An outbreak due to multiresistant Acinetobacter baumannii in a burn unit: risk factors for acquisition and management.

OBJECTIVES: To describe the investigation and management of an outbreak due to multiresistant Acinetobacter baumannii and to determine risk factors for acquisition of the organism. SETTING: A 14-bed regional burn unit in a Canadian tertiary-care teaching hospital. DESIGN: Case-control study with multivariate analysis of potential risk factors using logistic regression analysis. Surveillance cultures were obtained from the hospital environment, from noninfected patients, and from healthcare providers. RESULTS: A total of 31 (13%) of 247 patients with acute burn injuries acquired multiresistant A. baumannii between December 1998 and March 2000; 18 (58%) of the patients were infected. The organism was recovered from the hospital environment and the hands of healthcare providers. Significant risk factors for acquisition of multiresistant A. baumannii were receipt of blood products (odds ratio [OR], 10.8; 95% confidence interval [CI95], 3.4 to 34.4; P < .001); procedures performed in the hydrotherapy room (OR, 4.1; CI95, 1.3 to 13.1; P = .02); and increased duration of mechanical ventilation (OR, 1.1 per day; CI95, 1.0 to 1.1; P= .02). INTERVENTIONS: Improved compliance with hand hygiene, strict patient isolation, meticulous environmental cleaning, and temporary closure of the unit to new admissions. CONCLUSIONS: Acquisition of multiresistant A. baumannii was likely multifactorial, related to environmental contamination and contact with transiently colonized healthcare providers. Control measures addressing these potential sources of multiresistant A. baumannii were successful in terminating the outbreak. Ongoing surveillance and continued attention to hand hygiene and adequate environmental cleaning are essential to prevent recurrent outbreaks due to antibiotic-resistant bacteria in burn units.

Cost of medications in patients admitted to a burn center.

BACKGROUND: Few studies have examined the cost associated with burn patients, and those which have been conducted have generally focused on overall hospitalization costs associated with these patients. No studies to date have examined the overall drug utilization and costs of medications used in the treatment of burn patients. OBJECTIVE: To describe the pattern of drug utilization and associated costs for the treatment of patients admitted to the Ross Tilley Burn Centre at Sunnybrook and Women's College Health Sciences Centre, Toronto, Ontario, Canada. METHODS: A retrospective chart review was conducted based on the medical records of 30 adult patients (>18 years old) consecutively admitted to the burn center between 1 August 1999 and 30 September 1999. Charts were examined to determine drugs administered, doses and duration of use. Medications administered in the operating room were excluded from the analysis. Drug costs were calculated using hospital acquisition costs (1999 Canadian dollars [$Can]) and medications were categorized by pharmacological class according to the American Hospital Formulary Service. Demographic information for the patients was extracted from the burn center's database. The economic analysis was performed from the perspective of the hospital burn center. A descriptive statistical analysis was completed for all variables; the Pearson correlation coefficient was used to examine the relationship between certain variables. A sensitivity analysis was conducted to examine the impact of patient subgroups on certain variables RESULTS: Of the 28 patients included in the analysis, 19 were admitted with acute burn injuries, two with toxic epidermal necrolysis and seven for post-burn reconstructive surgery. Patients admitted for acute burns or toxic epidermal necrolysis had the highest associated drug costs. On average, patients received 13 different drugs representing four different pharmacological categories. The mean daily drug cost per patient was $Can18.39 and the mean expenditure per admission was $Can792.97. Opioid analgesics and sedatives accounted for the largest expenditure (50.9%), followed by anti-infective agents (23.4%). For patients admitted with acute burns, there was a good correlation between daily drug costs and mortality risk (r = 0.82, p < 0.001). The findings from this study group were used to extrapolate annual expenses for medications in the burn center and these were estimated to exceed $Can280 300 in 2003. CONCLUSION: The findings of this retrospective analysis serve to elucidate the patterns of drug utilization within a population of burn patients and confirm the significant impact of a burn center on an institution's drug expenditure.

Work-related burn injuries in Ontario, Canada: has anything changed in the last 10 years?

BACKGROUND: Many burn injuries occur in the workplace. Previous research from this institution 10 years ago analyzed the incidence and nature of occupation-related burns admitted to our facility. PURPOSE: To compare the current incidence and patterns of work-related burn injuries treated at our adult regional burn center (Current group) with the findings of a similar study 10 years ago (Early group). METHODS: Retrospective study of all burn center admissions between 5 December 1998 and 31 December 2000 was completed. The data from the Early and Current groups was analyzed using the Chi-square test of homogeneity. RESULTS: During the study period, 355 patients were hospitalized. After exclusions, 100 occupational burn cases were identified (28%). The mean age of patients was 39+/-12 years, 90% were male. The mean total body surface area (TBSA) burn was 11+/-13.7%. The most common mechanism of burn was electrical (32%), followed by flame (22%), scald (17%), tar (14%), contact (8%), and chemical (7%). Four patients (4%) died of their injuries. There were no significant differences between the Current group and the Early group in terms of incidence, age, gender, occupation, mechanism of burn, or mortality. CONCLUSION: In the past 10 years no change was found in the incidence or pattern of work-related burn injuries treated at this institution. This suggests that existing prevention strategies have not been effective.

The effect of silicone gel sheets on perfusion of hypertrophic burn scars.

The mechanism of action of topical silicone gel sheets on hypertrophic scars is not well understood and their effect on the blood flow within hypertrophic scars has not been investigated. The purpose of this study was to examine whether application of silicone gel sheets produced any acute effects on blood flow in hypertrophic burn scars. Perfusion of hypertrophic scars and adjacent normal skin was measured using a laser Doppler with and without application of silicone gel sheets. Continuous measurements were made for 5 minutes before gel application, for 30 minutes during gel application and for 5 minutes following gel removal. Surface temperature of the scar was continuously monitored. An occupational therapist, blinded to the perfusion level, rated each scar using the Vancouver Scar Scale. Eighteen scars and adjacent control sites in sixteen adult burn patients (11 male, 5 female; mean age: 42 +/- 14 years) were evaluated. The mean scar age was 5.4 +/- 3.7 months. The mean Vancouver Scar Scale was 5.5 +/- 2.4. Hypertrophic scars demonstrated higher perfusion measurements at baseline compared to control areas (58.5 +/- 19.3 flux units vs 25.0 +/- 8.4 flux units; P < 0.001). Application of silicone sheeting gel did not significantly alter perfusion in either the hypertrophic scar or normal tissue from the baseline measurements. However, application of silicone gel sheeting did significantly increase the mean baseline surface temperature of the hypertrophic scar from 29 +/- 0.8 degrees C to 30.7 +/- 0.6 degrees C (P < 0.001). The mechanism of action of silicone gel sheeting probably does not involve an acute alteration in blood flow within the scar. However, surface temperature of the scar increased significantly following gel application, raising the possibility that temperature alteration is involved in the mechanism of action.

How well does the Parkland formula estimate actual fluid resuscitation volumes?

We had anecdotally observed that fluid resuscitation volumes often exceed those estimated by the Parkland Formula in adults with isolated cutaneous burns. The purpose of this study was to compare estimated and actual fluid resuscitation volumes using the Parkland Formula. We performed a retrospective study of fluid resuscitation in patients with burns > or = 15% TBSA. Patients with inhalation injury, high voltage electrical injury, delayed resuscitation, or associated trauma were excluded. We studied 31 patients (mean age 51 +/- 20 years, mean TBSA burn 27 +/- 10%). The 24 hour resuscitation volume of 13 354 +/- 7386 ml (6.7 +/- 2.8 ml/kg/%TBSA) was significantly greater than predicted (P = 0.001) and exceeded estimated volume in 84% of the patients. The mean urine output in the first 24 hrs was 1.2 +/- 0.6 ml/kg/hr. After the first 8 hours of resuscitation, the infusion rate decreased by 34% in 16 patients (DCR group), while in 15 patients the rate increased by 47% (INCR group). Both the DCR and INCR groups received significantly more fluid than predicted, (5.6 +/- 2.1 ml/kg/%TBSA and 7.7 +/- 3.1 ml/kg/%TBSA respectively). The INCR patients had significantly larger full thickness burns (14 +/- 11% vs 3 +/- 6%, P < 0.001). Our findings reveal that despite its effectiveness, the Parkland Formula underestimated the volume requirements in most adults with isolated cutaneous burns, and especially in those with large full thickness burns.

Effective hand function assessment after burn injuries.

This study compared two methods of hand function assessment, the Michigan Hand Outcomes Questionnaire (MHQ) and the Test d'Evaluation des Membres Supérieurs des Personnes Agées (TEMPA) in 20 patients discharged from a regional adult burn center (1995-1999). Spearman's rank correlation coefficient analysis was used to compare the MHQ and TEMPA scores, with P <.05 considered significant. The MHQ revealed that 68% of patients reported hand function deterioration, mainly with the nondominant hand (65%). Activities of daily living (76%) and work (59%) were the most affected. According to the MHQ, patient satisfaction correlated with work performance (r =.66, P =.002), aesthetics (r =.64, P =.003), pain (r =.59, P =.008), and activities of daily living (r =.54, P =.017). The MHQ indicated more hand function deterioration than the TEMPA. There was a significant correlation between the MHQ and TEMPA total scores (r =.68, P =.001). This study supports using the MHQ to determine which patients would benefit from the more resource-consuming TEMPA.

Hypercapnic respiratory failure and partial upper airway obstruction during high frequency oscillatory ventilation in an adult burn patient.

PURPOSE: To present a case of severe hypercapnic respiratory failure in an adult burn patient and to describe our clinical problem solving approach during support with an unconventional mode of mechanical ventilation. CLINICAL FEATURES: A 19-yr-old male with smoke inhalation and flame burns to 50% total body surface area was admitted to the Ross Tilley Burn Centre. High frequency oscillatory ventilation (HFOV) was initiated on day three for treatment of severe hypoxemia. By day four, the patient met consensus criteria for acute respiratory distress syndrome. On day nine, alveolar ventilation was severely compromised and was characterized by hypercapnea (PaCO(2) 136 mmHg) and acidosis (pH 7.10). Attempts to improve CO(2) elimination by a decrease in the HFOV oscillatory frequency and an increase in the amplitude pressure failed. An intentional orotracheal tube cuff leak was also ineffective. A 6.0-mm nasotracheal tube was inserted into the supraglottic hypopharynx to palliate presumed expiratory upper airway obstruction. After nasotracheal tube placement, an intentional cuff leak of the orotracheal tube improved ventilation (PaCO(2) 81 mmHg) and relieved the acidosis (pH 7.30). The improvement in ventilation (with normal oxygen saturation) was sustained until the patient's death from multiple organ dysfunction four days later. CONCLUSION: During HFOV in burn patients, postresuscitation edema of the supraglottic upper airway may cause expiratory upper airway obstruction. The insertion of a nasotracheal tube, combined with an intentional orotracheal cuff leak may improve alveolar ventilation during HFOV in such patients.