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Identifying patients at imminent risk of death is critical in the management of trauma patients. This study measures the vital sign thresholds associated with death among trauma patients.
Methods:
This study included data from patients ≥15 years of age in the American College of Surgeons Trauma Quality Improvement Program (TQIP) database. Patients with vital signs of zero were excluded. Documented prehospital and emergency department (ED) vital signs included systolic pressure, heart rate, respiratory rate, and calculated shock index (SI). The area under the receiver operator curves (AUROC) was used to assess the accuracy of these variables for predicting 24-hour survival. Optimal thresholds to predict mortality were identified using Youden’s Index, 90% specificity, and 90% sensitivity. Additional analyses examined patients 70+ years of age.
Results:
There were 1,439,221 subjects in the 2019-2020 datasets that met inclusion for this analysis with <0.1% (10,270) who died within 24 hours. The optimal threshold for prehospital systolic pressure was 110, pulse rate was 110, SI was 0.9, and respiratory rate was 15. The optimal threshold for the ED systolic was 112, pulse rate was 107, SI was 0.9, and respiratory rate was 21. Among the elderly sub-analysis, the optimal threshold for prehospital systolic was 116, pulse rate was 100, SI was 0.8, and respiratory rate was 21. The optimal threshold for ED systolic was 121, pulse rate was 95, SI was 0.8, and respiratory rate was 21.
Conclusions:
Systolic blood pressure (SBP) and SI offered the best predictor of mortality among trauma patients. The SBP values predictive of mortality were significantly higher than the traditional 90mmHg threshold. This dataset highlights the need for better methods to guide resuscitation as initial vital signs have limited accuracy in predicting subsequent mortality.
In the United States, all 50 states and the District of Columbia have Good Samaritan Laws (GSLs). Designed to encourage bystanders to aid at the scene of an emergency, GSLs generally limit the risk of civil tort liability if the care is rendered in good faith. Nation-wide, a leading cause of preventable death is uncontrolled external hemorrhage. Public bleeding control initiatives aim to train the public to recognize life-threatening external bleeding, perform life-sustaining interventions (including direct pressure, tourniquet application, and wound packing), and to promote access to bleeding control equipment to ensure a rapid response from bystanders.
Methods:
This study sought to identify the GSLs in each state and the District of Columbia to identify what type of responder is covered by the law (eg, all laypersons, only trained individuals, or only licensed health care providers) and if bleeding control is explicitly included or excluded in their Good Samaritan coverage.
Results:
Good Samaritan Laws providing civil liability qualified immunity were identified in all 50 states and the District of Columbia. One state, Oklahoma, specifically includes bleeding control in its GSLs. Six states – Connecticut, Illinois, Kansas, Kentucky, Michigan, and Missouri – have laws that define those covered under Good Samaritan immunity, generally limiting protection to individuals trained in a standard first aid or resuscitation course or health care clinicians. No state explicitly excludes bleeding control from their GSLs, and one state expressly includes it.
Conclusion:
Nation-wide across the United States, most states have broad bystander coverage within GSLs for emergency medical conditions of all types, including bleeding emergencies, and no state explicitly excludes bleeding control interventions. Some states restrict coverage to those health care personnel or bystanders who have completed a specific training program. Opportunity exists for additional research into those states whose GSLs may not be inclusive of bleeding control interventions.
Hematological disorders are a heterogeneous group that may be inherited or acquired. During pregnancy the condition may improve, stabilize, or deteriorate due to normal physiological changes. Major risks in women are hemorrhage or thrombosis; inherited conditions may affect fetus as well. A multidisciplinary team is required to manage the pregnancy, delivery, and postpartum. This chapter reviews and summarizes the literature on maternal and fetal outcomes with a focus on anesthetic considerations and publications.
Thrombotic microangiopathies (TMA) are a group of conditions characterized by excessive platelet activation, resulting in microvascular thrombi and platelet consumption (thrombocytopenia). The thrombosed microvasculature shears red blood cells (RBCs), causing microangiopathic hemolytic anemia. Primary TMAs include thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS), while secondary TMAs result from infection, pregnancy, malignancy, drugs and toxins, among other causes.
TMAs do not directly involve the coagulation cascade, and therefore do not prolong coagulation studies. Microthrombi may result in ischemic complications in any organ system.
Severe pelvic fractures are a major cause of morbidity and mortality in trauma patients. As hemorrhage is the main cause of mortality in pelvic trauma, it is critical to assess hemodynamic stability and identify ongoing bleeding in the chest, abdomen and long bones. If no clear source of hemorrhage is identified and a patient remains unstable, suspicion for primary pelvic hemorrhage should be high. Suspect pelvic fracture in all cases of serious or multisystem trauma patients.
In pelvic trauma, there is a high incidence of associated injuries; therefore, special attention should be paid to the rectal and urogenital examinations. The most commonly used classification system for pelvic fractures is the Young–Burgess system. This system categorizes injuries on the basis of mechanism of injury and can be used to predict the risk of blood loss.
Optimal initial management of the trauma patient during the first several hours after injury offers the best chance of a good outcome. Patient management consists of rapid primary survey, resuscitation of vital functions, a more detailed secondary assessment, diagnostic tests to ascertain the extent of traumatic injury and finally, the initiation of definitive care.
Uncontrolled trauma-related hemorrhage remains the primary preventable cause of death among those with critical injury.
Study Objective:
The purpose of this investigation was to evaluate the types of trauma associated with critical injury and trauma-related hemorrhage, and to determine the time to definitive care among patients treated at major trauma centers who were predicted to require massive transfusion.
Methods:
A secondary analysis was performed of the Pragmatic, Randomized, Optimal Platelet and Plasma Ratios (PROPPR) trial data (N = 680). All patients included were predicted to require massive transfusion and admitted to one of 12 North American trauma centers. Descriptive statistics were used to characterize patients, including demographics, type and mechanism of injury, source of bleeding, and receipt of prehospital interventions. Patient time to definitive care was determined using the time from activation of emergency services to responder arrival on scene, and time from scene departure to emergency department (ED) arrival. Each interval was calculated and then summed for a total time to definitive care.
Results:
Patients were primarily white (63.8%), male (80.3%), with a median age of 34 (IQR 24-51) years. Roughly one-half of patients experienced blunt (49.0%) versus penetrating (48.2%) injury. The most common types of blunt trauma were motor vehicle injuries (83.5%), followed by falls (9.3%), other (3.6%), assaults (1.8%), and incidents due to machinery (1.8%). The most common types of penetrating injuries were gunshot wounds (72.3%), stabbings (24.1%), other (2.1%), and impalements (1.5%). One-third of patients (34.5%) required some prehospital intervention, including intubation (77.4%), chest or needle decompression (18.8%), tourniquet (18.4%), and cardiopulmonary resuscitation (CPR; 5.6%). Sources of bleeding included the abdomen (44.3%), chest (20.4%), limb/extremity (18.2%), pelvis (11.4%), and other (5.7%). Patients waited for a median of six (IQR4-10) minutes for emergency responders to arrive at the scene of injury and traveled a median of 27 (IQR 19-42) minutes to an ED. Time to definitive care was a median of 57 (IQR 44-77) minutes, with a range of 12-232 minutes. Twenty-four-hour mortality was 15% (n = 100) with 81 patients dying due to exsanguination or hemorrhage.
Conclusion:
Patients who experience critical injury may experience lengthy times to receipt of definitive care and may benefit from bystander action for hemorrhage control to improve patient outcomes.
The Stop the Bleed campaign provided civilians with tourniquet application training and increased the demand for tourniquets among the general population, which led to the development of new commercially available devices. However, most widely available tourniquets have not undergone testing by regulatory bodies and their efficacy remains unknown.
Study Objective:
This study aimed to compare the efficacy and performance of Combat Application Tourniquets (CAT) versus uncertified tourniquets.
Methods:
This study compared 25 CAT with 50 commercially available “look-alike” tourniquets (LA-TQ) resembling the CAT. The CAT and the LA-TQ were compared for cost, size, and tested during one-hour and six-hour applications on a manikin’s leg. The outcomes were force applied, force variation during the application, and tourniquet rupture rate.
Results:
The LA-TQ were cheaper (US$6.07 versus US$27.19), shorter, and had higher inter-device variability than the CAT (90.1 [SE = 0.5] cm versus 94.5 [SE = 0.1] cm; P <.001). The CAT applied a significantly greater force during the initial application when compared to the LA-TQ (65 [SE = 3] N versus 14 [SE = 1] N; P <.001). While the initial application force was maintained for up to six hours in both groups, the CAT group applied an increased force during one-hour applications (group effect: F [1,73] = 105.65; P <.001) and during six-hour applications (group effect: F [1,12] = 9.79; P = .009). The rupture rate differed between the CAT and the LA-TQ (0% versus 4%).
Conclusion:
The LA-TQ applied a significantly lower force and had a higher rupture rate compared to the CAT, potentially affecting tourniquet performance in the context of public bleeding control. These findings warrant increased layperson education within the framework of the Stop the Bleed campaign and further investigations on the effectiveness of uncertified devices in real-world applications.
Hemorrhage control prior to shock onset is increasingly recognized as a time-critical intervention. Although tourniquets (TQs) have been demonstrated to save lives, less is known about the physiologic parameters underlying successful TQ application beyond palpation of distal pulses. The current study directly visualized distal arterial occlusion via ultrasonography and measured associated pressure and contact force.
Methods:
Fifteen tactical officers participated as live models for the study. Arterial occlusion was performed using a standard adult blood pressure (BP) cuff and a Combat Application Tourniquet Generation 7 (CAT7) TQ, applied sequentially to the left mid-bicep. Arterial flow cessation was determined by radial artery palpation and brachial artery pulsed wave doppler ultrasound (US) evaluation. Steady state maximal generated force was measured using a thin-film force sensor.
Results:
The mean (95% CI) systolic blood pressure (SBP) required to occlude palpable distal pulse was 112.9mmHg (109-117); contact force was 23.8N [Newton] (22.0-25.6). Arterial flow was visible via US in 100% of subjects despite lack of palpable pulse. The mean (95% CI) SBP and contact force to eliminate US flow were 132mmHg (127-137) and 27.7N (25.1-30.3). The mean (95% CI) number of windlass turns to eliminate a palpable pulse was 1.3 (1.0-1.6) while 1.6 (1.2-1.9) turns were required to eliminate US flow.
Conclusions:
Loss of distal radial pulse does not indicate lack of arterial flow distal to upper extremity TQ. On average, an additional one-quarter windlass turn was required to eliminate distal flow. Blood pressure and force measurements derived in this study may provide data to guide future TQ designs and inexpensive, physiologically accurate TQ training models.
Major haemorrhage is a rare complication after chemoradiotherapy for oropharyngeal squamous cell carcinoma. This is managed by interventional neuroradiology with endovascular embolisation of the bleeding vessel. This study aimed to describe radiological and clinical predictors of haemorrhage.
Methods
A retrospective case series was conducted of all patients with oropharyngeal squamous cell carcinomas who suffered a major haemorrhage requiring embolisation during or after treatment with chemoradiotherapy or radiotherapy alone, between 2013 and 2021, in Western Australia.
Results
This study included 14 patients, in two groups: haemorrhage group (n = 70) and tumour stage matched non-haemorrhage group (n = 7). Patients who haemorrhaged had a larger average transverse axial tumour size on pre-treatment computed tomography (38 mm vs 22 mm; p = 0.02) and tumours tended to involve the proximal aspect of the offending bleeding vessel. All patients who haemorrhaged developed deep cavitating or ulcerative tumour bed changes on post-treatment imaging (p < 0.0001).
Conclusion
Tumour bed ulceration or cavitation appears to be highly predictive of haemorrhage in this patient cohort.
This study aimed to determine the efficacy of probiotic gargles compared with placebo gargles on reducing post-tonsillectomy morbidity in adults.
Method
This was a triple-blind, randomised, controlled trial and feasibility study. Thirty adults underwent elective tonsillectomy and were randomly assigned to receive either probiotic or placebo gargles for 14 days after surgery. Daily pain scores and requirement of analgesia were measured for 14 days post-operatively. Secondary outcomes assessed probiotic safety and tolerability and the feasibility of the trial.
Results
The probiotic group experienced less pain at rest on day 2. However, the amount of oxycodone (5 mg) tablets used was greater in the probiotic group compared with placebo. There were no statistically significant differences in the frequency of adverse effects between both groups. This trial was feasible.
Conclusion
This pilot study suggested that probiotic gargles do not reduce post-tonsillectomy pain or bleeding, highlighting the importance of pilot and feasibility studies in clinical research.
A 28-year-old gravida 3, para 2, last menstrual period eight weeks ago, presents for confirmation of pregnancy. She reports mild nausea and fatigue. She has regular menses and reports that she and her partner have been trying to conceive. Her obstetric history is significant for a full-term cesarean delivery for malpresentation and a first-trimester abortion requiring dilation and curettage. She has no past medical history. She is currently taking prenatal vitamins and she is allergic to penicillin.
A 28-year-old female para 0, non-smoker, presents to discuss management of adenocarcinoma in situ (AIS) on colposcopic biopsy. She has been in a mutually monogamous relationship for the past four years, has had two lifetime partners, and uses combined oral contraceptive pills (COCs; ethinyl estradiol 20 mcg/norethindrone 1 mg PO daily) for contraception. She has no past surgical history and no known drug allergies. She had a normal wellness examination three months ago and completed the HPV vaccination series at age 26. Her past medical history is significant for abnormal Pap smear. Her cervical cancer screening history is as follows:
A 34-year-old gravida 3, para 3 is undergoing an interval bilateral salpingectomy for permanent sterilization. She is currently using combined oral contraceptive pills (containing ethinyl estradiol/norethindrone) for contraception. Because of side effects associated with the pill, she has opted for permanent sterilization. She understands sterilization is a permanent procedure and is certain she has completed her family. Her pre-procedure pregnancy test was negative. All her deliveries were spontaneous vaginal deliveries. She has no history of easy bleeding or bruising. She has no past medical or surgical history. She is not taking any other medications and she has no known drug allergies.
A 35-year-old gravida 3, para 2, last menstrual period 11 weeks ago, presents with an undesired pregnancy. Her prior pregnancies were uncomplicated vaginal deliveries. Her ultrasound confirms an 11-week intrauterine pregnancy. She has no relevant past medical or surgical history. She is currently taking prenatal vitamins and has no known drug allergies. After counseling, she chooses to proceed with a surgical abortion. After the administration of 200 mg of oral doxycycline, a suction dilation and curettage (D&C) is performed under moderate sedation. After the procedure, she has persistent heavy vaginal bleeding.
A 30-year-old female, gravida1, para 0, presents to the office for a suction dilation and curettage (D&C) for management of a six-week missed abortion. Transvaginal ultrasound diagnosed the missed abortion one week ago and it was reconfirmed three days ago. She is taking ibuprofen 400 mg PO q 4 hours PRN and took diazepam 5 mg PO × 1 before arriving. She has no past medical or surgical history and no known drug allergies. On bimanual examination, a small, retroflexed uterus is noted. The cervix is stenotic, but dilation was able to be performed. Near the end of the procedure, the suction cannula passes without resistance deeper than expected. The patient describes a sudden increase in her pain. The procedure is stopped.
Sacrococcygeal teratoma (SCT) is a common tumor of the neonatal period. Prenatal diagnosis of SCT carries a high mortality rate because of the potential for high output heart failure and hydrops. Tumors can also rupture, leading to severe anemia and death. The mother’s health is also at risk if maternal mirror syndrome develops. Prenatal evaluation includes high resolution ultrasound, fetal echocardiography, and magnetic resonance imaging. Pregnancy management includes frequent assessment of the tumor size, growth, and the effects on the fetal cardiovascular system. Treatment options depend on the tumor characteristics and cardiac function, as well as maternal health and support. Fetal therapy aims to debulk or devascularize the tumor, thereby alleviating high output failure and minimizing the risk of spontaneous rupture and hemorrhage. Decisions regarding a symptomatic fetus with SCT may include prenatal intervention or early delivery. Anesthetic management of fetal treatment for SCT is tailored to the mode of therapy chosen; this may include a minimally invasive approach, in-utero surgery, or an EXIT procedure. The nuances of management of this condition center on understanding of the pathophysiology of a hydropic fetus as a result of the SCT and being prepared for resultant cardiovascular instability and massive hemorrhage.
Hemolytic disease of the fetus and newborn is a common cause of intrauterine death and increased neonatal morbidity. While this condition may occur as a result of maternal antibody formation to a variety of different antibodies,(alloimmunization), that which occurs in response to the Rhesus D antigen is the most common. Many centers now perform intrauterine fetal blood transfusion, a required mode of therapy for alloimunization, which is necessary to prevent fetal demise. The ability to accurately detect and treat fetuses affected by this condition depends on adequate prenatal care, astute maternal-fetal practitioners, and a robust center with the ability to analyze fetal blood samples which directs transfusion therapy. While intrauterine therapy is not without complications, and is commonly characterized by repeated fetal transfusions, the ability to transfuse fetuses in-utero has drastically improved the prognosis for affected babies.