Chronic rhinosinusitis (CRS) is a widespread condition that significantly impacts the global population, with estimates indicating that it affects around 5-15% of individuals worldwide. This chronic inflammatory disease of the sinonasal cavities leads to persistent symptoms such as nasal obstruction, facial pain, and reduced sense of smell, often impairing quality of life. In India, the burden of CRS is exacerbated by environmental factors such as high pollution levels, dust, and allergens, which increase the prevalence of respiratory diseases. The socio-economic impact of CRS in India is considerable, resulting in both direct healthcare costs and indirect costs such as lost productivity. Functional Endoscopic Sinus Surgery has emerged as the gold standard treatment for chronic rhinosinusitis that does not respond to medical management, offering a minimally invasive approach to address the anatomical causes of the disease. However, the high incidence of sinonasal diseases in India necessitates improved surgical techniques to optimize outcomes and ensure the best possible recovery for patients (1). Functional Endoscopic Sinus Surgery allows for direct visualization of the sinuses through endoscopic means, enabling surgeons to remove obstructive tissue and restore sinus drainage. Despite its advantages, one of the key challenges in Functional Endoscopic Sinus Surgery is managing intraoperative bleeding, which can obstruct the view of the surgical site and make it difficult to navigate critical anatomical structures. Blood loss during surgery can also increase the risk of complications and adversely affect postoperative recovery. To overcome this, controlled hypotension is often employed to reduce vascular flow to the surgical site, thereby improving visualization. Pharmacological interventions such as volatile anesthetics, vasodilators, and beta-blockers are commonly used to induce controlled hypotension and minimize bleeding. Among these, oral clonidine and oral metoprolol have been specifically investigated for their ability to achieve controlled hypotension in otorhinolaryngological surgeries like Functional Endoscopic Sinus Surgery (2, 3). Clonidine, a centrally acting alpha-2 agonist, and metoprolol, a selective beta-1 adrenergic blocker, have both shown promise in reducing mean arterial pressure (MAP) and surgical field bleeding, making them potential premedication options for patients undergoing Functional Endoscopic Sinus Surgery (4,5). Despite the established efficacy of clonidine and metoprolol in inducing controlled hypotension, there remains a gap in the literature regarding a direct comparison of their effectiveness specifically in the context of Functional Endoscopic Sinus Surgery. While both drugs have been found to improve surgical conditions and reduce blood loss, the results from existing studies have been inconsistent, with some showing greater benefits with clonidine, while others support the use of metoprolol (5,6). Furthermore, the potential side effects and limitations associated with each agent—such as clonidine's sedative effects and metoprolol's impact on heart rate—require careful consideration, especially in a patient population with varying co-morbidities. The need for additional research is therefore paramount, as a well-designed study comparing these two agents could provide clearer guidance on their respective roles in improving surgical field quality, enhancing hemodynamic stability, and ensuring patient safety during Functional Endoscopic Sinus Surgery (6). This research could lead to more personalized and effective treatment protocols, ultimately improving the surgical outcomes for patients worldwide and in the Indian context.

Study Design This is a hospital based, cross sectional study. Sample Size The study involves a total population of 100 patients undergoing Functional Endoscopic Sinus Surgery, divided into two groups of 50 each. The sample size was calculated using data from Keshari et al. (8), with a mean blood loss of 100.0 ml for the clonidine group and 125.6 ml for the metoprolol group, and a pooled standard deviation of 25.9 ml. The effect size was determined, and with a significance level of 0.05 and 80% power, 50 patients per group were required to ensure reliable results. Inclusion Criteria • Patients of 18 to 60 years of age • Patients belonging to ASA grading I and II • Patients undergoing only Functional Endoscopic Sinus Surgery • No history of allergy to the drugs. Exclusion Criteria • Patient’s refusal or non-cooperative patients • Patients with heart diseases or Bradycardia (HR<60/min) • Patients with uncontrolled hypertension • Patients with bleeding disorders Methodology Patients scheduled for surgery were evaluated a day prior, with necessary investigations conducted, and informed consent for participation was obtained. A total of 100 patients undergoing Functional Endoscopic Sinus Surgery were enrolled and randomly assigned to two groups of 50 each. Group A received 200 mcg of oral clonidine as pre-medication two hours before surgery, while Group B received 50 mg of oral metoprolol at the same time. Prior to induction, baseline heart rate and blood pressure were recorded using a 3-lead ECG and a non-invasive blood pressure monitor. After three minutes of preoxygenation with 100% oxygen, general anesthesia was induced with intravenous fentanyl (2 mcg/kg), propofol (2 mg/kg), and atracurium (0.5 mg/kg). The airway was secured with an appropriately sized endotracheal tube. Anaesthesia maintenance was achieved with sevoflurane and atracurium. Heart rate and blood pressure were monitored at five-minute intervals for the first 15 minutes after intubation, then every 15 minutes for up to two hours or until the end of the surgery. Blood loss was assessed at the conclusion of the procedure by measuring the blood collected in the suction bottle. Statistical Analysis Data entry was performed in M.S. Excel and analyzed using Statistical Package for Social Sciences (SPSS Version 16) for Windows. Descriptive statistics summarized categorical variables as frequencies (n, %) and quantitative variables as mean ± S.D. Results were presented in tables and visualized using bar or pie charts. The t-test was used for comparing two groups, and the chi-square test for categorical variables. Statistical significance was defined as a P-value < 0.05. Ethical Approval Institutional Ethical Approval received prior to commencement of study.

Table 1: ASA Classification Distribution in Clonidine and Metoprolol Group Group Total Clonidine Metoprolol ASA GROUP 1 n 28 23 51 % 56.0% 46.0% 51.0% 2 n 22 27 49 % 44.0% 54.0% 49.0% Total n 50 50 100 % 100.0% 100.0% 100.0% Chi-square: 1.00, P Value: 0.21, Statistically not significant In the clonidine group, 28 patients (56%) belonged to ASA class 1, and 22 patients (44%) belonged to ASA class 2. In contrast, the metoprolol group had 23 patients (46%) in ASA class 1 and 27 patients (54%) in ASA class 2. A Chi-square analysis yielded a value of 1.00 with a P-value of 0.21, indicating that there was no statistically significant difference in the distribution of ASA classifications between the two groups. Table 2: Comparison of Heart Rate (HR) Between Clonidine and Metoprolol Groups During Surgery Clonidine Metoprolol T Test P Value Mean SD Mean SD HR Before Induction 74.24 9.673 73.80 8.497 0.24 0.81 5 Min 68.72 6.068 81.84 4.958 -11.83 0.001 15 Min 72.40 5.810 80.76 6.036 -7.05 0.001 30 Min 67.86 4.845 82.74 4.110 -16.56 0.001 45 Min 64.12 3.324 75.24 3.236 -16.95 0.001 60 Min 65.02 3.165 73.54 2.984 -13.84 0.001 75 Min 65.90 5.152 71.32 3.582 -6.10 0.001 90 Min 65.62 4.179 75.14 6.704 -8.52 0.001 Before induction, the mean heart rate was comparable between the clonidine group (74.24 ± 9.67 beats/min) and the metoprolol group (73.80 ± 8.50 beats/min), showing no statistically significant difference (P=0.81). However, at all measured intervals during surgery (from 5 minutes to 90 minutes), the clonidine group consistently exhibited significantly lower heart rates compared to the metoprolol group (P=0.001 at each interval). The greatest difference occurred at 30 and 45 minutes, suggesting that clonidine was more effective in controlling heart rate and maintaining hemodynamic stability during the procedure. Table 3: Comparison of Systolic Blood Pressure (SBP) Between Clonidine and Metoprolol Groups During Surgery Clonidine Metoprolol T Test P Value Mean SD Mean SD SBP Before Induction 118.38 10.386 119.14 11.732 -0.34 0.73 5 Min 108.68 7.860 111.26 7.417 -1.68 0.09 15 Min 102.12 7.927 110.08 6.442 -5.51 0.001 30 Min 93.38 3.109 104.60 3.030 -18.27 0.001 45 Min 93.24 4.383 104.98 2.646 -16.21 0.001 60 Min 88.76 3.456 101.80 4.558 -16.12 0.001 75 Min 90.10 3.086 99.04 5.703 -9.74 0.001 90 Min 93.18 4.332 99.96 3.398 -8.70 0.001 Before induction, the systolic blood pressure (SBP) was comparable between the clonidine (118.38 ± 10.39 mmHg) and metoprolol groups (119.14 ± 11.73 mmHg), with no statistically significant difference (P = 0.73). At 5 minutes, the difference between groups remained statistically insignificant (P = 0.09). However, from 15 minutes onwards until 90 minutes, the clonidine group exhibited significantly lower SBP values compared to the metoprolol group (P = 0.001 at all intervals). The most substantial difference was noted at 30 minutes, indicating that clonidine is notably more effective than metoprolol in achieving controlled hypotensive anesthesia and maintaining hemodynamic stability during surgery. Table 4: Comparison of Diastolic Blood Pressure (DBP) Between Clonidine and Metoprolol Groups During Surgery Clonidine Metoprolol T Test P Value Mean SD Mean SD DBP Before Induction 79.90 6.717 84.10 8.577 -2.72 0.008 5 Min 78.58 6.250 85.66 3.179 -7.13 0.001 15 Min 68.10 4.460 85.02 3.047 -22.15 0.001 30 Min 64.60 3.423 80.08 3.516 -22.30 0.001 45 Min 67.96 4.338 75.44 3.189 -9.82 0.001 60 Min 67.98 4.433 72.70 2.558 -6.52 0.001 75 Min 67.90 4.181 78.12 5.236 -10.78 0.001 90 Min 67.40 4.772 75.16 4.022 -8.79 0.001 Before induction, the mean diastolic blood pressure (DBP) was significantly lower in the clonidine group (79.90 ± 6.72 mmHg) compared to the metoprolol group (84.10 ± 8.58 mmHg; P = 0.008). From 5 minutes onward, and continuing throughout the surgery (up to 90 minutes), the clonidine group consistently maintained significantly lower DBP levels than the metoprolol group (P = 0.001 at all intervals). The greatest difference was observed at 30 minutes, reinforcing that clonidine was more effective than metoprolol in controlling diastolic blood pressure and maintaining hemodynamic stability during surgery. Table 5: Comparison of Mean Arterial Pressure (MAP) Between Clonidine and Metoprolol Groups During Surgery Clonidine Metoprolol T Test P Value Mean SD Mean SD MAP Before Induction 92.68 5.974 95.82 6.546 -2.50 0.01 5 Min 88.64 5.042 94.18 3.391 -6.44 0.001 15 Min 79.38 3.864 93.38 2.267 -22.09 0.001 30 Min 74.18 2.447 88.32 2.591 -28.05 0.001 45 Min 76.44 3.233 85.22 2.093 -16.11 0.001 60 Min 74.90 3.131 82.34 2.153 -13.84 0.001 75 Min 75.28 3.031 85.16 3.513 -15.05 0.001 90 Min 76.04 3.319 83.38 2.962 -11.66 0.001 Before induction, the mean arterial pressure (MAP) was significantly lower in the clonidine group (92.68 ± 5.97 mmHg) compared to the metoprolol group (95.82 ± 6.55 mmHg; P = 0.01). At all intraoperative time intervals measured (from 5 to 90 minutes), MAP remained consistently and significantly lower in patients receiving clonidine (P = 0.001 at each interval). The maximum difference between the groups was evident at 30 minutes. These findings clearly suggest that clonidine provided better hemodynamic control and was more effective in achieving hypotensive anesthesia during Functional Endoscopic Sinus Surgery compared to metoprolol. Table 6: Comparison of Oxygen Saturation (SpO₂) Between Clonidine and Metoprolol Groups During Surgery Clonidine Metoprolol T Test P Value Mean SD Mean SD SPO2 Before Induction 98.96 0.807 98.78 0.815 1.10 0.27 5 Min 100.00 0.001 100.00 0.001 - - 15 Min 100.00 0.001 100.00 0.001 - - 30 Min 100.00 0.001 100.00 0.001 - - 45 Min 100.00 0.001 100.00 0.001 - - 60 Min 100.00 0.001 100.00 0.001 - - 75 Min 100.00 0.001 100.00 0.001 - - 90 Min 100.00 0.001 100.00 0.001 - - Before induction, the mean oxygen saturation (SpO₂) was comparable in the clonidine group (98.96 ± 0.81%) and the metoprolol group (98.78 ± 0.82%), with no statistically significant difference (P = 0.27). Throughout the surgical procedure, from 5 minutes to 90 minutes, both groups maintained stable SpO₂ values at 100%, with negligible variation (SD=0.001). This indicates that both clonidine and metoprolol provided excellent and comparable oxygenation levels during surgery. Table 7: Comparison of Intraoperative Blood Loss Between Clonidine and Metoprolol Groups Clonidine Metoprolol T Test P Value Mean SD Mean SD BLOOD LOSS AT THE END OF SURGERY (ML) 39.24 5.850 69.14 20.795 -9.78 0.001 The mean blood loss measured at the end of surgery was significantly lower in the clonidine group (39.24 ± 5.85 ml) compared to the metoprolol group (69.14 ± 20.80 ml). Statistical analysis showed a highly significant difference between the two groups (T-value = -9.78, P = 0.001). These findings clearly demonstrate that clonidine, as pre-medication, is superior to metoprolol in reducing intraoperative blood loss during Functional Endoscopic Sinus Surgery.

The present study aimed to compare the efficacy of clonidine and metoprolol in achieving controlled hypotension during Functional Endoscopic Sinus Surgery, a procedure that requires a bloodless surgical field for optimal visibility and successful outcomes. The results showed that clonidine was superior in controlling blood pressure, heart rate, and blood loss when compared to metoprolol. Specifically, clonidine provided more consistent and significant reductions in systolic and diastolic blood pressure (SBP and DBP) as well as mean arterial pressure (MAP), particularly from 15 to 90 minutes after induction. These findings align with studies by Gohil et al. [12], Keshari et al. [8], and Devendran et al. [9], who also demonstrated that clonidine led to a more pronounced and sustained hypotensive effect. In terms of blood loss, clonidine resulted in significantly lower blood loss (39.24 ml) compared to metoprolol (69.14 ml, P = 0.001), which contributed to better surgical field visibility and improved surgical outcomes. Gohil et al. [12] and Jiwanmall et al. [11] have similarly noted that clonidine’s superior control of blood pressure correlated directly with reduced blood loss and enhanced surgical field quality, a crucial factor in achieving better surgical precision. Heart rate control was another area where clonidine outperformed metoprolol. In the present study, heart rate was significantly lower in the clonidine group at various intraoperative time points, particularly from 5 to 90 minutes post-induction. This finding was supported by studies like those of Gohil et al. [12] and Keshari et al. [8], who reported a greater reduction in heart rate with clonidine compared to metoprolol. However, studies such as Dhakne et al. [10] and Naithani et al. [7] found metoprolol to be more effective at controlling heart rate at certain intervals, suggesting that individual responses to these agents may vary. Despite this variability, the general consensus across studies indicates that clonidine provides more consistent heart rate control throughout the surgical procedure. Interestingly, while both clonidine and metoprolol were found to maintain stable oxygen saturation (SpO₂) levels during surgery, suggesting no detrimental effects on oxygenation, the enhanced blood pressure and heart rate control observed with clonidine played a crucial role in improving the surgical field and minimizing blood loss. This highlights the potential of clonidine as a more effective agent for achieving optimal surgical conditions during Functional Endoscopic Sinus Surgery. The study also evaluated preoperative factors, such as age, gender, weight, and ASA classification, and found no significant differences between the clonidine and metoprolol groups. The mean age in the clonidine group was 38.12 years, and in the metoprolol group, it was 40.34 years, with no statistically significant difference (P = 0.33), in agreement with previous studies like Gohil et al. [12] and Keshari et al. [8]. Similarly, gender distribution was balanced between the two groups, with no significant differences in weight or ASA classification. This indicates that the differences in surgical outcomes were not confounded by these demographic factors. Both groups were comparable in terms of preoperative health status, which further strengthens the validity of the observed differences in hemodynamic control and surgical outcomes. The ASA classification revealed that most patients in both groups were classified as ASA I or II, suggesting that the patient populations were relatively healthy and similar in terms of baseline health status. This further emphasizes that clonidine’s superiority in blood pressure control and blood loss reduction was likely due to the pharmacological properties of the drug rather than patient-specific factors. In conclusion, while both clonidine and metoprolol were effective in achieving controlled hypotension during Functional Endoscopic Sinus Surgery, clonidine emerged as the more reliable choice for improving surgical field visibility, reducing blood loss, and maintaining hemodynamic stability, making it a preferred option for this type of surgery.

The present study concludes that oral clonidine, when used as premedication, is significantly more effective than oral metoprolol in achieving controlled hypotensive anesthesia and ensuring hemodynamic stability during Functional Endoscopic Sinus Surgery. Clonidine provided superior control over intraoperative heart rate, systolic, diastolic, and mean arterial blood pressures resulting in significantly reduced blood loss and enhanced surgical conditions. Both medications were comparable in maintaining oxygen saturation, indicating no compromise in respiratory safety. Thus, oral clonidine is recommended as a preferable premedication agent for hypotensive anesthesia in patients undergoing Functional Endoscopic Sinus Surgery.

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