© Springer International Publishing Switzerland 2017
Basavana G. Goudra and Preet Mohinder Singh (eds.)Out of Operating Room Anesthesia10.1007/978-3-319-39150-2_77. Anesthesia for Upper GI Endoscopy Including Advanced Endoscopic Procedures
(1)
Department of Anesthesiology and Perioperative Medicine, Penn State Milton S. Hershey Medical Center, 500 University Drive – HU33, 850, Hershey, PA, USA
Abstract
One of the most frequent locations for providing out of operating room anesthesia is the endoscopy suite. In 2009 an estimated 6.9 million upper endoscopy procedures were performed according to the American Society for Gastrointestinal Endoscopy (ASGE). Utilization of anesthesia services for these procedures has risen to 30–35 % of patients nationwide (Goulson and Fragneto, Anesthesiology Clin 27:71–85, 2009). Sedation offered by anesthesia providers has been shown to play a crucial role in safety, efficiency, patient satisfaction and throughput.
Anesthesia providers are increasingly consulted to provide sedation for newer, more complex endoscopic procedures. The basic principles and guidelines for evaluating and preparing a patient for a screening upper endoscopy are applicable to the anesthetic management of these advanced endoscopic procedures. In addition, the anesthesia provider must be knowledgeable of the indication, technique, complexity and length of these new procedures. Understanding the risks, complications and patient comorbidities is crucial to providing safe sedation.
Upper endoscopic procedures are done for either diagnostic, prognostic, and/or therapeutic purposes. The interventions discussed in this chapter include: standard endoscopy (EGD), endoscopic ultrasound (EUS), endoscopic cystenterostomy, pancreatic necrosectomy and Per oral endoscopic myotomy (POEM).
Keywords
EGDEndoscopic Ultrasound (EUS)Pancreatic NecrosectomyCystgastrostomyEndoscopic cystenterostomyPer Oral Endoscopic Myotomy (POEM)AchalasiaTopicalizationBenzocaineCapnothoraxCapnomediastinumAir EmbolismPerforationIntroduction
One of the most frequent locations for providing out of operating room anesthesia is the endoscopy suite. In 2009 an estimated 6.9 million upper endoscopy procedures were performed according to the American Society for Gastrointestinal Endoscopy (ASGE). Utilization of anesthesia services for these procedures has risen to 30–35 % of patients nationwide [1]. Sedation offered by anesthesia providers has been shown to play a crucial role in safety, efficiency, patient satisfaction and throughput.
Anesthesia providers are increasingly consulted to provide sedation for newer, more complex endoscopic procedures. The basic principles and guidelines for evaluating and preparing a patient for a screening upper endoscopy are applicable to the anesthetic management of these advanced endoscopic procedures. In addition, the anesthesia provider must be knowledgeable of the indication, technique, complexity and length of these new procedures. Understanding the risks, complications and patient comorbidities is crucial to providing safe sedation.
Upper endoscopic procedures are done for either diagnostic, prognostic, and/or therapeutic purposes. The interventions discussed in this chapter include: standard endoscopy (EGD), endoscopic ultrasound (EUS), endoscopic cystenterostomy, pancreatic necrosectomy and Per oral endoscopic myotomy (POEM).
EGD
A flexible forward viewing endoscope is passed through a mouth piece, over the tongue with visual access to the esophagus, stomach, and duodenum.
Through a working channel, instruments can be passed through the scope to perform biopsies, treat bleeding, or deploy instruments including luminal stents.
Common indications for EGDs include:
Evaluation of reflux disease and its sequelae
Evaluate and possibly treat causes of dysphagia, odynophagia, including acute food impaction
Dyspepsia and peptic ulcer disease
Iron deficiency anemia
Assess for celiac disease or other proximal small bowel mucosal pathology
Screen for and/or treat esophageal varices
Diagnosis and possibly palliate luminal foregut tumors
EUS (Endoscopic Ultrasound)
As in EGD, a flexible forward viewing endoscope is passed through a mouth piece, over the tongue allowing visual access to the esophagus, stomach, and duodenum.
EUS technologyuses an oblique angled luminal camera making visualization of the lumen difficult
Two different echoendoscopes:
Radial: gives a 360° ultrasound images perpendicular to the scope tip, used for esophageal cancer, subepithelial masses, etc. Biopsy cannot be taken through it.
Linear: gives a focused ~170° image along the access of the probe used to guide fine needle aspiration under direct visualization.
Used primarily to locally stage foregut tumors as well as diagnose non-luminal foregut tumors (pancreas, liver, abdominal and mediastinal lymph nodes) and pancreatic cysts using fine needle aspiration [2] Has the highest sensitivity for choledocholithiasis and small pancreatic masses of any imaging modality
Endoscopic Cystenterostomy (Cystgastrosomy)
Usually performed using a linear EUS followed by needle aspiration of the cyst cavity. After this a wire is coiled in the cyst under fluoroscopy, and then the tract is sequentially dilated up 10–20 mm in size. Following this, trans-luminal stent(s) are placed to allow ongoing drainage and formalize an enterocystic fistula [2].
Creation of a trans-luminal ostomy between the lumen and a cyst, usually either symptomatic walled off pancreatic necrosis or pseudocyst, to facilitate drainage and possible access for debridement (necrosectomy).
Endoscopic Necrosectomy
After creation or revision of a cystenterostomy, an endoscope is driven through the enteric lumen into the cyst cavity to perform direct necrosectomy of necrotic solid material
Material is gently pulled free from the cavity walls and deposited usually in the stomach or duodenum, but if a large piece exists, it can be removed per os [3]
Frequently these are long (>90–120 min) procedures.
POEM (Per Oral Endoscopic Myotomy)
Utilizes a standard upper endoscope and advanced per oral cavity as in normal EGD.
Treatment of choice now for achalasia
An incision is made through the mucosa into the submucosa of the esophagus ~10–15 cm proximal to the gastroesophageal junction, and using endoscopic dissection, a tunnel is made distally extending 2–3 cm into the stomach [4]
The esophageal muscles, preferentially the circular muscles, are incised. The incision is about 2 cm into the stomach and 7 cm proximal into the esophagus [4].
At the end, the incision site into the tunnel is closed with multiple clips or sutures.
Focused History and Physical Findings for Patients Presenting for Upper GI Endoscopy
The same principles used for pre-anesthetic evaluation of surgical cases should be applied to pre-evaluation of GI endoscopy procedures. Includes review of medical, anesthetic and medication history and completion of a focused physical examination with review of any pertinent diagnostic studies [5].
Requires a well-defined process in order to prevent the presentation of patients with inadequate work up on the day of the procedure.
Majority of endoscopy centers perform a phone history and triage patients prior to procedure date. Any concerning findings are flagged and reviewed by a physician to determine if further workup is indicated.
It is critical to determine during the preanesthetic evaluation the most appropriate location for performing the procedure (Endoscopy suite versus Operating Room). The anesthesia provider must take into account patient comorbidities and complication risk of procedure to ensure the availability of specialized monitoring, airway equipment and additional personnel in case more serious anesthesia complications arise.
Pertinent Approach to Taking the History
Obtain prior anesthetic history to determine if patient had known complications, difficult airway or family history of malignant hyperthermia.
Many of the indications for performing an upper GI endoscopy include signs and symptoms that are associated with increased risk of aspiration.
Past medical history predisposing to increased aspiration risk includes: severe gastroesophageal reflux disease, delayed gastric emptying (diabetes, chronic opioid use, pregnancy), dysphagia, achalasia, increased intraabdominal pressure (ascites, obesity) [6].
Determination of aspiration risk will dictate need for protection of airway with endotracheal intubation.
Past medical history that is indicative of increased risk of airway obstruction include: history of snoring, obstructive sleep apnea (OSA), excessive daytime sleepiness.
Past medical history indicative of increased incidence of hypoxia during sedation include: history of OSA, obesity, tobacco use, shortness of breath, asthma, COPD, home oxygen use, reactive airway disease or recent upper respiratory infection [7].
Patients with the aforementioned medical history may exhibit increased volume of secretions which could predispose to coughing, bronchospasm and laryngospasm during procedure.
Past medical history suggesting an increased risk of bleeding: liver disease, esophageal varices, prior GI bleeding, anticoagulation, known coagulopathies (e.g. Hemophilia)
Pertinent Approach to Performing the Physical Examination
A focused physical exam on day of the procedure should evaluate for factors increasing the risk of obstruction/hypoxia, aspiration and cardiopulmonary depression. The skilled anesthesiologist will document all of the following prior to the procedure.
Vital signs
Body Mass Index
Airway exam: Modified Mallampati score, neck circumference, thyromental distance, presence of craniofacial anomalies, neck range of motion
Pulmonary auscultation with documentation baseline breath sounds and added sounds (if any).
Visual inspection and palpation of abdomen for ascites in patients with history of liver disease. Paracentesis may be required pre procedure if there is respiratory compromise due to compression of the diaphram.
Cardiac auscultation with documentation of new murmurs or other abnormal findings.
Dental examination for any loose teeth that may become dislodged due to bite block, endoscope or instrumentation of the airway.
Obtain current hemoglobin levels in patients with history of GI bleed and anemia
Patient Optimization
As with any preoperative evaluation, the goal is to determine whether the patient’s medical problems are optimized prior to delivery of an anesthetic.
These same principles apply to anesthesia out of the operating room for endoscopic procedures.
The severity of the patient’s comorbidities is weighed against the procedure risk.
EGD is considered a minimally invasive low risk procedure.
EUS, Pancreatic Cyst Gastrostomy, Necrosectomy, and POEM are considered higher risk procedures.
Emergent or urgent procedures may not allow time for complete patient optimization and as a result are considered to be higher risk.
Cardiac optimization should follow 2014 ACC/AHA guidelines on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery.
Patients with Cardiac Implantable Electronic Device (Pacemaker and AICD) should be optimized per consensus guidelines published in July 2011 as a joint project involving the Heart Rhythm Society, American Society of Anesthesiologists, American Heart Association and the Society of Thoracic Surgeons.
Respiratory symptoms should be at baseline without recent increase in oxygen requirements, dyspnea, and hospitalizations or emergency room visits for pulmonary disease exacerbations.
Anticoagulant management and recommendations should be determined by the most recent guidelines from the ASGE. These are formulated by determination of the risk of bleeding versus the risk of thromboembolic event.
Confirmation and documentation of NPO status. NPO guidelines for general anesthesia per American Society of Anesthesiology.
Patients presenting with achalasia for POEM procedure should be given strict guidelines for clear liquid diet 2 days prior to procedure to reduce aspiration risk [4].
Commonly Used Anesthetic Techniques and Sedative Medications for Standard and Advanced Upper Endoscopy
Selection of Appropriate Sedation Level
Sedation requirements for upper endoscopic interventions are dependent on patient demographics and the exact procedure to be performed. Sedation may range from light/moderate sedation to general anesthesia [8]. General anesthesia may be provided with or without endotracheal intubation.
Determination of appropriate sedation technique must take into account medical history, sedation history, patient preference, and level of discomfort anticipated by procedure.
EGDs are short in duration and less invasive; typically, general anesthesia is not required.
Conversely, EUS is more complex and stimulating. The EUS scope is larger in caliber, needle aspiration is performed to obtain biopsies and duration of procedure is longer. All of these factors necessitate deep sedation/general anesthesia for patient comfort and optimal operating conditions for the endoscopist.Related posts:
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