Sedation with dexmedetomidine-butorphanol or xylazine-butorphanol continuous intravenous infusions during unilateral ovariectomy in standing donkeys.

BACKGROUND: Intravenous infusions of alpha-2 adrenoceptor sedatives and opioids can potentially facilitate surgery in donkeys while standing. Literature on this subject matter is scant. OBJECTIVES: Evaluation of efficacy of sedation from α2 -adrenoceptors (dexmedetomidine or xylazine) and butorphanol during ovariectomy in standing donkeys. STUDY DESIGN: Randomised, masked in vivo experiment. METHODS: Thirteen female donkeys were sedated with butorphanol (0.05 mg/kg bwt followed by 0.05 mg/kg bwt/h) IV. Concomitantly, 6 of the 13 jennies were sedated with dexmedetomidine 2.5 mcg/kg bwt followed by 2.5 mcg/kg bwt/h (Dex-B group), while seven jennies were sedated with xylazine 0.5 mg/kg bwt followed by 0.5 mg/kg bwt/h (Xyl-B group). A line block of the left flank and an infiltration block around uterine ligament were performed with lidocaine. While the jennies underwent ovariectomies standing, sedation scores and head height above ground were assessed at 2 and 10 min after sedative boluses and every 10 min thereafter. If sedation was too light or too deep, the dose of dexmedetomidine or xylazine was increased or decreased by 25% of the original infusion rate, while butorphanol infusion rate was constant. Physiological parameters were measured. Normally distributed data were compared using the two-sample t test while repeatedly measured data were tested for differences between and within groups using repeated measures analysis of variance (ANOVA) by ranks followed by a Wilcoxon test with Tukey Honest Significant Difference for multiple testing. Statistical significance was set at p < 0.05. RESULTS: Both Dex-B and Xyl-B caused moderate to marked sedation adequate for ovariectomy in donkeys. Evident sedation was absent by 60 min of termination of infusions. No adverse physiological effects were observed. MAIN LIMITATIONS: Study on ovariectomy cases only, no pharmacokinetic profiling. CONCLUSIONS: Dexmedetomidine or xylazine and butorphanol sedation is feasible for ovariectomy in standing donkeys.

Overall good agreement of smartphone-based and standard base-apex electrocardiography in healthy sheep.

OBJECTIVE: To assess and compare the quality of smartphone ECG tracings to standard (base-apex) ECG tracings and assess agreement of ECG parameters between smartphone-based ECG and standard ECG. ANIMALS: 25 rams. PROCEDURES: The rams were consecutively examined with standard ECG and smartphone-based ECG (KardiaMobile; AliveCor Inc) after physical examination. ECGs were compared for quality score, heart rate, and ECG waves, complexes, and intervals. Quality scores were based on the presence or absence of baseline undulation and tremor artifacts using a 3-point scoring system (lowest possible = 0; highest possible = 3). A lower score was indicative of a better-quality ECG. RESULTS: Smartphone-based ECGs were interpretable in 65% of cases, while 100% of standard ECGs were interpretable. Standard ECG quality was superior to smartphone-based ECG quality, with no agreement in the quality between devices (κ coefficient, -0.0062). There was good agreement for heart rate with mean difference 2.86 beats/min (CI, -3.44 to 9.16) between the standard and smartphone ECGs. Good agreement was observed for P wave amplitude with mean difference 0.02 mV (CI, -0.01 to 0.05), QRS duration with mean difference -10.5 ms (CI, -20.96 to -0.04), QT interval with mean difference -27.14 ms (CI, -59.36 to 5.08), T wave duration with mean difference -30.00 ms (CI, -66.727 to 6.727), and T wave amplitude with mean difference -0.07 mV (CI, -0.22 to 0.08) between the 2 devices. CLINICAL RELEVANCE: Our findings indicate good agreement between standard and smartphone ECG for most parameters, although 35% of smartphone ECGs were uninterpretable.

Supervised Kohonen Self-Organizing Maps of Acute Asthma from Air Pollution Exposure.

There are unanswered questions with regards to acute respiratory outcomes, particularly asthma, due to environmental exposures. In contribution to asthma research, the current study explored a computational intelligence paradigm of artificial neural networks (ANNs) called self-organizing maps (SOM). To train the SOM, air quality data (nitrogen dioxide, sulphur dioxide and particulate matter), interpolated to geocoded addresses of asthmatics, were used with clinical data to classify asthma outcomes. Socio-demographic data such as age, gender and race were also used to perform the classification by the SOM. All pollutants and demographic traits appeared to be important for the correct classification of asthma outcomes. Age was more important: older patients were more likely to have asthma. The resultant SOM model had low quantization error. The study concluded that Kohonen self-organizing maps provide effective classification models to study asthma outcomes, particularly when using multidimensional data. SO2 was concluded to be an important pollutant that requires strict regulation, particularly where frail subpopulations such as the elderly may be at risk.

Factors associated with the successful completion of a substance rehabilitation programme at a psychiatric training hospital.

BACKGROUND: Comorbid psychiatric and substance use disorders are common and present several treatment challenges. AIM: The aim of this study was to determine which patient and substance factors are associated with the completion of a substance rehabilitation programme in psychiatric inpatients. SETTING: The study was conducted at the Substance Rehabilitation Unit (SRU) at Weskoppies Hospital, a psychiatric training hospital in South Africa, which offers a 6-week programme at the hospital for psychiatric inpatients. METHODS: This descriptive, retrospective hospital-based study was carried out comparing completers and non-completers of the SRU programme with respect to patient and substance factors. All patients accepted into the SRU during 2013-2014 were included (n = 119). Data were collected over a year (2016-2017) from the clinical files, SRU referral forms, SRU attendance register, hospital computerised demographic records, nursing notes and administration files using a data collection sheet designed by the researchers for this study. Comparison between completers and non-completers was performed using Chi-Square or Fisher's Exact tests. RESULTS: The SRU accepted 119 patients from January 2013 to December 2014. The majority of the sample were involuntary patients (n = 39), 30-49 years old (n = 57), male (n = 89), unmarried (n = 112), never having received a disability grant (n = 27), unemployed (n = 96) and with a Grade 8-11 education (n = 49). Substance-induced psychotic disorders (n = 39), schizophrenia (n = 29) and bipolar disorders (n = 22) were found to be common. Frequent medical comorbidities included head injury (n = 27), cardiovascular disease (n = 18) and HIV reactivity (n = 7). Cannabis (n = 98), alcohol (n = 94) and nicotine (n = 90) were the most frequently used substances. Level of education (p = 0.004), disability grant status (p = 0.004), Nyaope use (p = 0.001) and nicotine use (p = 0.049) were statistically seen to be significantly associated with completion. Psychiatric diagnoses and general medical comorbidity were not associated with completion. CONCLUSIONS: This study has yielded several results in areas that have not yet been well researched in South Africa. Risk factors for non-completion may include lower levels of education, being on a disability grant and using Nyaope or nicotine, but may vary in different settings. Future research should focus on identifying further factors that may affect completion of substance rehabilitation in psychiatric inpatients, the role of disability grants in patients with co-occurring disorders and the effect of Nyaope and nicotine use on treatment outcomes in this population. Effective and accessible interventions to assist vulnerable patients also need to be identified.

Maternal factors contributing to low birth weight deliveries in Tshwane District, South Africa.

BACKGROUND: Low birth weight continues to be a main cause of child morbidity and mortality. Low birth weight can cause complications in adult life, and is therefore a public health concern. In this study, we determined the maternal factors that contribute to low birth weight (LBW) deliveries in Tshwane District, South Africa. METHODS: We conducted a case control study of 1073 randomly selected mothers who delivered babies in four hospitals in the district. We reviewed antenatal and maternity registers to obtain information about the mothers and their offspring. We fitted a multiple logistic regression to examine relationships between possible factors associated with LBW. RESULTS: From the total sample of mothers (n = 1073), 77% (n = 824) were adult women, aged 20 to 35 years. Of the adult mothers, 38.54% (n = 412) delivered low birth weight (LBW) infants. The mean gestational age and weight of all infants at birth was 37.16 weeks (SD 2.92) and 2675.48 grams (SD 616.16) respectively. LBW was associated with prematurity, odds ratio (OR) 7.15, 95% confidence interval (CI) 5.18 to 9.89; premature rupture of membranes OR 7.33, 95% CI 2.43 to 22.12 and attending fewer than five antenatal care (ANC) visits OR 1.30, 95% CI 1.06 to 1.61. Male infants were less likely to be LBW, in this population. CONCLUSION: Women who attended fewer than five ANC visits were predisposed to give birth to low birth weight babies. Mothers should be encouraged to attend ANC visits to detect adverse events like premature rupture of membranes and premature labour timeously.

The minimum infusion rate of alfaxalone during its co-administration with lidocaine at three different doses by constant rate infusion in goats.

OBJECTIVE: To determine the minimum infusion rate (MIR) of alfaxalone required to prevent purposeful movement in response to standardized stimulation while co-administered with lidocaine at three different doses by constant infusion rate infusion (CRI) in goats. STUDY DESIGN: Prospective, blinded, randomized crossover, experimental. ANIMALS: A total of eight healthy goats: four does and four wethers. METHODS: Anaesthetic induction was with lidocaine at 1 mg kg-1 [low dose of lidocaine (L-Lid)], 2 mg kg-1 [moderate dose (M-Lid)] or 4 mg kg-1 [high dose (H-Lid)] and alfaxalone at 2 mg kg-1. Anaesthetic maintenance was with alfaxalone initially at 9.6 mg kg-1 hour-1 combined with one of three lidocaine treatments: 3 mg kg-1 hour-1 (L-Lid), 6 mg kg-1 hour-1 (M-Lid) or 12 mg kg-1 hour-1 (H-Lid). The MIR of alfaxalone was determined by testing for responses to a stimulation in the form of clamping on a digit with a Vulsellum forceps every 30 minutes during lidocaine CRI. Basic cardiopulmonary parameters were measured. RESULTS: The alfaxalone MIRs were 8.64 (6.72-10.56), 6.72 (6.72-8.64) and 6.72 (6.72-6.72) mg kg-1 hour-1 during L-Lid, M-Lid and H-Lid, respectively, without any significant differences among treatments. Compared to the initial rate of 9.6 mg kg-1 hour-1, these reductions in MIR are equivalent to 10, 30 and 30%, respectively. Significant increases in heart rate (HR) and arterial carbon dioxide partial pressure (PaCO2) and decreases in arterial haemoglobin saturation (SaO2), arterial oxygen partial pressure (PaO2) and respiratory frequency (fR) immediately after induction were observed during all lidocaine treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Lidocaine reduces the alfaxalone MIR by up to 30% with a tendency towards a plateauing in this effect at high CRIs. Immediate oxygen supplementation might be required to prevent hypoxaemia.

Determination of the minimum infusion rate of alfaxalone during its co-administration with fentanyl at three different doses by constant rate infusion intravenously in goats.

OBJECTIVE: To determine the minimum infusion rate (MIR) of alfaxalone required to prevent purposeful movement of the extremities in response to standardized noxious stimulation during its co-administration with fentanyl at three different doses by constant rate infusion (CRI) intravenously (IV) in goats. STUDY DESIGN: Prospective, blinded, randomized crossover, experimental. ANIMALS: Eight healthy goats; four does and four wethers. METHODS: For induction of anaesthesia, a bolus of fentanyl was administered at 0.005 mg kg(-1) (LFent), 0.015 mg kg(-1) (MFent) or 0.03 mg kg(-1) (HFent) followed by alfaxalone at 2.0 mg kg(-1) . For maintenance, the goats received alfaxalone at an initial infusion rate of 9.6 mg kg(-1)  hour(-1) and one of three fentanyl treatments: 0.005 mg kg(-1)  hour(-1) (LFent), 0.015 mg kg(-1)  hour(-1) (MFent) or 0.03 mg kg(-1) hour(-1) (HFent). The MIR of alfaxalone was determined during fentanyl CRI by testing for responses to stimulation (clamping on a digit with Vulsellum forceps) every 30 minutes. Some cardiopulmonary parameters were measured. RESULTS: The alfaxalone MIR median (range) was 6.7 (6.7-8.6), 2.9 (1.0-6.7) and 1.0 (1.0-4.8) mg kg(-1)  hour(-1) during LFent, MFent and HFent, respectively. Alfaxalone MIR was significantly lower during MFENT and HFENT compared to LFENT. Significantly low oxygen haemoglobin saturation (SaO2 ) and arterial oxygen partial pressure (PaO2 ), observed 2 minutes into anaesthesia after all fentanyl treatments, were the most remarkable adverse cardiopulmonary effects observed. Recovery from anaesthesia was severely affected by high doses of fentanyl with excitatory behavioural signs predominant for up to 2 hours post-administration after MFent and HFent. CONCLUSIONS AND CLINICAL RELEVANCE: Fentanyl reduces alfaxalone MIR in goats in a dose-dependent manner. Immediate oxygen supplementation after induction of general anaesthesia is recommended to prevent hypoxaemia. Doses of fentanyl equal to or greater than 0.015 mg kg(-1)  hour(-1) tend to be associated with severe excitatory behaviour and should be avoided when fentanyl is administered to goats.

Determination of the minimum infusion rate of propofol required to prevent purposeful movement of the extremities in response to a standardized noxious stimulus in goats.

OBJECTIVE: To determine the minimum infusion rate (MIR) of propofol required to prevent purposeful movement in response to a standardized stimulus in goats. STUDY DESIGN: Prospective, experimental study. ANIMALS: Eight healthy goats (four does, four wethers). METHODS: Anaesthesia was induced with 4 mg kg(-1) propofol intravenously (IV). A continuous IV infusion of propofol at 0.6 mg kg(-1)  minute(-1) was initiated immediately to maintain anaesthesia. Following endotracheal intubation, goats breathed spontaneously via a circle breathing system delivering supplementary oxygen. The initial propofol infusion rate was maintained for 30 minutes before responses to noxious stimulation provided by clamping the proximal part of the claw with a Vulsellum forceps for 60 seconds were tested. In the presence or absence of purposeful movements of the extremities, the infusion rate was increased or reduced by 0.1 mg kg(-1)  minute(-1) and held constant for 30 minutes before claw clamping was repeated. The propofol MIR for each goat was calculated as the mean of the infusion rates that allowed and abolished movement. Basic cardiopulmonary parameters were monitored, recorded and tested for statistical significance using Wilcoxon's signed rank test with Bonferroni adjustment for multiple testing. The quality of recovery from anaesthesia was assessed and scored. RESULTS: The median MIR of propofol was 0.45 mg kg(-1)  minute(-1) (range: 0.45-0.55 mg kg(-1)  minute(-1) ). Induction and recovery were free of adverse behaviour. No statistically significant cardiopulmonary changes in comparison with baseline were observed, but clinically relevant hypoxaemia at 2 minutes after induction of anaesthesia was consistently observed. Chewing during anaesthesia was observed in three goats. Median times to extubation and standing were 3 minutes (range: 2-6 minutes) and 10 minutes (range: 7-21 minutes), respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Propofol induction and maintenance of general anaesthesia minimally compromise cardiopulmonary function when oxygen is supplemented in goats.

Determination of the minimum infusion rate (MIR) of alfaxalone required to prevent purposeful movement of the extremities in response to a standardised noxious stimulus in goats.

OBJECTIVE: To determine the minimum infusion rate (MIR) of alfaxalone required to prevent purposeful movement of the extremities in response to noxious stimulation. STUDY DESIGN: Prospective, experimental. ANIMALS: Eight healthy goats; four does and four wethers. METHODS: Anaesthesia was induced with alfaxalone 3 mg kg(-1) intravenously (IV). A continuous IV infusion of alfaxalone, initially at 0.2 mg kg(-1)  minute(-1) , was initiated. Following endotracheal intubation the goats breathed spontaneously via a circle breathing circuit delivering supplementary oxygen. The initial infusion rate was maintained for 30 minutes before testing for responses. The stimulus was clamping on the proximal (soft) part of one digit of the hoof with Vulsellum forceps for 60 seconds. In the absence or presence of purposeful movement of the extremities, the infusion rate was reduced or increased by 0.02 mg kg(-1)  minute(-1) and held constant for 30 minutes before claw-clamping again. Alfaxalone MIR was calculated as the mean of the infusion rates that allowed and abolished movement. Cardio-respiratory parameters were measured. Recovery from general anaesthesia was timed and quality scored. Results are presented as median (range). RESULTS: The MIR of alfaxalone was 0.16 (0.14-0.18) mg kg(-1)  minute(-1) or 9.6 (8.4-10.8) mg kg(-1)  hour(-1) . Induction of and recovery from anaesthesia were excitement-free. Cardio-respiratory changes were minimal, although compared to baseline HR increased, and at 2 minutes post-induction, (prior to oxygen supplementation), PaO2 decreased significantly from 84 (80-88) to 70 (51-72) mmHg [11.2 (10.7-11.7) to 9.3 (6.8-9.6) kPa]. Sporadic muscle twitches, unrelated to depth of anaesthesia, were observed during the period of general anaesthesia. Time (minutes) to sternal recumbency and standing were 4.0 (3.0-10.0) and 41.5 (25.0-57.0) respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Alfaxalone can be used for total intravenous anaesthesia (TIVA) in goats and is associated with minimal adverse effects. Oxygen supplementation is advised, especially when working at higher altitudes.

The effects of midazolam and butorphanol, administered alone or combined, on the dose and quality of anaesthetic induction with alfaxalone in goats.

Goats are rarely anaesthetised; consequently, scant information is available on the efficacy of anaesthetic drugs in this species. Alfaxalone is a relatively new anaesthetic agent, of which the efficacy in goats has not yet been studied. In this study, the sedative and alfaxalone sparing effects of midazolam and butorphanol, administered alone or concomitantly, in goats were assessed. Eight clinically healthy goats, four does and four wethers, were enlisted in a randomised crossover manner to receive intramuscular sedative treatments consisting of saline 0.05 mL/kg, or midazolam 0.30 mg/kg, or butorphanol 0.10 mg/kg, or a combination of midazolam 0.30 mg/kg with butorphanol 0.10 mg/kg before intravenous induction of general anaesthesia with alfaxalone. Following induction, the goats were immediately intubated and the quality of anaesthesia and basic physiological cardiorespiratory and blood-gas parameters were assessed until the goats had recovered from anaesthesia. The degree of sedation, quality of induction and recovery were scored. When compared with saline (3.00 mg/kg), midazolam,administered alone or with butorphanol, caused a statistically significant increased level of sedation and a reduction in the amount of alfaxalone required for induction (2.00 mg/kg and 1.70 mg/kg, respectively). Butorphanol alone (2.30 mg/kg) did not cause significant changes in level of sedation or alfaxalone-induction dose. During induction and recovery, the goats were calm following all treatments, including the control group. Cardiorespiratory and blood-gas parameters were maintained within clinically acceptable limits. The present study showed that midazolam, administered alone or combined with butorphanol, produces a degree of sedation that significantly reduces the dose of alfaxalone required for induction of general anaesthesia in goats, without causing any major adverse cardiorespiratory effects.

Effects of propofol on isoflurane minimum alveolar concentration and cardiovascular function in mechanically ventilated goats.

OBJECTIVE: To evaluate the effects of propofol, on isoflurane minimum alveolar concentration (MAC) and cardiovascular function in mechanically ventilated goats. STUDY DESIGN: Prospective, randomized, crossover experimental study. ANIMALS: Six goats, three does and three wethers. METHODS: General anaesthesia was induced with isoflurane in oxygen. Following endotracheal intubation, anaesthesia was maintained with isoflurane in oxygen. Intermittent positive pressure ventilation was applied. Baseline isoflurane MAC was determined, the noxious stimulus used being clamping a claw. The goats then received, on separate occasions, three propofol treatments intravenously: bolus of 0.5 mg kg(-1) followed by a constant rate infusion (CRI) of 0.05 mg kg(-1) minute(-1) (treatment LPROP); bolus of 1.0 mg kg(-1) followed by a CRI of 0.1 mg kg(-1) minute(-1) (treatment MPROP), bolus of 2.0 mg kg(-1) followed by a CRI of 0.2 mg kg(-1) minute(-1) (treatment HPROP). Isoflurane MAC was re-determined following propofol treatments. Plasma propofol concentrations at the time of MAC confirmation were measured. Cardiopulmonary parameters were monitored throughout the anaesthetic period. Quality of recovery was scored. The Friedman test was used to test for differences between isoflurane MACs. Medians of repeatedly measured cardiovascular parameters were tested for differences between and within treatments using repeated anova by ranks (p<0.05 for statistical significance). RESULTS: Isoflurane MAC [median (interquartile range)] was 1.37 (1.36-1.37) vol%. Propofol CRI significantly reduced the isoflurane MAC, to 1.15 (1.08-1.15), 0.90 (0.87-0.93) and 0.55 (0.49-0.58) vol% following LPROP, MPROP and HPROP treatment, respectively. Increasing plasma propofol concentrations strongly correlated (Spearman rank correlation) with decrease in MAC (Rho=0.91). Cardiovascular function was not affected significantly by propofol treatment. Quality of recovery was satisfactory. CONCLUSIONS AND CLINICAL RELEVANCE: In goats, propofol reduces isoflurane MAC in a dose-dependent manner with minimal cardiovascular effects.

Total intravenous anaesthesia (TIVA) with propofol-fentanyl and propofol-midazolam combinations in spontaneously-breathing goats.

OBJECTIVE: To compare the efficacy and cardiopulmonary effects of propofol and fentanyl, with propofol and midazolam for total intravenous anaesthesia. STUDY DESIGN: Prospective, randomized, crossover experimental study. ANIMALS: Six goats; three does and three wethers. METHODS: Goats received either fentanyl 0.02 mg kg(-1) (treatment FP) or midazolam 0.3 mg kg(-1) (treatment MP) intravenously. One minute later anaesthesia was induced with propofol, then maintained by constant rate infusion of propofol 12.0 mg kg(-1) hour(-1) and fentanyl 0.02 mg kg(-1) hour(-1) (treatment FP) or propofol 12.0 mg kg(-1) hour(-1) and midazolam 0.3 mg kg(-1) hour(-1) (treatment MP) for 90 minutes. Response to noxious stimulus was tested every 10 minutes and propofol dose adjusted to prevent purposeful movement. Cardiopulmonary parameters were measured continuously, and arterial blood-gas analysis performed intermittently. Recovery was timed and quality scored. Results are presented as median (IQR). RESULTS: Differences in the propofol induction dose [4.00 (3.96-4.01) and 3.97 (3.91-4.00) mg kg(-1) for treatments FP and MP, respectively] were not significant. Quality of induction in both groups was smooth. The median propofol dose for maintenance was less (p = 0.004) with treatment FP (12.0 mg kg(-1) hour(-1) than MP (18.0 mg kg(-1) hour(-1). Cardiopulmonary function was well maintained with both treatments. Recovery times in minutes from the end of anaesthetic infusion for treatments FP and MP respectively were; to extubation 3.0 (3.0-3.0) and 4.5 (3.3-5.0); to sternal position, 4.5 (3.3-5.0) and 5.0 (5.0-6.5) and to standing 13.0 (10.3-15.0) and 15.0 (11.3-17.3). Quality of recovery was acceptable in both groups, but abnormal behavioural signs were observed after treatment FP. CONCLUSIONS AND CLINICAL RELEVANCE: Total intravenous anaesthesia with propofol and fentanyl or propofol and midazolam, at the doses studied, in spontaneously-breathing, oxygen-supplemented goats is practicable. Recovery from the fentanyl-propofol combination is not always smooth.