4. Postoperative management

The goal of postoperative management is to enhance recovery and encourage patients to participate in physical rehabilitation soon after surgery. To optimize outcome and prognosis, multiple evidence-based principles of postoperative care are required.

#### 4.1. Traditional care principles

Recent studies do not recommend the routine insertion of drain, nasogastric tube, or urinary catheter after surgery, as these tubes limit the patients to their early mobilization and ambulation [35].

#### 4.2. Infectious prophylaxis

Postoperative prophylactic antibiotics are often used, but the duration was recommended no longer than 24 hours postoperatively [14].

## 4.3. Thromboprophylaxis

Antifibrinolytic agents such as tranexamic acid (TXA) decreased the rate of fibrinolysis and therefore stabilizes fibrosis clot [30]. It can be administrated by oral, intra-venous, intramuscular, or intra-articular. Current literature had shown the effect of reducing blood loss, less reduction of postoperative hemoglobin and less swelling with strong evidence [31–33]. In addition, there's no increased risk for deep vein thrombosis (DVT) among related studies.

Maintenance of intraoperative normothermia (defined as a condition of normal core body temperature around 36.5 to 37.5C) is recommended in current surgical guidelines (AHRQ, WHO, and SCIP) in order to minimize the incidence of complications. Although most surgical guidelines recommend maintaining patients in a normothermia status, the role is still controversial and unclear as these guidelines are often based on limited evidence outside the field of orthopedics. Several studies have suggested that perioperative hypothermia may increase perioperative blood loss, transfusion rate, risk of surgical site infection or the incidence of

Patients who underwent general anesthesia or experienced longer operating time were at higher risk of who developing hypothermia. However, some studies showed the contrary result. Even though hypothermia increases the amount of estimated blood loss, it did not increase transfusion rate, postoperative complications, length of hospital stay or the rate of 30-day readmission [34]. In general, it is still recommended that patients' core temperature should be constantly moni-

The goal of postoperative management is to enhance recovery and encourage patients to participate in physical rehabilitation soon after surgery. To optimize outcome and prognosis,

Recent studies do not recommend the routine insertion of drain, nasogastric tube, or urinary catheter after surgery, as these tubes limit the patients to their early mobilization and ambula-

Postoperative prophylactic antibiotics are often used, but the duration was recommended no

tored throughout the operation to maintain normothermia status.

multiple evidence-based principles of postoperative care are required.

3.5. Maintenance of normothermia

118 Primary Total Knee Arthroplasty

cardiovascular morbidities.

4. Postoperative management

4.1. Traditional care principles

4.2. Infectious prophylaxis

longer than 24 hours postoperatively [14].

tion [35].

Patients who undergo TKA are at high risk of venous thromboembolism(VTE) as the incidence of symptomatic and asymptomatic VTE is 10% and 40–60%, respectively [36, 37]. After admission, a complete assessment of VTE risk is performed. Thromboprophylaxis measures include general, mechanical and pharmacological strategies. General thromboprophylaxis including avoidance of dehydration, early mobilization and lower limb range of motion exercises are applied to patients at any risk. Mechanical thromboprophylaxis including stockings or intermittent pneumatic calf compression are used during operation. While pharmacological strategies, for instance, low molecular weight heparins should be started 6 to 12 hours after surgery [38].

#### 4.4. Pain relief

TKA is often associated with moderate to severe postoperative pain during the early postoperative period. Effective pain management following total knee arthroplasty is critical for which enables early mobilization, ambulation and even patients' satisfaction via the reduced adverse physiological and psychological responses [39, 40].

In traditional clinical practice, opiates play a major role in postoperative pain management. However, despite the strong analgesic effect of opiates, there are a number of associated adverse effects, e.g., nausea, vomiting, or risk of addiction. The associated adverse effects could further delay the recovery of the patients and increase the overall healthcare expenditure. Current literatures recommend the application of opioid sparing regimen with multimodal analgesics. It was proven to provide adequate pain control and avoidance of opioid-related adverse effects. Combination analgesics such as paracetamol, NSAIDs, COX-2 inhibitors, neuropathic medication or NMDA antagonist block different pathways of pain to optimize analgesic efficacy [41]. Combination therapy also reduces the required dose of individual medication which further lowers the incidence of medication adverse events. Other alternative modalities such as cryotherapy, through the application of cool water to the surgical site or transcutaneous electrical nerve stimulation (TENS) are also taken into consideration, as studies have shown to reduce the acute pain after surgery [42, 43].

#### 4.5. Ambulation and exercise

Early ambulation and exercise should be valued as an important part of the fast track program as it provides a range of health benefits [44]. Current literature suggests that rehabilitation and physical therapy initiated on the day of surgery. Early mobilization potentially prevents complications such as venous thromboembolism, atelectasis, urinary tract infection, stroke,…, etc., [45]. Furthermore, it was reported by related studies to reduce length of hospital stay, post-operative morbidity and mortality, improved patient satisfaction, and reduced VTE and its sequelae [45, 46].
