The Influence of Somatostatin on Postoperative Outcome after Elective Pancreatic Surgery

Somatostatin analogues for pancreatic surgery

BACKGROUND

Pancreatic resections are associated with high morbidity (30% to 60%) and mortality (5%). Synthetic analogues of somatostatin are advocated by some surgeons to reduce complications following pancreatic surgery; however, their use is controversial.

OBJECTIVES

To determine whether prophylactic somatostatin analogues should be used routinely in pancreatic surgery.

SEARCH METHODS

We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 1), MEDLINE, EMBASE and Science Citation Index Expanded to February 2013.

SELECTION CRITERIA

We included randomised controlled trials comparing prophylactic somatostatin or one of its analogues versus no drug or placebo during pancreatic surgery (irrespective of language or publication status).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and independently extracted data. We analysed data with both the fixed-effect and random-effects models using Review Manager (RevMan). We calculated the risk ratio (RR), mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) based on an intention-to-treat or available case analysis. When it was not possible to perform either of the above, we performed a per protocol analysis.

MAIN RESULTS

We identified 21 trials (19 trials of high risk of bias) involving 2348 people. There was no significant difference in the perioperative mortality (RR 0.80; 95% CI 0.56 to 1.16; n = 2210) or the number of people with drug-related adverse effects between the two groups (RR 2.09; 95% CI 0.83 to 5.24; n = 1199). Quality of life was not reported in any of the trials. The overall number of participants with postoperative complications was significantly lower in the somatostatin analogue group (RR 0.70; 95% CI 0.61 to 0.80; n = 1903) but there was no significant difference in the re-operation rate (RR 1.26; 95% CI 0.58 to 2.70; n = 687) or hospital stay (MD -1.29 days; 95% CI -2.60 to 0.03; n = 1314) between the groups. The incidence of pancreatic fistula was lower in the somatostatin analogue group (RR 0.66; 95% CI 0.55 to 0.79; n = 2206). The proportion of these fistulas that were clinically significant was not mentioned in most trials. On inclusion of trials that clearly distinguished clinically significant fistulas, there was no significant difference between the two groups (RR 0.69; 95% CI 0.38 to 1.28; n = 292).

AUTHORS' CONCLUSIONS

Somatostatin analogues may reduce perioperative complications but do not reduce perioperative mortality. Further adequately powered trials with low risk of bias are necessary. Based on the current available evidence, somatostatin and its analogues are recommended for routine use in people undergoing pancreatic resection.

Somatostatin analogues for pancreatic surgery

BACKGROUND

Pancreatic resections are associated with high morbidity (30% to 60%) and mortality (5%). Synthetic analogues of somatostatin are advocated by some surgeons to reduce complications following pancreatic surgery, however their use is controversial.

OBJECTIVES

To determine whether prophylactic somatostatin analogues should be used routinely in pancreatic surgery.

SEARCH METHODS

We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 12), MEDLINE, EMBASE and Science Citation Index Expanded to December 2011.

SELECTION CRITERIA

We included randomised controlled trials comparing prophylactic somatostatin or one of its analogues versus no drug or placebo during pancreatic surgery (irrespective of language or publication status).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion and independently extracted data. We analysed data with both the fixed-effect and random-effects models using Review Manager (RevMan). We calculated the risk ratio (RR), mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) based on an intention-to-treat or available case analysis. When it was not possible to perform either of the above, we performed per protocol analysis.

MAIN RESULTS

We identified 19 trials (17 trials of high risk of bias) involving 2245 patients. There was no significant difference in the perioperative mortality (RR 0.80; 95% CI 0.56 to 1.16; N = 2210) or the number of patients with drug-related adverse effects between the two groups (RR 2.09; 95% CI 0.83 to 5.24; N = 1199). Quality of life was not reported in any of the trials. The overall number of patients with postoperative complications was significantly lower in the somatostatin analogue group (RR 0.69; 95% CI 0.60 to 0.79; N = 1858) but there was no significant difference in the re-operation rate (RR 1.26; 95% CI 0.58 to 2.70; N = 687) or hospital stay (MD -1.04 days; 95% CI -2.54 to 0.46; N = 1269) between the groups. The incidence of pancreatic fistula was lower in the somatostatin analogue group (RR 0.63; 95% CI 0.52 to 0.77; N = 2161). The proportion of these fistulas that were clinically significant was not mentioned in most trials. On inclusion of trials that clearly distinguished clinically significant fistulas, there was no significant difference between the two groups (RR 0.69; 95% CI 0.34 to 1.41; N = 247).

AUTHORS' CONCLUSIONS

Somatostatin analogues may reduce perioperative complications but do not reduce perioperative mortality. Further adequately powered trials with low risk of bias are necessary. Based on the current available evidence, somatostatin and its analogues are recommended for routine use in patients undergoing pancreatic resection.

Somatostatin analogues for pancreatic surgery

BACKGROUND

Pancreatic resections are associated with high morbidity (30% to 60%) and mortality (5%). Synthetic analogues of somatostatin are advocated by some surgeons to reduce complications following pancreatic surgery, however their use is controversial.

OBJECTIVES

To determine whether prophylactic somatostatin analogues should be used routinely in pancreatic surgery.

SEARCH STRATEGY

We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 4), MEDLINE, EMBASE and Science Citation Index Expanded to November 2009.

SELECTION CRITERIA

We included randomised controlled trials comparing prophylactic somatostatin or one of its analogues versus no drug or placebo during pancreatic surgery (irrespective of language or publication status).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion and independently extracted data. We analysed data with both the fixed-effect and the random-effects models using Review Manager (RevMan). We calculated the risk ratio (RR), mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) based on an intention-to-treat or available case analysis. When it was not possible to perform either of the above, we performed per protocol analysis.

MAIN RESULTS

We identified 17 trials (of high risk of bias) involving 2143 patients. The overall number of patients with postoperative complications was lower in the somatostatin analogue group (RR 0.71; 95% CI 0.62 to 0.82) but there was no difference in the perioperative mortality, re-operation rate or hospital stay between the groups. The incidence of pancreatic fistula was lower in the somatostatin analogue group (RR 0.64; 95% CI 0.53 to 0.78). The proportion of these fistulas that were clinically significant was not mentioned in most trials. On inclusion of trials that clearly distinguished clinically significant fistulas, there was no difference between the two groups (RR 0.69; 95% CI 0.34 to 1.41). Subgroup analysis revealed a shorter hospital stay in the somatostatin analogue group than the controls for patients with malignant aetiology (MD -7.57; 95% CI -11.29 to -3.84).

AUTHORS' CONCLUSIONS

Somatostatin analogues reduce perioperative complications but do not reduce perioperative mortality. In those undergoing pancreatic surgery for malignancy, they shorten hospital stay. Further adequately powered trials with low risk of bias are necessary. Based on the current available evidence, somatostatin and its analogues are recommended for routine use in patients undergoing pancreatic resection for malignancy. There is currently no evidence to support their routine use in pancreatic surgeries performed for other indications.

[Natural history of the pancreatic stump after duodenopancreatectomy of the pancreatic head]

Major complications following pancreaticoduodenectomy are thought to be chiefly associated with exocrine secretion of the pancreatic remnant which is not well known. This work aims to assess the exocrine secretion of the pancreatic remnant within the early post-operative period.

PATIENTS AND METHODS

Seventy-five patients undergoing pancreaticoduodenectomy for presumed tumour were included in a prospective multicentre study. A tube was inserted in the pancreatic duct at the time of construction of the pancreatic anastomosis. Peripancreatic drainage was routinely used. Pancreatic juice and peripancreatic drainage fluid were collected and measured and pancreatic enzyme monitored. For 7 days patients received total parenteral nutrition and continuous infusion of randomly Somatostatin 14 (S-14) at a dose of 6 mg/24 h (days 1-6) and 3 mg/24 h (day 7) or matching placebo. Pancreatic fistula was defined as a daily drainage of more than 100 cc of amylase-rich fluid after day 3, persisting after day 12 or associated with symptoms or needing specific treatment.

RESULTS

Daily output of pancreatic juice was low during the first postoperative day and then increased gradually until day 5. A high enzyme concentration was observed in pancreatic juice on the first post-operative day. S-14 infusion resulted in a significant decrease of both pancreatic fistula rate and enzyme concentration in peripancreatic fluid.

CONCLUSIONS

During the first postoperative days, the outflow of the exocrine secretion of the pancreatic remnant is low but contains a high enzyme concentration with significant leaks within the peripancreatic area. S-14 infusion results in a decrease of pancreatic juice leaks from the pancreatic remnant.

Randomized controlled multicentre trial of somatostatin infusion after pancreaticoduodenectomy

BACKGROUND

It remains debatable whether somatostatin can prevent pancreatic fistula and other pancreatic stump-related complications following pancreaticoduodenectomy. This study assessed the effects of somatostatin-14 (S-14) on pancreatic remnant exocrine secretion.

METHODS

This was a double-blind, randomized, placebo-controlled trial in patients undergoing pancreaticoduodenectomy for malignancy. Patients received a continuous infusion of S-14 (n = 38) or placebo (n = 37) for 7 days. Pancreatic juice and peripancreatic drainage fluid was collected and measured, and pancreatic enzymes were monitored daily. Postoperative complications were recorded.

RESULTS

S-14 infusion was associated with a decrease in median daily pancreatic juice and pancreatic amylase output. Amylase concentration and output in the peripancreatic drain fluid were significantly lower after S-14 infusion than in the control group (both P < 0.05). The incidence of clinical pancreatic fistula (two of 38 versus eight of 37; P < 0.05) and total pancreatic stump-related complications (five of 38 versus 12 of 37; P < 0.05) was lower in patients treated with S-14. Duration of hospital stay was shorter after S-14 (18 versus 26 days; P = 0.01).

CONCLUSION

Although the effect of S-14 on exocrine secretion remains difficult to demonstrate, it did reduce pancreatic juice leakage from the pancreatic remnant.