Alison Wilson

Increases in Endotracheal Tube Resistance Are Unpredictable Relative to Duration of Intubation

BACKGROUND Accumulated secretions after intubation can affect the resistance of an endotracheal tube (ETT). Our objective was to measure extubated patient tubes and size-matched controls to evaluate differences in resistance. METHODS New ETTs, with internal diameters of 7.0 through 8.5 mm, were tested as controls to establish the resistance of each size group as measured by pressure drop. Measurements were obtained using a mass flowmeter and pressure transducer. Pressure drop was measured at three flow rates. Seventy-one patient ETTs were evaluated after extubation by an identical method and compared with controls. RESULTS In each control group, pressure drop was tightly clustered with low variation and no overlap between sizes. A total of 73 to 79% of the patient ETTs had a pressure drop of > 3 SDs of size-matched controls at all flow rates. Pressure drop in 48 to 56% (across three flow rates) of extubated tubes was equivalent to the next smaller size of controls. At 60 and 90 L/min, 10% and 15% of patient tubes, respectively, had the pressure drop of a control tube three sizes smaller. The pressure drop was unpredictable relative to the duration of intubation. CONCLUSIONS Organized secretions can significantly increase resistance as measured by the pressure drop of ETTs. The degree of change was highly variable, occurs in all sizes, and was unrelated to the duration of intubation. The performance of an ETT may be comparable to new tubes one to four sizes smaller. This may impact the tolerance of ventilator weaning.

Impact of a Multimodal Antimicrobial Stewardship Program on Pseudomonas aeruginosa Susceptibility and Antimicrobial Use in the Intensive Care Unit Setting

Objective. To study the impact of our multimodal antibiotic stewardship program on Pseudomonas aeruginosa susceptibility and antibiotic use in the intensive care unit (ICU) setting. Methods. Our stewardship program employed the key tenants of published antimicrobial stewardship guidelines. These included prospective audits with intervention and feedback, formulary restriction with preauthorization, educational conferences, guidelines for use, antimicrobial cycling, and de-escalation of therapy. ICU antibiotic use was measured and expressed as defined daily doses (DDD) per 1,000 patient-days. Results. Certain temporal relationships between antibiotic use and ICU resistance patterns appeared to be affected by our antibiotic stewardship program. In particular, the ICU use of intravenous ciprofloxacin and ceftazidime declined from 148 and 62.5 DDD/1,000 patient-days to 40.0 and 24.5, respectively, during 2004 to 2007. An increase in the use of these agents and resistance to these agents was witnessed during 2008–2010. Despite variability in antibiotic usage from the stewardship efforts, we were overall unable to show statistical relationships with P. aeruginosa resistance rate. Conclusion. Antibiotic resistance in the ICU setting is complex. Multimodal stewardship efforts attempt to prevent resistance, but such programs clearly have their limits.

Advanced endotracheal tube biofilm stage, not duration of intubation, is related to pneumonia.

BACKGROUND: Biofilms are complex communities of living bacteria surrounded by a protective glycocalyx. Biofilms have been implicated in the development of infections such as dental caries and hardware infections. Biofilms form on endotracheal tubes (ETT) and can impact airway resistance. The lifecycle of a biofilm has four stages. We hypothesize that there is a relationship between the stage of biofilm on the ETT and development of pneumonia. METHODS: Thirty-two ETT were analyzed for biofilms and staged. Staging was performed by a microbiologist blinded to all patient information. Data included development of pneumonia, duration of intubation, comorbidities, and microbiology. Pneumonia was defined as presence of fever, WBC >12 K or <4 K, infiltrate on chest X-ray, and purulent sputum with +lower airway culture (bronchoalveolar lavage or brush). Statistics were performed by a biostatistician; p < 0.05 defined significance. RESULTS: There were 11 women and 21 men with a mean age of 50 years. Mean intensive care unit days were 13 (standard deviation ± 9.9) and mean length of intubation was 7.4 days (standard deviation ± 5.0). Half (16 of 32) the patients developed pneumonia while intubated. Eight of 10 patients with a stage IV biofilm had pneumonia. There was a relationship between increasing biofilm stage with the incidence of pneumonia (p < 0.05). Stage IV biofilms were associated with pneumonia (p < 0.02). There was no relationship to duration of intubation, patient age or hospital stay and biofilm stage. CONCLUSIONS: Advanced biofilm stage (stage IV) is associated with pneumonia. Duration of intubation does not predict biofilm stage.

Intra-abdominal pressure and the morbidly obese patients: the effect of body mass index.

BACKGROUND Abdominal compartment syndrome and intra-abdominal hypertension cause morbidity and mortality. Body mass index (BMI) may affect intra-abdominal pressure (IAP). Knowledge of the baseline IAP in the obese and the effect of BMI are not clearly defined. METHODS IAPs were measured in 37 morbidly obese patients undergoing elective gastric bypass. Measurements were obtained via bladder pressure using a standard technique. IAP was measured after intubation (P1) and postoperatively after extubation (P2). Data collected included age, gender, BMI, previous surgeries, comorbidities, IAP, and laparoscopic versus open procedure. RESULTS Mean BMI was 47.7 kg/m (range, 37-71.8 kg/m), and mean age was 45 years (range, 32-64 years). P1 mean was 9.4 mm Hg +/- 0.6 mm Hg, and P2 mean was 10.0 mm Hg +/- 0.6 mm Hg. Laparoscopic versus open procedure was unrelated to postoperative IAP. Previous surgeries and comorbidities were unrelated to IAP. P1 increased as BMI increased. For each unit increase of BMI, IAP increased by 0.14 mm Hg +/- 0.07 mm Hg (p = 0.05). Higher BMI and age were independent predictors of increased P2, with IAP increased 0.23 mm Hg +/- 0.07 mm Hg for each unit BMI (p = 0.0015) and 0.20 mm Hg +/- 0.06 mm Hg for each year increase in age (p = 0.0014). CONCLUSIONS Baseline IAP in the obese is greater than normal weight population (0-6 mm Hg), but not in range of intra-abdominal hypertension (>12 mm Hg). Postoperative status is unrelated to IAP. Elevated BMI does impact IAP, but the incremental value is small. Markedly increased IAP should not be attributed solely to elevated BMI and should be recognized as a pathologic condition.

Pneumatosis Intestinalis Predictive Evaluation Study: A multicenter epidemiologic study of the American Association for the Surgery of Trauma

BACKGROUND Our group has previously published a retrospective review defining variables predictive of transmural bowel ischemia in the setting of pneumatosis intestinalis (PI). We hypothesize this prospective study will confirm the findings of the retrospective review, enhancing legitimacy to the predictive factors for pathologic PI previously highlighted. METHODS Data were collected using the Research Electronic Data Capture. Forward logistic regression was utilized to identify independent predictors for pathologic PI. Statistical significance was defined as p ⩽ 0.05. RESULTS During the 3-year study period, 127 patients with PI were identified. Of these, 79 had benign disease, and 49 pathologic PI defined by the presence of transmural ischemia during surgical exploration or autopsy. Laboratory values such as elevated international normalized ratio (INR), decreased hemoglobin, and a lactate value of greater than 2.0 mmol/L were predictive of pathologic PI, as well as clinical factors including adynamic ileus, peritoneal signs on physical examination, sepsis, and hypotension. The location was also a significant factor, as patients with small bowel PI had a higher incidence of transmural ischemia than colonic PI. On multiple logistic regression, lactate value of greater than 2.0 mmol/L (odds ratio, 5.1, 1.3–19.5; p = 0.018), elevated INR (odds ratio, 3.2, 1.1–9.6; p = 0.031), peritonitis (15.0, 2.9–78; p = 0.001), and decreased hemoglobin (0.70, 0.50–0.97, 0.031) remained significant predictors of transmural ischemia (area under the curve, 0.90; 0.83–0.97). A lactate value of 2.0 mmol/L or greater and peritonitis are common factors between the retrospective review and this prospective study. CONCLUSIONS We recommend surgical exploration to be strongly considered for those PI patients presenting also with a lactate greater than 2 mmol/L and/or peritonitis. We suggest strong suspicion for necrosis in those patient with PI and small bowel involvement, ascites on computed tomography scan, adynamic ileus, anemia, and a high INR. LEVEL OF EVIDENCE Prognostic study, level II; therapeutic study, level II.

A matched-control evaluation of an antifungal bundle in the intensive care unit at a university teaching hospital

Background Antimicrobial use bundles are becoming a common means of implementing antimicrobial stewardship initiatives in the hospital setting. Although the utility of these bundles has been described for many disease states, their adoption for antifungal therapy management is largely unknown. Objective Our objective was to assess the utility of an antifungal bundle protocol in limiting excessive use of echinocandins in the intensive-care inpatient setting. Methods In this matched-control evaluation, pre-protocol control patients were matched with each prospective patient in a 2:1 ratio using five demographic and clinical characteristics. The impact of the antifungal bundle protocol on caspofungin days of therapy, drug costs, and adherence to bundle criteria was assessed. Results A significant reduction in median days of caspofungin therapy (4.00 vs. 2.00 days, p = 0.001) was found in the bundle group. Most of this reduction in use was realized in the medical ICU (p = 0.002) as opposed to the surgical ICU (p = 0.188). Conclusions Use of an antifungal bundle approach appears to facilitate a reduction in caspofungin use in the ICU without adversely affecting patient outcomes. Further trials are needed to assess the utility of such bundles in providing antimicrobial stewardship for antifungal drug use.

Do we glow? Evaluation of trauma team work habits and radiation exposure.

BACKGROUND Health care workers’ potential exposure to ionizing radiation has increased. Annual radiation exposure limit for the general public per US Nuclear Regulatory Commission is 100 mrem (1 mSv). The whole-body annual occupational radiation exposure limit is 5,000 mrem (50 mSv). Studies have been done to evaluate patient radiation exposure. To date, there has been no study to evaluate the radiation exposure of trauma team members or evaluate their behaviors and attitudes. METHODS Forty primary providers (residents, physician assistants) rotating on the trauma service at an American College of Surgeons Level 1 trauma center participated. Dosimeters were worn by participants, and the radiation doses were measured monthly. A survey detailing the frequency of involvement in radiographic studies, use of protective equipment, and knowledge of education programs was completed monthly. RESULTS The range of radiation measured was 1 mrem to 56 mrem, with an average effective dose of 10 mrem per month. Thirty-two (80%) of 40 reported daily exposure to x-rays and 28 (70%) of 40 to computed tomographic scans. Thirty-four (85%) of 40 reported that they never or seldom wore lead apron in trauma bay as opposed to 1 (3%) of 40 who failed to wear it during fluoroscopy. Twenty (50%) reported that an apron was not available, while 20 (50%) reported that it was too hot or did not fit. Thirty-nine (97%) of 40 reported that they received training in radiation safety. CONCLUSION Despite inconsistent use of protective equipment by resident staff, the actual radiation exposure remains low. Hospitals should be sure lead aprons and collars are available. Additional education concerning the availability of programs during pregnancy is needed. LEVEL OF EVIDENCE Epidemiologic study, level III.

The effect of craniectomy size on mortality, outcome, and complications after decompressive craniectomy at a rural trauma center.

Introduction: Decompressive craniectomy (DC) has increasing support with current studies suggesting an improvement in both survival rates and outcomes with this intervention. However, questions surround this procedure; specifically, no evidence has indicated the optimal craniectomy size. Larger craniectomy is thought to better decrease intracranial pressure, but with a possible increase in complication rates. Our hypothesis is that a larger craniectomy may improve mortality and outcome, but may increase complication rates. Materials and Methods: A retrospective observational therapeutic study was undertaken to determine if craniectomy size is related to complication rates, mortality, or outcome. Our institutions Trauma Registry was searched for patients undergoing DC. Craniectomy size was measured by antero-posterior (AP) diameter. Mortality, outcome (through admission and discharge Glasgow Coma Score and Glasgow Outcome Scale), and complications (such as re-bleeding, re-operation, hygroma, hydrocephalus, infection, and syndrome of the trephined) were noted. Complications, mortality, and outcome were then compared to craniectomy size, to determine if any relation existed to support our hypothesis. Results: 20 patients met criteria for inclusion in this study. Craniectomy size as measured by AP diameter was correlated with a statistically significant improvement in mortality within the group. All patients with a craniectomy size less than 10 cm died. However, outcome was not significantly related to craniectomy size in the group. Similarly, complication rates did not differ significantly compared to craniectomy size. Discussion: This study provides Level 3 evidence that craniectomy size may be significantly related to improved mortality within our group, supporting our initial hypothesis; however, no significant improvement in outcome was seen. Similarly, in contrast to our hypothesis, complication rates did not significantly correlate with craniectomy size.

Mortality after emergent trauma laparotomy: A multicenter, retrospective study

BACKGROUND Two decades ago, hypotensive trauma patients requiring emergent laparotomy had a 40% mortality. In the interim, multiple interventions to decrease hemorrhage-related mortality have been implemented but few have any documented evidence of change in outcomes for patients requiring emergent laparotomy. The purpose of this study was to determine current mortality rates for patients undergoing emergent trauma laparotomy. METHODS A retrospective cohort of all adult, emergent trauma laparotomies performed in 2012 to 2013 at 12 Level I trauma centers was reviewed. Emergent trauma laparotomy was defined as emergency department (ED) admission to surgical start time in 90 minutes or less. Hypotension was defined as arrival ED systolic blood pressure (SBP) ⩽90 mm Hg. Cause and time to death was also determined. Continuous data are presented as median (interquartile range [IQR]). RESULTS One thousand seven hundred six patients underwent emergent trauma laparotomy. The cohort was predominately young (31 years; IQR, 24–45), male (84%), sustained blunt trauma (67%), and with moderate injuries (Injury Severity Score, 19; IQR, 10–33). The time in ED was 24 minutes (IQR, 14–39) and time from ED admission to surgical start was 42 minutes (IQR, 30–61). The most common procedures were enterectomy (23%), hepatorrhaphy (20%), enterorrhaphy (16%), and splenectomy (16%). Damage control laparotomy was used in 38% of all patients and 62% of hypotensive patients. The Injury Severity Score for the entire cohort was 19 (IQR, 10–33) and 29 (IQR, 18–41) for the hypotensive group. Mortality for the entire cohort was 21% with 60% of deaths due to hemorrhage. Mortality in the hypotensive group was 46%, with 65% of deaths due to hemorrhage. CONCLUSION Overall mortality rate of a trauma laparotomy is substantial (21%) with hemorrhage accounting for 60% of the deaths. The mortality rate for hypotensive patients (46%) appears unchanged over the last two decades and is even more concerning, with almost half of patients presenting with an SBP of 90 mm Hg or less dying.

A team approach to effectively discharge trauma patients

BACKGROUND Trauma patients represent a high-volume and high-acuity population. This makes discharge planning difficult. Discharged by noon is a metric shown to correlate with hospital throughput. Improvements in efficiency will be needed to improve resource utilization and increase discharge by noon rate. This study aimed to evaluate the impact of a standardized discharge team on length of stay and discharge by noon. MATERIALS AND METHODS A university level I trauma center implemented a discharge team composed of a trauma attending and an advanced practice provider. This team is tasked with evaluating patients on the discharge list daily. This allowed patients ready for discharge to be evaluated and discharged before noon. A retrospective review was performed to analyze discharge by noon rates before and after implementation of the discharge team. RESULTS A total of 3053 patients were discharged before the implementation of the discharge team and 3801 after. Discharges by noon increased from 25.5% to 51.2% in the post. For patients with an injury severity score >15, this same improvement was seen, 22.5% to 51.9%. Similar improvements were seen when controlling for final discharge disposition and primary payer status. CONCLUSIONS By establishing a separate discharge team, large improvements can be seen in the discharge by noon rate. These improvements were maintained when controlling for injury severity score, final discharge disposition, and insurance status. Significant savings are possible in both charges to the patient and direct costs to the facility. The utilization of a discharge team should be considered at similar facilities.