The liver has various functions, including the production and storage of substances necessary for the sustenance of life. It processes toxic substances (including those that are produced within the body because of the breakdown of old red cells) and plays a role in the excretion of these processed toxic substances. It produces bile, which contains substances necessary for the digestion of food. The bile is temporarily stored in the gallbladder and reaches the small bowel via the bile duct, usually in response to a stimulus such as ingestion of fatty food. The processed toxic substances are transported in the bile. These processed toxic substances are eventually excreted when the person opens his or her bowel. When there is obstruction to the flow of bile, the breakdown products of red cells can accumulate and cause yellowish discolouration of the skin and other linings in the body such as the white of the eyeball and the undersurface of the tongue. This results in a form of jaundice called obstructive jaundice. The obstruction to the bile flow is usually caused by stones in the common bile duct. These stones can originate from the gallbladder or from common bile duct stones. The majority of such stones can be treated endoscopically. However, a small proportion of the stones require surgery for removal. Other major causes of biliary obstruction include narrowing of the bile duct resulting from inflammation caused by stones, injury to the bile duct during operations to remove the gallbladder, and cancer of the bile duct, pancreas (an organ situated behind and below the stomach that secretes the digestive juices necessary for the digestion of food in addition to containing the cells that secrete insulin in order to maintain blood sugar levels), or the upper part of the small bowel called the duodenum. Operative removal is currently the only curative treatment available for these cancers. Such operations are typically major operations. However, the presence of toxic substances because of obstruction to the bile flow can result in physiological disturbances. Some surgeons perform certain procedures to temporarily drain the bile before performing the major operation to remove biliary obstruction due to stones, inflammation, or cancer. These pre-operative procedures can be done endoscopically (by introducing an instrument equipped with a camera through the mouth and into the small intestine and then inserting a small drainage tube through that instrument and past the obstruction in the bile duct) or under X-ray or other forms of image guidance via the liver. However, other surgeons argue that the temporary procedures to drain the bile are not necessary and that one should perform surgery directly. We sought evidence from randomised clinical trials only regarding this controversy. Such studies, when conducted properly, provide the best evidence. Two authors independently identified the trials and obtained the information from the trials.
We included six trials involving 510 patients for this review. The number of patients included in the trials varied from 40 to 202. All trials had a high risk of bias, that is, the trials may overestimate benefits and underestimate harms. There was no significant difference in risk of death between the two groups. The rate of serious complications was higher in the patients who underwent biliary drainage prior to operation compared with those who underwent surgery directly. The quality of life was not reported in any trial. There was no significant difference in the length of hospital stay between the two groups. The costs were not reported in any of the trials. Based on the currently available best evidence, there is no justification for the use of routine drainage of bile before a major operation in patients with obstruction to the flow of bile. Routine biliary drainage should not be funded and may result in litigations. Furthermore, well designed trials with low risk of systematic errors and low risk of random errors (low risk of play of chance) may be necessary.
There is currently not sufficient evidence to support or refute routine pre-operative biliary drainage for patients with obstructive jaundice. Pre-operative biliary drainage may increase the rate of serious adverse events. So, the safety of routine pre-operative biliary drainage has not been established. Pre-operative biliary drainage should not be used in patients undergoing surgery for obstructive jaundice outside randomised clinical trials.
Patients with obstructive jaundice have various pathophysiological changes that affect the liver, kidney, heart, and the immune system. There is considerable controversy as to whether temporary relief of biliary obstruction prior to major definitive surgery (pre-operative biliary drainage) is of any benefit to the patient.
To assess the benefits and harms of pre-operative biliary drainage versus no pre-operative biliary drainage (direct surgery) in patients with obstructive jaundice (irrespective of a benign or malignant cause).
We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Clinical Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until February 2012.
We included all randomised clinical trials comparing biliary drainage followed by surgery versus direct surgery, performed for obstructive jaundice, irrespective of the sample size, language, and publication status.
Two authors independently assessed trials for inclusion and extracted data. We calculated the risk ratio (RR), rate ratio (RaR), or mean difference (MD) with 95% confidence intervals (CI) based on the available patient analyses. We assessed the risk of bias (systematic overestimation of benefit or systematic underestimation of harm) with components of the Cochrane risk of bias tool. We assessed the risk of play of chance (random errors) with trial sequential analysis.
We included six trials with 520 patients comparing pre-operative biliary drainage (265 patients) versus no pre-operative biliary drainage (255 patients). Four trials used percutaneous transhepatic biliary drainage and two trials used endoscopic sphincterotomy and stenting as the method of pre-operative biliary drainage. The risk of bias was high in all trials. The proportion of patients with malignant obstruction varied between 60% and 100%. There was no significant difference in mortality (40/265, weighted proportion 14.9%) in the pre-operative biliary drainage group versus the direct surgery group (34/255, 13.3%) (RR 1.12; 95% CI 0.73 to 1.71; P = 0.60). The overall serious morbidity was higher in the pre-operative biliary drainage group (60 per 100 patients in the pre-operative biliary drainage group versus 26 per 100 patients in the direct surgery group) (RaR 1.66; 95% CI 1.28 to 2.16; P = 0.0002). The proportion of patients who developed serious morbidity was significantly higher in the pre-operative biliary drainage group (75/102, 73.5%) in the pre-operative biliary drainage group versus the direct surgery group (37/94, 37.4%) (P < 0.001). Quality of life was not reported in any of the trials. There was no significant difference in the length of hospital stay (2 trials, 271 patients; MD 4.87 days; 95% CI -1.28 to 11.02; P = 0.12) between the two groups. Trial sequential analysis showed that for mortality only a small proportion of the required information size had been obtained. There seemed to be no significant differences in the subgroup of trials assessing percutaneous compared to endoscopic drainage.