ERAS (Enhanced recovery after surgery) programs have been widely adopted in elective orthopaedic practice. Early discontinuation of Intravenous (IV) fluids in order to promote mobilisation and subsequent discharge is a key feature of such programs. However concerns have been raised regarding whether such an approach results in an increased risk of acute kidney injury (AKI).

We set out to determine the incidence of AKI in patients undergoing hip or knee arthroplasty treated as part of an ERAS program where IV fluids are removed before leaving the recovery room. Investigate whether there is a difference in incidence between patients with a pre-operative eGFR ≥ 60 or < 60 (ml/min/1.73m2). In addition to whether patients who sustain an AKI have a longer post-operative hospital stay.

The pre and post-operative blood results of patients undergoing elective total hip and total knee replacements were retrospectively analysed to determine whether they had suffered an AKI during admission. The patient's notes were reviewed for other known causes of peri-operative AKI and the length of their hospital stay.

The overall Incidence of AKI was 9.4%. There was a significant association found between pre-operative eGFR and development of an AKI p = 0.002. The incidence of AKI was 5.8% in patients with a pre-operative eGFR ≥ 60 vs 33.3% in those with an eGFR < 60. The development of an AKI was associated with a longer hospital stay p = 0.042. The median length of hospital stay was 7 days for those who suffered an AKI vs 5 days for those who did not.

Patients undergoing elective lower limb arthroplasty with a pre-operative eGFR < 60 treated as part of an ERAS program where fluids are discontinued before leaving the recovery room are at high risk of developing an AKI. Further studies are required to ascertain whether a longer duration of IV fluids is effective in reducing the incidence of AKI in this group.

Intro

Distal radial fractures are a commonly encountered fracture & anatomical reduction is the standard. Dorsal angulation is the traditional method of assessment but is inaccurate in rotated lateral xrays. Previously a relationship has been demonstrated between the dorsal cortex (DC) of the radius & the superior pole of the lunate (SL) & its sensitivity for assessing dorsal angulation & translation.

Magnetic resonance imaging (MRI) validation of a novel method of assessing Distal Radial Fracture (DRF) reduction using the hypothesised constant relationship between the dorsal radial cortex (DC) and the superior pole of the lunate (SL).

MRI scans of 28 normal wrists were examined. Scans included the distal third of the radius to the proximal carpal row. Beginning 5cm proximal to the distal radius articular surface, a line was superimposed upon the DC extending distally through the metaphyseal flare.

Lunate height (LH) and distance from the DC line to the SL (DC-SL) were measured at 5-degree rotational increments around the radial shaft central axis to a total of 30 degrees of supination and pronation (S+P). The DC-SL/LH ratio was compared to 0 degrees (anatomical lateral) using the two-tailed paired student t-test.

There was no significant difference in DC-SL:LH between 0 degrees of rotation and any 5-degree increment up to 30 degrees of S+P (lowest p=0.075). The DC line lay consistently dorsal to the SL.

A constant DC-SL relationship exists with up to 30 degrees of S+P. This reference can be quickly and accurately used to assess DRF reduction in poorly-taken films with malrotation up to 30 degrees from anatomical lateral. Research comparing DC-SL distance with volar tilt to assess DRF reduction is needed.