Skin and soft tissue infections in hospitalised patients with diabetes: culture isolates and risk factors associated with mortality, length of stay and cost.

AIMS/HYPOTHESIS: Skin and soft tissue infections (SSTIs) cause substantial morbidity in persons with diabetes. There are few data on pathogens or risk factors associated with important outcomes in diabetic patients hospitalised with SSTIs. METHODS: Using a clinical research database from CareFusion, we identified 3,030 hospitalised diabetic patients with positive culture isolates and a diagnosis of SSTI in 97 US hospitals between 2003 and 2007. We classified the culture isolates and analysed their association with the anatomic location of infection, mortality, length of stay and hospital costs. RESULTS: The only culture isolate with a significantly increased prevalence was methicillin-resistant Staphylococcus aureus (MRSA); prevalence for infection of the foot was increased from 11.6 to 21.9% (p < 0.0001) and for non-foot locations from 14.0% to 24.6% (p = 0.006). Patients with non-foot (vs foot) infections were more severely ill at presentation and had higher mortality rates (2.2% vs 1.0%, p < 0.05). Significant independent risk factors associated with higher mortality rates included having a polymicrobial culture with Pseudomonas aeruginosa (OR 3.1), a monomicrobial culture with other gram-negatives (OR 8.9), greater illness severity (OR 1.9) and being transferred from another hospital (OR 5.1). These factors and need for major surgery were also independently associated with longer length of stay and higher costs. CONCLUSIONS/INTERPRETATION: Among diabetic patients hospitalised with SSTI from 2003 to 2007, only MRSA increased in prevalence. Patients with non-foot (vs foot) infections were more severely ill. Independent risk factors for increased mortality rates, length of stay and costs included more severe illness, transfer from another hospital and wound cultures with Pseudomonas or other gram-negatives.

Decision analysis: balancing quality and cost.

Healthcare reform is a topic consuming the time and energy of many healthcare professionals, administrators, and politicians. One goal of reform is to improve value--better quality health care for less cost. Unfortunately, much of the current debate proceeds without clear definitions of quality or cost. To have profitable discussion, we must have precise definitions. With these definitions in hand, the technique of decision analysis provides a unique opportunity to evaluate quality and costs of healthcare decisions simultaneously. We believe it is imperative for physicians to become familiar with this important and powerful tool.

Management of penetrating colon trauma: a cost-utility analysis.

BACKGROUND: Management of penetrating colon injuries in the presence of multiple associated risk factors is controversial. Issues not considered in previous management strategies are patient perception of quality of life with a colostomy and the true cost of each therapeutic option, which includes colostomy supplies and costs of colostomy takedown. To evaluate these issues, we performed a cost-utility analysis. METHODS: We constructed a decision tree with 3 options: primary repair, resection and anastomosis, and colostomy. Chance and decision nodes on each decision branch represent injury severity, complications, colostomy takedown, and death. Chance node frequencies and utility assignments were taken from published data. We obtained actual costs for all components of perioperative care. The outcomes reported are cost and quality of life. RESULTS: Colostomy has the least quality of life and the greatest cost. Primary repair and resection each dominate colostomy in the baseline analysis. No variable significantly altered these conclusions in sensitivity analyses. CONCLUSIONS: Simple suture or resection and anastomosis at the time of initial exploration is the dominant management method for penetrating colon trauma. It also demonstrates the trade-off between cost and life expectancy of the 3 management options.

Abdominal computed tomography scan as a screening tool in blunt trauma.

BACKGROUND: One of the most difficult problems in blunt trauma is evaluation for potential intraabdominal injury. Admission for serial abdominal exams remains the standard of care after intraabdominal injury has been initially excluded. We hypothesized a normal abdominal computed tomography (CT) scan in a subgroup of minimally injured patients would obviate admission for serial abdominal examinations, allowing safe discharge from the emergency department (ED). METHODS: We reviewed our blunt trauma experience with patients admitted solely for serial abdominal examinations after a normal CT. Patients were identified from the trauma registry at a Level 1 trauma center from July 1991 through June 1995. Patients with abnormal CTs, extra-abdominal injuries necessitating admission, hemodynamic abnormalities, a Glasgow Coma Scale less than 13, or injury severity scores (ISSs) greater than 15 were excluded. Records of 238 patients remained; we reviewed them to determine the presence of missed abdominal injury. RESULTS: None of the 238 patients had a missed abdominal injury. Average ISS of these patients was 3.2 (range, 0 to 10). Discharging these patients from the ED would result in a yearly cost savings of $32,874 to our medical system. CONCLUSIONS: Abdominal CT scan is a safe and cost-effective screening tool in patients with blunt trauma. A normal CT scan in minimally injured patients allows safe discharge from the ED.

Cervical esophageal trauma. Incidence and cause of esophageal fistulas.

Esophageal fistulas occurred in 4 (9%) of 46 penetrating esophageal wounds. All four patients with fistulas were victims of gunshot wounds, presented in shock, and underwent an urgent tracheostomy in the emergency department. Shock and urgent tracheostomy were significantly associated with fistula formation. Whether single-layer closures are adequate for esophageal wounds remains unanswered. Our data showed no disadvantage to single-layer closure, since seven of eight were successful. This compares with a success rate for multilayer closures of 32 of 35. Fifty percent of the esophageal fistulas were asymptomatic and were discovered on routine postoperative contrast study. All fistulas closed with nonoperative management. Management recommendations included nonoperative means to establish an airway, meticulous débridement, two-layer closure of the wound, closed-suction drainage, and postoperative esophagography before drain removal.

Blunt thoracic aortic trauma. A cost-utility approach for injury detection.

OBJECTIVE: To evaluate the influences of patient preference and treatment costs on the diagnostic approach to blunt aortic trauma. METHODS: Decision and cost-utility analysis. DATA SOURCES: A MEDLINE search of all literature dealing with the diagnosis and management of blunt aortic injury was used to establish assumptions and assign baseline probability estimates. Utility assignments were made from published data and our own assignments. We obtained institution-specific cost data. STUDY SELECTION: Only randomized, prospective trials that used aortography as the gold standard test were used to assign baseline accuracy of transesophageal echocardiography and dynamic chest computed tomography. Other baseline estimates were taken from class II and class III published data. DATA SYNTHESIS: A decision tree compared 4 diagnostic approaches for blunt chest trauma after an initial normal chest radiograph: observation with follow-up chest radiography, aortography, transesophageal echocardiography, and dynamic chest computed tomography. Utility (a quality-of-life measure) was assigned to ultimate health states to incorporate patient preference. Chest radiography and aortography had similar utility. Aortography gained 1 quality-adjusted life year for minimal cost. Transesophageal echocardiography and dynamic chest computed tomography lose quality-adjusted life-years at increased cost. No variable changed the relative cost-utility of the screening methods in 2-way sensitivity analyses. CONCLUSIONS: Aortography gains additional quality life at minimal cost when used as a screening method for all patients with blunt chest trauma regardless of the results of the initial chest radiograph. With a normal initial chest radiograph, transesophageal echocardiography and dynamic chest computed tomography are associated with increased cost and loss of quality-adjusted life.

The necessity and efficiency of wound surveillance after discharge.

A surgical wound surveillance program followed up 16,453 consecutive patients from 1983 through 1988. Patients were followed up for 30 days after operation, and 516 (35%) of the surgical wound infections first became manifest after discharge. In-hospital surveillance alone would have estimated the surgical wound infection rate to be 5.8% when the true rate was 8.9%. Infections that occurred after discharge were more likely in clean operations, in shorter operations, in obese patients, and in nonalcoholic patients. The probability that infections would begin after discharge was inversely associated with the duration of postoperative stay in the hospital. Postdischarge follow-up of patients who previously have undergone surgery is necessary to avoid underestimated of the infection rates and biases related to known risk factors. The most efficient time to survey patients appears to be at 21 days after the operation, at which time 90% of surgical wound infections have occurred.

Usefulness of preoperative laboratory assessment of patients undergoing elective herniorrhaphy.

Preoperative laboratory utilization was evaluated in a retrospective review of 169 adults undergoing elective inguinal herniorrhaphy at a county/university hospital and at a private/community hospital. Tests monitored included a complete blood cell count, urinalysis, serum electrolytes, chest roentgenography, and electrocardiography. Abnormal results and results that altered the patients' treatment were sought. Two groups of patients were evaluated. Group 1 (n = 105) had no disease except for the inguinal hernia; group 2 (n = 64) had evidence of another disease process. Preoperative evaluation of patients in group 1 was similar at the county/university hospital and at the private/community hospital except for increased electrolyte screening at the county/university hospital among patients younger than age 40 years. No differences between hospitals were present among patients in group 2. Abnormal results not predicted by medical history or physical examination were found in 1% of patients in group 1 and 1.4% of patients in group 2. Only four patients (2%) had their treatment altered by these findings. Preoperative laboratory evaluation of these patients revealed that an abnormal test result not predicted by history and physical examination is rare. Routine preoperative laboratory testing is of little value in this patient population.

Physical examination and arteriography in patients with penetrating zone II neck wounds.

OBJECTIVE: To review the management of patients with penetrating zone II neck wounds to discern the value of physical examination and proximity arteriography for predicting arterial injury. DESIGN: A retrospective chart review of 178 patients treated for penetrating wounds to the neck. SETTING: A level I trauma facility in Dallas, Tex. PATIENTS: All patients seen from 1987 to 1991 with platysma penetration in zone II of the neck. INTERVENTION: Physical examination, arteriography, and surgical exploration were used to identify patients with arterial injuries in the neck after penetrating trauma. MAIN OUTCOME MEASURES: To identify the presence or absence of an arterial injury. RESULTS: Negative findings on physical examination ruled out an arterial injury in 99% of all patients. Patients with any sign of arterial injury had a 26% incidence of arterial injury confirmed at operation. Of 71 arteriograms in patients without signs or symptoms of arterial injury, only one had an arterial injury requiring operative intervention. CONCLUSIONS: Findings on physical examination are good predictors of arterial injury in patients with penetrating neck wounds and can exclude injury in over 99% of patients. Arteriography is a sensitive test but has a very low yield (1.4%). These findings question whether the current practice of mandatory neck exploration or proximity arteriography is necessary for patients without signs or symptoms of injury who have penetrating wounds of the neck.

Early positive end-expiratory pressure in the adult respiratory distress syndrome.

This prospective study was designed to determine the effect of positive end-expiratory pressure (PEEP) instituted early in the course of adult respiratory distress syndrome (ARDS). Seventy-nine (7%) of 1,200 patients admitted to the surgical intensive care unit were selected because of a high probability that ARDS would develop, and were randomized into two treatment groups. Of the 79 patients, 45 were immediately treated with 5 cm H2O of end-expiratory pressure (early PEEP group), and 34 received PEEP only when severe hypoxemia developed (late PEEP group). The incidence of ARDS was significantly lower in the early PEEP group than in the late PEEP group (20% vs 53%; P less than .002). Fewer pulmonary deaths occurred in this group (11% vs 29%; P = .02), and there was less pulmonary morbidity. This study supports the efficacy of early low-level PEEP in the treatment of patients for whom there is a high probability that ARDS will develop.

Assessment of proximity of a wound to major vascular structures as an indication for arteriography.

The use of angiography to evaluate penetrating extremity wounds with proximity to major vascular structures remains controversial. Arteriography in the asymptomatic patient with a penetrating extremity wound is reported to identify arterial injuries in 6% to 21% of patients; however, some injuries may have little clinical importance. This study attempted to determine the value of proximity as an indication for angiography. Five hundred seven asymptomatic patients with 534 penetrating extremity injuries underwent arteriography due to proximity to major vascular structures. Thirty-six arteriograms (6.7%) were positive. Seven patients did not undergo operative exploration, 19 patients (3.6%) had arteriograms, and ten (1.9%) had false-positive arteriograms. The remaining 498 patients had true-negative examination results. Arteriography was associated with 13 complications (2.6%). Proved vascular injury in the clinically asymptomatic patients in our series was extremely low (3.6%). These data make it difficult to justify arteriography due to proximity of injury to major vascular structures. However, it is difficult to abandon exclusion arteriography based on these retrospective data. These observations do suggest that better criteria to define proximity need to be identified.

Effect of helium and oxygen on airflow in a narrowed airway.

A mixture of 80% helium and 20% oxygen has physical properties that increase airflow and decrease resistance in the airway when used as a portion of inspired gas. This study was designed to demonstrate and quantify the effects of a helium-oxygen mixture in a normal airway and when airway resistance is increased. Thirty healthy volunteers were studied breathing room air and the helium-oxygen mixture through a normal airway and an airway that included a resistor. Pulmonary function tests, directed by a registered respiratory therapist, were performed on all subjects using a computerized spirometer. The functional vital capacity, one-second forced expiratory volume, half-second forced expiratory volume, and peak inspiratory flow rate were analyzed. There was a statistically significant increase in 1-second forced expiratory volume using a helium-oxygen mixture in a normal airway. All pulmonary function test scores statistically improved when volunteers inspired helium and oxygen through the restricted airway, demonstrating that helium and oxygen can increase airflow in the presence of an increased airway resistance. This substantiates a role for helium and oxygen in treating conditions associated with decreased airway size and increased airway resistance.

The surgical management of duodenal trauma. Precepts based on a review of 247 cases.

The lethal potential of duodenal trauma relates to the severity of the defect, associated injuries, and the adequacy and expedience of treatment. We studied 247 patients whose injuries were managed at a single institution during an 18-year period. Emphasis was placed on complications directly related to the duodenal wound and the selection of operative repair. Repairs consisted of duodenorrhaphy in 190 patients (83%) and more complex procedures in 33 (13%). Death resulted from the duodenal injury in nine patients (4%) and fistula developed in 16 (7%). Factors associated with an increase in the morbid potential of the duodenal wound were (1) missile or blunt injury, or a defect larger than 75% of the circumference; (2) injury of the first or second portion; (3) an injury-operation delay of more than 24 hours; and (4) adjacent common bile duct injury. These factors require consideration in the selection of the operative repair.

Oral contrast solution and computed tomography for blunt abdominal trauma: a randomized study.

HYPOTHESIS: Oral contrast solution (OC) is unnecessary in the acute computed tomographic (CT) evaluation of the patient with blunt abdominal trauma. DESIGN: Randomized controlled clinical trial. SETTING: Level I trauma center at a university-affiliated teaching hospital. PATIENTS: Five hundred adult patients sustaining blunt abdominal trauma and requiring urgent resuscitation and CT evaluation of the abdomen were eligible for the study. Those patients who were younger than 18 years, pregnant, or in police custody were excluded. One hundred six patients were excluded from the analysis (15 for inappropriate enrollment, 9 because a CT scan had not been performed, 1 owing to inability to accept a nasogastric tube, and 81 owing to missing or incomplete records). Three hundred ninety-four patients with an average age of 36 years, an average Revised Trauma Score of 10, and an average Glasgow Coma Scale score of 12 are included in the analysis. INTERVENTIONS: Patients were randomized via computer-generated assignment to 1 of 2 groups either receiving OC or not receiving OC (no OC) after placement of a nasogastric tube. All patients received intravenous contrast solution and then underwent helical CT scan of the abdomen and pelvis using the GE HiSpeed Advantage CT scanner (GE Medical Systems, Milwaukee, Wis). MAIN OUTCOME MEASURES: Abnormal CT results, need for laparotomy, missed gastrointestinal tract and solid organ injuries, nausea, and vomiting. RESULTS: There were 199 patients in the OC group and 195 patients in the no OC group. Vomiting occurred in 12.9% of patients and the incidence was not different between groups. One hundred five abnormal scans (50 OC and 55 no OC) were obtained and 33 patients with abnormal scans (19 OC and 14 no OC) underwent laparotomy. There was 1 nontherapeutic laparotomy in each group. There was 1 missed small-bowel injury in the OC group (sensitivity, 86%) and no missed small-bowel injuries in the no OC group (sensitivity, 100%). Six bowel injuries were identified at laparotomy in the OC group. Two of the injuries were perforations without contrast extravasation but with pneumoperitoneum in 1. Three bowel injuries were identified in the no OC group, none of which were perforations. Seven of the 9 patients with bowel injury at laparotomy had associated intra-abdominal injury. Specificity for solid organ injury was 94% in the OC group and 57.1% in the no OC group. Sensitivity for solid organ injury was 84.2% in the OC group and 88.9% in the no OC group. The average time to abdominal CT scanning after placement of a nasogastric tube was 39.02+/-18.73 minutes in the no OC group and 45.92+/-24.17 minutes in the OC group (P= .008). CONCLUSION: The addition of OC to the acute CT protocol for the evaluation of the patient with blunt abdominal trauma is unnecessary and delays time to CT scanning.

Early steroid therapy for respiratory failure.

We performed a randomized double-blind trial to determine the usefulness of early methylprednisolone therapy for patients with pulmonary failure. We selected 81 acutely ill, mechanically ventilated patients at high risk for adult respiratory distress syndrome (ARDS). Thirty-nine patients received methylprednisolone, 30 mg/kg, every six hours for 48 hours; 42 patients received mannitol placebo. All patients were given a positive end-expiratory pressure of 5 cm H2O, monitored with pulmonary artery catheters, and treated for their primary disease processes. Twenty-five steroid-treated patients (64%) and 14 placebo-treated patients (33%) developed ARDS. Early infectious complications occurred in 30 steroid-treated patients (77%) and 18 placebo-treated patients (43%). There were no significant differences in factors predisposing to ARDS, ventilatory requirements, or days of intensive care. These results do not support the use of methylprednisolone for ARDS. Steroids failed to improve pulmonary function and were associated with an increased infection rate. Intensive pulmonary and general supportive care remain the preferred therapy for ARDS.

Cimetidine vs antacid in prophylaxis for stress ulceration.

Seven-seven critically ill patients were prospectively randomized into four groups to compare antacids and various doses of cimetidine in the neutralization of gastric acid for preventing complications of stress ulcers. Gastric pH was monitored hourly, basing the efficacy of neutralization on preselected pH values for each study group. Cimetidine provided adequate neutralization in 14 (23%) of 61 patients. Gastric acid in all 16 patients treated with antacids was adequately neutralized. Stress bleeding occurred in three (5%) patients treated with cimetidine and in no patient treated with antacids. Reversible thrombocytopenia developed in six (26%) of 23 patients treated with 2,400 mg/day of cimetidine. Hourly monitoring of gastric pH is a mandatory component in the prevention of stress bleeding. Antacid is the preferred agent for gastric acid neutralization because it is more effective, safer, and less expensive.

Combined carotid-vertebral arterial trauma.

Eight patients with simultaneous penetrating trauma to the carotid and vertebral arteries among 129 carotid and 53 vertebral arterial injuries have been treated in the last 14 years. In contrast to a 10% mortality with isolated carotid or vertebral trauma, the mortality associated with this injury complex was 50%. This high mortality directly related to the overall complexity of the trauma sustained by these patients. The liberal use of arteriography to assess penetrating cervical trauma has enhanced the diagnosis of these injuries. We recommend simultaneous surgical management of the carotid and vertebral arterial injury through an extended anterior cervical approach.

Effect of interferon gamma on infection-related death in patients with severe injuries. A randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To assess the efficacy of interferon gamma in reducing infection and death in patients sustaining severe injury. DESIGN: Multicenter, randomized, double-blind, placebo-controlled trial with observation for 60 days and until discharge for patients with major infection on day 60. SETTING: Nine university-affiliated level 1 trauma centers. PATIENTS: Four hundred sixteen patients with severe injuries, assessed by Injury Severity Score and degree of contamination. INTERVENTION: Recombinant human interferon gamma, 100 micrograms, was administered subcutaneously once daily for 21 days (or until patient discharge if prior to 21 days) as an adjunct to standard antibiotic and supportive therapy. MAIN OUTCOME MEASURES: Incidence of major infection, death related to infection, and death. RESULTS: Infection rates were similar in both treatment groups; however, patients treated with interferon gamma experienced fewer deaths related to infection (seven [3%] vs 18 [9%]; P = .008) and fewer overall deaths (21 [10%] vs 30 [14%]; P = .17). While 12 early deaths (days 1 through 7) occurred in each treatment group, late death occurred in 18 placebo-treated patients and nine in interferon gamma-treated patients. The results were dominated by findings at one center, which had the highest enrollment and higher infection and death rates. Statistical analysis did not eliminate the possibility of an unidentified imbalance between arms as an explanation for the results. CONCLUSION: Further evaluation is required to determine the validity of the observed reduction in infection-related deaths in patients treated with interferon gamma.

Cost-utility analysis of contaminated appendectomy wounds.

BACKGROUND: The influence of patient preference and treatment costs has not been considered in previous analyses of wound management decisions for contaminated right lower quadrant incisions. STUDY DESIGN: We performed a decision and cost-utility analysis, conducting a MEDLINE search of the postappendectomy wound infection literature to establish assumptions and assign baseline probability estimates. Institution-specific cost data were obtained, and utility assignments were made by the authors. Studies used to assign baseline probabilities fulfilled the following criteria: perforated appendix or gangrenous appendicitis, use of perioperative antibiotics active against aerobic and anaerobic bacteria, and data stratified by wound management, operative findings, and infection rate. RESULTS: We constructed a decision tree comparing three methods of wound management for contaminated right lower quadrant incisions: primary closure, delayed primary closure, and secondary closure. Utility (a quality of life measure) was assigned to ultimate health states to incorporate patient preference. We calculated the cost-utility for each method of wound management and found that primary closure was of optimum cost-utility compared with delayed primary closure and secondary closure. To gain one quality-adjusted life year treating a population of patients with contaminated incisions, primary closure saves $22,635 over delayed primary closure and another $22,340 over secondary closure. This decision, tested by two-way sensitivity analyses, was sensitive only to high primary closure infection rates. CONCLUSIONS: Challenging traditional surgical dogma, cost-utility analysis shows that primary closure is the favored method of management for contaminated right lower quadrant incisions. This analysis is specific to right lower quadrant incisions and the conclusion is valid for all estimated primary infection rates less than 0.27.

The anterior operative approach to the cervical vertebral artery.

BACKGROUND: Vertebral arterial trauma continues to be a perplexing diagnostic and therapeutic challenge. Operative management is often required despite improved radiologic interventions for these injuries. Accounts of the operative approaches to anterior cervical vertebral artery injuries have been limited. STUDY DESIGN: We reviewed our experience with anterior cervical vertebral arterial trauma in 53 consecutive patients requiring operative management during a 14-year period. In seven patients, the vertebral arterial injury was identified at urgent surgical intervention either for an expanded cervical hematoma or active bleeding. The remaining injuries were identified by arteriographic investigation of penetrating cervical trauma. The injuries were equally distributed between the three anatomic zones of the anterior cervical vertebral artery. The general features of the operative approaches that were used to manage these injuries were the emphasis of the study. RESULTS: The anterior approaches to patients with vertical arterial trauma were effective in controlling injuries in all cases. Proximal and distal ligation of the artery adjacent to the injury site was accomplished in 95 percent of the patients. Associated major cervical injuries in 43 percent of the patients (carotid artery, eight patients; pharyngoesophageal, six patients; and neurologic, nine patients) contributed to the postoperative morbidity rate and the overall mortality rate of 10 percent. CONCLUSIONS: The surgeon approaching vertebral arterial trauma should have a clear appreciation of the deep anterior cervical anatomy to expedite the operative management and avoid unnecessary complications related to a misdirected surgical dissection. The descriptions of the operative techniques used in this clinical experience can aid the surgeon in managing patients with vertebral vascular trauma.