Successful spinal anaesthesia for caesarean section in an African patient with Takayasu’s arteritis

Takayasu's arteritis (TA) is a rare chronic inflammatory disease affecting mainly the aorta and its main branches. We report a case of a 24-year-old primigravida, an African patient, with TA planned for caesarean section at 37 weeks of gestation. Clinically, she has involvement of aortic arch and its branches and abdominal aorta. She underwent caesarean section and delivered an alive baby boy under successful spinal anaesthesia with insignificant complications. Although it is rare in the African continent, anesthesiologists should be up-to-date with the knowledge of perioperative anesthetic management of TA in pregnant cases requiring operative delivery.

TA usually affects aorta and its main branches commonly: carotid, subclavian and renal arteries [1][2][3][4][5][6][7][8][9][10]. TA affects more women than men with a ratio ranging from 4:1to 8:1 [2-4, 10, 11]. The peak incidence is in the 2 nd -3 rd decades [5]. It is common in Japan [1], Asia and South America, and less common in Europe and North America [4][5][6]10]. Intimal infiltration by lymphocytes and other inflammatory cells results in the replacement of vessel wall elastic tissue by fibrous tissue with subsequent formation of stenosis, occlusion and aneurysm [1,5]. The major cause of hypertension in TA is renovascular but it can result from an abnormal function of the carotid and aortic sinus baroreceptors and/or reduced elasticity and a marked narrowing of the aorta and major arteries [8]. Clinical symptoms depend on the distribution of the involved vasculature and ischemic disturbance of the organs affected. This may result in claudication, ischemic pain and fatigue of the limbs, and carotid arteries may give headache, vertigo, syncope, convulsions, transient hemiplegia, aphasia, and visual disturbance; renal artery involvement may cause hypertension and some patients may progress to aortic insufficiency and congestive heart failure [1,2,5,9]. Physical findings depends on the affected artery and include high blood pressure and reduction or loss of palpable pulses in the neck and limbs [7,9]. Pulmonary involvement leads to pulmonary hypertension [9]. Management of TA involves corticosteroid and other immunosuppressive agents [1,5,10,11]. Some cases of TA may require further treatment in the form of angioplasty or surgical correction [4,5,7,10]. The commonest cause of death in TA are heart failure, myocardial infarction (MI) and stroke [5,11]. Fatal complications during pregnancy include aortic aneurysm rupture and cerebral haemorrhage [10].
Anaesthesia in TA is complicated by uncontrolled hypertension leading to end organ dysfunction, stenosis of major blood vessels affecting regional circulation, and difficulties in the monitoring of arterial blood pressure [8]. The initial manifestation of TA may occur during pregnancy [4]. The effect of pregnancy on TA is unclear [1,5,7,9]. But in 60-90% of cases hypertensive complications including preeclampsia, exacerbated chronic hypertension, miscarriage or fetal loss are reported [5][6][7]. Reports on spinal anaesthesia for caesarean section for the management of patients with TA in African continent is almost non-existent. We are presenting a case of TA pregnant patient who successfully delivered by caesarean section using spinal anaesthesia.

Patient and observation
We are presenting a 24-year-old African premegravida who was
It is common in Japan, [1] Asia and South America, and less common in Europe and North America [4][5][6]10]. Although TA is reported in Africa, reports in association with pregnancy and spinal anesthesia is limited. American college of Rheumatology diagnostic criteria for TA: age of onset 40 or less, claudication, aortic or subclavian bruits, decreases brachial pulses, difference more than 10mmHg between right and left arm systolic pressure and angiographic findings (irregular intimal surface, stenosis of the aorta or its branches, poststenotic dilatations, secular aneurysms or the typical narrowed "rat tail" appearance) [1] of hemodynamically significant lesions in the aorta or its major branches [3,4,7,10], the presence of at least three of the above criteria confirms the diagnosis with 97% specificity and 92% sensitivity [1,4]. Our patient is less than 40 years, has carotid bruit and a difference of more than 10mmHg in systolic blood pressure between right and Our patient having hypertension will be in group IIb. For group IIb and III, operative delivery is preferred with the aim of avoiding increased blood volume and hence arterial pressure which can occur during uterine contraction [5,7] . Our patient being IIb and having oligohydramnios and IUGR operative delivery was planned.
Preoperative evaluation involves identifying the distribution of affected arteries, degree of organ involvement with special attention to cardiac, pulmonary, renal and cerebral function in addition to drugs used for the treatment of TA [2]. Chronic use of corticosteroids could lead to suppression of endogenous corticosteroids release [7], hence our patient was given 100mg of hydrocortisone preoperatively. Invasive BP monitoring is advised in patients with BP measurement difficulty to obtain in any extremity and if rapid fluctuation in BP is anticipated [5][6][7]10], which is not the case in our patient.
In addition to pregnancy induced physiological changes anaesthetic management in TA takes compromised regional circulation into consideration [8,10,11]. The anaesthetic goal in a patient with TA is the maintenance of blood pressure during perioperative period [11,12]. Low dose regional anaesthesia (RA) combined with opioid causes less hemodynamic instability and allows easy monitoring of cerebral circulation [2,10,11]. Unlike general anaesthesia RA is associated with less risk of aspiration, pressure response during intubation and extubation which may aggravate hypertension and tachycardia leading to MI, Congestive heart failure (ccf) and intracranial hemorrhage [5,7,8,11]. RA may cause hypotension inducing cerebral, renal, intestinal or uterine ischemia, [2,6,8,10] but can be minimized by pre-anaesthetic volume expansion. Spinal anaesthesia hypotension can be corrected by generous IV fluid and by placing the patient in reverse Trendelenburg position [2].
Different doses of bupivacaine and fentanyl combination were reported with successful including 6.5 mg hyperbaric bupivacaine and 25 µg fentanyl [8]. We used 7.5mg of 0.5% hyperbaric bupivacaine combined with 20µg fentanyl successfully. Most TA patients need monitoring particularly for the first 24 hours following operative delivery under spinal anesthesia as about 60% of patients develop postoperative problems following inadequate control of arterial pressure including heart failure or fatal stroke in a small group of patients [5,10]. Our patient's condition was optimal in recovery and she was transferred to the post-natal ward for regular BP monitoring.
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Conclusion
Blood pressure control during pregnancy, delivery and immediate post delivery period is an important step in reducing obstetric morbidity in this group of patients. Spinal anesthesia allows easy monitoring of cerebral perfusion. Although TA is very rare on the Africa continent, anesthesiologists should be up-to-date on the perioperative anesthetic management of TA.