Abstract
Introduction Laparoscopic colorectal surgery and enhanced recovery programs have been shown to improve patient outcomes and reduce length of stay following surgery. The use of regional analgesia is usually a fundamental element of an enhanced recovery program. A proposed benefit of regional analgesia in colorectal surgery is suppression of the post-operative stress response. No data is available to indicate if this is applicable in laparoscopic colorectal surgery. In addition there is no direct evidence addressing whether there is an appropriate type of fluid, crystalloid or colloid, to use in goal-directed fluid therapy. The aim of this study was to examine the effects the choice of analgesia and intravenous fluid had on physiological and biochemical outcomes following laparoscopic colorectal surgery in patients within an enhanced recovery program. Methods A randomized clinical trial (NCT 01128088) was conducted between 2010-2011 at a single institution. All patients underwent laparoscopic colorectal surgery for benign or malignant conditions within an established enhanced recovery program. Patients were randomly assigned to receive either a spinal or morphine PCA as their primary post-operative analgesia. In addition, patients were randomly allocated to receive either 6% Volulyte or Hartmann’s solution, which was administered as directed by an oesophageal Doppler monitor in order to achieve stroke volume optimisation. Blood was taken to measure aspects of the stress response at pre-op, 3, 6, 12, 24 and 48 hour time intervals. Various other physiological and patient outcomes were measured. Results One hundred and twenty patients were analysed in the study. There was no significant difference in patient characteristics between the groups. No significant difference was seen between the analgesia groups at pre-op, 3, 6, 12, 24 or 48 hours in the levels of insulin, IL-2, 4, 6, 8, 10, 12, TNF-α, VEGF or IFN-γ. Median cortisol (468 nmol/l (IQR: 329-678) vs 701 nmol/l (IQR: 429-820); p=0.004) and glucose (6.1 mmol/l (IQR: 5.4-7.5) vs 7 mmol/l (IQR: 6-7.7); p=0.012) levels were significantly lower at 3 hours post-op in the spinal group and thereafter the same. Patients receiving Hartmann’s solution received significantly greater volumes of fluid in comparison to those receiving 6% Volulyte (20.98ml/kg (IQR: 16.68-25.73) vs 13.95ml/kg (IQR: 11.76-18.1); p<0.0005). There was no significant difference in the median length of stay between either fluid (6% Volulyte 2.75 days [IQR: 2.08-3.6] vs Hartmann’s 2.29 days [IQR: 2.01-3.59]; p=0.807) or analgesia (spinal 2.25 days [IQR: 1.89-3.13] vs PCA 2.9 days [IQR: 2.09-3.93]; p=0.059) groups. The number of complications was no different between the two types of fluids but patients receiving spinal analgesia (20% vs 37%, p=0.013) had a significantly reduced number. Conclusion Following laparoscopic colorectal surgery within an enhanced recovery program the use of spinal analgesia in comparison to morphine PCA significantly reduces the levels of cortisol and glucose at 3 hours only. This difference does not translate to a reduction in length of stay. There is no effect on other aspects of the stress response at various post-operative time intervals. A significantly greater quantity of Hartmann’s solution is required to achieve stroke volume optimisation in comparison to 6% Volulyte. This, however, did not make any difference to the incidence of post-operative complications or length of stay. Either fluid is acceptable in the quantities given in this study.