Caesarean Section – Blood Transfusion
Clearance of Fetal Products and Subsequent Immunoreactivity of Blood Salvaged at Cesarean Delivery.
Fong J, Gurewitsch ED, Kump L, et al (Cornell Univ, New York)
Obstet Gynecol 93:968-972, 1999
The findings were that fetal debris was found in blood salvaged 4 minutes after the placenta was removed. Although humoral material is cleared, fetal blood cells are still present in all postprocess salvaged blood. On cross-matching, the product was compatible with maternal blood. Its supernate did not immunoreact with maternal serum.
Editorial comment : In instances of severe intraoperative hemorrhage during pregnancy, the use of salvaged blood employing a cell saver system is often suggested the risk of embolization from particulate matter in salvaged blood and isosensitization from the infusion of incompatible fetal erythrocytes.
Fetal hemoglobin containing red cells from 0.2% to 1.0% is found in salvaged blood. Where the potential for maternal Rh sensitization exists, the authors recommend that samples of saved cells be submitted for Rhogam dose determination. Salvaged blood cross matched with maternal blood and failed to demonstrate antigen antibody precipitate complexes. This to be also provides a strong basis for informed consent in association with the use of the cell saver when such blood is use for autotransfusion.
Sara Paterson- Brown
Elective Caesarean Section – A Woman’s Right to Choose?
Progress in Obstetrics and Gynaecology-14, Year-2000, Pg.202
Traditionally, caesarean sections [CS] have been reserved for those situations where labour or vaginal delivery have been considered dangerous to either mother or baby and high rates of caesarean sections are met with knee-jerk reactions of disapproval. There is no evidence to support any specific target rate, however, and the recent drive in America to reduce the caesarean sections rate to 15% by the year 2000 have been criticized as causing increased maternal and fetal damage.
Although caserean section is becoming increasingly safe and evidence is mounting regarding risks of labour and vaginal delivery, there is no doubt that the evidence, as it stands, remains grossly incomplete. Despite this, the balance of acceptability between abdominal and vaginal delivery is changing. Whether maternal choice should be added to this equation when deciding how to deliver a woman is the subject of this review.
Ethics of Choice
Patient’s right to refuse or limit treatment is well tested and universally acknowledged, but the opposite right to request certain interventions, while perfectly acceptable in many situations, seems to have caused significant controversy when relating to caesarean sections.
Examples of Choice in Obstetrics and Gynaecology
Patients assert positive rights when requesting definitive treatment for unpleasant, but not dangerous, conditions: such as menorrhagia or urinary incontinence and even sterilisation to save themselves the daily inconveniences of contraception. How can we discredit ‘positive right’ in the context of patient choice for caesarean sections when we live with it in so many other professional situations?
Current Guidance on Choice
In UK, clinical governance is going to become a part of everyday life, and the booklet brought out by the General Medical Council on good medical practice guides us to patient choice quite deliberately: ‘patients want to be sure that their doctors respect their views and wishes when treating them’, and medical and clinical teams must have a positive attitude to patients and listen to their wishes and needs.
Balance of the Risks
It is interesting to reflect on an obstetric situation where there is patient and/or obstetrician anxiety: a woman with an uncomplicated pregnancy of a well-grown singleton fetus at term who has had a previous obstetric catastrophe of non-recurring cause, or previous numerous first trimester miscarriages, or prolonged infertility treatment. A perfectly common and acceptable course of action in these scenarios is for her to be delivered by electives CS at term. If we believe this is truly the safest way to deliver these ‘precious’ pregnancies, why do we not afford all mothers and babies similar concern?
To take argument further, we must explore the risks to infant and mother of elective CS versus labour [ labour as opposed to vaginal delivery or normal delivery must be used as the comparator, as no woman entering labour can be guaranteed a particular type of delivery].
Risks of awaiting Spontaneous Labour:
Unexpected antepartum stillbirth, although tragic, is not uncommon and increases 8-fold from 0.7 per 1000 on-going pregnancies at 37 weeks to 5.8 per 1000 ongoing pregnancies at > 43 weeks. If the risk of death increases as gestation advances from 37 weeks, what other lesser damage is occurring silently? We believe that less than 10% of cases of cerebral palsy are attributable to intrapartum insult and most are accounted for by antenatal events – we do not know what proportion of these occur at term. If subtle changes are effecting death, it is not unreasonable to suppose that lesser insults could effect damage at this time. This problem requires much more attention and research, but at present is a significant factor to remember when balancing elective delivery at 39 weeks against awaiting indefinitely for spontaneous labour to ensue.
Risks of Labour
Neonatal encephalopathy occurs at a rate of about 1 in 260 term babies of which 15% are directly attributable to intrapartum events, i.e. 1 in 1750 labours. Ingemarson et al conducted a 4-year follow-up on 102 babies born with an umbilical cord gas pH of less than 7.05 and compared them with 100
Controls and found significant speech deficits in those infants who had been acidemic at birth [19 of 102 compared to 8 of 100, respectively, [P= 0.03].
Risks of Vaginal Delivery
During vaginal delivery, the baby may sustain birth trauma in different ways and the problem is that, by definition, such damage is unexpected. Even when considering shoulder dystocia, most cases occur in babies not deemed to be macrosomic before [or even after] delivery. Instrumentation may be needed with risks of laceration or nerve palsies from the use of forceps, or of cephalohaematoma or retinal hemorrhages from ventouse extraction. Quantifying these complications is complex, as it depends on the obstetric population and the intrapartum care provided, but is not insignificant.
Risks of Elective Caesarean Sections
Electively delivering a baby abdominally pre-empts spontaneous labour reflective of fetal maturity and also deprives it of this physiological [if sometimes dangerous] stress: hence, such babies may be disadvantaged. There is good evidence demonstrating that, in the immediate postnatal period, respiratory function is more likely to be compromised in infants delivered by elective caesarean sections. In practical terms this risk can be minimised by delaying elective delivery until 39 completed weeks gestation, where the combined risk of transient tachypnoea and respiratory distress syndrome occurs in 1.8% of infants.
There is a complete lack of evidence concerning bonding and breast feeding in mother-baby pairs where the caesarean section was requested in the absence of pathology.
Long-term Fetal Effects from Different Modes of Delivery
Clearly, further work needs to be done in this area.
All caesarean sections, whether elective or emergency, prelabour or intrapartum, are usually grouped together, and have been performed for clinical reasons including maternal disease, rather than for maternal choice in otherwise healthy individuals. It is, therefore, hardly surprising that mortality, morbidity and satisfaction are worse in the caesarean section groups.
Evidence available from South Africa is that those women who require a caesarean sections are more likely to die than those women who achieve a successful vaginal delivery. The ratio of risk corrected for the reasons for the caesarean sections are approximately 5:1 CS versus vaginal delivery, and 1.5:1 for emergency intrapartum versus elective CS. This is obviously a hugely important area.
This is supported by the observation that there has yet to be a death reported in the UK of a previously fit woman who has undergone an elective CS under epidural anaesthetic with thromboprophylaxis and antibiotic cover.
In Massachusetts, a study looking at 2,803596 live-births from 1954-1985 found that, although the caesarean section rate quadrupled, the maternal mortality rate remained constant. The maternal death rate directly attributable to these clinically indicated CS was 5.8 per 100,000 CS deliveries, while the total death rate in women delivered vaginally was 10.8 per 100,000 vaginal deliveries. This puts death rates more into perspective, but with such low death rates in those countries not only able to provide safe conditions for CS but also able to audit them, it will take some time before this risk is fully appreciated in those few otherwise fit women who have a CS purely for maternal choice.
The results of many of these trials are conflicting, but the most recent and largest studies demonstrate that elective cesarean section appears safer than trial of scar or trial of breech delivery.
Short-term risks relative to mode of delivery
Short-term morbidity after elective caesarean section has been quantified by Obwegeser et al as 2% urinary infections, 1% wound infection and 12% maternal anaemia in a group of 108 women undergoing elective caesarean section for breech presentation. More recently, elective CS and vaginal delivery both had maternal morbidity rates of less than 2% while in those having emergency CS, rates approached 3%.
It is commonly believed that the general recovery after CS is slower than after vaginal delivery, but recent evidence from Scotland shows that instrumental vaginal delivery causes significantly more maternal morbidity than either CS or normal vaginal delivery.
The more we use regional analgesics for pain relief in labour the higher the instrumental vaginal delivery rate will be, and the real problem we have is that our social habits make this increasingly likely: how can we expect women to tolerate the severe pains of labour when our normal everyday habits are to avoid pain whenever possible.
Future obstetric performance after CS
The fact remains that, in the follow-up studies available, there are significant risks associated with future fertility.
The incidence of placenta praevia and placenta accreta increase almost linearly after each previous CS and placental abruption is increased by 2-4 fold. As the risk of these complications increases the more children a women has, her future reproductive intention is very relevant to any individual woman’s caesarean threshold.
Although all women entering labour face the risks of emergency CS, instrumental vaginal delivery and perineal trauma, the majority will achieve a normal vaginal delivery giving them an enormous sense of achievement and fulfillment. Whatever the outcome, however, the pain experienced – which can be combined with overwhelming fear and a feeling of loss of control – can have profound effects on the woman both short and long-term. This can have tremendous implications for the woman’s future and especially on sexual relations and childbearing. The evidence available to suggest CS is traumatic does not relate to those done for choice where we have no evidence either way.
Long-term problems from vaginal delivery
The anal sphincter is ruptured in 35% of women with their first vaginal delivery. Only a few of these are diagnosed clinically and, of those recognized and repaired, 85% will still have a defect at follow-up, with 50% being symptomatic. One of the problems with anal incontinence is the embarrassment women feel and, therefore, this condition is very under-reported. Urinary incontinence occurs in up to a third of women after vaginal delivery and 11% life-time risk of requiring surgery for either urinary incontinence or prolapse.
Thromboprophylaxis, antibiotics, regional blockade and early mobilization should already be standard practice, but we need to work more on surgical techniques to establish the optimum uterine closure, to reduce the likelihood of future placentation complications.
Despite the fact that active management of labour has yet to be proved effective in any randomised trial, there can be no doubt of the value of intensive one-to-one care of women appropriately prepared antenatally. How valuable early amniotomy is will remain debatable, but the process of accurate diagnosis of labour is something that few units can boast of or adult. Let us not forget that 45% of the intrapartum deaths investigated by CESDI had suboptimal antepartum care.
As doctors we must do no harm, yet this does not mean doing nothing, and it remains that the pregnant woman needs to be delivered either vaginally or abdominally. CS us a surgical procedure and, as such, could be considered ‘unnatural’. Hence, the human has a large brain with which to think and a narrow pelvis with which to move. Natural selection is taking us towards more difficult childbirth which we are intelligent enough to overcome.
Not Feasible Logistically
This is not proved. On first impressions, one may think that performing CS for choice would increase the work-load significantly, but the demand is likely to be very small. Midwives are in very short supply in the UK, which is sadly something that is unlikely to improve in the short-term and, therefore, planned delivery and maximizing health care assistant roles in the postnatal period could be seen as more efficient, cost effective and also ;potentially achievable.
THE LIKELY DEMAND
Obstetricians are clearly exposed to the worst of the obstetric scenarios and, therefore, it is perhaps not surprising that, when London obstetricians were questioned about their preferences in the hypothetical situation of being at term with uncomplicated singleton cephalic fetus, a not insignificant minority [17%] would opt for CS for themselves or their partner. The noteworthy feature of the al-Mufti study is not as much the overall CS preference rate but the female to male differences; 31% of females as opposed to 8% of males would choose an elective abdominal delivery in a completely uncomplicated pregnancy of a singleton cephalic fetus at term. This difference in choice between men and women cannot be because of professional exposure on the labour ward. What then? Is it that women are more likely to describe their embarrassing symptoms to the female gynecologists or are the latter just more sympathetic to them?
We know that in Italy, where obstetricians are obliged to do what their patients request, 4% of women choose CS. We do not have comparable figures from the UK, but there is no doubt that maternal request has a big impact on CS for less than completely normal circumstances. Jackson and Irvine demonstrated that 38% of all elective CS done in a district general hospital in the UK were for maternal request in the absence of any contra-indication to vaginal delivery, mostly in women with previous CS scars, and we know from Australia and the US that 50% of women with a previous CS will request another one.
It is perhaps not so surprising that women are becoming intolerant of risk when one thinks how ‘expectant’ we have all become. Our lives are more safe and controlled now than even before: perinatal, infant and maternal mortality are at an all time low in the developed world, and we can plan our families and have prenatal diagnosis to reduce the likelihood of abnormality. It is, therefore, understandable, that some people will request a medicalised, controlled and safe method of delivering their baby.
Those who favoured technology over nature were comfortably in the majority. Cost and effectiveness issues need to be considered alongside woman’s views. If the two conflict obstetricians should support the woman not the auditor.
The trend for use of caesarean section, coupled with greater emphasis on individual autonomy has clearly progressed too far for a return to paternalistic directions to women on how they should give birth. Instead of emphasis should be on comparisons of the implications of vaginal versus CS delivery. The uptake of CS in women made aware if such information will clearly be more appropriate than any current ‘desirable’ targets.
One professional worry is that obstetricians are in danger of becoming technicians and shedding responsibility for their actions by ‘blaming’ patient choice.
Message to the Public
Emergency CS in labour is the worst of all worlds and should be avoided by appropriate antenatal planning and rigorous intrapartum care.
The risks of CS and labour are real but different, and if fully explained to the woman, she should be allowed to accept one set of risks over the other – after all she is the person who has to live with the consequences. An elective CS in a fit healthy woman is neither unsafe nor bad practice if she truly understands the risks involved and is adamant that she cannot accept the risks of labour or vaginal delivery.
Rainaldi MP, Tazzari PL, Scagliarini G, et al [ Policlinico S Orsola, Bologna, Italy]
Blood Salvage During Caesarean Section
Br J Anaesth 80: 195-198, 1998
Introduction – There is interest in the possibility of reinfusing intraoperatively salvaged blood in women undergoing cesarean section. The recovered red cells would have to be free of contaminants and major antigenic incompatibilities. A study of blood salvage during cesarean section, including its effects on perioperative hemoglobin concentration and postoperative hospital stay, is reported.
Methods – The randomized trial included 68 patients undergoing cesarean section. One group of patients underwent intraoperative blood salvage, while the other served as a control. Blood salvage was carried out under guidelines, including identification of maternal and fetal blood group, avoidance of umbilical cord blood, starting salvage after removal of the fetoplacental unit, completely filling the centrifugation bowl with red cells, using at least 1,000 ml of physiologic solution per bowl to wash the cells, and mixing the contents of the bowl. The last step was intended to eliminate the buffy coat where fetal cells were located.
Results – The mean amount of blood salvaged in the salvage group was 363 mL. Only 3% of these patients received homologous blood transfusions, compared with 24% in the control group. Patients in the salvage group had higher hemoglobin concentrations during the first 4 days after cesarean section, despite the fact that their baseline hemoglobin was lower. They also had a shorter duration of hospitalization, 5 vs. 7 days.
Editorial Comments- Bernstein et al [Abstract 3-23] state that “intravascular injection of amniotic fluid may lead to the syndrome of amniotic fluid embolism.” Yet studies have consistently demonstrated that intravascular injection of amniotic fluid does not result in amniotic fluid embolism [ AFE] in laboratory animals. Further, clinical observations suggest that intravascular maternal exposure to fetal tissue and debris is a common occurrence during labor and delivery, even in women who manifest no evidence of AFE. Thus, Clark et al’ have suggested that the term AFE is a misnomer, and that this syndrome may result from an abnormal response to amniotic fluid or its contents, rather than from an embolic event per se. Clark et al have suggested that the term AFE be replaced with the term anaphylactoid syndrome of pregnancy.
The decision to perform intraoperative blood salvage is not a trivial one. However, given the rarity of AFE and the possibility that this syndrome results from an abnormal [perhaps anaphylactoid] response to an unknown quantity of amniotic fluid, it is premature to conclude that intraoperative blood salvage does not have some [albeit small] risk of adverse maternal response.