TSRA Content:
Author: Irsa Hasan, MD
This is a revision and update from the previous edition of the TSRA Primer in Cardiothoracic Surgery written by Roman Petrov, MD, and Carlos Anciano, MD
Contrast Esophagography
Introduction:
Multiple imaging modalities can be used to investigate diseases of the esophagus and foregut, including plain x-rays, computed tomography, positron Emission tomography, and magnetic resonance imaging. However, contrast esophagoscophy is frequently the initial imaging modality of choice for evaluating suspected esophageal disease.
In addition to being non-invasive, inexpensive, and readily available, these dynamic studies provide valuable information about swallowing function, esophageal motility, gastroesophageal reflux, and structural abnormalities of the esophagus and foregut. It is essential for thoracic surgeons to have knowledge of how the studies are performed, as well as how to interpret them.
Indications:
Contrast esophagography is a useful tool in the work-up of symptoms such as dysphagia, odynophagia, atypical and typical symptoms of gastroesophageal reflux (GER), and chest pain (after ruling out a cardiogenic etiology). It can aid in the diagnosis and evaluation of esophageal obstruction, benign and malignant lesions, strictures, suspected motility disorders, esophagitis, varices, and suspected perforation. Contrast esophagography also plays a vital role in postoperative assessment following esophageal and foregut surgery.
Contrast Mediums and Single vs. Double Contrast: Barium contrast, a colloidal suspension of barium sulfate in water, is the medium of choice for esophagography. Varying densities, based on weight per volume, are used depending on what phase of the examination is being performed. Commercially available preparations contain flavors and such additives as aluminum hydroxide, sorbitol, and methylcellulose. Water-soluble iodinated contrast, such as Gastrograffin, may be used as an alternative to barium contrast when there is concern for perforation or leak, as this medium is readily absorbed into mediastinal tissue or body cavities. However, there is suboptimal mucosal coating and leak identification due to this rapid reabsorption, leading to false-negative rates of up to 25-30%. If there is high suspicion of a leak or perforation, a thin (1ow density) barium esophagram is subsequently performed. Isoosmolar or low-osmolar contrast or barium agents should be considered if there is concern for aspiration or an airway fistula. A double-contrast study, or air-contrast study, involves gaseous distension of the esophagus in addition to administration of high-density contrast. Effervescent tablets or granules that rapidly release CO2 are used to induce this distension, which improves the ability to detect mucosal abnormalities. Double-contrast is contraindicated following foregut surgery or trauma. A single contrast study implies only contrast is used.
Barium Esophagram: Patients should be NPO for a minimum of 2 hours prior to the study. A complete evaluation includes multiple phases to investigate various functional and morphologic abnormalities. There is institutional variance in what phases are included, as well as the order and manner in which they are performed. The exam should be tailored to the clinical situation and patient condition. Typically, a 250cc volume of contrast is swallowed in 45 seconds. Timed spot films are taken after ingestion in a variety of positions, capturing images which include the pharynx to GEJ and GEJ to stomach. Normally, the esophagus should empty this contrast volume in less than 1 minute.
Procedure:
A contrast esophagram includes multiple phases such as a timed barium swallow, upright and semiprone phases, motility phase, provocative maneuvers, solid food phase, and oropharyngeal phase. The exam is typically started in the upright position with double contrast views. Most gross abnormalities can be diagnosed in this initial phase. Images should be obtained with the esophagus both distended and collapsed after the swallowing of high-density barium contrast. The patient may be asked to turn 360 degrees to allow coating of the stomach before imaging.
Next, low-density contrast is swallowed to assess motility with the patient in the prone and oblique positions. This positioning excludes gravity from interfering with clearance. With the patient in the same position, low-density contrast is rapidly swallowed to maximally distend the esophagus. This allows imaging of strictures and rings that may have been too subtle to notice during the upright, double-contrast phase. Type 1, sliding hernias that were not noted on the upright views can also now be identified. The presence of GER is then assessed. The patient is imaged to check if the contrast has cleared the esophagus. If contrast remains, the patient may be repositioned in a more upright position to facilitate clearance. Once the contrast has passed, the patient is placed supine and the esophagus is imaged. Any contrast within the esophageal lumen signifies reflux. Additional "provocative maneuvers" that increase intraabdominal pressure (i.e. Valsalva, cough, leg raise, etc.) may be used to induce reflux. Finally, a self disintegrating barium tablet of predetermined size (usually 13 mm) or other barium-coated solid foods are used to again evaluate for strictures. Barium paste may be combined with solid food to investigate complaints of dysphagia prompted by certain consistencies of food.
An oropharyngeal phase may be added prior to the initial upright, double-contrast phase to assess the oral and pharyngeal phases of swallowing if there is a concern for aspiration. A modified barium swallow involves video recording to dynamically evaluate the swallowing mechanism. Alternatively, a modified barium swallow is performed with the assistance of a speech therapist. The patient is given items of varying consistency (i.e. barium pudding) to evaluate swallowing of solids or semisolids. Compensatory maneuvers for preventing aspiration or improving motor function can also be assessed.
Interpretation:
Being familiar with how the evaluation is carried out will aid in interpretation of contrast esophagrams. Noting patient position therefore will assist in determining what is being focused on in that phase of the examination. To assess for· patient position, look for the position of the spine and how the fundus is filling. Spine position allows distinguishing between sagittal, lateral, and oblique views. An air-fluid level ·will be seen in the esophagus when the patient is upright. Due its posterior location, the fundus fills with contrast in the supine position and air in prone position. Careful attention should be paid to the diaphragm at the esophageal hiatus to evaluate for hiatal hernias. Finally, motility can only be assessed in real-time, not on review of post-procedural images. Normal peristalsis appears as a propagating waveform completely obliterating the lumen distal and proximal to the barium bolus at a speed of 2-4 cm/s. With normal motility, a single bolus should traverse the entire length of the esophagus in 6 to 8 seconds. Finally, it is critical to that interpretation of contrast esophagraphy is considered in conjunction with clinical symptoms, upper endoscopy, and CT imaging. The motility phase of esophagrams can be particularly helpful in complementing manometry studies.
This is a revision and update from the previous edition of the TSRA Primer in Cardiothoracic Surgery written by Desmond D’Souza, MD
Post-Esophagectomy Care
Introduction:
Postoperative management after esophagectomy has not been standardized and vast variability exists in management approaches. However, it is known that this procedure is associated with significant morbidity and mortality.
Patients undergoing esophagectomy are often elderly, malnourished, and have significant comorbid disease. Therefore, postoperative care following esophagectomy is of paramount importance if excellent results are to be expected. A systematic approach to managing these patients ensures optimal outcomes and timely discharge. This chapter focuses on key points of early postoperative care.
Labs/Investigations/Orders:
Routine labs (CBC, BMP, magnesium and phosphate levels, PT/INR, ABG/lactate) and a CXR should be ordered in the immediate postoperative period. Valuable information may be obtained from the CXR, including NGT position, endotracheal tube depth (if patient is intubated), chest tube and drain position, size, and position of conduit in the chest, evidence of bleeding, etc. Daily labs and CXR are useful while the patient remains in the ICU. Once on the regular floor clinical discretion will dictate laboratory investigations.
Common postoperative care includes diligent monitoring of ins/outs and vital signs, chest tube, nasogastric tube and jejunostomy tube management. Once extubated, patients are often encouraged to get out of bed to the chair and ambulate with assistance. The head of the bed should be > 30 degrees to avoid aspiration.
Routine monitoring of nutritional labs (albumin, prealbumin) maybe warranted for malnourished patients or those with a prolonged hospital course. Patients are initially NPO and medications are typically crushed until a solid diet is resumed. Most medication can be delivered intravenously or via a feeding tube, however it is advised to avoid placing crushed medications down small-bore feeding tubes, which commonly leads to occlusion. Narcotics and a postoperative sedentary state commonly contribute to postoperative ileus, which in turn can adversely affect tolerance to enteral feeds and increases risk for aspiration.
All patients are placed on an aggressive bowel regimen. Electrolytes are closely monitored and repleted. Perioperative antibiotics are discontinued after 24 hours. Prophylactic dosing of heparin or enoxaparin are most commonly used for DVT prophylaxis. Bilateral lower extremity sequential compression devices are also commonly used. Early ambulation is encouraged, and physical/occupational therapy should be consulted.
IV fluids are discontinued once tube feeds are at goal. Depending on center specific protocols, a contrast esophagram may be obtained prior to starting a patient on a clear liquid diet or drain removal, while others may obtain esophagrams only if clinically warranted. Often, the post-esophagectomy diet resembles that of a Nissen clear liquid diet.
Consultations to ancillary services is also critical for successful rehabilitation in the postoperative period. Routinely consults are placed for physical and occupational therapy, nutrition to discuss post-esophagectomy diet, respiratory therapy, and home health referral to arrange for home tube feeds and nursing visits.
Pain:
Adequate pain control is essential following esophagectomy, regardless of approach. Multiple complications can be avoided by promoting aggressive pulmonary toilet and early ambulation, both of which are facilitated by effective pain management. Epidural analgesia is considered by many as the gold standard for management of postoperative pain. However, a dedicated pain management team is needed to avoid unnecessary hypotension associated with epidurals, as any hypotension in the early postoperative period can lead to hypoperfusion of the conduit with resulting increased risk of leak or necrosis.
Other options include IV PCA (patient-controlled analgesia) and ON-Q® pain catheters. Ketorolac and IV acetaminophen are also effective adjuncts to narcotics in those free of renal or liver disease. Narcotics given in the form of an elixir can be administered through a feeding tube without risk of obstructing the tube.
Blood Pressure Management:
The conduit is most commonly based on a single arterial pedicle (right gastroepiploic artery). This tenuous blood supply is very sensitive to vasoconstriction, justifying adamant avoidance of pressors both intra- and postoperatively. Unlike pulmonary procedures where patients are kept on the dryer side, patients undergoing esophagectomy should be aggressively fluid resuscitated to avoid the use of pressors but not overly fluid overloaded to avoid edema and undue pressure on the anastomosis. As stated previously, if epidurals are present, they should be decreased or discontinued if hypotension becomes an issue.
If massive volume resuscitation is required, consideration should be given to supporting the patient on the ventilator if there is concern for resulting pulmonary congestion. In the early postoperative period, maintenance of conduit perfusion takes precedence. Even transient periods of hypotension in the early postoperative period may be enough to cause conduit hypoperfusion and lead one down the pathway resulting in anastomotic leak or conduit necrosis.
Pulmonary Care:
Pulmonary morbidity compromises a large portion of postoperative complications following esophagectomy. Patients should be started on incentive spirometry 10x/hour once they are extubated and following commands. Patients must be encouraged to cough and deep breath, highlighting the importance of good pain control. If pulmonary toilet is inadequate, therapeutic bronchoscopy may help to minimize the risk of atelectasis and/or pneumonia. Similar to hypotension, hypoxia in the early postoperative period increases the risk of conduit ischemia.
Any evidence of hypoxia should prompt serious consideration to reintubate. Patients should be on aspiration precautions with the head of the bed elevated at least 30 degrees at all times. After esophagectomy, there is no longer an anatomic barrier to reflux, and patients are prone to aspiration when laying flat. This is often overlooked when patients are reintubated or are taken to the OR for subsequent procedures. Hoarseness, a weak cough, or aspiration should raise the suspicion for recurrent laryngeal nerve injury. An ENT consultation is then warranted to evaluate the vocal cords and possible cord medialization.
Tubes/Drains:
A NGT is crucial in the early postoperative period to avoid conduit distention, vomiting and aspiration. Conduit distension can lead to hypoperfusion of the conduit. Suctioning of proximal secretions also protects the anastomosis. The location of the tip of the NGT is somewhat variable, as some choose to leave it just above or at the level of the anastomosis, while others leave it at the level of the hiatus. Regardless, position should be checked on the immediate postoperative film with prompt repositioning at the desired level if needed.
It is not unusual to secure the NGT to the nose with a stitch or a nasal bridle. The NGT is placed to low intermittent or continuous wall suction initially and patency must be check frequently, which can be facilitated by routine flushes. It is helpful to place a sign at the head of the bed stating, "Do not manipulate NGT". Should the NGT fall out, it is ill-advised to reinsert it blindly, as this can do more harm by disrupting the anastomosis. It is safest to replace the NGT under endoscopic guidance with the assistance of an experienced surgeon.
A jejunostomy tube (J-tube) may be placed pre- or intra-operatively and allows early distal enteral feeding. The type and diameter of these feeding tubes is variable. The J-tube site should be checked daily to ensure patency, facilitated by scheduled flushings, and to ensure that anchoring sutures are intact.
Even with diligent surveillance of feeding tubes, some will fall out. It then becomes important to know when the tube was placed. If placed preoperatively, the tract is likely established and reinsertion can be performed at the bedside, followed by a water-soluble contrast tube study to confirm position. J -tubes placed at the time of resection are unlikely to have developed a mature tract and should not be reinserted blindly. In this case, it is recommended that the tube be reinserted over a wire under fluoroscopy. The J tube site should also be monitored for signs of local infection. Peritoneal signs should prompt investigation of a possible leak from the j-tube site, bowel obstruction from an internal hernia or twisting of the loop of jejunum that was brought up for the tube, or bowel injury.
For those patients undergoing a thoracic approach, a chest tube(s) will invariably be placed. These are initially placed to -20 cm H2O wall suction and changed to water seal if there is no air leak, and the patient is off the ventilator. Chest tubes are typically removed when drainage is less than 100-150 cc/day. Some choose to keep the chest tube in place until a barium swallow has ruled out a leak if an intrathoracic anastomosis has been performed. As with other thoracic procedures, there is significant variability in how chest tubes are managed. Other drains may be placed in the abdomen, chest, or neck. These are typically placed to bulb suction. Loss of suction should raise suspicion for a possible anastomotic leak and should be further investigated. Drains may be removed if output appears benign and has decreased to a predetermined level. However, some choose a more conservative route and will leave the drains in place until they are seen as an outpatient for their follow up appointment, particularly if the drain is placed near the anastomosis, as many leaks will present in a delayed fashion. Prior to discharge, the drains are "cracked" (pulled back 1-2 centimeters) to allow the drain tract to gradually collapse down. The most important aspect of drain management is the monitoring of the quantity and nature of drainage, both through and around the tubes. Drain output often yields clues to bleeding, leaks, chylothorax, etc. If there is a question as to the origin of drain output, the fluid can be sent for amylase, bilirubin, hematocrit, triglycerides, etc. to further clarify the source.
Nutrition:
Enteral feedings may be started as early as postoperative day 1, while some choose to wait until evidence of return of bowel function. Type and concentration of tube feeds, as well as the manner in which they are advanced, varies by institution. Regardless, it is important to monitor the patient for signs of abdominal distension or intolerance, at which point the feeds should be stopped and the feeding tube placed to gravity. For those without feeding tubes or those not tolerating feeds, consideration should be given to parenteral nutrition if the patient remains NPO for more than a week. Diets are advanced slowly, starting with low volumes of clear liquids and advancing over a period of days to weeks. Supplementation with tube feedings should be continued as the diet is advanced until adequate calories are taken by mouth.
Conclusion:
These key points should serve as adjunct to clinical decision making and guide your thought process in formulating a postoperative treatment plan for your esophagectomy patients. Postoperative complications are discussed in the following chapter; however, the key to management of these complications is prompt diagnosis, facilitated by optimal postoperative surveillance.