CEMACH

Chapter 18: Emergency medicine

Summary of key findings for 2003-2005

One hundred and ten reports of mothers who were admitted to Critical Care and who died were reviewed in detail. Of these, 63 deaths were attributed to Direct causes and 47 to Indirect causes. As in previous Reports the types of presentation were very varied. Some mothers suffered a sudden intra-cerebral event without warning and were admitted to a Critical Care Unit for a short period of ventilation prior to brain stem death tests. Almost without exception this process was well documented and in many cases appropriate organ donation was discussed. Other mothers suffered out-of-hospital cardiac arrests and despite extensive resuscitation attempts did not survive. For example:

A previously healthy woman in mid pregnancy developed severe one-sided back pain at home and collapsed. She arrived at the emergency department (ED) in cardiac arrest. The ED had been pre-warned by the paramedic crew and the critical care specialist registrar had already asked the consultant on call for critical care to attend. Shortly after admission an emergency caesarean section was performed by the emergency medicine consultant. Massive transfusion, tracheal intubation, external cardiac massage and defibrillation restored her cardiac output and she was transferred to the operating theatre by a consultant anaesthetist for a laparotomy by a consultant obstetrician to investigate continued bleeding. At operation she was found to have an aneurysm of the splenic artery which had ruptured. She received large amounts of blood including O negative, fresh frozen plasma (FFP) and aprotinin in an attempt to control the bleeding. Postoperatively she was transferred to the Critical Care Unit where a femoral arterial and a pulmonary artery catheter were inserted and she was started on continuous veno-venous haemofiltration. Despite the use of inotropic, ventilatory and renal support she developed multiple organ system failure and following a further bleed she died less than two days after admission.


It is difficult to fault any aspect of her management from the time of her collapse to her death. While no less of a tragedy to all involved, these cases probably represent a group of mothers in whom a significant reduction in mortality remains a difficult challenge. In contrast were a number of cases where, as in previous Reports, both the recognition and the subsequent management of a variety of life-threatening illnesses were considered to be sub-optimal.

Recognition of life-threatening illness

Delays in the recognition of life-threatening illness as a contribution to avoidable mortality are certainly not confined to maternal deaths. Controlled trials will always be difficult, if not impossible in this area, yet it seems intuitive that, in some cases at least, the earlier detection of severe pathology must lead to a better chance of survival. It is a common activity for critical care consultants to review a patient’s observation charts and criticise the delay in recognising that something serious was developing. This must however be interpreted with care, the benefits of hindsight are easy to overlook:

A woman with a past medical history of mild asthma presented to her local gynaecology unit early in her second trimester with a history of increasing shortness of breath. She was pyrexial on admission at 38 oC and with a C-reactive protein (CRP) level of 300 mg/l (normal < 10 mg/l), a provisional diagnosis of influenza was made and she was admitted for observation. Twenty-four hours later she was seen by a junior medical trainee who recorded that she had a silent chest, a markedly reduced peak expiratory flow rate and was coughing up green sputum. The medical team were not prepared to take over her care because she was pregnant. She was started on intravenous steroids, antibiotics and inhaled bronchodilators. Several discussions between junior medical staff and a consultant physician ensued and she was eventually seen by a medical specialist registrar and admitted to the Critical Care Unit. Shortly after admission she began to miscarry and rapidly developed septic shock and multiple organ failure leading to death a few days later. Sputum samples subsequently grew streptococcus pneumoniae.

Despite clear evidence of a severe systemic infection, none of the medical staff initially involved in this woman’s care appreciated just how sick she really was; antibiotics were started late and senior staff were either not involved in her care at an early enough stage or also failed to appreciate the severity of her illness.

Box 19.1

Critical care learning points: identifying very sick women

The recognition of life threatening illness is challenging.

Physiological reserves increase in pregnancy and may further conceal the development of serious pathology.

Modified early warning scoring systems

The well recognised problems of recognising life threatening illness has led to the introduction of a number of early warning scoring systems (EWS), also known as patient at risk scores (PARS) or modified early warning scores (MEWS)6. An EWS is calculated for a patient using five simple physiological variables: Mental response, pulse rate, systolic blood pressure, respiratory rate and temperature. For patients who are postoperative or unwell enough to be catheterised a sixth variable, urine output can also be added. The principle is that small changes in these five variables combined will be seen earlier using EWS than waiting for obvious changes in individual variables such as a marked drop in systolic blood pressure which is often a pre-terminal event. Of all the variables, respiratory rate is the most important for assessing the clinical state of a patient but is the one that is least recorded. Respiratory rate is thought to be the most sensitive indicatory of a patient’s physiological well-being. The changes in physiology seen in normal pregnancy mean that any scoring system may need to be modified for this group of patients as pregnancy progresses. The poor calibration of scoring systems for obstetric admissions supports this theory2 but does mean that the error will be on the safe side, i.e. mothers will be referred earlier than may be necessary.

Modified early obstetric warning scoring system (MEOWS)

Some units have produced their own scoring systems modified for obstetric patients and the one reproduced in the Annex to this Chapter has been developed by Aberdeen Maternity Hospital and is reproduced with their kind consent.

Box 19.2

Critical Care learning points: early warning scores

Modified early warning scoring systems improve the detection of life threatening illness.

Some modification of the physiological limits set may be required later in pregnancy.

However, the detection of life threatening illness alone is of little value. It is the subsequent management that will alter the outcome.

On their own, though, MEOWS can only be part of the solution, as it is the response to the abnormal score that will determine any real change in outcome:

A woman was admitted with a diagnosis of ovarian hyper-stimulation syndrome (OHHS), and was pyrexial and tachycardic on admission. A couple of days later she was short of breath at rest with pulse oximeter saturations of 89%, a blood pressure recorded as 146/34 mm/Hg and a reduced urine output. She was found to have bilateral effusions and ascites. The nursing staff placed her under increased observations and used a MEWS chart. Critical care referral and blood gas analysis were suggested to the junior medical staff who decided to do neither. Shortly afterwards, with her decline carefully charted but no action taken, she had a pulse rate of 176 bpm and an un-recordable blood pressure. She died of her pneumonia on the Critical Care Unit.
Management of life-threatening illness
Haemorrhage

Examples of the poor management of haemorrhage in obstetric patients have been raised in this, and previous Reports. Obstetric haemorrhage continues as one of the major reasons for admission to Critical Care and so overall its management must be good if the low mortality amongst obstetric admissions is to be easily explained:

A woman suffered a postpartum haemorrhage after a normal vaginal delivery and, following an examination under anaesthesia, went on to have a hysterectomy during which her estimated blood loss was 3,000 mls. She received 1,000 mls of Hartmann’s solution, 1,000 mls of normal saline, 1,000 mls of a gelatine based plasma expander, six units of re-suspended red cells and 2 units of FFP. There was no Critical Care bed immediately available so anaesthesia was reversed and she was admitted to the high dependency unit (HDU). She remained tachycardic for the next four hours but maintained her blood pressure at 110/60 mm/Hg. Over the next few hours she became increasingly tachycardic up to 160bpm and hypotensive down to 90/28 mm/Hg. During this period she received a further seven units of re-suspended red cells, 1,000 mls of Normal Saline, two units of FFP, one pack of platelets and five units of cryoprecipitate. She was eventually admitted to Critical Care some hours after the end of her surgery where she was intubated and ventilated because of poor blood gases and appeared to develop a disseminated intravascular coagulopathy (DIC). She had a cardiac arrest some hours later and subsequently died.

There are lessons to be learnt from several aspects of this case. 3,000 mls is a major loss of blood during a hysterectomy and the junior staff involved should have asked for senior help earlier. Although her circulating volume was reasonably well replaced during surgery this was almost entirely with a mixture of red cells and saline with little or no appreciation that this would inevitable lead to a serious dilutional coagulopathy.

Recently the whole question of transfusion regimens for significant bleeding has been questioned. The American military have moved to using a ratio of one FFP to every unit of packed red cells and have apparently demonstrated an improvement in battlefield mortality. Using a pharmacokinetic model of clotting factor levels Ho et al7 concluded that in major haemorrhage the equivalent of whole-blood transfusion is required to prevent the development of a coagulopathy and whole blood transfusion remains a widely used practice in combat situations. The exact requirement for FFP replacement will never be known but the availability of increasingly reliable point-of-care testing devices for haemoglobin estimation and clotting tests will help in the management of bleeding patients.

Many units have massive transfusion protocols and these should be regularly reviewed as new evidence becomes available. Effective management requires experience, the ability to predict likely requirements, good communication with, and cooperation from, haematology and blood bank services and appropriate fluid delivery and warming equipment.

The management of massive obstetric haemorrhage is included in commercially available advanced life support courses8 although at present these are primarily directed at medical staff only. There is perhaps a need to develop a nationally approved, scenario based team training in the management of major obstetric haemorrhage that is available and affordable to all members of theatre, recovery and high dependency unit teams.

The delay in obtaining a critical care bed has been discussed before and overall the provision of critical care beds has improved since the last Report. Despite this, delays will on occasion be inevitable but are no excuse for poor quality care.

Box 19.3

Critical care learning points: haemorrhage

Massive haemorrhage protocols should be used early and adhered to.

The development of a dilutional coagulopathy should be avoided if at all possible by the early use of FFP and other blood products as required.

Teams should practice the management of massive haemorrhage on a regular basis.

Sepsis

Severe systemic sepsis especially when accompanied by septic shock remains a challenge to all those involved in the care of critically ill patients. The onset of severe sepsis can be alarmingly rapid and once established difficult to treat as demonstrated by the woman with streptococcal pneumonia discussed above. There were other cases reported where there were reasonably clear signs of severe sepsis which were initially ignored:

A woman presented at early in her third trimenster with a low grade pyrexia and contractions and was treated with ritodrine, steroids and augmentin. Her CRP level rose from 16 to 152 mg/l during the first day of her admission. She underwent a caesarean section under general anaesthesia. Her arterial saturations by pulse oximetry were 66% at the start of the procedure rising with an increase in inspired oxygen. Despite this she was extubated at the end of the procedure with saturations of 75-88% on eight litres per minute of oxygen by facemask. A blood gas taken at that time showed a base excess of -11.9 mmol/l. She was referred to the critical care team because of increasing shortness of breath before she was commenced on continuous positive airway pressure (CPAP). Due to a lack of beds she was transferred to the theatre recovery suite and was managed on CPAP with direct arterial pressure monitoring. She was eventually transferred to the Critical Care Unit a few hours post operatively where she steadily deteriorated and died some days later from severe acute respiratory distress syndrome (ARDS). Her blood cultures grew listeria.

While it is impossible to say whether earlier, more aggressive, intervention might have saved her, the development of such a severe metabolic acidosis early on in her treatment was indicative of septic shock.

Although our understanding of the complex processes underlying severe sepsis increases year on year, the search for “silver bullets” remains largely unproductive. Recently a different approach has been proposed with the introduction of the Surviving Sepsis Campaign9. This is an initiative of the European Society of Intensive Care Medicine, the International Sepsis Forum, and the Society of Critical Care Medicine, which has been developed to improve the management, diagnosis, and treatment of sepsis. The approach has been to develop evidence based guidelines, delivered as bundles of care, the first two bundles cover resuscitation and management of severe sepsis and are delivered as a continuum. The inclusion of a considerable quantity of locally dictated protocols supports the view that there remains uncertainty in some areas of care. The bundles of care proposed are reproduced in Box 19.4.

Box 19.4 Surviving sepsis campaign

Sepsis resuscitation bundle
Sepsis management bundle

Although at first sight these seem complex, and indeed the management bundle is applied differently from one unit to another, the resuscitation bundle is applicable to both ward and HDU based patients as well. The failure to respond to fluid resuscitation should trigger an urgent critical care referral.

The use of activated protein C is associated with an increase in bleeding in some groups of patients and trials in children have been halted. The balance of risks and benefits at present remains unclear.

Box 19.5

Critical care learning points: severe sepsis

Severe sepsis can develop quickly and when accompanied by septic shock kills previously fit women.

Serum lactate, blood gases and blood cultures should be measured early in suspected cases of systemic sepsis.

Fluid resuscitation should be prompt and the effect noted without delay.

Failure to respond to 20mls/kg of intravenous fluids should trigger an urgent critical care referral.

Resuscitation

In the majority of cases reviewed where cardiopulmonary resuscitation took place this was delivered to a very high standard and current advanced life support (ALS) guidelines were followed, although there were exceptions:

A woman had labour induced for post dates. This was accompanied by a marked rise in blood pressure, a sudden reduction in her conscious level and twitching of her limbs. Her observations were recorded as blood pressure 200/106 mm/Hg, pulse 20 bpm and saturations of 64% on 4 lpm of oxygen. An in-and-out urethral catheter was inserted following which her saturations fell and the on call anaesthetist was fast bleeped. An assisted delivery failed. Shortly afterwards her observations became unrecordable and an arrest call was put out. She was transferred to HDU with a blood pressure of 71/58 mm/Hg and saturations of 58%. Approximately an hour after her initial collapse she was transferred to the operating theatre for intubation and section, and subsequent transfer to a nearby Critical Care Unit. She died some days later and her autopsy showed a recent subarachnoid and mid brain haemorrhage.

Her intracerebral bleeds and subsequent death may have been unavoidable but the management of her airway, breathing and circulation was below an acceptable standard. A new ALS algorithm has recently been introduced and should be adopted in all clinical areas.

With the inevitable pressures to contain the costs of healthcare and the changes in working patterns amongst both junior and senior staff the attainment and renewal of appropriate resuscitation competencies is becoming a major challenge. A recent announcement10 by the Resuscitation Council (UK) states “We are investing considerable resources in the development of e-learning materials to enable resuscitation training to be delivered more efficiently and cost-effectively. This will reduce the time that NHS staff need to be away from their workplace. Training will remain standardised and the quality preserved.” This blended learning approach in which e-learning is combined with practical demonstrations and assessment should make the completion of nationally recognised ALS courses a more efficient process.

Box 19.6

Critical care learning points: staff training

All staff involved in the care of acute obstetric admissions should have current ALS or ILS certification.

The introduction of blending learning for ALS will improve its uptake.

Conclusions

Reviewing case after case of often previously fit young women who, despite critical care, have gone on to die is a sad and depressing process. It is all too easy with the knowledge of hindsight to criticise the care they received. Some would have died however excellent their care, some would not. The excellent survival rates for obstetric patients admitted to Critical Care Units supports the view that the vast majority of these sick women receive care of the highest quality. There are nevertheless important lessons to be learnt from those who did not survive. Many of these lessons and messages have been discussed before but there is clearly still room for improvement and complacency should be avoided.