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Managing emergencies 

Managing emergencies
Managing emergencies

Heather Baid

, Fiona Creed

, and Jessica Hargreaves

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date: 09 May 2021

Cardiac arrest and advanced life support

Cardiac arrest is defined as the absence or severe reduction of cardiac output, resulting in inadequate perfusion of vital organs.

Cardiac arrests are rarely unforeseen, and the evidence suggests that patients normally exhibit one or more signs of physiological deterioration in the hours prior to arrest.1 Clinical indicators of potential deterioration are listed in Box 15.1, and it is important that the critical care nurse is responsive to these.

The incidence of cardiac arrest in critical care is increased because of the acuity levels of this patient group. There are many factors that can cause a sudden deterioration in the patient’s condition. The causes of cardiac arrest are manifold, and the common causes are listed in Table 15.1.

Table 15.1 Common causes of cardiac arrest


Potential causes


  • Myocardial infarction

  • Heart failure

  • Dysrhythmia

  • Coronary artery spasms

  • Cardiac tamponade


  • Respiratory failure

  • Respiratory depression

  • Airway obstruction

  • Impaired gaseous exchange


  • Hyperkalaemia

  • Hypokalaemia

  • Hypomagnesaemia

  • Hypercalcaemia

  • Hypocalcaemia

Treatment causes

  • Pulmonary artery catheterization

  • Cardiac catheterization

  • Surgery

  • Side effects of medications

Cardiac arrest is associated with the following dysrhythmias:

  • ventricular fibrillation (VF)

  • ventricular tachycardia (VT)

  • pulseless electrical activity (PEA)

  • asystole.

The Resuscitation Council (UK) publishes guidelines pertaining to CPR recommendations, which are available on its website.2 It is essential that critical care nurses regularly update their knowledge of these, as recommendations change in line with additions to the current evidence base.

The advanced life support (ALS) guidelines3 note the following:

  • the need to maintain minimally interrupted chest compressions

  • reduced importance given to the role of the precordial thump

  • delivery of drugs via the endotracheal route is no longer recommended

  • changes in timing of the first dose of adrenaline when treating VF/VT

  • atropine is no longer recommended for routine use in asystole or PEA

  • capnography is recommended to confirm and monitor endotracheal tube (ETT) placement and to monitor the effectiveness of CPR

  • recommendations for post-resuscitation care are also provided.

The ALS algorithm (see Figure 15.1) highlights the need to:

  • summon immediate help

  • begin CPR as early as possible in a ratio of 30:2

  • minimize interruptions to chest compression.

Figure 15.1 Adult advanced life support (ALS) guidelines for resuscitation.3 VF, ventricular fibrillation; VT, ventricular tachycardia; PEA, pulseless electrical activity. (Reproduced with the kind permission of the Resuscitation Council (UK).)

Figure 15.1 Adult advanced life support (ALS) guidelines for resuscitation.3 VF, ventricular fibrillation; VT, ventricular tachycardia; PEA, pulseless electrical activity. (Reproduced with the kind permission of the Resuscitation Council (UK).)

Two different pathways are identified for ALS:

  • a pathway for shockable rhythms (VT and VF)

  • a pathway for non-shockable rhythms (asystole and PEA).

Potentially reversible causes

It is useful to consider causes or aggravating factors during cardiac arrest. As an aid to memory these have been divided into two groups of four.

4 H’s

  • Hypoxia—check air entry, provide 100% oxygen, check that ETT is not misplaced.

  • Hypovolaemia—check for signs of haemorrhage, restore intravascular volume, determine the cause of hypovolaemia if present, consider surgical intervention.

  • Hyperkalaemia, hypokalaemia, hypocalcaemia, acidaemia, and other metabolic disorders—check blood results , review patient history for causes of electrolyte imbalance.

  • Hypothermia—suspect if near drowning, check with low-reading thermometer, consider rewarming.

4 T’s

  • Tension pneumothorax—diagnosis is normally made by clinical examination and ultrasound. It requires decompression with needle thoracocentesis followed by chest drain insertion.

  • Tamponade—consider causes (e.g. trauma, recent cardiac surgery). Tamponade may be present if distended neck veins are present. It requires an ECG, and thoracotomy may be necessary.

  • Toxic substances—consider the likelihood of accidental or deliberate ingestion of toxins. A drug screen is required. Consider antidotes if appropriate.

  • Thromboembolism—most commonly massive pulmonary embolism. Consider the need for thrombolysis.

Drugs that may be administered


This should be administered after the third shock in shockable rhythms and repeated every 3–5 min. In non-shockable rhythms, adrenaline should be administered once access is gained, and given every 3–5 min thereafter. CPR should not be stopped to allow the administration of drugs.

Anti-arrhythmic medication

There is little evidence to support their effectiveness, but medical staff may use various anti-arrhythmic medications for the management of arrhythmias in cardiac arrest.


This may be used for persistent VF or VT. The usual dose is 300 mg by a bolus injection. An infusion may follow the bolus. Consideration may also be given to the use of lidocaine, but not if the patient has already had amiodarone.


This may be administered for refractory VF if hypomagnesaemia is suspected. It is also useful in torsades de pointes or if digoxin toxicity is suspected.


This is not recommended routinely. Acidosis is better corrected by restoration of circulation. However, bicarbonate may be used if arrest is associated with hyperkalaemia or tricyclic antidepressant overdose.


This is recommended only if specifically indicated (e.g. in arrests caused by hyperkalaemia, hypocalcaemia, or overdose of calcium-channel-blocking medications).

Use of mechanical CPR aids

Prolonged cardiac compression can be extremely tiring, and rescuer fatigue can reduce the effectiveness of CPR. There are several ongoing trials exploring mechanical resuscitation aids. However, the Resuscitation Council (UK) has highlighted the need for further research before firm recommendations are made about their use.

Post-resuscitation care

Following successful resuscitation, correct management of post-resuscitation complications (post-cardiac arrest syndrome) is needed to enable complete recovery from cardiac arrest.

Post-cardiac arrest syndrome includes:

  • brain injury

  • myocardial dysfunction

  • ischaemia or reperfusion response

  • persistence of existing pathology.

Various recommendations have been made for improving the outcome of patients after cardiac arrest. These include the following:

  • Effective oxygenation. Maintenance of normal O2 and CO2 levels is recommended. The use of end-tidal CO2 monitoring is encouraged.

  • Effective circulatory support. Early PCI is recommended if cardiac arrest is related to STEMI. Otherwise supportive measures to maintain cardiac output (fluids and vasoactive drugs) are needed. An intra-aortic balloon pump may be required if conservative measures do not work.

  • Control of seizures. Seizures will occur in 5–15% of patients. These should be controlled with anticonvulsant drugs or barbiturates. There is no direct recommendation that prophylactic anticonvulsants should be used.

  • Glucose control. Hypoglycaemia should be avoided. Current recommendations are to maintain the glucose level at 10 mmol/L, but tight glycaemic control is not recommended after cardiac arrest because of the risk of hypoglycaemia.

  • Temperature control. Pyrexia should be avoided, and treatment of post-arrest hyperpyrexia may require antipyretics or active cooling measures.

Therapeutic hypothermia

The evidence suggests that therapeutic hypothermia may be beneficial post cardiac arrest, as it decreases the cerebral oxygen requirement and may inhibit the release of excitory amino acids and free radicals. It may also have a role in reducing the post-arrest inflammatory response.

Therapeutic hypothermia consists of three basic stages:

  • Induction. This involves cooling the patient using cooled fluid infusions, cooling blankets, gel pads, or a bypass machine. The body temperature is usually lowered to 32–34°C.

  • Maintenance. Fluctuation of temperature is best avoided during this stage, so it is suggested that cooling devices that measure and regulate temperature are best suited to this stage.

  • Rewarming. This should be achieved slowly, and current recommendations are to increase body temperature by 0.25–0.5°C per hour.

It is important to remember that hypothermia has associated risks (e.g. cardiac arrhythmia, coagulopathies, etc.). Therefore careful monitoring for side effects of hypothermia is required.


1 Morton PG and Fontaine DK. Critical Care Nursing: a holistic approach, 10th edn. Lippincott Williams & Wilkins: Philadelphia, PA, 2012.Find this resource:

2 Resuscitation Council (UK). Managing

3 Resuscitation Council (UK). Resuscitation Guidelines. Managing


Anaphylaxis is defined as a severe, life-threatening, generalized hypersensitivity reaction.4 It is characterized by life-threatening changes in the airway, breathing, and circulation, which may include the following:


  • Airway obstruction.

  • Pharyngeal and laryngeal oedema.

  • Hoarseness of voice.

  • Stridor.


  • Cessation of breathing.

  • Shortness of breath.

  • Wheeze.

  • Increased tiredness and workload of breathing.

  • Hypoxia.

  • Cyanosis.


  • Cardiac arrest.

  • Signs of shock.

  • Tachycardia.

  • Hypotension.

The Resuscitation Council (UK)5 and NICE4 have both highlighted difficulties in diagnosing anaphylaxis correctly, and suggest that anaphylaxis is a likely diagnosis if the patient presents with:

  • a sudden onset and rapid progression of symptoms

  • life-threatening airway, breathing, and/or circulatory problems

  • skin and mucosal changes (flushing, urticarial rash, erythema, angioedema).

However, it is important to note that in some patients changes may not be overt, and they may simply have severe hypotension without mucosal or skin changes. In addition, some patients may also present with abdominal symptoms (e.g. vomiting, abdominal pain, incontinence).

Anaphylaxis can be immunoglobulin E mediated, non-immunoglobulin E mediated (anaphylactoid), or idiopathic.

  • IgE-mediated reactions occur as a result of a previous exposure to an antigen. The immune system develops a immune response to that antigen that triggers the release of the chemical mediators that initiate anaphylaxis.

  • Non-IgE-mediated reactions occur without the presence of IgE antibodies, and can occur the first time that the patient is exposed to the antigen.

  • Idiopathic reactions—a large proportion of reactions can present as anaphylaxis, and the cause of the reaction is never determined.

Triggers of anaphylaxis

There are a plethora of causative factors. The evidence suggests that these vary with age. Generally, younger patients are more likely to have food allergies, whereas older patients may be more likely to react to medication. Virtually any food, medicine, or medicinal product can trigger an allergic reaction. Common allergens noted by the Resuscitation Council (UK)5 are listed in Box 15.2.

Management of the patient with anaphylaxis

Where possible the trigger should be removed. If the patient is receiving IV medications or IV infusions that may cause a reaction, these should be stopped immediately. Vomiting should not be induced if the allergy is thought to be a food allergy.

Other treatment should focus on assessing and managing the patient systematically. See Chapter 13 (Managing emergencies p. [link]) for a summary algorithm of the management of a severe anaphylactic reaction.


  • The patient should be assessed for signs of complete or partial airway obstruction. This requires immediate intervention, and specialist help should be sought.

  • The patient may require an artificial airway, and early intubation is recommended.

  • Emergency tracheostomy may be required if normal endotracheal intubation is not possible.


  • Respiratory function should be assessed.

  • If the patient is not breathing, ALS guidelines should be followed.

  • If the patient is breathing, they should be positioned in an upright position.

  • High-flow oxygen should be provided.

  • Nebulizers may be needed if the patient has bronchoconstriction.


  • Cardiovascular assessment should be undertaken.

  • If the patient has no cardiac output, ALS guidelines should be followed.

  • The patient’s position may need to be changed if they are hypotensive, so long as this does not affect respiratory function. A flat position with the legs elevated is recommended for hypotension.

  • IV access should be secured, preferably with a wide-bore cannula.

  • IV fluid challenge should be given (500–1000 mL of crystalloid is recommended).


  • Neurological function should be assessed using the AVPU or GCS score.

  • Pupil reactions should be assessed.

  • Blood glucose levels should be monitored.


  • Skin should be assessed for flushing, urticarial rash, and erythema.

  • The patient should be observed for signs of angio-oedema.

Medication for anaphylaxis

Several medications may be required. These include the following:


This is normally administered intramuscularly. Adrenaline may be administered intravenously (reduced dose), but only by specialist experienced medical staff. It is important to note that IV adrenaline in a patient with cardiac output can cause life-threatening cardiac arrhythmias, life-threatening hypertension, and severe myocardial ischaemia.


This can be given after the initial resuscitation. It may be administered intravenously or intramuscularly. Chlorpheniramine is normally the drug of choice.


These are given after the initial resuscitation. The drug normally given is hydrocortisone, and it may be administered intravenously or intramuscularly.


These may be given for bronchoconstriction. They can be administered by nebulizer (e.g. salbutamol, ipratropium) or they may be administered intravenously (e.g. aminophylline, magnesium). Note that magnesium is a vasodilator, so it may worsen hypotension.

Cardiac drugs

Adrenaline is the main cardiac drug administered, but other vasopressors, such as noradrenaline, may be needed, especially if the patient requires critical care admission. Glucagon can be useful if administered to patients who are receiving beta blockers. Some patients develop profound bradycardia, and atropine may be useful in the treatment of this.


Close monitoring of the patient is essential following management of a severe allergic reaction, as they may require transfer to critical care. In addition to monitoring, the patient may require:

  • timed blood tests (mast-cell tryptase may be helpful for confirming the diagnosis of anaphylaxis; it usually peaks 1–2 h after the onset of symptoms)

  • referral to an allergy specialist for testing.


4 National Institute for Health and Care Excellence (NICE). Anaphylaxis: assessment to confirm an anaphylactic episode and the decision to refer after emergency treatment for a suspected anaphylactic episode. CG134. NICE: London, 2011. Managing this resource:

5 Working Group of the Resuscitation Council (UK). Emergency Treatment of Anaphylactic Reactions: guidelines for healthcare providers. Resuscitation Council (UK): London, 2008.Find this resource:

Massive haemorrhage


Massive haemorrhage is defined as a situation in which a patient is bleeding uncontrollably and requires more than 10 units of red blood cells in a 24-h period. It is argued that this definition is difficult to apply in practice, so more specific definitions identify the following as signs of massive haemorrhage:

  • blood loss of > 150 mL/min

  • haemodynamic instability.

Massive haemorrhage may be associated with:

  • trauma (see Managing emergencies p. [link])

  • obstetric emergencies (see Managing emergencies p. [link])

  • gastrointestinal bleeds (see Managing emergencies p. [link]).

The mortality rate in this group of patients is as high as 50%, and therefore the early recognition of massive haemorrhage and correct management are important.

The use of massive transfusion protocols has been recommended for the correct management of this patient group. The UK blood transfusion and tissue transplantation services have published such protocols,6 and it is recommended that these are followed to enable timely and effective management of this patient group.

An ABC approach

Early involvement of the haematology department and/or consultant haematologist is recommended to ensure adequate provision of blood and blood products, rapid haematological blood results, and timely expert advice. This will need to be coordinated by a senior nurse or a doctor.

Treatment of the patient requires systematic assessment and management.


  • The patient’s ability to maintain an airway should be assessed.

  • If necessary, intubation should be considered.


  • High-flow oxygen should be administered if the patient is self-ventilating.

  • If the patient is being ventilated, normal blood gases should be maintained by adjustment of ventilation if necessary.

  • Respiratory assessment should be performed to assess the adequacy of ventilation.


  • The effects of blood loss should be monitored.

  • The target systolic blood pressure is 90–100 mmHg, or higher if clinically indicated (e.g. if trauma involves neurological damage).

  • Additional monitoring may be required.

  • Wide-bore cannulas should be inserted to facilitate the rapid administration of blood products as needed.

  • Bleeding should be arrested as soon as possible. This may require early surgical, radiological, or endoscopic intervention.

  • A tourniquet or pressure dressing should be used if external bleeding is apparent.

  • Resuscitation with fluids and blood should occur until haemostasis is secured. Blood and FFP should be transfused in accordance with massive haemorrhage guidelines, and 10 mL of blood products per kg is recommended. The timing will be dependent upon the severity of blood loss. See Managing emergencies p. [link] for principles of damage-control resuscitation with traumatic haemorrhage.

  • Cell salvage can be considered if appropriate.

  • Drugs to arrest bleeding should be administered following the manufacturer’s guidelines as clinically indicated (see Box 15.3).

  • Consideration may be given to the transfusion of other blood products, such as platelets, cryoprecipitate, and clotting factors.

  • Blood samples should be sent to the laboratory on initial presentation and throughout the resuscitation period to monitor the effects. The blood tests that are required are listed in Box 15.4.

  • Body temperature should be closely monitored and appropriate steps taken to avoid hypothermia (warming of replacement fluid, warming blankets, etc.).

  • Close monitoring for signs of adverse blood transfusion reactions is required.

  • Close monitoring of renal function and urine output is needed.

  • An accurate input/output fluid chart should be maintained.

Other considerations

Adverse complications of massive transfusion should be monitored for and treated promptly. Problems associated with massive haemorrhage are normally linked to fluid resuscitation attempts and the components of or chemicals used in stored blood. They include:

  • dilutional coagulopathies and DIC (see Managing emergencies p. [link])

  • hypothermia

  • electrolyte disturbances:

    • potassium

    • calcium

    • magnesium

  • transfusion reactions (see Managing emergencies p. [link]):

    • allergic

    • haemolytic

    • non-haemolytic

  • immunological reactions:

    • acute lung injury

    • immunosuppression

    • transfusion-related purpura

  • acidosis/alkalosis

  • air embolism.

Later problems include:

  • transfusion-related acute lung injury (see Managing emergencies p. [link])

  • non-cardiogenic pulmonary oedema

  • infection

  • multi-organ failure

  • death.


6 Joint United Kingdom Blood Transfusion and Tissue Transplantation Services Professional Advisory Committee (JPAC). Transfusion management of major haemorrhage. Managing emergencies

Further reading

Bird J. Massive blood transfusion for trauma patients. Emergency Nurse 2012; 20: 18–20.Find this resource:

Pham HP and Shaz BH. Update on massive transfusion. British Journal of Anaesthesia 2013; 111 (Suppl. 1): i71–82.Find this resource:

Preparing for health emergencies

The reorganization of healthcare provision following the Health and Social Care Act (2013) saw a contractual responsibility for NHS trusts to ensure robust and sustainable responses to emergency situations. NHS trusts therefore have a requirement to ensure appropriate Emergency Preparedness, Resilience and Response (EPRR).

A wide range of events can cause health emergencies and require the need for appropriate planning. These may include:

  • natural hazards

  • major accidents

  • outbreaks of disease

  • terrorist attacks.

The Department of Health has developed guidelines for responding to emergency situations for each part of the health sector.

Critical care units are guided by the NHS England document, Management of Surge and Escalation in Critical Care Services: standard operating procedure for adult critical care.7 (Separate guidance has been issued for critical care units that specialize in burns, paediatrics, and patients who require ECMO support.)

This document identifies changes that are required during periods of increasing demand for critical care beds, and includes provision for increasing demand during a ‘major incident.’ It emphasizes that during an emergency surge in demand for critical care beds, critical care units should act as a network, as it is unlikely that one unit would be able to offer sufficient beds to meet a rapid increase in demand.

The key aims of the guidance are:

  • to prevent mortality due to patients not being able to access critical care beds when these are required

  • to maximize capacity in a range of scenarios

  • to maximize capacity until all available resources are being utilized.

The guidance highlights the need for:

  • maintaining normal critical care services for as long as is reasonably practicable

  • equity of access and treatment for all patients

  • management of critical care resources across a network rather than one hospital.

During emergency surges in demand (such as those triggered by a major incident), critical care units will be expected to:

  • collectively deliver a 100% increase in Adult Level 3 Critical Care bed capacity (in response to either a ‘big bang’ or a ‘slow burn’ scenario)

  • assist other critical care units in the network to facilitate coping with the increase in demand for beds

  • identify non-critical-care-trained nursing staff to care for patients during an emergency surge in demand

  • increase capacity using a stepped approach as demand increases

  • be coordinated by local Critical Care Networks and by NHS England during a wider surge in demand

  • ensure that difficult decisions relating to access to critical care are made in conjunction with local critical care network policies rather than patient assessment criteria.

The guidelines highlight the need to continue to maintain ‘normal critical care services’ for as long as possible. However, in emergency situations they identify the need to potentially cancel elective critical care admissions. It is suggested that suspension of elective activity should occur in three stages:

  • Stage 1—cancellation of all elective, non-life-threatening, non-oncology surgery that requires critical care admission.

  • Stage 2—as for Stage 1, but also including cancellation of all non-life-threatening cardiac and general surgery that requires critical care admission.

  • Stage 3—as for Stages 1 and 2, but also including cancellation of all cardiac and oncology surgery.

Each NHS trust and critical care network should have local guidelines with regard to emergency preparedness, and it is important that these are available to the critical care team and that local training is provided.

If the incident is local in nature (e.g. a major road incident) it is likely to be managed by the critical care network. More widespread emergencies (e.g. an influenza pandemic) may require regional or national management.

In the event of an emergency situation it is likely that local guidelines will identify a coordinator to manage the emergency situation.

Critical care nurses will need to consider a number of practical points. These could include:

  • patient acuity levels of all patients in critical care beds within the critical care network

  • potential transfer of level 2 patients to another area (step down, HDU, etc.)

  • review of staff levels and staff skill mix

  • use of non-critical-care-trained nurses within the unit

  • availability of equipment

  • availability of pharmaceuticals

  • availability of support staff

  • availability of other consumables (e.g. sterile supplies).


7 NHS England. Management of Surge and Escalation in Critical Care Services: standard operating procedure for adult critical care. NHS England: London, 2013.Find this resource: