***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: The leading cause of postoperative morbidity in patients undergoing major head and neck surgical procedures is postoperative infection . This prospect i ve r and omized multi-institutional clinical trial was design ed to compare the effectiveness of clindamycin phosphate and high-dose cefazolin sodium therapy in preventing postoperative wound sepsis in patients undergoing contaminated head and neck surgical procedures in which flap reconstruction was required . Either clindamycin phosphate ( 900 mg ) or cefazolin sodium ( 2 g ) therapy was instituted intravenously prior to surgery and continued every 8 hours , for a total of 24 hours . The patients received postoperative follow-up , and the wounds were grade d according to the worst condition observed . One hundred cases were evaluated . Fifty-one patients received clindamycin and 49 patients received high doses of cefazolin ;  wound infection developed in 10 patients ( 19.6 % ) and 11 patients ( 21.6 % ) , respectively . This difference was not statistically significant . The average duration of surgery was approximately 8 hours for both the infected and the noninfected groups of patients . High-dose cefazolin and clindamycin have similar efficacy when administered prophylactically under these circumstances . Reconstruction with free vascularized tissue may aid in reducing postoperative wound infection Ampicillin plus Cloxacillin ( 2 gm of each daily ) or a placebo were given at r and om and on a double blind basis to 52 and 50 patients undergoing oral , laryngeal or pharyngeal surgery for neoplastic lesions . The frequency of postoperative wound and respiratory infections was significantly higher ( p < 0.05 ) among the placebo-treated patients . Most infections in both groups were caused by gram-negative rods . No untoward effects were related to the use of ampicillin plus cloxacillin and this form of therapy did not increase the rate of pharyngeal or wound asymptomatic colonization by bacteria A r and omized , placebo-controlled , double-blinded trial of cefam and ole in the prophylaxis of infection after major head and neck surgery was performed . Patients were given the drug on call to the operating room , and again four and eight hours after the initial dose . Twenty of 25 patients were evaluable .  Wound infection developed in five of nine placebo recipients ( 55 % ) , and three of 11 ( 33 % ) receiving cefam and ole .  Mean duration of hospitalization was 91.1 days in the placebo group , 34.3 in the cefam and ole group ( p less than 0.05 ) . The study was stopped because of excessive morbidity in the placebo group . Cefam and ole decreases the duration of hospitalization following major head and neck cancer surgery Objective The aim of this study was to identify risk factors for surgical-site infections ( SSIs ) in patients with head and neck cancer su bmi tted to major clean-contaminated surgery . Study Design This is a prospect i ve study conducted in a tertiary cancer center hospital . Subjects and Methods This study includes 258 patients su bmi tted to a major clean-contaminated head and neck oncologic surgery .  Results The overall SSI rate was 38.8 % . The univariate analysis showed the following significant risk factors : race , tobacco consumption , clinical stage , comorbidities , time duration of the surgical procedure , and flap reconstruction . The final model by logistic regression identified the following independent predictors for SSI : tobacco consumption ( odds ratio [ OR ] = 2.96 ) , presence of metastatic lymph nodes ( OR = 2.05 ) , flap reconstruction ( OR = 2.20 ) , and antimicrobial prophylaxis exceeding 48 hours ( OR=1.89 ) . Conclusion The high-risk patients for SSI in head and neck oncologic surgery were those with cancer at advanced stages , those who were smokers , those presenting comorbidities , those who needed major reconstruction of the surgical wound , or those who were su bmi tted to inadequate antibiotic prophylaxis The use of antibiotic prophylaxis in head and neck surgery is controversial . Most surgeons agree that when surgery requires entry into the aerodigestive tract through the skin the wound is by definition contaminated and antibiotic prophylaxis is indicated as it is in other contaminated wounds . There is no general agreement as to which antibiotic or combination of antibiotics to use or what the schedule of dosage administration should be . In order to obtain a meaningful data to help in decision making , a double blind , r and omized study was performed to investigate whether cefazolin alone or a combination of gentamicin and clindamycin was more effective in prophylaxis . All patients entered into the study underwent major oncologic head and neck surgery requiring entry into the upper aerodigestive tract through the skin . Patients were stratified at entry according to the stage of disease , surgical procedure , and the existence of a prior tracheotomy or prior radiation therapy . Subsequently , patients were r and omly assigned to 1 of 4 treatment groups . Group I : Cefazolin 1 day , placebo day 2 to 5 . Group II : Cefazolin days 1 to 5 , Group III : Gentamicin and clindamycin 1 day , placebo days 2 to 5 . Group IV : Gentamicin and clindamycin days 1 to 5 . Drugs were given intravenously beginning 3 hours preoperatively and continued postoperatively every 8 hours , according to the assigned schedule . All wounds were observed daily following surgery and were grade d on a predetermined scale by 3 unbiased observers . Significantly wound infections occurred in 15 % of all patients . Group I , 33 % ; Group II , 20 % ; Group III , 7 % ; Group IV , 4 % . In Group III and Group IV there was a statistically significant ( P less than .05 ) reduction in the rate of postoperative wound infection . Multifactorial analysis demonstrated that patients whose surgery included repair with a regional pectoral flap had a statistically significant increased chance of developing postoperative wound infection ( P less than .05 ) . Patients undergoing laryngectomy , with or without neck dissection , were at less risk of postoperative infection tham patients undergoing oropharyngeal resection ( P less than .05 ) . The preoperative existence of tracheotomy or prior radiation therapy had no demonstrable effect on the incidence of wound infection postoperatively in this study Context : Head and neck surgeries are complex . Wound complications are associated with considerable morbidity and can result in delay in the adjuvant treatment . Identification of factors will help in formulating preventive guidelines . Aims : The aim of this study is to identify perioperative factors responsible for wound complications . Setting s and Design : Prospect i ve study of 186 head and neck patients . Subjects and Methods : Pre-operative , intraoperative and post-operative factors were recorded . Each patient was evaluated for minor and major wound complications twice daily during the hospital stay . Statistical Analysis : Chi-square test was used for univariate and log regression test was used for multivariate analysis . Results : The overall wound complication rate was 29 % with 7 % major and 22 % minor complications . On univariate analysis , laryngeal and hypopharyngeal location , advanced T stage , poor oral hygiene , clean-contaminated surgery , low Karnofsky performance status ( KPS ) , flap reconstruction , blood loss more than 1000 ml , perioperative blood transfusion , duration of surgery greater than 4.3 h and post-operative hemoglobin lesser than 11 g% , post-operative tracheostomy and resection of m and ible were statistical significant factors . On multivariate analysis , post-operative tracheostomy , low KPS , post-operative serum albumin less than 3.7 g/dl and duration of surgery greater than 4.3 h were significant factors . Conclusion : Apart from unavoidable factors , it is essential to take care of certain factors viz nutrition , haemoglobin , oral hygiene , asepsis and repeating antibiotics in prolonged surgery The aim of our study was to evaluate the optimal duration of antibiotic prophylaxis in major oncologic surgery of the head and neck using a novel broad spectrum drug combination : clindamycin and cefonicid . A prospect i ve r and omized study was carried out on 126 evaluable patients undergoing clean-contaminated ( skin to mucosa ) surgery for cancer of larynx , pharynx or oral cavity . Cases at high surgical risk ( because of need of pedicled or microvascular free flaps reconstruction ) , were excluded from the study . Within 20 days after surgery , only one case of wound infection was recorded among the 62 patients treated with the one-day schedule , versus three cases registered among the 64 subjects receiving three-day chemoprophylaxis . Episodes of systemic infections and eventual wound complications occurring in the first 20 days after surgery have also been recorded . The role of potential risk factors for postoperative complications has been evaluated . According to our findings , a three-day antibiotic regimen is not more effective than a short-term ( one-day ) schedule in preventing wound or systemic infection in clean-contaminated head and neck cancer surgery without flap reconstruction BACKGROUND Patients requiring major oncologic head and neck surgery are at high risk for postoperative wound infection when the surgical site is contaminated by secretions from the upper aerodigestive tract . Studies to identify agents active in the prevention of postoperative wound infection may serve to reduce patient morbidity . METHODS Patients scheduled for a major contaminated head and neck surgical procedure were r and omly assigned to receive either ampicillin/sulbactam or clindamycin . Medication was administered 1 to 2 hours prior to surgery and every 6 hours , for a total of five doses . Postoperatively , patients were followed daily for the development of wound infection or other septic complication . RESULTS A total of 242 patients were enrolled in the study ; 119 received ampicillin/sulbactam , and 123 received clindamycin .  A total of 169 patients were considered evaluable . Of the evaluable patients , 14 % in each group developed a postoperative wound infection . There were no statistically significant differences between the number of days to onset of wound infection , nor was there a statistically significant difference in the rate of non-wound infections in the two groups . There were no statistically significant differences between the intent to treat group and the evaluable group of patients . CONCLUSION It is concluded that ampicillin/sulbactam is as safe and effective as clindamycin in preventing postoperative wound infection following major head and neck surgery Optimal antimicrobial prophylaxis during head and neck surgery is as yet unclear . The semisynthetic third-generation cephalosporin antibiotics would appear to have potential usefulness because of their broad antibacterial spectrum , favorable pharmacokinetic properties , and record of safety . Eighty patients were prospect ively r and omized into this placebo-controlled , double-blind study to receive either placebo , cefoperazone sodium , or cefotaxime sodium preoperatively and for 24 hours postoperatively . Infection rates were 78 % for the placebo group and 10 % for the group receiving the cephalosporin antibiotics .  Infections were polymicrobial . Anaerobic bacteria constituted 42 % of the pathogens isolated . Wound and serum antibiotic concentrations exceeded the minimal inhibitory concentration of the bacterial flora . This study establishes the necessity of antimicrobial prophylaxis for contaminated oncologic procedures of the head and neck . Our experience indicates that cefoperazone and cefotaxime are particularly useful Patients who undergo major contaminated surgery of the head and neck benefit from perioperative antibiotic prophylaxis . This study was developed to determine if 5 days of antibiotic administration would be more effective than 1 day . A multi-institutional prospect i ve r and omized double-blind study was design ed . Patients who were identified as requiring pedicled flap reconstruction were potential c and i date s for the study . Later , patients were r and omly assigned to receive cefoperazone sodium for either 24 hours or 120 hours . In each case , the drug was administered intravenously , beginning 1 to 2 hours preoperatively and continued for the prescribed period . One hundred nine patients were evaluable . Fifty-three patients were assigned to 1 day of perioperative prophylaxis .  Wound Infection developed in ten patients ( 18.9 % ) . Fifty-six patients were assigned to 5 days of perioperative antibiotic prophylaxis .  Wound infection developed in 14 ( 25 % ) of these patients ( P > .05 ) . These data suggest that no beneficial effect from administration of antibiotics for longer than 24 hours postoperatively can be achieved in patients who undergo myocutaneous flap reconstruction This study aims to give a better underst and ing of the prevalence , patterns , and determinants of postoperative complications , to evaluate the Clavien-Dindo classification of surgical complications , and to set out a protocol to improve postoperative recovery . Over a period of 27 months we studied 192 patients who had had major head and neck operations with free flaps .  Data on complications were gathered prospect ively along with patients ' details , comorbidities , factors indicative of the magnitude of the surgical insult , and variations in perioperative care . Complications were classified according to the Clavien-Dindo system . Outcomes analysed comprised any complication , major complications ( Clavien-Dindo III and above ) , wound complications , and pulmonary complications . A total of  
    Output:
    
Less than or equal to 24 hours of antibiotic prophylaxis in head and neck clean-contaminated free-flap is likely sufficient but a strong conclusion remains elusive .
Clindamycin prophylaxis increases the risk of recipient surgical site infection .