A randomized, controlled clinical trial of intravenous lipid emulsion as an adjunctive treatment for permethrin toxicosis in cats

[Mycotoxin intoxication in 54 dogs after ingestion of walnuts]

OBJECTIVE

The aim of this retrospective study was to decribe the intoxication with tremorgenic mycotoxins subsequent to the ingestion of walnuts in a large population of dogs and the evaluation of the development of the clinical signs under the initiated treatment.

MATERIAL AND METHODS

The study included 54 dogs exhibiting signs of tremor, hyperesthesia, hyperthermia and ataxia, in particular a few hours following observed ingestion of walnuts or its justified suspicion.

RESULTS

The patients were presented to the clinic mostly during winter and spring. Fifty-three of 54 dogs were hospitalized for symptomatic, decontaminating and eliminating therapy (98%). Symptomatic treatment comprised of anticonvulsant therapy in 14 dogs (26%) and an antiemetic therapy in for half of the patients (n=27; 50%). A forced emesis for decontamination was undertaken in only 6 patients due to the severity of their neurological symptoms (11%). For further decontamination, an oral administration of activated charcoal after improvement of clinical signs (n=39; 72%). The majority of dogs (n=45; 83%) additionally received an intravenous lipid therapy for toxin elimination and isotonic crystalloid solution to compensate fluid losses. There were no side effects observed following the administration of intravenous lipid therapy. The majority of dogs were hospitalized for a duration of 2 days (n=44; 81%). In most dogs, examination was unremarkable on the day of their release (n=39; 72%). Potential long-term sequelae of the intoxication were not recorded in any patient.

CONCLUSION

Due to the lipophilic nature of mycotoxins, the use of intravenous lipid therapy may considered for toxin elimination purposes. The prognosis of mycotoxin intoxication following walnut ingestion is good with decontamination and elimination measures.

CLINICAL RELEVANCE

In the case of unspecific neurological signs such as tremor, ataxia and hyperesthesia as well as a corresponding preliminary report, an intoxication with mycotoxin-containing walnuts should be considered.

Clinical effects and adverse effects of intravenous lipid emulsion treatment in dogs and cats with suspected poisoning

This retrospective study aimed to evaluate the effects on the clinical signs of poisoning and adverse effects of intravenous lipid emulsion treatment in 82 animals (dogs and cats) with suspected poisonings over 18 months. Physical examination parameters and state of consciousness were documented every hour after the intravenous administration of a bolus of 2 ml/kg and 0.25 ml/kg/min over 60 minutes of a 20% intravenous lipid emulsion. The modified Glasgow coma scale and laboratory findings (blood gas analysis, triglyceride, lactate) were evaluated initially and three hours after discontinuing intravenous lipid emulsion administration. A statistical evaluation of the occurrence of adverse effects and the development of laboratory values was performed. A decrease in respiratory rate in the second control (8-12 hours) after ILE was observed. Three hours after completing of the intravenous lipid emulsion, triglyceride concentration increased about 10 times (p <0.001). Venous carbon dioxide partial pressure, bicarbonate, base excess, as well as the electrolytes sodium, potassium and ionized calcium decreased significantly (p <0.001). Patients who experienced a worsening of the modified Glasgow coma scale had a higher increase in triglyceride concentrations (p = 0.041) and plasma lactate (p = 0.034) and a larger decrease in bicarbonate concentrations (p = 0.053) compared to others. About 54% (n = 44) of the patients showed adverse effects which could be attributed to the administration of intravenous lipid emulsion and may be associated with a higher triglyceride increase. All of them were completely reversible within 33 hours. Adverse effects associated with intravenous lipid emulsion therapy were observed in half of the patients and were associated with a higher increase in triglycerides.

Alpha-chloralose poisoning in 25 cats: clinical picture and evaluation of treatment with intravenous lipid emulsion

OBJECTIVES

The aims of this study were to describe the clinical picture and progression in cats with alpha-chloralose (AC) intoxication and to determine if treatment with intravenous (IV) lipid emulsion (ILE) influenced either the serum concentration of AC or the clinical signs.

METHODS

Cats with suspected AC poisoning admitted to a university small animal hospital were included. The cats were randomised into two groups: one receiving 20% ILE at a dose of 300 mg/kg as a 2 min bolus, followed by a 1500 mg/kg continuous rate infusion over 30 mins (IL+ group) and the other receiving IV fluid therapy with Ringer's acetate (IL- group). Serum samples were drawn at 0, 2, 12 and 24 h after admission. Samples were tested for AC with a novel validated, quantitative, ultra-high-performance liquid chromatography-tandem mass spectrometry method. Vital and predefined clinical signs were noted at the times of sampling and patients were scored using a previously described intoxication severity score. Telephone interviews were conducted after discharge to assess outcome.

RESULTS

A total of 25 cats were enrolled: 13 cats in the IL+ group and 12 in the IL- group. The most common clinical signs at presentation were tremor (n = 22, 88.0%), cranial nerve deficits (n = 20, 80.0%) and bradycardia (n = 19, 76.0%). No significant difference in AC concentration or change in intoxication score over time was found between the IL+ and IL- groups at any time point (P >0.05). All cats recovered within 72 h.

CONCLUSIONS AND RELEVANCE

ILE did not have any effect on the AC serum concentration or clinical signs in AC-poisoned cats. All cats survived until follow-up. In cats with an acute onset of the described neurological signs, AC intoxication is an important differential diagnosis with an excellent prognosis.

Intravenous lipid emulsion for the treatment of poisonings in 313 dogs and 100 cats (2016-2020)

Introduction

The aim of this retrospective study was to analyze the effect and potential adverse effects of intravenous lipid emulsion (ILE) in poisoned dogs and cats over a 5 years period.

Methods

Medical records of 313 dogs and 100 cats receiving ILE between 2016-2020 were analyzed for suspected toxicant, clinical signs, ILE dosages and frequency, the effect and adverse effects of ILE, and patient outcome.

Results

Dogs and cats were poisoned with mostly unidentified toxicants (48%), rodenticides (8%), recreational drugs and nuts (7% each) and other toxicants. Clinical signs included neurologic deficits (63%), cardiovascular signs (29%), thermoregulation (21%) or gastrointestinal abnormalities (17%). Treatment with ILE was initiated within a median of 6.0 h (1.0-91.0 h) after poisoning. Dogs and cats received a total amount of median 8.0 mL/kg (1.5-66.6 mL/kg) and 15.8 mL/kg (1.8-69.4 mL/kg) ILE, respectively. A positive effect was observed in 74% of the patients, whereas clinical signs worsened in 4% of the patients after ILE administration. No subjective effect was detected in 22% of the patients. Suspected or possible adverse effects of ILE occurred in 6% of the patients, including neurological signs (temporarily reduced consciousness and ataxia), bradycardia, hyperthermia, vomiting, diarrhea, respiratory distress, worsening of the general behavior, facial swelling, and thrombophlebitis. The overall survival rate was 96%. One dog who potentially experienced adverse events was euthanized.

Conclusion

ILE treatment was successful in most patients but can be associated with adverse effects. Administration of ILE should be carefully selected on an individual basis after weighing the possible benefits against potential adverse effects.

A retrospective evaluation of confirmed and suspected poisonings in 166 cats between 2016 and 2020

Background and Aim

Poisonings commonly bring cats and dogs to veterinary emergency facilities. This retrospective study aimed to analyze clinical signs, confirmed or suspected toxicants, treatments, and outcomes of feline poisoning cases presented over 5 years to the emergency service of a small animal referral center.

Materials and Methods

Medical records of 166 cats were evaluated for a history of confirmed or presumed poisoning, suspected toxicant, clinical signs, treatment, and outcome. Poisoning probability was determined using patient history, clinical findings, observation, toxicologic examination, and, in some cases, gastric contents.

Results

Most cats were hospitalized (94.0%) due to poisoning with mostly unknown toxicants (48.2%), rodenticides (21.1%), and various toxic plants (12.0%), followed by antiparasitics (6.0%), chemicals (6.0%), drugs (4.2%), tetrahydrocannabinol (1.2%), or inhaled smoke (1.2%). Patients presented predominantly with neurologic deficits (68.7%), reduced general condition (60.2%), and hypothermia (43.4%). The survival rate was 88.6%. Most cats (93.2%) showed no apparent complications at the time of discharge from the hospital. Toxicant-related complications (48.2%) included thermodysregulation (22.9%), central nervous system signs (18.7%), respiratory issues (7.2%), nephrotoxicity (6.0%), gastrointestinal complications (4.8%), evidence of hepatic failure (4.8%), and hemorrhage (1.8%).

Conclusion

In this study, the causative toxicant remained unidentified in many cases. Known poisonings were mostly caused by rodenticides. Neurological signs were the most common clinical presentation. Survival rates were high and comparable with those reported by others.

Treatment of Permethrin Toxicosis in Cats by Intravenous Lipid Emulsion

Background: In this study, the clinical response to treatment with intravenous lipid emulsion (ILE) for nine cats intoxicated with permethrin has been described. Methods: The enrolled cats showed acute onset of seizures, tremors and hypersalivation that were partially controlled with the administration of benzodiazepines and intravenous fluid therapy. Due to worsening clinical signs, intravenous lipid emulsion (intralipid 20%; 1.5 mL/kg in bolus, followed by 15 mL/kg for 1 h in infusion) was administered. Results: After ILE treatment, all cats recovered rapidly and were discharged within 24–54 h. Intravenous lipid emulsion appears to be a relatively safe and inexpensive alternative, with a short hospitalization time. Conclusions: Intravenous lipid emulsion could be an interesting therapeutic option in emergency and critical care protocols for permethrin toxicosis.

Conventional treatment of a metaldehyde-intoxicated cat with additional use of low-dose intravenous lipid emulsion

Case summary

An adult male intact domestic shorthair cat was presented for acute onset of generalised tremors, stupor, horizontal nystagmus, anisocoria and bilateral absence of pupillary light and palpebral reflexes. Response to intravenous (IV) administration of benzodiazepines was minimal; thus, the induction of general anaesthesia with propofol, midazolam and dexmedetomidine was necessary to control clinical signs. Following a clinical suspicion of neurotoxicosis, a low-dose constant rate infusion (CRI) of IV lipid emulsion (ILE) was started. Phenobarbital and a low-dose CRI of ketamine were also used for neuroprotective purposes. Metaldehyde intoxication was confirmed by qualitative faecal toxicological analysis after discharge. Anaesthetic drugs were progressively tapered and stopped after 28 h and extubation was possible after 44 h. The cat was discharged 8 days after admission with a complete recovery of the clinical signs.

Relevance and novel information

To the authors’ knowledge, this is the first report to describe a case of metaldehyde toxicosis in a cat treated with intensive supportive care and an additional low-dose CRI of ILE.

Successful Management of Severe Bromethalin Toxicosis in a Dog

ABSTRACT The use of bromethalin rodenticides has risen since 2011, and in some states, it is the most common rodenticide ingestion reported to poison control. Although intravenous lipid emulsion (ILE) has been previously reported to lower serum desmethylbromethalin levels in an asymptomatic dog, and repeated mannitol has been investigated in a laboratory setting, there are no published reports of successful treatment of symptomatic bromethalin toxicosis in dogs. A 9 yr old castrated male Norwich terrier was evaluated for obtunded mentation, seizures, cranial nerve deficits, and tetraparesis secondary to bromethalin toxicosis. The patient was treated with ILE, mannitol, and ginkgo biloba and returned to normal neurological function. Bromethalin exposure was confirmed by serum desmethylbromethalin levels. Previous literature indicates that the prognosis for patients who suffer from symptomatic bromethalin toxicosis is poor to grave, and the return to normal neurological function after severe toxicosis has not been reported. ILE, mannitol, and ginkgo biloba are readily available and relatively inexpensive, and in combination may be of benefit in symptomatic bromethalin intoxication.

Oxidative red blood cell damage associated with propofol and intravenous lipid emulsion therapy in a dog treated for 5-fluorouracil toxicosis

OBJECTIVE

To describe the first documented case of oxidant-induced anemia in a dog associated with propofol and IV lipid emulsion (IVLE) treatment for 5-fluorouracil (5-FU) toxicosis.

CASE SUMMARY

A 2-year-old male intact mixed breed dog was presented for evaluation after ingestion of 5% 5-FU cream. Refractory reactive seizures rapidly developed, and treatment with benzodiazepines, propofol, levetiracetam, and IVLE was initiated. The dog was euthanized due to development of marked oxidant-induced anemia.

NEW INFORMATION PROVIDED

This report documents the first instance of oxidant-induced anemia in the dog, associated with propofol and IVLE infusion therapy prescribed for treatment of 5-FU toxicosis.

Use of intravenous lipid therapy in a cat with carprofen overdose

Intravenous lipid emulsion (ILE) was administered to a cat with no adverse effects. This case report postulates that ILE can be used for the treatment of carprofen toxicity in cats and supports the lipid sink theory as the main mechanism of action.

Pyrethroid Poisoning

Introduction

Pyrethroid compounds are widely used as insecticides. These compounds not only have a versatile application, but also have favourable toxicological profiles with high selectivity and toxicity to insects and low toxicity to humans. Despite this, there have been several reports of toxicity to humans in both occupational exposure and deliberate ingestional poisoning.

Classical presentation and treatment

Two classical syndromic presentations are described. Type I syndrome is characterised predominantly by tremors and is seen with exposure to type I pyrethroids. Type II pyrethroids, which are structurally modified type I pyrethroids with the addition of a cyano group, can result in type II syndrome characterized by choreo-athetosis and salivation. Mega-dose poisoning and mixed poisoning, particularly with organophosphorus compounds, is associated with significant toxicity and death. Treatment is supportive and symptomatic. A favourable outcome can be expected in most patients.

How to cite this article

Ramchandra AM, Chacko B, Victor PJ. Pyrethroid Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S267–S271.

[Emergency management of intoxications in the dog and cat]

Intoxications may lead to life-threatening emergencies. While stabilising the patient, therapy should focus on a rapid and effective elimination of the toxin. General measures for decontamination (gastrointestinal, dermal, ocular) aim to effectively decrease the absorption of the poisonous substance. Further classification of the substance and its properties can assist with the choice of specific treatment options, including dialysis and specific antidotal therapy. In recent years, treatment with lipid emulsions for enhanced elimination of lipophilic substances has become an important therapeutic option. In affected patients, it can rapidly improve clinical signs while side effects and complications are rarely encountered with this form of therapy.