Vicente H. Gracias

Evolution in damage control for exsanguinating penetrating abdominal injury.

OBJECTIVE Damage control (DC) has proven valuable in exsanguinated patients. The purpose of this study was to quantify and qualify the impact of current damage control principles applied in a penetrating abdominal injury (PAI) population. METHODS Over a 3-year period (June 1997-May 2000), of 271 laparotomies for PAI, 24 patients underwent DC (8.9%). Demographics, injury grade, resuscitative and operative parameters, acid-base status, coagulation profiles, fluid/transfusion requirements, definitive repairs, abdominal closure, complications, and outcomes were reviewed. Data were compared with our DC experience a decade earlier. Fishers exact test was used for comparisons. RESULTS Overall survival improved for equivalent Injury Severity Score, Revised Trauma Score, TRISS, admission systolic blood pressure, operating room systolic blood pressure, and Penetrating Abdominal Trauma Index score. Solids (1.2 vs. 1.3), hollow organ (1.5 vs. 1.7), and major vascular injuries (0.5 vs. 0.8) per patient remain unchanged. Currently, there was less hypothermia with equivalent operating room times. In intensive care unit survivors, acid-base status was similar but coagulopathy and hypothermia were less severe. Definitive colon management has shifted from ostomies to anastomoses. Eventual fascial closure occurred in 14 of 19 (74%) compared with 12 of 14 (86%) in the historical group. There were three gastrointestinal fistulae (one pancreatic), one anastomotic leak, and three intra-abdominal abscesses. CONCLUSION Continued application of DC principles has led to improved survival with PAI. Better control of temperature, experience with the open abdomen, and intensive care unit care may be causative.

Packed red blood cell transfusion increases local cerebral oxygenation.

Objective:To determine a) whether packed red blood cell transfusion (RBCT) increases local brain tissue oxygen partial pressure (Pbto2) in a neurocritical care population; and b) what (if any) demographic, clinical, or physiologic variables mediate the assumed change. Design:Prospective observational study. Setting:A neurosurgical intensive care unit at a university-based level I trauma center and tertiary care hospital. Patients:Thirty-five consecutive volume-resuscitated patients with subarachnoid hemorrhage or traumatic brain injury, without cardiac disease, requiring Pbto2 monitoring and receiving RBCT were studied between October 2001 and December 2003. Interventions:None. Measurements and Main Results:The following physiologic variables were measured and compared 1 hr before and after RBCT: Pbto2, intracranial pressure, cerebral perfusion pressure, hemoglobin oxygen saturation (Sao2), Fio2, hemoglobin, and hematocrit. An increase in Pbto2 was observed in 26 of the 35 patients (74%). In nine patients, Pbto2 decreased after RBCT. The mean (±sd) increase in Pbto2 for all patients was 3.2 ± 8.8 mm Hg (p = .02), a 15% change from baseline (1 hr before RCBT). This Pbto2 increase was associated with a significant mean increase in hemoglobin and hematocrit after RBCT (1.4 ± 1.1 g/dL and 4.2% ± 3.3%, respectively; both p < .001). Cerebral perfusion pressure, Sao2, and Fio2 were similar before and after RBCT. Among the 26 patients whose Pbto2 increased, the mean increase in Pbto2 was 5.1 ± 9.4 mm Hg or a 49% mean increase (p < .01). Conclusions:RBCT is associated with an increase in Pbto2 in most patients with subarachnoid hemorrhage or traumatic brain injury. This mean increase appears to be independent of cerebral perfusion pressure, Sao2, and Fio2. Further study is required to determine why Pbto2 decreases in some patients after RBCT.

Transfusion of fresh frozen plasma in critically ill surgical patients is associated with an increased risk of infection

Objective:To determine whether there is an association between transfusion of fresh frozen plasma and infection in critically ill surgical patients. Design:Retrospective study. Setting:A 24-bed surgical intensive care unit in a university hospital. Patients:A total of 380 non-trauma patients who received fresh frozen plasma from 2004 to 2005 were compared with 2,058 nontrauma patients who did not receive fresh frozen plasma. Interventions:None. Measurements and Main Results:We calculated the relative risk of infectious complication for patients receiving and not receiving fresh frozen plasma. T-test allowed comparison of average units of fresh frozen plasma transfused to patients with and without infectious complications to describe a dose-response relationship. We used multivariate logistic regression analysis to evaluate the association between fresh frozen plasma and infectious complication, controlling for the effect of red blood cell transfusion, Acute Physiology and Chronic Health Evaluation II, and patient age. A significant association was found between transfusion of fresh frozen plasma and ventilator-associated pneumonia with shock (relative risk 5.42, 2.73–10.74), ventilator-associated pneumonia without shock (relative risk 1.97, 1.03–3.78), bloodstream infection with shock (relative risk 3.35, 1.69–6.64), and undifferentiated septic shock (relative risk 3.22, 1.84–5.61). The relative risk for transfusion of fresh frozen plasma and all infections was 2.99 (2.28–3.93). The t-test revealed a significant dose-response relationship between fresh frozen plasma and infectious complications (p = .02). Chi-square analysis showed a significant association between infection and transfusion of fresh frozen plasma in patients who did not receive concomitant red blood cell transfusion (p < .01), but this association was not significant in those who did receive red blood cells in addition to fresh frozen plasma. The association between fresh frozen plasma and infectious complications remained significant in the multivariate model, with an odds ratio of infection per unit of fresh frozen plasma transfused equal to 1.039 (1.013–1.067). This odds ratio resembled that noted for each unit of packed red blood cells, 1.074 (1.043–1.106). Conclusions:Transfusion of fresh frozen plasma is associated with an increased risk of infection in critically ill patients.

Brain tissue oxygen–directed management and outcome in patients with severe traumatic brain injury

OBJECT The object of this study was to determine whether brain tissue oxygen (PbtO(2))-based therapy or intracranial pressure (ICP)/cerebral perfusion pressure (CPP)-based therapy is associated with improved patient outcome after severe traumatic brain injury (TBI). METHODS Seventy patients with severe TBI (postresuscitation GCS score < or = 8), admitted to a neurosurgical intensive care unit at a university-based Level I trauma center and tertiary care hospital and managed with an ICP and PbtO(2) monitor (mean age 40 +/- 19 years [SD]) were compared with 53 historical controls who received only an ICP monitor (mean age 43 +/- 18 years). Therapy for both patient groups was aimed to maintain ICP < 20 mm Hg and CPP > 60 mm Hg. Patients with PbtO(2) monitors also had therapy to maintain PbtO(2) > 20 mm Hg. RESULTS Data were obtained from 12,148 hours of continuous ICP monitoring and 6,816 hours of continuous PbtO(2) monitoring. The mean daily ICP and CPP and the frequency of elevated ICP (> 20 mm Hg) or suboptimal CPP (< 60 mm Hg) episodes were similar in each group. The mortality rate was significantly lower in patients who received PbtO(2)-directed care (25.7%) than in those who received conventional ICP and CPP-based therapy (45.3%, p < 0.05). Overall, 40% of patients receiving ICP/CPP-guided management and 64.3% of those receiving PbtO(2)-guided management had a favorable short-term outcome (p = 0.01). Among patients who received PbtO(2)-directed therapy, mortality was associated with lower mean daily PbtO(2) (p < 0.05), longer durations of compromised brain oxygen (PbtO(2) < 20 mm Hg, p = 0.013) and brain hypoxia (PbtO(2) < 15 mm Hg, p = 0.001), more episodes and a longer cumulative duration of compromised PbtO(2) (p < 0.001), and less successful treatment of compromised PbtO(2) (p = 0.03). CONCLUSIONS These results suggest that PbtO(2)-based therapy, particularly when compromised PbtO(2) can be corrected, may be associated with reduced patient mortality and improved patient outcome after severe TBI.

Intensivist use of hand-carried ultrasonography to measure IVC collapsibility in estimating intravascular volume status: correlations with CVP.

BACKGROUND Volume status assessment is an important aspect of patient management in the surgical intensive care unit (SICU). Echocardiologist-performed measurement of IVC collapsibility index (IVC-CI) provides useful information about filling pressures, but is limited by its portability, cost, and availability. Intensivist-performed bedside ultrasonography (INBU) examinations have the potential to overcome these impediments. We used INBU to evaluate hemodynamic status of SICU patients, focusing on correlations between IVC-CI and CVP. STUDY DESIGN Prospective evaluation of hemodynamic status was conducted on a convenience sample of SICU patients with a brief (3 to 10 minutes) INBU examination. INBU examinations were performed by noncardiologists after 3 hours of didactics in interpreting and acquiring two-dimensional and M-mode images, and > or =25 proctored examinations. IVC-CI measurements were compared with invasive CVP values. RESULTS Of 124 enrolled patients, 101 had CVP catheters (55 men, mean age 58.3 years, 44.6% intubated). Of these, 18 patients had uninterpretable INBU examinations, leaving 83 patients with both CVP monitoring devices and INBU IVC evaluations. Patients in three IVC-CI ranges (<0.20, 0.20 to 0.60, and >0.60) demonstrated significant decrease in mean CVP as IVC-CI increased (p = 0.023). Although <5% of patients with IVC-CI <0.20 had CVP <7 mmHg, >40% of this group had a CVP >12 mmHg. Conversely, >60% of patients with IVC-CI >0.6 had CVP <7 mmHg. CONCLUSIONS Measurements of IVC-CI by INBU can provide a useful guide to noninvasive volume status assessment in SICU patients. IVC-CI appears to correlate best with CVP in the setting of low (<0.20) and high (>0.60) collapsibility ranges. Additional studies are needed to confirm and expand on findings of this study.

Brain tissue oxygen and outcome after severe traumatic brain injury: a systematic review.

Objective:In this study, available medical literature were reviewed to determine whether brain hypoxia as measured by brain tissue oxygen (Bto2) levels is associated with increased risk of poor outcome after traumatic brain injury (TBI). A secondary objective was to examine the safety profile of a direct BtO2 probe. Data Source and Extraction:Clinical studies published between 1993 and 2008 were identified from electronic databases, Index Medicus, bibliographies of pertinent articles, and expert consultation. The following inclusion criteria were applied for outcome analysis: 1) more than 10 patients described, 2) use of a direct Bto2 monitor, 3) brain hypoxia defined as Bto2 <10 mm Hg for >15 or 30 minutes, 4) 6-month outcome data, and 5) clear reporting of patient outcome associated with Bto2. For the analysis, each selected article had to have adequate data to determine odds ratios (ORs) and confidence intervals (CIs). Thirteen studies met the initial inclusion criteria and three were included in the final outcome analysis. Safety data were abstracted from any report where it was mentioned. Data Synthesis:The three studies included 150 evaluable patients with severe TBI (Glasgow Coma Scale ≤8). Brain hypoxia was identified in 71 (47%) of these patients. Among the patients with brain hypoxia, 52 (73%) had unfavorable outcome including 39 (55%) who died. In the absence of brain hypoxia, 34 (43%) patients had an unfavorable outcome, including 17 (22%) who died. Overall brain hypoxia (Bto2 <10 mm Hg >15 minutes) was associated with worse outcome (OR 4.0; 95% CI 1.9–8.2) and increased mortality (OR 4.6; 95% CI 2.2–9.6). We reviewed published safety data; in 292 patients monitored with a Bto2 probe, only two adverse events were reported. Conclusion:Summary results indicate that brain hypoxia (<10 mm Hg) is associated with worse outcome after severe TBI and that Bto2 probes are safe. These results imply that treating patients to increase Bto2 may improve outcome after severe TBI. This question will require further study.

Hepatic angiography in patients undergoing damage control laparotomy.

OBJECTIVE Patients undergoing damage control (DC) laparotomy require intensive and aggressive resuscitation, and may require additional maneuvers to control parenchymal bleeding. Those patients suffering significant liver injury are at high risk for arterial bleeding deep within the liver, and many require hepatic angiography in addition to hepatic packing. We reviewed our experience with hepatic angiography, and sought to determine its safety in the DC population of penetrating and blunt trauma patients. METHODS A 3-year (June 1997-May 2000) retrospective review generated 37 DC patients. Patients sustaining hepatic trauma constituted the study group. Patients undergoing angiography in addition to DC laparotomy were compared with the group of patients not undergoing angiography. Data regarding mechanism of injury, patient demographics, extent of hepatic injury, and presence of associated injuries were collected. Physiologic parameters including vital signs at admission, lowest pH and base excess in the operating room, and lactate levels in the intensive care unit, as well as volumes of fluid resuscitation throughout all phases of DC were examined. Complications including death, intra-abdominal processes, acute respiratory distress syndrome and/or multiple organ dysfunction syndrome, and acute renal failure were reviewed. RESULTS Nineteen patients (51%) had hepatic trauma and underwent perihepatic packing as a part of DC laparotomy. Eleven had sustained penetrating injury and 8 had blunt injury. There was 1 American Association for the Surgery of Trauma grade I, 5 grade II, 3 grade III, and 10 grade IV injuries. Nine patients in the study population underwent angiography, and eight of these were hepatic artery angiograms. One hepatic angiogram was obtained before operation and seven were obtained in the immediate postoperative period. Six underwent embolization of bleeding hepatic vessels, for a therapeutic liver angiography rate of 75%. There was no statistical difference in physiologic parameters or fluid requirements between the patients who underwent angiography and those who did not. There were no mishaps or complications from angiography or while in the angiography suite. CONCLUSION Hepatic angiography is a safe adjunct to the principles of damage control. It has a high therapeutic ratio, with no significant untoward effect in this small study population.

The impact of development of acute lung injury on hospital mortality in critically ill trauma patients

Objective:The additional impact of development of acute lung injury on mortality in severely-injured trauma patients beyond baseline severity of illness has been questioned. We assessed the contribution of acute lung injury to in-hospital mortality in critically ill trauma patients. Design:Prospective cohort study. The contribution of acute lung injury to in-hospital mortality was evaluated in two ways. First, multivariable logistic regression models were used to test the independent association of acute lung injury with in-hospital mortality while adjusting for baseline confounding variables. Second, causal pathway models were used to estimate the amount of the overall association of baseline severity of illness with in-hospital mortality that is attributable to the interval development of acute lung injury. Setting:Academic level 1 trauma center. Patients:Two hundred eighty-three critically ill trauma patients without isolated head injury and with an Injury Severity Score ≥16 were evaluated for development of acute lung injury in the first 5 days after trauma. Measurements and Main Results:Of the 283 patients, 38 (13.4%) died. The unadjusted mortality rate was nearly three-fold greater in the acute lung injury group (23.9% vs. 8.4%; odds ratio = 3.36; 95% confidence interval 1.67-6.77; p = 0.001). Acute lung injury remained an independent risk factor for death after adjustment for age, baseline Acute Physiologic and Chronic Health Evaluation III score, Injury Severity Score, and blunt mechanism of injury (odds ratio = 2.87; 95% confidence interval 1.29-6.37; p = 0.010). Forty percent of the total association of the baseline Acute Physiologic and Chronic Health Evaluation III score with mortality occurred via an indirect association through acute lung injury, and the remaining 60% via a direct effect. Conclusions:Development of acute lung injury in critically ill trauma patients without isolated head injury contributes independently to in-hospital mortality beyond baseline severity of illness measures. In addition, a significant portion of the association between baseline illness severity and risk of death in these patients might be explained by the interval development of acute lung injury.

Retained Surgical Items: A Problem Yet to Be Solved

BACKGROUND Retained surgical items (RSI) continue to occur. Large RSI studies are few due to low RSI frequency in single institutions and the medicolegal implications. Consequently, RSI risks are not fully defined, with discrepancies persisting among published studies. The goals of this study were to better define risk factors for RSI, to clarify previously discrepant risk factors, and to evaluate other potential contributors to RSI occurrence, such as trainee presence during an operation. STUDY DESIGN Multicenter case-match study of RSI risk factors was conducted between January 2003 and December 2009. Cases complicated by RSI were identified at participating centers using clinical quality improvement and adverse event reporting data. Case match controls (non-RSI) were selected from same or similar-type cases performed at each respective institution. Retained surgical item risk factors were evaluated by univariate and multivariate conditional logistic regression. RESULTS Fifty-nine RSIs and 118 matched controls were analyzed (RSI incidence 1 in 6,975 or 59 in 411,526). Retained surgical items occurred despite use of confirmatory x-rays (13 of 27 instances) and/or radiofrequency tagging (2 of 32 instances). Among previously discrepant results, we confirmed that body mass index, unexpected intraoperative events, and procedure duration were associated with increased RSI risk. The occurrence of any safety variance, and specifically an incorrect count at any time during the procedure, was associated with elevated RSI risk. Trainee presence was associated with 70% lower RSI risk compared with trainee absence. CONCLUSIONS Longer duration of surgery, safety variances, and incorrect counts during the procedure result in elevated RSI risk. The possible positive influence of trainee presence on RSI risk deserves additional study. Our findings highlight the need for zero tolerance for safety omissions, continued study and development of novel approaches to RSI reduction, and establishing anonymous RSI reporting systems to better track both the incidence and risks associated with this problem, which has yet to be solved.

Integrating emergency general surgery with a trauma service: impact on the care of injured patients.

BACKGROUND There has been considerable discussion on the national level on the future of trauma surgery as a specialty. One of the leading directions for the field is the integration of emergency general surgery as a wider and more attractive scope of practice. However, there is currently no information on how the addition of an emergency general surgery practice will affect the care of injured patients. We hypothesized that the care of trauma patients would be negatively affected by adding emergency general surgery responsibilities to a trauma service. METHODS Our institution underwent a system change in August 2001, where an emergency general surgery (ES) practice was added to an established trauma service. The ES practice included emergency department and in-house consultations for all urgent surgical problems except thoracic and vascular diseases. There were no trauma staff changes during the study period. Trauma registry data (demographics, injuries, injury severity, and procedures) and performance improvement data (peer-review judgments for all identified errors, denied days, audit filters, and deaths) were abstracted for two 15-month periods surrounding this system change. Chi-square, Fishers exact, and t tests provided between-group comparisons. RESULTS The trauma staff evaluated a total of 5,874 patients during the 30-month study. There were 1,400 (51%) trauma admissions in the pre-ES group and 1,504 (48%) in the post-ES group, of which 1,278 and 1,434, respectively, met severity criteria for report to our statewide database (Pennsylvania Trauma Outcome Study [PTOS]). There were 163 (12.7% of PTOS) deaths in the pre-ES group compared with 171 (11.9% PTOS) deaths in the post-ES group (p = not significant [NS]). There was one death determined to be preventable by the peer review process for the pre-ES group, and none in the post-ES group. Both groups had 10 potentially preventable deaths, with the remaining mortalities being categorized as nonpreventable (p = NS). Unexpected deaths by TRISS methodology were 36 (2.8%) and 41 (2.9%) for the two groups, respectively (p = NS). There was no difference in the number of provider-specific complications between the groups (23, [1.8%] vs. 19 [1.3%], p = NS). The addition of emergency surgery has resulted in an additional average daily workload of 1.3 cases and 1.2 admissions. CONCLUSION Despite an increase in trauma volume over the study period, the addition of emergency surgery to a trauma service did not affect the care of injured patients. The concept of adding emergency surgery responsibilities to trauma surgeons appears to be a valid way to increase operative experience without compromising care of the injured patient.