Perioperative care Flashcards
Cardiopulmonary exercise test indications
Preop evaluation for lung resection or lung volume reduction surgery, evaluation for lung or heart transplant, exercise plan for pulmonary rehabilitation, evaluation or impairments.
Surgical thrombosis risk factors-
Cancer, 60+, dehydration, thrombophilia, BMI 30+, comorbidities, personal or familial VTE history, use of HRT, combined oral contraceptive, varicose veins with phlebitis, pregnancy or less than 6 weeks postpartum, immobility, lower limb joint replacements/fracture, 90mins+ procedure, inflammation and critical care admission.
Surgical bleeding risk factors-
Active bleed, acquired bleeding disorder eg liver failure, warfarin/anticoagulants, acute stroke, thrombocytes <75x10 9/L, 230/120mmhg or more, untreated haemophilia ,neuro/spine/eyes surgery, peripheral block or regional.
Multiple organ dysfunction syndrome
Systemic inflammatory organ response, includes sepsis, major trauma, burns, pancreatitis, aspiration syndrome, extracorporeal circulation, multiple blood transfusion, ischemia-reperfusion injury, autoimmune disease, heart related, eclampsia, poisoning/toxicity.
Symptoms- altered mental state, dec urine output, respiratory deterioration, dec cardiac function, deranged metabolic status, fluid imbalance, clammy/pale, faint pedal pulses, dec cardiac output: dec bp and arrhythmias may occur.
Signs of surgical emphysema
Gas in soft tissues from trauma or tracheobronchial perfusion. Can get sore throat, neck pain, swelling of chest and neck, impaired breathing and speaking, wheezing. Looks like diffuse crackly opacity even outside lung field or crack lines on CXR.
Lipodermatosclerosis
Inflammation and fibrosis under the skin and fat from venous insufficiency. Pain, hardening of skin, redness/dusky, swelling, tapering of legs above ankles.
Results from incompetent venous valves, venous outflow obstruction, heart valve issues. More common in middle-old age, female, immobile, obese.
Acute phase- can mimic cellulitis w/ induration (hardening), erythema, pain, itch, ache, swelling and heavy legs.
Chronic phase continues symptoms with subcutaneous fibrosis that narrows the lower leg to look like an upside down champagne bottle. Might also have hyperpigmentation, white atrophy scars, varicose veins, venous eczema, ulcers.
Differentials- erythema nodosum, morphea, cutaneous vasculitis, necrobiosis lipoidica.
Stanozolol reduces dermal thickness, pentoxifyline helps instead of compression for the ulcers if not tolerable.
Causes of post-operative breathlessness
Basal atelectasis (also common in smokers). pneumonia, PE, resp failure via opiates, metabolic acidosis (renal failure or sepsis), MI, fluid overload, ARDs, phrenic nerve damage, fat embolism after a fracture, anemia, myasthenia gravis, COPD, UIP.
Rheumatic fever
Systemic inflammatory disorder complicating from strep A (pyogenes). Can be prevalent in indigenous groups. RF = one of the biggest causes of paediatric cardiac disease.
Affects children between 5-15. Rf can return later in life if untreated. Typically shows 1-5 weeks after a strep throat pharyngitis or skin infection. A type two hypersensitivity response. Inflammation attacks the heart valves (mitral commonly or aortic) due to antigen mimicry.
Clinical features = Jones criteria - pos throat swab culture, rapid antigen test, ASo or DNAse Btitres (inc antibodies) or recent scarlet fever. Must have one of these with either a major and minor symptom or two majors.
Majors- Hot, red flitting polyarthritis, carditis, sydenham’s chorea movements as late sign, erythema marginatum like graffiti red marks- macular and spreads outwards on trunk and limbs, subcutaneous extensor nodules if carditis severe.
Minors- polyarthralgia, inc p-r, raised crp, esr or wbcs.
Give single benzylpen iv, then 10 days penicillin V. If allergic- 10 days erythromycin or azithromycin.
Follow-up is IM benzathine penicillin G per 4 weeks. If no heart issues- give for 5 years or to 21. If carditis- 10 years, if valve disease- until 40 years old.
Mitral reg is most common lesion, mitral stenosis is most common long term valve effect.
Arterial ulcers
An arterial ulcer refers to an ulcer caused by a reduction in arterial blood flow, leading to decreased perfusion of the tissues and subsequent poor healing.
They often form as small deep lesions with well-defined borders and a necrotic base. They most commonly occur distally at sites of trauma and in pressure areas (e.g the heel).
The main risk factors are those of peripheral arterial disease, including smoking, diabetes mellitus, hypertension, hyperlipidaemia, increasing age, positive family history, and obesity and physical inactivity.
Intermittent claudication on walking, critical limb ischemia/pain at night, pain without gravity to perfuse, eg elevated leg- helps to dangle. For same reason that muscle atrophies in the limb with poor supply.
Develops over long time. Can have cold limbs, thickened nails, necrotic toes, hair loss.
Neuropathic ulcers
Neuropathic ulcers are painless ulcers over areas of abnormal pressure, often secondary to joint deformity in diabetics who could not feel an area which leads to repetitive stress and unnoticed injuries forming.
Neuropathic ulcers can develop with any condition with peripheral neuropathy, the most common being diabetes mellitus and B12 deficiency.
Ulcer risk is further compounded by any foot deformity or concurrent peripheral vascular disease.
Punched out appearance. Can get pain and tingling in the limb with neuro issues, mononeuritis multiplex or painful wasting of proximal quadraceps= amotrophic neuropathy.
Venous ulcers
Venous ulcers are shallow ulcers with a granulated base, often with other clinical features of venous insufficiency present. Typically appear over medial malleolus. Venous obstruction leads to impaired venous return , traps wbcs in capillaries and forms fibrin cuff around the vessel hindering O2 transport to the tissue, leads to tissue injury, poor healing and necrosis.
Risk factors- age, VTE or venous incompetence, varicose veins, pregnancy, obesity, inactivity, leg ingury.
Might have oedema, varicose eczema, thrombophlebitis, haemosiderin skin staining, lipodermatosclerosis.
An Ankle Brachial Pressure Index (ABPI) is required to assess for any arterial component to the ulcers and to determine whether compression therapy will be suitable.
Duplex Ultrasound shows most commonly venous incompetence occurs at the sapheno-femoral or sapheno-popliteal junctions.
Charcot’s foot
Charcot’s foot is neuroarthropathy with loss of joint sensation results in continual unnoticed trauma and deformity occurring. The deformity predisposes the patient to neuropathic ulcer formation.
Patients present with swelling, distortion, pain (typically less than may be expected with such a deformity), and loss of function. Any deformity causing the loss of the transverse arch is termed a “rocker-bottom” sole.
Warfarin issues/specific situations with general anaesthetic
Mechanical valves trigger clotting cascade with ejection so can’t take off warfarin for surgery. If other situation on warfarin but anticoagulation is essential, can give a heparin infusion 4hr before surgery. Beta blockers should always be continued during surgery, statins too. ACE stopped on the morning.
Dupuytren’s contracture
Fingers permanently flexed with hard nodule just under skin. Gradual onset males 50+.
Risk factors- fx, alcoholism, smoking, thyroid problems, liver disease, diabetes, epilepsy. Give steroid injections or inject clostridial collagenase.
Transverse abdominal pain block
Peripheral nerve block designed to anesthetise nerves of the anterior wall from T6-L1. Placed midaxillary line between costal margin and iliac crest.
