This retrospective study demonstrates the clinical effectiveness of an anesthesiologist-administered intravenous sedation outside of the main operating room for pediatric upper gastrointestinal endoscopy in a developing country. The complication rate of our study is relatively high. However, the serious complications were none. IVS for pediatric UGIE procedure in children 12 years of age and younger is challenge and requires an experienced anesthesiologist as well as appropriate monitoring. Anesthetic personnel should remind themselves to use more sensitive equipments to detect potential complication such as end tidal CO2 and carefully select more appropriate patients.
UGIE procedure in children is an important and effective tool for the diagnosis and treatment of upper digestive tract diseases. The indications for upper endoscopy in the pediatric age group are similar to those for adult endoscopy [8
]. These procedures are generally performed either with IVS in the endoscopy room, or under GA in the operating room [9
]. The decision to use GA is usually based on the patients' parameters such as age, diagnosis, respiratory compromise and severity of disease. In some centers, GA is used on all infants, children and adolescents [3
]. However, in other centers, IVS is used for the procedures. With IVS, several medication combinations have been used successfully [9
In a developing country where pediatric UGIE performed at increasing rates, the majority of cases are performed under general anesthesia in the operating room (OR). At Siriraj Hospital, there is a dedicated endoscopy unit with dedicated anesthesia service. Over the last two years, 2006 to 2008, we performed most pediatric UGIE with IVS [5
]. We followed the guidelines provided by the American Academy of Pediatrics and American Academy of Pediatric Dentistry and ASA standards for sedation providers [4
]. Our previous reviews of IVS practice in pediatric population showed that it can be done safely with various sedative combinations with proper monitoring and anesthesiology service supervision.
Majority of children received propofol in combination with other sedatives. Propofol has gained wide acceptance among adult gastroenterologist. Its use in pediatric population has been shown to be safe, effective and reliable [10
]. In Thailand, sedation with propofol is administered by anesthesiologist. The drug combination provides synergistic action while lowering the doses of each agent. Our practice reflects this where many different combination regimens were used [5
]. Propofol is the most common agent used in combination with midazolam and fentanyl in this study. Additionally, we did not observe hemodynamic instability, emergence reactions, hallucinations, increased salivation or laryngospasm with the use of ketamine combining regimen. This observation was similar in the previous studies [17
Cardiopulmonary complications account for more than half of the major complications during endoscopy, and are often related to hypoxia, especially in children less than 1 year old [20
]. In our study, the overall adverse event was relatively high (25.4%). Cardiovascular complications accounted for the majority (16.2%) followed by respiratory complications (9.2%). However, all complications were transient and easily treated with no adverse sequelae. Many previous studies involving the use of propofol and other combination sedative drugs have reported slightly higher adverse events [22
]. In our study, there was significant difference in the mean dose of propofol between the three aged groups.
In a study by Barbi and colleagues, major desaturation was noted in 0.7% of all the children, and transient desaturation that resolved sponstaneously occurred in 12% of all the procedures [22
]. Additionally, the study by Yildizdaş et al. demonstrated that the use of propofol and midazolam/fentanyl in 126 children had 16.6% incidence of respiratory depression as shown by high end-tidal carbon dioxide (>50 mmHg) [23
]. The high incidence of respiratory depression reflected the better detection of respiratory depression by the use of end-tidal carbon dioxide. In our study, complication rate is comparable to studies that did not use end-tidal carbon dioxide monitoring [22
]. ASA physical status III-IV has been shown to be a predictor of increased risk for sedation-related complications [24
]. There is also a concern for increased respiratory complication in patients undergoing UGIE procedures. Endoscope can potentially compress and obstruct airway.
Several publications described the use of propofol for sedation by physicians or providers other than anesthesiologists [24
]. Consequently, there was a difference in outcomes once nonanesthesiologists use propofol. When a dedicated pediatric sedation team involving an anesthesiologist was utilized, the reported successful sedation rates were 100%, and adverse events ranged from 1.7 to 5% [28
]. There was no failure of sedation in this study. However, two patients became more deeply than intended and required unplanned endotracheal intubation. Finally, all procedures were completed as intended. A high success rate in our study is due to the procedure is performed by an experienced endoscopist and is sedated by an experienced anesthesiologist. Consequently, our center had a dedicated anesthesia service involved with sedation and the use of basic noninvasive monitoring, which includes noninvasive blood pressure monitoring, pulse oximetry, and electrocardiogram. Additionally, the safe and successful sedation is also dependent on proper preparation, evaluation, monitoring, and appropriate skills to rescue the patient, and proper recovery [27
Our study has several limitations. This is a retrospective paper of a cohort of patients undergoing pediatric UGIE with IVS. We accept that there are limitations with chart review in regards to proper and complete documentation. We also realized that with this review, the study is reflected in the variety of regimen and sedative drugs used for IVS. In addition our cohort varied widely in age range. Therefore, the drug requirement, drug doses, and side effects varied as well. According to the design of study, we defined an alteration of blood pressure by 20% from baseline, and a decrease in heart rate by 30% from baseline as the complication. The complication rate in this paper was also relatively high. Moreover, we did not use the end tidal CO2 monitoring. Overall, even with these limitations, we believe that the study findings are applicable to the sedation practice and to remind the physicians for sedation the pediatric patients for UGIE procedures.
In summary, this study shows the clinical effectiveness of an anesthesiologist-administered intravenous sedation outside of the main operating room for pediatric upper gastrointestinal endoscopy in a developing country. Although, the complication rate of our study is relatively high. All complications were transient and easily treated with no adverse sequelae. We also recommend the use of more sensitive equipments to detect potential complication such as end tidal CO2 and carefully select more appropriate patients for pediatric UGIE.