Grand Rounds Recap 12.16.20
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MORBIDITY AND MORTALITY WITH DR. MAND
Case 1: Calcium channel blocker (CCB) overdose
CCB overdose
Two different classes:
Dihydropyridine are more selective for vascular calcium channels and Include amlodipine, felodipine, nicardipine, nifedipine, nimodipine
Non-dihydropyridine are more selective for cardiac calcium channels and include verapamil, diltiazem
If asymptomatic:
Activated charcoal if patient presents early after a toxic calcium channel blocker ingestion
Observe for 24 hours on telemetry due to risk of delayed absorption
If symptomatic:
IV calcium, goal serum level 12-14
IV fluids
Norepinephrine/epinephrine
High dose insulin
Plasmapheresis/Plasma exchange may be of value given that amlodipine is highly protein bound
Hyperinsulinemic-Euglycemic therapy
Effects:
Potent inotrope: Augments calcium processing myocardium
Improves intracellular energy utilization by using glucose over free fatty acids
Peripheral vasodilator by enhancing NO synthase activity
Literature is not robust, predominantly based on animal studies and case reports. However, it should be started quickly when the patient begins to develop hypotension.
Dose is high at 1U/kg IV bolus + 1U/kg/hr infusion, titrating up to 10U/kg/hr. Use concentrated infusions to reduce risk of volume overload.
Increased risk of hypoglycemic events, both glucose and potassium need adequate initial repletion and close monitoring
Case 2: Chemical Restraint in the Elderly & Verbal Orders
Chemical restraint in the elderly
Decreased renal clearance; drugs that are renally cleared include risperidone, midazolam
Decreased hepatic metabolism; drugs that are hepatically cleared include haloperidol, olanzapine, risperidone, ziprasidone
Decreased muscle mass leads to lower total body water content and increase in fat content, which impacts drug distribution
Hydrophilic drugs i.e. opiates: higher plasma concentration leading to overmedication/toxicity
Lipophilic drugs i.e. antipsychotics, benzodiazepines: higher body distribution leading to longer therapeutic duration
Beers Criteria is a resource to improve safety of prescription
Verbal orders in medicine
Best practices include:
Minimize verbal orders
Confirm patient and allergies
Assess medical history and vitals if feasible
Avoid abbreviations of medications
Request verbal readback
If ordering medication on someone else’s patient (reserved for emergencies only), confirm what has already been done for the patient
Case 3: Steroids in COVID-19
Recovery Trial NEJM Jul 2020
P: Hospitalized adults (>18 yo) who had clinically suspected or confirmed COVID infection (89%), without absolute contraindications to therapy were treated with dexamethasone at time of randomization
I: Dexamethasone 6 mg/day (oral or IV) up to 10 days + standard of care (N =2104)
C: Standard of care (N = 4321)
O: Primary outcome was 28 day mortality
Case 4: Venous thromboembolic disease in COVID-19
Pathophysiology
Endothelial injury from viral attachment to angiotensin-2 receptor of endothelial cells
Pro-inflammatory cytokines such as IL-6, IL-7 increasing fibrinogen production
Platelet activation, immobilization, mechanical ventilation
Literature review
Malas et al, E Clinical Medicine, 2020. Meta-analysis of 42 studies, N = 8271 patients.
21% VTE overall
14% PE overall, 19% PE in ICU
OR 1.74 morality if VTE with COVID
Watchmaker et al, Acad Emerg Med, 2020. Retrospective review, comparison of CTPA positive studies from 2019 to 2020 in NYC.
Acute PE prevalence has increased to 18.8% from 7.6% compared to pre-pandemic times
Associated unilateral leg swelling decreased 26% to 9%
Franco-Moreno et al, J Ultrasound Med, 2020. Prospective observational study, N = 26 patients in Spain.
7.7% DVT
Median peak D-dimer higher at 2.5 ug/mL
Summary
Higher prevalence of VTE, including PE, in COVID-19 patients
Preliminary studies demonstrate thrombotic > embolic phenomenon
A higher D-dimer cutoff is likely needed for PE risk stratification in these patients
Well’s criteria and PERC cannot rule out PE in the setting of COVID-19, but Well’s can still be used to determine a high underlying risk of PE
Strongly consider PE in patients with critical illness or baseline PE risk factors
Case 5: Spontaneous versus secondary bacterial peritonitis
Spontaneous bacterial peritonitis
Secondary to gut translocation into ascitic fluid in the setting of a weakened immune system from decreased production of complement and opsonin
Most commonly from E coli, Klebsiella, and Streptococcus
Occurs in 10-30% of patients with cirrhosis; 25% in-hospital mortality
Secondary bacterial peritonitis
Secondary to perforated viscus or infected abdominal organ
Most commonly polymicrobial or from Staphylococcus, E coli, or other gram negative rod
Morganella bacteremia is most commonly from biliary pathology (49%)
Occurs in 4.5% of all peritonitis; 60-80% in-hospital morality
Having 2 of 3 Runyon’s criteria increases suspicion of secondary bacterial peritonitis:
Total protein >1g/dL
Glucose < 50 mg/dL
LDH > serum upper limit of normal
+/- polymicrobial culture
In a retrospective cohort study of 130 patients, Runyon’s criteria + CT /US detected 21/22 secondary infections with no false positives in the spontaneous bacterial peritonitis group
Obtain CT imaging if critical illness, focal or concerning abdominal exam, or concerning lab abnormalities
Case 6: Unexpected Precipitous Delivery & Premature Birth
Precipitous Delivery in the ED
Prep yourself
Call for help: Extra hands are needed going from 1 patient to 2, preferably OB and pediatrics if available
Call for equipment:
Delivery: Sterile gloves, sterile towels, scissors, umbilical cord clamps, sterile 4x4 gauze, a needle driver, and sutures
Neonate: Neonatal warmer, neonatal resuscitation equipment
Brief history: gestational age, complications, how many infants
Confirm presenting part with ultrasound
Neonatal Resuscitation
NRP is useful but can be hard to remember in the heat of the moment
Golden minute: Neonates are most likely to respond to interventions in the first minute of life
Stimulate, position, warm
Respiratory compromise or HR < 100: If not apneic but labored breathing/cyanotic, supplemental oxygen +/- PPV including CPAP
After the first minute, if still not improving, focus on airway management and move to CPR and IV epinephrine if HR < 60 bpm
GLOBAL HEALTH GRAND ROUNDS: APPROACH TO FEVER IN THE TROPICS WITH GUEST LECTURER DR. COLLINS
Case 1: Fever & Headache in Guatemala
7 year old male presenting with fever and headache for a day. Associated with rash. No known immediate exposures, tick bites, or zoonotic exposure. It's the rainy season but there is no malaria risk. Up to date on immunizations. VS T 39C, HR 120, RR 24, BP 100/70. Exam notably for mild abdominal tenderness without peritoneal signs.
DDx: Common viral illness (Influenza etc); Arboviruses i.e. arthropod-borne viruses (Dengue, Chikungunya); Typhoid, Leptospirosis; Malaria
Testing: CBC, malaria smear or rapid diagnostic test, tourniquet test (i.e. capillary fragility in Dengue, performed by using BP cuff between diastolic and systolic pressure for 5 minutes looking for >=20 petechiae in a 1 inch square), renal/liver panel
Treatment of Dengue Fever: Fluids, supportive care, acetaminophen, avoid NSAIDS, repeat CBC every 1-2 days to follow thrombocytopenia, can progress to dengue shock syndrome from bleeding, caution in the critical phase (days 5-7) to ensure hydration
Chikungunya = Dengue-type presentation + arthritis. Not a hemorrhagic disease making NSAIDs acceptable, which are needed due to severe Chik pain.
Case 2: Fever & Epistaxis in Afghanistan
Crimean-Congo Hemorrhagic Fever
Don’t sweat it if you feel overwhelmed; use real time resources such as ArboNET, HealthMap, etc.
Consider local causes early i.e. What would a local provider think this is? CDC Yellowbook is particularly useful.
Run through the Taxonomic differential diagnosis of fever
Case 3: Fever & Abdominal Pain in Thailand
33 year old male presenting with fever and abdominal pain for 3 days, along with intermittent fever for 3 weeks, watery diarrhea, vomiting, and headache. Not the rainy season and no recent causes of mosquito-borne febrile illness. VS T 100.6, SBP 90. Exam notable for altered mental status, acute abdomen, and loss of liver dullness. Upright abdominal XR showed free air under the diaphragm.
Typhoid/Enteric Fever
Caused by Salmonella enterica, fecal-oral spread
Classic triad = fever, HA, GI symptoms; can have “rose spots” (feint on white skin); relative bradycardia
Intentional invasion which can lead to perforation or spontaneous resolution in 3-4 weeks
Diagnosis is bone marrow culture as gold standard but Typhoid has sens 96%/spec 90%; CBC classically showed leukopenia
Treatment is 3rd generation cephalosporin
Case 4: Fever & Headache in Philippines
23 year old female presenting with fever, mild headache, and myalgias for 4 days. It's the rainy season and her farm fields are flooded. VS T 39C. Exam notably for tire appearance and conjunctivitis. Presentation suggestive of Leptospirosis, but the key learning point is narrow your differential diagnosis by acuity of fever and WBC.
Case 5: Fever & Headache in Cambodia
Malaria
Caused by Plasmodium sp, falciparum is the top killer
Spread by the Anopheles species, a night feeder which is why bed nets are effective
Incubation is 7-30 days with paroxysmal fevers being classic
Diagnosis is via thick and thin smears. If there is high suspicion, antimalarials should not be discontinued until there are 3 negative thick and thin smears.
Key point: If you don’t know what you’re treating, cover with malaria treatment, 3rd generation cephalosporin, and doxycycline (which is often forgotten)
Case 6: Fever & Eosinophilia in Tanzania
Schistosomiasis: Eosinophilia should clue you into a parasitic disease
Case 7: Fever & Ulcer in Kenya
17 year old male presenting with 5 days of low grade fever and enlarging scalp lesion with heaped up border. This is classic for cutaneous anthrax, caused by Bacillus anthracis. Key point: Frame the fever in the context of other symptoms, such as diarrhea (malaria), rash (dengue, typhoid), eschar (anthrax), conjunctivitis (leptospirosis), relative bradycardia (dengue, typhoid, rickettsiae).
AIR CARE GRAND ROUNDS WITH DRS. GOTTULA, SKROBUT, MAKINEN, & HINCKLEY
Hamilton T-1 Military Vent
Air Care will be changing over to a new vent, potentially launching as early as January; stay tuned for more details
Pulmonary Physiology
Compliance: Increased compliance = increased expandability and decreased pressure
Resistance: Flow is approximately equal to 1/resistance (1/radius to the fourth power), thus a small radius = high resistance and low flow
VQ mismatching: 1) Shunt from malfunctioning alveolus, which creates an oxygenation problem; 2) Malfunctioning capillary causing dead space, which creates a ventilation problem
Vent Basics
Ventilation (Minute ventilation = TV x RR)
Tidal volume (TV): Volume in/out of the lungs, set based on volume or inspiratory pressure
Respiratory rate (RR): 1) Max spontaneous RR > mechanical RR because of breath stacking (passive > active respiration) and limitations of flow; 2) decreased returns at increased ventilator RR due to mechanical dead space; 3) I:E ratio
Oxygenation
FIO2
PEEP: Keeps alveoli open, helps with recruitment
Modes
Volume Control (VC): Volume is the independent variable. Pros = consistent tidal volume with guaranteed minute ventilation; Cons = constant inspiratory flow which is not physiologic, decreasing patient tolerance
Pressure Control (PC): Pressure is the independent variable. Pros = Decelerating inspiratory flow; Cons = variable tidal volume
Adaptive Support Ventilation (ASV): Set minute ventilation, volume-targeted pressure-controlled mode via automatic adjustment of PIP, RR, and I:E
Case 1: 28M DM1 who ran out of his insulin, actively being treated for DKA but appears to be tiring out. Gas shows: pH 7.05/pCO2 32/HCO3 8. Using Winter’s formula, this demonstrates a primary metabolic acidosis with a secondary respiratory acidosis. While you normally would try to prevent mechanical ventilation if at all possible, this gas puts you in a force to act situation. When deciding an intubation method, consider BIPAP as a bridge and an awake intubation to minimize apneic time. After intubating, pay careful attention to minute ventilation to address the patient’s acid-base derangements.
Case 2: A female patient with asthma ran out of medications and got intubated for respiratory failure. During transport, incomplete exhilaration and high airway pressure alarms are going off despite being on continuous albuterol. Initial ABG 7.27/pCO2 54, pO2 282, HCO3 24. Flow curves show incomplete exhalation, i.e. auto-peeping. Consider a brief disconnection from the ventilator to allow for adequate expiration. Ventilator strategies include: decrease RR (greatest effect), decrease tidal volume, and increase I:E time, allowing for permissive hypercapnia. Protect the alveoli by addressing PIPs via assessing the plateau pressure and acting accordingly.
Case 3: 68F with known COVID intubated for refractory hypoxia despite non-invasive therapies. Her height is 5’6” and weight is 100 kg. ABG shows 7.40/pCO2 45/pO2 48/HCO3 24 78% on TV 500 RR 18 PEEP 8 FIO2 100%. P:F ratio is 48, suggesting severe ARDS based on Berlin criteria and thus warranting lung protective strategies of low TV (6-8 cc/kg) and high PEEP (dependent on pO2; see TTS post by Dr. Shaw). Also consider proning (18.2% reduction in mortality). While inhaled nitric or Velletri should be considered, there is no proven mortality benefit.
