CHAPTER 3 Trauma 298 Phenol burns Phenol is absorbed through the skin and can cause renal failure. Water or sali ne soaks are contraindicated. Irrigation with copious running water is of benefit. Hydrofluoric acid burns Hydrofluoric acid causes intensely painful, deep burns. Treatment i s with copious irrigation with cold water followed by urgent transfer to hospital for calci um gluconate therapy. All rescue personnel must be protected from contact with the acid. Electrical injury Electrical injury may follow low or high tension current sources. Low ten sion characteristically produces small deep burns at entry and exit points with variable ti ssue damage between them. Depending on the anatomical path of conduction, there may be asso ciated cardiac dys- rhythmias. High tension burns from overhead cables may be associated wi th injuries due to a fall from a height. Ionizing radiation burns Burns from ionizing radiation are rare. They should be suspected i n any patient rescued from a fire at a nuclear installation. Treatment is with copious wate r irrigation using soap or detergent. It is essential that all rescue personnel avoid the possibility of contami- nation with radioactive materials. Flash burns Flash burns are caused by intense, very short exposure to severe heat, often pr oducing superficial or partial thickness burns. They may result from flame, radiation, or e xplosive burn injury. Normal clothing offers good protection against flash burns which are usually confined to exposed areas. Non-accidental injury (NAI) Non-accidental injury is most often seen in children, but may a lso occur in the elderly. Characteristic injuries include cigarette burns, scalds to the fe et and buttocks (from lowering into hot water), and burns with irons and other electrical a ppliances. Burn depth The anatomical depth of a burn can be divided into: - Simple erythema \200\224su perficial burn with no skin loss. Skin is red and tender and heals within 5 \200\22310 days with no scarring (typical of sunburn). Erythema is NOT included when counting burn area Superficial partial-thickness burns \200\224painful, with superficial blistering healing in 10 \200\22314 days. BURN INJURY1 299 Deep partial-thickness burns \200\224thick-walled blisters with a granular white skin and p inpoint red mottled areas. Associated pain may be limited because of damage to the skin adn exae. Deep full-thickness burns \200\224producing white leathery charred skin with no sensation. These burns commonly follow prolonged contact with a burning agent or dr y heat. Scarring is inevitable. Superficial partual-thickness burn Epidermis Germinal layer Deep partial-thockness burn Dermis Deep burn Subcutaneous fat Fig. 3.22 Anatomical diagram showing burn depths. Reprinted with permission from Greaves I et al. (2005). Emergency care: a textbook for paramedics, 2nd edn. W.B. Saunders Co. Ltd. CHAPTER 3 Trauma 300 Factors affecting the outcome of burns Extent of burns Surface area may be assessed using t he \200\230rule of nines \200\231 in adults or the \200\230rule of fives \200\231 in chil dren, for which standard assessment charts are available. The palm of the hand in adults (w ith the adducted fingers included) equates to approximately 1% body surface area. Assessmen t of the burns surface area is difficult in the pre-hospital environment and does not mater ially change management unless there is a significant transfer time to hospital. A simpler criteria is the \200\230rule of halves \200\231 using the following system: - Is over half of the patient burnt? - Is the area burnt between a fourth and a half of the patient \200 \231s skin surface area? Is the area between an eighth and a fourth of the patient \200\231s skin surface area? Is the area less than an eighth of the total skin surface area? A more detailed and accurat e assessment can be carried out after arrival in hospital. Burn site A poorer prognosis is associated with burns to the: - Face (often associated with smoke inhalation) - Hands or feet - Eyes - Ears - Perineum Burns involving these areas, ho wever small the surface area, require management in a specialist unit. Circumferential burns to the neck may produce airway compromise, to the chest, respiratory compromise, and to the limbs may be associated with limb ischaemia. There is no role for es charotomy in normal UK pre- hospital care practice although unusual circumstances may dicta te the need for local protocols. BURN INJURY1 301 15% 20% Front 20% 10% Back 20% Front 20% 10% 10% 10% Back 20% 10% 10% 15% 15% Child Infant Fig. 3.23 \200\230Rule of fives \200\231 (children and infants). The quoted percentages re fer to the front or back of the limbs, but to the whole of the head. Reprinted with permiss ion from Greaves et al. (2005). Emergency care: a textbook for paramedics, 2nd edn. W.B. Sa unders Co. Ltd. CHAPTER 3 Trauma 302 Inhalation injuries Inhalation injuries are a major cause of death due to: - Direct thermal injury by inhalation - Inhaled toxic substances - Systemic poisoning (for example, carbon monoxide) Age of the patient Mortality is increased in children under five years of age because child surface area is greater in relation to their total body size. The elderly are at risk because of poor healing potential and reduced physiological reserve. Associated injuries Causes of associated injury include: - Falls or jumps from a height in building fires - Impact injuries in road traffic accidents - Electrical injuries including arrythmias in electrocution Associated medical conditions Significant co-morbidities include ischaemic heart disease, d iabetes mellitis, steroid therapy, and immunocompromised patients. Immediate care of thermal injuries Scene safety - Ensure scene safety regarding avoidable r isks to carers. - Remove the patient from the heat source and extinguish flames, if necessary. Remove burnt and hot clothing. - Cool the burn area for up to 20 minutes. This should begin whilst waiting for evacuation and be continued during packaging and transfer. Primary survey - Determine mechanism of injury. - A Assess and open the airway, if necessar y. - B Assess breathing and ventilation and seek the signs and symptoms of smoke inhalation. Only in extreme circumstances should intubation be attempted in the field, in which case a smaller than normal endotracheal tube should be used. Wheezing should be managed by the adm inistration of nebulized salbutamol. If the airway is critically threatened, the two options are surgical airway formation or an esthesia and intubation. The former is safer in inexperienced hands (see page 178). BURN INJURY1 303 9% Front 18% 9% 9% Back 18% 1% 18% 18% Fig. 3.24 \200\230Rule of nines \200\231 (adults). The percentage on each limb refers to t he front or rear aspect. A burn to the whole of the head represents 9% total body surface a rea (TBSA). Reprinted with permission from Greaves I et al. (2005). Emergency care: a textb ook for paramedics, 2nd edn. W.B. Saunders Co. Ltd. CHAPTER 3 Trauma 304 C Assess the circulation An accurate assessment of pulse, blood pressure, and capillary ref ill and subsequent monitoring is important in critical burns (greater than 15% in an adult and greater than 10% in a child). Depending on the mechanism of injury, it is important not to assume that shock is due to burn fluid loss. Intravenous cannulation, if necessary, sho uld avoid the burn area. Fluid replacement with normal saline or Hartmann \200\231s solution can be commenced if the patient is cannulated but must be started for burns greater than a fourth of total body su rface area or if time to hospital is more than one hour from the time of injury. A guide fo r fluid volume replacement is: - Adults: 1000ml - 10 \200\22315-year-olds: 500ml - 5 \200 \22310-year-olds: 250ml - Under 5:20ml/kg body weight D Assess disability (neurological assessment) As a baseline, a simple AVPU assessment is un dertaken and pupillary size and response noted. All patients are at risk of hypothermia with protracted burn cooling, especially children a nd the elderly. It is important to cool the burn wound but warm the patient. Secondary survey A detailed secondary survey is normally performed after arrival in hospita l. In pre-hospital care, the following details should be ascertained, if possible: - Time o f the burn - Burning agent - Is the patient complaining of pain? - Has the patient jumped o r been involved in an explosion? - Was the patient in a confined space? - Has the patient l ost consciousness at any time? - A brief medical history; drug and allergy history Tetanus status of the patient Signs and symptoms of smoke inhalation - History of being confined with the fire in a close d space - History of unconsciousness at the time of the incident - Exposure to smoke or gas during the incident - Evidence of burns to the face - Singed nasal hair - Cough or carbona ceous sputum - Blistering or redness in the mouth - Evidence of laryngeal oedema (e.g. hoar seness, stridor). - Wheezing - Signs of airway obstruction or respiratory distress - Full-t hickness burns to the nasolabial area of the face or posterior pharyngeal swelling Signs of respiratory failure: the patient who is unable to speak owing to shortness of breath or exhaustion, or who is unconscious This page intentionally left blank CHAPTER 3 Trauma 306 Assessment and treatment of carbon monoxide poisoning Most burns patients from a fire in an enclosed space have inhaled carbon monoxide. - Signs and symptoms of mild intoxication inc lude lethargy, muscle weakness, headache, nausea, and vomiting. Signs and symptoms of severe carbon monoxide poisoning are; cyanosis, coma, pulmonary oedema, and dilated pupils. Pulse oximetry is unreliable as it will not detect the difference between carboxyhaemoglobi n and oxyhaemoglobin. The classic cherry red appearance is a rare and very late feature. Dressings For burns of surface area less than 10%, a clean dressing soaked in cold water or normal saline should be applied. This will reduce the pain and halt or slow the burning pr ocess. For burns over 10%, a sterile clean cloth or clingfilm \233\232 should be used. Reducing th e air current over the burn will reduce pain and wound contamination. It is important to av oid circumferential dressings and clingfilm should, therefore, be gently laid over the burn wound in over- lapping sheets. Clingfilm should not be used for chemical burns as this may worsen the burn effect. Analgesia The ideal analgesic for burns is morphine given intravenously in aliquots accordi ng to body weight and with an antiemetic. Intramuscular and subcutaneous analgesia should b e avoided in moderate or severe burns because of delayed absorption. Patient disposal Treatment should be given with the aim of reducing on-scene times and deli vering the patient to the appropriate treatment center. This will be the nearest appropriat e A&E department unless local protocols allow direct transportation to a burns facility. Chapter 4 307 Formulary Introduction 308 Adrenaline 309 Amiodarone 311 Aspirin 312 Atracurium 313 Atropine 314 Benz yl penicillin 315 Bupivacaine 316 Chlorpheniramine Ketamine 331 Lignocaine (lidocaine) 332 Magnesium 333 Methionine 334 Metoclopramide 335 Mid azolam 336 Morphine 337 Naloxone 338 Nitrous oxide/oxygen 50:50 (chlorphenamine) 317 (Entonox) 340 Ondansetron 341 Oxygen 342 Pancuronium 344 Paracetamol 345 Pethidine 346 Pril ocaine 347 Propofol 347 Rocuronium 347 Salbutamol 348 Suxamethonium 349 Syntocinon (oxytoci n) 350 Tenecteplase 351 Thiopentone 352 Tramadol 353 Vecuronium 354 Pediatric doses 356 Sal butamol 358 Compound analgesics 318 Cyclizine 319 Dextrose 320 Diamorphine 321 Diazepam 322 Diclofenac (Voltarol) 323 Etomidate 323 Fentanyl 324 Flumazenil 325 Frusemide (furosemide) 326 Glucagon 327 Glyceryl trinitrate 328 Hydrocortisone 329 Ibuprofen 330 CHAPTER 4 Formulary 308 Introduction This chapter describes the drugs most commonly used in pre-hospital care. As a result, it is restricted to indications which are likely to be encountered in the pre-hosp ital management of patients and only describes formulations which are used in these circums tances. For example, the use of oral amiodarone is not discussed, neither is the use of ora l steroids in the management of chronic inflammatory conditions, although intravenous stero ids in acute asthma and anaphylaxis are men- tioned. Only significant acute side-effects are listed. Details of minor and chronic side-effects c an be found in the British National Formulary. No attempt has been made to list every recor ded side-effect of each drug mentioned. Acute allergic reactions are possible with any drug, as a result they are not specifically listed under individual entries. Pediatric doses are given on pp.356 \200\2238. INTRODUCTION1 309 Adrenaline Description Vasoconstrictor sympathomimetic catecholamine. Presentation - 1 in 10,000, 10ml ampoule/pre-filled syringe1 - 1 in 1000, 1ml ampoule/pre-f illed syringe1 - Self-administration pens for patient \200\231s own use (Epipen , Anapen Effects Acts on adrenergic receptors to constrict peripheral blood vessels; may also stabi lize mast cell membranes. ). Indications - Cardiac arrest - Anaphylaxis. Dose - Cardiac arrest \200\224standard dose, 1mg (10ml, 1 in 10,000). - Acute anaphylaxis \200\2241ml, 1 in 1000 (1mg) by intramuscular or subcutaneous injection. In severe anaphyla xis with circulatory compromise, use 1 in 10,000 by slow intravenous injection, titrated to effect. Contraindications None. Side-effects Anxiety, tremor, tachycardia, headache, arrhythmias, cold peripheries, pulmona ry oedema, nausea and vomiting, sweating, dizziness. Notes Adrenaline may also be used combined with lignocaine to reduce bleeding from peripher al vessels. If used inappropriately (for example, in fingers), this can lead to ischaemia a nd tissue loss. The use of lignocaine with adrenaline is NOT recommended in pre-hospital ca re. Anaphylaxis patients on non-selective beta-blockers may not respond to adrenaline (but may develop severe hypertension); intravenous salbu- tamol may be required after arrival in hos pital. 1 Other size ampoules are available but do not represent \200\230standard \200\231 doses; only the above should be carried. CHAPTER 4 Formulary 310 Doses of IM adrenaline in anaphylaxis Age Dose Volume of 1 in 1000 1mg/ml Under 6 months 6 months \200\2236 years 6 \200\22312 years 12 years and over 50 g 120 g 250 g 500 g 0.05ml 0.12ml 0.25ml 0.5ml DRUGS1 311 drugs Amiodarone Description Class III anti-arrhythmic drug. Effects Inhibits the activity of peripheral vascular calcium channels and adrenergic recept ors, resulting in peripheral vasodilatation, and of cardiac calcium channels, causing slowi ng depolarization. Presentation 30mg/ml, 10ml ampoule for intravenous injection; also available as pre- filled syringe. Indications - VF or pulseless VT. - Amiodarone should not be used for the treatment of vent ricular and supraventricular arrythmias pre-hospital. Dose 300mg by slow intravenous injection (at least 3 minutes). Contraindications None in cardiac arrest situations. Side-effects Not applicable in cardiac arrest situations. CHAPTER 4 Formulary 312 Aspirin Description Irreversibly acetylates cyclo-oxygenase, the rate-limiting enzyme in th e arachidonic acid cascade. Presentation 300mg soluble tablets is recommended for use in acute coronary syndrome. Aspir in is not carried as an analgesic. Effects Aspirin inhibits the aggregation of platelets and platelet degranulation as well as decreasing localized vasoconstriction. Indications Secondary prevention of thrombotic cerebrovascular or cardiovascular disease. Dose 300mg soluble aspirin dispersed in water. Contraindications - Caution in asthma - Active peptic ulceration - Hemophilia and other ble eding disorders - Aspirin is contraindicated in children under 16 and during breast-feeding (Reye \200\231s syndrome). Side-effects Bronchospasm, gastrointestinal bleeding. DRUGS1 313 Atracurium See pp.385 \200\2236. CHAPTER 4 Formulary 314 Atropine Description A cholinergic antagonist (anticholinergic). Presentation - 600 g/ml, 1ml ampoules for injection (other strengths are available) - 100 g/ml, 5ml, 10ml, 30ml pre-filled syringes - Also available as 200 g/ml, 5ml pre-filled sy ringe; 300 g/ml, 10ml pre-filled syringe; and 600 g/ml, 1ml pre-filled syringe. Effects - Tachycardia, increased cardiac output, and increase in systemic blood pressure Drying of secretions - Prevention of bradycardia in response to intubation (spinal injuries ) - Pupillary dilatation. Indications - Non-VF cardiac arrest - Profound bradycardia with hypotension - Organophospha te poisoning (see p.442) - Pre-intubation prevention of bradycardia in spinal injuries. Dose - Cardiac arrest \200\2243mg iv stat - Bradycardia \200\224increments of 500ug or 600u g titrated to effect (maximum dose 3mg) Organophosphate poisoning \200\224(see p.442) - Pre-medication \200\224up to 600ug (childre n 20ug/kg, maximum 600ug). Contraindications - In cardiac arrest \200\224none - Other situations \200\224angle-closure glaucoma, myasthenia gravis. Side-effects Constipation, bradycardia, tachycardia, arrythmias, drying of secretions and d ry skin, urinary urgency and retention, pupillary dilatation with loss of visual acuity, fl ushing, confusion, nausea and vomiting, and dizziness (rare). DRUGS1 315 Benzyl penicillin Description Penicillin active against meningococcus. Presentation Benzyl penicillin sodium 600mg and 1.2g vials for intravenous or intra- muscul ar injection. Effects Benzyl penicillin (penicillin G) is active against pneumococcus, meningo- coccus, a nd many other streptococci. Indications Established or suspected bacterial meningitis. Dose Adult 1.2g (2.4g in established disease) by intravenous injection (pre- ferred) or int ramuscular injection Children Under 1: 300mg 1 \200\223years: 600mg 10 years and over: adul t dose. Contraindications Penicillin allergy. Side-effects Allergic reactions. Notes Following arrival in hospital and pending sensitivity results, a cepha- losporin is u sually added or substituted. CHAPTER 4 Formulary 316 Bupivacaine See p.392. DRUGS1 317 Chlorpheniramine (chlorphenamine) Description Sedating antihistamine. Presentation - 10mg/ml, 1ml ampoule for injection - 4mg tablets. Effects - Binds to H1 receptors decreasing histamine-induced vasodilation, oe- dema, and secretion Also has anticholinergic activity. Indications - Symptomatic relief of allergy - Treatment of anaphylaxis. Dose Oral dose \200\2244mg Intravenous (im/sc) dose \200\22410mg by SLOW injection; may be repeated once Children 1 month \200\2231 year: 250ug/kg 1 \200\22312 years: 200ug/kg or 1 \200\2235 years: 2.5 \200\2235mg 6 \200\22312 years: 5 \200\22310mg Contraindications Urinary retention, glaucoma (due to anticholinergic effects). Side-effects Drowsiness, stimulation (rare), urinary retention, dry mouth, blurred vision, dizziness, confusion. Notes - Injection may result in transient hypotension or CNS stimulation; intravenous injection should be slow. Chlorpheniramine may be given sc or im, however the intravenous route is preferred when par enteral administration is necessary. CHAPTER 4 Formulary 318 Compound analgesics Description Analgesics containing paracetamol and an opiate. Presentation There are very many proprietary compound analgesics. Immediate care practition ers should carry ONE of the following: - Co-codamol 30/500 (codeine 30mg, paracetamol 500mg ) - Co-dydramol (dihydrocodeine10mg, paracetamol 500mg) - Co-proxamol (dextropropoxyphene 3 2.5mg, paracetamol 325mg). Effects Combined effects of opiates and simple analgesics. Indications Moderate pain. Dose - 1 \200\2232 tablets every 4 \200\2236 hours, maximum 8 in 24 hours - Not recommended in children. Contraindications Constipation and confusion may occur, so use with care in the elderly. Notes Compound analgesic overdoses present with the features of opiate poisoning (reversibl e with naloxone) and, subsequently, of paracetamol poisoning. Such overdoses are unfortunat ely common. DRUGS1 319 Cyclizine Description An antihistamine. Presentation 50mg/ml, 1ml ampoule for intramuscular or intravenous injection. Effects Prevention or reduction of nausea and vomiting. Indications - Established nausea or vomiting - Prophylaxis of opiate-induced nausea and vom iting. Dose Cyclizine 50mg iv. Contraindications Cyclizine is not recommended in severe heart failure and may counteract t he beneficial cardiovascular effects of opiates. Side-effects Extrapyramidal effects. Notes - Cyclizine is available as a combined preparation with morphine, cyclimorph (morphine 10mg/cyclizine 50mg in 1ml). Its use is not recommended. The treatment for extrapyramidal effects is benztropine 1 \200\2232mg by intravenous or int ramuscular injection, or procyclidine 5 \200\22310mg by intramuscular or intravenous inject ion. Management of these symptoms should take place in hospital. CHAPTER 4 Formulary 320 Dextrose Description Solution of anhydrous glucose. Presentation - 5% solution, 500ml and 1000ml bags - 10% solution, 500ml bags Effects Elevation of blood glucose levels. Indications - Hypoglycaemia - Fluid replacement. Dose - Hypoglycaemia \200\22425 \200\22350ml 10% glucose by intravenous injection; Children: 10% glucose titrated to effect Fluid replacement \200\2245% glucose titrated to effect. Contraindications None. Side-effects Hyperglycaemia, venous irritation, and thrombophlebitis. DRUGS1 321 Diamorphine Description Opiate analgesic (heroin hydrochloride). Presentation Powder for reconstitution; 5mg and 10mg ampoules (larger dose ampoules are ava ilable). Effects - Binds to opiate receptors resulting in analgesia, euphoria, and respiratory depression Decreases pre- and after-load (central mechanism) and increases force of ventricular contraction and ejection fraction. Indications - Acute pain, especially from myocardial infarction - Acute pulmonary oedema. Dose Up to 5mg by slow intravenous injection (may be repeated). Contraindications - Acute respiratory depression - Care in head injury. Side-effects Respiratory depression, nausea and vomiting, drowsiness, hypotension, tachycar dia, pinpoint pupils. Notes Naloxone (Narcan ) must always be available if opiate analgesics are being used. CHAPTER 4 Formulary 322 Diazepam Description Sedative hypnotic benzodiazepine. Presentation - 5mg/ml, 2ml ampoule diazepam emulsion for intravenous injection \210\227 - 2 .5mg, 5mg, and 10mg rectal tubes. Effects Acts through membrane GABA receptors to stabilize membranes, pri- marily in the CNS , and reduce depolarization. Indications - Cessation of epileptic fits/febrile convulsions/poisoning-induced seizures Sedation and amnesia for clinical procedures - Co-administration with ketamine to reduce em ergence phenomena (not required in children). Dose - 10 \200\22320mg by slow intravenous injection in aliquots to effect - Rectally, 500 g/kg - Children Status epilepticus \200\224rectal: children over 10kg, 500 g/kg maximum 20mg; intravenous: 300 \200\223400 g/kg or 1mg per year of age. Contraindications - Pregnancy or lactation (not applicable in status epilepticus) - Respira tory depression. Side-effects - May cause respiratory depression and apnoea (facilities for ventilatory support must be available) Drowsiness, occasionally irritability, excitability and hallucinations (more common in elderly patients). \210\227 For intravenous use, diazepam should be given as the emulsion. Benzodiazepines ma y also be used as muscle relaxants: use as such is not appropriate in acute pre-hospital ca re. DRUGS1 323 Diclofenac (Voltarol) Description A non-steroidal anti-inflammatory drug Presentation - Tab lets/capsules 50mg (smaller dose tablets are available) - Suppositories 100mg (smaller supp ositories are available) - Voltarol for intramuscular injection 25mg/ml, 3ml ampoule. Effects Decreases pain and inflammation by the inhibition of the prostaglandin synthesis ca scade, primarily through the inhibition of cyclo-oxygenase. Indications Acute pain; effective in ureteric and billiary colic. Dose - Oral 50 \200\223100mg - Suppository 100mg - IM 75mg (repeated once after 30 minutes in ureteric colic). Contraindications - Caution in the elderly, acute renal, cardiac, or hepatic failure - Pept ic ulcer disease. Side-effects - No acute significant side-effects with single doses - Caution in the elderly , acute renal, cardiac, or hepatic failure. Etomidate See p.381. CHAPTER 4 Formulary 324 Fentanyl See p.368. DRUGS1 325 Flumazenil Description Specific antagonist at central benzodiazepine receptors. Presentation 100ug/ml, 5ml ampoule for intravenous injection. Effects Specific antagonism of benzodiazepines at central receptors. Indications Reversal of benzodiazepines following administration for anesthesia or sedation . Dose 200 g over 15 seconds followed by 100 g at one-minute intervals; usual dose 300 \200 \223600 g. Contraindications Life-threatening condition controlled by benzodiazepine. Side-effects If flumazenil is administered too rapidly, agitation, fear, and anxiety may oc cur. Transient tachycardia, bradycardia (including complete heart block), hypertension VT a nd, occasionally, convulsions are possible. Acute withdrawal, including fitting, may occur in patients addicted to benzodiazepines. Notes Flumazenil is not licensed for use in the treatment of benzodiazepine overdose. In th e majority of such cases, respiratory support is appropriate pending arrival in hospital ra ther than reversal at scene which may pre- cipitate the problems described above (see side- effects) and the patient \200\231s rapid departure from the scene. Flumazenil MUST NEVER be used in patients with a history of convulsions or who have also taken tricyclic antidepressants. Flumazenil has a relatively short half life and repeated doses may be necessary with some longer-acting benzodiazepines. Flumazenil IS NOT recommended for pre-hospital use. CHAPTER 4 Formulary 326 Frusemide (furosemide) Description A loop diuretic. Presentation 10mg/ml, 2ml and 5ml ampoules for intravenous injection. Effects Acts in the ascending limb of the loop of Henle to inhibit reabsorption of sodium a nd increase water loss. Indications Acute pulmonary oedema secondary to left ventricular failure. Dose Initial dose 20 \200\22350mg; larger doses may be required in severe LVF. Contraindications - Anuric renal failure - Prostatic hypertrophy (may precipitate acute ret ention). Side-effects No major side-effects in the acute pre-hospital situation. DRUGS1 327 Glucagon Description Polypeptide hormone. Presentation 1mg vial with pre-filled syringe (wa ter for injections) for reconstitution. Effects Glucagon increases plasma glucose by mobili zing glycogen stored in the liver. (See below.) Indications Acute hypoglycaemia. Dose - 1mg by subcutaneous, intramuscular, or intravenous injection - Children: under 8 years (or und er 25kg) 500 g over 8 years (or over 25kg) 1mg. Contraindications None. Side-effects Nausea, vomiting, abdominal pain, hypotension. Notes B ecause glucagon acts by mobilizing glycogen stored in the liver, it will be ineffective in hypoglycaemia associated with starvation, chronic alco- holism, and other states in which l iver glycogen stores are depleted. CHAPTER 4 Formulary 328 Glyceryl trinitrate Description A vasodilator acting predominantly on the venous system. Pr esentation - 400 g metered dose sublingual spray - 300 g, 500 g, and 600 g sublingual t ablets - slow-release preparations (including Suscard and Sustac ), various sizes up to 10mg. Effects Coronary vasodilatation, reduction of venous return and left ventricular work, inhi bition of platelet function (antithrombotic effect) via cGMP. Indications - Angina - Left ventricular failure. Dose - GTN - Angina (treatment of attack) \200\224sublingual 0.3 \200\2231mg (tablet or spr ay) - Acute LVF \200\2245mg slow release (can be repeated). Contraindications Hypotension, aortic or mitral stenosis. Side-effects Headache, flushing, dizziness, postural hypotension, tachycardia. DRUGS1 329 Hydrocortisone Description An adrenal glucocorticoid. Presentation 100mg vial for intramuscular or intravenous injection, may be supplied with or without ampoule of water for injections (2ml). Effects Glucocorticoids: - Decrease capillary permeability - Decrease release of histamine by mast cells - Inhibit macrophage phagocytosis - Inhibit antibody production by lymphocyte s Indications - Anaphylactic shock - Acute severe asthma. Dose - 100 \200\223200mg - Children: up to 1yr, 25mg; 1 \200\2235yrs, 50mg; 6 \200\22312yrs , 100mg. Contraindications None in anaphylaxis or acute severe asthma. Side-effects Nil acute. CHAPTER 4 Formulary 330 Ibuprofen Description Non-steroidal anti-inflammatory drug. Presentation - 200mg, 400mg, and 600mg tablets - Pediatric suspension 100mg/ml. Effects Decreases pain and inflammation by the inhibition of the prostaglandin synthesis ca scade, primarily through the inhibition of cyclo-oxygenase. Indications - Acute pain - Pyrexia in children. Dose - 400 \200\223600mg orally - Fever and pain in children: 3 \200\2236 months, 50mg* 6 months \200\2231 year, 50mg 1 \200\2233 years, 100mg 4 \200\223 6 years, 150mg 7 \200\2239 years, 200mg 10 \200\22312 years, 300mg (all doses three times d aily) Contraindications - Caution in the elderly, acute renal, cardiac, or hepatic failure - Cont raindicated in peptic ulcer disease. Side-effects No acute significant side-effects with single doses. Notes Various slow-release preparations are also available. Body weight over 5kg. DRUGS1 331 Ketamine Description A dissociative anesthetic/analgesic. Presentation 10mg/ml, 20ml vial for injection* 100mg/ml, 10ml vial for injection Effects Ketamine has the following features: - It is powerfully analgesic in subanaesthetic doses - Protective glottal reflexes are relatively preserved - It does not normally cause respiratory depression at conventional doses It has a long shelf life - It does not cause hypotension, but ketamine-induced hypertension makes it relatively contraindicated in head injury - It is relatively safe in patients with a full stomach. Indications - Pre-hospital anesthesia for extrication or short procedures - Analgesia. Dose - Anesthesia: intramuscular \200\2245 \200\22310mg/kg (provides 12 \200\22325 minutes of surgical anesthesia, effective after 4 \200\22315 minutes) Intravenous \200\2241 \200\2232mg/kg (provides 5 \200\22310 minutes of surgical anesthesia, effective after 2 \200\2237 minutes) Analgesia; ketamine is an effective analgesic when used in subanaes- thetic doses by either the intramuscular or intravenous route Repeat doses may be given as 10 \200\22320mg intravenously or 20 \200\22350mg intramuscularly. - Children: as above Contraindications - Hypertension - Head injury (relative, but consider clinical priorities) . Side-effects A significant proportion of patients suffer emergence hallucinations which can be very distressing. As a consequence, a benzodiazepine should also be administered to obl ate these symptoms. 50mg/ml is also available but NOT RECOMMENDED for pre-hospital use. CHAPTER 4 Formulary 332 Lignocaine (lidocaine) Description Class Ib anti-arrhythmic. Presentation Anti-arrythmic - Lignocaine hydrochloride 1% (10mg/ml), 10ml pre-filled syringe - Lignocaine hydrochloride 2 % (20mg/ml), 5ml pre-filled syringe Local anesthesia - Lignocaine hydrochloride 1% (10mg/ml), 2ml, 5ml, and 10ml ampoules for injection Lignocaine hydrochloride 2% (20mg/ml), 2ml and 5ml ampoules for injection. Effects Lignocaine blocks sodium channels, reducing the conduction rate and amplitude of ne rve electrical impulses. Indications - Ventricular arrhythmias - Painful localized patholog y - Local anesthesia for painful procedures. Dose - Ventricular arrhythmias: 100mg by slow intravenous bolus (dose may be reduced in smaller patients) - Local anesthesia: see notes below - Children (local anest hesia): 3mg/kg. Contraindications - Anti-arrhythmic therapy: sino-atrial disorders, atrio-v entricular block. - Local analgesia: hypovolaemia, complete heart block. - Solutions with a drenaline: see notes below. Side-effects - These are rare with single applications of topic al lignocaine. - Inebriation and lightheadedness followed by sedation, circumoral paraesthesia, and twitching; convulsions in severe cases. Convulsions and cardiovascular collapse on intravenous administration. Notes 0.5% lignocain e is available for local anesthetic use. It is NOT recom- mended in the pre-hospital enviro nment. A MAXIMUM safe lignocaine dose for an average adult is 20ml of 1% (200mg) or equivalent vol ume of higher concentration solution. This dose can be increased if lignocaine is given wit h a vasoconstrictor such as adrenaline. Use of lignocaine with adrenaline may cause gangren e if injected into digits or appendages and is NOT RECOMMENDED in pre-hospital care. DRUGS1 333 Magnesium Description Administered as magnesium sulfate. Presentation Magnesium sulfate 50% \210\227, 2ml (1g) and 10ml (5g) ampoules, 10ml pre- filled syringe. Effects Precise mecha nism not known; effective in acute severe asthma. Indications - Acute severe asthma - Ventr icular tachycardia - Torsade de pointes. Dose - Asthma: 1.2 \200\2232g iv over 20 minutes - VT, torsade de pointes, and refractory VF: 8mmoles (4ml or 2g) over 30 minutes (followed by infusion after arrival in hospital). Contraindications None. Side-effects Symptoms of hypermagnesaemia: nausea, vomiting, flushi ng, hypotension, arrhythmias, respiratory depression, drowsiness, and confusion. Notes The dose of magnesium given above for the treatment of asthma should only be given ONCE to avoid symptomatic hypermagnesaemia. \210\227 1ml of 50% magnesium contains 2mmol magnesium. 20% magnesium sulfate is also avai lable (0.8mmol/ml). CHAPTER 4 Formulary 334 Methionine Description Paracetamol antidote. Presentation 250mg tablets. Indications The fi rst-line treatment for paracetamol overdose is N-acetylcysteine after arrival in hospital a nd within four hours of the overdose. Methionine is only indicated (and need only be carrie d) in areas in which prompt evacuation is likely to be impossible. Dose - Adult and child o ver 6: 2.5g initially followed by three further doses of 2.5g every 4 hours orally. Child under 6: 1g initially followed by three further doses of 1g orally. Contraindications Since it is given orally, methionine is ineffective in patients who are vomiting. Side-eff ects Nausea, vomiting, drowsiness, irritability. DRUGS1 335 Metoclopramide Description Prokinetic antiemetic. Presentation 5mg/ml, 2ml (10mg) ampoule for injection. Effects Antiemesis by central antagonism of dopamine. Cholinergic effects on the gut includ e increased gastric emptying, pyloric sphincter relaxation, increased lower oesophageal sph incter tone, and stimulation of peristalsis. Indications - Nausea and vomiting - Adjunct treatment with opiate analgesics. Dose 10mg by iv injection (may also be given im). Contraindications Not to be used in patients UNDER 20 YEARS OLD due to an increased risk of acute dystonic reactions. Side-effects Extrapyramidal effects (dystonia). Other side-effects are rare. Notes The treatment for extrapyramidal effects is benztropine 1 \200\2232mg by iv or im inj ection or procyclidine 5 \200\22310mg by im or iv injection. Management of these symptoms s hould take place in hospital. CHAPTER 4 Formulary 336 Midazolam Description Sedative hypnotic benzodiazepine. Presentation - (Midazolam hydrochloride 1mg/ml, 50ml vial) - Midazolam hydrochloride 2mg/ml , 2ml and 5ml ampoules - Midazolam hydrochloride 5mg/ml, 2ml, 5ml, 10ml, and 18ml ampoules. Effects Acts through membrane GABA receptors to stabilize membranes, primarily in the CNS, and reduce depolarization. Indications - Sedation and amnesia for clinical procedures - Co-administration with ketamin e to reduce emergence phenomena (not required in children). Dose - 2 \200\2232.5mg (0.5 \200\2231mg in the elderly) by slow iv injection, increasing in increments of 1mg (0.5 \200\2231mg in elderly). Children: (by SLOW iv injection) 6 months \200\2235 yrs, initially 50 \200\223100ug/kg; 6 \200\22312 yrs, 25 \200\22350ug/kg. Further increments are given to effect. Contraindications Severe respiratory depression, acute pulmonary insufficiency, myasthenia gravis. Side-effects - Respiratory depression and arrest (overdosage or too rapid administration) Drowsiness, confusion, ataxia, amnesia, headache, vertigo. - Excitement and aggression (mor e common in children and the elderly). Notes Midazolam can also be given by im or rectal routes. DRUGS1 337 Morphine Description An opiate analgesic. Presentation - Morphine sulfate 10mg/ml, 15mg/ml, 20mg/ml, and 30mg/ml \200\2241 and 2ml ampoules Morphine sulfate 10mg/ml \200\2241ml pre-filled syringe - Morphine sulfate 1mg/ml \200\2241 0ml pre-filled syringe - Larger-volume vials are available but are intended for iv infusion preparation. Effects Binds to opiate receptors resulting in analgesia, euphoria, and respiratory depress ion. Indications Acute severe pain Dose - Morphine should be given by iv injection in small aliquots titrated to effect. An initial dose of 5mg is appropriate for an adult male, 2mg for smaller or older p atients. Doses of up to 30mg may be required in fit young men with severe pain. Children: up to 1 month, 37.5 \200\22375ug/kg; 1 \200\22312 months, 50 \200\223100ug/kg; 1 \200\2235 years, 1 \200\2232mg; 6 \200\22312 years, 2 \200\2235mg. All by iv injection. Contraindications Acute respiratory depression. Side-effects Nausea and vomiting, drowsiness, respiratory depression, hypotension, hallucin ations. Acute allergic reactions. Notes The labeling on ampoules of proprietary morphine is identical except for the concentr ation. It is imperative that this is carefully checked if dosing errors are to be avoided. Morphine should always be adminis- tered in a concentration of 1mg in 1ml (10mg in 10ml). An antiemetic should be administered with any iv opiate, however the use of Cyclimorph (morphine/cyclizine) is not recommended . Naloxone and equipment for mechanical ventilatory support MUST be available when morphine (or any other opiate) is administered. Morphine has a duration of action of about 2 hours. CHAPTER 4 Formulary 338 Naloxone Description A competitive opiate antagonist. Presentation - 400ug/ml, 1ml ampoule - 400ug/ml 1ml, 2ml, and 5ml pre-filled syringe - 1mg/ ml, 2ml pre-filled syringe. Effects Reversal of opioid effects. Indications - Reversal of therapeutic overdose of opiates - Treatment of opiate poisoning ( recreational overdose) - Treatment of unexplained loss/reduction of consciousness. Dose - 0.4mg(400ug) \200\2232mg repeated at intervals, as required, to a maximum of 10mg If naloxone is given to exclude opiates as a cause of loss of consciousness, a dose of 10mg should be given Children: intravenous 10ug/kg, subsequent dose of 100ug/kg if no response. Contraindications Caution in patients who are physically dependent on opiates; will precipi - tate pain in patients given opiate for analgesia. Side-effects Nausea and vomiting, tachycardia.