1. CALENTAMIENTO GLOBAL Y CONTAMINACIÓN ATMOSFÉRICA
1.1. BALANCE ENERGÉTICO DE LA TIERRA Y EFECTO INVERNADERO
1.1.1. EFECTO INVERNADERO
1.1.1.1. Gases de efecto invernadero (GEI)
nosebleeds, which occur at night.
The mother is concerned that her child might bleed to death. Can you assure her that this will not be the case?Nose: epistaxis 73
Key concepts
⦁ Epistaxis is commonly the result of a localized nasal condition. ⦁ Epistaxis may be caused by a systemic problem.
answers
Clinical cases
CASE2.1– Adult with nosebleed
A1: Whatisthelikelydifferentialdiagnosis?
Epistaxis can be due to a local condition or part of a systemic disease. Most cases are related to dilated vessels on the anterior septum, Little’s area, this is the region where the three different vascular supplies to the nose (sphenopalatine artery, ethmoid arteries and facial artery, via the superior labial artery) converge (Figure 2.1). Bleeding from Little’s area is especially common in younger adults; it occurs occasionally from the posterior nasal cavity, typically in elderly patients, and is usually related to a recent
upper respiratory tract infection or direct trauma (nose picking). A nasal tumour may present with unilateral epistaxis, although this is not profuse unless it erodes into an artery. The differential diagnosis of systemic diseases causing epistaxis includes any lesion that might interfere with coagulation, including diseases of the bone marrow and liver, and drugs that interact with the clotting cascade.
A2: Whatadditionalfeaturesinthehistorywouldyouliketoelicit?
Ask about a history of bruising or bleeding elsewhere, as this may indicate a bleeding diathesis. A full general medical history should be taken on any patient who presents with epistaxis once the condition has been treated, with particular reference to diseases (liver dysfunction) or therapies (antiplatelet agents, aspirin or warfarin) that may interfere with clotting.
A3: Whataretheimportantfindingsonexamination?
Primary resuscitation measures involve assessing the degree of blood loss and the need for intravenous fluids. Pulse and blood pressure should be checked and aid in determining whether the patient is in shock. The anterior nasal cavity should be examined to determine whether a bleeding point is visible, and if it is, this can be cauterized.
Bony nasal rim Little’s area
Anterior ethmoid artery
Superior labial artery
Posterior ethmoid artery Sphenopalatine artery
Nose: epistaxis 75
A4: Whatinvestigationswouldbemosthelpfulandwhy?
Investigations are undertaken after the patient has been assessed and active bleeding stopped if he or she is admitted to hospital. A full blood count (FBC) should be undertaken at the time of bleeding. A clotting screen should be performed to see whether the patient is over-anticoagulated or has a bleeding diathesis.
A5: Whatarethetreatmentoptions?
Priority is to arrest haemorrhage and resuscitate a shocked patient. Initial management follows an escalating scale of interventions, stopping only once the haemorrhage has arrested. Primary management involves squeezing the anterior cartilaginous nose for 10 minutes (Figure 2.2), tamponading the vessels of the anterior septum, with the patient in a head-down, seated position (ensuring ongoing epistaxis does not travel to the nasopharynx and on the pharynx and larynx). This simple measure will stop most nosebleeds. Visual inspection of the anterior nose will permit cauterization of the offending vessels. If this measure fails then nasal packing is required, and this can be performed with a variety of substances, including BIPP (bismuth iodoform paraffin paste) or Merocel packs. Packing the nose is an uncomfortable procedure and should be undertaken under local
anaesthesia (Co-phenylcaine spray – 5 per cent aqueous solution of lignocaine and phenylephrine). If the patient has been over-anticoagulated, correction of this is typically required. If the pack remains in situ over 48 h antibiotic prophylaxis is required because a secondary sinusitis or toxic shock syndrome may develop. All patients with packing should be admitted to the hospital because hypoxia, confusion and inhalation of a pack may occur. Occasionally, operations are required if nasal packing is unsuccessful such as correction of septal displacement so that the nose can be packed very tightly under general anaesthesia or sphenopalatine artery ligation may be undertaken.
CASE2.2– Child with nosebleed
A1: Whatisthelikelydifferentialdiagnosis?
The differential diagnosis is the same as for Case 2.1. However, it is exceptionally rare for systemic disease to present with epistaxis in a child, although acute leukaemia may present in this way. The most common cause is dilated vessels in Little’s area where vessels from the internal (anterior and posterior ethmoid arteries) and external (sphenopalatine artery and facial artery) carotid arteries anastomose.
A2: Whatadditionalfeaturesinthehistorywouldyouliketoelicit?
Additional features in the history are those in Case 2.1. Bruising and other bleeding problems should always be asked about in children with epistaxis. A full history of nasal symptoms such as crusting of the anterior nose should also be taken.
A3: Whataretheimportantfindingsonexamination?
Primary resuscitation measures involve assessing the degree of blood loss and the need for intravenous fluids, pulse and blood pressure should be checked and aid in determining whether the patient is in shock, although this is extremely unlikely in a child. The anterior nasal cavity should be examined to determine whether a bleeding point is visible, and if it is, this can be cauterized.
A4: Whatinvestigationswouldbemosthelpfulandwhy?
Unless systemic disease is suspected, no investigations are required. Occasionally, an FBC is needed if the patient has bled actively and often; however, anaemia is very rare from epistaxis in children.
A5: Whatarethetreatmentoptions?
The treatment in children is slightly different from that in an adult as the cause in a child is often vestibulitis resulting from frequent nose picking. This causes direct trauma to Little’s area. A course of Naseptin cream (chlorhexidine hydrochloride and neomycin) to the anterior nasal vestibule on both sides may settle any infection and resolve the condition as the child then picks the nose less frequently. Simple cautery with silver nitrate is effective in over half the cases, and can be undertaken with or without local anaesthesia. If the child is under 5 years old, it is better to perform cautery under general anaesthesia, primarily to keep the child still, to ensure it can be completed effectively. Randomized controlled trials demonstrate an equivalent efficacy for cautery and Naseptin. Parents should be warned that children with epistaxis tend to get further bleeding in half of all cases.
Nose: epistaxis 77