Colorful Day

Colorful Day Cont.

Excellent comments specially the broad DD ,proud of you all ,bUT I liked Sarmad comment very well organized , thinking of hydrocarbon toxicity which could have contributed to his altered mental status and thinking of chemical pneumonitis , ( although his chest exam and CXR were normal so less likely ) so less likely needing intubation since his presumed hyoxia is Not really due to oxygenation and ventilation issue. I was waiting for someone to mention Saturation Gap

So yes it is high methemoglobinemia( Methb) causing what looks like profound functional anemia

So what is Methb?

is an alteration in hemoglobin in which iron molecules are oxidized from the ferrous to the ferric form, ultimately leaving them unable to reversibly bind oxygen. Methemoglobin also causes a “left-shift” on the hemoglobin-dissociation curve, in which the affinity of oxygen to the hemoglobin molecule is increased and peripheral dissociation is decreased. The net result of these effects is a profound functional anemia.

CAUSES: long list ! , common things ( any nitrite product , dapsone , benzocaine)

Clinical presentation

Depends up on the level with levels below 10% usually asymptomatic or have mild symptoms

Diagnosis:

• Chocolate-colored blood

• ABG with normal or high pO2/ Low O2sat on pulse oximetry– “The Saturation Gap”

• VBG with elevated MetHb level

Antidote :

Methylene blue

• Maximum effect 30 min Elimination Bile, feces, and urine ( Hence the green color urine and stoles )

Indication :

• Methemoglobin >20%)

• Dose of 1- 2 mg/kg of 1% solution

• Slow IV push over 5 minutes

• Cyanosis resolve 15-30 minutes

• Methemoglobin drop by 50% in 30 – 60 min

Complication :

So our patient was actually cyanotic but was hard to see due to his dark skin ,he did actually have chocolate brown blood and was treated with methylene blue and and passed green color urine ( So it was colorful day after all 😊 )

Summary

• Consider the diagnosis of Methemoglobinemia in any patient with cyanosis and hypoxia that doesn’t respond to oxygen administration, remember the key finding of saturation gap

• Administer methylene blue to any patient with abnormal vital signs, metabolic acidosis, end organ dysfunction or, a serum level > 25%

References:

1. Goldfrank’s Toxicology

2. Rosen 9th edition

3. https://wikem.org/wiki/Methemoglobinemia

Q1: ABG is showing metabolic alkalosis with hypoxia and high metHb level of 42 DD:  methemoglobinemia  Hydrocarbons ingestion  Insulin overdose in the context of hypoglycaemia  Chemical pneumonitis/ aspiration pneumonia Other co ingestion to be ruled out by collater histroy especially TCA  Trauma and assault to be ruled out in the context of altered mental status  Q2:  ABCDE  keep him on 100% O2 through NRB  Methylene blue 1-2mg/kg IV over 30 min after checking G6PD status  ECG looking for arrhythmia CXR stat and to be repeated after 4 hour from onset of ingestion if known, looking for chemical pneumonitis/ARDS radiological changes  CT head to rule out brain injuries  Check blood glucose frequently  Disposition: Toxicology consultation, hyperbaric centre with ICU and ECMO facility 

So this diabetic depressed gentleman presented with AMS and hypoglycemia after attempting suicide by ingesting gasoline material mixed with charcoal lighter.

• Further history has to be taken including: history of the current toxic ingestion ( amount, time, exact material with providing us with the bottle if possible ) hx of other medications, hx of G6PD, psychiatric history.

• Clinically he has AMS, hypoglycemia, normal respiratory rate with low spo2 despite full oxygen supply. His BP is maintained with borderline tachycardia.

• ABG : methemoglobinemia 42% , PH and PCO2 are almost normal. His po2 is high. I still need an HCO3 to assess acid base balance. Diabetic with AMS would come with DKA but his ABG doesn’t show that.

• Ddx: AEIOUTIPS pneimonic has to be addressed all. Ingestion of charcoal lighter fluid ( possible compounds: alcoholic like methanol or petroleum ) in addition to gasoline ( hydrocarbons ). As he’s depressed with toxic ingestion i would also suspect other ingestions ( paracetamol and other available medications at home )

Differential diagnosis for this patient:

• Methemoglobinia

• Hydrocarbons toxicity

• Toxic alcohol

• Co-ingestion with other peds like APAP

Management:

• The managing team to wear PPEs

• Decontamination, remove all clothes and any source of the offending agent.

• Airway Airway Airway, keep intubation set standby, suction any secretion, make full assessment for impending airway compromise and alert senior physician and anasthesia.

• Continuous cardiopulmonary monitoring with capnography with stat 12 lead ECG

• Repeated ABCDE assessmemt with monitoring blood glucose.

• Methylene blue. As having evidence of MetHb > 30% with symptoms then indicated, consult toxicologist while giving. Make sure patient is G6PD negative.

• Hydration, full sets of labs. Including lytes, osmolality, osmolar gab and lactate

• APAP level after 4 hours of ingestion

• VBG every 1-2 hours to assess for acidosis and MetHb level in response to methylene blue.

• Avoid activated charcoal as its acoustic ingestion and avoid NGT

• CT brain if indicated by any finding in neurological exam or clinical judgment

• CXR to assess for pneumonitis

• ICU admission

• Toxicology Review

• Psychiatrist assessment

So this patient presenting with altered sensorium level with gcs of 13. Have low saturation dispite he's on 100% O2. From the history his family gives a history of hydrocarbon ingestion but since he's depression disorder we need to keep in mind other co-ingestion can cause altered sensorium plus other non toxic causes ( comes with nemonic : AIUEO TIPS) So first Will approach patient with ABCDE with decontamination if skin exposed. ABG shows elevated MetHB level above 40% which can explain his symptoms ( I will comment if there is the typical chocolate blood color during blood collection ) , so will give him methylene blue 1mg/kg which can be repeated after 30 minutes if no improvement ( and to watch any s.e. Mainly GI symptoms) Disposition plan patient need icu observation and an psychatric consultation before admission.

Q1: This is a patient showing clinical and ABG findings of metHemoglobinemia most probably due to intoxication ?ingestion of malaria pills, to my knowledge that hydrocarbons don't cause methemoglobinemia. HOWEVER, he is also taking OHA so possibility of metformin toxicity is also on board (low BP low glucose), as he is a case of suicidal attempt we also need to r/o other causes like BB or CCB intake. Need to look for and treat for all! Further history from relatives (available pills at home) might help. Q2: He will need methylene blue (r/o G6PD deficiency prior to giving). Keep on NRM 100% oxygen while preparing medication and perform ABCDE SAMPLE and 2nd survey that will help r/o other causes, 2 large bore cannulas, repeat vitals every 5mins as we expect cardiogenic shock

With that we need the following:

-Avoid NGT as patient might get chemical pneumonitis from aspiration

-Toxicology consultation +/-hyperbaric center, anasthesia/senior ED practitioner: patient might require intubation with very low saturation we anticipate need for successful intubation with minimal trials

-ECG and trops as indicated to r/o cardiac causes, he is tachycardic and with low saturation, ?TFT if indicated

-Bed side US RUSH protocol for treating reversible causes, hydrate with boluses and look for response clinically+IVC+lactate clearance+urine output and start vasopressor if indicated

-CXR: ?pneumonia ?CHF

-CBC: specifically looking for Hb level

-CT brain: r/o intracranial causes

-IV abx to cover chest infection and even later evolving chemical aspiration pneumonia

Disposition: ICU at a hospital with ECMO and HD services+psychiatry consultation