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S
urgical
treatment
of
morbid
obeSity
:
implicationS
to
pregnancy
It is estim a ted tha t over 1 billion people a re overweight or obese worldwide.1 Currently, obesity a ffects a bout 1 /3 of the
U.S. a dult popula tion older tha n 2 0 yea rs, which a dded up to 3 2 .6 % of overweight individua ls a nd 5 .9 % of m orbidly obese people, m a ke up a tota l of m ore tha n 7 0 % of a dults with a BMI equa l to or grea ter tha n 2 5 kg/m2 in the USA. From 1 9 6 0 to
2 0 0 6 , the preva lence of obesity a m ong U.S. people a ged 2 0 to 7 4 yea rs increa sed from 1 3 .4 % to 3 5 .1 %.2 It is estim a ted tha t
a pproxim a tely 1 0 m illion individua ls ha ve a BMI between 3 5 a nd 4 0 kg/m2.3 This proportion is increa sing gra dua lly in both
sexes in a ll a ge groups, pa rticula rly in children a nd a dolescents, in a ll ra cia l a nd ethnic groups, a nd in a ll socia l a nd econom ic levels.4 The World Hea lth Orga niza tion estim a tes tha t in 2 0 1 5
a round 5 4 % of U.S. wom en will be obese.
Ba sed on these da ta , we ca n get a n idea of the extent to which obesity a ffects the entire Western world. In Europe, da ta a re a lso a la rm ing, with m ore tha n ha lf of the individua ls being considered overweight a nd obese.
In Bra zil, IBGE da ta for 2 0 0 3 showed tha t 4 0 % of a dults older tha n 2 0 yea rs were overweight a nd 1 1 % of the popula tion wa s obese.5 In this period, m orbid obesity rea ched 0 .6 9 % of
the a dult popula tion, or a bout 6 0 0 ,0 0 0 people. In the la st three deca des, this popula tion increa sed 2 5 5 %.1
More recent da ta from the Ministry of Hea lth da ted of 2 0 0 9 show tha t 4 3 .3 % of the popula tion is overweight. This increa se wa s seen m a inly in m en, 4 7 .3 % com pa red with 3 9 .5 % of wom en, with preva lence in the South region. In Porto Alegre, 4 9 % of a dults a re overweight a nd 1 5 .9 % a re obese.6
In Bra zil, obesity ha s increa sed in both sexes, currently a ffecting 1 3 % of the a dult popula tion, with 1 2 .4 % of m en a nd 1 3 .6 % of wom en. The a ge group with the highest concentra tion of obese individua ls is between 4 5 a nd 5 4 yea rs of a ge.5
Obesity wa s rega rded a s a disea se typica l of developed countries; however, the globa liza tion of ha bits tha t encoura ge a sedenta ry lifestyle a nd the increa sed supply of food high in ca lories ha ve turned obesity into a problem a lso a ffecting deve-loping countries. This is a pa ndem ic directly rela ted to a lifestyle tha t is clea rly obesogenic due to the prom otion of environm ents tha t offer increa sed supply of foods high in ca lories, including unhea lthy food a nd la ck of physica l a ctivity.1
Obesity is a predisposing fa ctor for the developm ent a nd exa cerba tion of potentia lly severe disea ses such a s hypertension, insulin resista nce, type 2 dia betes m ellitus, dyslipidem ia , a nd the consequent a therosclerosis a nd m eta bolic syndrom e, with direct im pa ct on m orbidity a nd m orta lity rela ted to these disea ses a nd their effects on ta rget orga ns a nd system s.
Hea lth ca re costs directly rela ted to this condition a nd its influences on a ssocia ted disea ses a ccounted for 9 % of hea lth
expenses in 2 0 0 5 in the USA, tha t is, a bout US$ 1 0 0 billion, a nd the indirect costs for the econom y a re inca lcula bly grea ter.7
All a va ila ble m oda lities of clinica l trea tm ent for weight loss ha ve poor results, with up to 9 5 % recurrence in pa tients with
morbid obesity (BMI ≥ 35 kg/m2 a ssocia ted with com orbidities,
or BMI ≥ 40 kg/m2,). BMI sta nds for body m a ss index, which is
ca lcula ted by the ra tio between the weight in kilogra m s a nd the body surfa ce a rea in m2.8 According to the 1 9 9 1 consensus of the
NIH (U.S. Na tiona l Institute of Hea lth), surgery wa s considered a nd rem a ins a s the only effective trea tm ent for these pa tients who ha ve experienced fa ilure with previous clinica l trea tm ent. In Bra zil, since 2 0 0 0 , the Ministry of Hea lth ha s included the surgica l trea tm ent of m orbid obesity a m ong the procedures covered by the Unified Hea lth System (SUS), esta blishing criteria for its indica tion.9 In 2 0 0 5 a nd 2 0 1 0 , the Federa l Council
of Medicine a lso set sta nda rds for the surgica l trea tm ent of m orbid obesity, a s well a s guidelines for the com position of a m ulti-professiona l tea m to follow up these pa tients in the pre-, intra - a nd postopera tive periods.1 0
Using the different ba ria tric techniques a va ila ble, the surgica l trea tm ent yields good results, with the Roux-en-Y ga stric bypa ss (RYGB) being the surgery m ost often used to trea t m orbid obesity. RYGB shows results with m ore tha n 7 5 % of pa tients losing 5 0 % or m ore excess of body weight, a result tha t is m a inta ined five yea rs a fter the surgery. Beca use of technologica l developm ent a nd a dva nces in a nesthetic a nd postopera tive ca re, m orbidity a nd m orta lity ra tes ha ve grea tly decrea sed a nd currently a re a pproxim a tely 5 % a nd 1 %, respectively.1 1
As a consequence of successful surgica l trea tm ents, there ha s been a n increa se in the num ber of procedures perform ed. While 1 6 ,0 0 0 ba ria tric procedures were ca rried out in the USA in 1 9 9 0 , in 2 0 0 5 , 1 1 3 ,5 0 0 surgeries were perform ed; a n increa se of 7 0 0 %, a nd in 2 0 0 8 the num ber of surgeries wa s a pproxim a tely 2 2 0 ,0 0 0 .1 2
The surgica l trea tm ent of obesity ca n be typica lly divided into three ca tegories: restrictive, m ixed, a nd m a la bsorptive surgeries. Restrictive surgeries ca use ba sic effects origina ted from the restriction in protein a nd ca lorie inta ke; m ixed surgeries a ssocia te food inta ke restriction with the effect of intestina l m a la -bsorption of nutrients; a nd m a la bsorptive surgeries ha ve less or no restriction a nd ca use a grea ter effect on food m a la bsorption by the sm a ll intestine. Beca use of the broa der knowledge tha t ha s been a cquired a bout the role of enteropeptides produced by va rious segm ents of the digestive tra ct in response to the a rriva l of nutrients, this cla ssifica tion certa inly tends to be repla ced by the a da ptive a nd enterohorm ona l role produced by severa l technica l procedures in the m eta bolism a nd control of hunger a nd sa tiety.1 3
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surgica l trea tm ent of obesity with the jejunoilea l bypa ss. The high ra te of com plica tions a ssocia ted with severe m a la bsorp-tion a nd extensive intestina l bypa ss ca used this technique to be a ba ndoned. In the la te 1 9 7 0 s, Scopina ro designed a bilio-pa ncrea tic diversion bybilio-pa ss with sm a ller intestina l diversion a ssocia ted with dista l ga strectom y, a procedure tha t ha s been used until now. An a da pta tion of this technique wa s proposed in the 1 9 8 0 s by Hess a nd Ma rcea u (duodena l switch), which suggested a vertica l ga strectom y, fa shioning a ga stric tube with preserva tion of the pylorus a nd a na stom osis with the dista l segm ent of the sm a ll intestine in the sa m e proportions used in the Scopina ro procedure.
In the 1 9 8 0 s, Ma son proposed the vertica l ba nded ga stro-pla sty a s a restrictive procedure. Such option shows fewer im plica tions for protein, vita m in, a nd tra ce elem ents a bsorption. High recurrence ra tes ha ve ca used this technique to be a lm ost com pletely a ba ndoned, with the suggestion of Roux-en-Y bypa ss ga stropla sty, which consists of a sm a ll ga stric pouch with a volum e ca pa city of between 3 0 a nd 5 0 m l tha t restricts food inta ke. Such pouch m a y or m a y not ha ve em ptying restriction by m ea ns of a ga stric ba nd, a nd it a lso includes a short Roux-en-Y bypa ss, prom oting diversion of the la rgest portion of stom a ch, duodenum , a nd beginning of jejunum from food tra nsit. This m ixed procedure esta blished by Fobi a nd Ca pella , with som e va ria tions, is the surgery m ost often used worldwide a nd pa rti-cula rly in Bra zil, since its introduction by Ga rrido Jr, it ha s been routinely used in severa l ba ria tric surgery centers.1 4
Other procedures a re a lso on the list of ba ria tric procedures currently used. Adjusta ble ga stric ba nding, which is a prim a rily restrictive procedure, wa s developed in the m id-1 9 9 0 a nd consists of a silicone ba nd tha t restricts a sm a ll portion in the ga stric ca rdia , turning the stom a ch into a n hourgla ss, with the ca liber of the ba nd being a djusted through a port in the subcu-ta neous tissue of the a bdom ina l wa ll.
The interest in ba ria tric surgery ha s been increa sing a s this set of trea tm ents becom es a sa fe a nd effective option for trea ting this severe a nd epidem ic disea se a nd new procedures a re suggested. Vertica l ga strectom y ha s been investiga ted with the focus on a specific niche of indica tion, either a s a n initia l procedure in severe ca ses, or a s the technique of choice in borderline ca ses, with lower BMIs or involving extrem e a ge groups, rega rding which there ha s been a n increa sing discussion a bout the extension of surgery recom m enda tion.
In recent yea rs, knowledge a bout th e pa th oph ysiology of obesity a nd other disea ses, like dia betes a nd m eta bolic syndrom e, ha s becom e grea tly broa der pa rtly beca use of the im porta nt contribution from the resea rch in the field of ba ria tric surgery. There ha s been grea t a dva nces a lso in term s of the physiologica l effects of the severa l techniques with cha nges in the neurenteric a xis tha t regula te the m eta bolism m edia ted by intestina l neuropeptides, with im porta nt effects on the regula -tion of hunger a nd sa tiety, glucose m eta bolism , a nd pa ncrea tic
endocrine function. Most surgeries ha ve a lso neurohorm ona l effects in a ddition to those rela ted to restriction a nd/or m a la -bsorption. When the food bolus rea ches certa in regions of the digestive system m ore quickly or fa ils to rea ch them , it gene-ra tes a ca sca de of horm ona l a nd neuropeptide m edia tors, with im porta nt effects on the regula tion of m eta bolic hom eosta sis. The evolution of this knowledge lea ds to im plica tions never im a gined before, such a s the possibility of surgica l trea tm ent of type 2 dia betes, which ha s becom e a current resea rch field ba sed on specific protocols being developed throughout the world.
Of the surgica l pa tients a ged between 1 8 a nd 4 5 , a bout 8 0 % a re wom en. Between 2 0 0 3 a nd 2 0 0 5 , a pproxim a tely 5 0 ,0 0 0 wom en per yea r in this a ge group underwent ba ria tric surgery. As a result of this increa se in the num ber of surgeries, a n increa sing num ber of wom en of reproductive a ge will ha ve a history of ba ria tric surgery.
In a ddition to the im plica tions of the com orbidities listed a bove, p olycys tic ova ry s yndrom e, infertility, ges ta tiona l dia betes, hypertension rela ted to pregna ncy, feta l m a crosom ia , preterm la bor, a bortion, feta l m a lform a tions, a nd juvenile obesity a re a ssocia ted with obesity in wom en of childbea ring a ge.
The weight control a chieved by the surgica l trea tm ent, with the consequent reversion of infertility, a nd the increa sing num ber of wom en of reproductive a ge undergoing surgery lea d to im pli-ca tions rela ted to the ba ria tric surgery a nd the effects of these m eta bolic a nd physiologica l cha nges during pregna ncy.
Despite the fa ct tha t the history of ba ria tric procedures da tes ba ck to the 1 9 6 0 s, there a re few studies a va ila ble a bout the im plica tions of this type of surgery in the pregna ncy a nd gesta tiona l period.
The cha nges in digestive physiology a fter the surgery, which ca n lea d to m a la bsorption of certa in nutrients such a s vita m ins, m inera ls, a nd proteins,1 5 a re responsible for m ost of the concerns
rela ted to pregna ncy a fter undergoing ba ria tric surgery, being a ssocia ted with possible influences on feta l growth a nd nutri-tiona l deficiencies in the fetus a nd pregna nt wom a n.1 6
Postopera tive weight loss occurs m ore ra pidly in the first yea r, a nd the weight usua lly sta bilizes a fter 1 8 m onths. Although few studies ha ve specifica lly eva lua ted this issue, finding no significa nt cha nges between ea rly a nd la te pregna ncies, strict contra ception is genera lly recom m ended for a t lea st one yea r a fter the surgery.1 7
With respect to m a terna l a nd feta l pa ra m eters, Wa x et a l. found no differences in pa tients undergoing RYGB com pa red with controls from the genera l popula tion rega rding the incidence of hypertension, prem a ture rupture of m em bra nes, oligohydra m -nios, a nd delivery a fter 4 1 weeks.1 8
On the other ha nd, com pa ring pregna nt wom en with obese wom en who underwent ba ria tric surgery, Wittgrove et a l.1 7
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m a crosom ia , hypertension, a nd dia betes in opera ted wom en com pa red with the m orbid obese popula tion.
Vita m in deficiencies a re found in pa tients undergoing RYGB, m ost com m only iron deficiency in wom en of childbea ring a ge, ca lcium deficiency, a nd hypovita m inoses A, D a nd B1 2 . There is need of a strict control of possible deficiencies in pregna nt wom en a s the dem a nd for these nutrients increa ses.
In a study published in the current issue, Nom ura et a l. eva lu-a ted the fetlu-a l lu-a nd perinlu-a tlu-a l outcom e of pregnlu-a ncies lu-a fter RYGB, showed the incidence of a nem ia in 8 6 .7 % of the ca ses (Hb < 1 1 m g/dL), with three out of 3 0 pa tients requiring pa rentera l iron repla cem ent a nd receiving blood tra nsfusion. However, these findings did not a ffect feta l well-being or ca used m a jor m a terna l com plica tions. It is im porta nt to em pha size tha t this study eva lu-a ted plu-a tients using lu-a glu-a stric blu-a nd in the RYGB for restriction of ga strojejuna l efflux. Such surgica l procedure is rela ted to higher ra tes of intolera nce to protein, especia lly beef.1 9 Fa intuch et a l.2 0
a lso studied pregna nt popula tion a fter RYGB with ga stric ba nd a nd found decrea ses in hem oglobin a nd iron in the second qua rter of pregna ncy.Anem ia is a result of poor a bsorption of iron a nd coba la m in due to lim ita tions ca used by ga stric a nd duodena l exclusion a nd reduction in iron inta ke prom oted m a inly by the contention ring or very tight a na stom oses. It is found m a inly in wom en of reproductive a ge a s a consequence of chronic weight losses. Som etim es usua l supplem enta tion with ora l m ultivita -m ins is not effective. A recent series of eva lua tion of pa tients a fter RYGB who received da ily ora l supplem enta tion showed preva lence of iron deficiency in 4 0 % of pa tients two yea rs a fter surgery, a nd in 5 4 % of pa tients a fter three yea rs, in whom vita m in B1 2 deficiency occurred in 2 7 %.2 1 Currently, given the
unfa vora ble im pa ct on nutrition, ga stric ba nds ha ve not been used in m a ny ba ria tric surgery centers.
Specific nutritiona l deficiencies, if uncorrected, could lea d to severe feta l im plica tions, such a s growth reta rda tion, m a lform a -tions, a nd feta l dea th.
Regula r la bora tory control is essentia l, a nd correction of deficiencies prior to pregna ncy is a lso crucia l a nd a lwa ys ea sier. All pa tients who underwent surgery receive da ily ora l vita m in supplem enta tion a nd occa siona l pa rentera l supplem enta tion. Identifica tion a nd correction of deficiencies in the pre-pregna ncy period, nutritiona l counseling during pregna ncy, a nd pregna ncy specific vita m in supplem enta tion in a ddition to the supplem enta -tion used in the norm a l postopera tive follow-up period m ost of the tim e a re enough to prevent nutritiona l deficiencies rela ted to RYGB in pregna nt wom en.
In term s of m a la bsorptive surgeries, specia l a ttention should be given to possible protein deficiencies by m ea ns of increa sed protein inta ke a nd m onitoring of the nutritiona l sta tus of pregna nt wom en using supplem enta tion if necessa ry. In other surgeries, this concern is less significa nt, except in ca ses where there is la ck of inta ke of protein foods, such a s in ca ses of RYG with the use of a silicone ring in which there is intolera nce to beef. In
these ca ses, regula r protein supplem enta tion is recom m ended. Hyperem esis gra vida rum m a y a ggra va te these specific situa tions of vita m in a nd m inera l deficiencies, a nd even ca lorie a nd protein deficiencies, a nd should be ca refully m onitored.
There a re few reports in the litera ture up to 2 0 0 9 of interna l hernia s a nd bowel obstructions in pregna ncies a fter ba ria tric surgery a s com plica tions directly rela ted to the surgery. There a re three critica l m om ents when this risk increa ses: in the second qua rter, when the uterus becom es a n a bdom ina l orga n a nd com petes for spa ce with the intestine, a t the end of pregna ncy, when the feta l hea d descends, a nd in the postpa rtum period, when there is uterine involution, periods in which there is exten-sive intra ca vita ry rea rra ngem ent. In a ddition to the m em bra nes a nd a dherences, there a re spa ces where interna l hernia s m a y develop. Ea rly dia gnosis a nd fa st m a na gem ent decrea se the m orbidity of this com plica tion.2 2 Beca use it ha s nonspecific
presenta tion, the suspicion of interna l hernia is a lwa ys m a nda -tory in ca ses of uncha ra cteristic a bdom ina l pa in or intestina l subocclusion episodes. Bilious vom iting ra ises strong suspicion of obstruction dista l to the enteroa na stom osis. A CT sca n with ora l contra st is very sensitive in identifying obstructions, a nd surgery is the m ost a ppropria te m a na gem ent.
In the ca se of a djusta ble ga stric ba nding, ea rly in the gesta -tion, recurrent vom iting ca n lea d to slippa ge of the ba nd a nd subsequent obstruction. As a prophyla ctic m ea sure, com plete em ptying of the ba nd in this initia l period is recom m ended, with subsequent reinsuffla tion during pregna ncy depending on the sym ptom s a nd nutritiona l sta tus of the pa tient a nd fetus, a nd a ga in em ptying the ba nd a t the end of pregna ncy to m inim ize the im pa ct of the restriction during la cta tion.2 3
Ba sed on these da ta , som e preventive m ea sures a re recom -m ended. Postopera tive follow-up, control, recognition a nd ea rly correction of nutritiona l deficiencies, a nd m ultivita m in supplem enta tion, especia lly in wom en of childbea ring a ge using iron supplem enta tion, folic a cid, ca lcium , a nd vita m in B1 2 a re essentia l. As in the usua l postopera tive follow-up of a ll pa tients undergoing surgica l trea tm ent of obesity, in wom en a nd pa rticula rly pregna nt wom en, ca reful m ultidisciplina ry follow-up increa ses the cha nces of success. The postponem ent of pregna ncy to one yea r a fter ba ria tric surgery a lso reduces the possibility of com plica tions.
Therefore, ba ria tric surgery m inim izes the risks a ssocia ted with m orbid obesity, a s well a s the gesta tiona l risks for the wom a n a nd the fetus rela ted to m orbid obesity.
marco aurelio Santo1
daniel riccioppo1
ivan cecconello2
1- Unidade de Cirurgia Bariátrica e Metabólica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP
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