div class=”ChapterContextInformation”>
54. Shock in Obstetrics
Types
- 1.
Hypovolaemic—due to body fluid or blood loss
- 2.
Cardiogenic—direct damage to the heart
- 3.
Extracardiac obstructive—obstruction to blood flow
- 4.
Distributive—abnormal distribution of blood flow
Haemorrhagic shock (most common):
- (a)
Haemorrhage in antenatal period during the first trimester
- (b)
Antepartum haemorrhage
- (c)
Postpartum haemorrhage
Neurogenic shock:
- (a)
Ruptured ectopic pregnancy.
- (b)
Concealed intrauterine haemorrhage.
- (c)
Forceps delivery or breech delivery in incompletely dilated cervix.
- (d)
During internal version of foetus.
- (e)
Crédé’s method.
- (f)
Uterine rupture.
- (g)
Uterine inversion.
- (h)
Splanchnic shock—Seen due to accumulation of blood in splanchnic area after sudden emptying of the uterine cavity, e.g. rupture of membranes in a patient of polyhydramnios.
Cardiogenic shock: It is observed in conditions in which cardiac myocytes are unable to generate adequate stroke volume due to lack of efficient contraction, myocardial infarction and cardiac failure.
Endotoxic shock: It occurs due to toxins that precipitate vascular disturbance.
Other causes:
- (a)
Embolism: amniotic fluid, air or thrombus
- (b)
Mendelson’s syndrome
Note: A patient can present with shock due to multifactorial aetiologies, e.g. incomplete abortion leading to haemorrhagic and endotoxic shock, whereas ruptured ectopic and uterine rupture eventually lead to haemorrhagic and neurogenic shock.
Categories of shock
Category | Whole blood volume loss % | Pathophysiology |
|---|---|---|
Mild (compensated) | <20% | Peripheral vasoconstriction to preserve cerebral and coronary blood flow |
Moderate | 20–40% | Decreased perfusion of kidneys, intestine and pancreas |
Severe (uncompensated) | >40% | Decreased coronary and cerebral perfusion |
Advanced trauma life support (ATLS) classification of shock
Class 1 | Class 2 | Class 3 | Class 4 | |
|---|---|---|---|---|
Blood loss (%) | <15 | 15–30 | 30–40 | >40 |
Heart rate (beats/min) | <100 | >100 | >120 | >140 |
Systolic blood pressure (mmHg) | Normal | Normal | Decreased | Decreased |
Pulse pressure | Normal or increased | Decreased | Decreased | Decreased |
Respiratory rate (breaths/min) | 14–20 | 20–30 | 30–40 | >35 |
Mental state | Slightly anxious | Mildly anxious | Anxious, confused | Confused, lethargic |
Measurement of surgical blood loss: Anaesthesiologists and obstetricians frequently underestimate blood loss. Massive blood loss leads to errors in judgement of estimation, which is responsible for inadequate replacement of intravascular volume. The young patients exhibit signs of hypotension and tachycardia after significant haemorrhage has already taken place. Haemodynamic management requires continuous assessment of patient status by clinical assessment, by classical monitoring equipment and by microprocessor-enabled monitors like Flotrac Vigileo™. The blood loss measurement can be done by the following methods:
Visual assessment:
Direct measurement of blood collected in calibrated drapes.
Estimation of blood:
Fully soaked 4″ × 4″ sponge contains approximately 10 mL of blood.
Soaked laparotomy pads contain 100–150 mL of blood.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
