510597
research-article2013
CPJXXX10.1177/0009922813510597Clinical PediatricsLane et al
Article
Treatment of Skin and Soft Tissue Infections in a Pediatric Observation Unit
Clinical Pediatrics 2014, Vol. 53(5) 439–443 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0009922813510597 cpj.sagepub.com
Roni D. Lane, MD1, David R. Sandweiss, MD1, and Howard M. Corneli, MD1
Abstract Objectives. To report the success rate of observation unit (OU) treatment of pediatric skin and soft tissue infections (SSTIs) and to see if we could identify variables at the time of initial evaluation that predicted successful OU treatment. Methods. A retrospective review of children less than 18 years of age admitted for SSTI treatment to our OU from the emergency department between January 2003 and June 2009. Results. On records review, 853 patients matched eligibility criteria; median age was 5.2 years (interquartile range = 2.5-9 years). Of the 853 patients, 597 (70.0%) met the primary outcome criteria of successful OU discharge within 26 hours. Secondary analysis revealed that 82% of the patients achieved successful discharge from the OU within 48 hours. Although some laboratory variables demonstrated statistical association with success, none achieved a combination of high sensitivity and specificity to predict OU failure. OU success rates varied by location. Dental and face infections and those of the extremities or multiple sites demonstrated OU success rates higher than 65%, while infection of the groin, buttocks, trunk, or neck had success rates between 24% (neck) and 60% (groin). In multivariate analysis, only 3 variables remained significant. Unfavorable location was most strongly associated with OU failure, followed by C-reactive protein > 4 and then by erythrocyte sedimentation rate > 20. Conclusions. Our findings suggest that successful OU treatment is possible in a large group of patients needing hospitalization for SSTIs. Consideration of infection location may assist the emergency department clinician in determining the most appropriate unit for admission. Keywords skin and soft tissue infection, observation unit, emergency department
Introduction The incidence of skin and soft tissue infections (SSTIs) has increased rapidly nationwide. In 2005, there were 14.2 million outpatient visits for SSTIs, with >95% attributable to cellulitis/abscess.1 From 1997 to 2009, the weighted proportion of pediatric SSTI hospitalizations increased from 0.46% to 1.01%.2 SSTIs are frequently encountered in the emergency department (ED). Though many children are successfully discharged to home with oral antibiotics, some will require hospitalization.3-5 Clinicians must rely on their clinical judgment when determining disposition. For children requiring hospitalization, management in an observation unit (OU) may be considered. A few studies address the treatment of pediatric SSTIs in an OU setting.6-8 Although predictors of OU success and failure in patients admitted with SSTIs have been described in the adult literature,9-11 we found no such studies in children. The objective of our study was to report the success rate
of OU treatment of pediatric SSTIs and to see if we could identify variables at the time of initial evaluation that predicted successful OU treatment. Such information could improve bed utilization, decrease patient transfers, and enhance parent, patient, and physician satisfaction.
Methods Study Design We conducted a retrospective chart review of children admitted from our ED to OU for treatment of SSTIs between January 2003 and June 2009. The study was approved by the governing institutional review board. 1
University of Utah, Salt Lake City, UT, USA
Corresponding Author: Roni D. Lane, Department of Pediatrics, Division of Emergency Medicine, PO Box 581289, Salt Lake City, UT 84158, USA. Email: [email protected]
Downloaded from cpj.sagepub.com at The University of Iowa Libraries on May 26, 2015
440
Clinical Pediatrics 53(5)
Study Setting and Population Our hospital is a 289-bed regional, tertiary care, pediatric center with an annual ED census of approximately 42 000 and an ED admission rate of approximately 23% including OU admissions. The OU, adjacent to the ED, is an 18-bed unit staffed full-time by general pediatricians or pediatric emergency medicine physicians. Patients are admitted to the OU if they are expected to meet discharge criteria within approximately 24 hours. A list of ICD-9-CM discharge diagnosis codes indicative of SSTIs was obtained from the Centers for Disease Control and Prevention. Electronic data sources within Intermountain Healthcare’s Electronic Data Warehouse were queried to identify patients who were admitted to the OU from the ED and satisfied at least one of the ICD-9-CM codes. Patients were excluded if they were >18 years of age, admitted to the OU for a different primary indication, admitted under a subspecialty service, or if there were insufficient data available. Electronic hospital records were the primary source of information. Paper charts were examined if electronic records were incomplete. All records were reviewed by 1 of 3 individuals (2 of the authors, RL and DS, and a research assistant). Data abstracted included hospital length of stay (LOS), patients’ age and sex, the location of infection, the presence of fever or abscess, prior antibiotic treatment, incision and drainage (I&D) prior to OU admission, prior history of an SSTI (with or without methicillin-resistant Staphylococcus aureus [MRSA]), history of MRSA exposure, white blood cell count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) if measured, and wound as well as blood culture results if obtained.
Outcome Measures The primary outcome was taken as successful OU discharge, defined as LOS of 26 hours or less. This time limit was chosen to reflect a 24-hour LOS target plus an allowance for the time to achieve actual discharge; a sensitivity analysis showed that the results presented here would not change significantly if a 24-hour limit were studied. Admission to the inpatient service before 26 hours was counted as OU failure. Because LOS requirements vary by institution, we also analyzed the OU discharge rate within 48 hours as a secondary outcome.
Statistical Analysis We analyzed categorical variables using Fisher’s exact test and continuous variables using nonparametric methods. In all cases, α was set at .05, and confidence intervals were calculated at the 95% level. We used
logistic regression to find adjusted odds ratios in multivariate modeling. To create binary (0 or 1) predictors for analysis, infection location was dichotomized by higher or lower success rate, and laboratory markers of inflammation were dichotomized around common clinical cutoffs (WBC > 10 000, CRP > 4 mg/L, ESR > 20 mm/h).
Results On records review, 853 patients matched eligibility criteria, of whom 394 (46%) were girls. Ages ranged from 0 through 17 years, with a median age of 5.2 years (interquartile range = 2.5-9 years); infants 4 mg/L and then by ESR > 20 mm/h (Table 3). Among the 276 patients in whom blood cultures were obtained, 8 blood cultures were positive for likely pathogens and 8 for likely contaminants. Thus, only 8 (2.9%) of the patients who had a blood culture performed or 0.9% of all patients studied had a true positive blood culture. It is not clear if these few true positives altered therapy or success.
Downloaded from cpj.sagepub.com at The University of Iowa Libraries on May 26, 2015
441
Lane et al Table 1. Patient Characteristics by Observation Unit Success or Failure. Patient Characteristic Mean age, years Female sex, no./total no. (%) History of fever, no./total no. (%) History of exposure to MRSA, no./total no. (%) Incision and drainage after admission, no./total no. (%) Mean WBC, ×1000 Mean CRP, mg/L Mean ESR, mm/h
OU Success
OU Failure
Difference Between Groups (95% CI)
P Value
6.3 264/597 (44.2) 258/597 (43.2) 28/593 (4.7) 84/594 (14.1)
5.6 130/256 (50.8) 162/256 (63.3) 22/254 (8.7) 57/255 (22.3)
0.7 (0.02, 1.34) 6.6% (−0.7%, 13.9%) 20.1% (12.9%, 27.2%) 3.9% (0.1%, 7.8%) 8.2% (2.4%, 14.0%)
.04 .08 (ns) 10 000 Need for I&D after admission Female sex
3.3 2.8 2.6 2.3 2.1 1.9 1.9 1.8 1.3
2.0, 5.2 1.7, 4.5 1.7, 3.9 1.7, 3.1 1.2, 3.4 1.1, 3.4 1.3, 2.9 1.2, 2.5 1.0, 1.7
research-article2013
CPJXXX10.1177/0009922813510597Clinical PediatricsLane et al
Article
Treatment of Skin and Soft Tissue Infections in a Pediatric Observation Unit
Clinical Pediatrics 2014, Vol. 53(5) 439–443 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0009922813510597 cpj.sagepub.com
Roni D. Lane, MD1, David R. Sandweiss, MD1, and Howard M. Corneli, MD1
Abstract Objectives. To report the success rate of observation unit (OU) treatment of pediatric skin and soft tissue infections (SSTIs) and to see if we could identify variables at the time of initial evaluation that predicted successful OU treatment. Methods. A retrospective review of children less than 18 years of age admitted for SSTI treatment to our OU from the emergency department between January 2003 and June 2009. Results. On records review, 853 patients matched eligibility criteria; median age was 5.2 years (interquartile range = 2.5-9 years). Of the 853 patients, 597 (70.0%) met the primary outcome criteria of successful OU discharge within 26 hours. Secondary analysis revealed that 82% of the patients achieved successful discharge from the OU within 48 hours. Although some laboratory variables demonstrated statistical association with success, none achieved a combination of high sensitivity and specificity to predict OU failure. OU success rates varied by location. Dental and face infections and those of the extremities or multiple sites demonstrated OU success rates higher than 65%, while infection of the groin, buttocks, trunk, or neck had success rates between 24% (neck) and 60% (groin). In multivariate analysis, only 3 variables remained significant. Unfavorable location was most strongly associated with OU failure, followed by C-reactive protein > 4 and then by erythrocyte sedimentation rate > 20. Conclusions. Our findings suggest that successful OU treatment is possible in a large group of patients needing hospitalization for SSTIs. Consideration of infection location may assist the emergency department clinician in determining the most appropriate unit for admission. Keywords skin and soft tissue infection, observation unit, emergency department
Introduction The incidence of skin and soft tissue infections (SSTIs) has increased rapidly nationwide. In 2005, there were 14.2 million outpatient visits for SSTIs, with >95% attributable to cellulitis/abscess.1 From 1997 to 2009, the weighted proportion of pediatric SSTI hospitalizations increased from 0.46% to 1.01%.2 SSTIs are frequently encountered in the emergency department (ED). Though many children are successfully discharged to home with oral antibiotics, some will require hospitalization.3-5 Clinicians must rely on their clinical judgment when determining disposition. For children requiring hospitalization, management in an observation unit (OU) may be considered. A few studies address the treatment of pediatric SSTIs in an OU setting.6-8 Although predictors of OU success and failure in patients admitted with SSTIs have been described in the adult literature,9-11 we found no such studies in children. The objective of our study was to report the success rate
of OU treatment of pediatric SSTIs and to see if we could identify variables at the time of initial evaluation that predicted successful OU treatment. Such information could improve bed utilization, decrease patient transfers, and enhance parent, patient, and physician satisfaction.
Methods Study Design We conducted a retrospective chart review of children admitted from our ED to OU for treatment of SSTIs between January 2003 and June 2009. The study was approved by the governing institutional review board. 1
University of Utah, Salt Lake City, UT, USA
Corresponding Author: Roni D. Lane, Department of Pediatrics, Division of Emergency Medicine, PO Box 581289, Salt Lake City, UT 84158, USA. Email: [email protected]
Downloaded from cpj.sagepub.com at The University of Iowa Libraries on May 26, 2015
440
Clinical Pediatrics 53(5)
Study Setting and Population Our hospital is a 289-bed regional, tertiary care, pediatric center with an annual ED census of approximately 42 000 and an ED admission rate of approximately 23% including OU admissions. The OU, adjacent to the ED, is an 18-bed unit staffed full-time by general pediatricians or pediatric emergency medicine physicians. Patients are admitted to the OU if they are expected to meet discharge criteria within approximately 24 hours. A list of ICD-9-CM discharge diagnosis codes indicative of SSTIs was obtained from the Centers for Disease Control and Prevention. Electronic data sources within Intermountain Healthcare’s Electronic Data Warehouse were queried to identify patients who were admitted to the OU from the ED and satisfied at least one of the ICD-9-CM codes. Patients were excluded if they were >18 years of age, admitted to the OU for a different primary indication, admitted under a subspecialty service, or if there were insufficient data available. Electronic hospital records were the primary source of information. Paper charts were examined if electronic records were incomplete. All records were reviewed by 1 of 3 individuals (2 of the authors, RL and DS, and a research assistant). Data abstracted included hospital length of stay (LOS), patients’ age and sex, the location of infection, the presence of fever or abscess, prior antibiotic treatment, incision and drainage (I&D) prior to OU admission, prior history of an SSTI (with or without methicillin-resistant Staphylococcus aureus [MRSA]), history of MRSA exposure, white blood cell count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) if measured, and wound as well as blood culture results if obtained.
Outcome Measures The primary outcome was taken as successful OU discharge, defined as LOS of 26 hours or less. This time limit was chosen to reflect a 24-hour LOS target plus an allowance for the time to achieve actual discharge; a sensitivity analysis showed that the results presented here would not change significantly if a 24-hour limit were studied. Admission to the inpatient service before 26 hours was counted as OU failure. Because LOS requirements vary by institution, we also analyzed the OU discharge rate within 48 hours as a secondary outcome.
Statistical Analysis We analyzed categorical variables using Fisher’s exact test and continuous variables using nonparametric methods. In all cases, α was set at .05, and confidence intervals were calculated at the 95% level. We used
logistic regression to find adjusted odds ratios in multivariate modeling. To create binary (0 or 1) predictors for analysis, infection location was dichotomized by higher or lower success rate, and laboratory markers of inflammation were dichotomized around common clinical cutoffs (WBC > 10 000, CRP > 4 mg/L, ESR > 20 mm/h).
Results On records review, 853 patients matched eligibility criteria, of whom 394 (46%) were girls. Ages ranged from 0 through 17 years, with a median age of 5.2 years (interquartile range = 2.5-9 years); infants 4 mg/L and then by ESR > 20 mm/h (Table 3). Among the 276 patients in whom blood cultures were obtained, 8 blood cultures were positive for likely pathogens and 8 for likely contaminants. Thus, only 8 (2.9%) of the patients who had a blood culture performed or 0.9% of all patients studied had a true positive blood culture. It is not clear if these few true positives altered therapy or success.
Downloaded from cpj.sagepub.com at The University of Iowa Libraries on May 26, 2015
441
Lane et al Table 1. Patient Characteristics by Observation Unit Success or Failure. Patient Characteristic Mean age, years Female sex, no./total no. (%) History of fever, no./total no. (%) History of exposure to MRSA, no./total no. (%) Incision and drainage after admission, no./total no. (%) Mean WBC, ×1000 Mean CRP, mg/L Mean ESR, mm/h
OU Success
OU Failure
Difference Between Groups (95% CI)
P Value
6.3 264/597 (44.2) 258/597 (43.2) 28/593 (4.7) 84/594 (14.1)
5.6 130/256 (50.8) 162/256 (63.3) 22/254 (8.7) 57/255 (22.3)
0.7 (0.02, 1.34) 6.6% (−0.7%, 13.9%) 20.1% (12.9%, 27.2%) 3.9% (0.1%, 7.8%) 8.2% (2.4%, 14.0%)
.04 .08 (ns) 10 000 Need for I&D after admission Female sex
3.3 2.8 2.6 2.3 2.1 1.9 1.9 1.8 1.3
2.0, 5.2 1.7, 4.5 1.7, 3.9 1.7, 3.1 1.2, 3.4 1.1, 3.4 1.3, 2.9 1.2, 2.5 1.0, 1.7
