About us |  Subscription |  Top cited articles |  e-Alerts  | Feedback |  Login   
  Home | Ahead of print | Current Issue | Archives | Search | Instructions Celebrating 60 Years   Print this article Email this article   Small font sizeDefault font sizeIncrease font size
 
 Official publication of All India Ophthalmological Society   Users Online: 91
  Search
 
   Next article
   Previous article 
   Table of Contents
  
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    [PDF Not available] *
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Material and methods
    Results
    Discussion
    Summary
    Acknowledgement
    References
    Article Tables

 Article Access Statistics
    Viewed1807    
    Printed35    
    Emailed0    
    PDF Downloaded0    
    Comments [Add]    

Recommend this journal

 


 
ARTICLES
Year : 1979  |  Volume : 27  |  Issue : 3  |  Page : 20-23
 

Effects of different types of pulmonary ventilation on intra-ocular pressure under general anaesthesia


1 Department of Ophthalmology, Calcutta National Medical College & Hospitals, Calcutta, India
2 Department of Anaesthesiology, Calcutta National Medical College & Hospitals, Calcutta, India

Correspondence Address:
P Mukherjee
Department of Ophthalmology, Calcutta National Medical College & Hospitals, Calcutta
India
Login to access the Email id


PMID: 511286

Get Permissions

 



How to cite this article:
Mukherjee P, Bose N, Mukherji R. Effects of different types of pulmonary ventilation on intra-ocular pressure under general anaesthesia. Indian J Ophthalmol 1979;27:20-3

How to cite this URL:
Mukherjee P, Bose N, Mukherji R. Effects of different types of pulmonary ventilation on intra-ocular pressure under general anaesthesia. Indian J Ophthalmol [serial online] 1979 [cited 2014 Oct 24];27:20-3. Available from: http://www.ijo.in/text.asp?1979/27/3/20/31219


The success of an intra-ocular surgery largely depends on the skill of an anaesthetist and on how best he can keep the patient quiet during and after surgery and can maintain the intra­ocular pressure sufficiently low during surgery.

One of the major factors during anaesthesia which may lead to significant alteration in the intra-ocular pressure is the type of breathing i.e., spontaneous and controlled ventilation, Duncalf and Weitzner[2], Utting and Davidson[5].

Hypoxia and hypercarbia increase the intra­ocular pressure while pulmonary hyperventila­tion, high arterial blood oxygen tension and low CO 2 tension lower the intra-ocular pressure, Utting and Davidson[5], Thornton and Levy[4].

In the present study it was contemplated to observe the effects of spontaneous and controlled ventilation on intra-ocular pressure under general anaesthesia during surgery which involv­es minimal trauma and minimal blood loss.


   Material and methods Top


The cases for this study were selected from the General Surgical Division of the Calcutta National Medical College Hospital. Study was carried out in forty normal male adult patients all of whom were normal except for the surgical ailments. The eyes of all these patients were normal. Patients were premedicated with Injection Pethidine hydrochloride (1 mg/kg body weight), Injection Promethazine 10.5 mg/kg body weight), Injection Atropine sulphate (0.65 mg) intramuscularly 45 minutes prior to the start of anaesthesia.

These patients were divided into two groups accord­ing to the type of ventilation adopted during maintenance of anaesthesia.

Group I -Spontaneous/assisted ventilation with Thiop­entone, Succinyl choline, N 2 0-0 2 , single intravenous dose of Pethidine hydrochloride (25 mg), intermittent gallamine as and when required.

Group II-Controlled ventilation with Thiopentone, Succinyl choline, N 2 0-0 2 , a single intraven­ous dose of pethidine hydrochloride (25 mg) and Gallamine as and when required through a C0 2 absorption circuit with an intentional leak.

Group 1:

Sleep was induced with Thiopentone t2.5% solution with an approximate dose of 5 mg/kg of body weight intravenously. Smooth atraumatic endotracheal intuba­tion was facilitated by intravenous injection of succinyl choline with an approximate dose of 1.5 mg/kg body weight. Intubation was done after spraying the larynx with 4% lignocaine hydrochloride and tube was lubrica­ted with lignocaine jelly to avoid bucking or coughing etc. A single dose of pethidine hydrochloride (25 mg) was given intravenously to provide analgesia. Anaes­thesia was subsequently maintained with N 2 0-0 2 and intermittent dose of gallamine (initial dose of gallamine was 1.5 mg/kg of body weight). Subsequently gallamine 15 20 mg was given intravenously as and when required.

The proportion of flow of N 2 0 to 0 2 was 6L: 3L. These patients were on spontaneous/assisted ventilation. When there was gross hypoventilation, respiration was assisted for the safety of the patient.

Tidal volume and minute volume were recorded both pre-operatively and also during anaesthesia.

Group II:

Induction and incubation were same as in group 1. A single dose of pethidine hydrochloride (25 mg) was given intravenously to provide analgesia. Anaesthesia was maintained with N20 and 0 2 4L: 2L and intermit­tent injection of gallamine (1.75 mg/kg body weight approx.) was given intravenously (1st dose). Gallamine was repeated as and when required in 20 mg intravenous dose. Respiration was controlled through a C02 absorp­tion circuit with an intentional leak. All attempts were made to prevent hypoxia and hypercarbia. Significant change in blood pressure, pulse or other clinical manifestations of shock were not observed in any patient in this series.

India-ocular pressure:

The intra-ocular pressure was measured in all the cases with a Schiotz Tonometer pre-operatively on the day before operation using 5.5 gm and 10 gm weights. Second reading was recorded after administering pre­medication. Third reading was recorded after intubating the patient. Fourth reading was taken when the action of succinyl choline wear off. Subsequent readings were taken at an interval of fifteen minutes during operation. In all the cases, the mean pressure was noted from the table for paired reading (Friedenwald).

Tidal volume, minute volume were recorded with Wright's respirometer both pre-operatively and during anaesthesia at different period of observation. Arterial blood 0 2 tension (Pa0 2 ) arterial blood CO 2 tension (PaC0 2 ) were done in some unselected cases for both groups pre-operatively and also during anaesthesia (15 minutes after intubation).


   Results Top


[Table - 1] shows that changes in intra-ocular pressure after premedication in both groups were lower than those of control values. After the action of succinyl choline wear off, the mean values of both the groups were same with the values after pre-medication.

It also shows that mean value of intra-ocular pressure in group I was significantly higher than that of group II. The `t' values between the two groups were highly significant.

[Table - 2] shows that tidal volume, minute volume after premedication were slightly lower than control value, and the mean values of tidal volume and minute volume 15 minutes after intubation and 30 minutes after intubation were much lowered than those of control values while the intra-ocular pressure raised significantly during that period.

Sample studies of blood gas analysis revealed that hypoxia and hypercarbia occurred in group I during anaesthesia. In group II neither hypoxia nor hypercarbia occurred during the period of anaesthesia, rather there was increased arterial oxygen tension and lowered arterial carbon-dioxide tension.


   Discussion Top


The type of ventilation during anaesthesia can play a significant role in alteration of intra­ocular pressure. Therefore, technique of anaesthesia is an important factor for the successful outcome of operation in ophthalmic surgery, Duncalf and Weitzner[2], Utting and Davidson[5].

In this study the group of patients who were on spontaneous/assisted ventilation, there was hypoventilation as indicated clinically (Wright's respirometer) by a low tidal volume and a low minute volume. Thus hypoventilation might be responsible for rise in intra-ocular pressure in this group of patients.

The tension of CO 2 in the arterial blood is a very important factor in controlling the intra­ocular pressure. A rise in arterial CO., tension increases the intra-ocular pressure in group I patients. On the contrary, in the group of patients on controlled ventilation the blood gas analysis shows a low arterial CO 2 tension and a high arterial oxygen tension which may be the cause of lowering the intra-ocular pressure in this group of patients as stated by Duncalf and Weitzner[2].

This hypoxia and hypercarbia might be increasing the cerebral blood flow by cerebral vasodilatation which ultimately increases the intracranial blood volume thus increasing the volume of blood in the eye and as there was no time for a compensatory decrease in the volume of aqueous, a rise in intra-ocular pressure resulted (Utting and Davidson)[5].


   Summary Top


On comparing the results of intra-ocular pressure of the two groups it was noted that the difference between the average values of intra­ocular pressure after premeditation and also after intubation was statistically insignificant. When the action of succinylcholine wears off, the difference between the values of intra-ocular pressure was also statistically insignificant but the difference between the average values of intra-ocular pressure was statistically significant 15 minutes after intubation, 30 minutes after intubation and 45 minutes after intubation.

It may be concluded from these observations, that the rise in intra-ocular pressure (Group 1) was significantly higher than that of Group II both clinically and statistically. This is in conformity with Duncalf and Weitzner[2] and Utting and Davidson[5].


   Acknowledgement Top


We are grateful to Prof. S.M. Lahiri, Head of the Department of Surgery, Calcutta National Medical College & Hospital for allowing us to carry out the work in his department and to Dr. H.N. Ghosh, Principal-Superintendent, Calcutta National Medical College & Hospital for his kind permission to publish this.

 
   References Top

1.Duke Elder, 1968, The physiology of the eye and of vision, Vol. IV, Henry Kimpton, London.  Back to cited text no. 1    
2.Duncalf, A. and Weitzner, S.W., 1963, Anaesth. & Analg., 42, 232.  Back to cited text no. 2    
3.Goldsmith Eric, 1967, Anaesth. & Analg. Cur. Res., 46, 557  Back to cited text no. 3    
4.Thornton, J.A. and Levy. C.J. 1974, Techniques of Anaesthesia. 263, Chapman and Hall, London.  Back to cited text no. 4    
5.Utting and Davidson, 1974, Quoted from Cecil Gray, T. and Nunn, J.F. 1971, General Anaes­thesia. Vol 2, 3rd Ed., p. 448. Butterworth & Co.  Back to cited text no. 5    


    Tables

[Table - 1], [Table - 2], [Table - 3], [Table - 4]



 

Top
Print this article  Email this article
Previous article Next article

    

© 2005 - Indian Journal of Ophthalmology
Published by Medknow

Online since 1st April '05