Clinical Case 075: a CTG, a VE and a distant ECHO
This is a rare case. One where I was at a bit of a loss as to which was the best option. So keen to get your input!
A 23 yo. woman G?1, P0 – was flown in from a remote community in “threatened premature labour”, she was estimated to be about 34 weeks (but unclear on dates / late scans / possible IUGR). She had not had much antenatal care, however her old notes were pulled….
She had a history of pretty bad rheumatic heart disease in her teens and had previously been diagnosed by the visiting Cardiologist as having severe mitral regurgitation and moderate aortic valve incompetence. We didn’t have a recent ECHo but one from 2 years ago showed the same picture – severe MR, mod AR and preserved LV function. Of course 2 years and a pregnancy can change a lot of things – so we were unsure as to her current cardiac function. On history she did complain of mild exertional dyspnoea, though no chest pain. Never had an episode of APO.
OK – so once she arrived it was clear that she was in fact in labour. She was having 5 – 10 minutely, moderate contractions. Her VE revealed a 4 cm cervix. The CTG was looking OK though a baseline tachycardia was evident.
Now – the mantra of premature labour in remote Australia is “in utero transfer” – we know that keeping the fetus in the uterus and delivering in a tertiary centre improves outcomes. So we opt for tocolytics in TPL wherever viable.
Back to the case: we want to stop the contractions – our usual drugs are nifedipine, salbutamol and a prayer! So, can we use these agents in a woman with a potentially fragile cardiac output? What are the potential issues for this lady?
An hour later the labour was slowing but…. the CTG was not looking good. She had had a few decelerations, and just now a long, low decel to 60/min. OK – now this bub needs to come out.
She will need an anaesthetic – the tradition is a spinal / subarachnoid block with some vasopressor support. We don’t want to do a GA if at all possible. So what do we need to think about in a woman with relatively severe MR / AR? What are the potential pitfalls?
Just for fun – what would change if she has mitral stenosis or aortic stenosis as a result of her rheumatic disease?
Let me know
Casey
OK this is not an obstetric problem, this is an anaesthetic one. So I’ll shut up and read the pearls from people who know what they are talking about!
For tocolysis may I suggest an Indomethacin suppository?
Trial underway Bernie – http://clinicaltrials.gov/ct2/show/NCT00486824
Indocid has been associated with PDA and NEC in neonates in the past , have you got any other papers on it?
Casey
Gotta love the Kimberley Kurlies! The relatively mild exertional symptoms are reassuring, but I wholeheartedly agree that one alive patient is better than two dead. A ten minute phonecall to one of the cardiac anaesthesia or cardiology consultants at a teaching hospital will help soothe the nerves. Ensuring she has adequate intravascular before starting and having the phenylephrine or Aramine infusion up and running before you start and ready to bolus to maintain her preload. The later questions about mitral stenosis present a more hairy situation IMHO.
A cat among the pigeons perhaps…..why not go for IV Special K instead of a regional? Faster and more cardiovascularly stable? I haven’t gone looking for papers in this situation, perhaps others have?
Great site Casey, I must have been under a rock to have missed this for so long!
Hi Airell
Seems like a long time since you sat in on my first list as a GP-anesthetist!
As fate would have it I spent 45 fruitless minutes trying to get a specialist of any description to call me back. Apparently there were multiple other hospitals having a bad night that day! Ce la vie! As is often the case – we do what we know.
See my reply to Minh above. I think this is one scenario where you might change pressors – too much alpha squeeze could be a bad thing? No evidence for this, just physiologically makes sense to me. Agree with ensuring fluid load is ample – maybe use IVC. US… (haha, that is a joke in this patient)
I like the idea of a gentle epidural so we don’t shock the haemodynamics too much and then use ketamine as a back up plan when the inevitable pain comes as they fart around with packs and peritoneal stimulation.
Welcome to the site mate. Value your comments.
Casey
Hi – I am no aesthetician as well, so I am not able to answer. But I’m asking since I couldn’t find a definite answer on the internet – what do APO and TPL mean?
Sorry
APO = acute pulmonary Oedema
TPL = threatened premature labour
ok nice one..not!
whats the VE show now..ie cervix exam? No point going to LSCS if fully dilated !
assuming its not changed or not favourable cervix for rapid Vaginal delivery and the decision is to go to emergent LSCS…
dont feel pushed into doing something that you are not prepared for ..better to prepare and take your time and have an alive mother instead of two dead patients.
Call for specialist anaesthetic and obstetric advice if need be. Do a careful bedside cardiac USS for LV contractility. Prepare your OT staff and team. Get blood on standby if you can..or call for it to come on the retrieal plane if need be!
If LV contractility looks decent on eyeball exam USS then feel more confident that standard anaesthetic technique should be fairly safe including spinal block. If LV contractility looks below average or clearly abnormal, high risk anaesthetic and suggests a cautious RSI for me
basic principles in left side valvular regurg are avoid tachycardia and hypotension
watch the amount of IV fluids you give especially if already have given salbutamol for tocolysis..certainly dont forget to stop salbutamol infusion if decision to deliver! It would not have been my first choice tocolytic in this woman!
Risk of pulmonary oedema is above average in this cAse and increased with salbutamol use, which always causes tachycardia.
RSI wise, be generous with analgesia, dont worry too much about recall, decent dose of NMB, get tube in quickly. baby takes its chances with whatever induction agents, sedation, analgesics you decide to give to keep mum just anaesthetised,
but dont worry too much. this is an emergency, you got two patients to try to keep alive.
stick to basic anaesthetic principles and dont get too stressed by the cardiac issues. If you plan carefully, get advice, document your plan and communicate with mum/family for consent, dont rush it, stick to basic anaesthesia
even if baby dies but mum lives, you will know you did your best
Hi Minh
My understanding is that the plan with AR would be to avoid too much increase in SVR ( aramine, etc) keep the volume up to the right side, and aim for relative tachy, not wanting Brady as this increases the is stolid regurg fraction?
I think my plan was to go for an epidural with a relatively slow build up of block to allow the heart to compensate. A GA is also ok if you are careful, ketamine maybe? Bit scary though if the airway is looking tricky – I usually opt for a block if I cn do it safely
Thanks
Any really smart obstetric anaesthetists out there can help?
C
Hi Casey,
Good case, I am an obstetric anaesthetist and we do see quite a few of these patients at KEMH (women’s hospital in WA), usually we are lucky as they have been worked up properly. However sometimes they haven’t had recent ECHO’s are pretty poor historians and we see them for the first time when they arrive in theatre with foetal distress, so I know the feeling!
For those of you clever ED guys who can do bedside ECHO you’re already ahead of me, although if it isn’t really going to change what you do or is technically difficult and clinically the mother is fine I would suggest you should omit this and keep it up your sleeve for later if things don’t go smoothly…??? If the mother had pulmonary oedema, or shock etc then different story.
When there are signs of foetal distress try to buy yourself some time with in utero resuscitation, make sure there is no aortocaval compression so put her full left lateral, treat any maternal hypotension and consider a tocolytic to stop the contractions (in this scenario you have already started this).
As an obstetric anaesthetist I would :
– put in an arterial line, basically you want to keep haemodynamics normal and this is the easiest way to quickly notice when things go pear shaped….This is not essential to be honest if you don’t put many in or have trouble getting one in (don’t be afraid of using the brachial if reqd), an accurate NIBP, ECG and pulse oximeter will usually still tell you all you need.
What about anaesthetic technique?
Sometimes you can try to be too clever (my personal observation) keeping things simple is usually better.
With any patient and cardiac disease you just need try to keep their haemodynamics normal the technique doesn’t really matter as long as you do it carefully, there’s more than one way to skin a cat. Useful acronym for any cardiac disease I was told whilst studying for my exams was : ACRRAP
A – afterload, contractility, rhythm, rate, antibiotics, preload. But to be honest it makes it sounds more complicated than it really is as usually no matter what their cardiac lesion you aim to keep the preload normal, afterload normal, in sinus rhythm, maintain contractility, and consider antibiotics!
In this woman with regurgitation – keep BP lowish normal, heart rate highish normal
Also you shouldn’t try and use a technique you’ve never used before, stick with what you’re familiar with and do it well. (aka iv ketamine for me I’ve never done it for a CS).
All the other basics apply to this women coming for a urgent CS, in general regional is safer than GA because of lower incidence airway problems but you may still consider a GA for all the usual reasons ie if maternal refusal, failed regional / urgent threat to life of mother or foetus etc.
Spinal / CSE – probably what I would do but with an art line so you notice any hypotension early. It’s what i do for most CS, it’s reliable and works well and i like doing what I’m used to. I would treat the hypotension with my phenylephrine infusion which we use routinely for CS under spinal (100mcg/ml, starting at 30ml/hr), and treat bradycardia with glyco /atropine or ephedrine, maybe aim for BP syst 100-130, HR 70-100.
Epidural topup – slower onset but less likely to cause precipitous drop in BP.
GA – also reasonable especially if the severe foetal distress continued and she wasn’t obviously compromised. I would use propofol / sux, in normalish doses to be honest if the mother wasn’t obviously compromised (e.g. 70kg woman, propofol 200, sux 100 ) and maintain with sevo/N2O and treat haemodynamics as indicated.
iv ketamine – seems attractive on paper if you focue on the CVS disease as it keeps the HR highish, contractility high and preload / afterload up. However basically you are giving a GA without proper airway protection and serious aspiration / death is a real risk in an unfasted parturient having emergency intraabdominal surgery. Awareness is also possible and you don’t really know what the haemodynamics are going to do. To be honest I think it’s trying to be a little bit too clever however it is a legitimate option for some. I add ketamine to propofol for my induction in an RSI in shocked patients.
Oxytocic drugs and cardiac disease:
– Avoid big bolus of syntocinon, I would start an infusion 30u/500ml at 240ml/hr and give 1u bolus at a time up to 5units if required but spaced over 10min.
Misoprostal is usually ok and consider adding this in.
What about ergometrine (causes vasoconstriction, hypertension and rarely coronary vasospasm) and F2 alpha (hypertension and pulmonary vasocontriction) , well you could consider these also as major blood loss is also bad! however do it slowly and watch your haemodynamics, consider trying compression sutures eg (B-Lynch) by the surgeons first if they’re already in the abdomen as less downside to this.
Fluids
– Once again avoid hypovolaemia but don’t overload! sounds condescending but basically if they don’t bleed much don’t give them too much ie average blood loss – 500-700ml they probably should only get 2-3 litres crystalloid in the first 24 hours. most intraop hypotension is from our spinal / volatiles and judicious vasopressor, not lots of crystalloid is the best treatment.
– Monitor them closely postop for pulmonary oedema they are more prone to this.
I’ve probably forgotten something important but i hope this helps.
Roger
Roger’s advice is sound…KISS is my mantra.
Good to see Airell here.
i can think of one anesthetic option with minimal CV effects.. go local!
i have heard that in some parts of the world, pure local anesthesia for emergent (and maybe even elective) CS is still standard of care. yes, clearly has its disadvantages, but when you include the potential pitfalls of all those fancy systemic drugs..
see WHO guidelines, page P-7, here:
http://whqlibdoc.who.int/publications/2007/9241545879_eng.pdf