Cardiovascular Considerations in Anesthetic Management for a Patient With Antiphospholipid Syndrome and Decreased Cardiac Function: A Case Study
This case report describes the prolonged general anesthetic management of a 41-year-old woman with antiphospholipid syndrome (APS), systemic lupus erythematosus, and previously undiagnosed decreased cardiac function who underwent planned partial resection of the left tongue, tracheostomy, neck dissection, and pedicled flap reconstruction. This was immediately followed by emergent surgery to salvage the flap, and 1 month later, revision of the soft tissue flap was performed. A preoperative echocardiogram was performed because of her various risk factors, which identified lateral wall hypokinesis and reduced left ventricular ejection fraction of 40%, despite no known cardiovascular disease. However, cardiology consult determined no additional treatment was needed before the surgery. Multiple antithrombotic strategies were used, including elastic stockings, intermittent pneumatic compression devises, and heparin bridging. During the general anesthetic, stroke volume variation (SVV) was used to assess cardiac function and guide fluid management. There were no signs of systemic thrombosis, although the free flap reconstruction was abandoned because of a thrombus in the vascular anastomosis. Cardiac function can deteriorate in APS patients because of coronary and/or microvascular thrombosis. Therefore, it is necessary to evaluate cardiac function, regardless of a known history of cardiovascular disease. Moreover, additional monitoring (ie, SVV) may be useful during prolonged general anesthetics for patients with APS and cardiac dysfunction.
Antiphospholipid syndrome (APS) is a rare systemic autoimmune disorder characterized by recurrent venous or arterial thrombosis and/or pregnancy morbidity due to the persistent presence of antiphospholipid antibodies that primarily target prothrombin and beta-2 glycoprotein I. APS is classified into 2 groups: primary and secondary depending on the absence or presence of another autoimmune disorder such as systemic lupus erythematosus, respectively. Deep vein thrombosis of the lower extremities is most common in cases of venous thrombus,1 and cerebral infarction comprises more than 90% of cases of arterial thrombus.2 Myocardial infarction in the absence of coronary stenosis has also been reported in patients with APS, due to either coronary or microvascular thrombus formation.3–6 Anticoagulation therapy with warfarin is considered the most effective treatment, and concomitant antiplatelet therapy (eg, aspirin, ticlopidine) is also used.7 Furthermore, infection, invasive surgical procedures, and general anesthesia are known potential causes for catastrophic APS in which a patient presents with multiorgan failure resulting from multiple thrombi involving various systems or organs throughout the body.8 It has been reported that the mortality rate reaches 40–50% when this condition develops.9
There are several articles that discuss cardiovascular concerns with APS.3–6,10,11 However, there are no reports in the dental literature of prolonged general anesthesia for APS patients that focus on the cardiovascular considerations and anesthetic management. Here, we report the treatment of an APS patient with previously undiagnosed decreased cardiac function who underwent multiple surgical procedures requiring extremely prolonged general anesthetics.
CASE PRESENTATION
A 41-year-old woman (139.6 cm, 57.4 kg, body mass index 29.5 kg/m2) previously diagnosed with a left tongue malignancy and metastases to the cervical lymph nodes was scheduled to undergo a planned lengthy general anesthetic for partial resection of the left tongue, neck dissection, tracheostomy, and reconstruction with a pedicled soft-tissue flap. She subsequently underwent 2 additional operations, 1 emergent and 1 a revision, both of which required prolonged general anesthesia within a month of the initial surgery. Specific details pertaining to the 3 general anesthetics and operations are presented in the Table.
The patient's medical history was significant for systemic lupus erythematosus, diagnosed at the age of 14, and APS, diagnosed following multiple recurrent thrombotic events that started at the age of 36 when she developed cerebral venous sinus thrombosis, which was successfully treated without sequelae using thrombolytic therapy. The patient then developed a deep vein thrombosis (DVT) in her left lower extremity 9 months prior to the planned tongue cancer surgery, after which she was started on anticoagulation therapy with warfarin. However, the warfarin was terminated by the patient's attending physician after 4 months, which led to a DVT recurrence a month later. Based on this history, the patient underwent further evaluation and was formally diagnosed with APS.
The patient also reported a history significant for complicated reflux esophagitis, gastric ulcers, osteoporosis, lumbar disc disease, and right-eye blindness following the onset of Stevens-Johnson syndrome. Her medications included the following: prednisolone 13 mg, warfarin 1.25 mg, aspirin 80 mg, rabeprazole 10 mg, sodium ferrous citrate 100 mg, sodium azulene sulfonate 1.5 g, sucralfate 1.2 g, and itopride 150 mg. She reported allergies to cyclophosphamide, ampiroxicam, minocycline, mackerel, and nickel. The patient denied drinking or smoking. She hardly exercised because of her right-eye blindness but denied any history of chest pain.
Preoperative coagulation studies for the initial surgery revealed a prolonged activated partial thromboplastin time of 46.0 seconds and a prolonged prothrombin time/international normalized ratio of 1.97. The D-dimer value was within normal limits (Table). A routine preoperative electrocardiogram was obtained because of her multiple medical comorbidities, which was notable for complete right bundle branch block. She also had a preoperative echocardiogram due to multiple medical comorbidities, which detected lateral wall hypokinesis and a reduced left ventricular ejection fraction (40%), despite no known cardiovascular disease. The planned operation was subsequently postponed until a more thorough cardiovascular evaluation could be completed.
The patient was evaluated by a cardiologist and underwent a cardiac catheterization and coronary angiography, which revealed hypoplasia of the left circumflex branch and 75% stenosis of the left anterior descending coronary artery. Stenosis was not noted in any other coronary arteries. Her cardiologists suspected the stenotic lesion could be attributed to (1) myocardial thrombosis due to APS, (2) sequela from systemic lupus erythematosus, or (3) sequelae from prolonged steroid use. However, the exact cause of the abnormal findings remained unclear. According to the cardiologists, reperfusion therapy (ie, a coronary stent) was deemed unnecessary, and no additional treatment was recommended prior to surgery.
First Surgery: Planned
Under the direction of the cardiac surgeon, who was managing the patient's previous DVTs, the patient was bridged from oral warfarin to continuous unfractionated heparin, which was started 5 days before and discontinued 3 hours before the surgery. Noninvasive antithrombotic therapy consisting of elastic stockings and intermittent pneumatic compression devices was also used throughout the perioperative period. Aspirin administration was continued as well, as the attending oral surgeon deemed adequate hemostasis likely achievable despite its continued use.
Because of poor peripheral venous access, a central venous catheter was placed in the right internal jugular vein preoperatively. General anesthesia was induced with fentanyl, propofol, and rocuronium. The patient was initially intubated with an oral endotracheal tube (size 7) that was converted to a tracheostomy tube (size 8) during the surgery. Anesthesia was maintained using fentanyl and infusions of propofol and remifentanil during most of the procedure. The propofol infusion was discontinued after switching to sevoflurane a few hours before the end of the procedure to avoid delayed emergence (Table).
To monitor hemodynamics and guide fluid management, stroke volume variation (SVV), via an arterial pressure–based cardiac output measuring device (FloTrac/Vigileo System), and central venous pressure (CVP) were assessed intraoperatively. Intraoperative fluids were adjusted to maintain an SVV no higher than 15%, a CVP of 4–8 mm Hg, and urinary output >1 mL/kg per hour. Intraoperatively, the patient remained hemodynamically stable throughout the entire procedure, with only a mild decrease (85–89 mm Hg) in systolic blood pressure observed. To maintain the patient's systolic blood pressure within her normal range of 90–110 mm Hg, intravenous ephedrine (5-mg bolus; 20 mg total) was administered whenever her systolic blood pressure fell below 90 mm Hg. The patient was mechanically ventilated using a tidal volume of 8–9 mL/kg, requiring no positive end-expiratory pressure. Her respiratory status remained stable throughout the perioperative period, with no findings suggestive of impaired cardiac function or pulmonary embolism.
Approximately 10 minutes after discontinuing the anesthetic agents, the patient rapidly emerged from the prolonged general anesthetic (∼15 hours) with the tracheostomy tube in place, and no noteworthy neurological findings were observed. Postoperatively, a Doppler ultrasound probe was used to verify blood flow to ensure adequate perfusion of the soft-tissue flap, in addition to frequent blood pressure and CVP measurements. Heparin was resumed 30 minutes after returning to the ward. Upon observation, there were no signs suggestive of pulmonary embolism, although the 2 peripheral intravenous catheters in the left dorsal and antebrachial veins were notedly occluded until 5 hours after the continuous heparin administration began.
Second Surgery: Emergent
The next day, the muscle flap lost perfusion, prompting emergency surgery to reestablish blood flow and salvage the flap. Heparin administration was discontinued 1 hour before the emergency procedure. The surgery took ∼4.5 hours, and the general anesthetic closely mirrored that of the initial surgery, with the noted use of methoxamine and dopamine along with ephedrine (Table). Heparin was restarted at a higher dose 1 hour after she returned to the ward, but the peripheral intravenous catheters obtained intraoperatively became reoccluded by the next day.
Third Surgery: Revision
Approximately 1 month later, the patient underwent reconstruction using a left radial forearm free flap due to deterioration of the pedicled flap. Again, the patient's anesthetic management was similar to the previous 2 general anesthetics and proceeded without incident. Intraoperative vasoconstrictors consisting of ephedrine and dopamine were again administered (Table). There were no signs of pulmonary embolism or any further decline in cardiac function. However, the surgical procedure was very lengthy (∼21.5 hours) and difficult because of an arterial thrombus in the vascular anastomosis, despite the systemic administration of heparin. Therefore, reconstruction using the free flap was abandoned, and the large pectoral muscle flap was revised surgically with skin grafts.
DISCUSSION
Thrombosis is the most commonly noted problem in patients with APS because the recurrence rate is as high as 4–7%, even when antithrombotic therapy is used.7,8 Particular care must be taken during the perioperative period, as patients may become hypercoagulable due to surgical stress or infection.9 Even though several antithrombotic strategies were used while managing this patient, several localized thrombotic occurrences were encountered, including multiple occlusions of peripheral veins and an arterial thrombus in the vascular anastomosis of the free flap. However, there was no objective evidence to show that APS was directly related to these episodes, and no systemic complications attributed to thrombosis were noted (eg, pulmonary embolism, cerebral or myocardial infarction, catastrophic APS). Nevertheless, additional care to prevent impaired local blood flow to the soft-tissue flaps may be needed, along with precautions against cerebral infarction and coronary thrombosis.
As previously described, 90% of arterial thromboses in APS patients result in cerebral infarction, although some patients have developed myocardial infarction. According to the European Forum on Antiphospholipid Antibodies, 5.5% of a total cohort of 1000 patients with APS suffered from myocardial infarction.11 Sacre et al6 reported that gadolinium enhancement of cardiac magnetic resonance imaging performed on 27 APS patients without a history of coronary artery disease identified 8 patients (29.6%) who presented with findings suggestive of a myocardial infarction, which was 7 times higher than in the control group. Ebina et al3 reported that premature ventricular contractions and abnormal Q waves were observed in the preoperative electrocardiogram of an APS patient and that further examination revealed the presence of findings suggestive of an old myocardial infarction. However, no clear coronary vessel stenosis or occlusion was noted. Therefore, it was determined that there was a high possibility of transient coronary thrombosis due to APS. In addition, there are a few reports of myocardial microthrombus and resulting cardiac dysfunction in patients with APS.4,5 The patient in this case had no history of cardiovascular complications and denied any subjective symptoms, such as chest pain. However, her preoperative echocardiogram demonstrated lateral wall hypokinesis and reduced left ventricular ejection fraction (40%). Although the exact cause was not elucidated, it was thought to be most likely related to thrombotic sequela associated with APS. Therefore, it is necessary to consider a thorough preoperative cardiac evaluation for all APS patients in collaboration with a cardiologist, regardless of symptoms or findings suggestive of underlying cardiovascular disease.
The risk of venous thrombosis in this patient was considered high because of the following factors: (1) history of previous DVT in the lower extremities and a cerebral venous sinus thrombus, (2) history of DVT recurrence after discontinuation of warfarin, (3) the planned surgical procedures were likely to require extremely prolonged periods of general anesthesia, (4) the required use of a tourniquet to harvest the free flap in the third surgery, and (5) the need for prolonged posture restrictions to ensure lack of tension on the free flap after the second operation.
For this patient with deteriorated cardiac function, placement of a central venous line was essential for CVP measurement to guide fluid management and to facilitate the administration of drugs including the potent vasopressors. However, it has been previously reported that central line placement in the femoral vein is associated with an increased risk of thrombus development compared with placement in other locations.10 Therefore, we elected to place the line in the right internal jugular vein for the first and second surgeries and in the right anticubital vein for the third surgery.
While dehydration may increase the risk of thrombus formation, excessive fluid volume can also be detrimental, particularly for a patient with coexisting cardiovascular dysfunction. Therefore, we felt that careful monitoring with SVV, in addition to urinary output and CVP, was important for this patient. SVV provides information on dynamic changes in cardiac function based on fluctuations in arterial blood pressure relative to respiratory patterns. It can be measured by using an arterial pressure–based cardiac output measuring device (FloTrac/Vigileo System). It appears that SVV monitoring was effective in the strict fluid management of this patient, which helped reduce the risk of (1) thrombus formation due to excessive blood loss and/or dehydration associated with prolonged operative times and (2) heart failure due to excessive fluid administration in a patient with existing cardiac dysfunction.
CONCLUSION
In summary, preoperatively evaluating cardiac function in all APS patients, regardless of a known history or findings suggestive of cardiovascular disease, is strongly recommended. In addition, for prolonged general anesthetics in patients with APS and impaired cardiac function, strict fluid management guided by SVV, urinary output, and CVP monitoring may be considered to avoid exacerbating any underlying cardiac dysfunction or potentiating the risk of an embolic or thrombotic occurrence.
Contributor Notes