Effect of Stellate Ganglion Block on Arterial Catheterization Complications in Selected Group of Patients Undergoing Elective Cardiac Surgeries

Invasive blood monitoring is an essential prerequisite in all cardiac surgeries where the radial artery is the most common one used. It is easily accessible, apart from important nerves and has a well-known safe profile.

As perfection is an unattainable dream, radial artery complications do happen ranging from spasm, occlusion, hematoma formation and dissection Although incidence of ischemia post radial artery occlusion is not as common as the occlusion, serious effects do happen as reported digital necrosis and the need to do below elbow amputation in one case Patients undergoing cardiac surgeries usually suffers from many risk factors for Ischemic complications as risk of hypotension and use of vasoconstrictors The use of vasoconstrictors is more expected in patients with preoperative decreased Left Ventricle (LV) function (≤30%), moderate to severe Pulmonary Hypertension (PH), multiple procedures and prolonged bypass time.

Also, a complication that is relatively common in open heart surgeries is the central to radial artery pressure gradient that is usually encountered post bypass and may last for some time after and may affect up to 45% of patients in cardiac surgeries.

Usually the pressure gradient is for favor of the radial artery in awake patients due to the vascular resistance, but many theories tried to explain the cause of the opposed gradient post bypass. One theory related the issue to Vasoconstriction of the brachial artery.

Over the last few years, there were some studies, which investigated the effect of regional anesthesia techniques such as thoracic epidural anesthesia (TEA) and stellate ganglion block (SGB) for sympatholysis in cardiac surgeries The SGB with local anesthetics have been widely used to provide pain relief to treat vascular spastic disorders of upper limbs, chronic pain conditions and treatment of refractory angina The SGB has also been used for increasing radial artery (RA) blood flow and preventing RA spasm by sympathetic blockade in coronary artery bypass surgery In the current study, SGB will be studied regarding its effect in minimizing the occurrence of complications related to arterial catheterization in selected patients in cardiac surgeries.

Inclusion criteria

• • Multiple procedures with expected prolonged bypass time (>100 min)

• EF< 35%
• Moderate or severe Pulmonary hypertension

Exclusion criteria

• • Patient not willing to participate in the study.

• History of strokes / Transient ischaemic attacks
• History of Glaucoma.
• History of allergy to local anaesthetic drugs.
• Pre-existing contralateral phrenic nerve palsy.
• Patients with existing coagulopathy.
• BMI >35