Clear fluids three hours before surgery do not affect the gastric fluid contents of children. [Possibility of rice porridge for preoperative feeding in children]. Shortened preanesthetic fasting interval in pediatric cardiac surgical patients. Preoperative drinking does not affect gastric contents. Ingestion of liquids compared with preoperative fasting in pediatric outpatients. The effect of pre-operative oral fluids on morbidity following anaesthesia for minor surgery. Effects of 2-, 4- and 12-hour fasting intervals on preoperative gastric fluid pH and volume, and plasma glucose and lipid homeostasis in children. Effect of preoperative oral fluids on gastric volume and pH in postpartum patients. Ingestion of clear fluids is safe for adolescents up to 3 h before anaesthesia. Allowing pre-operative patients to drink: effects on patients' safety and comfort of unlimited oral water until 2 hours before anaesthesia. The effect of different pre-operative feeding regimens on plasma glucose and gastric volume and pH in infancy. Immediate postoperative oral hydration after caesarean section. [The volume and pH of gastric fluid in elective surgical patients after preoperative oral fluid intake]. Gastric pH and volume after oral fluids in the postpartum patient. Effects of duration of fasting on gastric fluid pH and volume in healthy children. Gastric residual volume in infants and children following a 3-hour fast. Fluid deprivation before operation. The effect of a small drink. Oral fluids prior to day surgery. The effect of shortening the pre-operative fluid fast on postoperative morbidity. The effect of pre-operative intake of oral water and ranitidine on gastric fluid volume and pH in children undergoing elective surgery.
This prospective, randomized, single-blind study of 121 healthy children aged 2 to 12 yr investigated the effect of clear fluids on gastric contents. Gastric fluid volume and pH were measured immediately following the induction of general anaesthesia and were not significantly affected by the ingestion of unlimited clear fluids up to three hours preoperatively. After a prolonged fast (mean fast 14 hr), gastric fluid volume was 0.39 +/- 0.37 ml.kg-1 and gastric pH was 1.7 +/- 0.4; after unlimited clear fluids (203 +/- 109 ml) up to three hours before surgery gastric fluid volume was 0.34 +/- 0.28 ml.kg-1 and gastric pH was 1.8 +/- 0.7 (mean +/- SD). Gastric fluid volume (ml.kg-1) increased in both the control and study groups as age increased, P less than 0.005. It is concluded that drinking clear fluid up to three hours before scheduled surgery does not have a measurable effect on gastric volume and pH of healthy children of ages 2 to 12 yr. To determine the effect of rice porridge feeding before elective surgery on preoperative gastric fluid pH, volume and starvation, a prospective study was undertaken in pediatric patients. Twenty healthy children ranged in age from 5 to 12 years were allocated randomly to either a fasted or rice porridge group. The children of fasted group (control group) were allowed to take solid food until midnight before the operation. The rice porridge group (study group) patients received a small amount of rice porridge 5 hours 30 minutes before the induction of anesthesia. The patients of both groups were permitted to take clear fluid until 5 hours before the induction of anesthesia. After the induction of anesthesia, gastric fluid was aspirated through an orogastric tube. The mean gastric fluid volume was 0.43 +/- 0.32 ml.kg-1 in the control group and 0.5 +/- 0.6 ml.kg-1 in the study group. The mean gastric fluid pH was 1.43 +/- 0.27 ml.kg-1 in the control group and 1.89 +/- 0.75 ml.kg-1 in the study group. There were no significant differences between the two groups concerning the gastric fluid volume and pH. The patient of the study group complained of less hunger. Preoperative rice porridge feeding is a possible preoperative feeding for pediatric patients. The recent liberalization of preoperative feeding orders in healthy pediatric outpatients prompts the question of whether this applies to children about to have cardiac surgery. The authors compared gastric fluid volume and pH in two groups of children undergoing elective cardiac surgery, one of which was not only permitted ad libitum clear liquids but was mandated to drink clear liquids 2-3 h before induction of anesthesia (study group). The other group followed routine inpatient preoperative fasting orders (control group). The study group (n = 44) averaged 3.1 +/- 4.1 yr and weighed 15.3 +/- 16.3 kg; the control group averaged 3.3 +/- 3.9 yr and weighed 14.3 +/- 12.1 kg (P = 0.82, 0.73, respectively). Aspiration of residual gastric fluid volume was attempted in all patients after induction of anesthesia. Gastric fluid volume averaged 0.6 +/- 0.9 mL/kg in the study group and 0.4 +/- 0.6 mL/kg in the control group (P = 0.13). Of the study patients, 41% had a measured gastric volume greater than or equal to 0.4 mL/kg compared with 32% of the control patients (P = 0.50). Of the 42 patients who had residual gastric fluid aspirated, pH determinations were completed on 37 aspirates; of these 19 of 20 (95%) in the study group and 14 of 17 (82%) in the control group had a gastric pH less than or equal to 2.5. Using a linear analogue scale, parents rated children in the study group to be more comfortable, less hungry, and less thirsty compared with the control patients (P = 0.004, 0.002, 0.0001, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) We have compared the effect of allowing free clear fluids until the time of oral premedication with conventional preoperative fasting. In a prospective, randomized trial, the residual volume and pH of gastric contents after induction of anaesthesia were measured in 100 elective surgical patients allocated randomly to a group in whom the intake of free clear fluids up to the time of premedication was measured (mean 388 ml in 6 h before surgery) or a control group who were fasted for 6 h. Preoperative drinking did not affect either mean (SD) residual gastric volume (22 (21) ml in the study group vs 19 (16) ml in the control group) or pH (study group 2.64 (1.57) vs control group 2.26 (1.45)). The study group experienced less preoperative thirst. Problems with aspiration or regurgitation were not encountered. We believe that allowing elective surgical patients to drink clear fluids until 2 h before anaesthesia may enhance patient comfort without compromising safety. The preoperative fast is often an unpleasant preoperative experience that might be alleviated by allowing children to drink clear liquids. The authors compared gastric fluid volume and pH in two groups of children, one of whom was permitted clear liquids until 2 h before surgery (study group) and the other followed routine preoperative fasting orders (control group). The study group was not limited in the quantity of clear liquid allowed with the exception that the last intake prior to surgery was limited to 8 ounces. The study group (n = 53) averaged 5.9 +/- 5 yr and weighed 23.6 +/- 17 kg, while the control group averaged 7.3 +/- 4.6 yr and weighed 29 +/- 17.7 kg (P = NS). Gastric contents were aspirated following induction of anesthesia. Gastric fluid volume averaged 0.44 +/- 0.51 ml/kg for study group and 0.57 +/- 0.51 ml/kg in the control group (P = 0.12). Of the study patients, 48% had a measured gastric fluid volume greater than or equal to 0.4 ml/kg compared with 58% of the control patients (P = 0.77). Eighty three patients had sufficient gastric fluid for pH determination; of these 34/35 (97%) in the study group and 44/48 (92%) in the control group had a gastric fluid pH less than or equal to 2.5. Using a linear analog scale parents rated the children in the study group to be less irritable (P less than 0.001) and to have had a better overall preoperative experience (P less than 0.01) compared with the control patients.(ABSTRACT TRUNCATED AT 250 WORDS) Postoperative morbidity and serum osmolality were studied in 46 patients who were encouraged to drink water until 3 h pre-operatively and 49 receiving the normal fasting regimen prior to minor surgery. There was significantly less thirst in the postoperative period in those patients allowed to drink and subjectively better recovery than after previous anaesthesia. There was no morbidity from ingestion of up to 11 of water 2.5 h pre-operatively. Although there was only a moderate improvement in postoperative recovery we feel that allowing patients to drink water pre-operatively improves patient comfort, especially since patients may have to fast for much longer than guidelines recommend, simply because of the traditional organisation of operating lists. We evaluated 105 randomly-selected unpremedicated children aged 1-14 years to determine the effects of a 2-, 4- and 12-h preoperative fasting interval on the preoperative gastric fluid pH and volume, and plasma glucose and lipid homeostasis. Each child undergoing elective surgery ingested a large volume (approximately 10 ml/kg b.w.) of apple juice and then fasted for 2, 4 or 12 h before the estimated induction of anaesthesia. After induction of anaesthesia, gastric fluid was aspirated through a large-bore, multiorifice orogastric tube. Plasma concentrations of glucose, total ketone bodies, non-esterified fatty acid (NEFA), triglycerides, and cortisol were measured at the time of induction to evaluate the fasting interval effects on preoperative plasma glucose and lipid homeostasis. There were no significant differences between the three groups in either gastric fluid volume or pH. In addition, there were no significant differences between the groups with respect to the proportion with a pH < 2.5 and volume > 0.4 ml/kg b.w. Neither plasma concentrations of glucose, triglycerides, nor cortisol at the time of anaesthetic induction differed between the three groups. Both 4 and 12 h nil per os (NPO) caused an increase in lipolysis, which was presumably a compensatory mechanism to maintain normoglycaemia. The plasma NEFA and total ketone bodies concentrations were therefore significantly higher in these two fasting intervals than in 2 h NPO. These data suggest that a 2-h NPO, after a large volume of ingested apple juice, may offer additional benefits by preventing an increase in lipolysis during the fasting interval without either increasing the volume of gastric fluid or decreasing the gastric pH.(ABSTRACT TRUNCATED AT 250 WORDS) The effect of preoperative oral fluids to postpartum patients on the gastric volume and pH was compared with normally fasting postpartum and non-pregnant patients undergoing sterilisation. Forty consecutive postpartum patients and twenty non-pregnant patients scheduled for sterilisation procedure were selected for the study. All patients were fasted overnight. Twenty postpartum patients were randomly allocated to receive 150 ml of plain water two and half hours before surgery (Group 1), while the remaining postpartum patients (Group 2) and non-pregnant patients (Group 3) continued their overnight fast as usual. After induction of anesthesia, gastric volume and pH was measured in all the patients. The mean gastric volume was found to be 21.9 +/- 8.49 ml in Group 1, 22.55 +/- 8.30 ml in Group 2 and 22.65 +/- 8.17 ml in Group 3. The mean pH was found to be 2.21 +/- 0.98 in Group 1, 2.18 +/- 0.88 in Group 2 and 2.12 +/- 1.02 in Group 3. The difference in the volume and pH in all the three groups was statistically insignificant. The difference in the incidence of patients with combined high risk factors of acid aspiration syndrome (gastric fluid volume > 25 ml and pH < 2.5) among the three groups was also insignificant. The authors conclude that ingestion of 150 ml of plain water approximately two and half hours before scheduled time of surgery in overnight fasted postpartum patients does not increase the risk of aspiration syndrome. We have studied the effect of ingestion of unlimited clear fluids by adolescents up to 3 h before anaesthesia to determine the effect this fluid ingestion would have on thirst, hunger and gastric contents at induction of anaesthesia. We studied prospectively 152 adolescents (ages 13-19 yr) undergoing elective surgery. Fifty percent of the patients had nothing by mouth after midnight. The other 50% were instructed to ingest unlimited clear fluids up to 3 h before surgery. On arrival in the operating room, subjects were asked to assess thirst and hunger with a linear analogue scale of 0-10 (0 corresponding to no thirst or no hunger). After induction of anaesthesia, gastric contents were aspirated via a 16-French gauge orogastric tube. Gastric fluid volume (GV) was measured with a syringe and gastric pH (GpH) was assessed with Merck pH strips. GV, GpH and subject hunger were unaffected by ingestion of clear fluids. Subject thirst was reduced by clear fluids. It is concluded that unlimited clear fluid ingestion by healthy adolescents up to 3 h before operation decreases thirst and does not affect gastric contents. The effect of allowing patients unlimited access to oral water in the time up until 2 h pre-operatively was the subject of a randomised, blind, controlled trial. No effect was seen on gastric volume or pH, or on plasma osmolality, and allowing water pre-operatively was associated with a reduction in anxiety in the anaesthetic room. The effects of four different pre-operative feeding regimens were studied in 123 children below the age of one year presenting for surgery. Plasma glucose concentrations, blood acid-base values, gastric volume and gastric pH were measured before and after induction of anaesthesia. No patient was found to be hypoglycaemic and there were no significant differences in plasma glucose concentration and acid-base values between the groups. No correlation was demonstrated between the age and weight of the patients and the duration of fasting and the plasma glucose concentration. There was a significant elevation of plasma glucose concentration in all four groups after induction of anaesthesia (P less than 0.001) compared with the pre-induction level which is a reflection of the stress of blood sampling and induction of anaesthesia. Infants less than three months of age in the milk-feed group had a significantly higher gastric volume with low pH (P less than 0.05) signifying a potentially greater risk of pulmonary acid aspiration. The practice of timing the last pre-operative feed in infancy according to the infant's normal feeding pattern does not appear to increase the risk factors for pulmonary aspiration, if milk is avoided. A study was carried out to assess the effects of immediate postoperative oral rehydration in 51 unpremedicated women undergoing caesarean section under epidural anesthesia. The patients were randomly assigned to 2 groups: group 1 (n = 22)--fasting at least until 24 hours after the end of the operation, and group 2 (n = 29)--receiving immediate oral intake of fluids (water, tea or coffee with sugar) without limitation of quantity. The 2 groups were compared for the occurrence of postoperative nausea and vomiting, onset of peristalsis, rectal gas emission, first bowel movement, and possible complications. The results demonstrate no significant differences between the parturients who drank immediately postoperatively as compared to those in whom oral fluid intake was delayed for 24 hours or more. It is concluded that immediate postoperative oral rehydration had no harmful effect upon peristalsis post-caesarean section. The effect of preoperative oral fluid intake on the volume and pH of gastric fluid was examined in 45 elective surgical patients ranged in ages from 18 to 70 years. Two hours preoperatively they all received oral roxatidine 75 mg with 10 ml water, immediately followed by 150 ml oral water or 150 ml refreshing drink or no fluid as control. Just after the induction of anesthesia, a Salem-sump tube was put down to the stomach to collect gastric fluid in each patient. The volume and pH of gastric fluid taken were 10.9 +/- 7.9 ml, 16.3 +/- 2.3 in control group, 8.0 +/- 6.0 ml, 6.2 +/- 2.4 in the water group and 6.3 +/- 6.0 ml, 7.1 +/- 1.7 in the refreshing drink group. As there were no significant differences in gastric pH values in the three groups, the highest value was found in the refreshing drink group. No significant difference in VAS of hungry and thirsty feeling was found among the three groups. We conclude that preoperative oral water or refreshing drink with roxatidine 75 mg 2 hours before the start of anesthesia may not increase the risk of aspiration during the induction of anesthesia. The aim of this study was to investigate the relationship between preoperative oral fluids and gastric pH and volume in women undergoing sterilization between one and five days postpartum. Fifty postpartum patients received 150 ml water approximately two to three hours before surgery while 50 postpartum and 50 non-pregnant women were fasted from midnight. After induction of anaesthesia, gastric contents were aspirated using a Salem sump tube and the gastric pH and volume were measured. There were no differences in intragastric pH and volume, median (range), among the postpartum fasted group, 1.19 (0.74-4.57), 22 (1-78) ml, postpartum water group 1.18 (0.70-6.4), 25.5 (3-66) ml and the non-pregnant group 1.27 (0.51-6.63), 25 (3-69) ml. There was no correlation between postpartum interval, 60 (12-120) hr, and intragastric pH or volume. It is concluded that oral water may be given safely two to three hours preoperatively to patients more than one day postpartum. Intragastric volume and acidity were not increased and the findings in postpartum patients were similar to those found in non-pregnant patients. To determine the effects of duration of fasting before elective surgery on gastric fluid pH and volume in children, a prospective, randomized, blinded study of 100 unpremedicated children, aged 1-14 yr, was undertaken. Each child was given 2 mL/kg of water orally and then fasted 2, 4, or 6 h preoperatively. After induction of anesthesia and tracheal intubation, gastric fluid was aspirated through a large-bore, multiorifice orogastric tube. Gastric fluid pH was measured using a calibrated PHM62 radiometer. Gastric fluid volume was the total volume of fluid aspirated from the stomach. The duration of fasting was between 2.0 and 8.5 h. We found that neither gastric fluid pH nor gastric fluid volume correlated with the duration of fasting. The mean (+/- SD) gastric fluid pH was 1.80 +/- 0.79 and the mean (+/- SD) gastric fluid volume was 0.56 +/- 0.39 mL/kg. Gastric fluid pH was less than 2.5 and volume greater than 0.4 mL/kg in 53% of children. We conclude that healthy children may receive 2 mL/kg of water up to 2 h before elective surgery without decreasing gastric fluid pH or increasing gastric fluid volume beyond values obtained after fasting for 6 h. The effect of a 3-hour versus a 10-hour preoperative fasting interval on the gastric residual volume and gastric pH of pediatric patients was evaluated. Forty-four healthy infants, 1 month to 5 years of age, were randomly assigned to one of two groups. The 3-hour nil per os (NPO) group consisted of 19 infants kept NPO for 3 hours following ingestion of up to 4 ounces of 5% dextrose in water (D5W). The control group consisted of 25 infants who remained NPO an average of 10 hours prior to surgery. Gastric residual volume was calculated using the dye-dilution technique. After the dye marker was injected into the stomach, complete aspiration of the stomach (including the volume of dye marker plus residual gastric contents) was attempted as another method to measure gastric residual volume. There were no significant differences in gastric residual volume between the 3-hour and the 10-hour NPO groups using either the dye-dilution or aspiration methods. However, there were significant differences between the two measuring techniques. Gastric residual volume was significantly greater in volume when measured by the dye-dilution technique than it was when measured by the aspiration technique in both the 10-hour (p less than 0.009) and the 3-hour (p less than 0.0009) NPO groups. Complete aspiration of a known volume of fluid injected through the orogastric tube was not possible in 23 of the 44 (52.4%) infants. Mean gastric pH was less than 2.0 in both groups.(ABSTRACT TRUNCATED AT 250 WORDS) The effect of oral fluids before operation, followed by intramuscular morphine, on gastric volume and pH was examined in 150 elective surgical patients, ASA physical status 1 and 2, who were randomly assigned to one of the three groups of 50 each. Group 1 (control) continued their overnight fast; patients in Groups 2 and 3 received 150 ml water 2 hours before the scheduled time of surgery. Patients in Group 3 received intramuscular morphine 0.15 mg/kg and promethazine 0.5 mg/kg one hour before operation. The residual gastric volume was obtained by suction and its volume and pH measured immediately after induction of anaesthesia. Statistically significant (p less than 0.05) decrease in residual gastric volume was observed in Groups 2 and 3 as compared to Group 1. However, the difference between these two groups was not statistically significant. There was no statistically significant difference in pH among the three groups. Overnight fluid fasting is not justified in elective surgical patients. Morphine can be safely given one hour before surgery in patients who have received water (150 ml) 2 hours before operation. One hundred day surgical patients undergoing first trimester termination of pregnancy were randomly allocated to receive either 150 ml of clear fluid 1.5-2 hours before anaesthesia or to remain fasted from midnight the night before. Patients were anaesthetised using a total intravenous technique which consisted of propofol and alfentanil. No adverse intra-operative events were noted in either group. There were no significant differences in immediate recovery time, or pain, nausea and headache scores at 30 or 120 minutes following recovery. The fasted group had less pain (p less than 0.05) at 60 minutes after recovery than the fluid group, although the mean pain scores in both groups were low. Eighty two per cent of the patients returned questionnaires about pain, nausea and headache scores on arriving home, and at 12 and 24 hours after surgery. There were no significant differences between the two groups. In conclusion, pain, nausea and headache scores are low following total intravenous anaesthesia with propofol and alfentanil for termination of pregnancy and these were unaffected by the administration of 150 ml of clear fluid given approximately 1.5 hours pre-operatively. The effect of pre-operative intake of oral water and ranitidine on gastric fluid volume and pH was studied in 75 children of American Society of Anesthetists (ASA) grade I and grade II undergoing elective surgery. Group I patients fasted from midnight and acted as control. Group II patients received 5 ml/kg plain water orally 3 hours before surgery. Group III children received 5 ml/kg of plain water and 2 mg/kg of ranitidine orally 3 hours before surgery. Mean volume of gastric aspirate was comparable in all 3 groups (p > 0.05). Mean pH was significantly higher in ranitidine treated patients (5.12 +/- 1.73) as compared to non-ranitidine treated patients (2.26 +/- 0.57 and 2.53 +/ 0.79 in group I and group II respectively). Number of patients at risk (pH < or = 2.5 and volume > or = 0.4 ml/kg) was not significantly different in group I and group II. Mean thirst and behaviour scores were significantly higher in fluid treated patients (groups II and III) as compared to control (p < 0.01). To conclude, administration of pre-operative water (5 ml/kg) along with ranitidine (2 mg/kg) favourably modifies gastric fluid volume and pH, improves patient behaviour and minimises the number of patients at risk of aspiration pneumonitis, should the child aspirate.
There is no evidence that children who are denied oral fluids for more than six hours preoperatively benefit in terms of intraoperative gastric volume and pH compared with children permitted unlimited fluids up to two hours preoperatively. Children permitted fluids have a more comfortable preoperative experience in terms of thirst and hunger. This evidence applies only to children who are considered to be at normal risk of aspiration/regurgitation during anaesthesia.