Dr. Terencia. A, Dr. Sajith Kesavan/Dr.Greeshma Issac, Dr. C Jayalumar
AIMS, KOCHI
one month old ba was shown to periphery hospital with alleged history of intentional ingestion of Paraquat( herbicide), following which the ba developed 2 episodes of vomiting with bluish discolouration of vomitus and urine with drooling of saliva since past 2 days. Poisoning was suspected and toxicology samples were collected and sent to AIMS Toxicology centre . Mother suffering from postpartum psychosis has confessed that she has given the poison with vitamin’s drops. H/. Stomach was was given immediately
No h/o any hematemesis.
Birth history: 1st child of NCM with uneventful perinatal history
H/o post partum depression in mother +
At admission, Child was irritable and afebrile
Vitals: Temp: 106 F, PR- 188/min,
RR- 46/min, BP-106/56 mmHg,
SpO2 98% on room air, CRT <3s
No pallor, icterus, cyanosis, clubbing, lymphadenopathy, edema.
Erythematous swollen tongue
Drooling +
Systemic Examination
Resp: conducted sounds +
CVS: S1S2 +
P/A: soft, non tender, no organomegaly; BS+
CNS: No FND Figure 1 showing paraquat blue colored tongue
Initial labs CRP(TC-4.5k/Ul, N-33%, L-51%, Hb-7.6g/dl, Plt-360k/uL). LFT, RFT AND S.Electrolytes done were normal.
Toxicology samples (Urine and gastric aspirate) sent from outside hospital was positive for paraquat. At the time of admission, ba had noisy breathing, blue coated tongue, vitals were stable and was on room air.
Haemoperfusion was planned. Ba was mechanically ventilated, Central line/ Vascular Catheter was inserted, and during the procedure child was supported with noradrenaline after which one cycle of hemoperfusion with heparinization was done.
Figure 2-Showing repeat Bedside paraquat semi quantitative test done was + in urine samples
Child was extubated on day 3 of admission Child had non oliguric AKI which did not need renal replacement.
Other supportive medications were continued(NAC infusion/ Pan / Oral sucralfate /IV fluids).
Glycopyrrolate was added in view of secretions
Repeat toxicology sent was negative for paraquat in blood and urine. Oxygen requirement was observed post extubation (on day 3 of admission) which increased progressively with x-ray showed increasing bilateral haziness -requiring upto 8 litres flow with Fio2 50 % on day 6 of admission with sats of 88-90%.
Ba was started on IV methylprednisolone in view of the increasing oxygen requirement.
CT was done on day 7 of admission which showed extensive areas of ground glass appearance indicating lung injury.
After discussion with rheumatology, one dose of cyclophosphamide (15mg/kg/dose) was administered with IV dexamethasone (10mg/sq.m) on Day 7 of admission. This was followed a decreasing trend of o2 requirement and ba was off o2 support day 14 of admission.
Blood culture sent during hospital stay revealed MRSA growth, IV antibitoics were given appropriately.
Barium Swallow study done was normal. Gastroenterology review was sought and OGD scopy was done, which showed no strictures/ erosion. Oral feeds were started and NG tube was removed.
Ba is tolerating oral feeds and is being discharged with the following advice.Steroids were gradually tapered and stopped.
Paraquat is a rapidly-acting, nonselective herbicide that is highly toxic when ingested and a leading cause of fatal poisoning.Topical and inhalational exposure is far less toxic.
Swallowing more than 30 mL (a mouthful or two) of 20 to 24 percent paraquat concentrate is usually lethal, and as little as 10 mL can cause significant illness. Therefore, it is important to know the concentration and dose of paraquat.
●Clinical features of poisoning – Patients who have ingested paraquat often complain of mouth pain, pain with swallowing, nausea, vomiting, and abdominal pain. A “burning skin” sensation is common. Respiratory complaints indicate systemic poisoning and are associated with fatal outcomes.
Important examination findings associated with paraquat poisoning include pulmonary abnormalities (dyspnea, tachypnea, hypoxia, ϲraϲkles), tachycardia, hypotension, oral lesions, and abdominal tenderness.
Symptoms and signs of paraquat poisoning usually manifest within 12 hours so patients should generally be monitored for at least this duration.
Laboratory testing – In patients with significant poisoning, blood tests should be obtained on admission and then repeated every 6 to 12 hours for the first 48 hours. Recommended tests are complete blood count (CBC), serum chemistries, blood gas, and arterial lactate. Often, tests are used to help determine the prognosis and serial tests are unnecessary if the prognosis is poor.
●Diagnosis – The diagnosis of paraquat poisoning is suspected from a history of ingestion, or other exposure, along with strong supporting evidence from the physical examination, notably the presence of oropharyngeal burns in the case of oral exposure, and the subsequent development of acute kidney injury, metabolic acidosis, or acute respiratory distress syndrome. The diagnosis is confirmed with urine or blood tests.
•Adding dithionite solution to a urine sample is a qualitative test used to confirm or exclude exposure to paraquat. A negative urinary dithionite test on a fresh urine sample six hours after ingestion suggests that exposure was minimal and the patient can be medically cleared if asymptomatic.
•A serum paraquat concentration, although not routinely available, predicts the likelihood of death following acute poisoning when plotted relative to the time of ingestion on predictive nomograms.
●Overview of management – The management of paraquat exposure is determined on an individual basis depending upon the amount ingested and the time elapsed since the exposure. Overall, none of the current treatments have proven effective for patients with signs of severe poisoning and prognosis is uniformly poor in all centers, including those who treat aggressively with multimodal therapies.
•Resuscitation of the patient with acute paraquat poisoning follows standard guidelines except that oxygen therapy should not be administered unless there is confirmed hypoxia, as it may exacerbate the oxygen-mediated cellular damage.
•Fluid losses are usually treated with 2 or 3 L of isotonic crystalloid; larger volumes may be needed if there is greater than a 24-hour delay in presentation.
•Continuous pulse oximetry is required to monitor for deteriorating gas exchange. Signs of severe systemic illness (eg, severe hypoxia, hypotension, or acidosis) indicate a poor prognosis.
●Gastrointestinal decontamination – In patients who present within approximately two hours of ingestion, we suggest that activated ϲharϲοаl (1 g/kg in water; maximum dose 50 g) or Fuller’s earth (2 g/kg in water; maximum dose 150 g in water) be given as soon as possible per oral or via a nasogastric tube.
●Extracorporeal therapy – In all patients with confirmed paraquat exposure who can have extracorporeal therapy initiated within four hours of ingestion, we suggest treatment with hеmοреrfսѕiоո or hеmοԁialуѕis. Ηеmοреrfuѕion or hеmοԁiаlуsis are continued for four hours.
●Antiinflammatory and antioxidant therapies – For patients manifesting systemic toxicity but without signs of inevitable death, we suggest treatment with high-dose glucocorticoids and acetylcysteine. We typically use dexamethasone 8 mg intravenously (IV) every eight hours, for several weeks, and acetylcysteine 300 mg/kg per day while hospitalized. These antidotes are of low toxicity and might provide some small benefit.
TAKE OVER MESSAGE-
The management of paraquat exposure is determined on an individual basis depending upon the amount ingested and the time elapsed since the exposure. None of the current treatments have proven effective for patients with severe poisoning and prognosis is uniformly poor in all centers, including those who treat aggressively with multimodal therapies. Symptoms and signs of paraquat poisoning usually manifest within 12 hours so patients should be monitored for at least this duration. However, a negative urinary dithionite test beyond six hours post-ingestion suggests that exposure was minimal and the patient can be medically cleared if asymptomatic. Ηеmοреrfսѕiоո or hеmοdiаlуsiѕ followed continuous hemodiafiltration or repeated hеmοреrfսѕiοո may be beneficial if commenced within four hours of poisoning.