Abstract The thyroid gland act for increase its secretion lead to high level of hormone in serum, acceleration metabolic activity in the body. Through the dental clinic evaluation of systemic disease medical history or hyperthyroidism before treatment. The local anesthesia in dental clinic used Mepivacaine Hydrochloride 3% due to the adrenaline is contra indicated and felypressin do not safe. The objective of study to examine the safety of plain anesthesia in dental clinic for hyperthyroidism patients on blood pressure, the heart rate and pulmonary function after taken local anesthesia. Study done for (51) hyperthyroidism female patients which divided in to two groups depend on age young, group I (20-29) years and group II (30-39) years. Then can be exam blood pressure, heart rate, lung function test and O₂ transport before given the local anesthesia (plain anesthesia) and repeated the same parameter after given the local anesthesia. the heart rate systolic pressure for hyperthyroidism patients higher than normal while the diastolic pressure within normal value and there is a statistically no significant change P ≥ 0.05 for the parameters (systolic pressure, diastolic pressure, heart rate, O₂ transport and lung function test FVC(forced vital capacity), FEV1(forced expiratory volume), FEV1/FVC). The study improve the plain local anesthesia (Mepivacaine Hydrochloride 3%) for the hyperthyroidism patients the systolic blood pressure, diastolic blood pressure, the heart rate and the pulmonary function, do not effected after taking anesthesia that lead the dental treatment can done without complication.

Keywords: Plain anesthesia, Hyperthyroidism patient, Systolic pressure, Diastolic pressure, Pulmonary function test

Citation: Al-Yasiry, A.M., Abed–Alhussian Alyassery, A.M., Al-Jammali, Z.M., and Alsaadi, M.A. 2026. Physiological responses to plain local anesthesia in hyperthyroid patients: assessment of blood pressure, heart rate, and respiratory volume in a dental clinic. Natural and Life Sciences Communications. 25(2): e2026026.

Graphical Abstract:

INTRODUCTION

High thyroid gland secretion's lead to high level of hormone in serum and acceleration metabolic activity in the body. This state caused hyperthyroidism disease (Ganesan et al., 2021). The cause of hyperthyroidism vary depended on incidence report different factors like ethical origin, the structure population and iodine dietary taken. The main common cause of hyperthyroidism is dysfunction of the hormone with mild, moderate iodine insufficiency in the areas (Taylor et al., 2018). The disease occur in the ages between (20-50) years, it prevalence highly for Graves’ disease ’secondary’; after the old ages (50 years) the toxic goiter” multinodular” may be occur, but the young ages may be effected with toxic adenoma. All type of disease mostly occur in women (Ganesan et al., 2021). The hyperthyroidism disease almost occur in the women about 2% while the men effected about 0.2% may be hormonal reason like; Graves’ disease, goiter (toxic multinodular), adenoma (solitary toxic) and other this disease related to increased release of thyroid hormone (van der Spek et al., 2017; Talib and Taha, 2024). The cardiovascular system, the gastro-intestinal system, the hepatic system and the nervous system are affected with hyperthyroidism. The thyroid hormone and liver play important role for maintaining the homeostatic state in those site. The glucuronidated and sulfated are form from thyroid hormone that which excreted through the bile (van der Spek et al., 2017). The affection of the disease that caused the patients suffered from loss body weight (hyper-metabolism), inability withstand heat, instability emotion, increase appetite (hyper-metabolism), tremor, diaphoresis, also arise the cardiac out-put sinus tachycardia, ionotropic and chronotropic markedly, hypertension and murmur of systolic heart (Al-Yasiry and Al-Jammali, 2020). Un-treated hyperthyroidism with long standing may be progressive to atrial fibrillation or progress to heart failure (Ivkovic and Puckett, 2016). Weakness of the proximal muscle (neuro-muscular symptom), anxiety to frank psychosis (psychiatric symptom), lid lag, and the looking fixed “retraction of eyelids” hyper-defecation (Ali and Taha, 2024). The symptoms can be explain physiology due to increased thyroid hormone level in serum magnify catecholamine signal by arise the number of beta-adrenergic receptors in cell (Delgado-González et al., 2016; Xayavong et al., 2025). The adrenergic stimulation give the sign and symptom for the patients such as anxiety and tachycardia which occur more in the young patients (Pingitore et al., 2023). Other effect of the hormone for tissue, organ and systems, it act arise the thermogenesis of the tissue, basal metabolism rate and diminished cholesterol level in serum and vascular resistance systemically (An et al., 2023). Some hyperthyroidism patients specifically euthyroid suspected to develop asthma. The asthma result from increasing (super-oxide production, produce prostaglandin which is “broncho-constrictive” produce catecholamine sensation) (Kumar et al., 2022).

Through the dental clinic evaluation of systemic disease medical history or hyperthyroidism was done before treatment (Geduk and Haylaz, 2021). Examination of oral cavity for hyperthyroidism patients which is showing increased suspecting to dental caries and periodontal disease, osteoporosis in “maxillary and mandibular” enlargement occur in extra-glandular thyroid tissue (lateral posterior tongue), and may be the teeth eruption accelerated (Al-Yasiry and Al-Jammali, 2020). The drug used in dental clinic interaction with hyperthyroidism, care must be taken before treatment (Mahajan and Kapoor, 2022). So that the local anesthesia in dental clinic with adrenaline is contra indicated and felypressin do not safe (Oliver et al., 2016). The composition of local anesthesia consist of salts and vaso-conscrictor drug (epinephrine, phenylephrine, noradrenaline, felypressin) acted directly on vascular system (blood vessel) to anesthesis the area by vaso-consrtiction of the blood vessel one side and occur side effect on the blood pressure and heart rate, the affection can explain of adrenaline prompting exciting movement for myocardium, palpitation and tachycardia that bring about increase the heart rate systolic blood pressure, other hand  phenylephrine and noradrenaline in local anesthesia outcome arise systolic, diastolic blood pressure in dental clinic (Al-Yasiry et al., 2020). Those reason cautious must be gotten during given local anesthesia or other drug through treatment (Duntas and Jonklaas, 2019), so this study was to examine the safety of plain anesthesia in dental clinic for hyperthyroidism patients on blood pressure, the heart rate and pulmonary function after taken local anesthesia.

Pulmonary function testing was included because thyroid hormones influence respiratory muscle strength and metabolic rate. Evaluating lung function ensures that local anesthesia does not adversely affect respiratory performance, which is particularly relevant in hyperthyroid patients who may experience dyspnea or increased oxygen demand (Duntas and Jonklaas, 2019).

MATERIALS AND METHODS

This study was done at the Babylon University, Faculty of Dentistry, conservative department and surgery department for eight month “October to June/2024”. Ethical approval was obtained from the Ethical Review Committee, College of Dentistry, University of Babylon (Approval No. 5500, dated 15 January 2024). Written informed consent was obtained from all participants before inclusion, in accordance with the Declaration of Helsinki.

Sample

This study conceded out participate female patient with young age (20-37) years that taken medication for hyperthyroidism and need to fill or extract their teeth, with exclusion any other systemic disease. The acquiescence from was getting from the individual after explaining the procedure of study as well as the probability of dis-comfortability or risk. The number of the patients were (51) divided into groups depend on ages as shown in the figure 1, were can be examined the blood pressure, heart rate, oxygen transport and pulmonary function test before given the anesthesia and repeated after (5-10) minute after given the anesthesia. The blood pressure (systolic and diastolic in mmHg) and heart rate are measured aid by a digital tension-meter (clinically validated measurement accuracy 2004, German Hypertension Society), oxygen transport measured by oximeter (Jumper, pulse Oximeter, Med Path Gmbh Mies-van-Rohe-Strasse8. 80807 Munich, Germany), and the pulmonary function test before given anesthesia can exam to same patients using spirometer (type Spirobank II^®; Italy, MIR, Rome) (Figure 2). After fill all information related to spirometer such as (weight, height without shoes, name, age, ethnic, medical history) put the nasal clip on the nose to ensure all the breathing by the mouth and given the mouth piece to the patient learn to bit by the teeth on the mouth piece with close fit of the lip on it and ask him get deep breath through the mouth piece and expel strongly expiration (Al-Saadi et al., 2019). Through appointment those parameter repeated more than two time at "relax state" after given the local anesthesia "plain anesthesia" (contain Mepivacaine Hydrochloride 3% only one cartridge) recurrence the exam (same parameter) after [5-10] minute.

Figure 1. The design of study and classified distribution of sample.

Figure 2. A: The device for measured blood pressure “Beurer”, B: Image for local anesthesia “Mepivacaine Hydrochloride 3%”, C: The device for measurement of Oxygen “Oximeter”, D: Image for spirometer result.                      

Statistical analysis

The data were evaluated and tested using IBM SPSS software 22 and expressed as mean ± standard deviation and the following statistical tests were applied: Analysis of Variance for Repeated Measures Tukey-Kramer Multiple Comparisons, with level of significance of 5% and the significant level of differences set at P < 0.05.

Ethical approval 

The study was conducted in accordance with the ethical guidelines found in the Helsinki Declaration. Before a sample was taken, it was done with the patient's verbal and analytical consent. A local ethics committee examined and approved the study protocol, subject information, and consent form in accordance with document number 5500 (in 15/1/2024) to obtain this approval.

RESULTS

Through the existing study, there is no significant different for systolic pressure, diastolic pressure and heart rate (P ≥ 0.05) in hyperthyroidism female patients during dental clinic pre-given anesthesia and post-given anesthesia in Table (1, 3) for both age. As well as there is no significant different for the pulmonary function test (FVC, FEV1, FEV1/FVC) and O₂ transport before taken anesthesia and after that for both female ages in Table (2, 4). 

Table 1. The mean ± standard deviation (SD) between the systolic, diastolic pressure and heart rate for the hyperthyroidism patients group I before and after given injection.

Table 2. The mean ± standard deviation (SD) between FVC, FVE1, FEV1/FVC and O2transport for the hyperthyroidism patients group I before and after given injection.

Note: FEV1 (forced expiratory volume in first second)

Table 3. The mean ± standard deviation (SD) between the systolic, diastolic pressure and heart rate (HR) for group II years before and after given injection.

Table 4. The mean ± standard deviation (SD) between FVC, FVE1, FEV1/FVC and O2transport for the hyperthyroidism patients group II years before and after given injection.

DISCUSSION

The hyperthyroidism disease caused by increase in the blood stream by "T3, T4" hormone (Qasim Ali et al., 2017). The thyroid hormone have the same action of sympathetic nerve, which increased the heart rate "tachycardia" (Ciulla et al., 2015), so the T3, T4 caused excess of metabolism activity with of cardiovascular system exhibition such as arise blood pressure "systolic", heart rate but “diastolic pressure don’t effected by the thyroid hormone stay normal”, that caused "supra-ventricular arrhythmias" (Irigaray et al., 2024), and other effect elevated the hyper-sensitivity to neurotransmitter action for those patients (Navarro-Navajas et al., 2022). Also clinically the hyperthyroidism patients suffer from increased "heart rate, cardiac out-put" but decreased "systemic vascular-resistance", and hyper-dynamic cardio-vascular state, dyspnea, intolerant the exercise (Navarro-Navajas et al., 2022).

In dental clinic, it associated local anesthesia  used Mepivacaine Hydrochloride to reduce complication during treatment (Akers, 2019) that given due to the vasoconstrictor "adrenaline" mostly for prolong the time of anesthesia, appropriate hemostasis (Deol et al., 2023), but the used adrenaline act as sympathomimetic substance with  adrenergic effect in endocrinopathy  such hyperthyroidism diseases (Costa et al., 2024), the vasoconstrictor solution present in anesthesia like, epinephrine, phenylephrine noradrenaline and fely-pressin, with anesthesia salt, that have direct effect for blood vessel in injected area "systemically" lead to vaso-constricted, amplified heart rate, systolic pressure, these achieved through the dental clinic (Al-Yasiry et al., 2020). So that the hyperthyroidism patients avoid give anesthesia with adrenaline due to that causes increase with blood pressure (Verma and Dwivedi, 2022), Mackey DC mentioned the usage of injection with adrenaline caused highly awareness to the patients (Mackey, 2024). That reason made care in dental clinic contraindication used "adrenaline or any other vaso-pressor agents" (Malamed, 2019; Qasim Ali et al., 2017).

This study refer the systolic blood pressure higher than normal by effect of thyroid hormone, the result pre-injection and post-injection slightly differ may be due to the patient anxiety, it’s fearing from anything caused stress (Al-Jammali et al., 2024; Z.M. Al-Jammali et al., 2024), no significant differences observed among this patients P ≥ 0.05 this may be related to the plain anesthesia contain Mepivacaine Hydrochloride 3% (without adrenaline)  and there is no differences between these two ages (Kulandayan and Sivanadiyan, 2024).

 The diastolic blood pressure within normal value in hyperthyroidism patients so the thyroid hormone have no action on diastolic blood pressure (Razvi et al., 2018) and patients pre-injection and post-injection are within the normal value there no significant change and this may be due to the composition of plain anesthesia [Mepivacaine Hydrochloride 3%] for both ages. The heart rate increased with disease (sympathetic activity of thyroid hormone), the result of pre-injection and post-injection don’t give significant difference but there is slightly difference may be related the stress from the dental clinical and the plain anesthesia don’t acted on the heart to increase or decrease activity of the heart (Stevens et al., 2021).

The spirometer exam give the normal result (FVC, FV1, FVC/FV1, O₂ transport) and there is no significant change for this date the caused due to the plain anesthesia don’t influence on the respiratory system disease (Lie et al., 2020). Also there is no significant change in (FVC, FEV1, FEV1/FVC and O₂ transport) for both ages in pre-injection and post-injection depended on safety of plain anesthesia. The hyperthyroidism patients almost with raised (cardiac output, heart rate) (Arslan and Altay, 2021) and suffered from dyspnea and intolerance the exercise sympathetic stimulation (Navarro-Navajas et al., 2022). In general there’s no thesis related to plain anesthesia to improve the result or agree, disagree with this study.

Limitation 

The limitation of the study the number of the case limited due to determination within ages and excluded other systemic disease the study can be broaden by included the older ages and the young and old age male.

CONCLUSION

The study shown that the safety of local anesthesia without adrenaline “plain anesthesia” for the hyperthyroidism patients for the systolic blood pressure, diastolic blood pressure heart rate and the pulmonary function and there is no increased blood pressure or tachycardia or dyspnea during dental treatment, patients treated without complication.

ACKNOWLEDGEMENTS

The authors thank the College of Dentistry, University of Babylon for providing instruments.

AUTHOR CONTRIBUTIONS

Anas Moez Al-Yasiry: Conceptualization (Lead), Study Design (Lead), Clinical Assessment (Lead), Writing – Original Draft (Lead); Aoss Moez Abed-Alhussian Alyassery: Data Collection (Equal), Patient Management (Equal); Zainab Mahmood Al-Jammali: Data Analysis (Lead), Data Interpretation (Equal), Writing – Review & Editing (Equal); Malath Azeez Alsaadi: Literature Review (Equal), Writing – Review & Editing (Equal).

CONFLICT OF INTEREST

The authors declare that they hold no competing interests.

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