A study of metoprolol in fess surgery with respect to monitoring of mean arterial pressure at tertiary health care centre

Gajanan Panjabrao Dhakne¹, Virendra Rajkumar Modi^2*

Abstract               Background: Nasal anatomy and the vascularity of the nose limit ESS. Excessive bleeding not only makes the surgical procedure more difficult but also increases the incidence of complications. Aims and objectives: To Study Metoprolol in FESS surgery with respect to monitoring of mean arterial pressure at tertiary health care centre. Methodology: After the Ethics comitee approval and informed consent, 50 patients, age group 19=8-60 yrs, ASA Grade 1 and 2 for functional endoscopic sinus surgery were included into the study carried out at Government medical college Akola in the Department of Anesthesiology. Group I: Patient receiving oral Metoprolol, Group II: Patient receiving Oral Clonidine, The statistical analysis was doen by SPSS 20 version software. Result: The mean age and weight were compared by t-test. No significant difference is present between groups with regard to the age and weight of patient. The study conducted of two groups; Group I Metoprolol and Group II Clonidine, with 25 patients undergoing Functional endoscopic endoscopic sinus surgeries in both the groups (n=25 in each group).Fisher’s test shows no significant difference in the sex of the two groups. There was no any significant difference in premedication and post induction and post extubation values in both the groups. Mean peri operative mean arterial blood pressure was compared to its basal values in both the groups. There was significant decrease in premedication and post induction values in both metoprolol and clonidine group, while no such difference was found in post extubation values. Conclusion: It can be concluded from our study that, metoprolol and clonidine reduced the MAP as compared to basal values but comparable with each other.

Key Words: FESS (Functional Endoscopic sinus surgery), Metoprolol, clonidine, MAP (Mean Arterial Pressure).

INTRODUCTION

Endoscopic sinus surgery (ESS) is well established in the treatment of a variety of sinonasal diseases. Rigid endoscopy allows superior visualization and permits accurate diagnosis of disease that can be missed by anterior rhinoscopy.¹ Nevertheless, both nasal anatomy and the vascularity of the nose limit ESS. Excessive bleeding not only makes the surgical procedure more difficult but also increases the incidence of complications. Early series have reported major complications in 1% to 2% of patients. These include intraorbital hemorrhage, optic nerve damage, ocular muscle injury, dural injury with intracranial penetration, cerebrospinal fluid leak with possible meningitis, and intracranial hemorrhage.^2–5

MATERIAL AND METHODS

After the Ethics comitee approval and informed consent, 50 patients, age group 19=8-60 yrs, ASA Grade 1 and 2 for functional endoscopic sinus surgery were included into the study carried out at Government medical college Akola in the Department of Anesthesiology. A Randomized prospective double blind study with 2 groups (25 patients in each group) was conducted: Group I: Patient receiving oral Metoprolol, Group II: Patient receiving Oral Clonidine. The patients with age between 18-60 yrs., ASA Grade 1 and 2, were included into the study while, patient who doesn’t given consent, ASA Grade 3and 4, hypertensive patients/other ECG changes Asthmatics, Baseline pulse <55/systoloic BP <100 mm Hg, H/o Bleeding disorder were excluded from the study. The blood pressure record like mean blood pressure record was calculated by Systolic and diastolic blood pressure. The statistical analysis was doen by SPSS 20 version software.

RESULT

Table 1: Age and Weight distribution between groups

The mean age and weight were compared by t-test. No significant difference is present between groups with regard to the age and weight of patient.

Table 2: Sex distribution between Groups

The study conducted of two groups; Group I Metoprolol and Group II Clonidine, with 25 patients undergoing Functional endoscopic endoscopic sinus surgeries in both the groups (n=25 in each group).Fisher’s test shows no significant difference in the sex of the two groups.

Table 3: Distribution of the patients as per the Mean Arterial Blood Pressure in the peri-operative period

Figure 1: Showing patients as per the Mean Arterial Blood Pressure in the peri-operative period

Table 4: MAP Comparison with basal (Study drug administration) value

Mean peri operative mean arterial blood pressure was compared to its basal values in both the groups. There was significant decrease in premedication and post induction values in both metoprolol and clonidine group, while no such difference was found in post extubation values.

DISCUSSION

The lowering of MAP during general anesthesia can minimize intraoperative bleeding.^6,7,8 However, controlled MAP hypotension to values ranging from 50 to 60 mm Hg has been associated with ischemic organ failure.⁹ In ESS, such measures are uncommon and controversial because the aim is not to minimize blood transfusion but to improve intraoperative endoscopic visibility. Regarding hemodynamic variables, not only MAP but also venous pressure and capillary blood flow account for the extent of surgical bleeding. Of these variables, only arterial pressure is easily and readily measured; hence, the correlation between MAP and blood loss is studied. It has been postulated that reduction of MAP during general anesthesia (GA) can minimize intraoperative bleeding.^10,11 But regarding hemodynamic variables, not only MAP, but also venous pressure and capillary blood flow account for the extent of surgical bleeding. Of these variables, only arterial pressure is easily and readily measured. However studies ¹² have demonstrated that MAP and total blood loss are not necessarily correlated. Improved surgical field during FESS with a beta blocker has been attributed to vasoconstriction of the mucous membrane arterioles and pre-capillary sphincters resulting from unopposed alpha adrenergic effects of endogenous catecholamines¹³ and solely on the effect of MAP. In the study by Nair et al. ¹² they found a correlation with HR and surgical field grade as there was a better surgical field with a reduction in HR. The metoprolol group had a significantly lower HR than the placebo group. The mean age and weight were compared by t-test. No significant difference is present between groups with regard to the age and weight of patient. The study conducted of two groups; Group I Metoprolol and Group II Clonidine, with 25 patients undergoing Functional endoscopic endoscopic sinus surgeries in both the groups (n=25 in each group).Fisher’s test shows no significant difference in the sex of the two groups. Mean peri operative, mean arterial blood pressure compared to its basal values in both the groups there was no any significant difference in premedication and post induction and post extubation values Mean peri operative mean arterial blood pressure was compared to its basal values in both the groups. There was significant decrease in premedication and post induction values in both metoprolol and clonidine group, while no such difference was found in post extubation values

CONCLUSION

It can be concluded from our study that, metoprolol and clonidine reduced the MAP as compared to basal values but comparable with each other.

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