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CorrespondenceTHE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 13, NO.1, 2000

Caesarean sections on the rise

This has reference to the paper by Paiet al.-A high rate of Caesareansections in an affluent section ofChennai: Is it a cause for concern?'Pai's article shows a Caesearean section (CS) rate of 45%, which isevidently a matter of concern for policy-makers and medical profes-sionals. Although we neither have a national norm nor any reliableestimate of CS rate at the regional or national level, emerging interna-tional literature suggests that 45% is much higher than the ratesprevailing in most developed and developing countries. Belizan etal.2 reported that in 12 out of 19 Latin American countries, the CS rateranged from 16% t040%. In the other 7 countries, the CS rate was lessthan 15%, which is the rate set as a norm for Latin American countriesby the World Health Organization (WHO).

Even if we were to take the highest rate of 40% prevailing 'in theLatin American countries as our norm, the prevailing rate in Chennaiamong the population studied by Pai et al. is alarming. 'The mostuseful observation from [this] survey', as Pai et al. point out, 'is theCS rate itself, which requires further investigation.

I wish to share the results of two studies, one hospital-based andthe other populationlhousehold-based, which I hope would contri-bute to a fruitful discussion among all concerned people:

1. As part of a study conducted in late 1996 on private hospitals inChennai city, we collected from the Corporation Health Officer'sBirth Certificate Records names of 285 women who had deli veredin the previous 3 months in various hospitals located in differentzones of the city. Of these, 249 had delivered in 20 differentprivate hospitals, and the remaining 36 in 3 maternity centres runby the Corporation. Using the addresses given in the Birth Certi-ficate Records, these women were tracked and interviewed at theirhomes. Our survey showed that out of the 249 deli veries in privatehospitals, 113 (45%) were by CS. The survey also revealed thatthere were hospitals where at least 80% of deliveries were by CS.No CS was reported among those delivered in maternity centresmaintained by the Corporation, though they are designed andequipped to undertake CS.

2. In anotherrecenthousehold-level study (Murleedharan VR, SureshSaradha. 'Health status, socio-economic conditions and expen-ses for delivery: A household analysis of pregnant women inDindugal town, Tamil Nadu 1999,' unpublished data) conductedamong slum women in Dindugal town (in Tamil Nadu), wetracked all pregnant women in the slum areas between May 1998and September 1999. Out of 1116 deliveries (done at home, or inprivate or public institutions), 6.5% were CS. However, amongthose (392) who had delivered in private hospitals, 12% were byCS.

The findings of the second study are noteworthy, because they aredrawn from the entire slum population of an urban town, largelyrepresenting the poorest sections of society. Belizan et al. and otherresearchers support the view that CS rate is positively correlated withsocio-economic conditions. Our studies, together with Pai et ai.'sseem to support such findings, although in a crude manner.

Pai et al. do not show CS rate according to private and publichospitals. Very few would dispute that the CS rate in private hospitalsis higher than in public hospitals. However, it is important to separatethe two (private and public hospitals), as this information couldprovide important clues to the dynamics of the private health caremarket. Strictly speaking, we should then proceed to follow up out-comes in private and public hospitals and obtain data on patients'socio-economic and other characteristics. Only then can we inquire

further as to whether we indeed are 'having an unjustifiably high rateof CS' or not and examine the causes for the same.

The adverse effects of such high CS rates are well-recorded in theliterature. In a country like India that can ill-afford wastage of medi-cal resources, it is time for health policy-makers to understand such'disturbing' phenomena and address them at the earliest. Evidently,part of the solution lies in overhauling the entire structure and func-tioning of the private and public health care systems in India.

22 December 1999 V. R. MuraleedharanDepartment of Humanities and Social Sciences

Indian Institute of Technology, MadrasChennai

Tamil Nadu

REFERENCESPai M, Sundaram P, Radhalcrishnan KK, Thomas K, Muliyil JP. A high rate ofCaesarean sections in an affluent section of Chennai: Is it a cause for concern? NatlMed} India 1999;12:156-8.

2 Belizan JM, Althabe Fernando A, Barros FC, Alexander S. Rates and implicationsof caesarean sections in LA: Ecological study. BM} 1999:319:1397-402.

Medical students: Their attitudes to organ donationand transplantation

Rapid advancement in technology relating to transplantation oforgans and tissues has created a demand for organs and tissues farexceeding their availability. This has led to shortages, illegal pro-curement and altruism. 1 Due to these reasons, a large number ofcountries in the world have been forced to enact laws to regulate thepractice of transplantation. In India, a law was passed in 1994, wasnotified and came into force from February 1995 called the Trans-plantation of Human Organs Act, 1994.2 This Act facilitates theretrieval of organs from brain dead persons.

The magnitude of organ retrieval is heavily dependent upon theattitude of the public and medical professionals.' The attitude ofmedical students can have far-reaching effects on increasing organdonations and thus transplantations, as they occupy a unique positionbetween the lay public and the qualified professional. I conducted asurvey of 200 medical students belonging to the third and fourthyears of the MB,BS course at the University College of MedicalSciences, Delhi during 1996, using a multiple choice questionnaire.Sixty-six per cent of students responded by returning the completedquestionnaire. Thirty-two per cent of students were aware about thelaw on organ donation and transplantation in our country. Only 7.5%students were satisfied with the level of knowledge they possessed onorgan transplantation. More than 80% were willing to donate organs,only 10% were unwilling while the rest were not sure.

The fact that a large number of students were not aware about thelaw regulating organ transplantation may be attributed to the recentnature of the law and its non-inclusion in the undergraduate curricu-lum. This could be one of the reasons for the low level of organ dona-tion in our country, and this suggests that information about this lawshould be included in the undergraduate curriculum. The relativelyhigh percentage of willingness for organ donation can be explainedon the basis of the specialized group-based nature of the study.

CORRESPONDENCE

The survey clearly demonstrates that medical students lack suffi-cient knowledge on the issue of organ donation but have a positiveattitude towards it. One of the ways forward could be to enhance theknowledge of medical students during their undergraduate days, sothat when they become doctors they are aware of the legal status, aremotivated and able to motivate the public to be actively involved inthe process of organ donation.

23 December 1999 S. K. VermaDepartment of Forensic Medicine and Toxicology

University College of Medical SciencesDelhi

REFERENCESI Perkins HS. Tolle SW. The shortage of organs for transplantation. N Eng/ ] Med

1992;326: I025.2 The Transplantation of Human Organs Act, 1994.3 Prottas J, Batten HL. Health professionals and hospital administrators in organ

procurement: Attitudes. reservations and their resolutions. Am J Public Health1998;78:642-5.

Convulsions in non-epileptics due to mefloquine-fluoroquinolone co-administration

Mefloquine is being increasingly used for the treatment of chloro-quine-resistant Plasmodium Jalciparum (P. Jalciparum) malaria. In1989, the World Health Organization (WHO) initiated reporting andinvestigation of neuropsychiatric adverse reactions to the drug.These adverse reactions, which include seizures, are now well docu-mented following the use of the drug both in epileptic and non-epileptic patients.' Mefloquine has been in use in India for severalyears and in an attempt to monitor adverse effects to this drug seenby our physicians, a questionnaire on the drug prepared by ouradverse drug reaction monitoring centre (WHO special centre) wasmailed to 1000 physicians of Maharashtra. The information soughtto be obtained was regarding the number of patients treated with thedrug, indication for use, dose used, number of adverse reactions seenwith details and the outcome. A total of 100 physicians replied.

Three physicians reported convulsions following the use of mef-loquine in patients who were non-epileptic, with no family history ofepilepsy and no obvious predisposition. Between them, these threephysicians had treated a total of ISO cases. On examining thesereports carefully, it was seen that each of these 3 patients (2 men and1 woman), had received one fluoroquinolone either prior to or alongwith the administration of mefloquine. The fluoroquinolones weresparfloxacin, ofloxacin and ciprofloxacin, respectively. Ofloxacinwas given 2 days prior and ciprofloxacin and sparfloxacin were giventogether with mefloquine. The fluoroquinolones and mefloquinewere given for the treatment of fever of unknown origin. The diag-nosis of fever was later established to be due to P. vivax in one, P.

Jalciparum in another and was not established in the third. None ofthe patients had severe or complicated malaria. Other adverse eventsnoted (by all practitioners) in the survey were nausea, vomiting,diarrhoea, haematemesis, gastritis, diplopia, tinnitus, dizziness, macu-lopapular rash, aberrant atrioventricular conduction, visual distur-bances and stomatitis.

Fever of unknown origin can have multiple causes.' The absenceof laboratory facilities in several parts of India compounds theproblem, making prescribing empirical. India is endemic for malariaand typhoid and co-existence of the two has been documented.'

Neuropsychiatric toxicity including convulsions due to fluoro-

47

quinolones has been reported. To the best of our knowledge, this isthe first report of this combination leading to convulsions in non-epileptic patients. Drug-resistant malaria and typhoid are widelyprevalent in India and this important preventable adverse eventshould be borne in mind. Physicians should make every attempt toestablish a definitive diagnosis prior to the co-administration ofagents for malaria and typhoid. In the eventuality of a requirement forempirical therapy, drugs with toxicities similar to those of mefloquineand fluoroquinolones should not be co-administered.

25 December 1999 S. S. MangalvedhekarN. J. GogtayV. R. Wagh

M. S. WaranD. Mane

N. A. KshirsagarDepartment of Clinical Pharmacology

K.E.M. HospitalParel

MumbaiMaharashtra

REFERENCESGarg MR, Gopinathan N, Kshirsagar NA. Mefioquine induced grand-mal seizure ina case of uncomplicated falciparum malaria.J Assac Physicians India 1996;44:750.

2 Dek.leijn EM, Vandenbroucke JP, van der Meer JW. Medicine 1997;76:392-400.3 Singh PS. Co-existence of enteric fever with malaria.J Assac Physicians India 1995;

43:71-2.

Provide water, health and education-not nuclearweapons

It is a matter of concern that the governments of India and Pakistanappear to be set on the path of nuclear weaponization. The horror ofthe bombing of Hiroshima and Nagasaki seems to be fading frommemory, and policy-makers are feeding the public with myths andhalf-truths about nuclear weapons.

As physicians, we are committed to protecting, preserving andimproving the quality of life of individuals and societies. We are,therefore, extremely disturbed by the recent developments in thesubcontinent and call on all citizens to raise their voices and halt thisprocess. Once committed to actual weaponization, it will be exceed-ingly difficult to step back. The human, environmental, social andeconomic costs will be unbearably high, and weare likely to be drawninto an accelerating race of weaponization with disastrous conse-quences.

The horrific, uncontrollable and transgenera-tional nature ofdamage caused by nuclear weapons have been extensively docu-mented. It is important to remember and reiterate that they are like noother weapons. Their effects are devastating and indefinite. Funda-mentally, they are biological weapons. The radiation they unleashhas terrible consequences. There is no treatment for radiation dam-age. All the so-called 'treatments' are merely supportive, waiting forthe body to regenerate. Beyond certain levels of radiation, death iscertain, sometimes mercifully quick, otherwise painful and linger-ing. Those who survive may be badly impaired. These weaponstransgress every moral, ethical and humanistic principle. Their usecannot be condoned by even the most liberal interpretation of any'code of warfare'. Most apologists for nuclear weaponization pro-claim that they are for deterrence only. However, this is a completelyfalse position. Possession of nuclear weapons by any two countries

48 THE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 13, NO.1, 2000

does not decrease their hostility or their propensity to engage in non-nuclear conflicts. The tragedy at Kargil was the most recent exampleof this fact. An extreme illustration was the prolonged hostility of thecold war during which the former Soviet Union and the USA createdan ever-increasing arsenal of nuclear weapons, enough to annihilateall the peoples of the world many times over.

The principle of 'no first use' is also of no great value. Thisimplies a retaliatory strike capability, thereby diverting attentionfrom the catastrophic consequences of any nuclear strike. It giveslegitimacy to the completely false and suicidal concept of a 'limitednuclear war' which is itself part of the fallacy of deterrence.

The ethical, moral and ecological imperatives for discarding nuc-lear weapons are closely intertwined with the economic imperative.Conservative estimates suggest that about 1% of the Gross DomesticProduct (GDP) over a period of 10 years will be needed to finance aminimum nuclear weapons programme. This money will have to bediverted from other sectors. Past experience suggests that it is thebudget for sectors of human development, such as health and educa-tion, that will be reduced to pay for the weapons. To make the figuresmore understandable, the cost of the 'minimum deterrent' is equal tothe cost of providing universal access to primary education for allchildren between the ages of six and fourteen. The cost of eachnuclear arm 'Agni' (Rs 45 million) can finance the annual operationof 13 000 primary health centres.

Both India and Pakistan are among the poorest countries in theworld. The Human Development Index, which indicates the qualityof life in about 180 countries worldwide, ranks both countries in the130s to 140s-very near the bottom. What we need to focus on isproviding water supply, health and educational facilities for all ourpeople. What we do not need is an expensive nuclear weaponsprogramme that will aggravate existing tensions and divert scarceresources from far more important tasks.

3 January 2000 Thomas GeorgeRailway Hospital

PeramburChennai

Tamil NaduShriram Rajagopal

AdyarChennai

Tamil Nadu(on behalf of Physicians for Peace)

Yet to surface problems of corneal refractive surgery

Keratorefractive surgery is evolving at an astonishing pace. With anynew surgical technique, there are implicit unknown short and longterm complications and consequences. The short term consequencesof refractive surgery relate to its effect on the quality of vision suchas contrast sensitivity, glare, night vision, etc.' The long term conse-quences are yet to be known. The majority of refractive surgical pro-cedures are being performed on individuals currently between 20 and40 years of age. As this population ages, we are likely to encountercurrently unknown problems. It is imperative that some of the likelyconsequences should be thought about so that methods to tackle themcould be evolved pro-actively.

Effect of refractive surgery on eye bankingRefractive surgical techniques produce changes in the curvature,

thickness, shape and structural and biochemical composition of thecornea. Screening potential donor tissue by slit lamp alone, which isthe conventional and standard method, may not detect prior laserintrastromal keratomi1eusis (LASIK), photorefractive keratectomy(PRK) or automated lameller keratectomy (ALK). Do we need toshift to more sophisticated means of screening potential donors? Dowe need to screen and study the curvature of potential donors byvideokeratography? In India, affordability and availability of suchsophisticated equipment will be a problem. Are such corneas fit to beused? If not, one can imagine the impact on the backlog of cornealblindness, especially in India. It has been estimated that in India thereare about 1 million corneal blind people, out of which 200 000 arebilaterally blind. Even now, on an average, only 13 000 eyes arebeing donated in a year and only 7000 eyes are being grafted. Thus,at this rate, we would need another five decades to make up the back-log.? Therefore, discarding all corneas which have undergone refrac-tive surgery would not be a feasible option. Also, studying the curva-ture of the cornea in an enucleated eye by videokeratography is noteasy. The results will depend on how well the eye is held while underobservation, without inducing curvature changes. Therefore, an eyeholder which fulfils such needs would have to be designed. If suchcorneas are to be used, we would either need to change currentl y prac-ticed surgical techniques or be prepared to have unexpected refrac-tive results. The use of such donor tissue and the likely decentrationof the flattened or in the case of hyperopia, steepened optical zone inrelation to the entrance pupil, may have important effects on therefractive outcome in corneal transplant patients. Even if the graft iswell centred over the entrance pupil, unexpected central cornealflattening or steepening may result in significant ametropia follow-ing penetrating keratoplasty or triple procedures.

Ophthalmologists need to think about this problem and makeefforts to promote public awareness so that information regarding thedeceased having had keratorefractive surgery is provided by relativesat the time of eye donation.

Effect of refractive surgery on calculation of the power ofintraocular lens (IOL)IOL is a standard and established means of rehabilitating aphakicpatients. Currently, various formulae are used to calculate the powerof the present-generation IOLs of patients who have an untamperedcornea. As the population of patients who have had refractive surgeryincreases and these patients age, they will inevitably require cataractextraction and IOL implantation. A few small case series of conven-tional extracapsular cataract surgery or phacoemulsification follow-ing radial keratotomy (RK)3-5 or PRK6 are available which highlightthe likely problems ophthalmologists will face in the future.

Much of the error inherent in the calculation of the power of theIOL following keratorefractive surgery arises from difficulties inaccurately estimating the corneal power of the eye. Many of theinstruments used to measure corneal power assume central sphericityand a radius of curvature of the posterior cornea to be 1.2 mm steeperthan the anterior radius. Following different forms ofkeratorefractivesurgery, there may be clinically important irregular astigmatism orasphericity, particularly in patients undergoing RK with a smalloptical zone. Most IOL power calculations use a net index of refrac-tion of 1.33 and the anteriorradius ofthe cornea as 7.8 mm to estimatenet corneal power. However, in PRK or LASIK, there is a flatteningof the anterior corneal surface with little or no impact on the posteriorradius. This change in relationships leads to inaccurate estimations ofnet corneal power by videokeratography, where a net index of refrac-tion of 1.33 will overestimate the change in the central refractivepower of the cornea by 14% following LASIK or PRK.7 Thus,measurement of both the anterior and posterior corneal curvature inrelation to the entrance pupil will become a necessity. This willrequire the use of videokeratography, which is expensive and not

CORRESPONDENCE

widely available in India. Corneal power can be determined by fittinga hard plano contact lens, manual keratometry or videokerato-"graphy. While the first method can be used only if the ocular mediapermits refraction, manual keratometry is considered to be the leastaccurate of all because it measures only four points approximately1.5 mm from the corneal apex. This measured zone may be moreperipheral to the central flattened area, especially following smalloptical zone RK leading to a lower calculation of the power of theIOL and postoperative hyperopia. Occurrence of transient flatteningof the cornea post phacoemulsification has been reported in eyes withprevious RK4.5but not after PRK and LASIK. Moreover, dehiscenceof the radial keratotomy incision during clear corneal cataract sur-gery has also been reported."

Finally, the long term effects ofPRK and LASIK on the stabilityof refraction are not known and these could also have an impact onIOL power calculations and selection of the postoperative target ofrefraction. Moreover, some patients with preoperative lenticularastigmatism may have been treated with radial and astigmatic kera-totomy, LASIK or PRK with concurrent laser or incisional astigmaticsurgery. Such patients may have a suboptimal outcome followingphacoemulcification with IOL implantation, or require additionalrefractive surgery or modified cataract surgery as the IOL implantwill not have the astigmatic properties of their crystalline lens. Theseproblems will be faced by ophthalmologists practising in Indiaearlier than colleagues in the rest of the world, because cataractappears a decade earlier in the Indian population as compared to thewestern population,

Effect of refractive surgery on intraocular pressure (lOP)measurementsApplanation tonometric readings are affected by the corneal curva-ture and thickness. The Goldmann applanation tonometer underesti-mates the lOP in thinner corneas and overestimates it in thickercorneas." Other factors, such as the physical characteristics and dis-tribution of collagens and glycosaminoglycans composing the cor-nea or the presence or absence of structures such as Bowman's mem-brane may also affect the resistance ofthe cornea to indentation. Thestructure, shape and thickness of the cornea is altered after PRK andwould therefore be expected to affect the accuracy of applanationtonometry. A 0.5 mmHg mean reduction in tonometer readings isassociated with a 23 urn reduction in the corneal thickness followingPRK.IO This finding may be of importance at higher depths ofablation, as in the case of higher degrees of myopia treated by LASIKand PRK surgery. Similar results have been reported after LASIKalso, II though the cause remains to be established. The observedeffect may be greater at a higher lOP. The small change in lOP

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measurement following PRK is probably not enough to alter atherapeutic decision in an individual patient known to have glaucomaof the angle closure type or open angle glaucoma with high lOP.However, it might pose problems in the management of normal ten-sion glaucoma. Also, it might delay the recognition of glaucoma if thelOP measurement is taken as the main screening tool for initiating theevaluation of a patient suspected to have ocular hypertension orglaucoma.

Changes in the pattern of contact lens fittingLoss of the best corrected visual acuity after different types of cornealrefractive procedures is well documented. If it improves with acontact lens, fitting such patients is difficult, especially after RK. 12

How the fitting of a contact lens is going to differ in patients afterPRK and LASlK remains to be clearly established.

Future research is needed in these areas which could have aprofound impact on public health, especially of an ageing population,

18 December 1999 Narottama SindhuSudarshan Khokhar

Dr R.P. Centre for Ophthalmic SciencesAll India Institute of Medical Sciences

New Delhi

REFERENCESMaquire LJ. Keratorefractive surgery success, and the public health.Am J Ophthalmol1994;117:394-8.

2 NSPB study, Govt of India, 1992.3 Hoffer KJ. Intraocular lens power calculation for eyes after refractive keratotomy.

J Refract Surg 1995;11:490-3.4 Koch DD, Liu JF, Hyde LL, Rock RL, Emery JM. Refractive complications of

cataract surgery after radial keratotomy. Am J OphthalmoI1989;108:676-82.5 Celikkol L, Pavlopoulos G, Weinstein B, Celikkol G, Feldman ST. Calculation of

intraocular lens power after radial keratotomy with computerized videokeratography.Am J OphthalmoI1995;120:739-50.

6 Lesher MP, Schumer J, Hunkeler JD, Durrie DS, McKee FE. Phacoemulsificationwith intraocular lens implantation after photorefractive keratotomy: A case report.J Cataract Refract Surg 1994;20 (Suppl):265-7.

7 Holladay IT.lntraocular lens power calculations for cataract and refractive surgery.In: Seradarevic ON (ed). Refractive surgery: Current technique and management.New York.Igaku-shoin, 1997:183-93.

8 Budak K, Friedman NJ, Koch DO. Dehiscence of radial keratotomy incision duringclear corneal cataract surgery. J Cataract Refract Surg 1998;24:278-80.

9 Ehlers N, Bramsen T, Sperling S. Applanation tonometry and central cornealthickness. Acta Ophthalmol 1975;53:34-43.

IO Mardelli PG, Piegenga LW, Whitcare MM. The effect of photorefractive keratotomyon Goldmann applanation tonometry. Ophthalmology 1996;103 (Suppl):134.

II Fournier AV, Podtetenev M, Lemire 1, Thompson P, Duchesne R, Perreault C, et al.Intraocular pressure change measured by Goldmann tonometry after laser in situkeratomileusis. J Cataract Refract Surg 1998;24:905-10.

12 Lee AM, Kastl PRo Rigid gas permeable contact lens fitting after radial keratotomy.CIAO J 1998;24:33-5.