**3.1 Intrathecal morphine**

Intrathecal morphine has emerged as an alternative approach to managing postoperative pain following THA and TKA. Intrathecal administration of morphine would manage pain experienced by a patient with lower limb surgery and is commonly used for other procedures such as intra-abdominal and caesarean operations. However, the risks might be respiratory depression, bradycardia and hypotension, seizures, and urinary retention [32].

Both intrathecal morphine and LIA minimise the need for systemic opioid usage and improve patient outcomes. A large meta-analysis performed by Qi et al. compared intrathecal morphine to LIA in patients with THA and TKA [33]. Patients receiving LIA required less systemic opioids (13.52 mg) and had better visual analogue score at rest and mobility at 72 hours, and lower incidence of nausea or vomiting post-operatively.

#### **3.2 Epidural anaesthesia**

The epidural catheter is another option for managing pain in THA and TKA patients. Although less commonly used, it is a good way to manage pain and avoid use of oral opioids. While effective, it also carries certain risks including urinary retention, neurological deficits and epidural hematoma, and has a number of contraindications [34]. Berninger et al. in their study found that no difference in pain among different combination of anaesthesia and nerve blocks, however they found that the group that included LIA had higher mobilisation and better muscle strength in the early post-operative phase [35].

#### **3.3 Peripheral nerve block**

Peripheral nerve blocks are another widely accepted method for analgesia peri-operatively and post-operatively for THA and TKA. The blocks minimise pain experienced by the patient whilst being more specific than systemic opioids or intrathecal/epidural analgesia. Peripheral nerve blocks however can cause some delays peri-operatively compared to LIA. A sterile field, commonly with ultrasound needs to be prepared and is performed before or after operation, as compared to LIA which is performed intra-operatively.

#### *Fast Track Arthroplasty Using Local Infiltration Analgesia DOI: http://dx.doi.org/10.5772/intechopen.99433*

A large meta-analysis found that pain six hours post-operatively was better when LIA is used compared to peripheral nerve block, but there was no difference between the two for pain later, opioid consumption, length of stay and complications such as deep infection and VTE [36]. Berninger et al. found that the LIA group had better mobility than those who had peripheral nerve blocks, but other parameters were no different [35]. It can be argued that better pain relief acutely and better mobility post-operatively can reduce risk of complications, such as VTE, and would improve patient satisfaction and outcomes [35].

Two common peripheral nerve blocks used for TKA are femoral nerve block and adductor canal block. Kim et al. in their randomised trial, patients underwent TKA received either an adductor canal block or a femoral nerve block, and measured quadricep strength and pain scores at different time frames [37]. They found that the adductor canal group had better quadriceps strength in the 6-to-8-hour post-operative window compared to the patients receiving femoral nerve block, and pain was no different. Quadriceps strength and pain was no different after 24 hours post-operatively. A key fundamental to Fast Track Arthroplasty is early mobilisation and return to function; avoiding motor blockade would assist a patient to functionally progress earlier.

#### **3.4 Complementary patient-controlled analgesia (PCA)**

PCA is a commonly used pain management technique that individualises patient need for analgesia and aims to give patients control over their pain management; this helps determine the required oral analgesia. Pandazi et al. performed a randomised controlled trial; two of the included groups were LIA with PCA as rescue versus PCA alone in patients receiving THA [38]. The LIA group was shown to have significantly better pain scores at rest and when mobilising, and had less overall morphine consumption, with no difference in adverse events.

PCA combined with LIA can help manage pain post-operatively for patients with THA and TKA. For some patients however, adding another intravenous line can impede mobility – the enhanced recovery after surgery (ERAS) aims to mobilise patients as soon as possible. A multi-modal approach to analgesia should be utilised, with LIA providing a useful option in a patient's management.

#### **4. Fast track hip and knee arthroplasty is not a new idea**

The use of fast track or rapid recovery arthroplasty has been successfully implemented within multiple health systems in many different countries globally over the past 10–15 years [14, 39–43]. To successfully implement fast track arthroplasty, the care pathway involved is complex and multidisciplinary. Goals include ensuring correct indication for surgery and candidate selection, pre-operative optimisation, safe and evidence-based peri-operative management, good functional outcome and high patient satisfaction [44]. According to the Enhanced Recovery After Surgery (ERAS) Society, there are about 20 components of care involved for implementation of effective protocols, which is undertaken in a multidisciplinary fashion including expertise from anaesthetics, surgery, physical therapy, nursing and nutrition [7]. These protocol has been successfully implemented into multiple surgical specialities including gynaecological oncology, urology, vascular and thoracic surgeries [7]. Along with individual studies, systematic reviews and meta-analysis highlighted the benefits of fast-track arthroplasty for lower limb [6, 7, 9].

Malviya et al. implemented a rapid recovery protocol for hip and knee arthroplasty in May 2008 in the United Kingdom. They found the median LOS decreased from

6 days to 3 days and requirement for blood transfusion reduced from 23% to 9.8%, which was statistically significant. Most notably there was a reduction in 30-day mortality from 0.5% to 0.1% along with reduction in 90-day mortality of 0.8% to 0.2% [42].

A retrospective study conducted by Auyong et al. on 252 patients who underwent rapid recovery protocol, showed a reduced length of stay, improved mobility, reduced overall opioid consumption with no difference in readmission rates or complication rates [39].

In Australia, Christelis et al. in their study on 709 patients compared a pre-ERAS and post-ERAS cohort. They found the ERAS group had a reduced LOS with no change in complication rates by 6 weeks post operatively, no increase in hospital readmission along with similar pain scores, and higher patient satisfaction at the 6 weeks post-operative mark [40].

Same day discharge arthroplasty has emerged recently that showed cost-effectiveness without jeopardising clinical outcomes [45]. Basques et al. identified several patient characteristics which favoured same day discharge including decreased age, male, lower ASA class, less obese along with lower rates of respiratory disease and hypertension [46].

#### **5. Author's LIA technique**

LIA is an effective method of post-operative pain control in hip and knee arthroplasty [11, 14]. This, combined with low- or no-dose opioid spinal anaesthesia, allows virtually avoids urinary catheters and ensures earlier mobilisation. This multi-modal opioid-sparing approach is central to the rapid recovery model of care, allowing safe early mobilisation with minimal pain. With the use of LIA there is the advantage of having no motor blockade [8], allowing the patient to be mobilised day of surgery.

The purpose of adoption of LIA technique is to provide comfort from the trauma associated with hip and knee arthroplasty particularly for the first 36 h post-operatively, during the time of high post-operative pain, to facilitate increased post-operative mobilisation and function. Further benefits for the use of LIA include no motor blockade also enabling mobilisation, along with reducing the requirement for systemic agents including opioids with associated negative side effects like nausea, vomiting and drowsiness [8, 14]. We have not observed local anaesthetic toxicity, impaired wound healing or increased risk of infection with the use of post-operative pain catheters inserted intra-articularly [8]. Further detail on evidence surround local anaesthetic toxicity is addressed in Section 2 however, nor have other authors found increased infections in hip and knee arthroplasty [13, 19].

The use of bolus injections via 0.22um filter and wound catheter into the joint on the morning after surgery possibly extravasates into surrounding tissues, especially in hip arthroplasty. However, dispersing the injection over a larger area is probably advantageous relative to local anaesthetic infusion, which may be concentrated at the tip of the wound catheter. Furthermore, it avoids "extra baggage" for the patient to carry.

Our LIA technique augments our multimodal therapy approach. Patients routinely receive paracetamol 1 g qid, meloxicam 7.5 mg bd, for more painful operations (TKA, or posterior approach THA) buprenophine 5ug/hr. patch, and tramadol 50 mg 3/24 prn.

#### **5.1 Intra-operative considerations**

LIA administration intraoperatively there are four aspects which need consideration; the components of the drug mixture, the injection of the mixture, the catheter placement and, application of compression bandage for TKA [14]. The details of the drug mixture are discussed in Section 2. Before wound closure, a

#### *Fast Track Arthroplasty Using Local Infiltration Analgesia DOI: http://dx.doi.org/10.5772/intechopen.99433*

catheter is inserted either intra-articular or periarticular for post-operative continuous or bolus application of LIA mixture.

The commonly used catheter is a 16G Tuohy needle, an 18G epidural catheter, and a 0.22-u high-performance antibacterial flat epidural filter (Portex, Smiths Medical) [10, 14, 19]. The use of a antibacterial filter has laboratory experiments show sustained efficacy of their use for 48 h continuous infusion [47] with efficacy in antimicrobial filtration for up to 60 days with low volume and low injection pressures [48]. To date the use of antibacterial filters have been used in several applications like epidural catheters and within LIA for post-operative delivery of anaesthesia with no reported increase in infections.
