Hippo ERCast May 2021

Watch and Wait for Pneumothorax

Large primary spontaneous pneumothorax does not always require a chest tube. In clinically stable patients, conservative management with observation can avoid intervention for many, while supplemental oxygen appears to accelerate pleural air resorption, especially in larger pneumothoraces. Conservative Management of Spontaneous Pneumothorax Stable large PSP: A hemodynamically stable patient with a large primary spontaneous pneumothorax may be managed without immediate tube thoracostomy, shifting the problem from automatic drainage to careful selection and observation. Observation first strategy: In the NEJM trial, moderate-to-large primary spontaneous pneumothorax was randomized to observation versus intervention, and conservative care still achieved 94% radiographic resolution by 8 weeks. Need for rescue intervention: Observation was not purely passive: 15% of conservatively managed patients ultimately needed a procedure, most often for intolerable symptoms or abnormal physiology. Follow-up feasibility: Conservative management depends on a system that can provide repeat imaging, reassessment, and rapid escalation if the patient worsens. We get into the practical selection issues in the episode. Tube size reframing: The usual debate over pigtail versus standard chest tube misses the bigger question in some stable patients: whether any pleural intervention is needed up front. Oxygen and Pneumothorax Resolution Oxygen aided resorption: Supplemental oxygen increases the rate of pneumothorax absorption by steepening the nitrogen gradient, making pleural air reabsorb faster than on room air. Headline effect size: A classic study found the mean absorption rate increased about fourfold during high-flow oxygen therapy, with the biggest apparent benefit in larger pneumothoraces. Older evidence base: The oxygen data come mainly from small older studies rather than large modern randomized trials, so the physiologic rationale is stronger than the trial literature. Selective oxygen use: In the conservative-management trial, oxygen was not given routinely; it was reserved for patients with oxygen saturation below 92%, an important distinction from reflex high-flow use.

Lit Matters #1 - Single vs Serial Troponin in ED Chest Pain

Low-risk ED chest pain can often be ruled out without prolonged observation. In community emergency departments using a conventional troponin assay, a single negative troponin paired with HEART score risk stratification had the same 30-day rate of myocardial infarction or cardiac death as serial testing. Single vs Serial Troponin HEART-guided discharge strategy: A low-risk HEART score was the key companion to a single negative conventional troponin, framing this as selective risk stratification rather than a shortcut. Matched 30-day safety signal: Thirty-day myocardial infarction or cardiac mortality after ED discharge was 0.4% in both the single-troponin and serial-troponin groups. Conventional assay relevance: These results came from a contemporary conventional troponin-I assay, making the question especially relevant to departments not using high-sensitivity troponin. Low yield of repeat testing: Only 66 patients in the serial-testing cohort had a subsequent positive troponin, suggesting the second draw changed management infrequently. We get into the practice implications in the episode. Timing caveat: Symptom-onset timing was not available in the dataset, an important limitation because early presenters are the group most likely to benefit from serial sampling.

SCAD - Spontaneous Coronary Artery Dissection

Spontaneous coronary artery dissection is an underrecognized cause of acute coronary syndrome, especially in younger women and during pregnancy or the postpartum period. SCAD often presents like routine ACS despite a normal first troponin or nonspecific ECG, and its management diverges sharply from thrombotic MI once the diagnosis is made. Recognizing SCAD in Acute Coronary Syndrome Young women with ACS: SCAD accounts for up to 25% of acute coronary syndrome in women 50 and younger, making it a crucial diagnosis when chest pain seems out of proportion to the usual risk profile. Normal first troponin: About 20% of patients have an initially negative troponin and a low HEART score, so serial biomarkers matter when the story still sounds ischemic. We get into that diagnostic tension in the episode. Subtle ECG findings: ECGs may be normal or show only nonspecific ST-T changes, although roughly half of SCAD patients present with STEMI and pregnancy-associated cases tend to involve more proximal LAD lesions. Stress and recurrence pattern: Female sex, pregnancy or postpartum state, and intense emotional or physical stress are classic clues, and prior SCAD meaningfully raises the risk of recurrence. Intramural hematoma phenotype: Most SCAD cases are not a visible intimal flap but an intramural hematoma, which is why intracoronary imaging with OCT or IVUS may be needed to confirm the diagnosis. Management Differences From Thrombotic MI Conservative healing trajectory: Eighty to ninety percent of affected coronary arteries heal completely with conservative management, so stable patients with preserved flow are often observed rather than stented. Fragile vessel intervention: PCI is harder in SCAD because the vessels are fragile and dissections can extend; early propagation occurs in about 10%, which is part of why inpatient observation matters. Avoid routine thrombolysis: Thrombolytics can worsen an intramural hematoma, making lytics a poor fit when SCAD is the true mechanism of infarction. Stop heparin after diagnosis: Once SCAD is confirmed, heparin can usually be discontinued because intracoronary thrombus is uncommon and ongoing anticoagulation may add harm. Selective secondary prevention: Beta-blockers are associated with fewer recurrences, whereas statins are not routine unless there is a separate indication like severe hyperlipidemia. We walk through the practical medication distinctions in the chapter. Persistent post infarct pain: Recurrent chest pain after SCAD is often vasospastic rather than a new infarction, and long-acting nitrates or calcium channel blockers can help even when repeat ED workups are negative. Associated Arteriopathy and Follow Up Systemic vascular disease signal: Sixty to eighty percent of SCAD patients have an underlying arteriopathy, most commonly fibromuscular dysplasia, with potential aneurysm or dissection elsewhere in the body. Brain to pelvis imaging: After recovery, screening CT angiography from brain to pelvis is recommended to look for extracoronary vascular abnormalities that change counseling and follow-up. Cardiac rehab role: Cardiac rehab is especially valuable because many patients are young, previously healthy, and psychologically shaken after being initially dismissed or misread in the ED. Pregnancy associated severity: Pregnancy-related SCAD more often involves proximal coronary segments, larger infarcts, and worse outcomes than nonpregnancy SCAD.

Lit Matters #2 - The Canadian TIA Score vs ABCD2/ABCD2i

Transient ischemic attack is a time-sensitive stroke warning, but not all TIA risk scores separate low-risk patients well enough to guide disposition. The Canadian TIA Score outperformed ABCD2 and ABCD2i in suspected TIA, with the real-world value hinging on local access to rapid imaging and neurology follow-up. TIA Risk Stratification Canadian score performance: The Canadian TIA Score provided better 7-day stroke discrimination than ABCD2 or ABCD2i, with an AUC of 0.70 versus 0.60 and 0.64. Useful low-risk group: Unlike ABCD2 and ABCD2i, the Canadian score identified a genuinely low-risk cohort, classifying 16.3% of patients into a group with a 7-day event rate at or below 0.5%. Middle-category problem: ABCD2 and ABCD2i pushed nearly everyone into a medium-risk bucket, leaving only 3% to 7% outside that zone and limiting bedside usefulness for disposition decisions. Risk range across scores: The Canadian TIA Score spans from -3 to 23 and maps to a graded 7-day stroke risk from 0.01% up to 28%. We get into when that granularity actually changes management in the episode. System-dependent disposition: Risk stratification only helps if rapid MRI or vascular imaging and neurology follow-up are available within 24 to 48 hours; otherwise, admission for expedited workup may be the safer path.

Septic Bursitis

Septic bursitis usually arises in chronically inflamed superficial bursae after skin inoculation, while deeper bursae are more often seeded hematogenously. The key bedside challenge is separating septic bursitis from aseptic bursitis and from septic arthritis, then deciding when aspiration actually helps. Diagnosing and Managing Septic Bursitis Typical pathogens and hosts: Staphylococcus aureus causes about 80% of septic bursitis, usually in patients with chronic bursitis, repetitive microtrauma, diabetes, gout, rheumatoid arthritis, or immunocompromise. Superficial versus deep spread: Prepatellar and olecranon bursae are usually infected from the skin, whereas iliopsoas and subacromial bursae more often reflect hematogenous spread, a distinction that matters clinically. Bedside clues to infection: Redness and swelling alone do not prove infection, but fever, malaise, and a warmer bursa than surrounding skin raise concern; one study found a surface temperature difference over 2.2 C highly predictive. Separating bursa from joint: Pain with passive range of motion, axial loading, or tenderness through the full arc points toward septic arthritis rather than isolated bursitis; ultrasound helps localize the effusion. We get into the ultrasound distinctions in the episode. Aspiration through erythema: Unlike arthrocentesis, overlying erythema is not necessarily a contraindication to bursal aspiration if a fluid collection is present, and ultrasound guidance can support a safer longer-track approach. Fluid testing and treatment debate: Bursal WBC counts above 2000 cells/µL, PMN predominance, low glucose, and a positive Gram stain support septic bursitis, but whether uncomplicated cases need aspiration before antibiotics remains unsettled. We walk through that management controversy in the chapter.

Lit Matters #3 - MENDS2 - Propofol vs Dexmedetomidine

In mechanically ventilated adults with sepsis, dexmedetomidine did not outperform propofol on delirium-free days, ventilator-free days, or 90-day mortality. The practical signal for ICU sedation is that either agent is reasonable when light sedation is the target and opioids are doing much of the work. Sepsis Vent Sedation Trial Neutral primary outcomes: Delirium- and coma-free days were essentially identical at about 10.7 versus 10.8 days, reinforcing that dexmedetomidine was not clinically superior to propofol in this sepsis cohort. No ventilator benefit: Ventilator-free days were also the same at roughly 24 days, arguing against a meaningful liberation advantage for dexmedetomidine in mechanically ventilated septic adults. Similar mortality signal: Ninety-day mortality was nearly superimposable at 38% versus 39%, making any survival advantage unlikely and leaving sedative choice largely a matter of context and preference. Light sedation target: Both groups spent only about 60% of time at the intended RASS target, a reminder that protocolized sedation often underdelivers even in a blinded ICU trial. We get into why that matters in the episode. Tiny study drug doses: Median doses were strikingly low at 0.27 mcg/kg/hr for dexmedetomidine and about 10 mcg/kg/min for propofol, which limits broad claims about either drug at more aggressive dosing. Opioid-heavy rescue strategy: Fentanyl was the main rescue agent rather than another sedative, with median rates around 60 mcg/hr, suggesting the comparison was really sedative choice layered onto substantial opioid exposure.

A Philosophical Approach to Pediatric Analgesia

Pediatric pain is consistently undertreated in the ED, despite evidence that repeated painful stimuli can lead to hyperalgesia and allodynia. A practical approach starts with multimodal analgesia, treating the underlying condition, and delivering meds by the least painful route possible. Principles of pediatric analgesia Undertreated pediatric pain: Children with clearly painful conditions receive analgesia less often than adults; in one fracture review, 53% of children were treated versus 73% of adults, underscoring a persistent ED care gap. Pain memory consequences: Repeated painful stimuli in children can amplify future pain responses, with hyperalgesia and allodynia as the key long-term concern rather than a brief procedural upset. Three-part analgesia framework: The core strategy is multimodal analgesia, treatment of the underlying pathology, and choosing the least painful route first, a bedside mindset shift we lay out in the episode. Assume pain in nonverbal kids: If an injury or procedure would hurt a verbal patient, treat the nonverbal child as if it hurts too; under-recognition is a bigger error than overcalling pain in this setting. Avoid unnecessary procedures: Nasogastric tubes and catheterized samples can be among the most painful interventions, so the better analgesic move is often deciding not to do a low-yield procedure at all. Medication choices and routes Morphine over codeine: Morphine is the preferred opioid because it is active as given, while codeine is a prodrug with CYP2D6 variability that led to an FDA black box warning in patients under 18. Headline morphine dosing: A practical starting dose for morphine is 0.1 mg/kg, then titrate to comfort rather than stopping at a token first dose. Intranasal fentanyl role: Intranasal fentanyl can provide meaningful pain relief in about 10 to 15 minutes, making it especially useful when you expect a single-dose analgesic plan. Route-specific drug performance: Intranasal delivery is not interchangeable across agents; fentanyl performs well, ketamine is erratic, and oral midazolam is often better tolerated despite a slower onset. We get into the route nuances in the chapter. Multimodal nonopioid backbone: Acetaminophen and ibuprofen should anchor many plans, with escalation to morphine, ketamine, or a nerve block when the injury and severity justify it. Procedural pain and distress reduction Sucrose is not analgesia: Oral sucrose may reduce distress, but it has not been shown to provide analgesia in patients able to report pain, so it should not replace proven pain control. Topical anesthetic timing: Topical anesthetic only helps if you give it enough time to work; rushing the procedure is a common reason otherwise good local pain control fails. Infant LP local anesthesia: Infants do need local anesthetic for lumbar puncture; EMLA and careful lidocaine infiltration with the smallest practical needle make the procedure less traumatic. Lidocaine with epinephrine: For lumbar puncture anesthesia, lidocaine with epinephrine may lower the risk of a traumatic tap, a small technical pearl with outsized procedural payoff. Distress modulation tools: Covering the child’s eyes, using videos or music, and reframing equipment with child-friendly language can meaningfully reduce distress alongside analgesics. We share the bedside phrasing in the episode.