***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 
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    Input: Background : Electroconvulsive therapy ( ECT ) is one of the available and the most effective therapies for the treatment of resistant depression . Considering the crucial role of seizure duration on therapeutic response in patients treated with ECT , this study aim ed to compare the effect of ketamine and sodium thiopental anesthesia during ECT for treatment of patients with drug-resistant major depression ( DRMD ) . Material s and Methods : In a double-blind r and omized clinical trial , 160 patients with DRMD were selected consequently and were assigned r and omly into two groups including ketamine 0.8 mg/kg and sodium thiopental 1.5 mg/kg . The seizure duration , recovery time , and the side effects of anesthesia were evaluated after 1-h after anesthesia . Data of recovery time and complication collected in 2nd , 4th , 6th , and 8th ECT . Depression was assessed by Hamilton depression scale . Results : The results indicated that ketamine and sodium thiopental had a significant effect on the reduction of depression scores in patients with DRMD ( P < 0.05 ) . Complications such as a headache , nausea , pain at the injection site , short-term delirium , and long-term delirium were higher in ketamine group ( P > 0.05 ) . But ketamine was more effective in improvement of depression score and increasing systolic and diastolic blood pressure ( P < 0.05 ) . The mean of seizure duration showed a decreasing trend and was significant between two study groups ( P < 0.05 ) . Conclusion : Anesthesia induced by ketamine during ECT therapy increased blood pressure and seizure duration . Therefore , due to lower medical complication and attack rate of seizure , ketamine is an appropriate option for anesthesia with ECT in patients with DRMD BACKGROUND Patients who experience a fragility hip fracture are at high risk for perioperative delirium . The purpose of the present study was to evaluate the impact , from a hospital perspective , of perioperative delirium on the length of the hospital stay and episode-of-care costs for elderly patients who underwent surgical treatment of a fragility hip fracture . METHODS A total of 242 patients sixty-five years of age or older ( mean age , eighty-two years ; range , sixty-five to 103 years ) who underwent surgical treatment of a fragility hip fracture at a single center between January 2011 and December 2012 were evaluated . Demographic , clinical , surgical , and adverse-events data were extracted and analyzed . The  confusion assessment method ( CAM ) was used prospect ively to detect perioperative delirium . RESULTS One hundred and sixteen ( 48 % ) of the 242 patients developed perioperative delirium during their stay in the hospital . Compared with patients with no delirium , delirium was associated with a mean incremental total length of hospital stay of 7.4 days ( 95 % confidence interval [ CI ] = 3.7 to 11.2 days ; p < 0.001 ) , a mean incremental length of stay following surgery of 7.4 days ( 95 % CI = 3.8 to 11.1 days ; p < 0.001 ) , and a mean incremental episode-of-care cost ( in 2012 Canadian dollars ) of $ 8286 ( 95 % CI = $ 3690 to $ 12,881 ; p < 0.001 ) . The total incremental episode-of-care cost attributable to delirium over the study period was $ 961,131 in 2012 Canadian dollars . CONCLUSIONS Nearly 50 % of elderly patients who underwent surgery for a fragility hip fracture developed perioperative delirium , which was associated with a significant incremental in-hospital length of stay and significant incremental episode-of-care costs . These findings highlight the importance of implementing cost-effective interventions to reduce the prevalence of perioperative delirium in elderly patients with a low-energy hip fracture Spreading depolarizations are waves of mass neuronal and glial depolarization that propagate across the injured human cortex . They can occur with depression of neuronal activity as spreading depressions or isoelectric spreading depolarizations on a background of absent or minimal electroencephalogram activity . Spreading depolarizations are characterized by the loss of neuronal ion homeostasis and are believed to damage functional neurons , leading to neuronal necrosis or neurological degeneration and poor outcome . Analgesics and sedatives influence activity-dependent neuronal ion homeostasis and therefore represent potential modulators of spreading depolarizations . In this exploratory retrospective international multicentre analysis , we investigated the influence of midazolam , propofol , fentanyl , sufentanil , ketamine and morphine on the occurrence of spreading depolarizations in 115 brain-injured patients . A surface electrode strip was placed on the cortex , and continuous electrocorticographical recordings were obtained . We used multivariable binary logistic regression to quantify associations between the investigated drugs and the hours of electrocorticographical recordings with and without spreading depolarizations or clusters of spreading depolarizations . We found that administration of ketamine was associated with a reduction of spreading depolarizations and spreading depolarization clusters ( P < 0.05 ) . Midazolam anaesthesia , in contrast , was associated with an increased number of spreading depolarization clusters ( P < 0.05 ) . By using a univariate odds ratio analysis , we also found a significant association between ketamine administration and reduced occurrence of isoelectric spreading depolarizations in patients suffering from traumatic brain injury , subarachnoid haemorrhage and malignant hemispheric stroke ( P < 0.05 ) . Our findings suggest that ketamine-or another N-methyl-d-aspartate receptor antagonist-may represent a viable treatment for patients at risk for spreading depolarizations . This hypothesis will be tested in a prospect i ve study Background The rapid emergence and recovery from general anesthesia afforded by sevoflurane is associated with a high incidence of emergence agitation in children . Small doses of ketamine reduce the incidence of emergence agitation . This study compared the effects of ketamine 0.25 mg/kg and 0.5 mg/kg on emergence agitation and postoperative pain . Methods The effects of added intravenous ketamine were evaluated in 93 children , ASA I-II , 2 - 14 years old , undergoing an adenotonsillectomy .  The patients were allocated r and omly to one of three groups receiving saline ( group C ) , ketamine 0.25 mg/kg ( group K0.25 ) or ketamine 0.5 mg/kg ( group K0.5 ) . The children in each group were administered the study drugs 10 minutes before the end of surgery . The recovery characteristics , including the time to extubation , delivery time from the PACU , postoperative nausea and vomiting , agitation and pain were assessed . Results There were no significant differences in the extubation time , delivery time and postoperative nausea and vomiting between the three groups . There were significant differences in modified CHEOPS ( Children 's Hospital of Eastern Ontario Pain Scale ) between the three groups . The incidence of emergence agitation was low in the K0.25 and K0.5 groups compared to the control group . However , there was no significant difference between the K0.25 and K0.5 groups . Conclusions There was no significant difference in the incidence of emergence agitation between K0.25 and K0.5 groups . However , K0.5 group showed a lower pain score than K0.25 group STUDY OBJECTIVE To determine the effects of low-dose ketamine and propofol on cough during emergence and the recovery period when administered at emergence in children undergoing fiberoptic bronchoscopy for bronchoalveolar lavage ( FOBL ) with sevoflurane-remifentanil anesthesia . DESIGN R and omized , double-blind , placebo-controlled trial . SETTING Operating room , postoperative recovery area . PATIENTS Sixty-eight children aged 1 to 8 years old undergoing elective diagnostic FOBL . INTERVENTIONS After discontinuation of anesthetics at the end of FOBL , patients were r and omly divided into 3 groups : in group K , children were administered 0.5 mg/kg of ketamine ; in group P , 0.5 mg/kg of propofol ; and in group C , 0.1 mL/kg of normal saline . MEASUREMENTS Anesthesia time , procedure time , emergence time , and recovery time were recorded . Coughing and delirium scores were recorded as the patient fully emerged from anesthesia ( time 0 ) and 5 , 10 , 15 , and 20 minutes later . MAIN RESULTS The percentage of children with moderate or severe cough during emergence was similar in all groups . Mean delirium scores at emergence ( T0 ) were significantly lower in group K than those in group P and in group C ( P = .0001 and P = .02 ) . Mean delirium score at 5 minutes in group K ( 6 [ 5 - 10 ] ) was significantly lower than that of group C ( P = .02 ) and similar to that of group P. The recovery time of group K was significantly longer than that of group C and group P ( P = .01 and P = .03 , respectively ) . CONCLUSIONS Ketamine or propofol given at the end of sevoflurane-remifentanil general anesthesia in children undergoing FOBL did not decrease cough more than normal saline during the emergence period . Ketamine and propofol , compared to normal saline , had a beneficial effect on decreasing the incidence of emergence delirium . Ketamine lengthened recovery time BACKGROUND The EEG-Bispectral Index ( BIS ) is a processed EEG information that has been vali date d as a means to measure the hypnotic effect of anesthetic drugs . In this study we evaluated the BIS changes in induction of anesthesia with ketamine in comparison with that of thiamylal . METHODS Forty ASA class I and II adult female patients undergoing elective gynecologic surgeries were enrolled into this r and omized , prospect i ve study . No premedication was given to the patient . In each patient  EEG  was recorded continuously from the frontal electrodes using Aspect A-1050 monitor after his arrival at the operating room . Blood pressure and heart rate were also recorded throughout the surgery . After steady baseline recordings of all necessary parameters having been accomplished Group K patients ( n = 20 ) were given an induction dose of ketamine 1.5 mg/kg i.v . , whereas Group T patients ( n = 20 ) received thiamylal 5 mg/kg i.v . When loss of consciousness was ascertained , intubation was performed after administration of succinylcholine 1 mg/kg i.v . and anesthesia was maintained with isoflurane-nitrous oxide-oxygen .  Demographics , BIS values , HR , BP were analyzed and compared . RESULTS The demographics were comparable between the two groups . Both groups showed a mean value of BIS of 96 with comparable BP and HR before induction . After study drug the post-induction BIS for ketamine was 94 as against 51 for thiamylal ( P < 0.05 ) , 91 against 43 post-succinylcholine ( P < 0.05 ) , 92 against 53 post-intubation ( P < 0.05 ) and 45 against 37 five min after isoflurane .  BIS remained below 60 throughout the entire course of anesthesia and returned to above 95 on emergence in both groups . None of the patients reported awareness , recall , delirium or hallucination during anesthesia . CONCLUSIONS Ketamine-induced dissociative anesthesia produces persistently elevated BIS index which is different from thiamylal and those reported with other conventional anesthetic agents . The established range of BIS index appears not to be applicable in patients under ketamine anesthesia . Monitoring the depth of ketamine anesthesia remains to be a challenging problem Magnetic resonance imaging ( MRI ) requires long-lasting immobilization that frequently can only be provided by general anesthesia in pediatric patients .  Sevoflurane provides adequate anesthesia but many patients experience emergence agitation . Small doses of ketamine and nalbuphine provide moderate sedation but their benefits have subsided at the time of emergence . We hypothesized that delaying their administration until the end of the procedure would prevent emergence agitation without prolonging patient wake-up and discharge times from the postanesthesia care unit . We performed a double-blind study involving 90 patients ( aged 6 mo to 8 yr ) r and omly allocated to 1 of 3 groups receiving either saline ( S-group ) , ketamine ( 0.25 mg/kg ) ( K-group ) , or nalbuphine ( 0.1 mg/kg ) ( N-group ) at the end of an MRI procedure under sevoflurane anesthesia . We evaluated emergence conditions , sedation/agitation status and completion of discharge criteria at 30 min . The three groups were comparable in age , sex ratio , physical status , and associated medical disorders . Emergence conditions did not differ significantly . There were significantly more agitated children , at all times , in the S-group and more obtunded patients at early times ( 5 and 10 min ) in both K- and N-groups . All patients met discharge criteria at 30 min but significantly more children were awake and quiet in the K-group and still more in the N-group . In conclusion , small doses of ketamine or nalbuphine administered at the end of 
    Output:
    
The effect of ketamine on postoperative delirium remains unclear but its administration may offer some protection towards POCD .