Presentación del tema: "¿ ABORDAJE ANESTESICO DE LA ENFERMEDAD CARDIACA EN LA EMBARAZADA?"— Transcripción de la presentación:
1 ¿ ABORDAJE ANESTESICO DE LA ENFERMEDAD CARDIACA EN LA EMBARAZADA? MARCELINO MURILLO DELUQUEZANESTESIA Y REANIMACIÓNUNIVERSIDAD DE CARTAGENA
2 PREVALENCIA DE LA CARDIOPATIA 1-4%ENFERMEDAD CARDIACA CONGENITAENFERMEDAD REUMATICA CARDIACALa enfermedad cardiaca complica entre 1 % y4 % de los embarazos en los Estados Unidoses la principal causa de morbilidad y mortalidad materna de causa no obstétrica en el ReUnido (1). La enfermedad reumática ha sidoprincipal causa de enfermedad cardiaca en elembarazo en países en vía de desarrollo, perocon el incremento en el cuidado perinatal derecién nacidos con enfermedad cardiaca connita (ECC) y el desarrollo de la cirugía cardiovcular, la ECC es ahora la causa más importade cardiopatía en el embarazo (2,3).Las enfermedades cardiovasculares complicanentre el 0,2 % - 3 % de los embarazos y son unacausa importante de mortalidad materna (1,2).El embarazo y el trabajo de parto son bien tole-rados en pacientes con cardiopatías congénitas(CC), como comunicación interauricular (CIA),comunicación interventricular (CIV), ductusarterioso persistente y anomalía de Ebstein nocomplicadas (3). Esto no ocurre en mujeres conCC cianosantes no corregidas, como el síndromede Eisenmenger y la tetralogía de Fallot (TOF)(4). El Eisenmenger y la hipertensión pulmonarprimaria producen el 50 % de la mortalidad ma-terna por CC (5). La TOF produce el 10 % de lasmuertes, y la mortalidad por estenosis aórticadepende del área valvular funcional. Son signosde mal pronóstico en CC un Hto. > 60 %, SaO2< 80 %, hipertensión ventricular derecha y epi-sodios sincopales (6).La enfermedad cardiaca en el embarazo imponeun riesgo que debe ser evaluado de manera in-terdisciplinaria e instaurar de manera secuencialun protocolo de diagnóstico y manejo basado enla estratificación del riesgo, cuyo objetivo es evitardesenlaces fatales debidos a un manejo no pla-neado. La aplicación de esta aproximación podríaimpactar en una posible reducción de las compli-caciones cardiovasculares asociadas en este gru-po de pacientes. Los aspectos más importantes deesta aproximación se describen a continuación.La implementación de un protoco-lo de estratificación del riesgo de muerte y de laaparición de complicaciones cardiovasculares enla paciente embarazada con cardiopatía le permi-te al anestesiólogo hacer parte integral del grupointerdisciplinario de manejo y, así, tener impactoen la obtención de un mejor resultado materno yperinatal en este grupo de pacientes.
3 CLASE FUNCIONAL MORTALIDAD MATERNA II: 1% III-IV: 5 - 15% MORTALIDAD PERINATALIII-IV : %Maternal outcome seems to correlate best with the functional classification of the patient according to the criteria of the New York Heart Association (NYHA) (
4 ESTRATIFICACIÓN DEL RIESGO CLARK ET ALSeveridad anatómica de la lesiónEstenosis aortica severaHTPEnfermedad aorticaMortalidad 50%Eventos cardiacos previos?La implementación de un protoco-lo de estratificación del riesgo de muerte y de laaparición de complicaciones cardiovasculares enla paciente embarazada con cardiopatía le permi-te al anestesiólogo hacer parte integral del grupointerdisciplinario de manejo y, así, tener impactoen la obtención de un mejor resultado materno yperinatal en este grupo de pacientes.HCTO > 60%Sat O ₂ < 80 %HIPERTESIÓN VENTRICULAR DERECHASINCOPEMaternal outcome seems to correlate best with the functional classification of the patient according to the criteria of the New York Heart Association (NYHA) ( Box 40-1 ). Exceptions include patients with pulmonary hypertension, significant left ventricular dysfunction, and severe cases of Marfan syndrome (especially those women with significant enlargement of the aortic root). These lesions pose a very high risk and may contraindicate pregnancy, regardless of functional class. Otherwise, class I or II patients have a maternal mortality rate of less than 1%, whereas class III or IV patients have a mortality rate between 5% and 15%. Perinatal loss also is associated with maternal functional class; patients who are class III or IV have a perinatal mortality rate between 20% and 30%.  
5 ESTRATIFICACIÓN DEL RIESGO 2001 se publico el estudiio tipo…., con 562 preg reclutadas, ya que hasta el momento no se habia definido adecuadamente el riesgo de morbimortalidad en el embarazo y neonatos asociado con el embarazo.El estudio CARPREG de siu et al, encontraron que eventos cardiacos previos predicen de forma independiente la ocurrencia de eventos maternos usando un indice de riesgoOjo eventos cardiacos previos como:arrhythmia, poor functional class or cyanosis, left heartobstruction, and left ventricular systolic dysfunction son los factores independients de riesgoEl 20% de neonatos que se complicaron estaban asociados a pobre clase funcional, cianosis, obstruccion ventricular izquierda, cigarrillo, embarazos multiples, anticoagulacionEstudio canadience busco validar el indice de reisgo.Estudio con 562 mujeres en 13 hostpitalesClark y colaboradores (6), define la severidadanatómica de las lesiones como el único modo deestratificación; es decir, pacientes con estenosisaórtica severa, hipertensión pulmonar de cual-quier etiología y enfermedad de la aorta, comolas lesiones con mayor mortalidad (50 %). El pro-blema de esta clasificación es que sólo tiene encuenta la lesión sin darles importancia a los datosclínicos o los eventos cardiacos previos. El índicede riesgo desarrollado por el estudio canadien-se, conocido como CARPREG (7,8), fue publicadocon el fin de predecir complicaciones cardiacasrelacionadas con el embarazo en pacientes concardiopatías, teniendo en cuenta no sólo la lesiónanatómica, sino los datos del estado clínico.
6 ESTRATIFICACIÓN DEL RIESGO ESTUDIO CARPREGPREDICE COMPLICACIONES CARDIACASCOMBINA:LESION ANATOMICADATOS DEL ESTADO CLINICO
7 ¿PREDICTORES DE EVENTOS CARDIO-VASCULARES? NYHA III-IV O CIANOSISANTECED: ARRITMIA O EVENTO CARDIACOVM: <2CMVA: < 1.5 CMGRADIENTE VI > 30 mmHgDISFUNCIÓN VI - FE < 40%
9 INDICE DE RIESGO REVISADO No. De predictoresRiesgo Estimado5%127%>175
10 ¿QUÉ EVENTOS CARDIO-VASCULARES SE PRESENTARON? EVENTOS CARDIACOS13%55% PREPARTOEDEMA PULMONARNYHA III : 19%ARRITMIAS 4.7%INFARTOPCR 1% (6)MUERTEPara el desarrollo de eventos cardiacos, comoedema pulmonar, arritmias, enfermedad cere-brovascular, paro de origen cardiaco y muerte,se identificaron cuatro predictores:
12 GUIAS DE LA ACC-AHA - ESC Estenosis Aórtica severa con o sin síntomas.Estenosis Mitral sintomáticaNYHA II-IVInsuficiencia Aórtica o Mitral con NYHA III o IVEnfermedad valvular Aortica o Mitral con FE < 40%, o HTP > 75 mmHgSíndrome Marfan con o sin IAVálvula protésica mecánica requiere anticoagulaciónEl Colegio Americano de Cardiología-AsociaciónAmericana del Corazón (ACC/AHA, por sus si-glas en inglés), en el 2006, y la Sociedad Euro-pea de Cardiología (ESC), en el 2007, publicaronlas guías para enfermedad cardiaca valvular, enlas que consideran que son de alto riesgo mater-no y fetal durante el embarazo las mujeres conuna de las siguientes lesiones (9,10):• Estenosis aórtica severa con o sin síntomas.• Estenosis mitral sintomática (NYHA II a IV).• Insuficiencia aórtica o mitral con NYHA III o IV.• Enfermedad valvular aórtica o mitral condisfunción ventricular izquierda severa (defi-nida como fracción de eyección < 40%) o se-vera hipertensión pulmonar (presión arterialsistólica arteria pulmonar > 75 mmHg).• Síndrome de Marfán con o sin insuficienciaaórtica (11).Válvula protésica mecánica que requiere an-ticoagulación.
13 ESTUDIO EUROPEO RETROSPECTIVO DESDE 1980 A 2007, NOMBRE ZAHARA, In 1802 women with CHD, 1302 completed pregnancies were observed. Independent predictors of cardiac, obstetric,and neonatal complications were calculated using logistic regression. The most prevalent cardiac complications duringpregnancy were arrhythmias (4.7%) and heart failure (1.6%). Factors independently associated with maternal cardiaccomplications were the presence of cyanotic heart disease (corrected/uncorrected) (P , ), the use of cardiacmedication before pregnancy (P , ), and left heart obstruction (P , ). New characteristics weremechan-ical valve replacement (P ¼ ), and systemic (P ¼ 0.04) or pulmonary atrioventricular valve regurgitation relatedwith the underlying (moderately) complexCHD(P ¼ 0.03). Anewrisk score for cardiac complications is proposed. Themost prevalent obstetric complications were hypertensive complications (12.2%). No correlation of maternal charac-teristics with adverse obstetric outcome was found. The most prevalent neonatal complications were premature birthLimitations of the score for patientswith CHD are that it is developed based on a cohort that includedpatients with primary electrical disease as well as acquired heartdisease. Moreover, several types of (mainly complex) CHD wereunderrepresented.2,3It is suggested that the CARPREG cardiacrisk score therefore needs to be modiﬁed to assess the risk ofpregnancy in women with CHDMethodsFor the present ZAHARA study, female patients with CHD aged 18–58 years enrolled in the nation-wide CONgenital CORvitia(CONCOR) registry and a Belgian63% NULIPARASCOMPLICACION CARDIACA MAYOR: ARRITMIA Y FALLA CARDIACADE LAS COMPLICACIONES OBSTETRICAS HTACOMPLICACION NEONATAL: PEQUEÑO PARA EDAD GESTACIONAL Y PARTO PREMATURO
14 ESTUDIO ZAHARA NUEVOS FACTORES IND. CONFIRMA: INSUFICIENCIA VALVULAR ENF CIANOSANTE CORREGIDA O NOPROTESIS VALVULARESCONFIRMA:HISTORIA DE ARRITMIANYHAOBSTRUCCIÓN TRACTO SALIDAUSO DE MEDICAMENTOSESTUDIO EUROPEO RETROSPECTIVO DESDE 1980 A 2007, NOMBRE ZAHARA,In 1802 women with CHD, 1302 completed pregnancies were observed. Independent predictors of cardiac, obstetric,and neonatal complications were calculated using logistic regression. The most prevalent cardiac complications duringpregnancy were arrhythmias (4.7%) and heart failure (1.6%). Factors independently associated with maternal cardiaccomplications were the presence of cyanotic heart disease (corrected/uncorrected) (P , ), the use of cardiacmedication before pregnancy (P , ), and left heart obstruction (P , ). New characteristics weremechan-ical valve replacement (P ¼ ), and systemic (P ¼ 0.04) or pulmonary atrioventricular valve regurgitation relatedwith the underlying (moderately) complexCHD(P ¼ 0.03). Anewrisk score for cardiac complications is proposed. Themost prevalent obstetric complications were hypertensive complications (12.2%). No correlation of maternal charac-teristics with adverse obstetric outcome was found. The most prevalent neonatal complications were premature birthLimitations of the score for patientswith CHD are that it is developed based on a cohort that includedpatients with primary electrical disease as well as acquired heartdisease. Moreover, several types of (mainly complex) CHD wereunderrepresented.2,3It is suggested that the CARPREG cardiacrisk score therefore needs to be modiﬁed to assess the risk ofpregnancy in women with CHDMethodsFor the present ZAHARA study, female patients with CHD aged 18–58 years enrolled in the nation-wide CONgenital CORvitia(CONCOR) registry and a Belgian63% NULIPARASCOMPLICACION CARDIACA MAYOR: ARRITMIA Y FALLA CARDIACADE LAS COMPLICACIONES OBSTETRICAS HTACOMPLICACION NEONATAL: PEQUEÑO PARA EDAD GESTACIONAL Y PARTO PREMATURO
16 MODELO MULTIVARIABLE: COMPLICACIONES CARDIACAS CORREGIDAS POR EDAD Y PARIDAD MATERNA OR (IC 95%)VALOR DE PHistoria de arritmias4.3 (1.8–10.2)0.0011Medicamentos cardiacos previos4.2 (2.1–8.6)<0.0001NYHA Clase funcional2.2 (1.1–4.5)0.0298Gradiente AV >50, AVA 1.0 cm212.9 (3.9–42.3)Insuficiencia Aortica moderada/severa2.0 (1.0–4.0)0.0427Insuficiencia pulmonar mode/severa2.3 (1.1–5.0)0.0287Válvula proteica mecánica74.7 (5.3–1057)0.0014Enf ermedad cardiaca cianosante3.0 (1.7–5.0)In concordance with the CARPREG and other investigators, weentiﬁed NYHA functional class .II, left heart obstructive lesions,nd a history of arrhythmias to be independent predictors ofmaternalardiac complications.20,21It needs to be added that arrhythmiaswerehe most common cardiac complication in women with a history ofrrhythmias. Silversides et al.22reported earlier that in women withre-existing cardiac rhythm disorders, exacerbation of arrhythmicpisodes during pregnancy was common.In contrast to the CARPREG report, a decreased systemicentricular function was a univariate but not multivariate predictorcardiac complications. In this retrospective study, we had to useless accurate deﬁnition for decreased left ventricular functionubjective mostly echocardiographic estimation vs. measurementejection fraction in the CARPREG study) which may in partxplain this difference. The association between signiﬁcant sys-mic AV valve regurgitation and decreased systemic ventricularnction (e.g. in patients with a systemic right ventricle) may benother part of the explanation, as systemic AV valve regurgitationmerged as an independently associated characteristic in our study.yanosis and a history of cardiac complications also did not corre-te with adverse cardiac outcome. The low incidence of theseriables may at least be in part the explanation. Cyanoticomen are often advised against pregnancy.23
17 MODELO MULTIVARIABLE: COMPLICACIONES NEONATALES CORREGIDAS POR EDAD Y PARIDAD MATERNA OR (IC 95%)VALOR DE PGemelar o múltiple5.4 (1.9–15.2)0.0014Tabaquismo en embarazo1.7 (1.2–2.4)0.0070Enf cardaiaca cianosante2.0 (1.4–2.9)0.0003Valvula protesica mecánica13.9 (1.2–157)0.0331Medicación cardíaca2.2 (1.4–3.5)0.0009
19 Risk scoresThe CARPREG risk score performed inadequately in our popu-27,28reports.lation and largely overestimated risk, in line with otherThe differences between the populations that weincidence of cardiac complications appears relatively low (7.6%)CARPREG cardiac risk score in our population. In addition, thepointed out may in part explain the poor performance of thein comparison to 13 and 19.4% reported by Siu et al.Khairy et al.and2,3,29However, the cardiac complication rate in the4at higher risk. The cohort investigated by Khairy et al. had an over-cies). Apparently, acquired or arrhythmic heart disease patients areCARPREG study in patients with CHD is 7.1% (32 in 445 pregnan-representation of complex CHD, which may explain the higherthat we needed to use in this retrospective study could also inheart failure (therapeutic interventions had to be performed)cardiac complication rate. Nonetheless, the different deﬁnition ofcations in our study, however, is comparable to the frequencypart explain this discrepancy. The incidence of cardiac compli-The modiﬁcation1found in a recently published literature review.of the risk index (as explained in the Results section) seems toThe representation of risk factors in the population determinesscores have signiﬁcant limitations restricting indiscriminative use.enhance discrimination and calibration. Importantly, both riskary arterial hypertension are likely to be underrepresented in con-which risk factors emerge. Important risk factors such as pulmon-lation of risk scores should be only a part of pre-pregnancy riskidentiﬁed. Therefore, it is important to underline that the calcu-temporaneous cohorts, preventing such risk factors to beassessment. We advocate a pre-pregnancy evaluation in an outpa-expert in the ﬁeld. In addition to weighing predictors found inand an echocardiography according to a predeﬁned protocol by antient setting, including physical examination, laboratory evaluation,ZAHARA and CARPREG and calculating risk scores, disease-risk calculation. Also existing guidelines and expert articlespregnancy risk in order to avoid over-simpliﬁcation implied byspeciﬁc information should always be used when estimatingshould be consulted.score in a large prospective study remains necessary, before useExternal validation of our modiﬁed risk30Limitationsin everyday practice is possible.lacks a historical ‘matching’ control population. This is, however,rospective design. First and most importantly, the present studyMost of the limitations of the present study are related to the ret-not as straightforward and simple exercise, as the vast majoritygynaecological hospital care are a selected population with (mainlyhome with the help of a midwife. Therefore, the women consultingof healthy women in the Netherlands and Belgium deliver atcomplications. Moreover, the concept of a control population is,obstetric or neonatal) complications or at higher risk for thesefore, a prospective study would be the best option, on the otherin an identical fashion according to a predeﬁned protocol. There-in our opinion, only sustainable, when both cohorts are followedhand, to collect the number of pregnancies provided in theation is the possibility of underreporting. Because data-retrievalinterfere with the contemporaneous applicability. A second limit-present study; data collection would take at least 10 years andeducated personnel) were included. Third, we need to take intowas retrospective, only documented complications (by medicallyaccount that for the present study, a survivor cohort was selected
21 Blood lossBleeding may result from impaired coagulation resultingfrom anticoagulant therapy or associated with polycy-thaemia, or from uterine atony secondary to withholdingof oxytocic drugs (see below). There are also obstetriccauses of bleeding such as cervical or vaginal tears, orbleeding associated with operative delivery.Blood loss is particularly important in patients withcardiac disease for two reasons. First, they may have areduced capacity to compensate for hypovolaemia, forexample if cardiac output is relatively fixed, as in aorticstenosis, or dependent on venous return, as in the Fontancirculation. Compensatory increases in heart rate may beobtunded by drugs such as b blockers, or prevented bycardiac conduction abnormalities. Second, overzealousinfusion of intravenous fluid can result in pulmonary oe-dema (see below). For these reasons, it is vital to ensureboth adequate monitoring and management of labourand delivery, and prompt recognition and treatment ofhaemorrhage. Delivery in such cases is not routine andshould be performed by the most experienced staffavailable.
22 CONTROL PERIPARTO Sangrado Edema Pulmonar Arritmias Sd de Hipotensión AortocavaEmbolismoEndocarditis Bacteriana.Bleeding may result from impaired coagulation resultingBlood lossfrom anticoagulant therapy or associated with polycy-thaemia, or from uterine atony secondary to withholdingof oxytocic drugs (see below). There are also obstetricbleeding associated with operative delivery.causes of bleeding such as cervical or vaginal tears, orBlood loss is particularly important in patients withcardiac disease for two reasons. First, they may have areduced capacity to compensate for hypovolaemia, forstenosis, or dependent on venous return, as in the Fontanexample if cardiac output is relatively fixed, as in aorticOxytocicsThe cardiovascular side effects of standard doses of oxy-tocin have been known for 30 years (decreased meantance by 50%; increased cardiac output by 50% andarterial pressure by 30% and systemic vascular resis-heart rate and stroke volume by 20-30%10), but theirpotentially deleterious consequences in women with car-recently.diac disease have been less widely acknowledged until2,11The highlighting of this danger in a recentReport on Confidential Enquiries into Maternal Deaths12has led to a dramatic change in practice.However, thiscreates a dilemma since withholding oxytocin may leadto haemorrhage, which may also be dangerous in thesethough, and these are presented in Table 5.patients (see above). A number of options remain,Pulmonary oedemaPulmonary oedema may result from a combination offluid retention associated with pregnancy, shifts betweenfailure and/or preeclampsia, and excessive intravenousfluid compartments around the time of delivery, heartfluids. During a long labour, the total volume of paren-teral fluids given can easily mount up when intravenousdrugs such as antibiotics and oxytocin are included indruple-strength solutions should be used and carefulthe count. In women with severe disease, double- or qua-hourly calculations made of fluid balance. During cae-sarean section, when fluid shifts are more dramatic,we often favour giving a 5-mg dose of furosemide atsion of blood from the contracting uterus, although wethe time of delivery to counter the effect of autotransfu-are aware that this practice is not evidence-based.ArrhythmiasAll pregnant women are prone to tachycardia andthese may impair cardiac filling and output, and coro-arrhythmias; in women with pre-existing cardiac diseasenary perfusion. Drugs that are known to cause tachycar-dia (such as oxytocin [see above] and ephedrine) shouldbe avoided if possible. If vasoconstrictors are indicatedour drug of choice. If arrhythmias occur, the treatmentin regional anaesthesia, phenylephrine has always beenoptions are influenced by the underlying lesion, experience with any previous drugs in that patient, thecloseness of delivery and the degree of cardiovascularcompromise. The risk of aortocaval compression andpaired or DC cardioversion is required) should alwaysaspiration of gastric contents (if consciousness is im-be borne in mind.Reduced systemic vascular resistanceA decrease in SVR may be dangerous in cardiac diseasemay be profound, and for which the compromised car-for two reasons. First, it may lead to hypotension thatdiovascular system is unable to compensate. This isespecially likely if the cardiac output is fixed, for exam-ple with left-sided stenotic/obstructive lesions. Second,a shunt (or the potential for such a shunt) exists, reduc-reduced SVR may increase right-to-left shunting if suching pulmonary blood flow further. This can lead to a spiral of worsening hypoxaemia, leading to pulmonaryvasoconstriction and yet further hypoxaemia, withpotentially disastrous results. Drugs that cause vasodila-possible; traditionally the same has been said for regio-tation (such as oxytocin; see above) should be avoided ifnal techniques,13although there is now extensive expe-be used safely in such conditions.rience suggesting that spinal and epidural techniques can14–16Acute pulmonary hypertensionSudden increases in pulmonary arterial pressure (pul-monary hypertensive crisis) may lead to right ventricularand catastrophic. The danger is well recognised infailure and ischaemia; furthermore, this may be suddenknown cases of severe primary or secondary pulmonaryhypertension, but more recently the possibility of suchcrises has been suggested in relatively mild disease. Embolismoping thrombosis, and embolism may occur peripartum.Women with cardiac disease are at greater risk of devel-A particular risk in women with a right-to-left shunt (orthe potential for one) is a systemic embolus, whichbypasses the lungs and causes ischaemia or infarction inmen are also at risk from air embolism; thus a smallvital organs such as the heart, brain or kidney. Such wo-amount of air thatmight ordinarily be filtered by the lungscan cause catastrophic systemic effects such as stroke ormyocardial infarction. Obsessional care must thereforeBacterial endocarditisbe taken to exclude air from all intravenous lines.It is easy to overlook simple antibiotic prophylaxis amidstthe complexity of congenital heart disease. It is importantto ensure that prophylactic antibiotics such as amoxycil-Management of deliverylin and gentamicin are given, using standard regimens.The overall aim is to reduce the stress on the mother andher heart, whilst of course maintaining cardiac output,and placental and fetal circulation. To do this the motherdisruption to her cardiovascular system. This can berequires effective pain relief and the minimum possibleachieved first, by close clinical monitoring, second, byavoiding sudden changes whenever possible and takingcare to introduce interventions such as regional anaes-complications that may supervene, in particular pre-thesia gradually and third, by close attention to obstetriceclampsia and haemorrhage. Good communication andpatience are required on the part of all members of theteam, and the obstetricians must give the anaesthetistcompression must be avoided at all times.plenty of notice if intervention is required. AortocavalIn contrast to traditional obstetric managementwhereby mothers with cardiac disease would routinelyundergo elective caesarean section,the approach taken17in our unit is one of minimal surgical intervention when-ever possible in order to avoid complications such asinfection, bleeding, deep vein thrombosis and instability18,19associated with anaesthesia.MonitoringPulse oximetry and electrocardiography should be con-sidered for all but the mildest cases even though thetry is vital in cyanotic heart disease as an indicator of themother may find the extra wires intrusive. Pulse oxime-degree of shunting, while in cases at risk of developingpulmonary oedema it may detect the early stages beforeclinical features are apparent.invasive monitoring depending on the nature and sever-In general, we have developed an escalating scale fority of the underlying condition, the severity of symp-toms, and the likelihood for obstetric intervention orcomplications. Conditions associated with a higher riskimpairment and/or the mothers symptoms are severe,of mortality (Table 1), or those in which the degree ofwould routinely receive invasive arterial monitoring,as would those who develop preeclampsia or are thoughtto be at high risk of bleeding. In such situations, thealerting staff to problems and guiding vasoconstrictorbeat-by-beat information provided is invaluable foror inotropic therapy. Contrary to the experience of someothers, we have found the management of arterial lineson the labour ward to pose few practical problems ifthetic and technical staff.the midwifery staff are adequately supported by anaes-We place central venous lines less often, and thispractice reflects that in other units in the UK.15,16vasoactive drugs, and to allow central venous monitoringCentral venous lines are particularly useful for infusingin patients at risk from fluid overload, such as thosealready with cardiac failure, or those especially sensitiveto hypovolaemia, such as those with valve stenosis.measured in complex cardiac disease, and central linesHowever, it is not always clear what is actually beingare not without risk. Furthermore, mothers in late preg-nancy, especially those with cardiac disease, find it diffi-cult to lie flat, let alone head-down, and the increased softlation difficult. When a central line is deemed necessary,tissues and fluid retention of pregnancy may make cannu-we usually favour peripheral access, via the antecubitalfossa, if possible. The same caveats apply to the use ofpulmonary artery catheters, though their complicationsmore dangerous. For this reason, even though pulmonary(arrhythmias, pulmonary artery rupture) may be evenartery catheters may provide indirect information relatingto the left ventricle and allow a route for infusing drugsinto the pulmonary circulation,we rarely place them.20Transeosophageal echocardiography,21Doppler car-diography and other tools for measuring cardiac output
23 MONITORIA PULSO-OXIMETRIA LINEA ARTERIAL CVC ECO TRANSTRAQUEAL BIOMARCADORESMonitoringmother may find the extra wires intrusive. Pulse oxime-sidered for all but the mildest cases even though thePulse oximetry and electrocardiography should be con-try is vital in cyanotic heart disease as an indicator of theclinical features are apparent.pulmonary oedema it may detect the early stages beforedegree of shunting, while in cases at risk of developingity of the underlying condition, the severity of symp-invasive monitoring depending on the nature and sever-In general, we have developed an escalating scale fortoms, and the likelihood for obstetric intervention orimpairment and/or the mothers symptoms are severe,of mortality (Table 1), or those in which the degree ofcomplications. Conditions associated with a higher riskto be at high risk of bleeding. In such situations, theas would those who develop preeclampsia or are thoughtwould routinely receive invasive arterial monitoring,beat-by-beat information provided is invaluable forothers, we have found the management of arterial linesor inotropic therapy. Contrary to the experience of somealerting staff to problems and guiding vasoconstrictorthetic and technical staff.the midwifery staff are adequately supported by anaes-on the labour ward to pose few practical problems ifWe place central venous lines less often, and thisCentral venous lines are particularly useful for infusing15,16practice reflects that in other units in the UK.already with cardiac failure, or those especially sensitivein patients at risk from fluid overload, such as thosevasoactive drugs, and to allow central venous monitoringto hypovolaemia, such as those with valve stenosis.are not without risk. Furthermore, mothers in late preg-measured in complex cardiac disease, and central linesHowever, it is not always clear what is actually beingtissues and fluid retention of pregnancy may make cannu-cult to lie flat, let alone head-down, and the increased softnancy, especially those with cardiac disease, find it diffi-lation difficult. When a central line is deemed necessary,pulmonary artery catheters, though their complicationsfossa, if possible. The same caveats apply to the use ofwe usually favour peripheral access, via the antecubitalartery catheters may provide indirect information relatingmore dangerous. For this reason, even though pulmonary(arrhythmias, pulmonary artery rupture) may be evento the left ventricle and allow a route for infusing drugswe rarely place them.20into the pulmonary circulation,Doppler car-21Transeosophageal echocardiography,diography and other tools for measuring cardiac outputcially during caesarean section when there is little roombut their place is uncertain, espe-have been described22Labour and vaginal deliveryawake and unable to tolerate an oesophageal probe.or time for bulky equipment, and the patient may beWe would now recommend low-dose epidural analgesiaanticoagulation, although the advantage of regionallabour, an exception being those receiving therapeuticfor virtually all women with cardiac disease undertakingSolutions containing bupivacaine 60.1% with fentanylepidural haematoma when prophylactic heparin is used.analgesia usually outweighs the relatively small risk of2-5 lg/mL provide good cardiostability, even in thoseand we have found no19,23with fixed output states,scribed, either as a single injection or as the initialthecal opioids without local anaesthetic have been de-advantage of infusions over boluses of 5-15 mL. Intra-part of a combined epidural-spinal or continuous spinalalthough we have no experience of this21,23technique,pital in the third trimester, there is usually plenty of timewomen with severe disease are usually admitted to hos-ourselves, finding the epidural regimen adequate. Sinceto site the epidural either in early labour or before labourwomen undergoing labour are, first: appropriate moni-its siting. Two key features of the management plan foris induced, so that they are in minimal discomfort duringeffects of the Valsalva manoeuvre.lowed in the second stage in order to limit or avoid thetoring (see above) and second: limited or no pushing al-Caesarean sectionand it is our belief that it is the care with which eachscribed for caesarean section in most cardiac conditionsBoth regional and general anaesthesia have been de-enced by a number of factors:is most important. The choice of technique can be influ-technique is used, rather than the technique itself, that(i) The likelihood of complications and the appropri-which is more easily administered during generalof arrhythmias may require DC cardioversion,ate treatment, for example: those with a high riskinduced by regional anaesthesia, compared with(ii) The risk from a potentially severe drop in SVRanaesthesia.the risk from the negative inotropic effects of gen-for example, a drop in SVR may cause a cata-syndrome and a large ventricular septal defect,eral anaesthesia. In a patient with Eisenmengerserations, depending on the particular case. Thisalthough this may be outweighed by other consid-strophic reduction in pulmonary blood flow,On the other hand, carefully controlled regionalmight favour general anaesthesia in certain cases.
24 VÍA DEL PARTO Analgesia para el trabajo de parto Parto vaginal excepto:Aortopatía con raiz aortica > 4 cmsDisección aórticaAneurisma de aorta toráxicaProtesis mecánica y anticoagulación warfarinaHipertesión pulmonar severaVía del partoLa vía del parto debe ser decidida por las con-diciones obstétricas; en general, está permitidoel parto vaginal. En nuestro reporte, el 60 % delas pacientes terminaron su embarazo por par-to vaginal, todas bajo analgesia conductiva. Lasúnicas indicaciones de cesárea por causa car-diaca son: la aortopatía con raíz aórtica > 4 cm ocrecimiento progresivo de ésta, disección aórticao aneurisma de aorta torácica y anticoagulacióncon warfarina en las pacientes con prótesis val-vulares mecánicas, por el riesgo de hemorragiaintraventricular cerebral en el feto (6).Los grandes centros de referencia de enferme-dades cardiacas en el embarazo (17) están re-comendando recientemente la posibilidad decesárea programada en pacientes con enferme-dad cardiaca con muy alto riesgo de muerte o dedesarrollo de complicaciones cardiovascularesgraves, como en el caso de pacientes con hiper-tensión pulmonar severa de cualquier etiología,debido a la posibilidad de realizar el proceso determinación del embarazo en un ambiente “con-trolado”, que permita evitar complicaciones rela-cionadas con la presencia de personal no fami-liarizado con la patología o la falta de recursosen escenarios no planeados, principalmente, fi-nes de semana y turnos nocturnos.
25 TÉCNICA ANESTÉSICA METAS HEMODINAMICAS TECNICA ESPINAL CONTINUA TECNICA COMBINADAANESTESIA GENERALNo existe en este momento en la literatura la po-sibilidad de definir si la mortalidad de este grupode pacientes está influenciada por la elección deuna técnica anestésica en particular. Los gruposde anestesia obstétrica se inclinan, recientemente,por el uso de técnicas conductivas (18). En nuestroreporte, las pacientes de riesgo alto, como tetralo-gía de Fallot, y las pacientes con CMP que teníandisfunción ventricular severa fueron manejadascon anestesia general; el resto, con técnicas con-ductivas basadas en lo que denominamos “metashemodinámicas”. Es decir, mantener normovole-mia e incremento en las resistencias vasculares enpacientes catalogadas como de alto riesgo.La aplicación de técnicas conductivas que per-mitan la titulación del grado anestésico deseadohan sido descritas en el caso de pacientes con le-siones estenóticas severas del corazón izquierdo,como estenosis aórtica severa (19) o lesiones aso-ciadas con hipertensión pulmonar severa (20), locual reporta seguridad con su utilización.Both regional and general anaesthesia have been de-scribed for caesarean section in most cardiac conditionsand it is our belief that it is the care with which eachtechnique is used, rather than the technique itself, thatis most important. The choice of technique can be influ-enced by a number of factors:(i) The likelihood of complications and the appropri-ate treatment, for example: those with a high riskof arrhythmias may require DC cardioversion,which is more easily administered during generalanaesthesia.(ii) The risk from a potentially severe drop in SVRinduced by regional anaesthesia, compared withthe risk from the negative inotropic effects of gen-eral anaesthesia. In a patient with Eisenmengerssyndrome and a large ventricular septal defect,for example, a drop in SVR may cause a cata-strophic reduction in pulmonary blood flow,although this may be outweighed by other consid-erations, depending on the particular case. Thismight favour general anaesthesia in certain cases.On the other hand, carefully controlled regionalanaesthesia may preserve cardiac function and bepreferable in cases where there is markedlyimpaired cardiac contractility.The presence of pulmonary hypertension. The riskof precipitating an acute pulmonary hypertensivecrisis due to tracheal intubation, inadequate neuro-muscular blockade, coughing, etc, must beweighed against the ability, with general anaesthe-sia, both to give 100% oxygen and to avoid therisk of a poor regional block.The potential risk of thromboembolism and theneed for prophylactic or therapeutic anticoagula-tion, and issues around the timing of the latter.The likelihood of maternal death and the mothersattitude. If the outlook for either the mother or thefetus is very poor she may be desperate to see andhold her baby at least once, during the operation,favouring regional anaesthesia. On the other hand,if for example she experiences severe cyanoticand/or pulmonary hypertensive crises when anx-ious, it might be better to avoid this stress intra-operatively by electing for general anaesthesia.The likely need for postoperative controlled venti-lation and/or further invasive treatment, includingcardiac procedures.(vii) The likelihood for prolonged/complicated surgery,for example, if there are associated intra-abdomi-nal congenital abnormalities.(ix) The presence of any associated abnormalitiesaffecting the airway.(x) The anaesthetists preference.The overall approach is as we have already discussedabove. The aim is for gradual, careful introduction ofgeneral or regional anaesthesia, with close attention tothe problems already considered and prompt interven-tion should the need arise. If emergency caesarean sec-tion is required, we aim to extend a pre-existingregional block if time permits and if not, consider gen-eral anaesthesia. The choice of drugs for the latter isthe same as for non-pregnant cases and depends on theanaesthetists preference and the physical status of themother, the effects on the fetus being a secondary issue.POSTPARTUMAll the problems highlighted above may also occur afterdelivery. This is a particularly important time since thereis a tendency for congratulation and distraction awayfrom the close attention that these mothers require. Care-ful monitoring in an appropriately staffed area able toprovide high dependency care is vital. Fluid balance isa particular area of concern, especially if there isongoing bleeding, perhaps as a result of withholding oxy-tocin. The possibility of coincidental preeclampsia or other obstetric complications must also be remembered.Falling oxygen saturation may indicate worsening shuntor pulmonary oedema as well as the usual causes such asatelectasis, aspiration, etc. Adequate postoperative anal-gesia is important; neuraxial opioids are particularly use-ful. Prophylaxis against deep vein thrombosis should be(re)started and care taken to detect and treat genital tractor wound infection early. How long close observation isrequired is uncertain; we have developed an approachthat errs on the side of caution, depending on the lesionand coloured by our own experience of complicationsthat may occur several days after delivery. In Eisenm-engers syndrome, for example, sudden death typicallyoccurs 1-2 weeks after delivery, possibly from multiplepulmonary embolism, pulmonary haemorrhage, or both.
27 Y POST PARTO QUE? MUERTE SUBITA 1-2 SEMANAS DESPUES. EMBOLISMO PULMONARHEMORRAGIA PULMONAR
28 CUIDADOS ESPECIALES SHUNTS IZQ-DER COARTACION AORTICA BURBUJAS DE AIRE PERIDURALEMBOLISMO PARADOJICOCONTROL DEL DOLOROXIGENOCOARTACION AORTICAMONITORIZAR GRADIENTEDISECCIÓNHEREDITARIOMORTALIDAD FETALMONITORIA INVASIVALeft-to-Right ShuntsLesions such as a small atrial septal defect (ASD), ventricular septal defect (VSD), or patent ductus arteriosus (PDA) may produce a modest degree of left-to-right intracardiac shunting, which often is well tolerated during pregnancy. Anesthetic management of patients with these defects should include attention to the following details. First, care should be taken to avoid the accidental intravenous infusion of air bubbles. Second, if epidural anesthesia is used, the anesthesiologist should use a loss-of-resistance to saline rather than air to identify the epidural space. Epidural injection of even small amounts of air can result in systemic embolization. Transient reversals of atrial pressure gradients during the cardiac cycle may allow paradoxical air emboli to occur, even when mean right atrial pressure is lower than mean left atrial pressure. Third, early administration of epidural anesthesia is desirable. Pain causes increased maternal concentrations of catecholamines and increased maternal SVR and may increase the severity of left-to-right shunt resulting in pulmonary hypertension and right ventricular failure. Early administration of epidural anesthesia allows a pain-free labor and prevents the increased maternal concentrations of catecholamines and increased maternal SVR. Fourth, a slow onset of epidural anesthesia is preferred. A rapid decrease in SVR could result in a reversal of shunt flow, and an asymptomatic left-to-right shunt may become a right-to-left shunt with maternal hypoxemia. Finally, the patient should receive supplemental oxygen, and it seems prudent to monitor hemoglobin oxygen saturation. Even mild hypoxemia can result in increased pulmonary vascular resistance and reversal of shunt flow. It also is important to avoid hypercarbia and acidosis, which may increase pulmonary vascular resistance.Coarctation of the AortaCoarctation of the aorta is a congenital lesion that is more common in males than in females. Patients who have undergone successful corrective surgery and who have normal arm and leg blood pressures do not require special precautions or monitoring. An arm-to-leg gradient of less than 20 mm Hg is associated with a good outcome of pregnancy. Pregnant women with uncorrected coarctation or a residual decrease in aortic diameter are at high risk for left ventricular failure, aortic rupture or dissection, and endocarditis. In such pregnancies the fetal mortality rate may approach 20% because of decreased uterine perfusion distal to the aortic lesion. The incidence of congenital heart disease is approximately 3% in the offspring of mothers with aortic coarctation. Compared with the general population, patients with aortic coarctation are more likely to have a bicuspid aortic valve (hence the increased risk of endocarditis) or an aneurysm in the circle of Willis. Thus these patients may be at increased risk for a cerebrovascular accident.Physical examination should be directed toward the comparison of the right-sided versus left-sided blood pressures and upper versus lower extremity pressures. The electrocardiogram (ECG) may show left ventricular hypertrophy. Magnetic resonance imaging may be a useful means of confirming the diagnosis in a pregnant patient.The pathophysiologic manifestations include a fixed obstruction to aortic outflow and distal hypoperfusion. The cardiovascular demands of pregnancy tend to exacerbate both the risk and consequences of this lesion. Attention should be directed toward maintaining normal to slightly elevated SVR, a normal to slightly increased heart rate, and adequate intravascular volume. In patients with uncorrected coarctation, neuraxial anesthesia should be administered with great caution, if at all. For cesarean section, general anesthesia is preferred. Remifentanil has been used and facilitates maintenance of hemodynamic stability. Invasive hemodynamic monitoring can help guide the administration of intravenous fluids. Uterine perfusion pressure is usually reflected more accurately by using a postductal intraarterial catheter instead of a preductal catheter. Ephedrine and dopamine are the vasopressors of choice because of their mild positive chronotropic effects.
29 CUIDADOS ESPECIALES TETRALOGIA DE FALLOT SD EISENMENGER 5% DE EMBARAZADASCIANOSISECOCARDIOGRAFIAEKGSD EISENMENGERSHUNT DER-IZQUIERDASINTOMASMORTALIDAD MATERNATROMBOEMBOLISMOANALGESIATetralogy of Fallot DEFECTO SEPTOVENTRICULARHIPERTROFIA VDESTENOSIS PULMONARAORTA ANULARTetralogy of Fallot accounts for 5% of cases of congenital heart disease in pregnant women. This lesion includes four components: (1) a VSD, (2) right ventricular hypertrophy, (3) pulmonic stenosis with right ventricular outflow tract obstruction, and (4) an overriding aorta (i.e., the aortic outflow tract receives blood from both the right and left ventricles). Tetralogy of Fallot is the most common congenital heart lesion associated with a right-to-left shunt. Patients typically present with cyanosis.INTERACTION WITH PREGNANCYIn the absence of corrective surgery, the number of women who reach childbearing age and become pregnant is quite small. Most pregnant women with tetralogy of Fallot have had corrective surgery. The surgical treatment, typically performed in childhood, involves closure of the VSD and widening of the pulmonary outflow tract. This surgery generally is successful and results in an asymptomatic patient. In some cases, a small VSD may recur, or progressive hypertrophy of the pulmonary outflow tract may occur slowly over the first several decades of life. The cardiovascular changes of pregnancy (e.g., increased blood volume, increased cardiac output, decreased SVR) may unmask these previously asymptomatic residua of corrected tetralogy of Fallot. The severity of symptoms depends on the size of the VSD, the magnitude of the pulmonic stenosis, and the contractile performance of the right ventricle. Patients with corrected tetralogy of Fallot, even if they have been asymptomatic for many years, should undergo echocardiography before and during early pregnancy.ANESTHETIC MANAGEMENTAnesthetic management for patients with successful correction of tetralogy of Fallot often does not differ from that for a woman without this lesion. Patients with corrected tetralogy of Fallot may manifest various atrial and ventricular arrhythmias, owing to surgical injury to the cardiac conduction channels. Thus a 12-lead ECG and ECG monitoring during labor are desirable.Greater attention should be given to the parturient with uncorrected tetralogy of Fallot or corrected tetralogy of Fallot with residua. The anesthesiologist should avoid causing a decrease in SVR, which increases the severity of right-to-left shunt. It also is important to maintain adequate intravascular volume and venous return. In the presence of right ventricular compromise, high filling pressures are needed to enhance right ventricular performance and ensure adequate pulmonary blood flow. Administration of a neuraxial block during early labor is advisable and helps prevent an increase in pulmonary vascular resistance and consequent right-to-left shunting. For cesarean delivery, regional anesthesia should be administered slowly; single-shot spinal anesthesia is a poor choice because the abrupt reduction in SVR may cause shunt reversal and hypoxemia.Eisenmenger SyndromeA chronic, uncorrected left-to-right shunt may produce right ventricular hypertrophy, elevated pulmonary artery pressures, right ventricular dysfunction, and ultimately, the syndrome first described by Eisenmenger in 1897. The primary lesion may be either an ASD or VSD, or an aortopulmonary communication, such as PDA or truncus arteriosus. The pulmonary and right ventricular musculature undergoes remodeling in response to chronic pulmonary volume overload. High, fixed pulmonary arterial pressure gradually limits flow through the pulmonary vessels. A reversal of shunt flow occurs when pulmonary artery pressure exceeds the level of systemic pressure. The primary left-to-right shunt becomes a right-to-left shunt. Initially the shunt may be bidirectional; acute changes in pulmonary vascular resistance or SVR may influence the primary direction of intracardiac blood flow. However, the pulmonary vascular occlusive disease ultimately leads to irreversible pulmonary hypertension. Therefore correction of the primary intracardiac lesion is not helpful at this stage.The clinical manifestations of Eisenmenger syndrome include the sequelae of arterial hypoxemia and right ventricular failure (e.g. dyspnea, clubbing of the nails, polycythemia, engorged neck veins, peripheral edema).These women often are unable to respond to the increased demands for oxygen during pregnancy. Maintenance of satisfactory oxygenation requires adequate pulmonary blood flow. The decrease in pulmonary vascular resistance seen in normal pregnancy does not occur in these women because pulmonary vascular resistance is fixed. The decrease in SVR associated with pregnancy tends to exacerbate the severity of the right-to-left shunt. The pregnancy-associated decrease in functional residual capacity also may predispose the patient to maternal hypoxemia. Maternal hypoxemia results in decreased oxygen delivery to the fetus, which results in a high incidence of intrauterine growth restriction (IUGR) and fetal demise. Maternal mortality is as high as 30% to 50% among these patients.   Thromboembolic phenomena are responsible for as many as 43% of all maternal deaths in patients with Eisenmenger syndrome. Many of these deaths occur postpartum—as late as 4 to 6 weeks after delivery.OBSTETRIC MANAGEMENTPatients with Eisenmenger syndrome who become pregnant should be counseled to terminate the pregnancy. If the patient desires to remain pregnant, a multidisciplinary approach with close communication among the obstetrician, cardiologist, and anesthesiologist is essential. The obstetrician most likely will want to perform an early instrumental vaginal delivery to minimize maternal expulsive efforts. Some obstetricians favor prophylactic anticoagulation during the intrapartum period, but it is unclear whether this improves maternal outcome.The primary goals of anesthetic management are as follows   : 1 Maintain adequate SVR. 2. Maintain intravascular volume and venous return. Avoid aortocaval compression. 3. Prevent pain, hypoxemia, hypercarbia, and acidosis, which may cause an increase in pulmonary vascular resistance. 4. Avoid myocardial depression during general anesthesia.Treatment of Pulmonary HypertensionInhaled nitric oxide (iNO) selectively dilates the pulmonary vascular bed without producing systemic hemodynamic effects. Thus, iNO can improve right ventricular function and may consequently enhance left ventricular function by improving oxygenation. Experience with iNO in parturients is limited. Goodwin et al. reported its use during the second stage of labor and postpartum in a parturient with Eisenmenger syndrome. The administration of iNO was associated with an improvement in the patient's hypoxemia and a reduction in her pulmonary artery pressure. It was discontinued after 48 hours and vasodilator therapy was maintained with an infusion of prostacyclin; however, the patient died 2 days later. In a similar case the woman died 3 weeks postpartum. However, use of iNO has been associated with good outcome in women with severe primary pulmonary hypertension.LaborSupplemental oxygen should be provided at all times. The pulse oximeter is the most useful monitor for detecting acute changes in shunt flow. Pollack et al. described the simultaneous use of pulse oximeters on the right hand and left foot of a parturient whose severe Eisenmenger syndrome resulted from an uncorrected PDA. The right hand receives preductal blood flow, whereas the flow to the lower extremities is postductal. Thus the authors could rapidly estimate relative changes in shunt fraction.An intraarterial catheter facilitates the rapid detection of sudden changes in blood pressure, and a central venous pressure (CVP) catheter can help reveal clinically significant changes in cardiac filling pressures. However, the insertion of a CVP catheter occasionally produces complications (e.g., air emboli, infection, hematoma, pneumothorax), which can be disastrous in these patients. Although some physicians have stated that a pulmonary artery catheter is “essential” for the intrapartum management of pregnant women with Eisenmenger syndrome, we and others   disagree and believe that a pulmonary artery catheter may be relatively contraindicated for several reasons. First, it is difficult, if not impossible, to properly position the balloon-tipped, flow-directed catheter within the pulmonary artery. Second, if the catheter does go into the pulmonary artery, the risks of pulmonary artery rupture and hemorrhage are great. Third, these patients may not tolerate catheter-induced arrhythmias. Fourth, measurements of cardiac output by thermodilution are uninterpretable in the presence of a large intracardiac shunt. Fifth, pulmonary artery pressure monitoring rarely yields clinically useful information in the presence of severe, fixed pulmonary hypertension. Sixth, the pulmonary artery catheter may predispose to pulmonary thromboembolism. Finally, the risks of placing/using a pulmonary artery catheter include the entire spectrum of complications associated with placement of a CVP catheter.Effective analgesia is necessary to prevent labor-induced increases in plasma catecholamines, which may further increase pulmonary vascular resistance. During the first stage of labor, intrathecal administration of an opioid is ideal, because it produces profound analgesia with minimal sympathetic blockade. For the second stage of labor, epidural or intrathecal doses of a local anesthetic and an opioid will provide satisfactory analgesia; alternatively, a pudendal block can be placed early in the second stage of labor. In some instances, maternal anticoagulation may complicate or contraindicate the use of regional anesthetic techniques. In such cases an intravenous infusion of remifentanil, with or without patient-controlled analgesia (PCA), may be the next best option. However, the quality and reliability of intravenous opioid analgesia is not as good as that provided by a regional anesthetic technique.Cesarean SectionHistorically, anesthesiologists have avoided regional anesthesia because the vasodilation that accompanies sympathectomy can worsen a right-to-left shunt. However, favorable outcomes have been achieved with epidural anesthesia, which has become the technique of choice for parturients with Eisenmenger syndrome.   The key to the safe use of spinal or epidural anesthesia is incremental injection of local anesthetic while carefully correcting any adverse hemodynamic sequelae. It is critical that the anesthesiologist avoid aortocaval compression and maintain adequate venous return. Intravenous crystalloid and small doses of phenylephrine are administered as needed to maintain maternal preload, SVR, and oxygen saturation.Several disadvantages are associated with the use of general anesthesia. Positive-pressure ventilation results in decreased venous return, which compromises cardiac output. The volatile halogenated agents can cause myocardial depression and decreased SVR. Rapid-sequence induction with agents such as thiopental or propofol characteristically decreases both contractility and SVR, which may exacerbate a right-to-left shunt. On the other hand, a slow induction of general anesthesia predisposes to maternal aspiration. This risk notwithstanding, a rapid-sequence induction of general anesthesia is usually avoided in patients with Eisenmenger syndrome. Measures to decrease the risk of anesthesia-related aspiration include (1) maintaining the patient NPO for solids for at least 8 hours before the induction of anesthesia, (2) preoperative pharmacologic therapy (e.g., H2-receptor antagonist, metoclopramide, sodium citrate), and (3) the use of cricoid pressure. Although opioids are not routinely used when giving general anesthesia in healthy women undergoing cesarean section, it seems appropriate to include a systemic opioid during administration of general anesthesia to help maintain hemodynamic stability in women with severe cardiovascular disease.Regardless of the anesthetic technique used, these women are at high risk for hemodynamic compromise immediately after delivery. Large losses of blood should be replaced promptly with crystalloid, colloid, and/or appropriate blood products. Cautious fluid therapy is important when the blood loss is minimal, because the postpartum autotransfusion may cause intravascular volume overload in women with myocardial dysfunction.to Colleague Print Version
30 PROFILAXIS PARA ENDOCARDITIS 1/8.000 PARTOS29% MORTALIDAD MADRE23% MORTALIDAD FETALCOLEGIO A. G/O: NO USARACC/AHA :ANTES DEL PARTO VAGINALRUPTURA DE MEMBRANASVALVULAS PROTESICASENFERMEDAD CARDIACA CIANOSANTESHUNTENDOCARDITIS PREVIA
31 HIPERTENSIÓN PULMONAR PRIMARIA MORTALIDAD 30-40%ASOCIADO A:RCIUMORTINATOPARTO PRETERMINOPREVENIR:HIPOXEMIA, HIPERCAPNIACOMPRESIÓN AORTOCAVAHTP FIJAPRIMARY PULMONARY HYPERTENSIONThe syndrome of primary pulmonary hypertension is characterized by markedly elevated pulmonary artery pressures in the absence of an intracardiac or aortopulmonary shunt. Unlike those with Eisenmenger syndrome, patients with primary pulmonary hypertension often have a reactive pulmonary vasculature that can respond to vasodilator therapy. The maternal mortality rate may be as high as 30% to 40%. These patients also have a high incidence of IUGR, fetal loss, and preterm delivery.The hemodynamic goals of obstetric and anesthetic management are similar to those for the patient with Eisenmenger syndrome   : 1 Prevent pain, hypoxemia, acidosis, and hypercarbia, which cause an increase in pulmonary vascular resistance. 2. Maintain intravascular volume and venous return. Avoid aortocaval compression and replace blood loss at delivery. 3. Maintain adequate SVR, as women with fixed pulmonary hypertension cannot increase their cardiac output to compensate for a decrease in blood pressure that results from a decrease in SVR. 4. Avoid myocardial depression during general anesthesia, especially in women with fixed pulmonary hypertension.Supplemental oxygen is a superb pulmonary vasodilator and should be administered routinely in these patients. Monitoring typically includes placement of both an arterial and a CVP catheter. A pulmonary artery catheter can guide treatment when the pulmonary vascular resistance (PVR) is responsive to vasodilator therapy; however, the physician should weigh carefully the risks versus benefits of pulmonary artery catheterization (vide supra). Transesophageal echocardiography has been used intraoperatively during cesarean delivery.Agents that have been used to treat primary pulmonary hypertension include iNO, nitroglycerin, calcium-entry blocking agents, prostaglandins, and endothelin antagonists.       A successful maternal and fetal outcome was recently reported in a woman with primary pulmonary hypertension who had received epoprostenol throughout pregnancy.Continuous neuraxial block is preferred for labor and delivery.   Epidural anesthesia allows for a pain-free first and second stage of labor and facilitates elective forceps delivery. Several reports have noted the successful use of epidural anesthesia for cesarean section.   Slow induction of epidural anesthesia is of critical importance. If hypotension occurs it should be treated initially with intravenous fluid. Vasopressors such as ephedrine should be used with caution because these agents can further increase the pulmonary artery pressures. Single-shot spinal anesthesia may cause severe hemodynamic instability and should be avoided except in those rare instances when it is used in preference to general anesthesia. Continuous spinal anesthesia and general anesthesia have also been successfully used in patients with primary pulmonary hypertension.Weeks and Smith reviewed all published cases of intrapartum anesthetic management for women with primary pulmonary hypertension. They concluded the following:Epidural anesthesia has been used with success, but in the presence of pre-existing right ventricular failure, any large decrease in systemic vascular resistance may lead to a further decrease in cardiac output. Refractory hypotension may also cause right ventricular ischemia, leading to a further deterioration in right ventricular function. The potential hazards of general anesthesia include increased pulmonary artery pressure during laryngoscopy and intubation, the adverse effects of positive pressure ventilation on venous return and the negative inotropic effects of certain anesthetic agents. However, these adverse effects can be minimized by the use of a narcotic-based induction and maintenance technique. Any resulting narcotic-induced neonatal depression should be easily treated. Intensive postoperative management is of critical importance and should probably continue for one week because of the high incidence of sudden death during this period.
32 HIPERTENSIÓN PULMONAR PRIMARIA CATETER CENTRALECOTRANSESOFAGICOTTO:OXIDO NITRICO, NITROGLICERINABLOQ CANALES DE CALCIOPROSTAGLANDINASANTAGONISTA DE LA ENDOTELINAANESTESIA ESPINAL CONTINUA
33 CARDIOMIOPATIA HIPERTROFICA OBSTRUCCIÓN TRACTO DE SALIDA.PREVENIR:TAQUICARDIARESISTENCIA VASCULARCOMPRESIÓN AORTOCAVAARRITMIAMUERTE SUBITA
35 ENFOQUE EVALUACIÓN DEL RIESGO PLANIFICACIÓN OPTIMIZACIÓN DEFINIR LA SITUACIÓN OBSTETRICA
36 RESUMEN RIESGO SEVERO LESION ESTENOTICA VI NECESIDAD DE ANTICOAGULACIÓNHTP SEVERAEISSENMENGERINSUFICIENCIA PULMONAR SEVERAFUNCIÓN SISTOLICA VDELEVACIÓN BNP
37 Kee W D, Shen J, Chiu A T, Lok I, Khaw K S. Combined spinal- epidural analgesia in the management of labouring parturients withmitral stenosis. Anaesth Intensive Care 1999; 27: 523–526.23. Van de Velde M, Budts W, Vandermeersch E, Spitz B. Continuousspinal analgesia for labor pain in a parturient with aortic stenosis.Int J Obstet Anesth 2003; 12: 51–54.