Neuroendocrine and inflammatory aspects of surgery: do they affect outcome?

The cortisol stress response induced by surgery: A systematic review and meta-analysis

OBJECTIVE

Surgery is a stressor that can be categorized by duration and severity and induces a systemic stress response that includes increased adrenal cortisol production. However, the precise impact of surgical stress on the cortisol response remains to be defined.

DESIGN

We performed a systematic review and meta-analysis to assess the cortisol stress response induced by surgery and to stratify this response according to different parameters.

METHODS

We conducted a comprehensive search in several databases from 1990 to 2016. Pairs of reviewers independently selected studies, extracted data and evaluated the risk of bias. Cortisol concentrations were standardized, pooled in meta-analysis and plotted over time.

RESULTS

We included 71 studies reporting peri-operative serum cortisol measurements in 2953 patients. The cortisol response differed substantially between moderately/highly invasive and minimally invasive surgical procedures. Minimally invasive procedures did not show a peri-operative cortisol peak, whereas more invasive surgeries caused a cortisol surge that was more pronounced in older subjects, women and patients undergoing open surgery and general anaesthesia. The duration of the procedure and the use of etomidate for induction of anaesthesia did not affect the cortisol response.

CONCLUSIONS

The peri-operative cortisol stress response is dynamic and influenced by patient-specific, surgical and anaesthetic features. However, the available evidence is derived from highly heterogeneous studies, with only two of 71 studies measuring cortisol by mass spectrometry, which currently prevents a precise and reproducible definition of this response.

Comparison of the neuroendocrine and inflammatory responses after laparoscopic and abdominal hysterectomy

BACKGROUND

Laparoscopic surgery is associated with a more favorable clinical outcome than that of conventional open surgery. This might be related to the magnitude of the tissue trauma. The aim of the present study was to examine the differences of the neuroendocrine and inflammatory responses between the two surgical techniques.

METHODS

Twenty-four patients with no major medical disease were randomly assigned to undergo laparoscopic (n = 13) or abdominal hysterectomy (n = 11). Venous blood samples were collected and we measured the levels of interleukin-6 (IL-6), CRP and cortisol at the time before and after skin incision, at the end of peritoneum closure and at 1 h and 24 h after operation.

RESULTS

The laparoscopic hysterectomy group demonstrated less of an inflammatory response in terms of the serum IL-6 and CRP responses than did the abdominal hysterectomy group, and the laparoscopic hysterectomy group had a shorter hospital stay (P < 0.05). The peak serum IL-6 (P < 0.05) and CRP concentrations were significantly less increased in the laparoscopic group as compared with that of the abdominal hysterectomy group (P < 0.05), while the serum cortisol concentration showed a similar time course and changes and there were no significant difference between the groups. The response of interleukin-6 showed a significant correlation with the response of CRP (r = 0.796; P < 0.05).

CONCLUSIONS

The laparoscopic surgical procedure leaves the endocrine metabolic response largely unaltered as compared with that of open abdominal hysterectomy, but it reduces the inflammatory response as measured by the IL-6 and CRP levels.