Maternal Sepsis

Sepsis is a condition where the body launches a large immune response to an infection, causing systemic inflammation and affecting the functioning of the organs of the body. It is a significant cause of maternal death.

Severe sepsis is when sepsis results in organ dysfunction, such as hypoxia, oliguria or raised lactate. Septic shock is defined when arterial blood pressure drops and results in organ hypo-perfusion.

Sepsis in pregnancy is a medical emergency that requires prompt recognition and management to reduce the risk of maternal and fetal morbidity and mortality.

Two key causes of sepsis in pregnancy are:

  • Chorioamnionitis
  • Urinary tract infections

 

Chorioamnionitis

Chorioamnionitis is an infection of the chorioamniotic membranes and amniotic fluid. Chorioamnionitis is a leading cause of maternal sepsis and a notable cause of maternal death (along with urinary tract infections). It usually occurs in later pregnancy and during labour.

Chorioamnionitis can be caused by a large variety of bacteria, including gram-positive bacteriagram-negative bacteria and anaerobes.

 

Presentation

All patients admitted to maternity inpatient units, such as at the antenatal ward and labour ward, will have monitoring on a MEOWS chart. MEOWS stands for maternity early obstetric warning system. This includes monitoring their physical observations to identify signs of sepsis.

The non-specific signs of sepsis include:

  • Fever
  • Tachycardia
  • Raised respiratory rate (often an early sign)
  • Reduced oxygen saturations
  • Low blood pressure
  • Altered consciousness
  • Reduced urine output
  • Raised white blood cells on a full blood count
  • Evidence of fetal compromise on a CTG

 

Additional signs and symptoms related to chorioamnionitis include:

  • Abdominal pain
  • Uterine tenderness
  • Vaginal discharge

 

Additional signs and symptoms related to a urinary tract infection include:

  • Dysuria
  • Urinary frequency
  • Suprapubic pain or discomfort
  • Renal angle pain (with pyelonephritis)
  • Vomiting (with pyelonephritis)

 

Investigations

Arrange blood tests for patients with suspected sepsis:

  • Full blood count to assess cell count including white cells and neutrophils
  • U&Es to assess kidney function and for acute kidney injury
  • LFTs to assess liver function and as a possible source of infection (e.g. acute cholecystitis)
  • CRP to assess inflammation
  • Clotting to assess for disseminated intravascular coagulopathy (DIC)
  • Blood cultures to assess for bacteraemia
  • Blood gas to assess lactate, pH and glucose

 

Additional investigations can be helpful based on the suspected source of infection:

  • Urine dipstick and culture
  • High vaginal swab
  • Throat swab
  • Sputum culture
  • Wound swab after procedures
  • Lumbar puncture for meningitis or encephalitis

 

Management

Senior obstetricians and midwives should be involved early in the care of women with suspected chorioamnionitis or sepsis. There should be a local guideline in your hospital for the management of maternal sepsis. Early recognition and management is essential. This will involve the septic six (see below).

Continuous maternal and fetal monitoring is required. Depending on the condition of the mother and fetus, early delivery may be needed. Emergency caesarean section may be indicated when there is fetal distress, guided by a senior obstetrician. General anaesthesia is usually required for women with sepsis, as spinal anaesthesia is avoided.

Always follow the local guidelines when choosing antibiotics. Very heavy-hitting antibiotics are required, needing to cover gram-positive, gram-negative and anaerobes. There are also significant consequences of inadequate treatment. Example regimes include piperacillin and tazobactam (tazocin) plus gentamicin, or amoxicillinclindamycin and gentamicin.

TOM TIP: When preparing for exams and thinking about possible antibiotic choices for different conditions, it is worth searching google for local NHS trust antibiotic policies. It is interesting to see how they vary between trusts, given the differences in antibiotic resistance in different locations. Think about what specific bacteria the microbiologists are targeting with varying choices of antibiotics. 

 

Septic Six

Three tests:

  • Blood lactate level
  • Blood cultures
  • Urine output

 

Three treatments:

  • Oxygen to maintain oxygen saturations 94-98%
  • Empirical broad-spectrum antibiotics
  • IV fluids