scholarly journals Differential effects of four intramuscular sedatives on cardiorespiratory stability in juvenile guinea pigs (Cavia porcellus)

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259559
Author(s):  
Ryan P. Sixtus ◽  
Cholawat Pacharinsak ◽  
Clint L. Gray ◽  
Mary J. Berry ◽  
Rebecca M. Dyson

Background Non-invasive physiological monitoring can induce stress in laboratory animals. Sedation reduces the level of restraint required, thereby improving the validity of physiological signals measured. However, sedatives may alter physiological equilibrium introducing unintended bias and/or, masking the experimental outcomes of interest. We aimed to investigate the cardiorespiratory effects of four short-acting sedatives in juvenile guinea pigs. Method 12 healthy, 38 (26–46) day-old Dunkin Hartley guinea pigs were included in this blinded, randomised, crossover design study. Animals were sedated by intramuscular injection using pre-established minimum effective doses of either alfaxalone (5 mg/kg), diazepam (5 mg/kg), ketamine (30 mg/kg), or midazolam (2 mg/kg) administered in random order with a minimum washout period of 48 hours between agents. Sedative depth, a composite score comprised of five assessment criteria, was observed every 5-min from dosing until arousal. Physiological monitoring of cardiorespiratory status included measures of heart rate, blood pressure, respiratory rate, and peripheral microvascular perfusion. Results Ketamine and alfaxalone were most effective in inducing stable sedation suitable for physiological monitoring, and diazepam less-so. Midazolam was unsuitable due to excessive hypersensitivity. All sedatives significantly increased heart rate above non-sedated control rates (P<0.0001), without altering blood pressure or microvascular perfusion. Alfaxalone and ketamine reduced respiratory rate relative to their control condition (P<0.0001, P = 0.05, respectively), but within normative ranges. Conclusion Ketamine and alfaxalone are the most effective sedatives for inducing short duration, stable sedation with minimal cardiorespiratory depression in guinea pigs, while diazepam is less-so. However, alfaxalone is the most appropriate sedative for longitudinal studies requiring multiple physiological timepoints.

2021 ◽  
Author(s):  
A.O. Shvetc ◽  
I.A. Shperling ◽  
A.V. Krupin ◽  
P.A. Romanov ◽  
N.N. Matveeva

The experiment was carried out on male pigs, which in the operating room were simulated with acute blood loss (air temperature 23oC). Then the animals were placed in a climatic chamber (minus 50 ° C) for 10 minutes. Then the temperature in the climatic chamber was raised to minus 10 ° C and the introduction of the test solutions to the animals began. It was found that in both groups there were similar indicators of blood pressure. The heart rate and respiratory rate in animals in the group with the experimental solution based on polyglucin derivatives were lower than in the group with the solution based on dextran. Key words: external general cooling, pigs, blood pressure, heart rate, respiratory rate, infusion solution.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Elisa Mejía-Mejía ◽  
James M. May ◽  
Mohamed Elgendi ◽  
Panayiotis A. Kyriacou

AbstractHeart rate variability (HRV) utilizes the electrocardiogram (ECG) and has been widely studied as a non-invasive indicator of cardiac autonomic activity. Pulse rate variability (PRV) utilizes photoplethysmography (PPG) and recently has been used as a surrogate for HRV. Several studies have found that PRV is not entirely valid as an estimation of HRV and that several physiological factors, including the pulse transit time (PTT) and blood pressure (BP) changes, may affect PRV differently than HRV. This study aimed to assess the relationship between PRV and HRV under different BP states: hypotension, normotension, and hypertension. Using the MIMIC III database, 5 min segments of PPG and ECG signals were used to extract PRV and HRV, respectively. Several time-domain, frequency-domain, and nonlinear indices were obtained from these signals. Bland–Altman analysis, correlation analysis, and Friedman rank sum tests were used to compare HRV and PRV in each state, and PRV and HRV indices were compared among BP states using Kruskal–Wallis tests. The findings indicated that there were differences between PRV and HRV, especially in short-term and nonlinear indices, and although PRV and HRV were altered in a similar manner when there was a change in BP, PRV seemed to be more sensitive to these changes.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 914.2-914
Author(s):  
S. Boussaid ◽  
M. Ben Majdouba ◽  
S. Jriri ◽  
M. Abbes ◽  
S. Jammali ◽  
...  

Background:Music therapy is based on ancient cross-cultural beliefs that music can have a “healing” effect on mind and body. Research determined that listening to music can increase comfort and relaxation, relieve pain, lower distress, reduce anxiety, improve positive emotions and mood, and decrease psychological symptoms. Music therapy has been used greatly in various medical procedures to reduce associated anxiety and pain. Patients have a high level of anxiety when they are in the hospital, this is the case of patients with rheumatic diseases who consult regularly to have intravenous infusion of biological therapies.Objectives:The purpose of this study was to examine the effectiveness of music therapy on pain, anxiety, and vital signs among patients with chronic inflammatory rheumatic diseases during intravenous infusion of biological drugs.Methods:Fifty patients were divided into two groups: The experimental group G1 (n=25) received drug infusion while lestening to soft music (30 minutes); and the control group G2 (n=25) received only drug infusion. Measures include pain, anxiety, vital signs (blood pressure, heart rate and respiratory rate). The pain was measured using visual analogic scale (VAS). The state-trait anxiety inventory (STAI) was used for measuring anxiety, low anxiety ranges from 20 to 39, the moderate anxiety ranges from 40 to 59, and high anxiety ranges from 60 to 80. Vital signs (systolic blood pressure [SBP], diastolic blood pressure [DBP], heart rate [HR], and respiratory rate [RR]) were measured before, during and immediately after the infusion.Statistical package for social sciences (SPSS) was used for analysis.Results:The mean age in G1 was 44.45 years (26-72) with a sex ratio (M/F) of 0.8. Including the 25 patients, 12 had rheumatoid arthritis, 10 had ankylosing spondylitis and 3 had psoriatic arthritis. The mean disease duration was 8 years. In G2, the mean age was 46 years (25-70) with a sex ratio (M/F) of 0.75, 12 had rheumatoid arthritis, 11 had ankylosing spondylitis and 2 had psoriatic arthritis. The mean disease duration was 7.5 years. The biological drugs used were: Infliximab in 30 cases, Tocilizumab in 12 cases and Rituximab in 8 cases.Before the infusion, the patients of experimental group had a mean VAS of 5/10±3, a mean STAI of 50.62±6.01, a mean SBP of 13.6 cmHg±1.4, a mean DBP of 8.6 cmHg±1, a mean HR of 85±10 and a mean RR of 18±3. While in control group the mean VAS was 5.5±2, the mean STAI was 50.89±5.5, the mean SBP was 13.4±1.2, the mean DBP was 8.8±1.1, the mean HR was 82±8 and the mean RR was 19±2.During the infusion and after music intervention in G1, the mean STAI became 38.35±5 in G1 versus 46.7±5.2 in G2 (p value=0.022), the mean SBP became 12.1±0.5 in G1 versus 13±1 in G2 (p=0.035), the mean DBP became 8.1±0.8 in G1 versus 8.4±0.9 in G2 (p=0.4), the mean HR became 76±9 in G1 versus 78±7 in G2 (p=0.04) and the mean RR became 17.3±2.1 in G1 versus 18.2±1.7 in G2 (p=0.39).This study found a statistically significant decrease in anxiety, systolic blood pressure and heart rate in patients receiving music interventions during biological therapies infusion, but no significant difference were identified in diastolic blood pressure and respiratory rate.Conclusion:The findings provide further evidence to support the use of music therapy to reduce anxiety, and lower systolic blood pressure and heart rate in patients with rheumatic disease during biological therapies infusion.References:[1] Lin, C., Hwang, S., Jiang, P., & Hsiung, N. (2019).Effect of Music Therapy on Pain After Orthopedic Surgery -A Systematic review and Meta-Analysis. Pain Practice.Disclosure of Interests:None declared


2006 ◽  
Vol 75 (1) ◽  
pp. 3-12 ◽  
Author(s):  
J. Mokrý ◽  
T. Remeňová ◽  
K. Javorka

The purpose of the study was to evaluate the changes of respiratory rate, systemic blood pressure and heart rate variability parameters (HRV) during orthostasis in anaesthetized rabbits. Furthermore, these changes were influenced by affecting the renin-angiotensin-aldosterone (RAA) system and autonomic nervous system (ANS) to study the mechanisms participating in activity of spectral frequency bands of HRV in rabbits. Ten adult rabbits (Chinchilla) were anaesthetized by ketamine and flunitrazepam. The systemic blood pressure, tidal volume and respiratory rate were measured. HRV was evaluated by microcomputer system VariaPulse TF3E. The R-R intervals were derived from the electrocardiogram signal from subcutaneous needle electrodes. The evaluation of HRV in very low (VLF; 0.01-0.05 Hz), low (LF; 0.05-0.15 Hz) and high frequency bands (HF; 0.15-2.0 Hz) was made and parameters of frequency and time analysis were calculated. The measurements were made in horizontal (supine) position, in orthostasis (the angle of 60 °) and again in supine position before and after enalapril (0.5 mg/kg b.w.), metipranolol (0.2 mg/kg b.w.), and after subsequent bilateral cervical vagotomy. The orthostasis in anaesthetized rabbits is accompanied by depression of respiratory rate reversed only by vagotomy. Furthermore, decrease of systemic blood pressure, unchanged heart rate and increased characteristics of heart rate variability were found, with predominant increase of spectral power in LF and VLF bands. This elevation can be eliminated only by complete blockade of ANS. Although the participation of ANS or RAA system in modification of individual HRV frequency bands is not as specific as in humans, we confirmed the participation of RAA system in determination of the VLF band.


2021 ◽  
Vol 5 ◽  
pp. 93
Author(s):  
Jesse Coleman ◽  
Amy Sarah Ginsburg ◽  
William M. Macharia ◽  
Roseline Ochieng ◽  
Guohai Zhou ◽  
...  

Background: Heart rate (HR) and respiratory rate (RR) can be challenging to measure accurately and reliably in neonates. The introduction of innovative, non-invasive measurement technologies suitable for resource-constrained settings is limited by the lack of appropriate clinical thresholds for accuracy comparison studies. Methods: We collected measurements of photoplethysmography-recorded HR and capnography-recorded exhaled carbon dioxide across multiple 60-second epochs (observations) in enrolled neonates admitted to the neonatal care unit at Aga Khan University Hospital in Nairobi, Kenya. Trained study nurses manually recorded HR, and the study team manually counted individual breaths from capnograms. For comparison, HR and RR also were measured using an automated signal detection algorithm. Clinical measurements were analyzed for repeatability. Results: A total of 297 epochs across 35 neonates were recorded. Manual HR showed a bias of -2.4 (-1.8%) and a spread between the 95% limits of agreement (LOA) of 40.3 (29.6%) compared to the algorithm-derived median HR. Manual RR showed a bias of -3.2 (-6.6%) and a spread between the 95% LOA of 17.9 (37.3%) compared to the algorithm-derived median RR, and a bias of -0.5 (1.1%) and a spread between the 95% LOA of 4.4 (9.1%) compared to the algorithm-derived RR count. Manual HR and RR showed repeatability of 0.6 (interquartile range (IQR) 0.5-0.7), and 0.7 (IQR 0.5-0.8), respectively. Conclusions: Appropriate clinical thresholds should be selected a priori when performing accuracy comparisons for HR and RR. Automated measurement technologies typically use median values rather than counts, which significantly impacts accuracy. A wider spread between the LOA, as much as 30%, should be considered to account for the observed physiological nuances and within- and between-neonate variability and different averaging methods. Wider adoption of thresholds by data standards organizations and technology developers and manufacturers will increase the robustness of clinical comparison studies.


Author(s):  
Hugo Farne ◽  
Edward Norris-Cervetto ◽  
James Warbrick-Smith

You should ask the nurse: • What the trend is in urine output—has it been gradually decreasing, or suddenly stopped? If the latter, have they checked if the urinary catheter is blocked by flushing it? This is a rapidly reversible cause of poor urinary output. • What the observations are for the patient. Ask for the heart rate, blood pressure, respiratory rate, oxygen saturations, and temperature, so you can get an idea of how unwell the patient is. This will help you prioritize how soon you need to see the patient. Healthy adults have a urine output of about 1 mL/kg/hour. Oliguria refers to a reduced urine output and is defined variously as <400 mL/day, <0.5 mL/kg/hour, or <30 mL/hour. Anuria refers to the complete absence of urine output. Decreased urine output should be taken very seriously as it may be the first (and only) sign of impending acute renal failure. Untreated, patients may die from hyperkalaemia, profound acidosis, or pulmonary oedema due to the kidneys not performing their usual physiological role. Normal urine output requires: • adequate blood supply to the kidneys • functioning kidneys, and • flow of urine from the kidneys, down the ureters, into the bladder, and out via the urethra. Pathology affecting any of these requirements can result in poor urine output, which is why the differential diagnosis for poor urinary output is often classified as shown in Figure 22.1. In practice, as a junior doctor you want to diagnose and treat the prerenal and postrenal causes. If you come to the conclusion that it is a renal cause (by exclusion), call the renal physicians for an expert opinion. This is crucial in determining the diagnosis: • Adequate intake? Remember that an adult of average size will require about 3 L of fluid intake per 24 hours (30–50 mL/kg/day). Febrile patients will require an extra 500 mL for every 1 °C above 37.0 °C to compensate for increased loss of fluids from evaporation and increased respiratory rate.


1955 ◽  
Vol 33 (3) ◽  
pp. 436-447 ◽  
Author(s):  
H. G. Downie ◽  
J. A. F. Stevenson

Although the blood pressure is one of the important criteria in the standardization of hemorrhagic shock in the dog, it has rarely been used for this purpose in the rat. A method resembling the reservoir technique developed by Wiggers and Werle (1942) for the dog using blood pressure as the criterion has been modified for use with the rat. Male Sprague-Dawley rats weighing approximately 400 gm. were used. In the standardization of this technique the blood pressure was reduced to 30 mm. Hg in a 10-min. period of hemorrhage and then maintained at this level by subsequent small hemorrhages into the reservoir until reinfusion indicated the beginning of vascular collapse, at which time all the blood in the reservoir was returned. Considering that those animals which lived longer than 48 hr. were survivors, in a series of 27 animals, 21 died and 6 survived—a mortality rate of 78%.During the hypotensive period there was a consistent and steady drop in the respiratory rate and rectal temperature. The heart rate declined initially and tended to recover as the hypotensive period progressed. After reinfusion the blood pressure rose but. did not reach prehemorrhage levels. Hemorrhage into the bowel and convulsions were significant postreinfusion findings.


Author(s):  
Matt Wise ◽  
Paul Frost

Critical illness can be considered to be any disease process which causes physiological instability that leads to disability or death within minutes or hours. Fortunately, physiological instability associated with critical illness is easily detected by perturbations of simple clinical observations such as blood pressure, heart rate, respiratory rate, oxygen saturations, level of consciousness, and urine output. Individual abnormalities in these observations are sensitive for the presence of critical illness but non-specific. Specificity for critical illness improves as the number of abnormal clinical observations increases. Over recent years, a greater appreciation of the importance of deviations in simple clinical observations as a method of detecting critical illness has led to the development of a number of ‘early warning’ or ‘track and trigger’ systems. These systems attribute a score according to the magnitude and number of abnormal observations that are present, and a high score prompts immediate medical review. Although intuitively sensible, the evidence that these systems are effective in ameliorating or preventing critical illness is currently lacking. This chapter looks at the approach to diagnosis of critical illness, including the pitfalls in diagnosis.


1989 ◽  
Vol 66 (4) ◽  
pp. 1736-1743 ◽  
Author(s):  
L. B. Rowell ◽  
D. G. Johnson ◽  
P. B. Chase ◽  
K. A. Comess ◽  
D. R. Seals

The experimental objective was to determine whether moderate to severe hypoxemia increases skeletal muscle sympathetic nervous activity (MSNA) in resting humans without increasing venous plasma concentrations of norepinephrine (NE) and epinephrine (E). In nine healthy subjects (20–34 yr), we measured MSNA (peroneal nerve), venous plasma levels of NE and E, arterial blood pressure, heart rate, and end-tidal O2 and CO2 before (control) and during breathing of 1) 12% O2 for 20 min, 2) 10% O2 for 20 min, and 3) 8% O2 for 10 min--in random order. MSNA increased above control in five, six, and all nine subjects during 12, 10, and 8% O2, respectively (P less than 0.01), but only after delays of 12 (12% O2) and 4 min (8 and 10% O2). MSNA (total activity) rose 83 +/- 20, 260 +/- 146, and 298 +/- 109% (SE) above control by the final minute of breathing 12, 10, and 8% O2, respectively. NE did not rise above control at any level of hypoxemia; E rose slightly (P less than 0.05) at one time only with both 10 and 8% O2. Individual changes in MSNA during hypoxemia were unrelated to elevations in heart rate or decrements in blood pressure and end-tidal CO2--neither of which always fell. We conclude that in contrast to some other sympathoexcitatory stimuli such as exercise or cold stress, moderate to severe hypoxemia increases leg MSNA without raising plasma NE in resting humans.


Sign in / Sign up

Export Citation Format

Share Document