Prospective observational study to assess the need for postoperative antibiotics following surgical incision and drainage of skin and soft tissue abscess in pediatric patients

BACKGROUND

Post-operative antibiotics are often utilized for skin and soft tissue infection (SSTI) requiring surgical incision and drainage (I&D). We propose that antibiotics are unnecessary following I&D.

METHODS

Patients aged 3months to 6years with SSTI of the buttocks, groin, thigh, and/or labia requiring I&D were prospectively enrolled. The primary outcome was the proportion of patients requiring re-drainage and/or antibiotics for SSTI recurrence, within 30days. Follow-up consisted of a 30-day phone call, with optional 2-week office visit, combined with chart review for patients lost to follow-up. A one-sample binomial proportion with 95% confidence interval (CI) was used to examine non-inferiority for rate of treatment success, using previously published success rates for patients receiving antibiotics post-operatively (95.9%, with a 7% margin of equivalence).

RESULTS

A total of 92 patients were enrolled. All patients received pre-operative antibiotics. There was one treatment failure (success rate 0.989, CI 0.941-0.999). The recurrence rate was noninferior to previously-published data for patients receiving postoperative antibiotics (p<0.001). Subgroup analysis of patients who completed 30-day follow-up yielded a success rate of 0.973, CI 0.858-0.999 and evidence of non-inferiority (p=0.04).

CONCLUSIONS

Post-operative management excluding antibiotics should be considered for patients who undergo I&D for SSTI.

LEVEL OF EVIDENCE

Level II (prospective cohort study with <80% follow-up).

Same-day discharge after incision and drainage of soft-tissue abscess in diaper-age children is safe and effective

PURPOSE

Many pediatric centers admit patients following incision and drainage (I&D) of soft-tissue abscesses. The purpose of this study is to assess the safety and efficacy of the same-day discharge following I&D.

METHODS

Retrospective review was performed of children aged 3 months-4 years who underwent operative I&D of an abscess followed by same-day discharge. Patients receiving antibiotics within 2 weeks of presentation were excluded. Treatment failure was defined as readmission or repeat procedure related to the initial abscess. Statistical analysis was performed using Wilcoxon Rank-Sum and Fisher's Exact tests.

RESULTS

There were 442 procedures performed in 408 patients. Mean age was 1.8 years. Fever was noted in 25.8%. Of those who had a white blood cell (WBC) count drawn, 59.7% had leukocytosis. Mean time from procedure to discharge was 2.3 h, and 85.0% were discharged with oral antibiotics. Treatment failure occurred in four (0.9%) and ten (2.3%) patients at 14 and 30 days, respectively. Mean WBC count was higher in the 14-day treatment failure group (24.1 versus 16.3; p = 0.10). In patients with leukocytosis, there were 2 (1.4%) treatment failures compared to none in those without leukocytosis.

CONCLUSION

Same-day discharge after I&D of abscess in diaper-age children is safe and effective.

Pediatric surgery - a changing field: national trends in pediatric surgical practice

BACKGROUND

Over the last decade, our institution has experienced a relative increase in the number of mundane cases, such as appendectomy and incision and drainage of abscess, versus index (complex) cases. We sought to determine if this trend is present at the national level.

METHODS

A retrospective review of surgical case volume at 36 freestanding children's hospitals was performed between January 2004 and December 2013 using the Pediatric Health Information System (PHIS) database. Procedures were classified as "mundane" or "index", and 10 procedures of each type were selected for analysis. Results were reported as a percentage of total cases. Statistical analysis of linear trends was performed with the Mann-Kendall test.

RESULTS

Overall, index procedures had a significant downward trend (p<0.01), whereas mundane procedures had a significant upward trend (p<0.01). Individually, 5 mundane procedures had significant upward trends, and 3 had downward trends. Five index procedures had significant downward trends, and none had an upward trend.

CONCLUSION

The field of pediatric surgery is undergoing change with mundane procedures constituting an increasing proportion of the surgical caseload, while complex procedures are proportionately decreasing. These trends may be useful to inform decisions regarding future pediatric surgery workforce planning.

Robotic Surgery may Not "Make the Cut" in Pediatrics

Since the introduction of robotic surgery in children in 2001, it has been employed by select pediatric laparoscopic surgeons, but not to the degree of adult surgical specialists. It has been suggested that the technical capabilities of the robot may be ideal for complex pediatric surgical cases that require intricate dissection. However, due to the size constraints of the robot for small pediatric patients, the tight financial margins that pediatric hospitals face, and the lack of high level data displaying patient benefit when compared to conventional laparoscopic surgery, it may be some time before the robotic surgical platform is widely embraced in pediatric surgical practice.

Intra-abdominal (Type IV) sacrococcygeal teratoma presenting with buttock hemangioma

Sacrococcygeal teratoma is the most common type of extragonadal germ cell tumor in infants and young children. Sacrococcygeal teratomas can uncommonly present in an intra-abdominal fashion, with minimal clinical findings. Dermatologic lesions overlying the vertebrae or buttocks are often associated with sacrococcygeal teratoma and may be the only clue to their presence. Here, we report a case of an intra-abdominal sacrococcygeal teratoma presenting with an anatomically separate buttock hemangioma.

Perfusion induced hyperthermia for oncologic therapy with cardiac and cerebral protection

Cancer can be preferentially damaged and killed at temperatures above 41.0 degrees C. However, the heart and brain malfunction at this temperature, limiting the application of systemic hyperthermia in the treatment of metastatic cancer. We created a hyperthermic perfusion system that maximizes the temperature differential produced and extends the safe hyperthermic time. Mongrel dogs were anesthetized and mechanically ventilated. Temperature probes were placed in the rectum, bladder, peritoneal cavity, proximal aorta, pulmonary artery, and right tympanic canal. Venoarterial perfusion was instituted and the perfusate was warmed to 44 to 45 degrees C. The dogs' rectal temperature was elevated to > or = 42 degrees C for 4 hours. A small amount of venous blood was cooled to 28 to 30 degrees C and reperfused into the right atrium to maintain the pulmonary artery temperature < or = 38 degrees C. At the end of the perfusion, the dogs were decannulated, recovered, and returned to their cages for observation. Ten of 11 dogs survived the operative procedure, and no neurologic deficits were observed. The rectal temperature was successfully elevated to > or = 42 degrees C for 4 hours while maintaining the heart and brain at < or = 38 degrees C. Moderate serum biochemical changes were observed postprocedure. However, only the aspartate transaminase and alkaline phosphatase levels remained elevated above both the baseline and canine reference values by day 7. Lower abdominal and pelvic hyperthermia at 42 degrees C can be safely produced and maintained for 4 hours using an extracorporeal perfusion circuit, while protecting the heart and brain from temperature elevation.

A novel stable reproducible model of hepatic failure in canines

BACKGROUND

Stable and reproducible large animal models of hepatic failure, which allow the assessment of liver-assist devices, are not available. Our objective was to develop a physiologically stable animal model of hepatic failure on which the safety and efficacy of an extracorporeal liver-assist device can be tested. We hypothesized that a surgical model which consists of an end-to-side portocaval shunt combined with common bile duct ligation and transection would create hepatic failure with: (1) elevations in amino transferases, total bilirubin, and ammonia; (2) a decrease in the ratio of branched chain to aromatic amino acids; and (3) histologic evidence of hepatic injury.

METHODS

Eleven mongrel dogs underwent common bile duct transection and an end-to-side portocaval shunt. Aminotransferases (AST, ALT), total bilirubin, ammonia, and branched chain and aromatic amino acids were measured prior to operation (baseline) and after 9 days. A necropsy was performed on Postoperative Day 9 and liver biopsies were obtained for histology.

RESULTS

By Postoperative Day 9, AST, ALT, total bilirubin, and ammonia values were significantly elevated compared to baseline (P < 0.02). The ratio of branched chain to aromatic amino acids was significantly reduced compared to baseline (P < 0.003). There was histologic evidence of cholestasis and inflammation.

CONCLUSION

Portocaval shunt with common bile duct transection produces liver failure with elevations in aminotransferases, total bilirubin, and ammonia, a decreased branched chain to aromatic amino acid ratio, and histologic inflammation. Unlike ischemic or chemically induced models of liver failure, the dogs were hemodynamically and neurologically stable. This model can be used to test the safety and efficacy of liver-assist devices aimed at temporizing the detoxification functions of the failing liver.

Predictors of malignancy in childhood peripheral lymphadenopathy

PURPOSE

The aim of this study was to identify factors associated with malignant etiologies of childhood peripheral lymphadenopathy and to construct a model that may be used to assess the risk of malignancy.

METHODS

The medical records of 60 consecutive patients 18 years old or less who underwent peripheral lymph node biopsies were reviewed.

RESULTS

Increasing node size, number of sites of adenopathy, and age were associated with an increasing risk of malignancy (P < .05 for all variables). Graphs useful for risk determination were constructed based on these variables. Additional factors associated with malignancy included the presence of supraclavicular adenopathy (P < .01), an abnormal chest x-ray (P < .01), and fixed nodes (P < .01). Variables that were not statistically different between patients with benign and malignant adenopathy included the duration of adenopathy (P = .43), the presence of fever (P = .36), cough (P = .14), splenomegaly (P = .93), skin involvement (P = .39), tenderness (P = .49), and bilateral adenopathy (P = .39). Fluctuance was associated with benign adenopathy (P < .04).

CONCLUSIONS

The risk of malignancy increased with increasing size and number of sites of adenopathy and age. Other significant predictors of malignancy included supraclavicular location, an abnormal chest x-ray, and fixed nodes. These data may be used to supplement clinical judgment to predict the risk of malignancy.

Differential expression of Hsp27 in normal oesophagus, Barrett's metaplasia and oesophageal adenocarcinomas

The protein expression patterns of normal, metaplastic and malignant oesophageal tissues were analysed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) to identify changes associated with Barrett's metaplasia and transformation to oesophageal adenocarcinoma. Heat-shock protein 27 (Hsp27), a small heat-shock protein which is protective against cytotoxic stresses, was abundant in normal oesophagus. However, Hsp27 expression was markedly lower in Barrett's metaplasia and oesophageal adenocarcinomas. This was confirmed by immunohistochemical analysis. Hsp27 protein was most highly expressed in the upper layers of squamous epithelium and exhibited a pattern of expression that corresponded with the degree of squamous maturation. Northern and Southern analysis demonstrated Hsp27 to be regulated at the level of mRNA transcription or abundance. Normal oesophageal tissues were examined for gender differences in Hsp27 expression. Women expressed fourfold higher levels of Hsp27 mRNA, however, this difference was not appreciable in protein expression. Hsp27 protein was inducible by heat shock in Barrett's adenocarcinoma cell lines and an immortalized oesophageal epithelial cell line (HET-1A), but not by oestradiol. These results demonstrate abundant constitutive expression of the stress-response protein Hsp27 in the normal oesophagus, and suggest that low-level expression in Barrett's metaplasia may be one factor which may influence susceptibility to oesophageal adenocarcinoma development.

Can the clearance of tumor necrosis factor alpha and interleukin 6 be enhanced using an albumin dialysate hemodiafiltration system?

Patients with acute hepatic failure (AHF) have elevated levels of inflammatory cytokines such as tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6). Recently, we have shown selective hemodiafiltration with albumin dialysis, as an extracorporeal liver support device (ECLVS), to be effective in the clearance of multiple toxins that are elevated in AHF. Our objective was to evaluate whether ECLVS would be effective in the clearance of TNF-alpha and IL-6. An in vitro continuous hemodiafiltration circuit was used with single pass counter-current dialysis. A known amount of recombinant rat TNF-alpha and IL-6 was added to heparinized bovine blood and filtered across a polyalkyl sulfone hemofilter using matched filtration and dialysate flow rates. During 4 hours, the serial TNF-alpha and IL-6 concentrations were measured in the circulating blood, and the content of each cytokine was calculated using mass balance. For each cytokine, clearance was determined for two dialysate groups at constant temperature and pH (group 1: dialysate = 0.9 normal saline, n = 5; group 2: dialysate = albumin 2 gm/dl, n = 5). Analysis of data was performed using ANOVA and Student's t-test. There was improved clearance of TNF-alpha and IL-6 when albumin was used in the dialysate (81+/-0.09% of the initial TNF-alpha and 77+/-0.04% of the IL-6 quantities) compared with when 0.9 normal saline was used as the dialysate (58+/-0.14% of the initial TNF-alpha and 56+/-0.18% of the IL-6 quantities); p < 0.03. An ECLVS utilizing hemodiafiltration with albumin dialysis is more effective than conventional hemofiltration in the clearance of TNF-alpha and IL-6 and, therefore, may benefit patients with acute hepatic failure.

Use of extracorporeal life support for adult patients with respiratory failure and sepsis

Traditionally, adult sepsis has been considered a contraindication to extracorporeal life support (ECLS). The objective of this study was to review the authors' institutional experience with a subgroup of adult patients requiring ECLS for severe respiratory failure and sepsis. Hospital records from 100 consecutive adult patients with respiratory failure placed on ECLS between 1990 and 1996 were retrospectively reviewed. Patients with sepsis as a primary indication were identified, and blood culture data reviewed. Data were analyzed with t tests and chi-square and are presented as mean +/- standard deviation. Multiple logistic regression determined the impact of sepsis and positive blood cultures (PBCs) on survival. Fourteen patients required ECLS for sepsis; 36 had PBCs during hospitalization (15 before or during ECLS). Septic patients had lower pre-ECLS PaO2/FIO2 ratios (septic: 53 +/- 14 mmHg, nonseptic: 70 +/- 68 mmHg, p = 0.04). Patients with PBCs before or during ECLS were younger (PBC: 29 +/- 6 years, no PBC: 35 +/- 13 years, p = 0.003), remained on ECLS longer (PBC: 485 +/- 336 hours, no PBC: 232 +/- 212 hours, p = 0.01), and were more frequently cannulated within 12 hours (PBC: 15/15, no PBC 60/85 p = 0.02). Neither group differed in organ dysfunction (incidence or type), frequency of respiratory recovery, or survival. Neither sepsis nor positive blood cultures were independently predictive of mortality. Sepsis and positive blood cultures do not adversely affect outcome in adult patients with respiratory failure requiring ECLS.

Fas/APO-1 (CD95) is not translocated to the cell membrane in esophageal adenocarcinoma

This study describes Fas (CD95) expression in Barrett's esophagus, adenocarcinomas of the esophagus, and three esophageal adenocarcinoma cell lines. Immunohistochemical analysis of Barrett's esophagus demonstrated cell surface expression of Fas protein. In contrast, 30.5% of esophageal adenocarcinomas examined by immunohistochemical analysis demonstrated faint cytoplasmic staining, and 69.5% were negative for Fas. Similar levels of Fas mRNA were identified in tumors compared to mRNA levels in esophageal squamous mucosa or Barrett's esophagus. An approximately Mr 48,000 Fas protein was identified by Western blot analysis in tumors that were negative for Fas expression by immunohistochemical analysis. The esophageal adenocarcinoma cell line Seg-1 was negative for Fas expression by immunohistochemical analysis, but Western blot analysis demonstrated abundant, appropriately sized Fas protein. In agreement with the immunohistochemical analysis, flow cytometry of Seg-1 showed minimal amounts of Fas on the cell surface, which correlated with resistance to Fas-mediated apoptosis. No mutations in the Seg-1 Fas coding sequence or exon 1 were identified by sequence analysis. This was confirmed by transient transfection of COS cells with expression vectors generated from the Seg-1 Fas cDNA, which resulted in cell surface expression of the Fas protein. Stable transfection of Seg-1 with a Fas expression vector did not result in efficient Fas expression on the cell surface. Seg-1 cells, transiently transfected with a Fas-FLAG expression vector and examined for protein expression using confocal microscopy and an anti-FLAG antibody, showed that the Fas-FLAG protein was not present on the cell surface but was present in the cytoplasm. Taken together, these results indicate that expression of Fas on the cell surface by esophageal adenocarcinoma is reduced. In an esophageal adenocarcinoma cell line, wild-type Fas protein is retained in the cytoplasm, and this correlates with resistance to Fas-mediated apoptosis. The retention of wild-type Fas protein within the cytoplasm may represent a mechanism by which malignant cells evade Fas-mediated apoptosis.