human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background This prospect i ve study followed patients who underwent breast reductions  to determine the influence of smoking and the amount of tissue removed on postoperative wound infections . Methods Patients who had received breast reductions were considered eligible for the study . The study excluded postbariatric patients and those with ongoing clinical infections , a recent antibiotic course , or systemic diseases that could impair tissue oxygenation . Smokers were instructed to quit smoking at least 4 weeks before surgery . Results By March 2004 , the study had enrolled 87 patients .  Postoperative infections were present in 24 cases ( 27.9 % ) . Infections included 16 in smokers ( 37.2 % ) , 8 in nonsmokers ( 18.2 % ; p < 0.05 ) , 14 in patients with large resections ( > 0.85 kg ; 70 % ) , and 10 in patients with small resections ( 14.9 % ; p < 0.001 ) . Significant differences were found between the patients who experienced infections and those who were infection free in terms of the overall estimated cigarettes smoked ( mean , 146,000 ; range , 29,200–228,125 vs mean , 10,950 ; range , 9,125–54,750 ; p < 0.001 ) , the number of pack years ( mean , 20 ; range , 4–31 vs mean , 2 ; range , 1–8 ; p < 0.001 ) , and the amount of tissue removed ( mean , 0.9 kg ; range , 0.5–2 kg vs mean , 0.5 kg ; range , 0.2–1.4 kg ; p < 0.001 ) . The analysis for all the patients determined an odds ratio of 2.04 for smoking and 4.7 for the amount of tissue removed . Conclusions Smoking and the amount of tissue removed are important issues in aesthetic breast surgery that need to be addressed accurately by the plastic surgeon . If future larger studies confirm these data , surgeons could have a simple and easy method for stratifying patients according to their risk for the development of wound infections and for prescribing specific preventive measures Background : In this prospect i ve study , the authors followed patients who underwent aesthetic abdominoplasty  to determine the influence of smoking on the occurrence of postoperative wound infections . Methods : Patients who underwent aesthetic abdominoplasty were considered eligible for the study . The authors excluded postbariatric patients , those with ongoing clinical infections , those receiving a recent antibiotic course , and those with systemic diseases such as arteriosclerosis and diabetes mellitus . Smokers were advised to quit smoking at least 4 weeks before surgery . Results : Starting in February of 2004 , the authors enrolled 84 patients .  Postoperative infections were present in 13 patients ( 15.5 percent ) and were superficial in 10 ( 77 percent ) . All but one occurred in smokers . These had a certain number of cigarettes smoked per day , years of smoking , and higher estimated overall number of smoked cigarettes when postoperative infections were present . The relative risk of smoking on infections was 12 . A cutoff value of approximately 33,000 overall cigarettes smoked determined 3.3 percent false-positive and 0 percent false-negative rates . Conclusions : Smoking is an important issue in aesthetic surgery that needs to be accurately addressed during the preoperative interview . In the future , the analysis of smoke-related , easy-to-gather variables such as the estimated overall number of cigarettes smoked until surgery could help stratify patients according to their risk of manifesting infections Background The extent to which lifestyle factors such as tobacco consumption and obesity affect the outcome after inguinal hernia surgery has been poorly studied . This study was undertaken to assess the effect of smoking , smokeless tobacco consumption and obesity on postoperative complications after inguinal hernia surgery . The second aim was to evaluate the effect of tobacco consumption and obesity on the length of hospital stay . Methods A cohort of 12,697 Swedish construction workers with prospect ively collected exposure data on tobacco consumption and body mass index ( BMI ) from 1968 onward were linked to the Swedish inpatient register . Information on inguinal hernia procedures was collected from the inpatient register . Any postoperative complication occurring within 30 days was registered . In addition to this , the length of hospitalization was calculated . The risk of postoperative complications due to tobacco exposure and BMI was estimated using a multiple logistic regression model and the length of hospital stay was estimated in a multiple linear regression model . Results After adjusting for the other covariates in the multivariate analysis , current smokers had a 34 % ( OR 1.34 , 95 % CI 1.04 , 1.72 ) increased risk of postoperative complications compared to never smokers . Use of “ Swedish oral moist snuff ” ( snus ) and pack-years of tobacco smoking were not found to be significantly associated with an increased risk of postoperative complications . BMI was found to be significantly associated with an increased risk of postoperative complications ( P = 0.04 ) . This effect was mediated by the underweighted group ( OR 2.94 ; 95 % CI 1.15 , 7.51 ) . In a multivariable model , increased BMI was also found to be significantly associated with an increased mean length of hospital stay ( P < 0.001 ) . There was no statistically significant association between smoking or using snus , and the mean length of hospitalization after adjusting for the other covariates in the model . ConclusionS moking increases the risk of postoperative complications even in minor surgery such as inguinal hernia procedures . Obesity increases hospitalization after inguinal hernia surgery . The Swedish version of oral moist tobacco , snus , does not seem to affect the complication rate after hernia surgery at all BACKGROUND Previous studies have linked smoking and alcohol consumption to a considerable disease burden and large healthcare expenditures . However , findings from studies based on individual level data are sparse and inconclusive . Our objective was to assess the association between alcohol consumption , smoking and patterns of hospitalization , defined as admission and duration of hospitalization . METHODS The study was based on 12 698 men and women , aged 20 years or more , enrolled in the Copenhagen City Heart Study . We related  smoking and alcohol  to hospital admission from any cause , smoking- and alcohol-related diseases and duration of hospitalization in a two-part r and om effects model . RESULTS Smoking status was strongly associated with admission and duration of hospitalization . For smoking-related admissions , odds ratios ( OR ) of 2.77 ( 95 % CI 2.13 - 3.59 ) in men and 6.30 ( 95 % CI 4.80 - 8.26 ) in women were observed among smokers of > 20 g/day compared to never-smokers . For any admission ( excl . smoking-related causes ) , corresponding ORs were 1.32 ( 95 % CI 1.15 - 1.51 ) and 1.80 ( 95 % CI 1.58 - 2.06 ) , respectively . In men , a U-shaped association between alcohol consumption and risk of admission was found , both regarding any admission and admissions due to alcohol-related diseases . Alcohol was associated with alcohol-related admissions in women but not with duration of hospitalization . CONCLUSIONS Smoking was associated with increased risk of hospital admission and duration of hospitalization . A U-shaped relation was observed for alcohol consumption and risk of hospitalization in men , but no effect on duration was observed . In women , however , alcohol consumption was only vaguely associated with admission and duration of hospitalization BACKGROUND An association between smoking and impaired wound healing has been reported in retrospective studies . The smoking status of a surgical patient may be confounded by social and medical parameters . We have evaluated the effect of smoking in a test wound in volunteers , with special reference to a reliable scientific match between smokers and nonsmokers . METHODS In a prospect i ve open study with blinded assessment , 19 smoking ( 20 cigarettes/day ) and 18 nonsmoking healthy volunteers were matched with respect to baseline characteristics . The deposition of total protein and mature collagen ( expressed as hydroxyproline ) was assessed in an exp and ed polytetrafluoroethylene wound healing model implanted subcutaneously for 10 days . RESULTS The nonsmokers had a 1.8 times higher median amount of hydroxyproline than the smokers ( p < 0.01 ) . The deposition of hydroxyproline was negatively correlated with the consumption of tobacco both before ( r = -0.44 ; p < 0.01 ) and during the study ( r = -0.48 ; p < 0.005 ) . The impairment was specific for the production of collagenous proteins and not other proteins . CONCLUSIONS The synthesis of subcutaneous collagen in smokers is specifically impeded , indicating an impaired wound-healing process . Because mature collagen is the main determinator of strength of an operative wound , the results support the view that patients should be advised to stop smoking before an operation BACKGROUND Coughing during emergence from general anaesthesia may be detrimental , particularly after cervical spine surgery . We compared the effect of propofol or sevoflurane anaesthesia on the incidence and severity of coughing during recovery in patients undergoing cervical spine surgery via an anterior approach . As a secondary aim , we also evaluated the influences of smoking and estimated residual anaesthetic agent concentrations on coughing . METHODS Thirty-four patients were enrolled in a r and omized prospect i ve , double-blind study to receive either propofol ( PPF ) or sevoflurane ( SEVO ) for maintenance of anaesthesia . The decision to perform tracheal extubation was based on specified criteria , including resumption of spontaneous respiration and consciousness . During emergence from anaesthesia and extubation , coughing was observed and grade d at predefined times . RESULTS The incidence of severe coughing was higher in the SEVO group than in the PPF group ( 59 % and 6 % , respectively ) , and also in smokers than in non-smokers ( 50 % and 17 % , respectively ) . The peak incidence of coughing was at tracheal extubation . The probability of coughing was influenced by the estimated residual concentration of anaesthetic agents at extubation , except for smokers in the SEVO group who were at the highest risk of coughing . CONCLUSIONS The incidence of coughing after cervical spine surgery when tracheal extubation is performed according to clinical criteria is lower after propofol anaesthesia compared with sevoflurane anaesthesia . Smokers are at increased risk of coughing , independently of the type of anaesthesia maintenance . Higher residual concentrations of anaesthetic agents decrease the probability of coughing , except for smokers anaesthetized with sevoflurane HYPOTHESIS Anastomotic leaks following elective colorectal resections increase morbidity , mortality , and the need for additional interventions . An accurate underst and ing of risk factors would potentially reduce anastomotic leaks and /or allow appropriate selection of patients for diverting stomas . DESIGN Prospect i ve review of patient and operative characteristics that contribute to anastomotic leaks . SETTING Fifty-one sites within the United States ( May 2002-March 2005 ) . PATIENTS Six hundred seventy-two patients who participated in a trial comparing preoperative antimicrobials in elective open colorectal surgery .  MAIN OUTCOME MEASURES Anastomotic leaks were diagnosed using clinical findings and were confirmed with imaging . We examined 20 variables possibly affecting anastomotic healing in univariate and multivariate analyses . RESULTS There were 24  anastomotic leaks in 672 patients ( 3.6 % ) undergoing elective colorectal resection . There were 10 deaths ( 1.5 % ) . A baseline albumin level of less than 3.5 g/dL ( to convert to grams per liter , multiply by 10 ) ( P = .04 ) and male sex ( P = .03 ) were associated with anastomotic leaks in both univariate and multivariate analyses ( adjusted odds ratios , 2.56 and 3.12 , respectively ) . Increased duration of surgery ( SD , 60 minutes ; odds ratio , 1.53 ; 95 % confidence interval , 1.06 - 2.22 ; P = .03 ) and steroid use at the time of surgery ( odds ratio , 3.85 ; 95 % confidence interval , 1.24 - 11.93 ; P = .02 ) were significant in univariate analysis . Surgical procedure with rectal resection ; prophylaxis with ertapenem ( vs cefotetan ) ; or history of obesity , tobacco use , or diabetes was not associated with anastomotic leaks . CONCLUSIONS Significant risk factors for anastomotic leaks include low preoperative serum albumin level , steroid use , male sex , and increased duration of surgery . Appreciation of risk factors provides a rational basis for temporary diversion OBJECTIVES The overall benefit of  carotid endarterectomy ( CEA )  is dependent on the outcome from the procedure . However , many reports are from selected centres and not population -based . The aim of this study 
    Output:
    
agent
Preoperative smoking status was not observed to be associated with postoperative mortality , cardiovascular complications , bleedings , anastomotic leakage , or allograft rejection .
CONCLUSIONS Preoperative smoking was found to be associated with an increased risk of the following postoperative complications : general morbidity , wound complications , general infections , pulmonary complications , neurological complications , and admission to the intensive care unit
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background This prospect i ve study followed patients who underwent breast reductions  to determine the influence of smoking and the amount of tissue removed on postoperative wound infections . Methods Patients who had received breast reductions were considered eligible for the study . The study excluded postbariatric patients and those with ongoing clinical infections , a recent antibiotic course , or systemic diseases that could impair tissue oxygenation . Smokers were instructed to quit smoking at least 4 weeks before surgery . Results By March 2004 , the study had enrolled 87 patients .  Postoperative infections were present in 24 cases ( 27.9 % ) . Infections included 16 in smokers ( 37.2 % ) , 8 in nonsmokers ( 18.2 % ; p < 0.05 ) , 14 in patients with large resections ( > 0.85 kg ; 70 % ) , and 10 in patients with small resections ( 14.9 % ; p < 0.001 ) . Significant differences were found between the patients who experienced infections and those who were infection free in terms of the overall estimated cigarettes smoked ( mean , 146,000 ; range , 29,200–228,125 vs mean , 10,950 ; range , 9,125–54,750 ; p < 0.001 ) , the number of pack years ( mean , 20 ; range , 4–31 vs mean , 2 ; range , 1–8 ; p < 0.001 ) , and the amount of tissue removed ( mean , 0.9 kg ; range , 0.5–2 kg vs mean , 0.5 kg ; range , 0.2–1.4 kg ; p < 0.001 ) . The analysis for all the patients determined an odds ratio of 2.04 for smoking and 4.7 for the amount of tissue removed . Conclusions Smoking and the amount of tissue removed are important issues in aesthetic breast surgery that need to be addressed accurately by the plastic surgeon . If future larger studies confirm these data , surgeons could have a simple and easy method for stratifying patients according to their risk for the development of wound infections and for prescribing specific preventive measures Background : In this prospect i ve study , the authors followed patients who underwent aesthetic abdominoplasty  to determine the influence of smoking on the occurrence of postoperative wound infections . Methods : Patients who underwent aesthetic abdominoplasty were considered eligible for the study . The authors excluded postbariatric patients , those with ongoing clinical infections , those receiving a recent antibiotic course , and those with systemic diseases such as arteriosclerosis and diabetes mellitus . Smokers were advised to quit smoking at least 4 weeks before surgery . Results : Starting in February of 2004 , the authors enrolled 84 patients .  Postoperative infections were present in 13 patients ( 15.5 percent ) and were superficial in 10 ( 77 percent ) . All but one occurred in smokers . These had a certain number of cigarettes smoked per day , years of smoking , and higher estimated overall number of smoked cigarettes when postoperative infections were present . The relative risk of smoking on infections was 12 . A cutoff value of approximately 33,000 overall cigarettes smoked determined 3.3 percent false-positive and 0 percent false-negative rates . Conclusions : Smoking is an important issue in aesthetic surgery that needs to be accurately addressed during the preoperative interview . In the future , the analysis of smoke-related , easy-to-gather variables such as the estimated overall number of cigarettes smoked until surgery could help stratify patients according to their risk of manifesting infections Background The extent to which lifestyle factors such as tobacco consumption and obesity affect the outcome after inguinal hernia surgery has been poorly studied . This study was undertaken to assess the effect of smoking , smokeless tobacco consumption and obesity on postoperative complications after inguinal hernia surgery . The second aim was to evaluate the effect of tobacco consumption and obesity on the length of hospital stay . Methods A cohort of 12,697 Swedish construction workers with prospect ively collected exposure data on tobacco consumption and body mass index ( BMI ) from 1968 onward were linked to the Swedish inpatient register . Information on inguinal hernia procedures was collected from the inpatient register . Any postoperative complication occurring within 30 days was registered . In addition to this , the length of hospitalization was calculated . The risk of postoperative complications due to tobacco exposure and BMI was estimated using a multiple logistic regression model and the length of hospital stay was estimated in a multiple linear regression model . Results After adjusting for the other covariates in the multivariate analysis , current smokers had a 34 % ( OR 1.34 , 95 % CI 1.04 , 1.72 ) increased risk of postoperative complications compared to never smokers . Use of “ Swedish oral moist snuff ” ( snus ) and pack-years of tobacco smoking were not found to be significantly associated with an increased risk of postoperative complications . BMI was found to be significantly associated with an increased risk of postoperative complications ( P = 0.04 ) . This effect was mediated by the underweighted group ( OR 2.94 ; 95 % CI 1.15 , 7.51 ) . In a multivariable model , increased BMI was also found to be significantly associated with an increased mean length of hospital stay ( P < 0.001 ) . There was no statistically significant association between smoking or using snus , and the mean length of hospitalization after adjusting for the other covariates in the model . ConclusionS moking increases the risk of postoperative complications even in minor surgery such as inguinal hernia procedures . Obesity increases hospitalization after inguinal hernia surgery . The Swedish version of oral moist tobacco , snus , does not seem to affect the complication rate after hernia surgery at all BACKGROUND Previous studies have linked smoking and alcohol consumption to a considerable disease burden and large healthcare expenditures . However , findings from studies based on individual level data are sparse and inconclusive . Our objective was to assess the association between alcohol consumption , smoking and patterns of hospitalization , defined as admission and duration of hospitalization . METHODS The study was based on 12 698 men and women , aged 20 years or more , enrolled in the Copenhagen City Heart Study . We related  smoking and alcohol  to hospital admission from any cause , smoking- and alcohol-related diseases and duration of hospitalization in a two-part r and om effects model . RESULTS Smoking status was strongly associated with admission and duration of hospitalization . For smoking-related admissions , odds ratios ( OR ) of 2.77 ( 95 % CI 2.13 - 3.59 ) in men and 6.30 ( 95 % CI 4.80 - 8.26 ) in women were observed among smokers of > 20 g/day compared to never-smokers . For any admission ( excl . smoking-related causes ) , corresponding ORs were 1.32 ( 95 % CI 1.15 - 1.51 ) and 1.80 ( 95 % CI 1.58 - 2.06 ) , respectively . In men , a U-shaped association between alcohol consumption and risk of admission was found , both regarding any admission and admissions due to alcohol-related diseases . Alcohol was associated with alcohol-related admissions in women but not with duration of hospitalization . CONCLUSIONS Smoking was associated with increased risk of hospital admission and duration of hospitalization . A U-shaped relation was observed for alcohol consumption and risk of hospitalization in men , but no effect on duration was observed . In women , however , alcohol consumption was only vaguely associated with admission and duration of hospitalization BACKGROUND An association between smoking and impaired wound healing has been reported in retrospective studies . The smoking status of a surgical patient may be confounded by social and medical parameters . We have evaluated the effect of smoking in a test wound in volunteers , with special reference to a reliable scientific match between smokers and nonsmokers . METHODS In a prospect i ve open study with blinded assessment , 19 smoking ( 20 cigarettes/day ) and 18 nonsmoking healthy volunteers were matched with respect to baseline characteristics . The deposition of total protein and mature collagen ( expressed as hydroxyproline ) was assessed in an exp and ed polytetrafluoroethylene wound healing model implanted subcutaneously for 10 days . RESULTS The nonsmokers had a 1.8 times higher median amount of hydroxyproline than the smokers ( p < 0.01 ) . The deposition of hydroxyproline was negatively correlated with the consumption of tobacco both before ( r = -0.44 ; p < 0.01 ) and during the study ( r = -0.48 ; p < 0.005 ) . The impairment was specific for the production of collagenous proteins and not other proteins . CONCLUSIONS The synthesis of subcutaneous collagen in smokers is specifically impeded , indicating an impaired wound-healing process . Because mature collagen is the main determinator of strength of an operative wound , the results support the view that patients should be advised to stop smoking before an operation BACKGROUND Coughing during emergence from general anaesthesia may be detrimental , particularly after cervical spine surgery . We compared the effect of propofol or sevoflurane anaesthesia on the incidence and severity of coughing during recovery in patients undergoing cervical spine surgery via an anterior approach . As a secondary aim , we also evaluated the influences of smoking and estimated residual anaesthetic agent concentrations on coughing . METHODS Thirty-four patients were enrolled in a r and omized prospect i ve , double-blind study to receive either propofol ( PPF ) or sevoflurane ( SEVO ) for maintenance of anaesthesia . The decision to perform tracheal extubation was based on specified criteria , including resumption of spontaneous respiration and consciousness . During emergence from anaesthesia and extubation , coughing was observed and grade d at predefined times . RESULTS The incidence of severe coughing was higher in the SEVO group than in the PPF group ( 59 % and 6 % , respectively ) , and also in smokers than in non-smokers ( 50 % and 17 % , respectively ) . The peak incidence of coughing was at tracheal extubation . The probability of coughing was influenced by the estimated residual concentration of anaesthetic agents at extubation , except for smokers in the SEVO group who were at the highest risk of coughing . CONCLUSIONS The incidence of coughing after cervical spine surgery when tracheal extubation is performed according to clinical criteria is lower after propofol anaesthesia compared with sevoflurane anaesthesia . Smokers are at increased risk of coughing , independently of the type of anaesthesia maintenance . Higher residual concentrations of anaesthetic agents decrease the probability of coughing , except for smokers anaesthetized with sevoflurane HYPOTHESIS Anastomotic leaks following elective colorectal resections increase morbidity , mortality , and the need for additional interventions . An accurate underst and ing of risk factors would potentially reduce anastomotic leaks and /or allow appropriate selection of patients for diverting stomas . DESIGN Prospect i ve review of patient and operative characteristics that contribute to anastomotic leaks . SETTING Fifty-one sites within the United States ( May 2002-March 2005 ) . PATIENTS Six hundred seventy-two patients who participated in a trial comparing preoperative antimicrobials in elective open colorectal surgery .  MAIN OUTCOME MEASURES Anastomotic leaks were diagnosed using clinical findings and were confirmed with imaging . We examined 20 variables possibly affecting anastomotic healing in univariate and multivariate analyses . RESULTS There were 24  anastomotic leaks in 672 patients ( 3.6 % ) undergoing elective colorectal resection . There were 10 deaths ( 1.5 % ) . A baseline albumin level of less than 3.5 g/dL ( to convert to grams per liter , multiply by 10 ) ( P = .04 ) and male sex ( P = .03 ) were associated with anastomotic leaks in both univariate and multivariate analyses ( adjusted odds ratios , 2.56 and 3.12 , respectively ) . Increased duration of surgery ( SD , 60 minutes ; odds ratio , 1.53 ; 95 % confidence interval , 1.06 - 2.22 ; P = .03 ) and steroid use at the time of surgery ( odds ratio , 3.85 ; 95 % confidence interval , 1.24 - 11.93 ; P = .02 ) were significant in univariate analysis . Surgical procedure with rectal resection ; prophylaxis with ertapenem ( vs cefotetan ) ; or history of obesity , tobacco use , or diabetes was not associated with anastomotic leaks . CONCLUSIONS Significant risk factors for anastomotic leaks include low preoperative serum albumin level , steroid use , male sex , and increased duration of surgery . Appreciation of risk factors provides a rational basis for temporary diversion OBJECTIVES The overall benefit of  carotid endarterectomy ( CEA )  is dependent on the outcome from the procedure . However , many reports are from selected centres and not population -based . The aim of this study 
    Output:
    