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Tebala et al. Mini-invasive Surg 2018;2:32 I http://dx.doi.org/10.20517/2574-1225.2018.37 Page 7 of 18
at least in elective patients with no important comorbidities. Obviously, cardiac output remains the best
indicator of volaemia (and oxygen delivery), but pulse, blood pressure and urine output are generally con-
sidered good enough to guide fluid infusion in rectal surgery. The growing diffusion of laparoscopic sur-
gery, which entails reduced evaporative fluid loss and reduced blood loss with respect to open surgery, has
helped significantly to reduce the amount of volume to be infused. However, the recent RELIEF trial failed
to demonstrate a higher rate of disability-free survival and pointed out an increased risk of acute renal
[55]
failure in patients with restricted fluid infusion . Although this interesting study is gradually contribut-
ing to switching the paradigm of restrictive fluid infusion, we can reasonably admit that at the moment the
pathophysiology of fluid infusion during surgery is not yet completely understood and we may still decide
case by case on empiric bases until more definitive evidence becomes available.
The vast majority of published articles do not differentiate between colonic and rectal surgery, but rectal
surgery is more easily associated with dehydration or hypovolaemia due to increased duration of surgery,
bowel preparation and possible blood loss in the pelvis, therefore a less restrictive fluid infusion may be ad-
visable.
Our attitude is to reasonably limit the intraoperative infusion to maintain adequate tissue perfusion dur-
ing the operation and to allow the patient to consume free or clear fluids as soon as he or she is awake and
comfortable in the recovery room after surgery. Invasive monitoring of the cardiac dynamics increases
the risks, delays the mobilization and raises the costs of surgery, but it may be necessary in selected cases,
mostly in unprepared patients.
Antibiotic prophylaxis and DVT prophylaxis
It has been widely demonstrated that systemic antibiotic prophylaxis reduces the risk of postoperative
[56]
infections . Both ultra-short term prophylaxis (a single dose before surgery) and short term prophylaxis
(a preoperative dose plus 24 h coverage after surgery) revealed effective. It is still a matter for debate what
antibiotics should be used. Clearly, they must be active on aerobic and anaerobic so usually a combination
of two antibiotics is needed, but the choice is usually left with local policies and protocols. The first dose
should be administered within 1 h from skin incision. Apparently, the association of intravenous and oral
[57]
antibiotic is more effective than intravenous alone . Much debate has been done recently on the use of in-
traluminal antibiotics in association with mechanical bowel preparation (see dedicated paragraph), which
would be able to reduce the risk of ileus and leak.
DVT prophylaxis has been one of the pivots of the traditional perioperative management for decades. It is
well known that the correct administration of low-molecular-weight heparin and the use of thromboem-
bolism deterrent stockings (TEDS) would decrease the risk of DVT and pulmonary embolism. Obviously,
this best practice has been integrated into the ERAS protocols.
Anaesthesia
Open rectal surgery usually needs a long abdominal incision, a wide pelvic dissection and sometimes also
a perineal incision with severe disruption of the pelvic floor. The laparoscopic approach reduces the trauma
of the midline laparotomy, even if often a small laparotomy may still be needed, but increases the operative
time and adds the further pathophysiologic trauma of a steep Trendelenburg position.
The ERAS principles pertaining to anaesthesia are: (1) short-acting agents to expedite the postoperative
recovery; and (2) optimal pain control with minimal use of opioids. Intraoperative pain relief can be ob-
tained with a blended approach with epidural analgesia (see postoperative analgesia) and short acting opi-
oids. Remifentanyl can reduce the surgical trauma and the stress response. Muscle relaxation is essential in