Severe sepsis in pregnancy
Sepsis is now the leading cause of direct maternal deaths in the UK, with a rate of 1.13 deaths per 100 000 maternities. There was a dramatic rise in this from the previous triennium (2003–2005) where it accounted for 0.85 deaths per 100 000 maternities. This is the first time that sepsis has been the leading cause of direct maternal death since reporting started in 1952. In the 2006–2008 CMACE report, sepsis accounted for a total of 29 deaths—26 direct and three late deaths. Group A β-haemolytic Streptococcus (GAS) was responsible for 13 of the deaths, Escherichia coli for five, and Staphylococcus aureus for three. GAS commonly causes sore throats and upper respiratory tract infections (URTIs).
The commonest sites of infection during pregnancy are the genital tract, urinary tract, breast, lung and skin and soft tissue. Many of the patients who died from GAS had reported a sore throat or had been in contact with children who had a throat infection. The diagnosis of sepsis in pregnancy may be difficult, as the signs and symptoms may be less distinctive. Important signs of sepsis that may be missed are diarrhoea and vomiting, constant abdominal pain, hypothermia, and leucopenia. Evidence of fetal distress or an absent fetal heart without placental abruption are also indicators of sepsis. This is because the uteroplacental circulation is not autoregulated, and thus fetal oxygenation is reliant on maternal oxygenation and cardiovascular stability.
1 Recognize the presenting features of sepsis in the parturient at term
2 Commence appropriate antimicrobial therapy
3 Recognize and manage DIC as a complication of sepsis in pregnancy.
2B05; 2B06
A 38-year-old lady from Ghana, parity 1 + 2, presents in the early hours of the morning at 36 + 3 weeks gestation with possible spontaneous rupture of membranes. She had a previous normal delivery in Ghana 12 years previously. This pregnancy has been uncomplicated. The patient has no other medical history, takes no regular medication, and has no allergies. She has no anaesthetic history and is a non-smoker.
The obstetricians perform a speculum examination of this lady and can see clear liquor draining from the cervix which is posterior. A high vaginal swab is taken. Fetal monitoring is reassuring with a reactive trace. However, there is no uterine activity on the CTG. She is allowed to go home with the advice to return the following day for induction if she fails to go into labour.
She re-attends, as advised, 24 hours later and is given a pessary to induce labour. She begins to contract, and, 12 hours later, she is 2–3 cm dilated. She is admitted to the labour ward, and baseline observations are performed. Her observations include: HR 105 bpm, BP 126/74 mmHg, temperature 38.4ºC, RR 21 breaths/min, and oxygen saturations 97% on air.
She is tachycardic, pyrexial, and tachypnoeic. There is evidence of sepsis, as she has three features of the SIRS, and the cause of this is likely to be secondary to infection from prolonged rupture of membranes.
Blood cultures, high vaginal swab, urine sample for microscopy and culture, FBC, U&E, coagulation, and blood group typing and saving of sample. An ABG analysis would also be appropriate, paying particular note to lactate and the base excess.
This lady requires broad-spectrum antibiotics. CMACE recommends IV co-amoxiclav or a third-generation cephalosporin, in addition to IV metronidazole.
She should be commenced on IV fluid therapy and catheterized, with hourly urine output monitoring. Paracetamol can be administered for its analgesic and antipyretic properties.
This lady is re-examined 4 hours later, and her cervix is now 4 cm dilated, with meconium-stained fluid discharge. The CTG shows a fetal tachycardia at 165 bpm. The maternal observations are: HR 110/min, BP 120/70 mmHg, temperature 38.0°C, and RR of 24 breaths/min. The obstetricians decide to commence a Syntocinon® infusion to augment the labour and plan to re-examine after 2 hours.
An hour later, there are signs of fetal distress on the CTG with late decelerations. The mother is re-examined, and her cervix is 6 cm dilated. Her tachycardia, tachypnoea, and pyrexia are worsening. Her blood results demonstrate a neutrophilia with a WCC of 25 × 109/mL. In view of the fetal distress, it is decided to perform a Caesarean section.
As this patient is septic, regional anaesthesia is relatively contraindicated, due to the risk of spinal abscess formation. This lady requires a general anaesthetic which proceeds with an uneventful induction. During the operative delivery, the obstetricians comment that there appears to be foul-smelling residue within the uterus.
Chorioamnionitis.
See Table 5.1.
Table 5.1 Obstetric and patient risk factors for peripartum sepsis
| Obstetric factors | Patient factors |
|---|---|
|
Prolonged spontaneous rupture of membranes |
Increased BMI |
|
Retained products of conception |
Diabetes/impaired glucose tolerance |
|
Amniocentesis |
Black |
|
Cervical cerclage |
Anaemia |
|
Prolonged labour with >5 vaginal examinations |
Vaginal discharge |
|
Impaired immunity |
|
|
History of pelvic infection |
|
|
History of GAS infections |
|
|
Poor socio-economic background |
Sepsis in pregnant women is often caused by more than one organism. The commonest pathogens are GAS (Streptococcus pyogenes) and Escherichia coli.
◆ Sepsis
◆ Secondary to Syntocinon® bolus
◆ Haemorrhage
◆ Embolus: either thromboembolic or amniotic fluid embolism
◆ Supraventricular tachycardia.
◆ Fluid resuscitation: the Surviving Sepsis campaign recommends 20 mL/kg fluid bolus of crystalloid or colloid
◆ Antimicrobials: as sepsis is the most likely cause, then consideration of broadening the antibiotic cover with piperacillin/tazobactam, meropenem, or ciprofloxacin and gentamicin. Clindamycin would be an option to cover GAS, as it is better for inhibiting exotoxin production by this organism, and metronidazole should be prescribed in all cases, if not already commenced for anaerobic cover. Teicoplanin or linezolid are recommended if methicillin-resistant Staphylococcus aureus (MRSA) is considered.
She remains hypotensive intraoperatively, with a BP of 75/30 mmHg and a tachycardia of 136 bpm. The patient had been catheterized at the start of the operation and had a residual of 50 mL. Her urine output during the past 30 min is 12 mL.
This patient has septic shock, as she is hypotensive.
◆ Senior help: if not already present, the consultant anaesthetist should be informed of the deterioration. She should be referred to intensive care for post-operative placement due to the potential for renal failure and progressive septic shock
◆ ABC management: the patient should remain intubated and further IV fluid boluses cautiously titrated against the response in BP, provided there is no evidence of pulmonary oedema. Boluses of vasopressors may be required, e.g. metaraminol which can be used safely as she is post-delivery
◆ An arterial line should be sited for BP monitoring and sampling. ABGs should be analysed for acidosis and to check oxygenation, lactate, and Hb. All bloods should be resampled, including coagulation, due to the risk of DIC developing. A CVC to monitor fluids and as the administration of vasopressors, e.g. noradrenaline, is likely to be required.
The Caesarean section is ongoing, and the estimated blood loss is at 1400 mL. The obstetricians comment that the patient is ‘oozy’. The midwife checks up the blood results taken prior to the start of surgery: Hb 82 g/L, WCC 27.5 × 109/L, Plt 53 × 109/L, APTT 66 s, APTT ratio 2.1, PT 30 s, INR 2.5, fibrinogen 0.3 g/L.
The patient is anaemic, and the Hb is likely to have dropped in view of the intraoperative blood loss. The WCC is elevated, and the patient has thrombocytopenia. The coagulation screen suggests the patient has developed DIC, resulting in increased blood loss at the surgical interface.
If not already present, the consultant anaesthetist should be in attendance. Senior obstetric support should be requested to ensure the optimal surgical techniques are being employed.
Blood products should be requested from the transfusion laboratory. An initial request of 2–4 U of red cells, 4 U of FFP, and a pool of platelets is an appropriate starting point. Cryoprecipitate may be given for the low fibrinogen level, although this may respond to FFP alone. The administration of further clotting factors should be guided ideally with frequent near-patient coagulation testing, if available, e.g. thromboelastography.
As a component of DIC, the patient is also likely to have hyperfibrinolysis which can be treated with IV tranexamic acid, usually 1 g as a loading dose, and then 0.5 g/hour as an infusion or a further 1 g 8 hours later.
This patient has septic shock, requiring vasopressors, which has been complicated by DIC and major obstetric haemorrhage. She should be kept intubated at this time to allow for a period of stability before considering extubation, and she should be transferred to the ICU for further care.
Summary
The RCOG guidelines recommend the need for a multidisciplinary approach to the management of sepsis and the use of early warning scoring systems. It advocated adhering to the Surviving Sepsis campaign guidelines of administration of broad-spectrum antibiotics within the first hour of recognition of sepsis after appropriate blood cultures, swabs, and samples have been taken. However, antibiotic administration should not be delayed if it is not feasible for these to be performed in a timely manner. As well as routine bloods, the measurement of serum lactate provides invaluable evidence of tissue perfusion and should be measured in cases where severe sepsis is suspected.