Single daily dosing ceftriaxone and metronidazole vs standard triple antibiotic regimen for perforated appendicitis in children: a prospective randomized trial

Introduction

Appendicitis is the most common emergency condition in children. Historically, a 3-drug regimen consisting of ampicillin, gentamicin, and clindamycin (AGC) has been used postoperatively for perforated appendicitis. A retrospective review at our institution has found single day dosing of ceftriaxone and metronidazole (CM) to be a more simple and cost-effective antibiotic strategy. Therefore, we performed a prospective, randomized trial to compare efficacy and cost-effectiveness of these 2 regimens.

Methods

After internal review board approval (IRB no. 04 12-149), children found to have perforated appendicitis at appendectomy were randomized to either once daily dosing of CM (2 total doses per day) or standard dosing of AGC (11 total doses per day). Perforation was defined as an identifiable hole in the appendix. The operative approach (laparoscopic), length of antibiotic use, and criteria for discharge were standardized for the groups. Based on our retrospective analysis using length of postoperative hospitalization as a primary end point, a sample size of 100 patients was calculated for an α of .5 and a power of 0.82.

Results

One hundred patients underwent laparoscopic appendectomy for perforated appendicitis. On presentation, there were no differences in sex distribution, days of symptoms, temperature, or leukocyte count. There was no difference in abscess rate or wound infections between groups. The CM group resulted in significantly less antibiotic charges then the AGC group.

Conclusions

Once daily dosing with the 2-drug regimen (CM) offers a more efficient, cost-effective antibiotic management in children with perforated appendicitis without compromising infection control when compared to a traditional 3-drug regimen.     

A complete course of intravenous antibiotics vs a combination of intravenous and oral antibiotics for perforated appendicitis in children: a prospective, randomized trial

Introduction

In a previous prospective randomized trial, we found a once-a-day regimen of ceftriaxone and metronidazole to be an efficient, cost-effective treatment for children with perforated appendicitis. In this study, we evaluated the safety of discharging patients to complete an oral course of antibiotics.

Methods

Children found to have perforated appendicitis at the time of laparoscopic appendectomy were enrolled in the study. Perforation was defined as a hole in the appendix or fecalith in the abdomen. Patients were randomized to antibiotic treatment with either once daily dosing of ceftriaxone and metronidazole for a minimum of 5 days (intravenous [IV] arm) or discharge to home on oral amoxicillin/clavulanate when tolerating a regular diet (IV/PO arm) to complete 7 days.

Results

One hundred two patients underwent laparoscopic appendectomy for perforated appendicitis. On presentation, there were no differences in age, weight, sex distribution, days of symptoms, maximum temperature, or leukocyte count between the 2 groups. There was no difference in the postoperative abscess rate between the two treatment groups. Discharge was possible before day 5 in 42% of the patients in the IV/PO arm.

Conclusions

When patients are able to tolerate a regular diet, completing the course of antibiotics orally decreases hospitalization with no effect on the risk of postoperative abscess formation.     

Two-surgeon technique using saline-linked electric cautery and ultrasonic surgical aspirator in living donor hepatectomy: its safety and efficacy

Background

Saline-linked electric cautery (SLC) is introduced as an effective device to reduce blood loss in liver surgery. The aim of the current study was to evaluate the safety and efficacy of a 2-surgeon technique using SLC and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) in living donor hepatectomy.

Methods

Forty-three living donor right hepatectomy cases were enrolled in this study. The first 28 cases underwent liver transection with CUSA alone (CUSA group), while additional SLC was applied in the current 15 cases (2-surgeon technique, TS group).

Results

Blood loss was significantly reduced by the 2-surgeon technique (1,115.2 ± 652.9 g in CUSA group vs 732.3 ± 363.6 g in TS group, P < .05). In the TS group, there was no bile leakage from the cut surface. The early graft function and postoperative recipient survival were not significantly different between the groups.

Conclusions

According to our single-center experience, blood loss and donor complications in living donor hepatectomies were significantly reduced using a 2-surgeon technique using CUSA and SLC, while maintaining the graft viability.     

Complications associated with postoperative antibiotic prophylaxis after breast surgery

Background

Evidence supports single-dose preoperative antibiotic (ABX) prophylaxis for breast surgery; however, limited data exist regarding the incidence and type of antibiotic complications postoperatively.

Methods

Breast/axillary surgeries between July 2004 and June 2006 were reviewed. Complications were analyzed by antibiotic group: preoperative prophylaxis, postoperative prophylaxis, and therapeutic intent. The Fisher exact test was used to compare complication rates.

Results

A total of 389 patients underwent breast/axillary surgeries during the study period. A total of 363 (93%) patients received ABX: 353 (91%) received a single preoperative dose, 91 (23%) received postoperative ABX prophylaxis, and 76 (201%) received ABX for therapeutic intent. Among patients receiving ABX, 15 (4%) had an ABX-related complication. The ABX-related complication rate was significantly higher among those receiving postoperative prophylaxis (5.5%; 5 of 91) compared with those receiving preoperative ABX alone (0%; 0 of 214) (P = .002).

Conclusions

Drug-related complications were uncommon with preoperative ABX prophylaxis. Considering the potential complications of ABX after breast surgery, the use of postoperative prophylaxis should be reexamined.     

The impact of age, vitamin D3 level, and incidental parathyroidectomy on postoperative hypocalcemia after total or near total thyroidectomy

Background

Hypocalcemia caused by transient or definitive hypoparathyroidism is the most frequent complication after thyroidectomy. We aimed to compare the impact of incidental parathyroidectomy and serum vitamin D₃ level on postoperative hypocalcemia after total thyroidectomy (TT) or near total thyroidectomy (NTT).

Patients

Two hundred consecutive patients with nontoxic multinodular goiter treated by TT and NTT were included prospectively in the present study. Group 1 (n = 49) consisted of patients with a postoperative serum calcium level ≤8 mg/dL, and group 2 (n = 151) had a postoperative serum calcium level greater than 8 mg/dL. Patients were evaluated according to age, preoperative serum 25-hydroxy vitamin D (25-OHD) levels, postoperative serum calcium levels, incidental parathyroidectomy, and the type of thyroidectomy.

Results

Patients in group 1 (n = 49) were hypocalcemic, whereas patients in group 2 (n = 151) were normocalcemic. Preoperative serum 25-OHD levels in group 1 were significantly lower than in group 2 (P < .001). The incidence of hypoparathyroidism was significantly higher following TT (13.5%) than following NTT (2.5%) (P < .05). The risk for postoperative hypocalcemia was increased 25-fold for patients older than 50 years, 28-fold for patients with a preoperative serum 25-OHD level less than 15 ng/mL, and 71-fold for patients who underwent TT. Incidental parathyroidectomy did not have an impact on postoperative hypocalcemia. The highest risk of postoperative hypocalcemia was found in the patients with all of the above variables.

Conclusions

Age, preoperative low serum 25-OHD, and TT are significantly associated with postoperative hypocalcemia. Patients with advanced age and low preoperative serum 25-OHD levels should be placed on calcium or vitamin D supplementation after TT to avoid postoperative hypocalcemia and decrease hospital stay.     

Bipolar scissors circumcision is a safe, fast, and bloodless procedure in children

Purpose

The aim of this study is to evaluate bipolar scissors circumcision by comparing it with standard freehand scalpel procedure.

Patients and Methods

Data were analyzed from a prospective, randomized study, comparing 2 different surgical techniques for pediatric circumcision: the bipolar diathermy scissors circumcision technique with those of a conventional scalpel technique. A total of 230 pediatric patients younger than 16 years (115 in each arm of the trial) who were undergoing circumcision were reviewed prospectively. Operative time, surgical bleeding, complications, and postoperative morbidity were analyzed. Differences between bipolar scissors circumcision and conventional surgery were compared.

Results

Median blood loss for bipolar circumcision was 0.2 mL (range, 0-0.8 mL) compared with 2.1 mL in the standard group (range, 0.9-4.2 mL) (P < .001). Operative time in the bipolar diathermy treated group was significantly decreased compared with conventionally treated patients (10.8 ± 1.2 vs 19.1 ± 2.6 minutes; P < .01). Early and late postoperative morbidity were significantly decreased in circumcised patients who underwent the bipolar circumcision technique as compared with those who underwent the conventional approach regardless of the postoperative edema (22 vs 10; P = .02).

Conclusions

Bipolar scissors circumcision approach is an effective and safe procedure alternative to the standard scalpel technique in pediatric circumcision with no significant morbidity.     

Comparison of late results of basic transsternal and extended transsternal thymectomies in the treatment of myasthenia gravis

Background

The influence of the technique of thymectomy on late results in the treatment of myasthenia gravis remains controversial.

Methods

Results of 60 basic transsternal thymectomies and 58 extended transsternal thymectomies were compared. Both positive results (complete remissions or improvement) and negative results (no improvement, deterioration, or death from myasthenia) were analyzed.

Results

There were no differences between both groups according to patient's characteristics and postoperative complications rate. Ectopic foci of the thymic tissue were discovered in the fat of the neck and the mediastinum in 56.9% of patients from the extended thymectomy group. The foci occurred in all areas of dissection of the neck and the mediastinum. Complete remission rates in the basic thymectomy group were 8.3%, 11.7%, 15.0%, 16.7%, 20.0%, and 21.7% after 1, 2, 3, 4, 5, and 6 years of follow-up, respectively, and 29.3%, 37.9%, 41.4%. and 46.6% after 1, 2, 3, and 4 years, respectively, in the extended thymectomy group. The differences between both groups after 1, 2, 3, and 4 years were statistically significant (p = 0.0093, p = 0.0013, p = 0.0018, and p = 0.0007, respectively). Negative results were noted in 23.3% of patients in the basic thymectomy group and in 6.9% of patients in the extended thymectomy group (p = 0.0613). No other factors had any influence on the results.

Conclusions

Late results, both positive and negative, were considerably better in the extended thymectomy group. The difference can be explained by the removal of ectopic foci of the thymic tissue from the neck and the mediastinum in these patients.     

Induction therapy with interleukin-2 receptor antagonist after intestinal transplantation is associated with reduced acute cellular rejection and improved renal function

Purpose

To determine the effectiveness of induction immunotherapy with interleukin-2 receptor antagonists (IL2RA) after intestinal transplantation (IT).

Methods

A single-center, retrospective study was undertaken of all patients undergoing IT using existing medical records and database. Immunotherapy was either triple (standard maintenance triple therapy [SMTT]) or IL2RA [induction IL2RA plus SMTTx] or OKT3 [induction antilymphocyte preparations plus SMTTx]). Data was collected for the first 175 postoperative days. Outcomes included pretransplant renal function, posttransplant serum creatinine normalized to age (nl-sCR), rejection (ACR), and survival. Standard statistical analysis was undertaken.

Results

There were no significant differences in the groups: triple (n = 10, median age 3.5 years, cGFR 106 ± 44 mL/min), IL2RA (n = 13, median age 3.2 years, cGFR 101 ± 61 mL/min), OKT3 (n = 4, median age 7.7 years, cGFR 104 ± 27 mL/min). nl-sCR was significantly (P < .01) lower in IL2RA at most postoperative weeks. IL2RA had significantly fewer rejection and infectious episodes than the other two groups. Three-year patient survival was 92% in IL2RA versus 50% triple and OKT3.

Conclusions

IL2RA immunotherapy after IT is associated with a lower incidence of renal dysfunction as compared with historical controls. Furthermore, IL2RA therapy resulted in a lower incidence of rejection and improved survival. IL2RA should be considered in select patients undergoing IT.     

A follow-up study on postoperative function after a transanal Soave 1-stage endorectal pull-through procedure for Hirschsprung's disease

Objective

The aim of the study is to appraise bowel movements in children with Hirschsprung's disease (HD) after a transanal Soave 1-stage endorectal pull-through (TAS) procedure.

Methods

From October 2000 to October 2004, 44 patients with HD underwent a TAS procedure, 35 had a Soave operation via a laparotomy, 29 underwent a Soave procedure via laparoscopy, and 39 had an Ikeda-Soper procedure; the patients were followed up from 1 to 5 years after surgery. Evaluation of the perioperative therapeutic effect and postoperative bowel movements between the 4 groups were analyzed by Kelly's score and anorectal manometry.

Results

The TAS procedure required less operative time and costs than the Soave procedure via laparotomy or laparoscopy (P < .05) and less than that of Ikeda-Soper procedure for the duration of the preoperative preparation, the duration of the surgical procedure, intraoperative blood transfusions, days of postoperative fasting, antibiotic use, and days and cost of hospitalization (P < .01). There were no differences in short-term and long-term complications between the same Soave procedures; the Soave procedure exceeded the Ikeda-Soper operation in the incidence of enterocolitis 3 months postoperatively (P < .05), but there was no difference between the TAS procedure and the Ikeda-Soper procedure. There was no difference in bowel movements 12 months postoperatively and the rectal anal inhibitory reflex, high-pressure zone length, resting anal canal pressure, and the sensation threshold 1 year postoperatively between the TAS procedure and the Ikeda-Soper procedure, but the active contractile pressure was lower after the TAS procedure than the Ikeda-Soper procedure.

Conclusions

The TAS procedure is more suitable than the Soave operation via laparotomy or laparoscopy and Ikeda-Soper procedure and is feasible in infants with short segment type and common type HD.     

Postoperative troponin T elevation as a predictor of early acute kidney injury after orthotopic liver transplantation: a preliminary retrospective study

Background

Slight alterations in cardiac enzymes are frequently observed perioperatively among liver transplant patients. The significance of these changes in the absence of ongoing acute cardiac pathology is unknown. We sought to evaluate the link between early postoperative anomalies of serum cardiac troponin T (cTnT) in the absence of an evident cardiac cause and kidney injury during the first week of hospital stay.

Methods

We retrospectively enrolled 30 patients in the study, recording several perioperative variables, particularly cTnT on intensive care unit ICU arrival as well as 6 and 12 hours later. We grouped patients with cTnT levels >0.03 ng/mL as the high-TnT group; the others were control subjects. We recorded the highest serum creatinine, aspartate aminotransferase, alanine aminotransferase, and bilirubin levels during the first week of the hospital stay. Glomerular filtration rate (GFR) was calculated according to the Cockroft-Gault formula.

Results

Ten patients composed the high-TnT group. Their perioperative variables showed higher Model for End-Stage Liver Disease (MELD) scores and significantly greater incidences of acute kidney injury, failure, and dialysis need than control patients. GFR dropped from 118 to 66 mL/min among this group versus 112 to 105 mL/min in control subjects (P = .021). Binary logistic regression analysis revealed a higher association between the high-TnT group and acute kidney injury (P = .036) than with the MELD score (P = .719).

Conclusions

Serum cTnT levels could be influenced by both preoperative and intraoperative conditions that predispose to kidney injury.     

Comparison of Postoperative Morphine Requirements in Healthy Living Liver Donors, Patients With Hepatocellular Carcinoma Undergoing Partial Hepatectomy, and Liver Transplant Recipients

Objective

To retrospectively evaluate postoperative morphine requirements in healthy living donors undergoing partial hepatectomy and patients with end-stage hepatocellular carcinoma or end-stage liver disease undergoing liver transplantation.

Patients and Methods

The study included all patients who received intravenous patient-controlled analgesia after partial hepatectomy or liver transplantation from May 2008 to February 2009. Patients were divided into 3 groups according to type of surgery: group 1, healthy living liver donors undergoing graft procurement; group 2, patients with liver cirrhosis due to chronic hepatitis B virus or hepatitis C virus infection and hepatocellular carcinoma undergoing hepatectomy; and group 3, patients with end-stage liver disease undergoing living-donor liver transplantation. Data including patient age, morphine use, and visual analog scale score on postoperative days (PODs) 1, 2, and 3 were compared between groups using 2-way analysis of variance. P < .05 was considered significant. Values are given as mean (SD).

Results

Morphine requirement was significantly lower only in group 3 on POD 1. No difference in visual analog scale score between groups was observed postoperatively.

Conclusion

Although others have reported decreased morphine requirements on PODs 1, 2, and 3, our results indicated that morphine requirements were significantly less only on POD 1.     

Laparoscopic pyloromyotomy for hypertrophic pyloric stenosis: a prospective, randomized controlled trial

Background

Several authors have reported on laparoscopic pyloromyotomy (LP) since the technique was originally described in 1990, but its benefits remain unproven. We performed a randomized controlled trial comparing LP to open circumumbilical pyloromyotomy (OP) for hypertrophic pyloric stenosis.

Methods

In a prospective study, 102 infants with pyloric stenosis were randomly assigned to either LP (n = 50) or OP (n = 52). The primary outcome measure was the incidence of postoperative vomiting; the secondary parameters were the durations of surgery and anesthesia, surgical complications, and postoperative pain. All infants were managed according to standardized procedures regarding general anesthesia, surgical technique, postoperative analgesia, and feeding regimen. Parents, carers, and assessors responsible for the postoperative evaluation were blinded for the technique used.

Results

There was no difference in the incidence of postoperative vomiting between the 2 groups. The overall incidence of complications was similar, but the durations of surgery and general anesthesia were significantly longer in the LP group than in the OP group (P = 10⁻⁴ and P = .02, respectively). There were 3 cases of incomplete pyloromyotomy after laparoscopy, requiring a repeat procedure.

Conclusions

Laparoscopic pyloromyotomy does not decrease the incidence of postoperative vomiting, has a similar complication rate compared with the open umbilical approach, but may expose patients to a risk of inadequate pyloromyotomy.     

Haemostatic squeezing and purse-string sutures: optimising surgical techniques for early excision of critical infantile haemangiomas

Background/Purpose

Surgical excision of critical infantile haemangiomas (HMs) is usually delayed until intralesional blood flow spontaneously decreases, but fibrofatty tissue and exuberant skin invariably remain even after total involution.The aim of this study was to describe 2 surgical techniques used for early excision in 50 selected cases of HM defined critical in site or size.

Methods

Among a total of 952 patients affected by HM observed from 1999 to 2005, 50 children (5.2%) were submitted to early surgical removal of the tumour (age range, 6-24 months).In group 1, a technique of lenticular incision and linear closure was used in 34 patients using an original clamp for haemostasis during excision. In group 2, a modified round-block excision and purse-string closure technique was performed in 16 patients.

Results

Only 2 patients required transfusion to replace intraoperative blood losses. Infection, delayed wound healing, and cheloids occurred in 3 patients in group 2. Satisfactory cosmetic results have been observed in most cases in both groups at a follow-up ranging from 6 months to 6 years.

Conclusions

The range of indications for early surgical removal of critical HM might be enlarged to achieve earlier the better cosmetic results. A few surgical tricks can minimize intraoperative bleeding and optimise the surgical scar.     

Supplementation of retrobulbar block with clonidine in vitreoretinal surgery: effect on postoperative pain

Study Objective

To evaluate the effect of clonidine when added to local anesthetics on duration of postoperative analgesia during retrobulbar block.

Design

Prospective, randomized controlled trial.

Setting

Operating room and Postanesthesia Care Unit of a university-affiliated hospital.

Subjects

80 ASA physical status 1, 2, and 3 patients undergoing vitreoretinal surgery with or without scleral buckling.

Interventions

Patients in the control group (n = 40) received a retrobulbar block with 4.5 mL of lidocaine-bupivacaine and 0.5 mL of saline. Clonidine group patients (n = 40) received 4.5 mL of lidocaine-bupivacaine and 0.5 μg/kg of clonidine in a 0.5 mL volume.

Measurements

The time to first analgesic request, frequency of postoperative pain, and number of postoperative analgesic requests per patient were assessed.

Main Results

37 patients in the control group (92.5%) versus 24 patients (60%) in the clonidine group reported pain postoperatively (P = 0.001), with a shorter time to first analgesic request noted in the control group (4.9 ± 3 vs 11.9 ± 5.3 hrs; P < 0.001). The median number of postoperative analgesic requests per patient during the first 24 hours was higher in the control group than the clonidine group [2 (0-3) vs. 1 (0-3); P < 0.001].

Conclusions

The addition of clonidine 0.5 μg/kg to the local anesthetics of a retrobulbar block for vitreoretinal surgery decreases the frequency of postoperative pain and prolongs the time of analgesia.     

Effect of postoperative chemotherapy on the serum alpha-fetoprotein level in hepatoblastoma

Purpose

It is generally accepted that postoperative chemotherapy does not affect the serum alpha-fetoprotein (AFP) level. The authors report on 3 patients who supposedly showed chemotherapy-related changes in their AFP levels after operation.

Methods

This study included 3 patients with hepatoblastoma (1 case of PRETEXT III and 2 cases of PRETEXT IV).

Results

One patient with PRETEXT III underwent a complete tumor resection, and the postoperative AFP level decreased until it reached the normal range. However, he consistently exhibited a transient, 2- to 3-fold increase in the AFP after each course of chemotherapy for 3 courses. The chemotherapy regimen had to be stopped because of drug-induced encephalopathy, but he has been followed up for 5 years without any evidence of recurrence, and his AFP level has also remained stable and in the normal range. Two patients with PRETEXT IV, who underwent a curative tumor resection, also showed similar chemotherapy-related changes in AFP levels. Both of these cases were observed only after the administration of routine postoperative chemotherapy instead of administering further high-dose chemotherapy. The AFP level remained stable for 17 months and 7 months after the cessation of chemotherapy in 2 cases, respectively.

Conclusions

Regarding the postoperative chemotherapy of hepatoblastoma, we have to pay close attention to both the AFP status during chemotherapy as well as the absolute AFP level.     

Postoperative sternal dehiscence in obese patients: incidence and prevention

Background

Obesity has been identified as the single most important risk factor for postoperative sternal infection in coronary bypass surgery patients. It is also a major risk factor for sternal dehiscence, with or without infection, for any type of cardiac operation. We assessed whether prophylactic measures could prevent this complication.

Methods

Two studies were conducted. In study A, 3,158 heart surgery patients were analyzed at 3 cardiac units. Obesity was defined as body mass index (BMI) more than 30. Group I (1,253 obese [39.7%]) was compared with group II (1,905 nonobese [60.3%]). Sternal closure was done at the surgeon's preference: (a) plain wires through and through the bone; (b) peristernal figure-of-eight wires; or (c) peristernal method, using stainless-steel cables. In study B, 123 obese patients were prospectively divided into 2 subgroups. Group B-1 (54 patients) underwent lateral prophylactic sternal reinforcement before placement of peristernal wires. Group B-2 (69 patients) had standard sternal closure, as in study A.

Results

In study A, group I had 81 dehiscences (6.46%); 78 also suffered deep sternal infection and mediastinitis (96%). Despite treatment, dehiscence recurred in 13, and mortality was 38.4%. In group II nonobese patients, 31 dehisced (1.6%, p = 0.000), with no mortality. In study B, group B-1 (54) had 0% dehiscence versus group B-2 (69) with 6 dehiscences (8.7%).

Conclusions

In our study, the rate of obesity is high (∼ 40%). Sternal dehiscence is real when the BMI is more than 30 (6.46%), and has high morbidity and mortality. Prophylactic sternal reinforcement seems to prevent this complication.     

Ventricular assist device as a bridge to heart transplantation in adults

Background

Because of the shortage of donor hearts, various ventricular asist devices (VAD) have been used in decompensated patients to prolong patient survival until a suitable heart becomes available. In this paper, we present our single-center report of adult patients in whom bridging was used with VAD.

Methods

We performed a retrospective review of 14 adult patients who underwent heart transplantation after insertion of a long-term VAD. The study spans from February 2006 until September 2010. The mean patient age was 44.28 ± 11.06 years. We used the Berlin Heart EXCOR VADs (n = 11; Berlin Heart AG Berlin, Germany), or the Berlin Heart Incor (n = 2), or the Abiomed AB500 (n = 1). Preimplantation status of the subjects were critical cardiogenic shock (n = 6), deterioration on inotropes (n = 3), or stable but inotrope-dependent (n = 5).

Results

Mean VAD support time was 153.71 days (range, 25-517). Major adverse events during VAD support included reexploration for bleeding (n = 3; 21.4%), neurologic events (n = 2; 14.3%), left VAD-related infection (n = 2; 14.3%), pneumonia (n = 1; 14.3%), or primary device failure (n = 1; 7.1%). One (7.1%) patient showed evidence of human leukocyte antigen sensitization. There were 2 deaths (14.3%) over a mean of 324 days follow-up after heart transplantation: One due to biventricular failure in the early postoperative period and the other, at 69 days from pneumonia. Rejection was observed in 2 patients who had International Society for Heart and Lung Transplantation grade 2R without hemodynamic deterioration. In our series, the 1-year mortality was 14.4% among heart transplantations without VAD implantation and 14.2% among the bridge-to-transplantation group.

Conclusion

We conclude that VAD implantation improved end-organ function before heart transplantation in critically ill patients.     

Proteasome gene upregulation: a possible mechanism for intestinal adaptation

Background/Purpose

The mechanisms that control intestinal adaptation remain unknown. To better understand the adaptive process, microarray technology was used to analyze gene expression in a rat model of intestinal adaptation.

Methods

Adult male Sprague-Dawley rats underwent either a massive small bowel resection (70%) with anastomosis or a sham operation with small bowel transection and reanastomosis. After 21 days, ileal mucosa RNA was extracted. Individual RNA samples (n = 5 per group) were labeled and hybridized to 10 separate RAE 230A rat GeneChips. The signal values were calculated and the 2 groups were compared using a t test with the multiple testing correction of Benjamini and Hochberg (false discovery rate of 10%). Probe sets were analyzed for overrepresented physiologic pathways using Expression Analysis Systematic Explorer (EASE).

Results

Of the 15,866 probe sets on the RAE 230A GeneChip, 5437 probe sets were unexpressed and excluded. Of the remaining 10,429 probe sets, several overrepresented pathways (EASE score <0.01 after Bonferroni correction) were identified. Further analysis revealed that 13 probe sets related to proteasome degradation (an enzyme complex implicated in the regulation of cell proliferation) were significantly upregulated in the intestinal adaptation group compared to the sham group.

Conclusions

Proteasomes may play a critical role in regulating the proliferation of intestinal mucosa during intestinal adaptation.     

Bacteriologic features of surgical site infections following breast surgery

Background

Perioperative antibiotic prophylaxis to prevent surgical site infections (SSIs) after breast surgery is common practice. Breast SSIs were investigated to determine bacterial isolates, resistance patterns, and the appropriateness of cefazolin, the authors' institution's current regimen for perioperative antibiotic prophylaxis.

Methods

A retrospective review of 53 patients with culture-positive breast SSIs between June 1997 and August 2008 identified patient characteristics, bacterial isolates, and microbial resistance patterns.

Results

Among the 53 patients with positive cultures, 42% (n = 22) had undergone mastectomy, and 34% (n = 18) had undergone lumpectomy. Sixty-three bacterial isolates were identified, with 15% of SSIs being polymicrobial. Of the isolates, 49% (n = 31) were gram-negative bacteria. There was only 1 case of methicillin-resistant Staphylococcus aureus. Eight of 63 (13%) gram-negative isolates were cefazolin resistant.

Conclusions

Gram-negative SSIs constituted half of the SSIs in this breast surgery cohort. Of all breast isolates, 17.5% were resistant to cefazolin. On the basis of these findings, antibiotic prophylaxis regimens alternative to cefazolin should be considered.