Developing a novel prediction model in opioid overdose using machine learning; a pilot analytical study

Background and Aims

The opioid epidemic has extended to many countries. Data regarding the accuracy of conventional prediction models including the Simplified Acute Physiologic Score (SAPS) II and acute physiology and chronic health evaluation (APACHE) II are scarce in opioid overdose cases. We evaluate the efficacy of adding quantitative electroencephalogram (qEEG) data to clinical and paraclinical data in the prediction of opioid overdose mortality using machine learning.

Methods

In a prospective study, we collected clinical/paraclinical, and qEEG data of 32 opioid-poisoned patients. After preprocessing and Fast Fourier Transform analysis, absolute power was computed. Also, SAPS II was calculated. Eventually, data analysis was performed using SAPS II as a benchmark at three levels to predict the patient's course in comparison with SAPS II. First, the qEEG data set was used alone, secondly, the combination of the clinical/paraclinical, SAPS II, qEEG datasets, and the SAPS II-based model was included in the pool of classifier models.

Results

Seven out of 32 (22%) died. SAPS II (cut-off of 50.5) had a sensitivity/specificity/positive/negative predictive values of 85.7%, 84.0%, 60.0%, and 95.5% in predicting mortality, respectively. Adding majority voting on random forest with qEEG and clinical data, improved the model sensitivity, specificity, and positive and negative predictive values to 71.4%, 96%, 83.3%, and 92.3% (not significant). The model fusion level has 40% less prediction error.

Conclusion

Considering the higher specificity and negative predictive value in our proposed model, it could predict survival much better than mortality. The model would constitute an indicator for better care of opioid poisoned patients in low resources settings, where intensive care unit beds are limited.

Comparative evaluation of electrocardiographic effects of different doses of medetomidine and xylazine in calf-camels (Camelus dromedarius)

This experimental, prospective, randomised, and blinded study aimed to perform comparative evaluation of electrocardiographic (ECG) effects of different doses xylazine and medetomidine in dromedary calves after intravenous (IV) administration. A total of twenty five clinically and paraclinically healthy male dromedary calves aged 15±2 weeks and weighing 95±5.5 kg were assigned randomly to five different groups (four experimental and one control). Groups XL and XH received a low (0.2 mg kg-1) and high (0.4 mg kg-1) dose of xylazine hydrochloride and groups ML and MH received a low (10 µg kg-1) and high (20 µg kg-1) dose of medetomidine hydrochloride once, IV. Finally, the control group (C) received normal saline in the same manner. ECG indices were evaluated on post treatment 0, 5, 10, 15, 30, 60, 90, 120 min, and 24 h. There was no significant difference in heart rate (HR) in all experimental groups at T90. HR was significantly lower after high doses than after low doses of medetomidine and xylazine at T120. HR was significantly lower in XH than in other groups of study at T24. At T90 QRS amplitude in XH was statistically lower than in control and XL groups. Analysis of P wave duration revealed that in MH and XH it was significantly longer than in ML, XL and control at T5. Duration of P wave in control group was significantly shorter than in all experimental groups from T10 to T90. RR interval duration was significantly shorter at T5 and T10 in control group compared to experimental groups. At T120, RR interval duration in MH and XH was considerably longer than that in ML, XL, and control. Compared with control group, cardiac arrhythmia scores were significantly lower than in all experimental groups from T5 to T60. At T90 and T120 in MH and XH, cardiac arrhythmia scores were significantly higher than those of XL, ML, and control. According to our findings, using low dose of medetomidine (10 µg kg-1) and xylazine (0.2 mg kg-1) was suggested in comparison with high dose of medetomidine (20 µg kg-1) and xylazine (0.4 mg kg-1) in dromedary calves with cardiac diseases in the field.

Pulsed wave Doppler echocardiographic assessment after sedation by intravenous injection of medetomidine and xylazine hydrochloride on cardiac output and systolic time intervals in one-humped camel calves (Camelus dromedarious)

BACKGROUND

Pulsed wave (PW) Doppler echocardiography provides a convenient and noninvasive tool for measuring cardiac output (CO) alternations after the administration of sedative drugs, but this is not a usual method for camelids.

AIMS

The aim of the present study was to investigate the changes of the left and right ventricular outflow tracts (LVOT and RVOT), CO, and systolic time intervals following the intravenous (IV) injection of medetomidine (M) and xylazine (X) using PW Doppler echocardiography.

METHODS

Twenty apparently healthy immature male one-humped camels (Camelus dromedarious) were selected and divided into four groups (five animals per group). Medetomidine and X were injected to the left jugular vein at two different doses of 10 and 20 μg/kg, and 0.2 and 0.4 mg/kg, respectively. Effects on echocardiographic parameters were assessed at 4 intervals: before, 3, 60, and 120 min after drug administrations.

RESULTS

Velocity time integrity (VTI), maximum/mean flow velocity (Vmax and Vmean) and maximum/mean pressure gradient (PGmax and PGmean) decreased in aortic and pulmonic valves. Left ventricular ejection time (LVET) and LVET + pre ejection period (PEP) decreased and PEP and PEP/LVET increased in all groups except the low dose X group, 3 min after drug administration (P<0.05). The least values of VTI, velocity (V), PG and CO were observed after 60 min in the low dose X group (P<0.05).

CONCLUSION

A relationship was found between the intensity and the duration of changes in cardiac parameters and both types and dosages of the injected drugs. We concluded that X and M have transient depressor effects on the ventricular outflow tract and CO of healthy camels.

Investigation of ischemic and demyelinating lesions by cerebral vasoreactivity based on transcranial Doppler sonography: a comparative study

PURPOSE

Variations of cerebral blood flow in response to hypoxia and hyperoxia in different disease conditions can provide new insights into disease etiopathogenesis. This study aimed to determine the characteristics of cerebral vasoreactivity for ischemia and demyelination.

MATERIALS AND METHODS

This case-control study included: 28 patients with lacunar infarctions verified by history, physical examination, and MRI; 28 age- and sex-matched healthy controls; 28 patients with relapsing-remitting multiple sclerosis (MS), based on McDonald criteria; and 28 age- and sex-matched healthy controls for the MS group. Transcranial Doppler sonography was undertaken in all subjects to calculate the mean flow velocity (MFV) of the right middle cerebral artery (MCA) and, after a breath-holding (BH) maneuver, the breath-holding index (BHI) was determined.

RESULTS

There was no significant difference of BHI and changes of MFV of the MCA in MS patients compared to controls (1.02 ± 0.4 vs 1.02 ± 0.3, p = 0.993; and 16.8 ± 8.1 vs 11.3 ± 10.8, p = 0.057). BHI in patients with lacunar infarctions was significantly lower (0.8 ± 0.4 vs 1.2 ± 0.3, p < 0.001) compared to controls. The BHI (p = 0.040) and variations of MFV of MCA (p = 0.007) in MS patients were significantly higher than in patients with lacunar infarctions. The vasoreactivity of demyelinating lesions was higher than that of ischemic ones.

CONCLUSION

Therefore, cerebral vasoreactivity determined by transcranial Doppler could be utilized for differentiating demyelinating from ischemic lesions.

Ultrastructural and morphometrical changes of mice ovaries following experimentally induced copper poisoning

BACKGROUND

Copper (Cu) is an essential trace element involved in normal reproduction but its overexposure may produce some detrimental effects. The aim of this study was to investigate the effects of copper sulfate poisoning on morphometery of mice ovarian structures and probable intracellular changes.

METHODS

Thirty mature female mice were randomly allocated to control and two treatment groups. In treatment groups, two different doses of copper sulfate including 100 mg/kg and 200 mg/kg in 0.2 cc were applied once a day for 35 consecutive days by gavage. Control animals received normal saline using the same volume and similar method. Animals from each experimental group were sacrificed 14 and 35 days after the beginning of drug administration and the left ovaries were removed for stereological evaluations by light microscopy and right ovaries were obtained for preparing electron microscopic sections.

RESULTS

The morphometrical results showed that only the number of antral follicles was decreased by 100 mg/kg copper sulfate on day 14 compared to the control group (P=0.043). Hence, higher copper dose or longer consumption period significantly reduced different classes of follicles and corpora lutea. With 100 mg/kg copper sulfate some mild ultrastructural cell damages such as decrease of zona pellucida thickness, limited vacuolated areas and nuclear envelop dilation were seen on day 14. Higher or longer Cu administration produced more detrimental effects including more vacuolated areas, presence of secondary lysosomes, irregularity in cell shape and segmented nuclei with condensed and marginated chromatin and more enlarged and damaged mitochondria.

CONCLUSION

New evidences of early as well as late intracellular damages of copper has been presented by accurate stereological and ultrastructural methods. Antral follicles was the most susceptible cells with the lower and shorter copper consumption and long term or higher dose of copper affected the whole of ovarian structures.

Polioencephalomalacia associated with closantel overdosage in a goat

This report describes clinical and pathological findings associated with closantel (a halogenated salicylanilide anthelmintic) overdosage in a 3-year-old goat. The clinical signs included blindness, incoordination, ataxia, depression of the palpebral and pupillary reflexes, and recumbency. No gross lesions were noted in tissue or organs at necropsy, but microscopic lesions were seen in nervous tissue and hepatic cells. Polioencephalomalacia was clearly evident. Bilaterally symmetrical status spongiosus of the white matter of the brain, bilateral laminar necrosis, microcavitations, ischaemic cell change and severe degeneration of the cerebellum were seen in nervous tissue. Fatty change and hydropic degeneration in the liver and hepato-cellular degeneration were observed histologically.