Operative blood loss adversely affects short and long-term outcomes after colorectal cancer surgery: results of a systematic review and meta-analysis.

BACKGROUND: The aim of this meta-analysis was to assess the impact of operative blood loss on short and long-term outcomes following colorectal cancer surgery. METHODS: A systematic literature review and meta-analysis were performed, from inception to the 10th of August 2020. A comprehensive literature search was performed on the 10th of August 2020 of PubMed MEDLINE, Embase, Science Citation Index Expanded, and Cochrane Central Register of Controlled Trials. Only studies reporting on operative blood loss and postoperative short term or long-term outcomes in colorectal cancer surgery were considered for inclusion. RESULTS: Forty-three studies were included, reporting on 59,813 patients. Increased operative blood loss was associated with higher morbidity, for blood loss greater than 150-350 ml (odds ratio [OR] 2.09, p < 0.001) and > 500 ml (OR 2.29, p = 0.007). Anastomotic leak occurred more frequently for blood loss above a range of 50-100 ml (OR 1.14, p = 0.007), 250-300 ml (OR 2.06, p < 0.001), and 400-500 ml (OR 3.15, p < 0.001). Postoperative ileus rate was higher for blood loss > 100-200 ml (OR 1.90, p = 0.02). Surgical site infections were more frequent above 200-500 ml (OR 1.96, p = 0.04). Hospital stay was increased for blood loss > 150-200 ml (OR 1.63, p = 0.04). Operative blood loss was significantly higher in patients that suffered morbidity (mean difference [MD] 133.16 ml, p < 0.001) or anastomotic leak (MD 69.56 ml, p = 0.02). In the long term, increased operative blood loss was associated with worse overall survival above a range of 200-500 ml (hazard ratio [HR] 1.15, p < 0.001), and worse recurrence-free survival above 200-400 ml (HR 1.33, p = 0.01). Increased blood loss was associated with small bowel obstruction caused by colorectal cancer recurrence for blood loss higher than 400 ml (HR 1.97, p = 0.03) and 800 ml (HR 3.78, p = 0.02). CONCLUSIONS: Increased operative blood loss may adversely impact short term and long-term postoperative outcomes. Measures should be taken to minimize operative blood loss during colorectal cancer surgery. Due to the uncertainty of evidence identified, further research, with standardised methodology, is required on this important subject.

A systematic review and network meta-analysis comparing energy devices used in colorectal surgery.

BACKGROUND: The aim of this study was to compare energy devices used for intraoperative hemostasis during colorectal surgery. METHODS: A systematic literature review and Bayesian network meta-analysis performed. MEDLINE, EMBASE, Science Citation Index Expanded, and Cochrane were searched from inception to August 11th 2021. Intraoperative outcomes were operative blood loss, operative time, conversion to open, conversion to another energy source. Postoperative outcomes were mortality, overall complications, minor complications and major complications, wound complications, postoperative ileus, anastomotic leak, time to first defecation, day 1 and 3 drainage volume, duration of hospital stay. RESULTS: Seven randomized controlled trials (RCTs) were included, reporting on 680 participants, comparing conventional hemostasis, LigaSure™, Thunderbeat® and Harmonic®. Harmonic® had fewer overall complications compared to conventional hemostasis. Operative blood loss was less with LigaSure™ (mean difference [MD] = 24.1 ml; 95% confidence interval [CI] - 46.54 to - 1.58 ml) or Harmonic® (MD = 24.6 ml; 95% CI - 42.4 to - 6.7 ml) compared to conventional techniques. Conventional hemostasis ranked worst for operative blood loss with high probability (p = 0.98). LigaSure™, Harmonic® or Thunderbeat® resulted in a significantly shorter mean operative time by 42.8 min (95% CI - 53.9 to - 31.5 min), 28.3 min (95% CI - 33.6 to - 22.6 min) and 26.1 min (95% CI - 46 to - 6 min), respectively compared to conventional electrosurgery. LigaSure™ resulted in a significantly shorter mean operative time than Harmonic® by 14.5 min (95% CI 1.9-27 min) and ranked first for operative time with high probability (p = 0.97). LigaSure™ and Harmonic® resulted in a significantly shorter mean duration of hospital stay compared to conventional electrosurgery of 1.3 days (95% CI - 2.2 to - 0.4) and 0.5 days (95% CI - 1 to - 0.1), respectively. LigaSure™ ranked as best for hospital stay with high probability (p = 0.97). Conventional hemostasis was associated with more wound complications than Harmonic® (odds ratio [OR] = 0.27; CI 0.08-0.92). Harmonic® ranked best with highest probability (p = 0.99) for wound complications. No significant differences between energy devices were identified for the remaining outcomes. CONCLUSIONS: LigaSure™, Thunderbeat® and Harmonic® may be advantageous for reducing operative blood loss, operative time, overall complications, wound complications, and duration of hospital stay compared to conventional techniques. The energy devices result in comparable perioperative outcomes and no device is superior overall. However, included RCTs were limited in number and size, and data were not available to compare all energy devices for all outcomes of interest.

Postoperative chemotherapy improves survival in patients with resected high-risk Stage II colorectal cancer: results of a systematic review and meta-analysis.

AIM: The aim was to assess the benefit of adjuvant chemotherapy in high-risk Stage II colorectal cancer. METHOD: A systematic literature review and meta-analysis was performed comparing survival in patients with resected Stage II colorectal cancer and high-risk features having postoperative chemotherapy vs no chemotherapy. RESULTS: Of 1031 articles screened, 29 were included, reporting on 183 749 participants. Adjuvant chemotherapy significantly improved overall survival [hazard ratio (HR) 0.61, P < 0.0001], disease-specific survival (HR = 0.73, P = 0.05) and disease-free survival (HR = 0.59, P < 0.0001) compared to no chemotherapy. Adjuvant chemotherapy significantly increased 5-year overall survival (OR = 0.53, P = 0.0008) and 5-year disease-free survival (OR = 0.50, P = 0.001). Overall survival and disease-free survival remained significantly prolonged during subgroup analysis of studies published from 2015 onwards (HR = 0.60, P < 0.0001; HR = 0.65, P = 0.0001; respectively), in patients with two or more high-risk features (HR = 0.59, P = 0.0001; HR = 0.70, P = 0.03; respectively) and in colon cancer (HR = 0.61, P < 0.0001; HR = 0.51, P = 0.0001; respectively). Overall survival, disease-specific survival and disease-free survival during subgroup analysis of individual high-risk features were T4 tumour (HR = 0.58, P < 0.0001; HR = 0.50, P = 0.003; HR = 0.75, P = 0.05), < 12 lymph nodes harvested (HR = 0.67, P = 0.0002; HR = 0.80, P = 0.17; HR = 0.72, P = 0.02), poor differentiation (HR = 0.84, P = 0.35; HR = 0.85, P = 0.23; HR = 0.61, P = 0.41), lymphovascular or perineural invasion (HR = 0.55, P = 0.05; HR = 0.59, P = 0.11; HR = 0.76, P = 0.05) and emergency surgery (HR = 0.60, P = 0.02; HR = 0.68, P = 0.19). CONCLUSION: Adjuvant chemotherapy in high-risk Stage II colorectal cancer results in a modest survival improvement and should be considered on an individual patient basis. Due to potential heterogeneity and selection bias of the included studies, and lack of separate rectal cancer data, further large randomized trials with predefined inclusion criteria and standardized chemotherapy regimens are required.

A systematic review and meta-analysis comparing adverse events and functional outcomes of different pouch designs after restorative proctocolectomy.

AIM: There is no consensus as to which ileoanal pouch design provides better outcomes after restorative proctocolectomy. This study compares different pouch designs. METHOD: A systematic review of the literature was performed. A random effects meta-analytical model was used to compare adverse events and functional outcome. RESULTS: Thirty comparative studies comparing J, W, S and K pouch designs were included. No significant differences were identified between the different pouch designs with regard to anastomotic dehiscence, anastomotic stricture, pelvic sepsis, wound infection, pouch fistula, pouch ischaemia, perioperative haemorrhage, small bowel obstruction, pouchitis and sexual dysfunction. The W and K designs resulted in fewer cases of pouch failure compared with the J and S designs. J pouch construction resulted in a smaller maximum pouch volume compared with W and K pouches. Stool frequency per 24 h and during daytime was higher following a J pouch than W, S or K constructions. The J design resulted in increased faecal urgency and seepage during daytime compared with the K design. The use of protective pads during daytime and night-time was greater with a J pouch compared to S or K. The use of antidiarrhoeal medication was greater after a J reservoir than a W reservoir. Difficulty in pouch evacuation requiring intubation was higher with an S pouch than with W or J pouches. CONCLUSION: Despite its ease of construction and comparable complication rates, the J pouch is associated with higher pouch failure rates and worse function. Patient characteristics, technical factors and surgical expertise should be considered when choosing pouch design.