Christopher T. Stephens

The Success of Emergency Endotracheal Intubation in Trauma Patients: A 10-Year Experience at a Major Adult Trauma Referral Center

BACKGROUND:Emergency airway management is a required skill for many anesthesiologists. We studied 10 yr of experience at a Level 1 trauma center to determine the outcomes of tracheal intubation attempts within the first 24 h of admission. METHODS:We examined Trauma Registry, quality management, and billing system records from July 1996 to June 2006 to determine the number of patients requiring intubation within 1 h of hospital arrival and to estimate the number requiring intubation with the first 24 h. We reviewed the medical record of each patient in either cohort who underwent a surgical airway access procedure (tracheotomy or cricothyrotomy) to determine the presenting characteristics of the patients and the reason they could not be orally or nasally intubated. RESULTS:All intubation attempts were supervised by an anesthesiologist experienced in trauma patient care. Rapid sequence intubation with direct laryngoscopy was the standard approach throughout the study period. During the first hour after admission, 6088 patients required intubation, of whom 21 (0.3%) received a surgical airway. During the first 24 h, 10 more patients, for a total of 31, received a surgical airway, during approximately 32,000 attempts (0.1%). Unanticipated difficult upper airway anatomy was the leading reason for a surgical airway. Four of the 31 patients died of their injuries but none as the result of failed intubation. CONCLUSIONS:In the hands of experienced anesthesiologists, rapid sequence intubation followed by direct laryngoscopy is a remarkably effective approach to emergency airway management. An algorithm designed around this approach can achieve very high levels of success.

Effects of fenoldopam, a dopamine D-1 agonist, and clevidipine, a calcium channel antagonist, in acute renal failure in anesthetized rats.

The present studies were conducted to: a) comparatively evaluate the effects of clevidipine, a new dihydropyridine calcium antagonist, and fenoldopam, a dopamine (D-1) receptor agonist on basal renal function, and b) to determine the efficacy of these agents in protecting renal function in an experimental model of ischemia/reperfusion (I/R) induced acute renal failure in rats. Infusions of either clevidipine or fenoldopam (5.0 nmol/kg−1 min−1 i.v. for 60 min) produced significant increases in urine flow (UV), urinary sodium excretion (UNaV), and fractional excretion of sodium (FENa) in inactin anesthetized rats. Unlike clevidipine, fenoldopam also produced significant increases in renal blood flow (RBF) and urinary potassium excretion (UKV). In a separate series, unilateral renal failure was induced in anesthetized rats by occluding the left renal artery for 40 min followed by reperfusion. In this model, there was a 70–75% reduction in the GFR that was paradoxically associated with several fold increases in UV, UNaV, and FENa in the vehicle treated group. In two separate groups, infusions of neither clevidipine nor fenoldopam (5.0 nmol/kg−1 min−1) for 60 min beginning 10 min before reperfusion, improved filtration fraction. However, clevidipine treatment markedly improved tubular function in that loss of sodium and water were significantly attenuated and UV and UNaV were restored towards basal levels. In contrast, in the fenoldopam group, tubular function was further deteriorated as evidenced by exacerbated losses of sodium and water. These observations suggest that whereas both clevidipine and fenoldopam were potent natriuretic agents, only the calcium antagonist was effective in preserving renal function in the present experimental model of ischemic renal failure.

Trauma-Associated bleeding: Management of massive transfusion

Purpose of review Early treatment goals in the bleeding trauma patient have changed based on recent research findings. Trauma patients requiring a massive transfusion protocol have shown a decreased mortality based on a more aggressive and balanced approach to blood product resuscitation. This chapter will review the recent advances in managing the bleeding trauma patient. Recent findings Recent data have suggested a combined approach of early ratio-based blood product use, bedside viscoelastic hemostatic assays, hemostatic resuscitation, and finally goal-directed therapy to complete resuscitation. Summary There is now evidence to support the early use of a 1 : 1 : 1 blood product transfusion protocol to restore lost circulating volume, improve oxygen carrying capacity, replace diluted platelets, and replenish clotting factors in massively bleeding trauma patients. Further study is needed to determine whether prehospital initiation of blood products and pharmacological adjuncts will improve outcomes.

Automated Prediction of Early Blood Transfusion and Mortality in Trauma Patients

BACKGROUND Prediction of blood transfusion needs and mortality for trauma patients in near real time is an unrealized goal. We hypothesized that analysis of pulse oximeter signals could predict blood transfusion and mortality as accurately as conventional vital signs (VSs). METHODS Continuous VS data were recorded for direct admission trauma patients with abnormal prehospital shock index (SI = heart rate [HR] / systolic blood pressure) greater than 0.62. Predictions of transfusion during the first 24 hours and in-hospital mortality using logistical regression models were compared with DeLong’s method for areas under receiver operating characteristic curves (AUROCs) to determine the optimal combinations of prehospital SI and HR, continuous photoplethysmographic (PPG), oxygen saturation (SpO2), and HR-related features. RESULTS We enrolled 556 patients; 37 received blood within 24 hours; 7 received more than 4 U of red blood cells in less than 4 hours or “massive transfusion” (MT); and 9 died. The first 15 minutes of VS signals, including prehospital HR plus continuous PPG, and SpO2 HR signal analysis best predicted transfusion at 1 hour to 3 hours, MT, and mortality (AUROC, 0.83; p < 0.03) and no differently (p = 0.32) from a model including blood pressure. Predictions of transfusion based on the first 15 minutes of data were no different using 30 minutes to 60 minutes of data collection. SI plus PPG and SpO2 signal analysis (AUROC, 0.82) predicted 1-hour to 3-hour transfusion, MT, and mortality no differently from pulse oximeter signals alone. CONCLUSION Pulse oximeter features collected in the first 15 minutes of our trauma patient resuscitation cohort, without user input, predicted early MT and mortality in the critical first hours of care better than the currently used VS such as combinations of HR and systolic blood pressure or prehospital SI alone. LEVEL OF EVIDENCE Therapeutic/prognostic study, level II.

Rupture of a Nonaneurysmal Aorta Secondary to Staphylococcus Aortitis A Case Report and Review of the Literature

Infectious aortitis has become increasingly uncommon and, when diagnosed, typically occurs in an immunocompromised elderly male with a history of Staphylococcus or Salmonella infection and underlying atheromatous cardiovascular disease. The authors report a case of a 74-year-old man with aortitis complicated by rupture secondary to Staphylococcus aureus infection. The patient presented with worsening abdominal pain and fever after being discharged from the emergency room 2 weeks before with back pain and leukocytosis diagnosed as urinary tract infection and bronchitis. Computed tomography (CT) imaging of the retroperitoneum on the first visit appeared normal. Repeat CT scan on the subsequent visit revealed a contained rupture of a nonaneurysmal aorta at the level of the diaphragm. The patient was taken to the operating room emergently for repair. An infected periaortic hematoma and a 1 cm perforation in the posterior aorta were found. The aorta was excised and the area debrided. Revascularization was performed using a 22 mm extruded polytetrafluoroethylene (ePTFE) interposition graft placed in situ. This case demonstrates that a high index of suspicion is required in diagnosing infectious aortitis and that the diagnosis may be delayed in many cases. Additionally, it may not be uncommon for the infected aorta to rupture without prior aneurysm formation.

Comparison of Decision-Assist and Clinical Judgment of Experts for Prediction of Lifesaving Interventions.

ABSTRACT Early recognition of hemorrhage during the initial resuscitation of injured patients is associated with improved survival in both civilian and military casualties. We tested a transfusion and lifesaving intervention (LSI) prediction algorithm in comparison with clinical judgment of expert trauma care providers. We collected 15 min of pulse oximeter photopletysmograph waveforms and extracted features to predict LSIs. We compared this with clinical judgment of LSIs by individual categories of prehospital providers, nurses, and physicians and a combined judgment of all three providers using the Area Under Receiver Operating Curve (AUROC). We obtained clinical judgment of need for LSI from 405 expert clinicians in135 trauma patients. The pulse oximeter algorithm predicted transfusion within 6 h (AUROC, 0.92; P < 0.003) more accurately than either physicians or prehospital providers and as accurately as nurses (AUROC, 0.76; P = 0.07). For prediction of surgical procedures, the algorithm was as accurate as the three categories of clinicians. For prediction of fluid bolus, the diagnostic algorithm (AUROC, 0.9) was significantly more accurate than prehospital providers (AUROC, 0.62; P = 0.02) and nurses (AUROC, 0.57; P = 0.04) and as accurate as physicians (AUROC, 0.71; P = 0.06). Prediction of intubation by the algorithm (AUROC, 0.92) was as accurate as each of the three categories of clinicians. The algorithm was more accurate (P < 0.03) for blood and fluid prediction than the combined clinical judgment of all three providers but no different from the clinicians in the prediction of surgery (P = 0.7) or intubation (P = 0.8). Automated analysis of 15 min of pulse oximeter waveforms predicts the need for LSIs during initial trauma resuscitation as accurately as judgment of expert trauma clinicians. For prediction of emergency transfusion and fluid bolus, pulse oximetry features were more accurate than these experts. Such automated decision support could assist resuscitation decisions, trauma team, and operating room and blood bank preparations.

Resuscitative Endovascular Balloon Occlusion of the Aorta: Principles, Initial Clinical Experience, and Considerations for the Anesthesiologist

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular technique that allows for temporary occlusion of the aorta in patients with severe, life-threatening, trauma-induced noncompressible hemorrhage arising below the diaphragm. REBOA utilizes a transfemoral balloon catheter inserted in a retrograde fashion into the aorta to provide inflow control and support blood pressure until definitive hemostasis can be achieved. Initial retrospective and registry clinical data in the trauma surgical literature demonstrate improvement in systolic blood pressure with balloon inflation and improved survival compared to open aortic cross-clamping via resuscitative thoracotomy. However, there are no significant reports of anesthetic implications and perioperative management in this challenging cohort. In this narrative, we review the principles, technique, and logistics of REBOA deployment, as well as initial clinical outcome data from our level-1 American College of Surgeons–verified trauma center. For anesthesiologists who may not yet be familiar with REBOA, we make several suggestions and recommendations for intraoperative management based on extrapolation from these initial surgical-based reports, opinions from a team with increasing experience, and translated experience from emergency aortic vascular surgical procedures. Further prospective data will be necessary to conclusively guide anesthetic management, especially as potential complications and implications for global organ function, including cerebral and renal, are recognized and described.

Vascular and extravascular volume expansion of dobutamine and norepinephrine in normovolemic sheep

In low-flow states, such as circulatory shock, both fluids and catecholamines are often coadministered. We have previously found that adrenergic agents alter volume expansion after a fluid bolus. The present study tested the volume expansion properties of dobutamine and norepinephrine in sheep treated with (series 1) and without (series 2) a fluid bolus. Series 1 (n = 6 per group): no drug (control), dobutamine (10 &mgr;g · kg−1 · min−1), or norepinephrine (1.0 &mgr;g · kg−1 · min−1) was begun 30 min before a 24-mL · kg−1, 20-min, 0.9% NaCl bolus. The effect of drug and fluid on plasma volume (&Dgr;PV), urinary output (UOP), and extravascular volume (&Dgr;EVV) was determined. Series 2: Identical protocol but no fluid bolus. Series 1: the fluid bolus resulted in a peak and sustained &Dgr;PV expansion. Norepinephrine (7.5 ± 0.9 mL · kg−1) and dobutamine (9.5 ± 1.1 mL · kg−1) significantly increased &Dgr;PV compared with control (3.8 ± 1.1 mL · kg−1). Cumulative UOP was reduced by dobutamine (3.8 ± 1.4 mL · kg−1) compared with norepinephrine (25.1 ± 3.9 mL · kg−1) and control (16.9 ± 4.0 mL · kg−1). Norepinephrine increased &Dgr;PV, while reducing &Dgr;EVV after bolus. Series 2: &Dgr;PV was unchanged in the control group. Dobutamine and norepinephrine increased &Dgr;PV over time, 5.1 ± 0.5 and 4.0 ± 0.5 mL · kg−1, respectively. At study end, UOP was lowest in dobutamine. Norepinephrine resulted in loss of &Dgr;EVV fluid. data suggest a novel role for adrenergic receptors in regulating vascular and EVV expansion. &bgr;-Adrenergic agonists enhance vascular volume expansion, whereas &agr;-adrenergic agonists eliminate extravascular fluid.

Airway Management in Cardiac Arrest

Airway management has been emphasized as crucial to effective resuscitation of patients in cardiac arrest. However, recent research has shown that coronary and cerebral perfusion should be prioritized rather than airway management. Endotracheal intubation has been deemphasized. This article reviews the current state of the literature regarding airway management of the patient in cardiac arrest. Ventilatory management strategies are also discussed.

Anesthetic Considerations Utilizing Resuscitative Endovascular Balloon Occlusion of the Aorta in the Hemorrhaging Trauma Patient

Purpose of reviewThe purpose of this manuscript was to review and discuss the new and emerging technique of resuscitative endovascular balloon occlusion (REBOA) in the management of the hemorrhaging trauma patient.Recent findingsResuscitative endovascular balloon occlusion of the aorta (REBOA) offers a new alternative for the management of non-compressible hemorrhage. Anesthesiology can be central in managing these patients from preoperative assessment upon admission, to definitive care or damage control surgery in the operating room and onward care in the critical care unit.SummaryThe anesthesiologist should not only have the necessary knowledge and appreciation for the use of REBOA in the resuscitative process but also an understanding of its effects on physiology.