23. Emergencies in cardiovascular surgery

Emergencies in cardiovascular surgery

Cardiovascular surgical emergencies include acute aortic syndromes, ruptured aneurysm, acute limb ischaemia, major vascular trauma, cardiac tamponade, acute valvular failure, infective endocarditis with complications and complications of cardiac surgery.
Use ABCDE assessment, continuous ECG and haemodynamic monitoring, large-bore IV access, blood sampling/crossmatch and early involvement of the relevant cardiothoracic or vascular team.
Resuscitation must be tailored: uncontrolled haemorrhage may require permissive hypotension until haemorrhage control, whereas cardiogenic shock needs careful perfusion support. Do not delay definitive intervention in unstable patients for non-essential tests.

Acute aortic syndromes include aortic dissection, intramural haematoma and penetrating atherosclerotic ulcer. Sudden severe chest/back pain, pulse deficit, neurological deficit, aortic regurgitation or shock are warning features.
CT angiography is the main investigation in stable patients; bedside echocardiography may identify proximal dissection, tamponade or severe aortic regurgitation.
Type A dissection involving the ascending aorta requires emergency cardiac surgical assessment and usually urgent repair. Type B disease is initially managed with anti-impulse therapy unless complicated by rupture, malperfusion, expansion or refractory pain/hypertension.
Ruptured abdominal aortic aneurysm may present with abdominal/back pain, hypotension and a pulsatile mass. Immediate vascular referral, blood-product resuscitation and urgent endovascular or open repair are required.

Acute limb ischaemia presents with the six Ps: pain, pallor, pulselessness, paraesthesia, paralysis and poikilothermia. Motor/sensory deficit indicates a threatened limb.
Start IV unfractionated heparin unless contraindicated, provide analgesia and urgent vascular assessment. Duplex or CT angiography is used when it does not delay treatment. Revascularisation may involve embolectomy, thrombectomy, bypass or catheter-directed therapy; fasciotomy may be required for compartment syndrome.
Vascular trauma requires direct pressure, tourniquet where appropriate for life-threatening extremity haemorrhage, resuscitation and rapid haemorrhage control. Hard signs usually mandate immediate operative/endovascular management.

Cardiac tamponade causes obstructive shock with hypotension, raised venous pressure and muffled heart sounds; echocardiography confirms pericardial effusion and haemodynamic compromise. Traumatic tamponade often requires surgical drainage rather than simple pericardiocentesis.
Acute papillary muscle rupture after myocardial infarction causes severe mitral regurgitation and pulmonary oedema; ventricular septal rupture causes a new harsh murmur and shock. Both require urgent cardiology/cardiac surgery involvement.
Prosthetic valve thrombosis, endocarditis with abscess, acute severe valve failure and postoperative bleeding are time-critical. Management depends on cause and may include anticoagulation, thrombolysis in selected circumstances, antibiotics, valve surgery or re-exploration.