequently present with dry throats and a strong desire to drink water upon entering the PACU after recovering from anesthesia.
In this study, the time elapsed from the recovery of general anesthesia to the commencement of water intake averaged 31.77 ± 11.44 min. Various studies have reported different recommendations regarding the timing of water intake. Mercan proposed that children could drink water 1 h after surgery [5], whereas Yin’s study reported a first water intake time of 0.29 ± 0.14 h [15], which was similar to our results.
Before drinking water, patients are required to undergo a safety assessment, which we do in conjunction with the Safety Protocol for Thirst Management (SPTM) [8] and the postanesthetic exit scoring system [16]. The assessments included good recovery of consciousness, recovery of respiratory protection mechanisms (coughing and swallowing), and absence of postoperative nausea and vomiting. The assessment of not only the pharyngeal reflexes and swallowing function was emphasized but also postoperative bleeding from the surgical site, potential postoperative airway risks, and secondary surgical risk assessment. This study was conducted to ensure patient safety and provides a valuable reference for future clinical applications.
Studies have reported concerns regarding complications such as vomiting and accidental inhalation following early water consumption. Most studies recommend restricting the water supply in the PACU. In this study, patients were divided into four groups based on the amount of water they consumed. There was no statistically significant difference in the incidence of nausea and vomiting between the groups (p = 0.289). Patients did not show a greater tendency for complications such as choking, coughing, nausea, or vomiting despite consuming excessive amounts of water. For instance, 19.23% (11/52) of patients in Group C drank more than 400 ml of water in a single sitting position, with the highest intake recorded at 750 ml. Remarkably, no instances of nausea or vomiting were reported in Group C due to increased water intake. Only one patient from the consumption group vomited after returning to the ward, resulting in an overall occurrence rate of 0.67%, which was significantly lower than that reported in previous studies [17–18]. In contrast, Group D included two cases of coughing and vomiting in patients who drank water after returning to the ward. All three patients underwent goiter resection. The primary reason for vomiting was not poor gastrointestinal function recovery but rather throat stimulation associated with this type of surgery. After complete metabolism and clearance of narcotic analgesic drugs during surgery, patients often experience significant swallowing pain. This made them prone to coughing and, subsequently, vomiting when drinking too much or too quickly. By adjusting the drinking water speed and the volume of water consumed in a single instance or by utilizing oral analgesics, these patients can effectively reduce their discomfort and minimize the risk of choking-cough-induced vomiting. The patients included in the study did not experience severe vomiting or accidental inhalation during their hospitalization.
Proper positioning during drinking is crucial, as adjusting posture correctly can enhance patient comfort, alleviate tension, and effectively reduce the likelihood of nausea and vomiting. By aligning the head position with physiological norms, we can alleviate strain on soft tissues such as neck muscle ligaments. This decrease in muscle tension and neck pain also helps reduce vertebral artery compression and distortion, thus preventing cerebral ischemia, lowering intracranial pressure, and minimizing the chances of headaches, nausea, and vomiting [19]. Moreover, adjusting the head position displaces the upper abdominal organs outward, relaxes abdominal muscles, stimulates the gastrointestinal tract, and can dampen certain vagal impulses responsible for nausea and vomiting. Therefore, it is important to gradually modify the head elevation to ensure a comfortable drinking posture for each patient. In our research, the head of the bed was raised at a 19-degree angle. However, the degree of bed inclination for head elevation is influenced by the surgical area. For instance, in regard to wounds from thyroid surgery in the neck or laparoscopic surgery in the upper abdomen, excessive bed elevation may subject the wound to pressure, causing discomfort and pain. Conversely, patients who are recovering from surgery for skin tumors or limbs may find a slightly reclined drinking position more suitable. Hence, determining whether to elevate the head of the bed and to what extent should be based on the individual patient's comfort level.
Early drinking water had a positive effect on several aspects of patient well-being, including stabilizing the patient’s mood, alleviating postoperative tension and anxiety, effectively relieving their thirst, improving the dryness and discomfort in their throats, and reducing postoperative wound pain. Notably, there was no linear correlation between the reduction in other scores and the volume of water consumed, and no significant differences were found among groups with varying water intake amounts (p > 0.05). Even a small amount of warm water given orally was equally effective at achieving the desired therapeutic effect. In essence, different patients consumed varying quantities of water, but the treatment goal remained consistent. Drinking water-stimulated gland secretion effectively alleviated dry throat discomfort, and postoperative patients were satisfied with the early drinking water treatment strategy.
This study employed ultrasound to monitor the movement of the gastric antrum both before and after drinking water. These changes in gastric antrum movement serve as an indicator of gastrointestinal function recovery. Research has demonstrated that a complex bidirectional relationship exists between the brain and the gut. Negative emotions, such as anxiety or fear, can have adverse effects on intestinal function [20–21]. Patients who are recovering from general anesthesia experience uncertain surgical outcomes, unfamiliar surroundings, pain, thirst, hunger, and other discomfort, which can lead to negative emotions. These emotions directly affect gastrointestinal motility. We observed that most patients had relatively static stomachs before drinking water, with a median gastric antrum MI of 0.00 (0, 0.05). However, after drinking water, patients’ moods stabilized, and they felt happier and more at ease. Drinking water also directly stimulates the gastric wall, promoting gastric peristalsis and gastric secretion through this dual effect. Ultrasound revealed a significant increase in gastric antrum movement, with the median gastric antrum MI after drinking water increased to 1.61 (0,3.66).
This study revealed a positive correlation between antral motility and water intake (Fig. 3). The more water patients consumed, the more active their gastrointestinal peristalsis became. The median antral MI of patients who consumed 1–2 ml/kg water was 1.78 (0.45–4.18). The median antral MI of patients who consumed > 2 ml/kg water was 2.35 (0.59–3.77), which was significantly greater than that of patients who consumed < 1 ml/kg water. The linear correlation between water intake and the antral MI, as well as any potential capping effect, is an aspect that has not been addressed in the literature, thus warranting further research.
We can conceptualize a scenario in which after general anesthesia resuscitation, patients are free to drink unlimited amounts of water while in the PACU; however, the amount of water consumed is closely related to the surgical site and sex. Patients who underwent thyroid surgery tended to consume less water at a relatively slower pace, as swallowing could cause discomfort or pain at the surgical site. In contrast, those undergoing superficial or limb surgeries demonstrated a preference for larger quantities and a quicker pace of water intake. Furthermore, male patients consistently expressed greater demands for water than female patients did, leading to greater water intake [22]. The amount of water consumed was also closely related to the patient’s past drinking habits [23]. Patients who habitually consumed more water daily also exhibited greater desire and capacity for post-surgery water consumption.
Drinking large amounts of water does not increase the incidence of nausea and vomiting, but fatal injuries with vomiting aspiration cannot be ruled out. For the sake of clinical safety and rationality, it is still recommended to set a maximum drinking water volume. This not only alleviates the concerns of medical staff but also meets patients' need for drinking water while achieving the same therapeutic effects. A reasonable drinking water volume is suggested to be ≤ 3 ml/kg of body weight or to maintain the total amount within 300 ml.
As with any research, it is important to consider specific constraints. For instance, the study encompasses various surgical procedures, and the quantity of water intake is intricately linked to the surgical location and procedure type. Post-anesthesia care unit (PACU) staff members face limitations and are unable to perform pre-drinking evaluations promptly based on the patient's physiological recovery, potentially leading to significant variations in the time gap for water consumption.