The impact of hospital length of stay
Understanding the relationship between anaemia and surgical outcomes is
a complex model to comprehend with the multiple covariates that come
associated with low haemoglobin levels. For example, Table 2 shows the
increase incidence of anaemia with increasing age (P < 0.001),
but it is possible that increasing age alone could bring its own
challenges when considering co-morbidities (such as coronary artery
disease), frailty and social circumstances. Consequently, when
interpreting the results, it is perhaps fair to suggest that the
relationships be considered more as an additive contribution rather than
a stand-alone single causative characteristic[8].
Considering the LOS in this study, the evidence concludes that
non-anaemic patients had a statistically significant reduced hospital
length of stay than the anaemic patients undergoing major lower limb
surgery (primary hip and knee replacements). Studies have shown that an
enhanced recovery programme (ERP) can reduce length of stay[20,21],
and many hospitals within the UK now deploy an enhanced recovery
programme which include a multidisciplinary approach to the patient’s
overall care. This includes pre-operative assessment to optimise
patients medically, looking at anaesthetic techniques to reduce
post-operative pain, early mobilisation with the aid of
physiotherapists, and surgical techniques. This study focuses on the
pre-optimisation of anaemia, just one significant aspect of the ERP
given the population that present with anaemia in this cohort.
However, as stated previously, this particular characteristic cannot be
taken in isolation, and must be considered as an additive variable.
Studies have shown that anaesthetic technique for lower limb joint
replacements can alter the patient experience and the surgical outcomes
as well[21]. For example, the use of general anaesthesia has shown
to increase the requirements of post-operative opiate use for
analgesia[22], which can lead to an increase incidence of
post-operative nausea and vomiting as well as a reluctance and
difficulty in early mobilisation due to pain – both of which can
increase hospital length of stay[23]. In this study, we did not
examine the type of anaesthesia used in all patients, the type of opiate
used intrathecally for regional techniques (short acting fentanyl vs
longer acting diamorphine) and the dose it was used in, and nor did we
evaluate the concomitant use of non-steroidal anti-inflammatory drugs
(NSAIDs) which may often be omitted in patients whose conditions may
contraindicate its use. Likewise, taking into consideration surgical
techniques, we did not review the use of local anaesthetic infiltration
into the surgical site as recommended by the Hillingdon and Mount Vernon
rapid recovery programme anaesthesia and analgesia guideline published
in 2014 (Figure 2).
Figure 2: