General: Some procedures for venous thromboembolic disease, such as IVC filter placement, can be safely performed without anesthesia involvement.
Patients who may benefit from anesthesia care team involvement, include patients:•With high ASA classification.
•At-risk for respiratory or hemodynamic decompensation.
•Who are unable to tolerate awake procedure or supine position for a prolonged period of time.
•With procedures that are anticipated to be technically complex.
Postoperative pain for venous thromboembolic disease is commonly well-controlled with the intraoperatively administered local anesthetic and over-the-counter non-opioid analgesics, such as Acetaminophen.
a.Optimization and Risk Assessment
The acuity with which a venous thromboembolic disease presents can range from a stable patient awaiting a “semi-elective” procedure to a highly unstable patient requiring hemodynamic support and mechanical ventilation.
Consequently, the perioperative anesthesia process should be meticulous and include identifying potential risk factors, with particular attention paid to h/o hypercoagulable state, including h/o DVT, PE, pulmonary HTN due to potential chronic embolic burden (RV function), and anticoagulation.
b.Anesthesia Management
i) Anesthesia Techniques
MAC is preferred.
LA +/- sedation is the technique most commonly used for venous thromboembolic disease interventions.
Sedation is commonly provided with benzodiazepine, propofol, and/or dexmedetomidine infusion. Notably,avoidance of perioperativebenzodiazepines has been recommended to reduce the risk of postoperativedelirium.110Dexmedetomidine, with its lack of respiratory depression, may be an attractive alternative. When used in high doses, however, hypotension and/or bradycardia resulting from Dexmedetomidine may outlast its sedative effects leading to prolonged stay in the PACU.
Opioids may be added for analgesia/sedation as well.
General anesthesia may be required in select patients who are unable to tolerate sedation, be supine for prolonged period of time, or who require a complex surgical intervention. Patients with high acuity (e.g., hypoxia or hypercarbia) and/or co-morbid burden may need endotracheal tube placement for mechanical ventilation. However, general anesthesia (or even deep sedation with propofol) can lead to hemodynamic collapse in unstable patients with PE. Therefore, in unstable patients with PE general anesthesia induction should either be avoided or conducted with great caution, with ECMO stand-by, if available.
ii) Monitoring and Access
All patients require the standard mandated by the American Society of Anesthesiologists including oxygenation (peripheral O2S), ventilation (CO2 monitor), circulation (ECG and BP) and temperature monitoring.67
In addition, all patients need an adequate IV-access and continuous oxygen supply.
•Indwelling Arterial Catheter: May be considered in patient with cardiac, pulmonary, renal, or metabolic conditions requiring continuous hemodynamic monitoring and/or blood sampling.
•Depth of Anesthesia Monitor (EEG, or EEG-based device):May be considered in elderly patients at risk, as increased anesthesia depth has been linked with postoperative cognitive decline and delirium.127, 128
•Brain Oxygenation:Monitoring usingcerebral oximetry(similar principle as peripheral pulse oximetry) may be consideredinpatients with history of or at risk for stroke.129
•Cardiac Output Monitor: May be considered in those with tenuous cardio-pulmonary status or at risk of hemodynamic decompensation.
iii) Intraoperative Concerns
In most patients the intraoperative course is uneventful. However, hypotension, kidney injury, and/or hypothermia may ensue.
•Patients with Pulmonary Hypertension:For example, due to thromboembolic burden, should be identified in effort to prevent acute intraoperative right heart failure/ischemia (e.g., due to acute embolus or intraoperative hypercarbia leading to increase in right heart pressures). The differential diagnosis of an intraoperative hemodynamic collapse (code blue) should include acute RV ischemia/failure. Notably, the reverse Trendelenburg and not the Trendelenburg position may help unload right heart chamber. In patients with pronounced hypotension refractory to other therapies, emergent use of VA-ECMO should be considered.142Bradycardia can also occur with rheolytic thrombectomy using the Angiojet device. Although often asymptomatic and self-resolving, it can lead to cardiac compromise in elderly patients with existing coronary disease and should be treated accordingly.
•Kidney Injury:While many different agents have been studied with varying success, only fluid loading (while avoidingovert volume overload) has been consistently reported to be associated with better renal outcomes. This is particularly important when rheolytic thrombectomy with the Angiojet device is performed, given the risk of heme pigment nephropathy from intravascular hemolysis.
•Hypothermia:In the elderly, hypothermia could be detrimental. Thermoregulation becomes impaired with aging.69, 70Thus, proactive methods for temperature regulation should be aggressively utilized.7
c. General and Procedure-Specific Concerns
General intraoperative concerns: Skin preparation (CHG wipe timeout for three minutes to dry), Foley placed by trained staff, shaving performed with clippers, normothermia.
General:
•Perioperative antibiotics are not routinely administered unless intravenous/intraarterial catheters are left in place for lytic infusion.
•Venous access should be performed under ultrasound guidance regardless of site (femoral, popliteal, jugular or other)
•Contrast volume should be minimized in patients with renal insufficiency by using dilute contrast or CO2 angiography to avoid Postcontrast acute kidney injury. Intravascular ultrasound can further decrease use of contrast and is the preferred modality for identifying venous outflow obstruction and sizing of venous stents.
•Full dose anticoagulation is administered prior to intervention (balloon angioplasty/stenting/mechanical thrombectomy) and ACT is maintained above 200s.
•For initiation/continuation of catheter-directed thrombolysis, the sheaths and catheters should be secured to the patient to prevent dislodgement during transportation.
•For initiation/continuation of catheter-directed thrombolysis, all the infusion lines should be clearly labeled with the respective medication for continuation of care.
•Patients Undergoing Catheter-directed Thrombolysis
•General:
- Administer low-dose heparin through the access sheaths and avoid full anticoagulation during the infusion of thrombolytic agent to minimize the risk of bleeding.
- Patients are on bed rest and should not ambulate.
- Patients can resume diet after the procedure but should be kept NPO subsequently for enough time in preparation for follow up procedure.
•Monitoring:
•Patient should be admitted to a monitored unit or intensive care unit per hospital protocol.
•Patients should be assessed at least every 2-3 hours for bleeding at the access site and remotely, extremity perfusion, and change in mental status.
•Patients should have labs (CBC, prothrombin time [PT], partial thromboplastin time [PTT], INR, and fibrinogen) checked periodically during the day per local protocol.
