The role of on-site drug analysis within supervised injecting facilities: A case presentation of an adverse event highlighting need

INTRODUCTION

The Sydney Medically Supervised Injecting Centre provides a safe, non-judgemental space where people can inject pre-obtained substances under the supervision of trained staff. This article describes an unusual incident occurring at the Medically Supervised Injecting Centre in January 2023.

CASE PRESENTATION

Two regular male clients attending the Medically Supervised Injecting Centre injected a substance they believed to be cocaine. Both clients experienced adverse reactions; one was transported to hospital, while the other became extremely distressed and agitated. Paraphernalia sent for testing returned a result of tiletamine (a dissociative used in veterinary medicine) and no cocaine, 30 h after the incident.

DISCUSSION AND CONCLUSIONS

Where substances are novel or unknown, adverse events are often unexpected and may be more difficult to prepare for. Substance-induced acute agitation can be alarming and hazardous for people consuming drugs and those around them and may pose challenges for staff. There is a substantial evidence base for the benefits of on-site drug analysis and drug checking in reducing harms related to drug use, and in enhancing drug market monitoring. This incident was successfully managed by Medically Supervised Injecting Centre and hospital staff, with no major consequence, however clinical management could have been improved using point of care drug testing.

Immobilization of captive plains zebras (Equus quagga) with a combination of etorphine hydrochloride, acepromazine, and xylazine hydrochloride

The plains zebra (Equus quagga) is a zebra species commonly kept in zoos around the world. However, they are not tame like their domestic relatives and are difficult to immobilize. We immobilized 30 captive plains zebra with a combination of etorphine hydrochloride (2-4 mg), acepromazine (8 mg), and xylazine hydrochloride (30 or 50 mg) to perform physical examination and blood sample collection for disease diagnostics. Physiological parameters including heart rate, respiratory rate, body temperature, and hemoglobin oxygen saturation were recorded. All zebras exhibited satisfactory anesthesia and fully recovered without re-narcotization. The results suggest that etorphine hydrochloride-acepromazine-xylazine hydrochloride combination for plains zebra immobilization is a safe and sufficient regimen for short procedures such as wellness examinations and sample collection.

Evaluation of intramuscular anesthetic protocols in healthy domestic horses

OBJECTIVE

To assess anesthetic induction, recovery quality and cardiopulmonary variables after intramuscular (IM) injection of three drug combinations for immobilization of horses.

STUDY DESIGN

Randomized, blinded, three-way crossover prospective design.

ANIMALS

A total of eight healthy adult horses weighing 470-575 kg.

METHODS

Horses were administered three treatments IM separated by ≥1 week. Combinations were tiletamine-zolazepam (1.2 mg kg^-1), ketamine (1 mg kg^-1) and detomidine (0.04 mg kg^-1) (treatment TKD); ketamine (3 mg kg^-1) and detomidine (0.04 mg kg^-1) (treatment KD); and tiletamine-zolazepam (2.4 mg kg^-1) and detomidine (0.04 mg kg^-1) (treatment TD). Parametric data were analyzed using mixed model linear regression. Nonparametric data were compared using Skillings-Mack test. A p value <0.05 was considered statistically significant.

RESULTS

All horses in treatment TD became recumbent. In treatments KD and TKD, one horse remained standing. PaO₂ 15 minutes after recumbency was significantly lower in treatments TD (p < 0.0005) and TKD (p = 0.001) than in treatment KD. Times to first movement (25 ± 15 minutes) and sternal recumbency (55 ± 11 minutes) in treatment KD were faster than in treatments TD (57 ± 17 and 76 ± 19 minutes; p < 0.0005, p = 0.001) and TKD (45 ± 18 and 73 ± 31 minutes; p = 0.005, p = 0.021). There were no differences in induction quality, muscle relaxation score, number of attempts to stand or recovery quality.

CONCLUSIONS AND CLINICAL RELEVANCE

In domestic horses, IM injections of tiletamine-zolazepam-detomidine resulted in more reliable recumbency with a longer duration when compared with ketamine-detomidine and tiletamine-zolazepam-ketamine-detomidine. Recoveries were comparable among protocols.

Evaluation of Medetomidine-Ketamine for Immobilization of Feral Horses in Romania

Feral horses are immobilized for a variety of reasons including population control via contraceptives. Although opioid combinations have been successfully used for immobilization of feral horses, there is a need for combinations using drugs that are more readily available and present less of a human health hazard. We evaluated the chemical immobilization with physiological measurements and blood gas analyses of 91 free-ranging feral horses (Equus ferus caballus) remotely immobilized with a combination of 30 mg medetomidine and 775 mg ketamine in a single disposable 6 ml dart. During immobilization, heart rate, respiratory rate, rectal temperature, capillary refill time and peripheral oxygen hemoglobin saturation (SpO₂) were evaluated. In eight horses, arterial blood samples were analyzed to evaluate the blood gases, acid-base status and hematologic variables. Targeted horses presented a wide range of age, size and body condition. Eighty-one horses had an uneventful mean induction of 7.2 min. Eighty-nine horses were immobilized in lateral recumbency with good muscle relaxation and a median recumbency time of 67 min. Ten horses required supplemental ketamine intravenously (x̄ = 434 mg) due to incomplete immobilization. In 58 horses the effects of medetomidine were antagonized with atipamezole intravenously. Increased respiratory rate (>20 breaths/min), increased heart rate (>45 beats/min) and decreased SpO₂ < 90% were noted in more than half of the individuals, while increased rectal temperature (>39.0°C) was recorded in six animals. Blood parameters showed hypoxemia (<90 mmHg, n = 8), hypercapnia (>45 mmHg, n = 5), high glucose levels (>134 mmol/L, n = 3), increased blood lactate (>1.5 mmol/L), total carbon dioxide, bicarbonate and base excess which further increased in the second sample, whereas SpO₂ and calcium values decreased. Recoveries were smooth, with one (n = 86) or more (n = 5) attempts of standing. Eighty-nine recoveries were uneventful, besides one male that showed signs of monoparesis of the left front leg and one mare with signs consistent with exertional myopathy. In conclusion, medetomidine-ketamine provided a reliable immobilization in feral horses over a wide range of body mass and age. However, based on the observed hypoxemia during immobilization, oxygen supplementation is strongly recommended for this protocol.

Retrospective and prospective assessment of butorphanol, azaperone and medetomidine (BAM™) for immobilisation of feral horses (Equus ferus caballus)

BACKGROUND

Butorphanol-azaperone-medetomidine (BAM™) has not been evaluated in horses.

OBJECTIVES

The objective of this study was to evaluate BAM™ for chemical restraint of feral horses.

STUDY DESIGN

Retrospective and prospective descriptive studies.

METHODS

Data were collected retrospectively from medical records of 28 feral horses immobilised with BAM™ over a 6-year period. Prospectively, 0.0125 mL/kg bwt of BAM™ (butorphanol 27.3 mg/mL, azaperone 9.1 mg/mL and medetomidine 10.9 mg/mL) intramuscularly (im) was administered to eight stallions via dart, and once recumbent, 1.0 mg/kg bwt ketamine was given intravenously (iv). Induction and recovery time and quality via a standardised rubric (1 = very poor; 5 = excellent) and visual analogue scale (VAS), need for additional darts, weight tape measurement and serial physiological parameters were recorded. Serial arterial blood gas analysis was performed during recumbency. Following castration, horses were given 0.1 mg/kg bwt atipamezole (25% iv and 75% im) and allowed to recover unaided.

RESULTS

Retrospectively, 28 horses were successfully immobilised with BAM™ without a major complication. Prospectively, eight horses were given a median (range) actual BAM^TM dose of 0.0143 (0.0127-0.0510) mL/kg bwt. Three of eight horses needed 1, 2 or 5 additional darts. Median (range) time to recumbency was 11 (2-44) minutes. Median (range) induction (n = 4) and recovery (n = 6) scores via rubric and VAS were 5 (4-5) and 5 (5-5) and 92 (86-93) and 98 (92-99) cm, respectively. Four of seven horses were hypoxaemic at ≥1 time point with otherwise acceptable physiological parameters. Following atipamezole, median (range) time to sternal recumbency and standing was 12 (2-18) and 17 (11-52) minutes, respectively (n = 6).

MAIN LIMITATIONS

The sample size was small. Data could not be collected before darting or after recovery. Some data were missing from retrospective analysis.

CONCLUSIONS

Intramuscular BAM™ with iv ketamine provided chemical restraint suitable for field castration of feral horses with no mortality. Hypoxaemia occurred in the majority of horses.

Variation of Hematochemical Profile and Vitamin E Status in Feral Giara Horses From Free Grazing in the Wild to Hay Feeding During Captivity

Wildlife protection and management are important priorities for landscape identity and biodiversity preservation. Feeding practices of fauna confined in facilities during temporary captivity are fundamental to support animal health and natural behavior. Appropriate provision of feedstuffs appears to be necessary to support the best practices in respect of animal species-specific natural diet. This investigation explored the variation of the metabolic profile by means of selected metabolite and respective circulating levels in a group feral Giara horses undergoing the change of the diet, moving from natural free grazing in the wild to temporary captivity. Six Giara horses (4 mares and 2 stallions; estimated age: 2.5-3 years; body weight: 163-170 kg) were captured to monitor the serological reaction to equine infectious anemia (EIA; screening at Coggins test). Animals were sheltered in a wildlife rescue center for a duration of 4 weeks, and all received the same hay-based diet (ad libitum). On 0 and 28 days of captivity, blood serum alpha-tocopherol (α-TOH) concentration was determined alongside selected metabolites (liver enzymes, total protein and fractions, cholesterol, triglycerides, and macrominerals and trace elements). Comparative feces quality and composition were also assessed. Both serum samples (0 vs. 28 days) displayed α-TOH levels below (<2 μg/mL) adequacy established for the domestic horse. Initial levels markedly (P = .020) decreased after the 4 weeks of captivity (Δ = -32.5%). Vitamin E status and ALT levels varied significantly, but serum protein fractions did not point to significant variations before and after captivity. All horses tested negative to EIA. Monitoring of vitamin E status of wild and feral herbivores may be recommendable in the context of adequate feeding practices during captivity to prevent potential deficiency or excessive depletion.

Induction of general anaesthesia by blowpipe darting in a fractious companion horse

A fractious nine-year-old, 520-kg, neutered Swiss Warmblood was presented with a history of anorexia, progressive weight loss and mild hindlimb lameness. Because of its temperament, standard physical examination was considered to be only feasible under general anaesthesia. For safety reasons, general anaesthesia was planned to be induced by blowpipe darting. Two attempts are described and discussed in the present report. The first attempt, using a combination of medetomidine and tiletamine-zolazepam, was unsuccessful. Conversely, detomidine combined with butorphanol, followed by a second dart of detomidine and tiletamine-zolazepam, proved to be adequate to induce anaesthesia. Factors that could have influenced the outcome, such as different therapeutic approach, drug protocol and dosages, stress level, or genetic mutations, are presented and discussed.

Non-surgical sterilisation methods may offer a sustainable solution to feral horse (Equus caballus) overpopulation

Feral horses are a significant pest species in many parts of the world, contributing to land erosion, weed dispersal and the loss of native flora and fauna. There is an urgent need to modify feral horse management strategies to achieve public acceptance and long-term population control. One way to achieve this is by using non-surgical methods of sterilisation, which are suitable in the context of this mobile and long-lived species. In this review we consider the benefits of implementing novel mechanisms designed to elicit a state of permanent sterility (including redox cycling to generate oxidative stress in the gonad, random peptide phage display to target non-renewable germ cells and the generation of autoantibodies against proteins essential for conception via covalent modification) compared with that of traditional immunocontraceptive approaches. The need for a better understanding of mare folliculogenesis and conception factors, including maternal recognition of pregnancy, is also reviewed because they hold considerable potential in providing a non-surgical mechanism for sterilisation. In conclusion, the authors contend that non-surgical measures that are single shot and irreversible may provide a sustainable and effective strategy for feral horse control.

Assessment of animal welfare for helicopter shooting of feral horses

Context Helicopter shooting is an effective tool for reducing feral horse (Equus caballus) populations that are considered overabundant. However, this tool has been less commonly used in recent years because of concerns about animal-welfare outcomes, which have not previously been quantified. Aims The aims of the present study were to assess the helicopter shooting of feral horses to determine (1) the duration of stress, (2) the frequency of adverse animal-welfare events and (3) the influence of explanatory variables in determining welfare outcomes. Methods We quantified the welfare outcomes of three helicopter shooting programs in central Australia during 2013 and 2015. We conducted ante-mortem observations of 937 horses and post-mortem observations of 630 horses. We measured the following three parameters to estimate the duration of stress from pursuit and the mode of death: chase time (CT), time to death (TTD) and total time (TT; CT+TTD). We quantified the frequency of adverse animal-welfare events, namely instantaneous death rate (IDR; percentage of animals for which TTD was zero), the apparent frequency of non-fatal wounding, and the frequency of bullet-wound tracts in different anatomical locations. We investigated the role of explanatory variables in determining whether or not a horse had an inferred instantaneous death. Key results For all horses, the median CT was 42s, the median TTD was 0s (median TTD for horses not killed instantaneously was 15s), and median TT was 52s. At least 1% of horses were non-fatally wounded, IDR was 63% (60–66%), and 3% (2–5%) of horses were not shot in the cranium, neck or thorax. Shooter skill was the most important determinant of whether or not a horse had an instantaneous death. Conclusions The animal-welfare outcomes of helicopter shooting appear to be similar for feral horses and feral camels (Camelus dromedarius), the only other species that has been studied using these methods, and could be refined by improving shooter skill. Implications Quantifying animal-welfare outcomes is particularly important for contentious wildlife management techniques. Wildlife managers should integrate the results of welfare studies into decision-making processes rather than excluding contentious techniques from consideration on the basis of perception.

Remote chemical immobilisation method for free-ranging Australian cattle

BACKGROUND

Many situations are encountered in Australia where the capture and restraint of free-ranging cattle (Bos taurus/Bos indicus) is required. Chemical immobilisation via darting is a potentially useful tool for managing and researching large wild herbivores; however, there is no reliable method for its application to Australian cattle. The aim of this study was to develop an efficacious, humane, cost-effective ground darting method for free-ranging cattle.

METHODS

The 30 female cattle were darted and captured on a pastoral station in north-west Australia from a vehicle. Xylazine (0.59 mg/kg) and ketamine (3.59 mg/kg) were used to capture animals and yohimbine (0.10 mg/kg) was used as an antagonist to xylazine to reduce recumbent time.

RESULTS

Cattle became recumbent at a mean time of 8 min and a mean distance of 260 m from darting. The mortality rate was zero on the day of capture and 7% at 14 days post-capture.

CONCLUSIONS

The majority of darted cattle were successfully immobilised with one dart and recovered within 30 min, with consumables costing approximately A$30 per captured animal. The technique developed represents a rapid and humane method for capturing free-ranging cattle and, with consideration for legislation surrounding use of veterinary chemicals, could be applied in many contexts across Australia.

Chemical immobilisation and rangeland species: assessment of a helicopter darting method for Australian cattle

Chemical immobilisation (darting) is increasingly being used for the capture of rangeland animals. The aim of the present study was to assess a newly developed helicopter-based chemical immobilisation method for free-ranging Australian rangeland cattle (Bos taurus and Bos indicus). Eighteen cattle were darted from a helicopter in north-western Australia in September 2015 using a combination of xylazine and ketamine, partially reversed with yohimbine. Following a recently published framework for assessing helicopter darting methods, we quantified several animal welfare measures designed to quantify the severity and duration of stress imposed by the procedures. The duration of the procedures was generally short (median total duration 41 min), but for 33% of animals total duration exceeded 60 min. Although the sample size was small, mortality rate on the day of capture was 17% (three animals) and 28% (five animals) required physical restraint to achieve recumbency. We describe this newly developed method and discuss its relatively poor animal welfare outcomes compared with other validated helicopter darting methods. Legislation restricts veterinary chemicals that may be used for food-producing species in many countries, including Australia. Chemical immobilisation regimens other than the one chosen in the present study may produce superior animal welfare outcomes but would not be compliant with legislation in Australia. As a result of these restrictions, we suggest that development of an improved helicopter darting method for Australian cattle may prove difficult. Rangeland managers should carefully consider animal welfare impacts before undertaking chemical immobilisation programs, especially for food-producing species.

An animal welfare assessment framework for helicopter darting: a case study with a newly developed method for feral horses

Context Helicopter darting (chemical immobilisation) is a very useful technique for large wild herbivores, such as feral horses (Equus caballus). There is currently no reliable framework to report on the animal welfare impacts of helicopter darting methods. Aim The aim of this study was to develop an animal welfare assessment framework for helicopter darting methods, using quantifiable parameters, and to test it with a case study using a newly developed feral horse capture technique. Methods Quantifiable animal welfare parameters were recorded for 11 feral horses captured using a traditional helicopter darting method in north-western Australia in October 2014. Welfare parameters chosen focused on quantifying the duration of procedures and the frequency of adverse events. They included chase time (CT; min) before darting, induction time (IT; min) between darting and recumbency, recumbency time (RT; min), total time (TT; CT+IT+RT; min), repeat-darting rate (animals requiring >1 dart; %), target zone accuracy rate (darts striking the intended anatomical area; %) and mortality rate (at time of capture and 14 days post-capture; %). Results Median CT was 2 min, median IT was 19 min, median RT was 16 min and median TT was 38 min. Repeat-darting rate was 45%, target zone accuracy rate was 53% and mortality rates (time of capture and 14 days post-capture) were zero. Conclusions Animal welfare parameters can be quantified for helicopter darting through estimation of the duration of procedures and the frequency of adverse events. Use of this framework will allow the identification of parameters requiring refinement for newly developed helicopter darting techniques. Implications Animal welfare parameters are particularly important for helicopter-based darting methods. Pilot studies, using quantified parameters, should be performed for newly developed capture techniques before they are approved for large-scale programs.