This document provides details on total hip and knee replacement surgeries. It discusses the typical patient demographics, common conditions necessitating joint replacement, and preoperative assessment of cardiopulmonary, renal, and musculoskeletal systems. Intraoperative management is outlined, including surgical approaches, positioning considerations, techniques to reduce blood loss such as hypotensive anesthesia and tourniquet use, and potential problems like hypothermia, blood loss, and cement implantation syndrome reactions. Regional anesthesia is typically preferred to provide better pain control and reduce complications.

1. PARTICULARS OF TOTAL HIP
REPLACEMENT AND TOTAL KNEE
REPLACEMENT SURGERIES.

2. INTRODUCTION
• Joint replacement – common, effective procedure for relief of
disability due to severe joint pain and loss of function, most common joints
replaced are the hip, knee and shoulder.
• Most patients for joint replacement have generalized degenerative
joint disease (eg.OA).
• Other conditions necessitating joint replacement surgery include:
› rheumatoid arthritis
› osteoporosis and fracture
› metastatic lesions and pathological fractures
› avascular necrosis of the femoral head.
• Most patients are elderly, with associated problems such as HTN,
IHD, COPD or renal disease.
• Younger pts presenting for joint replacement surgery often suffer from
rheumatoid arthritis, severe osteoporosis or obesity.

3. Preoperative assessment
Problems in multiple systems are common because
most patients are elderly.
There are specific types of pts who are more likely
to have orthopedic surgery and are more likely to
have perioperative complications.
› geriatric pts
› rheumatoid arthritis pts
› ankylosing spondylitis pts

4. Assessment of co-morbidities
Cardiopulmonary reserve
• Estimated by assessment of exercise tolerance.
such as stress tests
• The following is also used:
1. PFTs, ABG, SPO2
2. resting ECG (silent ischaemia / previous MI)
3. 2DEcho (LV function, WMA and valvular abnormality)
• Dobutamine stress tests provide information about cardiac
function under stress but they are not readily available.

5. Renal function
Renal fuction tests to be done.
And may be impaired owing to age, HTN or chronic use
of NSAIDs.
Musculoskeletal
• other joint involvement is common.
• range of limb and neck movements should be
noted.
• Obesity may be a cause or consequence of
degenerative joint disease.
• Assessment for positioning on table and for regional
blockade should be made.

6. Preoperative preparation
• Preop assessment should be carried out .
• Optimization of co-morbidities is required.
• Cross-matched blood must be available.
• DVT prophylaxis is required. If a regional technique is
Planned- pneumatic compression stockings, DVT Pumps ,if
required ensure appropriate timing of low-molecular weight
heparin.
• Antibiotic prophylaxis (usually cephalosporin or
aminoglycoside) is required.
• Invasive monitoring is seldom indicated unless there is
significant
cardiac disease or large blood loss is anticipated.
• Large bore IV access is required (non-dependent arm for
laterally positioned patients).

7. • Thromboprophylaxis in Orthopedic
Surgery
1 of leading causes of morbidity after ortho surgery.
THR, TKR, hip and pelvic fracture surgery –Have highest
incidence of DVT and Pulmonary Embolism.
Pts with symptomatic PE have 18-fold higher risk of
death than pts with DVT alone.
short-term complications of survivors of acute DVT
and PE - prolonged hospitalization, bleeding
complications related to DVT and PE treatments,
local extension of DVT, and further embolization.
Long-term complications include post-thrombotic
syndrome, pulmonary hypertension, and recurrent
DVT.

8. As venous thrombi consist of fibrin polymers, anticoagulants
administered for the prevention and treatment of DVT.
Thrombolytics should be administered only in event of a
severe, possibly fatal PE.
LMWH is recommended over unfractionated heparin (IV/SC)
for initial therapy of DVT and PE.
LMWHs do not require monitoring of coagulation.
Although DVT prophylaxis may be more efficient when
started preoperatively, the risk of surgical bleeding also
increases.
LMWH should be continued for at least 10 days in routine
orthopedic procedures & in patients not considered high risk.
Extended prophylaxis to 28 to 35 days would be supported in
patients with evidence of a DVT or at higher risk for DVT.

9. Risk factors for development of PE after surgery
1. advanced age
2. Obesity
3. previous PE and DVT
4. Cancer
5. prolonged bed rest
Warfarin - long-term treatment of DVT, with a target
INR of 2.5 maintained for the duration of therapy.
alternative to LMWH is fondaparinux, synthetic
pentasaccharide (selective inhibitor of factor Xa)

10. Intraoperative Management
THR/TKR –
APPROACHES
• anterior / lateral approach.
• anterior approach - advantage of exposure without
violation of the muscles, but restricts full access to the
femur with the risk of lateral femoral cutaneous nerve
injury.
• lateral posterior approach - excellent exposure to the
femur and the acetabulum with minimal muscle
damage, but increases the risk of posterior dislocation.
• Most surgeons prefer lateral posterior approach,
placing the patient in lateral decubitus position, surgical
side up, for operation.

11. POSITIONING
• Since Most surgeons prefer lateral posterior approach,
placing the patient in lateral decubitus position
• Anesthesiologist must be aware that this position may
compromise oxygenation, especially in obese and severely arthritic
pts, owing to V/Q mismatch.
• To prevent excessive pressure on the axillary artery and
brachial plexus by the dependent shoulder, an anterior roll or
pad must be placed beneath the upper thorax.
• Care of old and fraile pts with multiple joint Osteo. Arthritis.
TECHNIQUE
• nerve supply to hip and knee joint includes obturator, inferior gluteal, superior
gluteal, sciatic and fibular nerves respectively – hence Regional Anaesthesia best
achieved with SubArachnoid Block or epidural anesth.
• lumbar paravertebral block may be used for postop analgesia when postop
anticoagulation requires removal of epidural catheter.

12. BLOOD LOSS
• can be significant.
• Several studies have shown controlled hypotensive epidural
anesthesia with MAP of 60 mm Hg can reduce intraop blood
loss for primary THRs to approx 200 mL.
• Elderly patients able to tolerate this degree of blood pressure
reduction without cognitive, cardiac, or renal complications.
• hypotensive anesthesia may improve the cement prosthesis
to bone fixation by limiting bleeding in the femoral canal.
• femoral prosthesis can be fixed to femoral canal through
methyl methacrylate cement or bony ingrowth.
• Cemented fixation of the femoral prosthesis has been
complicated by “bone-cement implantation syndrome,”
which may result in intraop hypotension, hypoxia, and
cardiac arrest and FES postoperatively

13. TOURNIQUET APPLICATION
routinely inflated over thigh during TKA to reduce intraop
blood loss, provide a “bloodless” field for cement fixation of
femoral and tibial components.
when deflated, blood loss usually continues for next 24 hours.
Tourniquets are usually inflated to a pressure 100 mm Hg
above pt's SBP for 1 to 3 hours.
Nerve injury after extended tourniquet inflation (>120mm Hg for 1- 4 hours
has been attributed to combined effects of
ischemia and mechanical trauma.
5 min of intermittent perfusion between 1- and 2-hour
Inflations should be done , Prolonged inflation / simultaneous release of 2
tourniquets -
Can cause significant acidosis, particularly in patients with an underlying
acidosis due to other causes eg.DM.

14. Peroneal nerve palsy, a recognized complication of TKR
caused by combination of tourniquet ischemia and surgical
traction.
When prolonged tourniquet inflations are required, deflating
the tourniquet for 30 minutes of reperfusion may reduce
neural ischemia.
After tourniquet release, MAP falls significantly, partly owing
to release of metabolites from ischemic limb into circulation
& decrease in PVR.

15. Anaesthetic technique
General anaesthesia:
if general anaesthesia is indicated, bleeding may be
reduced by modest hypotension in carefully selected
patients, using volatile agents.
For hip arthroplasty, analgesia may be supplemented by
the use of a 3-in-1 (femoral/obturator/lateral cutaneous of
thigh) block.
Some anaesthetists favour a lumbar plexus block because
this also blocks the sciatic nerve, which has a component
supplying the hip.
For knee replacement, a 3-in-1 block combined with a
sciatic nerve block can be effective.

16. Regional anaesthesia
is technique of choice because it:
• reduce incidence of major periop complications with certain
surgical procedures, including DVT, PE, blood loss, respiratory
complications.
• superior pain relief.
• Peripheral nerve blocks employing long-acting anesthetics or
catheters may provide excellent intraop anesthesia and
superior postop analgesia.
• preemptive analgesia.
• manipulation of airway, & conscious patients can aid safest
& most comfortable positioning for surgery.
• suggested that epidural anesthesia reduces venous pressure,
& this is significant factor in determining surgical bleeding,
decreased need for bank blood and associated transfusion
risks.

17. Intraoperative problems
Patient position:
in the lateral position, there is a risk of excessive lateral
neck flexion and pressure on the dependent limbs.
Hypothermia:
orthopaedic theatres colder than other theatres, with a
higher velocity airflow leading to more rapid patient
cooling.
Hypothermia causes poor wound healing, infection,
coagulopathy and CVS dysfunction.
Fluid warmers, blankets and patient hats should be used
routinely.

18. Blood loss:
average blood loss in THR ranges from 300-1500 ml and may
double in the first 24 hours postop.
During TKR with an intraoperative tourniquet, most blood loss
occurs in the recovery area.
Careful fluid balance is essential because compensation for
hypovolaemia is poor in the elderly.
Cement reactions:
At the time of cementing, a drop in blood pressure and
oxygen saturation is often seen.
originally thought to be caused by a directly toxic effect of
the methyl methacrylate monomer component of the
cement, but now known to be caused by a shower of
microemboli of blood, fat or platelets forced into circulation
by high intramedullary pressure during cement packing and
prosthesis insertion.

19. microemboli are toxic to the lung parenchyma, causing
haemorrhage, alveolar collapse and hypoxia.
may be severe enough to cause cardiovascular collapse,
cardiac arrest and death.
Reactions are more common and more severe in bilateral
joint replacements
therefore vital to ensure that the patient is not hypovolaemic
before cementing.
Fat Embolism Syndrome
• well-known complication of instrumentation of medullary canal.
• physiologic response to fat within systemic circulation.
• clinical manifestations of FES include respiratory, neurologic, hematologic, and
cutaneous signs and symptoms.
• presentation of FES can be gradual, developing over 12 to 72 hours, or
fulminant leading to ARDS and cardiac arrest.

20. petechial rash is pathognomonic, usually present on conjunctiva, oral mucosa, and skin folds
of the neck and axillae.
mild hypoxemia and radiologic evidence of bilateral alveolar infiltrates, <10% progress to
ARDS.
Neurologic manifestations – drowsiness, confusion, obtundation and coma.
treatment of FES is supportive with early resuscitation and stabilization to minimize the
stress
response to hypoxemia, hypotension, and diminished end-organ perfusion.
Deep Venous Thrombosis and Pulmonary Embolus
A major cause of death after surgery or trauma to the lower extremities, incidence of fatal PE
highest in THR for hip fracture.
Effective thromboprophylaxis requires knowledge of clinical risk factors in individual patients,
such as advanced age, prolonged immobility or bed rest, prior history of thromboembolism,
cancer, preexisting hypercoagulable state, and major surgery.

21. Postoperative Complications
Cardiac Complications
• orthopedic surgery - intermediate-risk
• Older pts have an increased risk of periop myocardial morbidity and mortality after
orthopedic surgery possible reasons for this increased risk are as follows:
multiple medical comorbid conditions .
limited functional capacity.
some ortho procedures initiate a systemic inflammatory response syndrome.
significant blood loss and fluid shifts.
• All of these factors - stress response, tachycardia, hypertension, increased oxygen
demand, and myocardial ischemia. Increase cardiac morbidity.
• In pts in whom percutaneous coronary intervention involved placement of stents -
added risks of restenosis and thrombosis if antiplatelet therapy discontinued before
surgery and alternatively increased periop bleeding if not discontinued.
• In elderly pts, β-blockers should be continued periop with a target heart rate less than
80 beats/min.

22. Respiratory Complications
• elderly patients -have progressive decrease in arterial oxygen tension, an increase in
closing volumes, decrease of approx 10% in FEV1 with each decade of life.
• Due to alterations in chest wall mechanics, exacerbated in arthritis.

23. Neurologic Complications
• confusion or delirium 3rd most common complication seen in elderly patients
• associated with an increased length of hospital stay, poor functional recovery,
progression to dementia, and increased mortality.
• Postop delirium manifests as
› attention and awareness deficits
› including acute confusion
› reduced ability to focus
› change in cognition
› irritability
› anxiety
› paranoia
› hallucinations.

24. major risk factors for postoperative delirium
› advanced age
› alcohol use
› preoperative dementia or cognitive impairment
› psychotropic medications
› multiple medical comorbid conditions.
› Perioperative events (hypoxemia, hypotension, hypervolemia, abnormal electrolytes,
infection, sleep deprivation, pain, and administration of BZDs and anticholinergic
medications).

25. Postoperative management
Analgesia
Epidural analgesia
excellent, particularly in reducing quadriceps muscle spasm
following TKRs.
But has increased risk of urinary retention
And catheterisation may cause a bacteraemia, increasing the risk of prosthesis infection.
Patient-controlled analgesia is the choice in many institu-tions.
Intramuscular opiates may also be considered.
Regular paracetamol, 1 g/6 hours, should be given orally or
rectally.

26. NSAIDs used with caution, especially in elderly, owing to
increased risk of renal impairment.
Midazolam infusions or baclofen are sometimes required to ease
quadriceps muscle spasm.
Fluid balance:
stringent fluid balance monitoring is mandatory because blood
loss may double in the first 24 hours. Nausea may reduce the
patient’s oral intake.
Oxygen: perioperative ischaemia is common and generally
silent. Oxygen should be given for the first 72 hours
postoperatively.

27. In Conclusion -
The most common complications after total
hip arthroplasty and total knee arthroplasty
are cardiac events, pulmonary embolism,
pneumonia and respiratory failure, and
infections.
Older patients with major comorbidities
including cardiac disease, pulmonary disease,
and diabetes should have a complete
preoperative medical evaluation.
Comprehensive preoperative geriatric
assessment is increasingly used in the
perioperative care of older patients who may
have multiple comorbid conditions