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Background: Adjuvant chemoradiation (CRT) is standard for head and neck squamous cell carcinoma (HNSCC) patients with positive margins or extranodal extension (ENE) following surgery. However, emerging evidence suggests the number of positive lymph nodes (LNs) is the dominant determinant of survival in non-oropharyngeal HNSCC and thus may better identify those benefiting from treatment intensification. Patients and methods: Patients from the National Cancer Database diagnosed with non-oropharyngeal HNSCC (oral cavity, larynx, hypopharynx) between 2004 and 2014 and undergoing surgical resection, neck dissection, and postoperative radiotherapy (RT) were included. Multivariable regression with first-order interaction terms was used to model the interaction between postoperative CRT and continuous number of positive LNs with respect to overall survival. Results: In total, 7144 patients met inclusion criteria. In multivariable analysis, increasing number of positive LNs was associated with both increasing mortality (P < 0.001) and increasing benefit from postoperative CRT versus RT alone (interaction P < 0.001). While there was no benefit from postoperative CRT in patients with 0-2 LN+ [hazard ratio (HR) 0.96, 95% confidence interval (CI) 0.86-1.07, P = 0.47], increased benefit was seen in those with 3-5 LN+ (HR 0.84, 95% CI 0.70-1.00, P = 0.05) and those with ≥6 LN+ (HR 0.65, 95% CI 0.51-0.82, P < 0.001) in multivariable models. By contrast, margin status and ENE did not reliably identify patients benefitting from postoperative CRT based on statistical tests of interaction. Even in patients with ENE, positive margins, or both, only those with ≥6 LN+ had improved survival with postoperative CRT. Conclusion: Increasing metastatic nodal burden was associated with increased benefit from CRT compared with RT alone, surpassing conventional high-risk factors in identifying patients benefiting from CRT. Stratification by metastatic LN number may characterize a very-high-risk patient cohort best suited for treatment intensification.

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PURPOSE: To evaluate excimer laser photorefractive keratectomy (PRK) for myopia using a repetition rate of 15 Hz instead of 10 Hz. SETTING: The Cornea and Laser Eye Institute, Teaneck, and Department of Ophthalmology, UMDNJ-New Jersey Medical School, Newark, New Jersey, USA. METHODS: Photorefractive keratectomy using a 15 Hz repetition rate was performed in 23 eyes of 14 patients by a single surgeon at 1 center. The attempted corrections ranged from -2.8 diopters (D) to -5.5 D. Preoperative and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), predictability, corneal haze, and subjective glare/halo were evaluated over 6 months. RESULTS: At 6 months, UCVA was 20/32 or better in all eyes and at least 20/20 in 14 eyes (73.7%). Two eyes (10.5%) lost 2 or more Snellen lines of BSCVA; postoperative BSCVA was at least 20/25 in 100% of eyes and 20/20 or better in 95.0%. Fifteen eyes (78.9%) were within +/-0.5 D of attempted correction, and 19 (100%) were within +/-1.0 D. Mean spherical equivalent refraction was -4.62 D preoperatively, +0.15 D at 1 month, -0.09 D at 3 months, and -0.37 D at 6 months. At 6 months, 4 eyes (21.0%) had no corneal haze and 14 (73.7%) had trace subepithelial haze. Fifteen eyes (78.9%) had no glare/halo effect at 6 months, and 4 (21.0%) had minimal glare/halo effect. CONCLUSIONS: Clinical outcomes after excimer laser PRK for myopia using an increased repetition rate of 15 Hz were good and similar to those in studies conducted with a 10 Hz repetition rate.

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OBJECTIVE: This study aimed to compare qualitative patterns of corneal topography early in the postoperative course after excimer laser photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) when used for the treatment of myopia of 6.0 to 15.0 diopters. DESIGN: The study design was a prospective, multicenter, randomized clinical trial. PARTICIPANTS: A total of 64 eyes were treated with PRK and 54 eyes were treated with LASIK. INTERVENTION: Using the Summit Apex excimer laser, patients received either PRK or LASIK using a single pass, multizone excimer laser ablation. Computer-assisted videokeratography was performed at designated postoperative examinations. MAIN OUTCOME MEASURES: Videokeratography maps at 1 and 3 months after surgery were classified using a standard classification scheme. The association of topography patterns to loss of spectacle-corrected visual acuity was tested. RESULTS: At 1 month, for the PRK (n = 60) and LASIK (n = 51) groups, respectively, 63.3% and 19.6% of eyes fell into one of the four optically irregular groups (central island, keyhole, semicircular, or irregularly irregular; P < 0.001). At 3 months, for the PRK (n = 49) and LASIK (n = 39) groups, respectively, 36.7% and 10.3% of eyes fell into one of the optically irregular groups (P = 0.004). Comparing the 1- and 3-month examination results in the PRK and LASIK groups, respectively, 19 (42%) of 45 eyes and 11 (31%) of 36 eyes had a change in topography, generally to an optically smoother pattern. The irregular groups, taken together, were associated with a greater tendency toward loss of spectacle-corrected visual acuity of two or more Snellen lines (P = 0.01). There also was greater tendency toward loss of spectacle-corrected visual acuity in the PRK group that diminished with time (P < 0.01 at 1 month, P = 0.05 at 3 months). CONCLUSIONS: After treatment for moderate-to-high myopia, LASIK topography patterns generally are more regular than are PRK patterns. This may be a result either of masking of underlying topography perturbations by the lamellar corneal flap, thus mitigating induced topography changes, or differences in surface wound healing. This study suggests that more rapid return of spectacle-corrected visual acuity found in patients treated with LASIK may be a result of more regular topography patterns early in the postoperative course.

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Patients undergoing 801 elective, clean-contaminated operations were assigned to one of the three following antibiotic regimens: 1) 1 g of cefazolin preoperatively, 2) 1 g of cefazolin preoperatively and another 1-g dose 3 hours later, and 3) 1 g of cefotetan preoperatively. These antibiotic regimens resulted in similar wound infection rates for procedures completed within 3 hours. When the procedure lasted more than 3 hours, the 6.1 per cent infection rate noted when a single dose of cefazolin was given proved significantly greater than the 1.3 per cent infection rates associated with the use of two doses of cefazolin or a single dose of the longer acting antibiotic, cefotetan (P < 0.01). Another series of 768 patients undergoing biliary and gastrointestinal tract operations were assigned to one of two antibiotic regimens: 1) a preoperative dose of 1 g of cefazolin and another 1-g dose 3 hours later if still in the operating room; 2) same as (1), plus 1-g doses every 8 hours for 24 hours. The longer period of antibiotic administration failed to improve the wound infection rate compared to the use of perioperative coverage only. These studies suggest that a single dose of preoperative antibiotic is sufficient for surgical prophylaxis when the operation is completed within 3 hours. Antibiotic coverage must extend for the duration of longer operations. A second dose of antibiotic or a single preoperative dose of an extended half-life antibiotic are equally effective. There is no value to administering antibiotics after the operation has been completed.

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BACKGROUND: The peer review process used in most hospitals is largely anecdotal, leading to criticisms about the objectivity of the methods employed. METHODS: The results of 1,500 consecutive abdominal operations performed by general surgeons working at three hospitals in a single community were reviewed. The outcome profile of each surgeon was compared statistically to the cumulative profile of the surgical community with adjustments for physiologic status of the patient, difficulty of the operation, and indications for surgery. RESULTS: A problem surgeon was thus identified whose poor results were significantly different from the rest of the surgical community and could not be explained on the basis of unfavorable patient mix or complexity of the procedures undertaken. CONCLUSIONS: Statistical comparison of a surgeon's outcome profile with those of his colleagues working in the same practice environment is suggested as an approach to the task of peer review that might prove preferable to the usual retrospective review of problem cases.

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Thirty (0.46%) patients required one or more reoperations to control bleeding after 6499 elective surgical procedures. A specific bleeding site was identified in 10 (0.15%), and bleeding was diffuse in 20 (0.31%). Bleeding occurred despite normal prothrombin and partial thromboplastin times and adequate platelet counts in all 30 cases. Diffuse bleeding was associated with the preoperative use of aspirin alone or in combination with other nonsteroidal anti-inflammatory drugs (NSAIDS) in 19 of 20 patients (95%). None of the patients with a discrete bleeding point identified at reoperation were taking these products (P < 0.001). More than one reoperation was more often required in the patients with diffuse postoperative bleeding than those with a specific site of hemorrhage. Many of these subsequent procedures were required to manage infections that developed after the first reoperation to control bleeding. Intensive care unit use, length of intensive care unit stay, total hospital stay, and hospital charges were all significantly increased when diffuse postoperative bleeding was noted. Postoperative bleeding, especially when it is diffuse rather than from a specific bleeding point, significantly prolongs hospital stay and increases costs. Bleeding is not prevented by obtaining routine screening coagulation profiles. A medication history with special attention to the recent use of aspirin and NSAIDS is advised before elective operations. Delaying surgery until the antiplatelet effects of these drugs have worn off may be advisable.

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Sprague-Dawley rats were challenged with intraperitoneal injection of 10(7) Streptococcus pneumoniae 10 days after common duct ligation (BDL) or sham celiotomy (SC). Quantitative bacterial cultures were performed on liver, spleen, lung, kidney, and heart blood samples obtained 4 hours after injection. All 13 (100%) BDL animals had positive heart blood cultures, but only 6 of 12 (50%) SC animals remained bacteremic (p < 0.05). Significantly more viable organisms were recovered from lung, liver, spleen, and kidney of BDL animals compared with SC controls. BDL impaired the host's ability to kill this encapsulated gram-positive organism. Viable bacteria remained in all organs studied, which was associated with continuing bacteremia.

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An animal wound model was used to compare the effectiveness of topical and systemic antibiotics and to examine the validity of using a combined regimen of both routes of antibiotic delivery. Gross infection rates and wound bacterial concentrations were determined after contamination with Staphylococcus aureus or Escherichia coli. Both moderate (10(8) colony-forming units [CFU]) and heavy (10(12) CFU) contamination were studied for each organism. Following moderate contamination, topical and systemic antibiotics were equally effective in reducing both wound bacterial content and infection rate, but there was no benefit from the combined use of both modes of antibiotic delivery. An additive effect of the combined regimen was noted only when the level of wound contamination was heavy.

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The medical records of all patients subjected to lower extremity amputations during a 3-year period were reviewed. It was shown that advanced age and the presence of multiple medical problems do not predispose to higher levels of limb loss. Although diabetic patients more frequently undergo amputation because of sepsis than their nondiabetic counterparts, the diabetic state was not found to be associated with a greater likelihood of above knee (AK) procedures. Prior arterial surgery was not shown to make AK amputation more likely, but it was disconcerting to note that limb salvage was not achieved in many individuals despite patent proximal inflow revascularization procedures. This initial study showed that several presumed risk factors were not predictors of amputation level. Those patients requiring AK amputations had a greater frequency of combined segment (aortoiliac and femoropopliteal) occlusive disease than those who had successful amputations at more distal levels. A follow-up study of 41 consecutive patients presenting with tissue loss due to combined segment occlusive disease was performed. Eighteen (Group I) underwent inflow procedures only, while 23 (Group II) also underwent distal revascularization. The groups were similar with respect to age, risk factors, extent of tissue loss and sepsis. At 1 year 10 (56%) Group I and only 3 (13%) Group II patients required major amputation (P = 0.01). Distal bypass, in addition to an inflow procedure, is recommended for those who present with tissue loss due to multilevel arterial occlusion.

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A time study was done to ascertain the number of hours spent in the hospital and the types of duties performed by residents enrolled in a multiple-institution, university-sponsored surgical training program. On the average, residents in the Wright State University program spent 90.1 +/- 27.1 hours in the hospital per week. Direct patient care activities required 62.7 +/- 18.8 hours (69.6%) of the average workweek. Purely educational endeavors accounted for 10.0 +/- 6.1 hours (11.1%) of the workweek. Ancillary tasks consumed an average of 8.5 +/- 8.5 hours (9.4%) of the surgical residents' time on duty per week. House officers did obtain a mean of 9.1 +/- 11.0 hours of sleep in those working hours (10.1% of the total time spent in the hospital). Although much variation existed among hospitals in the program, on-duty hours were greater in the private hospitals compared to the federal hospitals; the principal difference was the amount of time spent doing ancillary tasks (10.0 +/- 9.4 hours vs 5.6 +/- 5.6 hours; p less than 0.01). Hours worked by residents on private surgical services were longer than those of residents assigned to staff services (96.4 +/- 22.1 hours vs 86.0 +/- 29.3 hours; p less than 0.04). Again, the major difference was the greater amount of ancillary tasks performed by residents on private services (12.0 +/- 9.5 hours vs 6.2 +/- 7.0 hours; p less than 0.001). This finding could not be attributed to differences in patient census or turnover rates. Longer hours were noted on the general/thoracic surgery services compared to other surgical subspecialties (94.1 +/- 27.3 hours vs 81.5 +/- 24.8 hours; p less than 0.02). More time was spent in direct patient care on general/thoracic surgery (66.3 +/- 19.3 hours vs 54.9 +/- 15.1 hours; p less than 0.002). Despite the shorter workweek, residents on subspecialty rotations spent more time doing ancillary tasks (11.3 +/- 9.7 hours vs 7.3 +/- 7.6 hours; p less than 0.02). More than 60% of the residents' working hours in this program exceeded the arbitrary 80-hour limit, emphasizing the challenge of complying with the imposition of maximum work hours. We recommend that each program closely monitor the activities and hours of its residents to best respond to the pressures for regulation.

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The medical records of 54 patients treated for sigmoid volvulus from 1983 to 1987 were reviewed. Patient demographics were very similar to previously published results. Four patients (7.4 percent) underwent emergency resection for gangrene with a mortality of 75 percent. Of the 50 patients who presented without ischemia, 23 (46 percent) were managed by nonoperative detorsion while 3 (6 percent) detorsed spontaneously. Fourteen of these 26 patients received no further treatment. Nonoperative mortality was 0 percent. Celiotomy was performed on 36 patients. The type of operative procedure performed had no significant bearing on outcome. Fifteen patients underwent resection and anastomosis; two of these patients died (13 percent). Fifteen patients underwent resection and colostomy with two deaths (13 percent), and six had open detorsion alone with one death (17 percent). The two factors associated with adverse outcome after surgical intervention were patient age and history of previous volvulus. All five deaths occurred in patients older than 70 years presenting with a first episode of volvulus (N = 15, mortality = 33 percent). No deaths occurred among patients younger than 70 years regardless of volvulus history or among those older than 70 years who were being treated for a recurrence (P less than or equal to 0.01). Patients older than 70 years with a first episode of volvulus represent a high risk if subjected to surgical intervention. Nonoperative detorsion alone should be considered for this subgroup of patients.

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Two hundred and five consecutive explorations of the common bile duct were evaluated to assess the value of routine choledoschoscopic examination in preventing retained stones. Conventional exploration was performed in 139 instances (group 1), while routine choledochoscopy was added in 66 procedures (group 2). Preoperative temperature, leukocyte count, total bilirubin, amylase and alkaline phosphatase levels were not significantly different between the groups. Nine retained stones were demonstrated by postoperative cholangiography among the patients in group 1 as compared with three retained stones noted in those in group 2. This difference was not significant. Postoperative mortality and complication rates were unaffected by the performance of an endoscopic study of the biliary tract during ductal exploration. Choledochoscopy added an average of 36 minutes to the duration of the operative procedure (p less than 0.001). Choledochoscopy may prove helpful in selected instances, but the current data do not support its routine use during exploration of the common bile duct.

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A four-part program was implemented in order to control the rising cost of prophylactic antibiotics: limiting the number of cephalosporins on formulary; prohibiting the use of third- and most second-generation cephalosporins for prophylaxis; using a special order form to designate use as empiric, therapeutic, or prophylactic; and mandatory discontinuance of prophylactic antibiotics after 24 hours. The total cost for administration of prophylactic antibiotics was reduced from an average of $37.35 per case for the six months preceding the start of these restrictive policies to an average of $21.99 per case during the next twelve months. Class I and class II wound-infection rates were 2.0 per cent and 4.9 per cent, respectively, prior to the adoption of the new antibiotic practices. Comparable infection rates were 1.8 per cent and 2.1 per cent, respectively, after this program was initiated. The rising cost of antibiotic prophylaxis can be reduced without adversely affecting wound-infection rates.

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In a review of five Dayton, Ohio, area hospitals during a six-year period, seven patients who were treated for an acquired arteriovenous (A-V) fistula after cardiac catheterization were identified. Four patients had undergone cardiac studies in area hospitals, while three were studied elsewhere. The four A-V fistulas after 23,291 cardiac catheterization procedures in Dayton hospitals represented an incidence of 0.017% for this complication. Congestive heart failure and limb ischemia were the most frequent presenting symptoms that developed from two to ten months after catheterization. Intentional puncture of both the artery and vein of the ipsilateral groin for right- and left-sided heart studies was the probable cause of fistula formation in two cases. Five patients sustained inadvertent injury to both an artery and adjacent vein during percutaneous vascular access. Six A-V fistulas that involved femoral vessels were managed by division of the fistula with lateral repair of the artery and vein. An unusual communication between the right thyrocervical trunk and the internal jugular vein was handled by ligation of the affected vessels. Prompt surgical correction of this unusual complication of percutaneous vascular access is recommended as spontaneous closure is unlikely.

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Fifty-two patients who required reexploration through the groin incision within seven days of an arterial procedure were studied to assess the value of sartorius transposition. Twenty-four group I patients had the sartorius muscle used to cover the vascular graft at reoperation while 28 group II patients had a standard closure. The groups were similar with respect to age, initial arterial operation, incidence of diabetes, and use of antibiotics and postoperative anticoagulation. Wound complications were frequent in both groups (62.5% vs. 57.1%, respectively) but outcome of these wound problems was quite different. Graft infection and anastomotic disruption were significantly less frequent in group I patients. Because fewer infected prostheses had to be removed group I patients were less likely to require high level amputations. Sartorius transposition is an effective method of protecting vascular grafts jeopardized by the high frequency of wound problems associated with early reoperation.

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Adult male rats underwent common bile duct ligation or sham celiotomy. At intervals of 7 and 14 days postoperatively, bacteremia was induced by intravenous injection of 10(9) Escherichia coli or intraperitoneal injection of 10(6) E. coli. Serial quantitative blood cultures and quantitative whole organ cultures were obtained. One week after surgery, clearance of bacteremia was impaired in all of the animals. Clearance of intraperitoneally injected E. coli was less efficient in the duct ligation rats. Fourteen days postoperatively, clearance of bacteremia induced by intravenous or intraperitoneal injection had improved in the sham celiotomy rats but was still significantly impaired in the duct ligation rats. An increased number of viable E. coli were recovered from the lungs of duct ligation rats after intravenous administration. We found that rats with obstructive jaundice do not respond normally to a bacteremia challenge. This impairment in reticuloendothelial function can be noted as early as 1 week after common duct ligation.

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Sixty-five lower-extremity amputations were performed as a result of sepsis in diabetic patients during a 3-year period. Chronic plantar ulcer was the most frequent cause of infection. Other causes of infection included ischemic gangrene, trauma, and web space fissures. Advanced ischemia was infrequent; only 21 (32.3%) had ankle-brachial indices (ABI) less than 0.5. Eight (23.5%) deaths and 12 (35.3%) stump failures followed 34 amputations where the stump was closed, compared with no deaths and 4 (12.9%) stump failures when open amputations were done (p less than 0.02). Partial foot amputations with aggressive local debridement resulted in healing in 10 (71.4%) of 14 cases with revision or grafting. Guillotine transmalleolar amputation is advised when foot salvage is not possible, because only 1 (5.9%) of 17 such procedures could not be revised to the below-knee (B-K) level, whereas 8 (33.3%) of 24 definitive, closed B-K amputations were unsuccessful (p less than 0.02). Infections were polymicrobial, with 5.8 bacterial isolates and 2.3 anaerobes recovered per patient. Anaerobic antibiotic coverage, however, failed to alter outcome. Sepsis, often without advanced ischemia, is an important cause of limb loss in patients with diabetes. Open amputations are recommended, with foot salvage possible in many cases.

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From 1981 to 1986, antibiotic susceptibility was tested by the agar dilution method in 534 isolates of Bacteroides fragilis organisms recovered from clinical specimens. Drugs evaluated included penicillin, ampicillin, tetracycline, clindamycin, metronidazole and chloramphenicol. Based on in vitro testing, tetracycline, ampicillin and penicillin were ineffective against B. fragilis because of high rates of resistance to these agents (74 per cent tetracycline resistant, 80 per cent ampicillin resistant and 89 per cent penicillin resistant). Throughout the five years of the study, 5.1 per cent of the organisms studied were resistant to clindamycin compared with 2.1 per cent resistant to metronidazole (p less than 0.01) and 0.9 per cent resistant to chloramphenicol (p less than 0.001). More important than the relative resistance rates to the various antibiotics is the observation that this is a dynamic process that is influenced by local practices of administering antibiotics. In 1981, the first year of the survey, no clindamycin resistant B. fragilis isolates were identified; by 1986, 7.8 per cent of the strains proved resistant to this antibiotic. Similarly, no metronidazole or chloramphenicol resistant organisms were demonstrated in 1981 or 1982; thereafter, resistance to these two drugs was noted with increasing frequency each year. The emergence of B. fragilis strains that are resistant to the antibiotics in current use mandates the surveillance of the local susceptibility data to identify important trends. When increasing rates of resistance are noted to one antibiotic, alternative regimens can be used.

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