Low-molecular-weight heparin compared with unfractionated heparin in critically ill COVID-19 patients.

BACKGROUND: Thrombosis in COVID-19 worsens mortality. In our study, we sought to investigate how the dose and type of anticoagulation (AC) can influence patient outcomes. METHODS: This is a single-center retrospective analysis of critically ill intubated patients with COVID-19, comparing low-molecular-weight heparin (LMWH) and unfractionated heparin (UFH) at therapeutic and prophylactic doses. Of 218 patients, 135 received LMWH (70 prophylactic, 65 therapeutic) and 83 UFH (11 prophylactic, 72 therapeutic). The primary outcome was mortality. Secondary outcomes were thromboembolic complications confirmed on imaging and major bleeding complications. Cox proportional-hazards regression models were used to determine whether the type and dose of AC were independent predictors of survival. We performed Kaplan-Meier survival analysis to compare the cumulative survivals. RESULTS: Overall, therapeutic AC, with either LMWH (65% vs 79%, P = .09) or UFH (32% vs 46%, P = .73), conveyed no survival benefit over prophylactic AC. UFH was associated with a higher mortality rate than LMWH (66% vs 28%, P = .001), which was also evident in the multivariable analysis (LMWH vs UFH mortality, hazard ratio: 0.47, P = .001) and in the Kaplan-Meier survival analysis. Thrombotic and bleeding complications did not depend on the AC type (prophylactic LMWH vs UFH: thrombosis P = .49, bleeding P = .075; therapeutic LMWH vs UFH: thrombosis P = .5, bleeding P = .17). When comparing prophylactic with therapeutic AC, the rate of both thrombotic and bleeding complications was higher with the use of LMWH compared with UFH. In addition, transfusion requirements were significantly higher with both therapeutic LMWH and UFH. CONCLUSIONS: Among intubated critically ill COVID-19 intensive care unit patients, therapeutic AC, with either LMWH or UFH, conveyed no survival benefit over prophylactic AC. AC with LMWH was associated with higher cumulative survival compared with AC with UFH.

Aggressive Anticoagulation May Decrease Mortality in Obese Critically Ill COVID-19 Patients.

BACKGROUND: Obesity is a widely accepted risk factor for the development of severe COVID-19. We sought to determine the survival benefit of early initiation of aggressive anticoagulation in obese critically ill COVID-19 patients. METHODS: We retrospectively reviewed 237 intubated patients at a single academic accredited bariatric center and stratified them based on their BMI into 2 groups, obese (BMI > 30) and non-obese (BMI ≤ 30). We used chi-square tests to compare categorical variables such as age and sex, and two-sample t-tests or Mann Whitney U-tests for continuous variables, including important laboratory values. Cox proportional-hazards regression models were utilized to determine whether obesity was an independent predictor of survival and multivariable analysis was performed to compare risk factors that were deemed significant in the univariable analysis. Survival with respect to BMI and its association with level of anticoagulation in the obese cohort was evaluated using Kaplan-Meier models. RESULTS: The overall mortality in the obese and non-obese groups was similar at 47% and 44%, respectively (p = 0.65). Further analysis based on the level of AC showed that obese patients placed on early aggressive AC protocol had improved survival compared to obese patients who did not receive protocol based aggressive AC (ON-aggressive AC protocol 26% versus OFF-aggressive AC protocol 61%, p = 0.0004). CONCLUSIONS: The implementation of early aggressive anticoagulation may balance the negative effects of obesity on the overall mortality in critically ill COVID-19 patients.

Acute Gastrointestinal Injury and Feeding Intolerance as Prognostic Factors in Critically Ill COVID-19 Patients.

BACKGROUND: Although acute gastrointestinal injury (AGI) and feeding intolerance (FI) are known independent determinants of worse outcomes and high mortality in intensive care unit (ICU) patients, the incidence of AGI and FI in critically ill COVID-19 patients and their prognostic importance have not been thoroughly studied. METHODS: We reviewed 218 intubated patients at Stony Brook University Hospital and stratified them into three groups based on AGI severity, according to data collected in the first 10 days of ICU course. We used chi-square test to compare categorical variables such as age and sex and two-sample t-test or Mann-Whitney U-tests for continuous variables, including important laboratory values. Cox proportional hazards regression models were utilized to determine whether AGI score was an independent predictor of survival, and multivariable analysis was performed to compare risk factors that were deemed significant in the univariable analysis. We performed Kaplan-Meier survival analysis based on the AGI score and the presence of FI. RESULTS: The overall incidence of AGI was 95% (45% AGI I/II, 50% AGI III/IV), and FI incidence was 63%. Patients with AGI III/IV were more likely to have prolonged mechanical ventilation (22 days vs 16 days, P-value <0.002) and higher mortality rate (58% vs 28%, P-value <0.001) compared to patients with AGI 0/I/II. This was confirmed with multivariable analysis which showed that AGI score III/IV was an independent predictor of higher mortality (AGI III/IV vs AGI 0/I/II hazard ratio (HR), 2.68; 95% confidence interval (CI), 1.69-4.25; P-value <0.0001). Kaplan-Meier survival analysis showed that both AGI III/IV and FI (P-value <0.001) were associated with worse outcomes. Patients with AGI III/IV had higher daily and mean D-dimer and CRP levels compared to AGI 0/I/II (P-value <0.0001). CONCLUSIONS: The prevalence of AGI and FI among critically ill COVID-19 patients was high. AGI grades III/IV were associated with higher risk for prolonged mechanical ventilation and mortality compared to AGI 0/I/II, while it also correlated with higher D-dimer and C-reactive protein (CRP) levels. FI was independently associated with higher mortality. The development of high-grade AGI and FI during the first days of ICU stay can serve as prognostic tools to predict outcomes in critically ill COVID-19 patients.

D-Dimer-Driven Anticoagulation Reduces Mortality in Intubated COVID-19 Patients: A Cohort Study With a Propensity-Matched Analysis.

Objective: Examine the possible beneficial effects of early, D-dimer driven anticoagulation in preventing thrombotic complications and improving the overall outcomes of COVID-19 intubated patients. Methods: To address COVID-19 hypercoagulability, we developed a clinical protocol to escalate anticoagulation based on serum D-dimer levels. We retrospectively reviewed all our first 240 intubated patients with COVID-19. Of the 240, 195 were stratified into patients treated based on this protocol (ON-protocol, n = 91) and the control group, patients who received standard thromboprophylaxis (OFF-protocol, n = 104). All patients were admitted to the Stony Brook University Hospital intensive care units (ICUs) between February 7th, 2020 and May 17, 2020 and were otherwise treated in the same manner for all aspects of COVID-19 disease. Results: We found that the overall mortality was significantly lower ON-protocol compared to OFF-protocol (27.47 vs. 58.66%, P < 0.001). Average maximum D-dimer levels were significantly lower in the ON-protocol group (7,553 vs. 12,343 ng/mL), as was serum creatinine (2.2 vs. 2.8 mg/dL). Patients with poorly controlled D-dimer levels had higher rates of kidney dysfunction and mortality. Transfusion requirements and serious bleeding events were similar between groups. To address any possible between-group differences, we performed a propensity-matched analysis of 124 of the subjects (62 matched pairs, ON-protocol and OFF-protocol), which showed similar findings (31 vs. 57% overall mortality in the ON-protocol and OFF-protocol group, respectively). Conclusions: D-dimer-driven anticoagulation appears to be safe in patients with COVID-19 infection and is associated with improved survival. What This Paper Adds: It has been shown that hypercoagulability in patients with severe COVID-19 infection leads to thromboembolic complications and organ dysfunction. Anticoagulation has been variably administered to these patients, but it is unknown whether routine or escalated thromboprophylaxis provides a survival benefit. Our data shows that escalated D-dimer driven anticoagulation is associated with improved organ function and overall survival in intubated COVID-19 ICU patients at our institution. Importantly, we found that timely escalation of this anticoagulation is critical in preventing organ dysfunction and mortality in patients with severe COVID-19 infection.

An Evolving Clinical Need: Discordant Oxygenation Measurements of Intubated COVID-19 Patients.

Since the first appearance of the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) earlier this year, clinicians and researchers alike have been faced with dynamic, daily challenges of recognizing, understanding, and treating the coronavirus disease 2019 (COVID-19) due to SARS-CoV-2. Those who are moderately to severely ill with COVID-19 are likely to develop acute hypoxemic respiratory failure and require administration of supplemental oxygen. Assessing the need to initiate or titrate oxygen therapy is largely dependent on evaluating the patient's existing blood oxygenation status, either by direct arterial blood sampling or by transcutaneous arterial oxygen saturation monitoring, also referred to as pulse oximetry. While the sampling of arterial blood for measurement of dissolved gases provides a direct measurement, it is technically challenging to obtain, is painful to the patient, and can be time and resource intensive. Pulse oximetry allows for non-invasive, real-time, continuous monitoring of the percent of hemoglobin molecules that are saturated with oxygen, and usually closely predicts the arterial oxygen content. As such, it was particularly concerning when patients with severe COVID-19 requiring endotracheal intubation and mechanical ventilation within one of our intensive care units were observed to have significant discordance between their predicted arterial oxygen content via pulse oximetry and their actual measured oxygen content. We offer these preliminary observations along with our speculative causes as a timely, urgent clinical need. In the setting of a COVID-19 intensive care unit, entering a patient room to obtain a fresh arterial blood gas sample not only takes exponentially longer to do given the time required for donning and doffing of personal protective equipment (PPE), it involves the consumption of already sparce PPE, and it increases the risk of viral exposure to the nurse, physician, or respiratory therapist entering the room to obtain the sample. As such, technology similar to pulse oximetry which can be applied to a patients finger, and then continuously monitored from outside the room is essential in preventing a particularly dangerous situation of unrealized hypoxia in this critically-ill patient population. Additionally, it would appear that conventional two-wavelength pulse oximetry may not accurately predict the arterial oxygen content of blood in these patients. This discordance of oxygenation measurements poses a critical concern in the evaluation and management of the acute hypoxemic respiratory failure seen in patients with COVID-19.

Antithrombotic Agent Use in Elderly Patients Sustaining Low-Level Falls.

BACKGROUND: Elderly patients who are injured from a low-level fall comprise an increasing percentage of trauma admissions. We sought to evaluate the prevalence of antithrombotic (anticoagulant or antiplatelet) agent use, injury patterns, and outcomes in this population, focusing on intracranial hemorrhage (ICH). METHODS: We retrospectively reviewed the trauma registry at an American College of Surgeons-verified Level I trauma center for all patients aged 65 y or older admitted between 2007 and 2016 following a low-level fall. Medical records of patients on antithrombotic agents were examined in detail. Patients were divided into four groups based on the presence/absence of ICH and presence/absence of preadmission antithrombotic medication use. RESULTS: There were 4074 elderly patients admitted after a low-level fall, of which 1153 (28.3%) had a traumatic ICH, and 1238 (30.4%) were on antithrombotic agents. Notably, 35.9% of patients on antithrombotics had an ICH, as compared to 25.0% of 2836 patients not on antithrombotics other than aspirin (P < 0.001). The overall distribution of antithrombotic agent use differed significantly between the ICH and non-ICH groups; the ICH group had more coumadin usage. The mortality rate was significantly different across groups, with the group having ICH and a history of antithrombotics having the highest mortality at 14.2% (P < 0.001). Excluding the 27.8% of patients who were transferred into our hospital demonstrated that significantly more admissions on antithrombotics had ICH (22.4%) versus ICH admissions not on antithrombotics (14.7%, P < 0.001). The mortality rate was significantly different across groups, with the group having ICH and a history of antithrombotics having the highest mortality at 12.0% (P < 0.001). On multivariable analysis, anticoagulants, antiplatelets, and aspirin were all significantly associated with ICH; but only anticoagulants were significantly associated with mortality. CONCLUSIONS: Antithrombotic agent use was common in admitted elderly patients sustaining a low-level fall and is associated with an elevated rate of ICH. Anticoagulants were also associated with increased mortality.

Tracheobronchial Slough, a Potential Pathology in Endotracheal Tube Obstruction in Patients With Coronavirus Disease 2019 (COVID-19) in the Intensive Care Setting.

BACKGROUND: A novel coronavirus (COVID-19) erupted in the latter part of 2019. The virus, SARS-CoV-2 can cause a range of symptoms ranging from mild through fulminant respiratory failure. Approximately 25% of hospitalized patients require admission to the intensive care unit, with the majority of those requiring mechanical ventilation. High density consolidations in the bronchial tree and in the pulmonary parenchyma have been described in the advanced phase of the disease. We noted a subset of patients who had a sudden, significant increase in peak airway, plateau and peak inspiratory pressures. Partial or complete ETT occlusion was noted to be the culprit in the majority of these patients. METHODS: With institutional IRB approval, we examined a subset of our mechanically ventilated COVID-19 patients. All of the patients were admitted to one of our COVID-19 ICUs. Each was staffed by a board certified intensivist. During multidisciplinary rounds, all arterial blood gas (ABG) results, ventilator settings and ventilator measurements are discussed and addressed. ARDSNet Protocols are employed. In patients with confirmed acute occlusion of the endotracheal tube (ETT), acute elevation in peak airway and peak inspiratory pressures are noted in conjunction with desaturation. Data was collected retrospectively and demographics, ventilatory settings and ABG results were recorded. RESULTS: Our team has observed impeded ventilation in intubated patients who are several days into the critical course. Pathologic evaluation of the removed endotracheal tube contents from one of our patients demonstrated a specimen consistent with sloughed tracheobronchial tissues and inflammatory cells in a background of dense mucin. Of 110 patients admitted to our adult COVID-19 ICUs, 28 patients required urgent exchange of their ETT. CONCLUSION: Caregivers need to be aware of this pathological finding, recognize, and to treat this aspect of the COVID-19 critical illness course, which is becoming more prevalent.

A reference guide to rapidly implementing an institutional dashboard for resource allocation and oversight during COVID-19 pandemic surge.

OBJECTIVES: We develop a dashboard that leverages electronic health record (EHR) data to monitor intensive care unit patient status and ventilator utilization in the setting of the COVID-19 pandemic. MATERIALS AND METHODS: Data visualization software is used to display information from critical care data mart that extracts information from the EHR. A multidisciplinary collaborative led the development. RESULTS: The dashboard displays institution-level ventilator utilization details, as well as patient-level details such as ventilator settings, organ-system specific parameters, laboratory values, and infusions. DISCUSSION: Components of the dashboard were selected to facilitate the determination of resources and simultaneous assessment of multiple patients. Abnormal values are color coded. An overall illness assessment score is tracked daily to capture illness severity over time. CONCLUSION: This reference guide shares the architecture and sample reusable code to implement a robust, flexible, and scalable dashboard for monitoring ventilator utilization and illness severity in intensive care unit ventilated patients.

A pilot study assessing the spiritual, emotional, physical/environmental, and physiological needs of mechanically ventilated surgical intensive care unit patients via eye tracking devices, head nodding, and communication boards.

BACKGROUND: Mechanically ventilated patients in the intensive care unit (ICU) are unable to communicate verbally. We sought to evaluate their needs via a communication board (CB) and a novel eye tracking device (ETD) that verbalizes selections made by gazing. METHODS: This was a pilot prospective study conducted in a tertiary care surgical ICU. Continuously mechanically ventilated adult surgical ICU patients with a Richmond Agitation-Sedation Scale score of -1 to +1, without cognitive impairment, were eligible. We asked patients four yes-or-no questions to assess basic needs regarding presence of pain, need for endotracheal suction, satisfactory room temperature, and position comfort. Patients were then asked if there was anything else that they wanted to communicate. All responses were confirmed by head nodding. RESULTS: The median accuracy of the CB (100% (IQR 100%-100%)) for basic needs communication (yes/no questions) was comparable with that of the ETD (100% (IQR 68.8%-100%); p=0.14) in the 12 enrolled patients. Notably, 83% of patients desired to communicate additional information, ranging from spiritual (eg, desire for prayer/chaplain), emotional (eg, frustration, desire for comfort), physical/environmental (eg, television), to physiological (eg, thirst/hunger) needs. DISCUSSION: The majority of patients desired to communicate something other than basic needs. Unless specifically assessed via an assistive communication device (eg, CB or ETD), some of these other needs would have been difficult to discern. LEVEL OF EVIDENCE: IV therapeutic care/management.

Admission of elderly blunt thoracic trauma patients directly to the intensive care unit improves outcomes.

INTRODUCTION: Blunt thoracic trauma in the elderly has been associated with adverse outcomes. As an internal quality improvement initiative, direct intensive care unit (ICU) admission of nonmechanically ventilated elderly patients with clinically important thoracic trauma (primarily multiple rib fractures) was recommended. METHODS: A retrospective review of the trauma registry at a level 1 trauma center was performed for patients aged ≥65 y with blunt thoracic trauma, admitted between the 2 y before (2010-2012) and after (2013-2015) the recommendation. RESULTS: There were 258 elderly thoracic trauma admissions post-recommendation (POST) and 131 admissions pre-recommendation (PRE). Their median Injury Severity Score (13 versus 12, P = ns) was similar. The POST group had increased ICU utilization (54.3% versus 25.2%, P < 0.001). The POST group had decreased unplanned ICU admissions (8.5% versus 13.0%, P < 0.001), complications (14.3% versus 28.2%, P = 0.001), and ICU length of stay (4 versus 6 d, P = 0.05). More POST group patients were discharged to home (41.1% versus 27.5%, P = 0.008). Of these, the 140 POST and 33 PRE patients admitted to the ICU had comparable median Injury Severity Score (14 versus 17, P = ns) and chest Abbreviated Injury Score ≥3 (66.4% versus 60.6%, P = ns). The POST-ICU group redemonstrated the above benefits, as well as decreased hospital length of stay (10 versus 14 d, P = 0.03) and in-hospital mortality (2.9% versus 15.2%, P = 0.004). CONCLUSIONS: Admission of geriatric trauma patients with clinically important blunt thoracic trauma directly to the ICU was associated with improved outcomes.

Unplanned intensive care unit admission following trauma.

BACKGROUND: The prevalence and outcomes of trauma patients requiring an unplanned return to the intensive care unit (ICU) and those initially admitted to a step-down unit or floor and subsequently upgraded to the ICU, collectively termed unplanned ICU (UP-ICU) admission, are largely unknown. METHODS: A retrospective review of the trauma registry of a suburban regional trauma center was conducted for adult patients who were admitted between 2007 and 2013, focusing on patients requiring ICU admission. Prehospital or emergency department intubations and patients undergoing surgery immediately after emergency room evaluation were excluded. RESULTS: Of 5411 admissions, there were 212 UP-ICU admissions, 541 planned ICU (PL-ICU) admissions, and 4658 that were never admitted to the ICU (NO-ICU). Of the 212 UP-ICU admits, 19.8% were unplanned readmissions to the ICU. Injury Severity Score was significantly different between PL-ICU (16), UP-ICU (13), and NO-ICU (9) admits. UP-ICU patients had significantly more often major (Abbreviated Injury Score ≥ 3) head/neck injury (46.7%) and abdominal injury (9.0%) than the NO-ICU group (22.5%, 3.4%), but significantly less often head/neck (59.5%) and abdominal injuries (17.9%) than PL-ICU patients. Major chest injury in the UP-ICU group (27.8%) occurred at a statistically comparable rate to PL-ICU group (31.6%) but more often than the NO-ICU group (14.7%). UP-ICU patients also significantly more often underwent major neurosurgical (10.4% vs 0.7%), thoracic (0.9% vs 0.1%), and abdominal surgery (8.5% vs 0.4%) than NO-ICU patients. Meanwhile, the PL-ICU group had statistically comparable rates of neurosurgical (6.8%) and thoracic surgical (0.9%) procedures but lower major abdominal surgery rate (2.0%) than the UP-ICU group. UP-ICU admission occurred at a median of 2 days following admission. UP-ICU median hospital LOS (15 days), need for mechanical ventilation (50.9%), and in-hospital mortality (18.4%) were significantly higher than those in the PL-ICU (9 days, 13.9%, 5.4%) and NO-ICU (5 days, 0%, 0.5%) groups. CONCLUSIONS: UP-ICU admission, although infrequent, was associated with significantly greater hospital length of stay, rate of major abdominal surgery, need for mechanical ventilation, and mortality rates than PL-ICU and NO-ICU admission groups.

Clopidogrel-Associated Thrombotic Thrombocytopenic Purpura following Endovascular Treatment of Spontaneous Carotid Artery Dissection.

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening multisystem disease secondary to platelet aggregation. We present a patient who developed profound thrombocytopenia and anemia 8 days following initiation of therapy with clopidogrel after stent placement for carotid artery dissection. She did not have a disintegrin and metalloproteinase with thrombospondin domain 13 (ADAMTS 13) deficiency. Management included steroids and therapeutic plasma exchange. Clopidogrel has rarely been associated with TTP. Unlike other causes of acquired TTP, the diagnosis of early clopidogrel-associated TTP is largely clinical given the infrequent reduction in ADAMTS 13 activity.

Outcomes following prolonged mechanical ventilation: analysis of a countywide trauma registry.

BACKGROUND: The care of mechanically ventilated patients at high-volume centers in select nontrauma populations has variable effects on outcomes. We evaluated outcomes for trauma patients requiring prolonged mechanical ventilation (PMV). We further hypothesized that the higher mechanical ventilator volume trauma center would have better outcomes. METHODS: A retrospective review of a county's trauma registry was performed for trauma patients who were at least 18 years old admitted from 2006 to 2010. Eleven hospitals serve this suburban county, with a population of approximately 1.5 million people. The state has designated them as nontrauma centers (n = 6), area trauma centers (ATCs, n = 4), or regional trauma center (RTC, n = 1), where the last one provides the highest echelon of care. Patients requiring mechanical ventilation for at least 96 hours following injury were evaluated. RESULTS: A total of 3,382 trauma patients were admitted to the RTC, and 5,870 were admitted to the other 10 hospitals in the county. Seven hundred seventy-one received mechanical ventilation at the RTC, and 687 at the other 10 hospitals combined. Of these patients, 407 at the RTC and 308 at the remaining facilities (291 at ATCs and 17 at nontrauma centers) required PMV. Median (interquartile range [IQR]) Injury Severity Score (ISS) at the RTC was higher (29 [21-41] vs. 22 [16-29] p < 0.001) than that at ATCs. Hospital length of stay (in days) was comparable between the RTC and ATCs (28 [18-45] vs. 26 [16-44.7]). With regard to complications, rates of renal failure, sepsis, and myocardial infarction were similar. The RTC had higher pneumonia rates (59% vs. 45.4%, p < 0.001) and venous thromboembolic disease rates (20.4% vs. 10.4%, p < 0.001) than did ATCs. In-hospital mortality was 17% at the RTC and 34.4% at ATCs (p < 0.001). CONCLUSION: A mortality benefit but higher VTE and pneumonia rate for PMV patients at the RTC was noted. Collaborative practice initiatives are warranted to reduce morbidity and mortality across the region. LEVEL OF EVIDENCE: Epidemiologic study, level IV.

Surgical treatment of C2 fractures in the elderly: a multicenter retrospective analysis.

STUDY DESIGN: Multicenter retrospective analysis. OBJECTIVES: To review the results of surgical treatment during the last 6 years of C2 fractures in patients over the age of 70. SUMMARY OF BACKGROUND DATA: Little information exists about the clinical outcome of surgical treatment of elderly patients with C2 fractures, their ability to return to their previous environment, and their postoperative level of independence. METHODS: The medical records and radiographs of 29 patients who had undergone surgical treatment for C2 fractures were reviewed. The type of C2 fracture, neurologic examination at presentation, type of surgical treatment, perioperative morbidity and mortality, presence of osseous union, and stability of alignment were recorded. Long-term disposition was determined from office visits or by telephone interview. RESULTS: Twenty-four of 29 patients had type II dens fractures alone. The remaining 5 had associated C1 fractures. All patients were neurologically intact at presentation except for 2 patients with signs and symptoms of central cord syndrome. Perioperative complications occurred in 3 patients (10.3%). One patient died on postoperative day 6 from a myocardial infarction. Mean+/-SD radiographic follow-up was 9+/-3.2 months (range, 3 to 24). Of the 16 patients who underwent odontoid screw fixation, 6 (37.5%) had osseous union, and 9 (56.2%) were stable on radiographs. An additional patient who had odontoid screw initially required a posterior approach reoperation. Of the 13 posterior fusions, 4 (30.7%) had osseous unions and 9 (69.2%) were stable on flexion extension radiographs. Mean+/-SD clinical follow-up was 18+/-2.2 months (range, 3 to 72 mo). Twenty-five of 29 patients (86.2%) returned to their previous environment. Two patients died of unrelated etiology. CONCLUSIONS: C2 fractures in the elderly can be treated surgically with both anterior and posterior approaches with acceptable morbidity and mortality rates. The majority of patients can be mobilized early and return to their previous levels of independence.