Anesthetic management of a patient with congenital cyanotic heart anomaly for emergency surgery: A case report

Abstract

Among congenital cyanotic heart diseases (CHDs), situs inversus totalis with transposition of great vessels with a large ventricular septal defect (VSD) has a very low incidence of around 1 in 10,000. Hereby, we present a 16-year-old man with the aforementioned cardiac anomaly with cardiac arrhythmias, septic shock, and a history of road traffic accident-causing osteomyelitis of the left thigh requiring incision and drainage. The patient was admitted to the intensive care unit with a high-grade fever, narrow pulse pressure, and atrial fibrillation. The patient was operated on under general anesthesia with endotracheal intubation after optimization. Invasive monitoring, antiarrhythmics, and vasopressors were required intraoperatively, and surgery progressed uneventfully. Furthermore, the patient had undergone a series of debridements after 8 days, which were performed under regional anesthesia uneventfully. This case report represents a plan of action for perioperative anesthetic management and anticipates the difficulties for CHD patients in the course of surgery and subsequential prudence.

Introduction

Situs inversus totalis is a rare congenital condition when the thoracic and abdominal organs are mirrored.[1] A spectrum of laterality disturbances is caused by the failure to generate normal left-right asymmetry, which is a global defect of situs orientation. The complete reversal of normal organ position, including both the thoracic and abdominal organs, is called situs inversus totalis.[2] Although the precise cause is unknown, it is believed to be caused by a single incomplete penetration autosomal recessive gene.[3]

Clinical Findings

Patient information: A 16-year boy, with a history of fall from a bike 15 days ago and weighing 45 kg, presented with complaints of high-grade fever, pain, and swelling in the left lower limb.

He was pale and had central cyanosis and digital clubbing, a pulse rate of 120/min, which was irregularly irregular, noninvasive blood pressure of 90/60 mm Hg, cold extremities, oxygen saturation (SpO₂) of 82% with oxygen at 10 lit/min by non-rebreathing mask (NRM), and respiratory rate of more than 35 per min.

Diagnostic Assessment

Hematology testing showed a total leukocyte count (TLC) of >20000/cu.mm, hemoglobin (Hb) of 14.2 mg/dl, platelets of 1,04,000/cu.mm, and C-reactive protein of >219 mg/L. Renal and liver functions were within an acceptable range. Electrocardiography revealed an inversion of the electrical waves, T wave inversion in lead II, III and avf, ST segment elevation in V2,V3,V4,V5 and V6, and atrial fibrillation. An X-ray of the chest showed dextrocardia. His two-dimensional (2D) echo was suggestive of situs inversus with transposition of great vessels, a large ventricular septal defect (VSD), a large atrium with stump of interatrial septum close to the roof, a large ostium primum, a single large atrium, a large single atrioventricular valve with atrioventricular canal defect, a dilated pulmonary artery arising from the left ventricle, severe pulmonary hypertension, an aorta arising from the right ventricle, the left ventricle on the right side, and vice versa. Abdominal screening exhibited the Inferior vena cava to the left and the aorta to the right of the vertebral body. Ultrasound sonography (USG) of the abdomen and pelvis revealed situs inversus and splenomegaly. Preoperative arterial blood gas (ABG) (pH 7.47, pCO₂ 20.4 mm Hg, pO₂ 40 mm Hg, sO₂ 77.4%, HCO₃ 23.3 mmol/lit). Magnetic resonance imaging (MRI) of the left leg confirmed the diagnosis of emphysematous osteomyelitis of the left femur with associated cloaca formation, adjacent muscle abscess, and subcutaneous edema. Consequently, debridement and drainage of the left thigh were planned after the initial stabilization of the patient.

Therapy was initiated with inj. low molecular weight heparin 0.4 mg subcutaneous (SC), inj. furosemide 20 mg intravenous (IV), tab. bisoprolol 2.5 mg, and tab. amiodarone 200 mg.

Therapeutic Intervention

Relatives were counseled about the risk of anesthesia, and written consent was obtained. Preoperative vitals were heart rate (HR) of 96/min and irregular, blood pressure (BP) of 90/50 mm Hg with vasopressor support, and oxygen saturation (SpO₂) of 82% with oxygen by NRM at 10 lit/min. Invasive blood pressure and central venous cannulation were performed. After premedication with opioids, the patient was induced with inj. etomidate, inj. ketamine, and inj. vecuronium and intubated with cuffed ETT no. 7.5.

Sevoflurane, oxygen, and air were used to maintain a minimum alveolar concentration (MAC) of 1. Hemodynamic parameters were maintained within 20 percent of baseline, for which a higher rate of inj. noradrenaline infusion was required. End-tidal carbon dioxide was maintained between 30 and 35 mmHg. The temperature was maintained between 36.5 and 37.5 degrees Celsius. Blood loss was 600 ml, and more than 1.5 liters of pus was drained from a linear incision from mid-thigh to below the knee. Total urine output was 200 ml, and input was 1300 ml.

Follow-Up and Outcome

Elective mechanical ventilation was planned postoperatively in the intensive care unit (ICU) with an assist control mode of ventilation (tidal volume 325 ml, respiratory rate 22/min, FiO₂ 50%, positive end expiratory pressure 4 cm H₂O). Elective ventilation was continued for 48 hours. The amiodarone infusion was stopped after 24 hours, and noradrenaline was gradually tapered. The extubation was uneventful. Subsequently, the patient underwent debridement of the wound six times uneventfully under spinal anesthesia and peripheral regional blocks (USG-guided femoral block and popliteal block) for postoperative pain.

Discussion

Transposition of the great vessels is incompatible with survival unless additional lesions are present, which allow adequate mixing of oxygenated and deoxygenated blood. In our patient, TGA was associated with VSD, which facilitated this mixing.[4] Those patients who survive present with complications such as preexisting hypoxia and cyanosis, polycythemia, hypercoagulability, thrombotic complications, and coagulopathies.[3]

The most noteworthy challenges this patient had were TGA with VSD, severe pulmonary hypertension, and septic shock.

Sepsis is a clinical state that can cause profound dysregulation of the cardiovascular system (CVS). The bad effects of sepsis on CVS are not limited to the contractile function and/or ventricular relaxation, but they also extend to the electric function. Atrial fibrillation is among the most common arrhythmias found in septic patients.[5]

Factors contributing to substantial perioperative risk in children with unrepaired cyanotic heart disease (CHD) undergoing noncardiac surgery include the presence of congestive heart failure (CHF), pulmonary hypertension, cyanosis, and nature of the surgery. Hence, precursors to acidosis, including hypothermia, hypercarbia, and hypotension, should be avoided, as should nitrous oxide, and intracardiac shunting should be minimized, to prevent the worsening of pulmonary hypertension and CHF.[6]

Preoperative adequate hydration was maintained, and invasive lines were flushed to avoid air bubbles owing to a high risk of paradoxical embolism due to the presence of bidirectional shunts.[1]

SpO₂ and the amount of shunting of blood in TGA are impacted by the ratio of pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR). Increased pulmonary blood flow causes higher arterial SpO2 when PVR declines. However, as PVR rises, CHF improves at the expense of increased cyanosis, tachycardia, and hypotension. Thus, to achieve a balance between CHF and hypoxia, an anesthesiologist must adjust PVR and SVR using pharmacological and ventilatory techniques.[1] We started inj. noradrenaline infusion before induction and used titrated doses of inj. etomidate and inj. ketamine for induction of anesthesia, which enhanced arterial oxygenation and maintained systolic blood pressure between 90 and 100 mm of Hg intraoperatively.

Anesthesia was maintained with sevoflurane in 50% O₂+ 50%. The air-to-pulmonary blood flow ratio is unaltered, and left ventricular systolic function is maintained at 1 MAC. Urine output and blood loss were monitored and compensated with crystalloids and whole blood in equal measure.

The patient was electively ventilated for the next 48 hours and gradually weaned off. Subsequently, he underwent six surgeries for debridement, vacuum-assisted closure (VAC) dressing, and skin grafting, which progressed uneventfully with a unilateral subarachnoid block and peripheral lower limb blocks for postoperative pain.

Conclusion

The present case showcases that a comprehensive knowledge of pathophysiology in conjunction with meticulous planning is a prerequisite for anesthetic management of a patient with a complex CHD to reduce perioperative morbidity and mortality.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and that due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.