Metabolic acidosis and the role of unmeasured anions in critical illness and injury.

Acid-base disorders are frequently present in critically ill patients. Metabolic acidosis is associated with increased mortality, but it is unclear whether as a marker of the severity of the disease process or as a direct effector. The understanding of the metabolic component of acid-base derangements has evolved over time, and several theories and models for precise quantification and interpretation have been postulated during the last century. Unmeasured anions are the footprints of dissociated fixed acids and may be responsible for a significant component of metabolic acidosis. Their nature, origin, and prognostic value are incompletely understood. This review provides a historical overview of how the understanding of the metabolic component of acid-base disorders has evolved over time and describes the theoretical models and their corresponding tools applicable to clinical practice, with an emphasis on the role of unmeasured anions in general and several specific settings.

Palliative Care in a Pandemic: A Multicenter Cohort of Critically Ill Patients with Coronavirus Disease 2019.

Background: Trends in mortality, palliative care, and end-of-life care among critically ill patients with coronavirus disease 2019 (COVID-19) remain underreported. We hypothesized that use of palliative care and end-of-life care would increase over time, because improved understanding of the disease course and prognosis would potentially lead to more frequent use of these services. Patients and Methods: Adult patients with severe acute respiratory syndrome coronavirus 2 infection (SARS-CoV-2) during pandemic wave one (W1: March 2020 to September 2020) or wave two (W2: October 2020 to June 2021) admitted to an intensive care unit (ICU) in one of six northeastern U.S. hospitals were identified and clinical characteristics obtained. Vaccination data were unavailable. Outcomes of interest included mortality, palliative care consultation, and any end-of-life care (including hospice and comfort care). Results: There were 1,904 critically ill patients with COVID-19: 817 (42.9%) in W1 and 1,087 (57.1%) in W2. Patients received mechanical ventilation more often during W1 than W2 (52.9% vs. 46.3%; p = 0.004), with no difference in ICU or hospital length of stay between waves. Mortality between W1 and W2 was similar (31.2% vs. 30.9%; p = 0.888). There was no difference in use of palliative care or any end-of-life care between waves. Patients who died during W2 versus W1 were more likely to have received both mechanical ventilation (77.1% vs. 67.1%; p = 0.007) and palliative care services (52.1% vs. 41.2%; p = 0.009). However, logistic regression adjusted for demographics, baseline comorbid disease, and clinical characteristics showed no difference in mortality (odds ratio [OR], 1.15; 95% confidence interval [CI], 0.89-1.48), palliative care (OR, 1.08; 95% CI, 0.84-1.40), or any end-of-life care (OR, 1.05; 95% CI, 0.82-1.34) in W2 versus W1. Conclusions: Mortality among critically ill patients with COVID-19 has remained constant across two pandemic waves with no change in use of palliative or end-of-life care.

Evaluation of mild cognitive impairment and dementia in patients with metastatic renal cell carcinoma.

BACKGROUND: Dementia and cancer are both more common in adults as they age. As new cancer treatments become more popular, it is important to consider how these treatments might affect older patients. This study evaluates metastatic renal cell carcinoma (mRCC) as a risk factor for older adults developing mild cognitive impairment or dementia (MCI/D) and the impact of mRCC-directed therapies on the development of MCI/D. METHODS: We identified patients diagnosed with mRCC in a Surveillance, Epidemiology, and End Results (SEER)-Medicare dataset from 2007 to 2015 and matched them to non-cancer controls. Exclusion criteria included age < 65 years at mRCC diagnosis and diagnosis of MCI/D within the year preceding mRCC diagnosis. The main outcome was time to incident MCI/D within one year of mRCC diagnosis for cases or cohort entry for non-cancer controls. Cox proportional hazards models were used to measure associations between mRCC and incident MCI/D as well as associations of oral anticancer agent (OAA) use with MCI/D development within the mRCC group. RESULTS: Patients with mRCC (n = 2533) were matched to non-cancer controls (n = 7027). mRCC (hazard ratio [HR] 8.52, p < .001), being older (HR 1.05 per 1-year age increase, p < .001), and identifying as Black (HR 1.92, p = .047) were predictive of developing MCI/D. In addition, neither those initiating treatment with OAAs nor those who underwent nephrectomy were more likely to develop MCI/D. CONCLUSIONS: Patients with mRCC were more likely to develop MCI/D than those without mRCC. The medical and surgical therapies evaluated were not associated with increased incidence of MCI/D. The increased incidence of MCI/D in older adults with mRCC may be the result of the pathology itself or risk factors common to the two disease processes.

Perioperative glycemic management in 2011: paradigm shifts.

PURPOSE OF REVIEW: The publication of Van den Berghe's landmark study in 2001 supported the use of intensive insulin therapy (IIT) to target normoglycemia in the critically ill and triggered a new era in glycemic management in the perioperative period and in the ICU. In 2009, the normoglycemia in intensive care evaluation-survival using glucose algorithm regulation (NICE-SUGAR) trial demonstrated increased mortality and incidence of hypoglycemia in patients managed with IIT, resulting in a shift toward higher blood glucose targets in this patient population. This review distills clinically pertinent principles from the related literature published in the months since the NICE-SUGAR trial. RECENT FINDINGS: A target blood glucose level in the acute care setting supported by many of the pertinent societies and frequently quoted in the literature is 140-180 mg/dl. Hyperglycemia, hypoglycemia, and glucose variability are detrimental. Accurate and efficient glucose monitoring devices are essential. Insulin infusion protocols (IIPs) employed to achieve desired blood glucose targets must be individualized and validated for the ICU and institution in which they are being implemented. SUMMARY: Appropriate glycemic management in the acute care setting can be achieved by targeting a reasonable blood glucose range and employing specific and institutionally validated IIPs.

Risk of venous thromboembolism after spinal cord injury: not all levels are the same.

BACKGROUND: Venous thromboembolism (VTE), a diagnosis that includes both deep vein thrombosis and pulmonary embolism, is a well-recognized complication following injury. Previous studies have identified multiple risk factors including spinal cord injury (SCI). We hypothesized that the level of SCI also influences the likelihood of VTE. METHODS: The National Trauma Data Bank was queried to identify all patients with SCI admitted in 2007 and 2008. Rates of VTE, demographics, admitting comorbidities, in-hospital complications, level of SCI (divided by National Trauma Data Bank into five groups), associated injuries, and outcome variables were abstracted. Multiple regression was used to identify independent risk factors for VTE. RESULTS: During the 2-year period, 18,302 patients were admitted with SCI. The overall rate of VTE was 4.3% but varied significantly depending on the level of SCI injury (χ(2), 44.8; p < 0.05). Patients with high cervical spine (C1-4) injury had a rate VTE of 3.4%, whereas patients with high thoracic spine (T1-6) injury had the highest rate of VTE at 6.3%. The lowest rate of VTE was in patients with lumbar injury (3.2%). There were no significant differences in the preexisting comorbidities or in-hospital complications among the five SCI groups with the exception of pneumonia. In a multiple logistic regression model, the level of SCI was an independent risk factor for VTE as was increasing age, increasing Injury Severity Score, male gender, traumatic brain injury, and chest trauma. CONCLUSIONS: The rate of VTE differs with various SCI levels. Patients with high thoracic (T1-6) injury seem to be at the highest risk and patients with high cervical (C1-4) injury at one of the lowest. A higher index of suspicion for VTE should therefore be maintained in patients with a high thoracic SCI. Further studies are required to elucidate the underlying mechanisms.

The status of massive transfusion protocols in United States trauma centers: massive transfusion or massive confusion?

BACKGROUND: Massive transfusion protocol (MTP) utilization and makeup is unknown. STUDY DESIGN AND METHODS: A Web-based survey was sent to members of the Eastern Association for the Surgery of Trauma and published in the American Association for the Surgery of Trauma newsletter. Comparisons were made with chi-square and logistic regression. RESULTS: A total of 186 surgeons and 59 center directors responded. To avoid bias, directors' responses are reported. Sixty percent annually admit more than 1500 patients. Sixty-seven percent had in-house attending coverage and 85% had a MTP. Presence of a MTP was not predicted by institution size, level, residency status, or admissions. Sixty-five percent of MTPs had been in place less than 5 years with 18% less than 1 year. Designs varied: 23% had one batch of components, 25% had two or three, 41% had more than three, and 11% did not use batches. Only 62% of first batches contained fresh-frozen plasma (FFP). In the second batch 98% had FFP. All third boxes had FFP. A ratio of FFP : red blood cells (RBCs) of less than 1 in the first batch predicted a ratio less than 1 in the second batch (p = 0.013). Twenty-seven percent had blood stored in the emergency department and 14% in the operating room. Twenty-four percent of MTPs autoactivate and 80% are trauma surgeon activated, 66% by the anesthesia staff, 32% by other surgeons, and 17% by the blood bank. Trauma surgeons activate the MTP most. CONCLUSION: Most centers have a MTP. Protocols are variable and new, and half have a 1:1 FFP : RBC ratio. Protocols with fewer initial units of FFP compared to RBCs maintain this.

Contrast-induced nephropathy in elderly trauma patients.

BACKGROUND: Computed tomography (CT) is the gold standard for the identification of occult injuries, but the intravenous (IV) contrast used in CT scans is potentially nephrotoxic. Because elderly patients have decreased renal function secondary to aging and chronic disease, we sought to determine the rate of acute kidney injury (AKI) in elderly trauma patients exposed to IV contrast. METHODS: Medical records of patients older than 55 years evaluated at a level-one trauma center between January 2003 and July 2008 were reviewed. Contrast was nonionic, isosmolar, and administered in standard volumes. Groups were based on administration of contrast. AKI was defined as a 25% relative or 0.5 mg/dL absolute increase in serum creatinine within 72 hours of presentation [corrected]. RESULTS: During the study period 1,371 patients older than 55 years were evaluated, and 1,152 met the inclusion criteria. CT was performed on 1,071 patients (96%); 71% of this group received IV contrast. There was no significant difference between the contrast and noncontrast groups in terms of baseline characteristics. Criteria for AKI were satisfied in 2.1% of all patients, including 1.9% the contrast group versus 2.4% in the noncontrast group. AKI diagnosed within 72 hours of patient presentation was an independent risk factor for in-hospital mortality and prolonged length of stay. CONCLUSIONS: IV contrast media in elderly trauma patients is not associated with an increased risk of AKI. Development of AKI within 72 hours of admission is associated with mortality and increased length of stay.

Resident Education in End-of-Life Communication and Management: Assessing Comfort Level to Enhance Competence and Confidence.

OBJECTIVES: Our primary objective was to understand residents' baseline comfort with end-of-life (EOL) communication and management and to compare this with their comfort after completion of their surgical intensive care unit (SICU) rotation. We also evaluated the association between prior training with perceived level of comfort with EOL issues, and whether the resident believed in the concept of a "better death." DESIGN, SETTING, PARTICIPANTS: As a quality improvement initiative, we conducted surveys of trainees before and after their rotation in the Yale New Haven Hospital SICU. Prerotation and postrotation surveys were administered to all residents who rotated during the 2016-2017 academic year and the first half of 2017-2018. The survey consisted of 34 questions querying residents on their level of training in EOL care, their comfort with management and discussions in different EOL domains, and their beliefs about what measures would have improved their ability to provide EOL care. Residents surveyed were from general surgery, emergency medicine, or anesthesia departments. RESULTS AND CONCLUSIONS: Our study demonstrates that there is a significant correlation between resident comfort with EOL communication and experience providing EOL care. However, concepts in medicolegal aspects of palliative care could be taught through formal didactics, and structured training may allow residents the opportunity to reflect on the importance of a "better death."

Uncovering system errors using a rapid response team: cross-coverage caught in the crossfire.

BACKGROUND: Because of the 80-hour work week, extensive service cross-coverage creates great potential for patient care errors. These patient care emergencies are increasingly managed using a rapid response team (RRT) to reduce patient morbidity. We examine the proximate causes of a surgical RRT activation. We hypothesize that most RRTs would occur during cross-coverage hours and be preventable or potentially preventable. METHODS: All surgical RRTs more than a 15-month period were captured using a nursing database and the note from the staffing intensivist/fellow. RRTs were reviewed for appropriateness (pre-existing criteria) and proximate cause. Proximate causes were further classified as patient disease, team error, nursing error, or system error as well as preventable, potentially preventable, or nonpreventable. RESULTS: Of 98 RRT activations, complete data were available for 82 (84%); 100% met activation criteria; and 76 (93%) occurred between 2100 and 0600. Seventy-six patients were 48 hours to 72 hours postoperative; six had nonoperatively managed injuries. The most common reason for activation was impending respiratory failure and acute volume overload (n = 72; 88%). RRT therapies included diuretics (n = 72), antiarrhythmics (n = 48), oxygen (n = 82), and bronchodilators (n = 36); only 2 received blood component therapy. Seventy-eight patients (95%) were transferred to higher level of care (61, surgical intensive care unit; 17, SSDU). Only 46% of patients required intubation. Performance improvement review identified 90% of physician related RRTs as preventable/potentially preventable because of errors in judgment or omission. Four RRTs because of patient disease were unpreventable. Two potentially preventable errors were each ascribed to RN or system concerns. CONCLUSION: RRT activations principally result from team-based errors of omission, more often occur between 2100 and 0600, and are more often preventable or potentially preventable. Careful attention to fluid balance and medications for comorbid diseases would reduce RRT needs.

Evaluation of Swallow Function Post-Extubation: Is It Necessary to Wait 24 Hours?

BACKGROUND: Post-extubation dysphagia is associated with an increased incidence of nosocomial pneumonias, longer hospitalizations, and higher re-intubation rates. The purpose of this study was to determine if it is necessary to delay swallow evaluation for 24 hours post-extubation. METHODS: A prospective investigation of swallowing was conducted at 1, 4, and 24 hours post-extubation to determine if it is necessary to delay swallow evaluation following intubation. Participants were 202 adults from 5 different intensive care units (ICU). RESULTS: A total of 166 of 202 (82.2%) passed the Yale Swallow Protocol at 1 hour post-extubation, with an additional 11 (177/202; 87.6%) at 4 hours, and 8 more (185/202; 91.6%) at 24 hours. Only intubation duration ≥4 days was significantly associated with nonfunctional swallowing. CONCLUSIONS: We found it is not necessary to delay assessment of swallowing in individuals who are post-extubation. Specifically, the majority of patients in our study (82.2%) passed a swallow screening at 1 hour post-extubation.

Surgical Critical Care for the Trauma Patient with Cardiac Disease.

The elderly population is rapidly increasing in number. Therefore, geriatric trauma is becoming more prevalent. All practitioners caring for geriatric trauma patients should be familiar with the structural and functional changes naturally occurring in the aging heart, as well as common preexisting cardiac diseases in the geriatric population. Identification of the shock state related to cardiac dysfunction and targeted assessment of perfusion and resuscitation are important when managing elderly patients. Finally, management of cardiac dysfunction in the trauma patient includes an appreciation of the inherent effects of trauma on cardiac function.

Utilization and impact on fellowship training of non-physician advanced practice providers in intensive care units of academic medical centers: a survey of critical care program directors.

BACKGROUND: Non-physician advanced practice providers (APPs) such as nurse practitioners and physician assistants are being increasingly utilized as critical care providers in the United States. The objectives of this study were to determine the utilization of APPs in the intensive care units (ICU)s of academic medical centers (AMCs) and to assess the perceptions of critical care fellowship program directors (PDs) regarding the impact of these APPs on fellowship training. METHODS: A cross-sectional national survey questionnaire was distributed to program directors of 331 adult Accreditation Council for Graduate Medical Education-approved critical care fellowship training programs (internal medicine, anesthesiology and surgery) in US AMCs. RESULTS: We received 124 (37.5%) PD responses. Of these, 81 (65%) respondents indicated that an APP was part of the care team in either the primary ICU or any ICU in which the fellow trained. The majority of respondents reported that patient care was positively affected by APPs with nearly two-thirds of PDs reporting that fellowship training was also positively impacted. CONCLUSIONS: Our survey revealed that APPs are utilized in a large number of US AMCs with critical care training programs. Program director respondents believed that patient care and fellowship training were positively impacted by APPs.

When the ICU is the operating room.

BACKGROUND: The surgical intensive care unit (SICU) is increasingly used as a surrogate operating room (OR). This study seeks to characterize a Level I trauma center's operative undertakings in the SICU versus OR for trauma and emergency general surgery patients. METHODS: Operative and ICU databases were queried for all operative procedures as a function of procedure type (CPT code) and location (OR, ICU) from August 2002 through June 2009. Mode of ventilation, type of anesthesia used, and adverse outcomes were recorded. Data were divided into 2002-2006 versus 2007-2009 because of MD staffing and service structure changes. Time frames were compared via Student's t-test or χ(2) as appropriate; significance for p < 0.05 (*) versus 2002-2006. RESULTS: Trauma service-admitted patient volume increased from 2002-2003 (n = 1,293) to 2006-2007 (n = 1,577) and again in 2008-2009 (n = 1,825). Emergency general surgery total operative cases increased from 2002-2003 (n = 246) to 2005-2006 (n = 468). Case volume further increased in 2006-2007 (n = 767*), 2007-2008 (n = 1,071*), and 2008-2009 (n = 875*) compared with 2002-2003 or 2005-2006. Relaparotomy and temporary abdominal closure procedures were significantly increased in 2007-2008 (n = 109*) and 2008-2009 (n = 128*) versus 2002-2006 (n = 6) and 2006-2007 (n = 10). ICU cases were 11.5% of total cases (OR + ICU) spanning 2002-2006 and significantly increased to 24.3%* in 2007-2008 and 36%* in 2008-2009. Advanced ventilation was used in 15% of ICU cases in 2002-2003 and significantly increased to 40% in 2006-2007 and 78%* in 2008-2009. Neuromuscular blockade was rare; most cases (93.9%) were performed under deep sedation. CONCLUSION: Our ICU is increasingly used for surgical procedures traditionally reserved for the OR. Advanced ventilation management may influence the choice of operative location. The ICU may be safely used as an operative location for the critically ill and injured. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Disseminated enteroinvasive aspergillosis in a critically ill patient without severe immunocompromise.

Invasive aspergillosis (IA) is a rapidly progressive and often fatal infectious disease described classically in patients who are highly immunocompromised. However, there has been increasing evidence that IA may affect critically ill patients without traditional risk factors. We present a case of a 47-year-old man without conventional risk factors for IA who presented with impending sepsis and proceeded to have a complicated hospital course with a postmortem diagnosis of invasive gastrointestinal aspergillosis of the small bowel.

Compared to conventional ventilation, airway pressure release ventilation may increase ventilator days in trauma patients.

BACKGROUND: Airway pressure release ventilation (APRV) is used both as a rescue therapy for patients with acute lung injury and as a primary mode of ventilation. Unlike assist-control volume (ACV) ventilation that uses spontaneous breathing trials, APRV weaning consists of gradual decreases in supporting pressure. We hypothesized that the APRV weaning process increases total ventilator days compared with those of spontaneous breathing trials-based weaning. METHODS: A retrospective review of a Level I trauma center's database identified trauma admissions from January 1, 2007, to December 31, 2010, which required mechanical ventilation for more than 24 hours and survived. Demographics, injuries, in-hospital complications, ventilation mode(s), and total ventilator days were abstracted. RESULTS: A total of 362 patients fulfilled study entry criteria; 53 patients with more than one ventilator mode change were excluded. Seventy-five patients were successfully liberated from mechanical ventilation on APRV and 234 on ACV. The APRV and ACV groups, respectively, were similar in age (46.1 vs. 44.6 years) and sex (72% vs. 73% male) but differed in Injury Severity Score (20.8 vs. 17.5; p = 0.03). Patients on APRV had higher rates of abdominal compartment syndrome (6.7% vs. 0.8%, p = 0.003) and were more likely to have a higher chest Abbreviated Injury Scale (AIS) score ≥3 (57.3% vs. 30.8%, p < 0.001). Ventilator days were significantly greater in the APRV group (19.6 vs. 10.7 days, p < 0.001). Multiple regression was performed to adjust for the clinical differences between the two groups, identifying APRV as an independent predictor for increased number of ventilator days (B = 6.2 ± 1.5, p < 0.001) in addition to male sex, abdomen AIS score of 3 or higher, spine AIS score of 3 or higher, acute renal failure, and sepsis. CONCLUSION: APRV is frequently used for patients who are more severely injured or who develop in-hospital complications such as pneumonia. However, after controlling for potential confounding factors in a multiple regression model, the APRV mode itself seems to increase ventilator days.