Klippel Trenaunay syndrome and the anaesthesiologist.

Sir,

We read with interest the article ‘Anaesthetic management of a neonate with Kasabach-Merritt syndrome.’[1] We would like to highlight a syndrome with known association to Kasabach-Merritt syndrome (KMS), namely Klippel Trenaunay Weber syndrome. Many anaesthetic concerns are common to both syndromes [Figure 1].

Figure 1

Gigantic left lower limb in Klippel Trenaunay syndrome

A 13-year-old boy with Klippel Trenaunay syndrome (KTS) was scheduled for left hip disarticulation in our hospital. Due to lymphohaemangiomatous malformation extending to the pelvis, his left lower limb had assumed gigantic proportions rendering him bedbound. Airway and systemic examinations were normal. Cardiology examination with echocardiogram ruled out high output cardiac failure. Blood investigations including coagulation profile were normal. After obtaining high-risk informed consent and ensuring availability of blood and blood products, he was taken up for surgery. His weight was 25 kg and pre-operative haemoglobin was 11.9 g/dl.

After preoxygenation, fentanyl 30 μg, propofol 75 mg, atracurium 12.5 mg was administered and endotracheal intubation performed with 6.5 mm cuffed endotracheal tube. Monitoring was established with standard monitors and intra-arterial line, subclavian central line for blood gas and central venous pressure. Anaesthesia was maintained with oxygen, nitrous oxide and 2% sevoflurane; 3 mg of morphine and 0.5 g of paracetamol infusion. Tranexamic acid 500 mg was administered as intravenous infusion in normal saline.

During the 3 hour surgery, 3000 ml blood loss occurred (145% of the child's blood volume). Intra-operatively, he was transfused 5 units of packed red blood cells (PRBCs), 4 units of fresh frozen plasma, 2 platelet concentrates and was administered 10 ml calcium gluconate. Intra-operative hypotension responded to volume replacement and low-dose dopamine infusion. Intra-operative arterial blood gas and urine output were normal. At the end of surgery, he was electively ventilated in the intensive care unit with morphine infusion for post-operative analgesia. Post-operative haemoglobin was 8 g/dl, platelets 45,000 mm-3, prothrombin time 1.16, calcium 6.4 mg/dl, magnesium 1.6 mg/dl. After transfusing 2 units of PRBCs (in view of ongoing blood loss in the surgical drains) and 2 units of platelet concentrates, correcting electrolyte imbalances with supplements of potassium, calcium and magnesium, and tapering dopamine, he was extubated the next day. Rest of the post-operative period was uneventful.

Klippel Trenaunay syndrome is a rare congenital malformation (incidence of 1 out of 27,500 live births) with a triad of venous malformations or varicose veins, cutaneous capillary malformations and bony or soft tissue hypertrophy in affected limbs.[23] The lung, trunk, gastrointestinal tract, neurovascular structures and the bladder may be involved with the presence of vascular malformations.[4]

Implications for the anaesthesiologist are many. Firstly, difficult intubation must be anticipated as patients may have facial anomalies, upper airway angiomas and soft tissue hypertrophy in the airway.[3] Secondly, the potential for massive intra-operative haemorrhage must be considered. In KTS, local intravascular coagulation occurs within the malformation, and distal flow has depletion of coagulation factors.[5] KTS is also often associated with disseminated intravascular coagulation and KMS (consumptive coagulopathy and thrombocytopenia).[3] The anaesthesiologist must, therefore, be vigilant with sufficient intravenous access, adequate blood product reserve and appropriate monitoring intra-operatively. Thirdly, central neuraxial blockade is fraught with risk due to haemangiomas and spinal arteriovenous malformations, tendency for coagulation disorders, and venous dilation that can cause epidural haematomas.[4] However, it must be noted that central regional blockade has been carried out safely after ruling out vascular malformations in the central nervous system with computed tomography/magnetic resonance imaging, and ensuring absence of cutaneous lesions overlying the site of needle insertion.[3]

Many patients have venous thrombophlebitis (50%) and pulmonary thromboembolism (22%) which may lead to pulmonary hypertension and right ventricular failure.[4] Arteriovenous malformations can produce high output congestive heart failure. Pre-operative cardiology evaluation must be ensured, and deep vein thrombosis prophylaxis must be considered.

If central venous pressure monitoring is planned, ultrasound guidance can help to rule out vascular malformations of the jugular/subclavian veins.[4] Femoral cannulation is better avoided in view of lower limb thrombophlebitis with venous anomalies. As the presence of brain haemangiomas pose a risk for intra-operative haemorrhage, measures must be taken to minimise surges in blood pressure.[4] With the above-mentioned precautions the anaesthesiologist can ensure a favourable outcome in KTS patients undergoing surgery.