Interesting Case Rounds

Rebecca Burton-MacLeod

R5 (yikes!), Emerg Med

July 5th, 2007

Case

21M presents to ED c/o CPX ~4 hrs

Retrosternal, radiated bilaterally

Not pleuritic

+ SOB +nauseas; not dizzy, no palpitations

Also c/o generalized abdo pain, and pain to bilateral thighs (present x2days)

History cont’d

No previous similar episodes, but sometimes his legs “have pain” Pt moved from India about 2mos prior, ++ language barrier !

PMHx: “healthy”Meds: noneAllergies: none

Further hx

Questions ?

Physical examHR 115, BP 128/72, RR 26, Temp 37.9, sats 92% r/aPt ++ uncomfortable, tearfulCNS—A+OCVS—N heart sounds, PPPResp—lungs clearAbdo—generalized mild tenderness, no guarding, no rebound, + BSMSK—c/o ++ tenderness to palpation bilateral thighs; no erythema or swelling noted

Investigations

??

Investigations

CXR

EKG

CBC, lytes, Cr

EKG

Bloodwork

Hgb 77

Plt 185

WBC 31

Lytes, Cr N

“Have you ever been told you have anemia before?”…

Sickle cell disease

Autosomal recessive disease

Caused by substitution of valine for glutamine in Hgb beta-chain (Hgb S)

Sickle cell distribution

Sickle cell crisis

Vaso-occlusive crisis

Aplastic crisis

Splenic sequestration

Acute chest syndrome

Infections

Case cont’d

Pt received:IV N/S 1L bolus; 2x maintenance fluids

IV morphine 5mg boluses to total of 20mg

Oxygen by n.p.

Case cont’d

Called back to see pt as noted to be ++SOB

Sats now 85% on r/a

Clinically—wheezes and crackles heard bilaterally on auscultation of lungs

Temp now 38.7C

ABG—on 8L O2: pH 7.24 /CO2 51 /O2 50; lactate 12

Any thoughts ?

Acute chest s/oDefined as:

New infiltrate on CXRAssociated with new symptoms (fever, cough, sputum production, dyspnea, hypoxia)

Occurs in 50% of SCD pts; recurrent in 80%Preceded by vaso-occlusive crisis in half of patientsLeading cause of death for pts with SCD

http://ajrccm.atsjournals.org/content/vol159/issue5/images/large/RCCM9810094.f3.jpeg

Risk factors for ACSYoungHomozygous sickle-cell genotype FeverWinter monthsSurgeryPrevious ACS eventsAVN of bonesHigh Hgb levelsLow fetal Hgb levelsHigh steady-state leukocyte counts

Pathophysiology

Infection

Fat embolism

Thromboembolism

Vaso-occlusive sickling erythrocytes

Hypoventilation due to rib/sternal infarction and pain

Hypoventilation due to narcotic administration

Pulmonary edema due to fluid overload

Sign / symptoms

~25% of adults have other symptoms of pain (usually lower extremities)

Mgmt

Identify and treat precipitating factors

Maintain/improve oxygenation

Prevent further alveolar collapse

Maintain adequate fluid volume

Control pain

Treat underlying infection

Oxygenation

Administer O2 to keep PaO2 ~70-100

Pts may require simple, or exchange transfusions (allow removal of Hgb S) if severe anemia

Incentive spirometry, CPAP, or intubation/ mechanical ventilation with PEEP

Indications for exchange tx

Evidence of rapid clinical deterioration

SaO2 <80% despite aggressive ventilatory support

Serial decline in SaO2

Worsening/unstable vital signs

Persistent RR >30/min

Maintain fluid volume Replenish dehydration with N/S

For further fluid volume, use D5W/0.25N/SHypotonic fluids preferred as allows water to enter RBC

Causes osmotic swelling and reduced tendency for sickling

Treat underlying infection

2nd-3rd gen cephalosporin +/- macrolideBacteremia in ~3.5% of cases of ACS

Strep pneumoniaeH. fluStaph aureusSalmonellaEnterobacterClostridia

Other therapies

DBRCT of IV dex in peds (n=43) showed SS shorter hosp stays, dec blood transfusions, dec clinical deterioration

Multiple case reports and animal studies of nitric oxide improving pt symptoms (lack of NO bioavailability in SCD)

Poloxamer-188 (non-ionic surfactant) may shorten duration of ACS and length of hospitalization (n=43)

Questions ?

References RosensBallas SK, et al. Safety of purified poloxamer 188 in SCD. Hemoglobin. 2004.Bernini JC, et al. Beneficial effects of IV dexamethasone in children with mild to mod severe ACS complicating SCD. Blood. 1998. Gladwin MT, et al. The ACS in SCD. Am J Resp Crit Care Med. 1999.Kararmaz, A et al. ACS in a patient with SC anemia successfully treated with erythrocytopheresis. Int J Emerg Inten Care Med. 2006.Machado RF. Nitric oxide based therapies in SCD: the evidence continues to mount. Crit Care Med. 2007.Vichinsky EP, et al. ACS in SCD: clinical presentation and course. Blood. 1997. Yale SH, et al. ACS in SCD. Postgrad Med. 2000.