Jones JE, Tabaee A, Glasgold R, Gomillion MC. Efficacy of Gastric Aspiration in Reducing Posttonsillectomy Vomiting. Arch Otolaryngol Head Neck Surg. 2001;127(8):980-984. doi:10.1001/archotol.127.8.980
Copyright 2001 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2001
To determine the effectiveness of postoperative gastric decompression in reducing the incidence and complications associated with vomiting following tonsillectomy.
A prospective, randomized controlled study.
Private office and clinic of a university teaching hospital and research center.
Eighty pediatric patients ranging in age from 22 months to 11 years, American Society of Anesthesiologists class I or II, undergoing tonsillectomy with or without adenoidectomy were enrolled in the study. Six were excluded from the final analysis, 5 because of failure of the parents to complete and return the data forms and 1 because of postoperative bleeding. Of the 74 patients included in the study, 35 were in the control group and 39 were in the study group.
The 39 patients in the study group underwent postoperative aspiration of gastric contents with an orogastric tube placed under direct visualization while the patient was still under general anesthesia. The 35 patients in the control group did not undergo gastric aspiration following surgery.
Main Outcome Measures
The incidence of vomiting, the number of episodes of vomiting before and after hospital discharge, the total volume of emesis, the postoperative length of stay, the need for rescue antiemetic prophylaxis, and the number of readmissions to the hospital for persistent vomiting were noted.
No statistically significant difference (P<.05) was noted between the control group and the study group for the percentage of patients experiencing vomiting (74% vs 85%), the mean number of episodes of vomiting before (2.6 vs 2.8) and after (0.8 vs 0.7) hospital discharge, the mean volume of emesis (157 mL vs 222 mL), the postoperative length of stay (394 minutes vs 334 minutes), the percentage of patients requiring rescue antiemetics (34% [12 patients] vs 33% [13 patients]), and the percentage of unplanned admissions because of vomiting (9% [3 patients] vs 15% [6 patients]).
Our results indicate that gastric aspiration does not decrease the incidence of vomiting following tonsillectomy.
POSTOPERATIVE vomiting represents the most common complication of pediatric tonsillectomy and adenoidectomy. Despite advances in anesthetic and surgical technique, incidences as high as 75% have been reported.1- 3 Persistent vomiting is costly both in terms of financial effect and potential medical sequela.4,5 The cause of postoperative vomiting in the pediatric population is thought to be multifactorial with patient characteristics, anesthetic medications, surgical manipulation, and postoperative care all hypothesized to contribute.2,4- 9
In response to this "Big ‘Little' Problem,"3 multiple studies have investigated the effects of newer anesthetic agents and antiemetic prophylaxis on postoperative vomiting.10- 18 In general, the results of these studies have been mixed. Marginal improvements, unfavorable adverse effect profiles, and high costs have limited the universal adoption of any single protocol. The use of gastric aspiration in reducing postoperative vomiting has been advocated in the older medical literature and several review articles.6,19,20 However, recent studies have failed to demonstrate any benefit of gastric aspiration in reducing postoperative vomiting in gynecologic or general surgical patients.21,22 Further, a recent literature search failed to find any prospective studies examining the effectiveness of gastric aspiration in reducing postoperative vomiting following tonsillectomy, adenoidectomy, or adenotonsillectomy. This study determined the efficacy of gastric aspiration in reducing the incidence and complications associated with posttonsillectomy vomiting in a pediatric population.
The study was approved by the Institutional Review Board Committee on Human Rights in Research, Weill College of Medicine at Cornell University, New York, NY. Informed consent was obtained from the parents of 80 pediatric patients, American Society of Anesthesiologists class I or II, who underwent tonsillectomy with or without adenoidectomy at New York Hospital between July 9, 1997, and November 8, 1999. Patients were alternately randomized to the control group (n = 35) or the study group (n = 39) at the time of enrollment. Patients in the study group underwent gastric aspiration with an orogastric tube prior to extubation following surgery. Those in the control group did not undergo gastric aspiration. Patients with any remarkable history of gastrointestinal disorders were ineligible for the study.
The anesthetic protocol was standardized throughout the study and all procedures were supervised by the same anesthesiologist (M.C.G.). Inhalational anesthesia was achieved with 2% sevoflurane delivered in a combination of 30% oxygen and 70% nitrous oxide. Intravenous morphine sulfate (0. l mg/kg) was administered at the time of induction. Intravenous mivacurium chloride (0.25 mg/kg) was used for muscle paralysis to facilitate intubation. Intraoperative steroids and antibiotic agents were not used. Patients were not given prophylactic antiemetics or steroids.
The surgical technique was standardized and all procedures were supervised by the same pediatric otolaryngologist (J.E.J.). Tonsillectomy was performed using electrocautery; hemostasis was obtained by packing the tonsillar fossa followed by suction electrocautery. Adenoidectomy was performed using adenoid curettes and St Clair–Thompson forceps. Hemostasis was obtained with nasopharyngeal packing followed by suction electrocautery.
In the study group (n = 39 patients), an orogastric tube was placed postoperatively under direct visualization and the gastric contents were aspirated prior to emergence from anesthesia. A mouth gag was in place at the time of suctioning. The 35 patients in the control group emerged from anesthesia without undergoing placement of an orogastric tube. The attending anesthesiologist (M.C.G.) who followed up the patients postoperatively for emesis was not in the operating room at the time of orogastric aspiration and was thus masked. All 74 patients were transferred to the postanesthesia care unit following extubation. Postoperative pain was addressed with a combined therapy of acetaminophen (10 mg/kg) and codeine phosphate (0.5 mg/kg) given orally every 4 hours as needed. Intravenous fluids were continued until oral liquids were tolerated. Rescue prophylatic antiemetics were provided only in cases of persistent vomiting. After the third episode of vomiting, the anesthesiologist (M.C.G.) administered a single dose of intravenous metoclopramide hydrochloride (0.25 mg/kg).
The patients were observed in the ambulatory step down unit until the following criteria for discharge were met: stable vital signs and airway, stable wound, tolerant of oral fluids, alert, and ambulating. There was no predetermined minimum postoperative length of stay. Emesis was defined as the forceful expulsion of gastric contents from the mouth. The incidence and volume of each episode of emesis was recorded in a log by the postanesthesia care unit nurses and the parents for a 24-hour period following the patient's arrival in the postanesthesia care unit. The anesthesiologist, nurses, and parents were masked to the randomization of each patient. The parents were instructed to send the completed record of postoperative vomiting to the senior author (J.E.J.).
Data on the number of episodes of vomiting, total volume of emesis, postoperative length of stay, administration of rescue prophylactic antiemetics, and readmission to the hospital for persistent vomiting were collected from the hospital medical record, parents' logs, and follow-up telephone calls made by the research team. Mean (SD) or percentage was used to describe each variable. The Wilcoxon rank sum test was used to compare the 2 study groups and the Fisher exact test was used to examine categorical variables. P<.05 was considered statistically significant.
Eighty patients were initially enrolled in the study. Five patients were excluded from the final analysis for failing to return the data forms; 1 was excluded for postoperative bleeding following extubation. Of the 74 patients included in the study, 35 were in the control group and 39 were in the study group. The age of the patients ranged from 22 months to 11 years. No statistically significant difference was noted between the 2 groups for age, sex, weight, intraoperative blood loss, history of motion sickness, or diagnosis (Table 1). Although demographic factors were not strictly controlled, the 2 groups were considered statistically similar enough for direct comparison. One patient in each group underwent tonsillectomy; all of the other patients underwent adenotonsillectomy.
There was no statistically significant difference between the control group and the study group in the overall incidence of vomiting (74% [26 patients] vs 85% [33 patients]), mean number of episodes of vomiting before hospital discharge (2.6 vs 2.8), or mean number of episodes of vomiting after hospital discharge (0.8 vs 0.7). Further, the mean volume of emesis for the patients who experienced postoperative vomiting was similar for the control group and study group (157 mL vs 222 mL). Prophylactic antiemetic rescues were required in 34% (12/35) of the control group patients and 33% (13/39) of the study group patients (Table 2).
The postoperative length of stay was defined as the time from extubation to hospital discharge. There was no predetermined minimum postoperative length of stay. In the control group, the mean postoperative length of stay for the 29 patients discharged on the day of the surgery was 394 minutes. This was similar to the mean length of stay of 334 minutes for the 32 patients in the study group (Table 2). In the control group, 6 of the 35 patients were admitted overnight following surgery. Three of these were because of persistent vomiting, 2 were planned based on the patient being younger than 3 years, and 1 was planned based on a history of mild factor VII deficiency. In the study group, 7 of the 39 patients were admitted overnight following surgery. Six of these were because of persistent vomiting and 1 was planned based on the patient being younger than 3 years. No statistically significant difference was noted between the control group and the study group for postoperative length of stay or unplanned admissions. In the study group, there were no complications attributable to the placement of the orogastric tube or gastric aspiration.
Tonsillectomy and adenoidectomy are among the most frequently performed pediatric surgical procedures. Postoperative vomiting represents one of the most common complications and the single most common reason for unplanned hospital admission following adenotonsillectomy.2,4,9 In a study of 1476 pediatric patients undergoing general anesthesia, Kermode et al9 found a 24% overall incidence of postoperative vomiting and a 54% incidence of vomiting following tonsillectomy. Incidence of posttonsillectomy vomiting as high as 75% has been reported in the literature.3,9 In addition to the potentially fatal complications of dehydration, electrolyte imbalance, and aspiration pneumonitis, vomiting has been reported to result in a level of physical and psychological distress exceeding that of the operation in 54% to 71% of patients surveyed in an ambulatory setting.4,5 The economic consequences of postoperative vomiting are likewise significant with both direct costs such as medical staffing and medications as well as indirect costs such as fewer surgical cases and slower patient recovery contributing to this major financial sink.
The cause of posttonsillectomy vomiting is theorized to be multifactorial. Patient characteristics associated with increased incidence include young age (peak incidence during ages 6-16 years), female sex, history of postoperative vomiting or motion sickness, history of gastroparesis, and obesity. Research investigating the link between anesthetics and postoperative vomiting indicates that inhalational anesthetics, nitrous oxide, and opioids all tend to be proemetogenic while newer agents such as propofol tend to be less so. Postoperative factors linked to emesis include pain, dizziness, ambulation, and oral intake. The mechanism of these factors in triggering emesis varies and includes activation of chemoreceptors and mechanoreceptors in the oropharynx and stomach by swallowed blood and intraoperative manipulation, direct stimulation of the chemoreceptor trigger zone in the area postrema, stimulation of the trigeminal nerve, and vestibular input to the vomiting center.5,7- 9,17
Given the increasing insight into the pathophysiology of proemetic factors, multiple studies have focused on methods to decrease posttonsillectomy vomiting. The use of prophylactic antiemetics has been shown to be effective in reducing posttonsillectomy emesis. Ondansetron hydrochloride, specifically, has received a great deal of attention with some studies demonstrating a 40% to 50% reduction in the incidence of posttonsillectomy vomiting.10- 14 Although the use of antiemetics has been advocated by some authors, their universal adoption has been precluded by insufficient prophylaxis, untoward adverse effects, and high cost. Recent research in anesthesia has concluded that the use of propofol in place of inhalational anesthetics results in a 34% decrease in posttonsillectomy vomiting.17 The anesthetic protocol used in our study was supplied in a standardized fashion to minimize confounding variables. Steroids were also not given since studies investigating their use in patients who undergo tonsillectomy have been conflicting.15,16
In a review article addressing anesthetic issues in outpatient otolaryngology surgery, Pasternak6 states that gastric aspiration with an orogastric tube prior to extubation is essential to decreasing nausea, emesis, and pulmonary aspiration. Further, this practice has been advocated in multiple review articles dating back several decades.19,20 However, in a recent review of the literature, we were unable to find any prospective studies addressing the efficacy of gastric aspiration in reducing posttonsillectomy vomiting. Regardless of its unproven efficacy and potential complications, it remains a practice commonly performed by otolaryngologists and anesthesiologists.
Postoperative gastric decompression with an orogastric tube is generally considered to be a safe procedure. Most complications secondary to orogastric and nasogastric tubes are associated with long-term placement.23 When used to aspirate gastric contents postoperatively, orogastric tubes have been associated with inadvertent placement into the trachea, esophageal perforation, uvular trauma with secondary edema, and gastric ulceration. Although these complications are rare, they have the potential to result in significant morbidity.23- 30 In our series, we did not detect any complications attributable to the use of orogastric tubes.
The efficacy of gastric aspiration in reducing postsurgical vomiting has been addressed in 2 recent prospective studies. In a study of 201 patients who underwent hysterectomy, Hovorka et al22 showed no statistically significant difference in the incidence of vomiting between patients who underwent postoperative gastric aspiration and patients who did not (79% vs 70%, respectively). Trepanier and Isabel21 actually demonstrated a higher incidence of vomiting in patients who underwent postoperative gastric aspiration with an orogastric tube (17% vs 6.8%) in a study of 256 ambulatory general surgical patients. These studies seem to indicate that reducing gastric distention with an orogastric tube does not reduce postoperative vomiting.These studies cannot be directly correlated with pediatric otolaryngology because patients who undergo tonsillectomy experience additional proemetic stimuli including intragastric blood, manipulation of the posterior pharynx, and stimulation of the trigeminal nerve. Therefore, addressing gastric aspiration in patients who undergo tonsillectomy remains a critical next step.
Indirect evidence concerning the efficacy of gastric aspiration in reducing posttonsillectomy vomiting is available from recent studies. In their investigation of the role of prophylatic antiemetics in reducing posttonsillectomy vomiting, Ferrari and Donlon10 and Furst and Rodarte11 required all patients, including the control groups, to undergo gastric aspiration. The incidence of vomiting in these control groups was high (62% and 70%, respectively). In comparison, 3 similar studies evaluating prophylactic antiemetics were designed so that no patients underwent gastric aspiration. The control groups of these studies also had high incidences of posttonsillectomy vomiting (54%-73%).12- 14 Although experimental and surgical variables preclude the direct statistical comparison of these studies, they seem to indicate that gastric aspiration may not significantly affect the incidence of posttonsillectomy vomiting.
The goal of this study was to determine the efficacy of gastric aspiration in reducing posttonsillectomy vomiting in a pediatric population. Our data showed no statistically significant reduction in the incidence of vomiting, the number of episodes of vomiting, or total volume of emesis. Further, there was no difference in the need for rescue prophylatic antiemetics or the number of readmissions for persistent vomiting. This is consistent with the results of the studies noted earlier. The incidence of vomiting in our study groups and control groups (85% and 74%, respectively) are high compared with previous studies. However, other studies defined postoperative vomiting as 3 or more episodes, whereas our protocol included all cases of vomiting. The limited sample size of our study may also be a factor in the high incidence.
With the increasing emphasis placed on financial efficiency in health care, the issue of postoperative length of stay in ambulatory surgery has taken on greater significance. Postoperative emesis represents a major factor in delaying the time of hospital discharge for patients who undergo tonsillectomies, as described earlier. One of the major goals of decreasing the incidence of postoperative vomiting is to decrease the postoperative length of stay and, therefore, improve efficiency. In our study, there was no minimum observation period following surgery and patients were discharged after meeting discharge criteria. In addition to having no detectable effect on the incidence of vomiting, gastric aspiration also failed to result in any significant reduction in the postoperative length of stay.
Our data do not support the routine use of orogastric tube placement for gastric aspiration following pediatric tonsillectomy. There was no reduction in the incidence of postoperative vomiting, number of episodes of vomiting, postoperative length of stay, or unplanned hospital admissions. Our results are consistent with the results of previous studies in other surgical fields. Therefore, the routine use of gastric aspiration requires reassessment. Further studies are needed to evaluate the role of gastric aspiration in select cases in which significant bleeding or gastric distention is a concern.
Accepted for publication March 27, 2001.
Corresponding author: Jacqueline E. Jones, MD, Department of Otorhinolaryngology, Weill College of Medicine at Cornell University, Starr Bldg, Suite 541, 520 E 70th St, New York, NY 10021 (e-mail: firstname.lastname@example.org).