***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: Free radicals have been implicated in the pathogenesis of neonatal sepsis and its complications . This study was conducted to determine the changes in the clinical status and the serum levels of lipid peroxidation products [ malondialdehyde ( MDA ) and 4-hydroxylalkenals ( 4-HDA ) ] in 10 septic newborns treated with the antioxidant melatonin given within the first 12 h after diagnosis . Ten other septic newborns in a comparable state were used as “ septic ” controls , while 10 healthy newborns served as normal controls . A total of 20 mg melatonin was administered orally in two doses of 10 mg each , with a 1-h interval . One blood sample was collected before melatonin administration and two additional blood sample s ( at 1 and 4 h ) were collected after melatonin administration to assess serum levels of lipid peroxidation products . Serum MDA + 4-HDA concentrations in newborns with sepsis were significantly higher than those in healthy infants without sepsis ; in contrast , in septic newborns treated with melatonin there was a significant reduction ( p < 0.05 ) of MDA + 4-HDA to the levels in the normal controls at both 1 and 4 h ( p < 0.05 ) . Melatonin also improved the clinical outcome of the septic newborns as judged by measurement of sepsis-related serum parameters after 24 and 48 h. Three of 10 septic children who were not treated with melatonin  died within 72 h after diagnosis of sepsis ; none of the 10 septic newborns treated with melatonin died . To our knowledge , this is the first study where melatonin was given to human newborns The objective of the present study was to assess the toxicology of melatonin ( 10 mg ) , administered for 28 days to 40 volunteers r and omly assigned to groups receiving either melatonin ( N = 30 ) or placebo  ( N = 10 ) in a double-blind fashion . The following measurements were performed : polysomnography ( PSG ) , laboratory examinations , including complete blood count , urinalysis , sodium , potassium and calcium levels , total protein levels , albumin , blood glucose , triglycerides , total cholesterol , high-density lipoprotein ( HDL ) , low-density lipoprotein ( LDL ) , and very low-density lipoprotein ( VLDL ) , urea , creatinine , uric acid , glutamic-oxalacetic transaminase ( GOT ) , glutamic-pyruvate transaminase ( GPT ) , bilirubin , alkaline phosphatase , gama-glutamic transaminase ( GGT ) , T3 , T4 , TSH , LH/FSH , cortisol , and melatonin serum concentrations . In addition , the Epworth Somnolence Scale ( ESS ) and a sleep diary ( SD ) were also applied to the volunteers 1 wk before each PSG . In addition , the volunteers were asked about possible side effects ( SE ) that appeared during the treatment . The study was carried out according to the following timetable : Visit 0 , filling out the term of consent and inclusion criteria ; Visit 1 , PSG , laboratory examinations , ESS , SD ,  melatonin serum concentrations ; Visit 2 , SD ,  melatonin serum concentrations , SE ; Visit 3 ,  melatonin serum concentrations , PSG , ESS , SE ; Visit 4 , laboratory examinations , SE , melatonin serum concentrations , SD ; and Visit 5 , PSG , ESS , SE . Analysis of the PSG showed a statistically significant reduction of stage 1 of sleep in the melatonin group . No other differences between the placebo and melatonin groups were obtained . In the present study we did not observe , according to the parameters analyzed , any toxicological effect that might compromise the use of melatonin at a dose of 10 mg for the period of time utilized in this study IMPORTANCE The effect of surgeons ' disrupted sleep on patient outcomes is not clearly defined . OBJECTIVE To assess if surgeons operating the night before have more complications of elective surgery performed the next day . DESIGN , SETTING , AND PARTICIPANTS Population -based , matched , retrospective cohort study using administrative health care data bases in Ontario , Canada ( 2012 population , 13,505,900 ) . Participants were 2078 patients who underwent elective laparoscopic cholecystectomies performed by surgeons who operated the night before , matched with 4 other elective laparoscopic cholecystectomy recipients ( n = 8312 ) . EXPOSURE In total , 94,183 eligible elective laparoscopic cholecystectomies were performed between 2004 and 2011 . Of these surgeries , there were 2078 procedures in which 331 different surgeons across 102 community hospitals had operated between midnight and 7 am the night before . Each " at-risk " surgery was r and omly matched with 4 other elective laparoscopic cholecystectomies ( n = 8312 ) performed by the same surgeon , who had no evidence of having operated the night before . MAIN OUTCOMES AND MEASURES The primary outcome was conversion from a laparoscopic cholecystectomy to open cholecystectomy . Secondary outcomes included evidence of iatrogenic injuries or death . Risks were quantified using generalized estimating equations . RESULTS No significant association was found in conversion rates to open operations between surgeons when they operated the night before compared with when they did not operate the previous night ( 46/2031 [ 2.2 % ] vs 157/8124 [ 1.9 % ] ; adjusted odds ratio [ OR ] , 1.18 ; 95 % CI , 0.85 - 1.64 ) . There was no association between operating the night before vs not operating the night before , and risk of iatrogenic injuries ( 14/2031 [ 0.7 % ] vs 72/8124 [ 0.9 % ] ; adjusted OR , 0.77 ; 95 % CI , 0.43 - 1.37 ) or death ( ≤5/2031 [ ≤0.2 % ] vs 7/8124 [ 0.1 % ] ) . CONCLUSIONS AND RELEVANCE No significant association was found between operating the night before and not operating the previous night for conversion to open cholecystectomy , risk of iatrogenic complications , or death for elective daytime cholecystectomy . These findings do not support safety concerns related to surgeons operating the night before performing elective surgery Melatonin has been reported to reduce preoperative anxiety . We performed this study to compare preoperative anxiety in elderly patients receiving melatonin ( M ) or placebo ( P ) .  Anxiety was measured in patients aged > 65 yr by a numerical rating scale ( range , 0–10 ) . Each patient was r and omized to receive M 10 mg or P orally : 71 patients were in group P and 67 in group M. The median ( quartiles ) anxiety level was 5 ( 2–8 ) before and 3 ( 1–7 ) 90 min after premedication in group M and 5 ( 3–6 ) and 3 ( 1–5 ) in group P , respectively . M and P reduce anxiety in elderly patients to a similar degree Perioperative myocardial ischaemia is a predictor of postoperative cardiac morbidity ( PCM ) . Epidural anaesthesia and adequate perioperative analgesia have been shown to improve myocardial oxygen dynamics due to interruption of pain and sympathetic pathways . The aim of the present study was to compare the incidence of ischaemia after either general anaesthesia followed by parenteral analgesia with morphine or combined epidural/general anaesthesia followed by analgesia with epidural morphine . In a prospect i ve observer-blinded analysis of the occurrence of ischaemia , 55 patients ( epidural = 29/ parenteral = 26 ) scheduled for elective surgery with defined risks for ischaemic cardiac disease were entered and followed for 24 hr after surgery with two-lead continuous Hotter monitoring . Groups were similar with respect to age , weight , modified Goldman ( Detsky ) risk classification and the use of cardiac medications . Fewer patients receiving the epidural anaesthesia/ analgesia had ischaemic episodes ( 17.2 vs 50.0 % , P = 0.01 ) , and tachyarrhythmias ( 20.7 vs 50.0 % , P < 0.05 ) . Epidural patients had a four-fold reduction of the relative risk for either event ( P < 0.001 ) . All ischaemic events were asymptomatic and unrecognized ( silent ) . All major morbid events ( n = 5 ) ( MI , congestive heart failure and death ) occurred in patients who had perioperative episodes of ischaemia . There were three distinct peaks in onset of ischaemia , at 1–4 hr , 9–12 hr and 22–24 hr postoperatively . One third of postoperative ischaemic events occurred within the first four hours after operation and lasted from 1 to 31 min . Forty-two percent of ischaemic episodes were associated with a heart rate > 100 bpm , or an increase of 20 % over the baseline heart rate . We conclude that epidural anaesthesia/analgesia reduces but does not eliminate the risk of myocardial ischaemia and tachyarrhythmia . We were unable to determine any associated reduction in the risk of PCM.RésuméL’ischémie myocardique périopératoire a une bonne valeur pronostique sur la morbidité cardiaque postopératoire ( MCP ) . II a été démontré que l’anesthésie et l’analgésie post-opératoire épidurales favorisaient l’oxygénation myocardique par interruption des voies de conductions algiques et sympathiques . L’objectif de la présente étude est de comparer l’incidence de l’ischémie après l’anesthésie générale suivie d’analgésie parentérale à la morphine à l’association anesthésie générale-épidurale suivie d’analgésie à la morphine épidurale . Sont inclus dans cette étude prospect i ve , à l’insu de l’observateur , 55 patients ( 29 dans le group épidural , 26 dans le groupe parentéral ) programmés pour une chirurgie réglée et présentant des risques définis de maladie cardiaque ischémique . Les patients sont monitorés continuellement pendant 24 heures après la chirurgie avec un Hotter à deux dérivations . Il n’y a pas de différence entre les deux groupes pour l’âge , le poids , l’échelle de risque de Goldman ( Detsky ) et la médication cardiaque . Moins de patients du groupe anesthésie générale-épidurale souffrent d’épisodes ischémiques ( 17,2 vs 50 % , P = 0,01 ) , et de tachyarythmies ( 20,7 vs 50 % , P < 0,05 ) . Les patients du groupe épidural courent un risque quatre fois moins élevé de souffrir de l’une ou de l’autre complication ( P < 0,001 ) . Tous les épisodes ischémiques ont été asymptomatiques et sont passés inaperçus . Toutes les complications ( n = 5 ) ( infa rct us du myocarde , défaillance cardiaque et décès ) sont survenus chez des patients qui avaient présenté de l’ischémie périopératoire . On a identifié trois pointes d’incidence ischémiques postopératoires : à 1–4 hres , 9–12 hres et 22–24 hres . Un tiers des épisodes ischemiques est survenu en-deçà de quatre heures après l’opération et a duré de 1 à 31 min . Quarante-deux pourcent de ces épisodes étaient associés à une fréquence de plus de cent b · min−1 ou à une augmentation de 20 % du niveau de base . Nous concluons que l’anesthésie / analgésie épidurale diminue mais n’élimine pas le risque d’ischémie cardiaque et de tachyarythmies . Nous n’avons pas démontré une réduction associée de la MCP STUDY OBJECTIVE To determine the significance of pain and other symptoms on the recovery process after ambulatory surgery , by surveying pain , analgesic use , and related aspects of recovery in the first 48 hours after discharge from an ambulatory surgery unit . DESIGN Prospect i ve , observational , surveillance survey . PATIENTS A total of 175 patients were studied , 25 in each of 6 surgical groups including knee arthroscopy , hernia repair , pelvic laparoscopy , transvaginal surgery , surgery for breast disease , and plastic surgery . INTERVENTIONS Patients were treated in a manner considered normal or " usual " for the surgeon and the institution . MEASUREMENTS Pain scores ( 0 to 10 ) , analgesic use , symptom frequency , symptom distress scores , activity level ( % of normal ) , and satisfaction scores were obtained by telephone interview 24 and 48 hours after discharge . Group means ( + /-SE ) , proportions and correlations between predictor variables were determined in relevant groups . MAIN RESULTS The response rate to postoperative telephone calls was 89 % at 24 hours , and 82 % at 48 hours . At 24 hours , maximum pain was > 3/10 in 60 % , or > 7/1 
    Output:
    
Conclusions : Melatonin intervention has no significant influence on well-being , sleepiness , sleep quality , pain intensity after 1 and 3 hours , headache , depression , and dizziness for laparoscopic cholecystectomy