People who have more than two alcoholic drinks a day may be TWICE as likely to die after surgery People who drink heavily are more likely to suffer complications after surgery than those who abstain Most common problems are infection and slow healing People who drink are 73% more likely to get infection and 80% more likely to have breathing difficulties Could be because heavy alcohol consumption compromises the immune system People who have more than two alcoholic drinks a day are more likely to suffer complications after surgery People who have more than two alcoholic drinks a day are more likely to suffer complications after surgery than light drinkers. Infections and slow wound healing were the most common complications associated with heavy drinking, according to lead author Marie Eliasen of the National Institute of Public Health at the University of Southern Denmark in Copenhagen. She and her co-authors examined the results of 55 studies on pre-operation drinking and post-operation complications occurring up to 30 days after surgery. The studies looked at head and neck, abdominal and orthopaedic surgeries for a variety of conditions, none of which was related to alcohol use. Patients who drank heavily leading up to surgery, including those who abused alcohol or were dependent on it, were more than twice as likely to die in the month after their procedures than abstainers - though the risk of dying varied greatly by procedure. Heavy drinkers were also 73 per cent more likely to contract a post-operation infection, 80 per cent more likely to have difficulty breathing and 29 per cent more likely to be admitted to the intensive care unit than non-drinkers, according to results published in the Annals of Surgery. The associations were stronger with abdominal surgery - which can include gallbladder, liver and stomach procedures - than with other types of operations. Low to moderate drinking - a drink or two per day or less - was not tied to post-op complications, but only a few studies addressed that group, Ms Eliasen told Reuters Health. Heavy alcohol use over time compromises the immune system, which makes the body more susceptible to infections, she said. "Moreover, high alcohol consumption increases the endocrine stress response to surgery which may worsen existing conditions and reduces blood coagulation giving an increased risk of bleeding, and slowing down wound healing processes," she said. The studies looked at alcohol consumption over different lengths of time, from months to years, so it's unclear what duration of alcohol use leads to higher risks or when a patient's drinking has the strongest effects. Patients who drink heavily in the lead up to surgery are more than twice as likely to die in the month after their procedures than abstainers But it's likely that the more you drink, the quicker the extra risks would appear, Ms Eliasen said. A previous study found that post-operation risks declined when patients stopped drinking four or more weeks before surgery, she added. Though it may seem like common sense, sometimes doctors don't advise their patients to stop drinking before an operation, she added. The analysis confirms that "alcohol and surgery are a bad combination," Professor Bolette Pedersen of the Clinical Health Promotion Centre of Bispebjerg and Frederiksberg University Hospital in Denmark, said. But it's not clear what effect stopping drinking before surgery would have on complications, said Professor Pedersen, who was not involved in the review. Few patients are offered specific stop-drinking programmes as part of the lead up to surgery, she added. It's much more common that patients are encouraged to stop smoking. "In my opinion, it is now time to focus on intervention studies (randomised trials) to evaluate the effects of stop-drinking in relation to surgery," she said.