Management of shock -Urgent resuscitation is needed to prevent the mother's condition deteriorating and causing irreversible damage. - Women who decline blood products must have their wishes respected and a treatment plan in case of haemorrhage should be discussed with them before labour

The priorities are to: 1 Call for help – Shock is a progressive condition and delay in correcting hypovolaemia can lead ultimately to maternal death. 2 Maintain the airway – if the mother is severely collapsed she should be turned on to her side and 40% oxygen administered at a rate of 4–6 L/min. If she is unconscious an airway should be inserted. 3 Replace fluids – two wide-bore intravenous cannulae should be inserted to enable fluids and drugs to be administered swiftly.

- Blood should be taken for cross-matching prior to commencing intravenous fluids. - A crystalloid solution such as Normal Saline, Hartmann's, or Ringer's lactate is given until the woman's condition has improved. -A systematic review of the evidence found that colloids were not associated with any difference in survival and were more expensive than crystalloids

-Crystalloids are, however, associated with loss of fluid to the tissues, and therefore to maintain the intravascular volume colloids are recommended after 2 L of crystalloid have been infused. -No more than 1000–1500 mL of colloid such as Gelofusine or Haemocel should be given in a 24 hrs period. -Packed red cells and fresh frozen plasma are infused when the condition of the woman is stable and these are available.

4 Warmth – it is important to keep the woman warm, but not overwarmed or warmed too quickly, as this will cause peripheral vasodilatation and result in hypotension. 5 Arrest haemorrhage – the source of the bleeding needs to be identified and stopped. Any underlying condition needs to be managed appropriately.

Assessment of clinical condition -An interprofessional team approach to management should be adopted to ensure that the correct level of expertise is available. -A clear protocol for the management of shock should be used, with the midwife fully aware of key personnel required. - Once the mother's immediate condition is stable, the midwife should continue to assess and record the woman's condition or liaise with staff on the intensive care unit if the woman is transferred.

-Hypovolaemic shock in pregnancy will reduce placental perfusion and oxygenation to the fetus. -This will result in fetal distress and possibly death. Where maternal shock is caused by antepartum factors, the midwife should determine whether the fetal heart is present, but as swift and aggressive treatment may be required to save the mother's life this should be the first priority.

-Detailed observation charts including fluid balance should be accurately maintained. -The extent of the mother's illness may require her transfer to a critical care unit.

Observations and clinical signs of deterioration in hypovolaemic shock 1 Assess level of consciousness in association with the Glasgow coma score. This is a reliable, objective tool for measuring coma, using eye opening, motor response and verbal response. A total of 15 points can be achieved, and one of <12 is cause for concern. Any signs of restlessness or confusion should be noted 2 Assess respiratory status using respiratory rate, depth and pattern, pulse oximetry and blood gases. Humidified oxygen should be used if oxygen therapy is to be maintained for some time.

3 Monitor blood pressure continuously, or at least every 30 min, with note taken of any drop in blood pressure. 4 Monitor cardiac rhythm continuously. 5 Measure urine output hourly, using an indwelling catheter. 6 Assess skin colour, core and peripheral temperature hourly. 7 If a CVP (central venous pressure) line has been sited, haemodynamic measures of pressure in the right atrium are taken to monitor infusion rate and quantities.

The fluid balance is maintained accurately 8 Observe for further bleeding, including lochia, or oozing from a wound or puncture sites. 9 Take blood for haemoglobin and haematocrit to assess the degree of blood loss. 10 The mother is likely to be nursed flat in the acute stages of shock. Clinical assessment will also include review of pressure areas, with positional changes made as necessary to prevent deteriorationA lateral tilt should be maintained to prevent aortacaval compression if a gravid uterus is likely to compress the major vessels .

Central venous pressure -Central venous pressure (CVP) is the pressure in the right atrium or superior vena cava. -It is an indicator of the volume of blood returning to the heart and reflects the competence of the heart as a pump and the peripheral vascular resistance. - In the presence of acute peripheral circulatory failure, which accompanies severe shock, the monitoring of CVP aids assessment of blood loss and indicates the fluid replacement required. - In such a situation it is extremely dangerous to base an intravenous regimen on guesswork. Hyper- or hypovolaemia, cardiac and renal failure may result.

Key points for hypovolaemic shock Call for help • Gain venous access and insert two wide-bore cannulae • Immediate rapid infusion of fluid is needed to correct loss • Identify the source of bleeding and control temporarily if necessary • Assess for coagulopathy and correct • Manage the underlying condition.

-The normal pressure varies between 5 and 10 cm H2O. -In shock the pressure will be persistently low (i.e. below 5 cm) and may even register a negative reading, indicating hypovolaemia. - The correct volume of replacement fluids may then be assessed with greater accuracy.

Method of measuring CVP -A catheter is inserted by a doctor (usually an anaesthetist) into a major vein such as the subclavian or external jugular vein and advanced into the right atrium. -The catheter is then connected to a manometer and an intravenous infusion using a three-way tap. -To take a manometer reading, the mother should be lying flat and the base of the manometer should be calibrated to measure 0 cm of water when aligned with the level of the right atrium

-This point is level with a mid-axillary line for most people -This point is level with a mid-axillary line for most people. The three-way tap is opened and filled with intravenous fluid. -The fluid will fall and rise with respiratory effort and should be allowed to stabilize before a reading is taken. - The highest level the fluid reaches is used for the CVP measurement. - Once the reading is completed the tap is returned to the infusion position.

A baseline observation is taken when the CVP catheter is inserted and the position in which the mother was lying is noted. -Minor changes in position should be noted, as they may alter the CVP reading.

Principles of care of CVP lines 1 Prevention of infection – insertion of the catheter requires strict asepsis. -The site should be inspected regularly for signs of infection and precautions taken to protect against inadvertent contamination during clinical procedures. 2 Maintaining a closed system – the mother will bleed profusely if the catheter becomes disconnected, or incur a possible air embolus.

-Connections in particular should be checked 3 Maintaining patency of the catheter by preventing clot formation – positive pressure of the infusion should be maintained. -Additional complications include pneumothorax, hydrothorax, trauma to lung or veins and cardiac arrhythmias during and due to insertion.