Comparison of intracuff air, lignocaine, lignocaine with sodium bicarbonate and ketamine for attenuating post operative sore throat

 

Rashmi N R^*, Shashidhar G S^**, Balabhaskar S^***, Kiranchand N^****

 

Abstract               Background and Aims: Tracheal intubation is a foremost cause of trauma to the airway mucosa, resulting in postoperative sore throat (POST) with reported incidence of 21 – 65%.Various pharmacological methods have been used for attenuating POST like topical lignocaine, inflation of endotracheal tube (ETT) cuff with lignocaine, lignocaine with sodium bicarbonate and preoperative ketamine gargle etc. We conducted a study to compare the incidence and severity of POST when intracuff ketamine is used and compared with intracuff air, lignocaine and lignocaine with sodium bicarbonate. Materials and Methods: A randomised study with 100 patients divided into 4 groups of 25 each was done. After intubation, the endotracheal tube cuff was inflated with either air (Group A), 2% lignocaine with normal saline (Group L), 2% lignocaine with 7.5% sodium bicarbonate (Group B) or ketamine with normal saline (Group K) and study parameters like Sore throat with incidence/severity (Mild, Moderate, Severe) and hemodynamics at extubation, TUBE tolerance, hoarseness, dysphagia, postoperative nausea vomiting and cough were observed. The results were tabulated and compared statistically. Results: The incidence and severity of POST was reduced in all groups compared to group A. Tube tolerance was better in Group K, but with slight increase in arterial blood pressure at extubation. Inflation of endotracheal tube cuff with lignocaine, lignocaine with sodium bicarbonate and ketamine can reduce the incidence and severity of POST. The best results are seen with lignocaine with sodium bicarbonate and ketamine, with minimal side effects. Conclusion: Intracuff Ketamine could be a better alternative to gargle in reducing POST and needs further trial.

Key words: post operative sore throat, ketamine gargle, intracuff ketamine, intracuff lignocaine, sodium bicarbonate.

 

 

INTRODUCTION

Tracheal intubation is foremost cause of trauma to airway mucosa in patients undergoing surgeries under general anesthesia.Postoperative sore throat (POST) contributes to postoperative morbidity with incidence of 21 – 65% ^1,2,3 . Various studies have shown that POST is attenuated by topical spray of lignocaineto airway, inflation of ETT cuff with lignocaine alone ^4,5,6 or with Na bicarbonate ^6,7,8,9, Beclamethasone inhalation¹⁰. Intracuff drugs have been shown to diffuse across endotracheal tube cuff and produce effects topically. Canbay et al¹¹ in a recent study showed that preoperative Ketamine gargle reduces incidence of POST. We can also premise that Ketamine would diffuse across the cuff and possibly reduce POST.

 

MATERIALS AND METHODS

The study was conducted at Department of Anaesthesiology and Critical Care, VIMS, Bellary. Institutional Ethics Committee approval was taken. The study designed was a prospective, randomized, single blind comparative study. 100 patients of either sex, between the age of 18 and 50 years, of ASA 1/2 posted for elective surgical procedures under General Anesthesia, with orotracheal intubation were included in the study after obtaining informed written consent. Patients of ASA 3/ 4, difficult airway / multiple intubation attempts, with h/o sore throat, upper respiratory tract infections, h/o allergies/ bronchial asthma/ Chronic obstructive pulmonary disease were excluded from the study. Preanesthetic checkup was done with necessary investigations. Tab Diazepam 5mg was given orally on the night before surgery. Inj Atropine and Inj Ondansetron was given intravenously after shifting to operation theatre. Induction was done after injection of Fentanyl, Thiopentone sodium and Vecuronium.Orotracheal Intubation was performed using disposable cuffed PVC ETT of same brand no.7 for females/ no.8 for males. Patients were randomly allotted into one of the four groups having 25patients in each group.

Group A : Air

 Group L :Lignocaine 2% (2ml +NS)

 Group B :Lignocaine 2% (2ml +7.5%Sodium bicarbonate)

 Group K: Ketamine(20 mg +N S)

Correct inflation volume confirmed by auscultation for air leak over trachea.

Monitoring of SPo2, Non invasive blood pressure, Electrocardiography, ETCO₂ after intubation were done. Anesthesia was maintained with O₂-N₂O (34:66)/Vecuronium/0.5%- 1% Halothane/Fentanyl/Intermittent Positive Pressure Ventilation. Patients were extubated at the end of the surgery after giving reversal agents.

Primary Study Parameter : Sore throat - Incidence/severity(Mild,Moderate,Severe)

Secondary Study Parameters :

1. Hemodynamics at extubation

2. TUBE tolerance/Extubation time: Time patient could tolerate tube in situ, after reversal

3. Hoarseness, Dysphagia, PONV and cough

All the above parameters were noted at extubation and followed up for 24 hrs. The data obtained was entered in a proforma, tabulated and statistically analysed.

Statistical Analysis

All the parameters were recorded in the study Proforma, analysed and compared using Paired T test and Chi square test (SPSS Version 15)

*Statistically significant

** Statistically very significant

In present study we considered p value <0.05 as statistically significant and p value < 0.01 as statistically very significant.

 

RESULTS

Table 1: Age distribution among the groups

 

Table 2: Sex distribution among the groups

The group comparison was done by student t test, which demonstrated no significant difference in itsdistribution among 4 groups with regard to distribution of age and sex.

 

Table 3: Duration of surgery

The group comparison was done by student t test, which demonstrated no significant

difference in its distribution of surgical time among 4 groups.

 

Table 4: Basal Hemodynamic parameters

Basal hemodynamic parameters like PR, SBP, DBP, SPo2 were comparable in all the four groups.

 

Table 5: Comparison of Basal PR with PR at extubation

There was a statistically significant increase in PR in Group A and Group K from basal value to extubation value. In the other two groups there was no statistically significant increase in PR.

 

Table 6: Comparison of Basal SBP with SBP at extubation

There was a statistically significant increase in SBP in Group A and Group K from basal value to extubation value. In Group L and Group B there was no statistically significant increase.

Table 7: Comparison of Basal DBP and DPB at extubation

There was statistically very significant increase in DBP at extubation in Group A and Group K ,with p value 0.00 and also significant increase in DBP in Group L (p -0.044) and Group B (p-0.047)

 

Table 8: Comparison of Volume inflated, deflated and diffused

The volume of drug used to inflate the cuff were comparable in Group L, Group B and Group K and the volume of air used to inflate the cuff in Group A is more when compared to other three groups. There is no diffusion of air across the cuff. Volume diffused is more in Group B and Group K when compared to Group L and it is comparable in Group B and Group K.

 

Table 9: Comparison of Extubation interval

Tube tolerance was better in Group B and Group K patients when compared to Group A and Group L patients. There was no difference in tube tolerance between Group A and Group L (p value 0.590) and between Group B and Group K (p – 0.709). There was a statistically significant difference in tube tolerance between Group A and Group B (p – 0.027). There was a statistically very significant difference between Group A and Group K (0.005), between Group L and Group B (0.00) and between Group L and Group K (0.001).

 

Table 10: Incidence and Severity of POST

Incidence of POST was maximum in Group A and also the severity. Group L had more incidence of POST when compared to Group B and Group K and the incidence is comparable between Group B and Group K. Group A had mild to severe POST and none of the other 3 groups had severe POST. Group B had only mild POST whereas Group L and Group K had mild to moderate POST.

Table 11: Comparison of other side effects

Incidence of side effects were comparable in Group A and Group L. Group B and Group K had comparable incidence of side effects except for dysphagia. Group K had maximum incidence of dysphagia when compared to other three groups.

DISCUSSION

General anesthesia with Endotracheal intubation is associated with undesirable effects at and after extubation. Localside effects mainly are Sore throat, hoarseness, dysphagia, cough, etc^1,2,3. Systemic effects are tachycardia, hypertension, dysrhythmias⁶, bronchospasm, cough etc.POST contributes to postoperative morbidity with incidence of 21 – 65% ^1,2,3.This can be attenuated by various methods. Lignocaine added to the ETT cuff can act as a reservoir, slowly diffusing across the cuff, producing local effects ^12,13.Alkalinized Lignocaine can have better effects by increasing nonionized fraction of Lignocaine thereby increasing its diffusion across cuff^7,8,12. Preoperative Ketamine gargle¹¹ has also shown to reduce incidence /severity of POST through antiinflammatory action on peripheral NMDA receptors. Based on these studies and Ketamine Gargle study and on the premise that Ketamine would also diffuse across the ETT cuff, we compared the attenuation of POST with intra cuff Lignocaine, Lignocaine with Sodium Bicarbonate , Ketamine and Air. All the groups were comparable with respect to age and sex distribution.

Navarro et al 1997 conducted a study to compare POST in air and lignocaine and found that incidenceof POST was significantly different at the 24-hour evaluation (59% air vs. 32% lidocaine, p = 0.01). Severity of sore throat was significantly worse with air at all evaluation periods. This is similar to what is found in our study 40% air vs. 32% lignocaine. Estebe et al 2005compared group air, group large dose (8.4%) NaHCO3 with lignocaine and group small dose (1.4%) NaHCO3 with lignocaine and found that both NaHCO3 with Lignocaine groups had significant reductions in sore throat during the 24-hpostoperative period (P _ 0.0001). No significant difference was reported between theuse of 8.4% and 1.4% NaHCO3 to alkalinize lignocaine in VAS scores for sore throat. Their study established that alkalinization of lignocaine improves the diffusion of lignocaine across the cuff membrane. The results were similar in our study where incidence of POST in Group B was significantly lower than in Group A. Canbay et al 2008studied the effect of ketamine gargle and compared with saline instillation in the cuff. The incidence of POST was higher in saline group compared with ketamine gargle group at 0, 2, and 24 h (P,0.01). Significantly more patients suffered severe POST in saline group as compared to ketamine gargle group in first 24 h. NMDA receptor antagonists are implicated with antinociception. They attributed the reduced incidence of POST in ketamine gargle group to its action on peripheral NMDA receptors and anti-inflammatory action of ketamine. The results were similar in our study where Group K (16%) had lower incidence and severity of POST when compared to air group(40%).Fai Lam et al 2015 reviewed nineteen trials, which comprised 1566 patients. This systematic review and meta-analysis demonstrates that intracufflidocaine used in patients receiving general anesthesia through ETT is associated with significantly reduced incidence of POST, reduced POST severity as evaluated by pain scores at 1 and 24 h postoperatively, and lower risk of other postintubation emergence phenomena such as coughing, agitation, and dysphonia when compared with other interventions such as intracuff air or inflated saline. Both alkalinized and non-alkalinized lidocaine in the subgroup analyses showed significant benefits in emergence phenomena prevention compared with the control. In our study we found that incidence of POST was lesser in Group L (32%) compared to Group A (40%), further showed that POST was lesser after alkalinization of lignocaine (16%).

Changes in PR, SBP, DBP from basal value to at the time of extubation was significantly higher in Group A and K. There were no significant changes in the other two groups. Increase in Group K can be attributed to sympathomimmetic effect of ketamine. Similar increase in hemodtnamic parameters in placebo group was found in Estebe et al 2002 study. Tube tolerance/extubationtime is defined as ‘the time patient could tolerate tube in situ, after reversal’. Tube tolerance was better in Group B and Group K patients when compared to Group A and Group L patients. There was no difference in tube tolerance between Group A and Group L (p value 0.590) and between Group B and Group K (p – 0.709). Group B and K patients tolerated the tube in a significantly better way than Group A patients (p – 0.027 n 0.005 respectively). Similarly Group B and K patients had statiscically significant better tube tolerance compare to Group L (p – 0.00 n 0.001 respectively).Overall Group B and K patients had better tube tolerance and smooth emergence. This result was similar to that shown in other studies like Navarro et al, Estebe et al, Canaby et al and also metaanalysis by Fai Lam et al.

The incidence of side effects like dysphagia, hoarseness, PONV, cough were less in bicarbonate group when compared to other three groups. Their incidence was maximum in air group. Above mentioned studies also had shown similar results. Having prolonged extubation time (tube tolerance) Group B and K showed minimal side effects.

 

CONCLUSION

Extubation is associated with undesirable effects, both systemic and local, POST being one of the most common morbidities which can be preventedby various methods.In present study we compared the efficacy of intracufflignocaine with and without sodium bicarbonate and ketamine in reducing POST and other side effects. Sore throat was minimal in Group B and K, of mild to moderate severity. Extubation interval was high in Group K and B as compared to other groups. Group B showed best results considering all study parameters. IntracuffKetamine could be a better alternative to gargle in reducing POST and needs further trials.

 

ACKNOWLEDGMENT

I sincerely thank Dr S Balabhaskar and Dr N kiranchand for their guidance and support in conducting this study and bringing out this article.

 

REFERENCES

• Loser EA, Bennett GM, Orr Dl, Stanley TH. Reduction of postoperative sorethroat with new endotracheal tube cuffs. Anesthesiology 1980, 52: 257-9.
• Christensen AM Willemoes- Larsen H. Lundby L, Jakobsen KB. Postoperative throat complaints after tracheal intubation. BJA 1994; 73: 766-7.
• Barash PG, Cullen BF, Stoelting RK. Clinical Anesthesia. 4^th edition. Lippincoiott Williams; 2001.
• NavarroRM, BaughmanVL. Lignocaine in the endotracheal tube cuffs reduces post operative sore throat. J ClinAnesth 97; 9(5): 394-7.
• Fagan C, Frizelle HP, Laffey J, Hannon V, Carey M. The effects of intracufflidocaine on endotracheal tube induced emergence phenomenon after general anesthesia. AnesthAnalg 2000; 91: 201-5.
• Dollo G, Estebe JP, Le Corre P, Chevanne F, Ecoffey C, Verge RL Endotracheal tube cuffs filled with lidocaine as drug delivery system: in vitro and in vivo investigations. Eur J PharmSci 2001; 13(3): 319- 23.
• Estebe JP, Dollo G, Le Naoures A, Chevanne F, Le Verge R et el. Alkalinization of intracufflidocaine improves endotracheal tube induced emergence phenomenon. AnesthAnalg 2002; 94: 227-30.
• Estebe JP, Delahaye S, Le Corre P, Dollo G, Le Naoures A, Chevanne F, et al. alkalinization of intracufflidocaine and use of gel lubrication and use of gel lubrication protect against endotracheal tube induced emergence phenomenon BJA 2004; 92 (3); 361- 6.
• Estebe JP , Genilli M, Le Corre P, Dollo G, Chevanne F, Ecoffey C, Alkalinization of intracufflidocaine: Efficacy and saftey. AnesthAnalg 2005; 101(5); 1536- 41.
• Tel Hakim M. Beclomethasone prevents postoperative sorethroat. ActaAnesthesiol Scand 1993; 37: 250-2.
• O. Canbay, N Celebi, A Sahin, V Celiker, S Ozgen and U. Aypar.Ketamine gargle for attenuating POST; BJA 100 (4); 490- 4 (2008).
• Huang CJ, Tsai MC, Chen CT, Cheng CR, Wu KH, Wei TT. In vitro diffusion of liodocaine across endotracheal tube cuffs. Can J Anesth 1999; 46(1): 82- 6.
• Sconzo JM, Moscicki JC, Difazio CA. In vitro diffusion of lidocaine across endotracheal tube cuffs. RegAnesth 1990; 15: 37- 40.
• Soltani HA, Aghadavoudi O. the effect of different lidocaine application methods on postoperative cough andsorethroat. J ClinAnesth 2002, 14: 15- 18.
• Higgins P, Chung F, Mezei G. Postoperative sorethroat after ambulatory surgery. BJA 2002; 88(4); 582- 4.
• Coombs X, Schawliege F, Peyrouset O, Motamed C, Kierov K, Bhonneur G et al. intracuff pressure and tracheal morbidity- influence of filling cuff with saline during nitrous oxide anesthesia. Anesthesiology 2001, 95:1120- 4
• Fai Lam, Yu-Cih Lin, Hsiao-Chien Tsai, Ta-Liang Chen, Ka-Wai Tam, ChienYu Chen Effect of IntracuffLidocaine on Postoperative Sore Throat and the Emergence Phenomenon: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. PLOS ONE, August 19, 2015, 1-17.