Current Anaesthesia & Critical Care (2002) 13, 70 ^75 2002 Published by Elsevier Science Ltd.cdoi:10.1054/cacc.2002.0385, available online at http://www.idealibrary.com onFOCUS ON: BURNS AND PLASTICSAnaesthesia for patients with burns injuriesK. Langley and K. SimMcIndoe Burns Centre, QueenVictoria Hospital NHS Trust, East Grinstead, West Sussex RH19 3DZ, UK KEYWORDS Summary The safe managementofcomplex burnsinjuriesrequires anunderstanding burns, general anaesthesia, of the obligatory pathophysiological changes and currenttreatment options.The anaes- regional anaesthesia, thetic team must have, collectively specialist skillsin resuscitation, airway management, , emergency treatment, critical care procedures and care of small children and access to expert advice in the transportation of patients management of non-burns co-morbidity The experience of treating relatively small . numbers of these patients for prolonged periods of time is unusual in anaesthetic prac- tice. Flexibility is required to tailor anaesthetic practices to ¢t with overall patient man- agement objectives. Communication skills are necessary for multidisciplinary team membership and in dealings with patients, relatives and managerial authorities. Regular commitment to burns anaesthesia is required to acquire and consolidate ex- pertise in this group of patients. Issues include altered drug e¡ects, monitoring, blood conservation techniques and choices in £uid therapy and environmental and metabolic control. The contribution of anaesthetic personnel to the management of burns patients con- tinues to evolve. T raditional roles in resuscitation and preparation for transfer, critical care, pain management, and anaesthesia for burns surgeryremainimportant but anaes- thetic inputisrequired to in£uence the future direction of acute burns care services, and to ensure that the training and development needs of current and future specialist per- sonnel are met. 2002 Published by Elsevier Science Ltd. cINTRODUCTION ASSESSMENTAlthough a specialist commitment to anaesthesia for The initial hospital assessment of a major burn should fol-burns patients is the province of a few, all anaesthetic low (advanced trauma life support) ATLS (advancedpersonnel should be competent to systematically assess trauma life support) guidelines with a primary surveyburns injuries and manage their transfer to specialist concentrating on the support of the airway, gas exchangeburns facilities. The causes and thus the presentation of and circulation.The secondary survey examines for asso-burns injuries are diverse, and include £ame burns, ciated trauma sustained during the accident or whilstscalds, electrical and chemical burns. Minor burns are trying to escape from the scene. Focusing on the burnscommonFin the UK 1% of the population sustains a injury requires:burn injury each year, 10% of whom require hospital ad- K An estimation of percentage surface areamission. Of these only around one in 10 have sustained a involvement.life-threatening injury, but the appropriate early man- K Assessment of depth of burned areas.agement of the burn wound and its systemic conse- K Determination of the evidence for inhalational injury.quences is a key factor in reducing morbidity. K Vascular or respiratory compromise secondary to The burns case mix is not representative of the gener- circumferential burns should be identi¢ed, andal population. Patients at the extremes of age are more escharotomy considered.vulnerable to injury, as are those with pre-existing mor- K The cornea should always be examined before facialbidities such as epilepsy and alcoholism.There is an asso- swelling makes assessment di⁄cult.ciation with psychiatric illness, and others, including K All patients with a history of exposure to smoke inchildren, su¡er non-accidental injuries. an enclosed space should be considered at risk of inhalation injury, even if the initial signs and sym-Correspondence to: KS. ptoms are unimpressive. Systemic toxicity secondary0953-7112/02/$-see front matter
ANAESTHESIA FOR PATIENTS WITH BURNS INJURIES 71 to the inhalation of toxic gases such as carbon halation causes progressive cough and dyspnoea and the monoxide must be recognized and treated. If the production of copious secretions. A low threshold for history is unclear, then blood should be retained for tracheal intubation and diagnostic ¢bre-optic broncho- toxicological analysis. scopy is recommended. The early institution of a regimeK The presence of associated injuries complicates of nebulized bicarbonate solution has proven to be bene- management, and in£uences priority setting and ¢cial in mobilizing secretions and reducing the incidence referral decisions. of mucous plugging. Other recommended regimes in- clude nebulized heparin and or N-acetyl cysteine.3 Major burns injuries (over 20% burn surface area in Patients with signi¢cant carboxyhaemoglobin levelsadults) require prompt resuscitation to treat the predict- (over 30%) require high inspired oxygen concentrationsable pathophysiological consequences.1 to reduce the half-life of COHb.The bene¢t of hyperbaricK Fluid shifts from the circulation are maximal in the oxygen treatment is questionable given the logistic ¢rst 8 h following injury but continue for 24 h. di⁄culties of managing major burns injuries in hyperbaricK There is generalized tissue oedema proportional to facilities. the extent of the burn surface area.K Cardiac output is initially depressedK Systemic vascular resistance is high. Venous access The goal of resuscitation is to restore ¢lling pressures Securing central venous access before generalized tissueand oxygen delivery as e¡ectively as possible. Resuscita- oedema obscures landmarks is preferable. ATLS teachingtion £uids are transfused to correct hypovolaemia, initi- has reduced the incidence of £uid under-resuscitation;ally directed by proscriptive formulae, most commonly over-enthusiastic volume loading should be avoided.the crystalloid-based Parkland regime. An accurate pa-tient weight is required. Calculating £uid prescriptionsin children needs adjustments from formulae to account Preparation for transferfor maintenance requirements. The adequacy of transfer equipment and drugs should be Traditionally, assessment of the adequacy of resuscita- checked. Guidelines for transfer management are widelytion has depended on simple parameters including heart available.4 All intravascular lines should be ¢rmly securedrate, blood pressure and urine output. It is increasingly prior to departure. Contingency plans for airway man-recognized that this approach fails to detect patients agement enroute should be agreed. Emergency intubationwith signi¢cant regional hypoperfusion, and emphasizes whilst in motion is hardly a preferred option, and inevita-the importance of expedite transfer from the casualty bly a number of patients will undergo tracheal intubationfacility to a specialist centre bed where appropriate and ventilation primarily for transfer. This can cause dif-haemodynamic monitoring can be arranged. Trend ¢culties in regions where burns intensive care resourcesmonitoring of £ow-based parameters is increasingly are scarce, but is preferable to a wait and hope policy.practiced. Tools such as oesophageal Doppler monitor- Prolonged transfers accentuate the requirement to accu-ing can be used to guide target-based resuscitation. rately measure and deliver resuscitation £uid volumes.Other less invasive measures of cardiac ¢lling and cardiac Monitoring appropriate to the patient condition shouldoutput including a transpulmonary double-indicator dilu- be available, with a facility to record and print data ontion technique that computes intrathoracic blood arrival.volume have been reported.2 Written information accompanying the patient should Anaesthetic involvement must be sought early for air- include a history of the burn and any associated injuries,way assessment, help in securing venous access and liai- initial examination details and treatment of the patientson in the arrangements for patient transfer. since the burn injury, including airway management, £uid volumes, urine output. If initial surgical escharotomies were performed these should be charted.Airway assessment It is widely acknowledged that patients with seriousInitially, thermal injury to the upper airway causes oede- burn injuries are best managed in specialist burn units.ma and potential respiratory obstruction. The combina- Early assessment and active intervention to manage thetion of facial burns, soot around the nose and mouth, and burn wounds can limit the systemic consequences of thea clear history of entrapment in a closed space dictates injury and speed functional recovery. High standardsactive airway management. Inspiratory noise, agitation of resuscitation, surgery and critical care are required,and tachypnoea combine to indicate impending respira- and early involvement of experienced sta¡ is necessary.tory obstruction. There are many aspects to be considered to achieve suc- Inhalation injury develops as a dynamic process; air- cessful outcome in burns injuries; the contribution ofway oedema generally increases over 12^24 h. Smoke in- anaesthetic members of the burns team remains of high
72 CURRENT ANAESTHESIA & CRITICAL CAREimportance for a substantial part of the patient’s hospital Surgery is indicated for full thickness injuries or whenexperience. the wound is unlikely to heal within a few weeks. SlowerAreas of in£uence include: healing wounds risk hypertrophic scar and contracture formation. Tangential excision is commonly practi-K Anaesthesia for burns surgery. cedFthis is the debridement of progressive amounts ofK Acute pain management. burns tissue until viable tissue is reached.6 This contrastsK Critical care. with the historical approach in which burns surgeons Airway, ventilation, haemodynamics waited for eschar to slough o¡, and then grafted skin TechnicalFline changes, onto granulating tissue. Advances in surgical, anaesthetic postpyloric feeding tubes. and critical care have made it possible to excise larger Nutrition and metabolic management areas of deep burns earlier, and close the wound with Infection controlFdiagnosis of ventilator-associated autologous or cadaveric skin, or a growing range of skin pneumonia. substitutes. The introduction of prompt burn excision with early grafting is believed to result in less scar forma-K Communication. tion and accelerates functional recovery. Hospital stay is Patient, surgeons, nurses, therapists, relatives decreased for small burns, but it is more di⁄cult toK Chronic pain, sleep issues. clearly demonstrate reduced length of in-patient stay for larger burns. The timing of surgery for burns wound can be classi-ANAESTHESIA FOR BURNS SURGERY ¢ed as:The burns theatre environment can be something of an K ImmediateFescharotomy, or injuries associated withacquired taste. The case mix, sta¡ and patient dynamics the accident.are complex and the technical aspects are demanding. K EarlyFtangential excision and grafting within 72 h.Repeated exposure to patients undergoing multiple sur- K IntermediateFtangential excision and graftinggical episodes demands patience and attention to detail beyond 72 h.to discern relevant changes in condition. K LateFpost-burn reconstruction. A dedicated burns theatre facility must be adequatelystocked and resourced. Theatre anaesthetic equipment In moderate size burns (less than 30%), wound closureand transport monitoring should be compatible with can be achieved in one procedure using partial thicknessthat used in the critical care rooms. Stock control in skin grafts from unburned donor sites. In larger burnstheatre will be in£uenced by infection control proce- partial thickness skin grafts are expanded by 3:1or more,dures, minimizing store of equipment in theatres. Single and cover is augmented by cadaver allograft which mayuse patient items are preferred and didactic cleaning remain adherent for more than 10 days before immuneschedules are needed between cases. Inevitably, the rejection ensues.turnover of patients is reduced.The temptation to share In very large burns where donor sites are limited, al-resource with general theatre facilities must also consid- ternative approaches include staged excision of the burnser infection control issues. The location and sta⁄ng of wound with reharvesting of autologous skin donor areaspost-anaesthetic recovery facilities may be problemati- or the use of arti¢cial skin substitutes to provide tem-cal, particularly for small children. porary cover. The practical conduct of burns anaesthesia requires Patients requiring later reconstructive burns surgery£exibility. Surgical episodes have to be seen in the con- need careful assessment. The extent of the surgery maytext of overall patient management. Momentum has not re£ect anaesthetic di⁄culties in venous access andto be maintained in the recovery process with targets airway management, so adequate time must be allo-set and progress judged. This philosophy will inform cated. Patients may travel large distances to maintainattitudes to fasting times, timing of surgery, sedation, continuity with a particular unit, making day-case ar-weaning and mobilization. rangements di⁄cult.Surgery Blood conservation techniquesModern surgical management strategies are directed at Debridement of major burns has the potential for signi¢-accurately assessing the depth of the burns wound, excis- cant blood loss, and it is prudent to con¢rm that ade-ing necrotic tissue to limit infection and the extent of the quate cross-matched blood and blood products ishypermetabolic response, and achieving wound closure, available before induction of anaesthesia. Surgical timingwith the ultimate goal of maximizing functional and cos- and technique in£uences bleeding, and vigilance is neces-metic recovery.5 sary to assess losses, especially when multiple surgical
ANAESTHESIA FOR PATIENTS WITH BURNS INJURIES 73teams work at di¡erent sites on the patient. Blood loss the distribution, transformation and excretion of drugs;has been estimated to range from 200 to 300 ml for each receptor populations are altered, and losses may occurpercent of the body surface area excised and grafted.7,8 through the burn wound. Polypharmacy is usual, and theMajor blood loss can be sudden and surgery may need potential for interactions high. Experienced pharmacyto be suspended while hypovolaemia is corrected. sta¡ have an important surveillance role. Naturally, prevention is better than cure, and strate- The acute phase response to severe burns injuries re-gies to keep blood loss to a minimum are an important sults in early changes in plasma protein levels. Albuminpart of surgical technique.Tourniquets should be used for levels fall and alpha-1 acid glycoprotein levels rise.all extremity burns. Subcutaneous in¢ltration of the Changes in the drug non-protein bound fraction can al-operative site using saline with adrenaline 1:1000 000 ter the pharmacological response.solution ‘to tumescence’ is highly e¡ective.9 A delay of In general, drug pharmacokinetics undergo a biphasic10 ^15 min before excision enhances the vasoconstrictive response in burns injury. The initial reduction in circulat-e¡ect. The technique appears to be safe with few and ing blood volume, cardiac output and tissue perfusion,only transient haemodynamic complications.10 There is a due to blood and £uid loss and increased vascular perme-surgical learning curve as there is a qualitative change in ability, reduces renal and hepatic blood £ow. This isthe tissue surface at excision, but graft take rates appear restored following the development of the hypermeta-not to be compromised. Other techniques shown to be bolic phase, usually after 48 h. There may be, however,useful are the use of temporary pressure dressings, impairment in renal tubular and hepatic function, so in-topical thrombin sprays, and topical adrenaline soaks. creased drug clearance may not necessarily result. Blood transfusion practices are in£uenced by risk^ The volume of distribution (Vd) of a drug may be al-bene¢t analyses of red cell transfusion and the availability tered by changes in protein binding and in extracellularof alternative plasma volume expanders. £uid volume, resulting from £uid loss, exogenous £uid Recent attention has concentrated on determining administration, and increased capillary permeability.objective indications for blood transfusion, with clinical Changes in loading dose may be required if the drug hasexperience suggesting that losses of up to 30% circulating a small volume of distribution or a narrow therapeuticvolume can be replaced with crystalloid or colloid solu- range. Total plasma clearance must be consideredtions alone.11 Haemoglobin concentrations above 8 g/l are when considering drug maintenance doses and dosageconsidered su⁄cient and there is no evidence that mod- intervals.erate anaemia impairs wound healing.12,13 A pharmacodynamic explanation has been proposed The trend away from the use of albumin, fuelled by for the e¡ects of burn injury on the e⁄cacy of musclecost issues and controversy around a published meta- relaxants. Burn injury causes proliferation of extrajunc-analysis of albumin in critical care patients has com- tional acetylcholine receptors (AchR) leading to resis-pounded the wide variation in £uid prescription tance to non-depolarizing muscle relaxants (NDMR),practices in the post acute phase burns patient.14 The and hypersensitivity to depolarizing muscle relaxants.17use of hydroxyethyl starches has spread, with prolonged This e¡ect may occur within a week of the injury, persistduration of e¡ect and e⁄cient volume expansion seen as for up to a year, and is proportional to the total burnsdesirable properties. However, a recent paper has raised surface area.the possibility that the use of hydroxyethyl starches may Dose requirements for all anaesthetic agents are gen-increase the risk of acute renal failure in patients with a erally increased in the burns population with their hyper-septic pro¢le.15 Reports of chronic itch are also of dynamic circulation and hypermetabolic state; MACconcern in a patient group already at high risk of this values are raised and the duration of action is decreased.complication. Tolerance to the e¡ects of sedative, analgesic and inotro- The persisting high-volume £uid exchanges required in pic medication is commonly seen but the range of re-severe burns injury patients emphasize the need for stu- sponse for individual patients is unpredictable.dies to better determine optimal £uid regimes in thepost acute phase. Manufacturers dosage recommenda-tions for new colloid solutions are derived from general Feeding and fastingcritical care population studiesFtheir relevance inburns patients is conjectural. Clinically, signi¢cant gastrointestinal dysmotility is com- mon in the burns population but repeated interruptions to the feeding regime for surgical procedures delays re- covery. Consideration should be given to the early insti-Pharmacology tution of postpyloric feeding, and intubated patients canAbnormal drug e¡ects are to be expected in burns pa- be fed throughout surgery. Anaesthetic techniques thattients.16 The host response to severe burns injuries re- permit early re-institution of feeding regimes postopera-sults in functional changes in organ systems controlling tively should be preferred, and the development of an-
74 CURRENT ANAESTHESIA & CRITICAL CAREtagonists to opioid-induced gastrointestinal status may theatre team. Body areas not being operated on shouldbe of advantage.18 be kept covered, and forced air warming devices used if The importance of tight glycaemic control in critical practicable. A radiant heater near the patient can be par-care patients has recently been promoted.19,20 Clear unit ticularly e¡ective at reducing heat loss. Intravenous £uidsfeeding protocols contribute to this by reducing the inci- should be warmed.dence of prolonged interruptions to enteral regimes. PAIN CONTROLMonitoring Burns pain is frequently poorly managed, with poorDuring anaesthesia there is a continual requirement to communication, drug side-e¡ects and anxiety and de-monitor the patient’s physiological state, to con¢rm cor- pression being contributory factors.22 Pain receptors inrect equipment function, and to avoid patient awareness. residual skin elements are stimulated, and the host re-Accepted recommendations state that the following sponse sensitizes receptors around the injury sites. Neu-monitoring devices are essential to the safe conduct of ropathic pain develops secondary to nerve damage,anaesthesia: pulse oximetry, non-invasive blood pressure abnormalities in nerve regeneration and central nervousmonitor, ECG and capnography.21 The extent to which system reprogramming.the patient is assessed beyond the minimal standards of In the acute stage, the assessment of pain in the criticalmonitoring should be determined by the patient’s medi- care burns patient is di⁄cult as the usual signs includingcal condition and the proposed extent of surgery. hypertension, tachycardia, sweating and agitation areSpeci¢c issues in the burns patient include obscured. The pattern of burns depth or area providesK Di⁄culties in placement of monitoring equipment. few clues as to pain severity but e¡ective analgesia is im- portant to prevent the physiological, functional and psy- The standard sites for placement of ECG electrodes chological consequences of severe or protracted pain.are often unavailable, and it may be di⁄cult to make the Opioid doses titrated to response remains the main-gel electrodes adhere to damaged skin. Options to over- stay of therapy, and side-e¡ects must be accepted andcome these di⁄culties include attaching the ECG leads managed. Combination therapy with low-dose ketamineto surgical staples or steel sutures placed in burned infusions, regular paracetamol and judicious use of non-areas, or accepting the trace obtained by electrode pla- steroidal in£ammatory agents can be opioid sparing,cement at distant sites. though NSAID side-e¡ects limit their use. Even with all limbs burned it can be possible to place ablood pressure cu¡ and obtain a reliable reading. How- K Sodium and water retention.ever, for all extensive procedures invasive measurement K Inhibition of renal prostaglandin production.is indicated, with the bene¢ts of pulse-contour analysis, K Inhibition of platelet aggregation.and ease of blood sampling. K Small bowel villous atrophy. K Extensively protein bound, so e¡ects potentiated byK Access to usual sites hypoproteinaemia. Pulse oximetry may be unreliable in the presence of Antidepressant therapy should be started early andcarboxyhaemoglobin or in shocked, vasoconstricted pa- may be bene¢cial in improving sleep patterns.tients or those with peripheral burns. Attachment of Following discharge from critical care regular assess-probes to central sites, such as ear, nose, lip, or tongue ments of severity (those recorded by the professionalsmay be helpful. Access to neck veins for central venous generally correlate poorly with the patient’s own assess-pressure monitoring may be precluded by burns wounds. ment) are needed, and distinction between backgroundK Temperature monitoring and procedural pain is important, as di¡erent strategies are needed for each. This is manadatory in all but the shortest procedures. Background pain may be present continually. At ¢rst,The combination of lengthy procedures in cold operating intravenous opioids by infusion or patient-controlled an-theatres, large exposed areas of body surface, and ad- algesia (PCA), will be needed to control pain. Once feed-ministration of large volumes of £uids, can lead to ing has been established the enteral route can be used,marked intraoperative hypothermia. with long acting oral opioids supplemented, as necessary, Infants below 6 months are unable to shiver and pro- with shorter acting preparations for breakthrough pain.longed hypothermia risks hypoxia and acidosis through Procedures, including surgery, dressing changes, andadaptive brown fat metabolism. Infants and children have physiotherapy, may require more intense analgesia. Poorhigher relative evaporative heat loss than adults. management can lead to a high degree of anticipatory an- The ambient theatre temperature should be warm, xiety for future procedures, lowering pain tolerance, soabove 271C, despite the discomfort this causes to the early failure is poorly tolerated. Bolus alfentanil doses
ANAESTHESIA FOR PATIENTS WITH BURNS INJURIES 75and patient-controlled propofol techniques have been 9. Robertson R D, Bond P, Wallace B, Shewmake K, Cone J. The tu-used successfully and recovery times are markedly short- mescent technique to signi¢cantly reduce blood loss during burner than conventional practice with oral opioid and surgery. Burns 2001; 27: 835^ 838. 10. Cartotto R, Musgrave M A, Beveridge M, Fish J,Gomez M. Minimiz-benzodiazepine combinations. Regional anaesthetic ing blood loss in burn surgery. J Trauma 2000; 49:1034 ^1039.techniques may be available, depending on the burns dis- 11. Carson J L, Du¡ A, Berlin J A et al. Perioperative blood transfusiontribution but topical local anaesthetic application has and postoperative mortality. JAMA1998; 279: 199^205.proven disappointing in our hands, with variable e¡ect. 12. Wahr J A. Myocardial ischaemia in anaemic patients. Br J Anaesth Prolonged pain can develop co-incident to the healing 1998; 81 (Suppl 1): 10 ^15. 13. Hopf H W, Viele M, Watson J J et al. Subcutaneous perfusion andprocess and tissue regeneration, associated with itching oxygen during acute severe isovolemic hemodilution in healthyand tingling. The chronic pain state that emerges often volunteers. Arch Surg 2000; 135: 1443^1449.has multiple, often unclear origins of pain, and can be 14. Cochrane Injuries Group Albumin Reviewers. Human albuminfrustratingly unresponsive to conventional regimes. Ad- administration in critically ill patients: systematic review of randomised controlled trials. BMJ1998; 317: 235^240.juvant therapies include clonidine, and anticonvulsants 15. Schortgen F, Lacherade J C, Bruneel F et al. E¡ects of hydro-which are e¡ective in the treatment of sympathetically xyethylstarch and gelatin on renal function in severe sepsis: a multi-maintained pain.23 Psychological therapies to boost centre randomised study. Lancet 2001; 357: 91 1^916.coping strategies and aid relaxation bene¢t many 16. Weinbren M J. Pharmacokinetics of antibiotics in burn patients. Jpatients. Antimicrob Chemother 1999; 44: 319^327 . 17 Marathe P H, Dwersteg J F, Pavlin E G, Haschke R H, Heimbach D . M, Slattery J T E¡ect of thermal injury on the pharmacokinetics . and pharmacodynamics of atracurium in humans. Anesthesiology 1989; 70: 752^755.REFERENCES 18. Taguchi A, Sharma N, Saleem R M et al. Selective postoperative inhibition of gastrointestinal opioid receptors. N Engl J Med 2001;1. Monafo W W. Initial management of burns. N Engl J Med1996; 335: 345: 935^940. 1581^1586. 19. van den Berghe G, Wouters P, Weekers F et al. Intensive insulin2. Holm C, Melcer B, Horbrand F, Worl H, von Donnersmarck G H, therapy in the surgical intensive care unit. N Engl J Med 2001; 345: Muhlbauer W. Intrathoracic blood volume as an end point in resus- 1359^1367 . citation of the severely burned: an observational study of 24 pa- 20. Gore D C, Chinkes D, Heggers J, Herndon D N, Wolf S E, Desai M. tients. J Trauma 2000; 48: 728 ^734. Association of hyperglycemia with increased mortality after severe3. Akinniranye O A, Pal S K. Inhalation injuryFcurrent concepts and burn injury. J Trauma 2001; 51: 540 ^544. management. In: Kaufman L,Ginsberg R (eds). Anaesthesia Review, 21. Recommendations for Standards of Monitoring during Anaesthesia Vol.15,1999; 81^102. Churchill Livingstone. London. and Recovery. The Association of Anaesthetists of Great Britain4. Wallace P G, Ridley S A. ABC of intensive care. Transport of criti- and Ireland, London, 2000 www.aagbi.org. cally ill patients. BMJ1999; 319: 368 ^371. 22. Gallagher G, Rae C P, Kinsella J. Treatment of pain in severe burns.5. Kao C C,Garner W L. Acute Burns. Plast Reconstr Surg 2000; 101: Am J Clin Dermatol 2000; 1: 329^335. 2482^2493. 23. Pal S K,Cortiella J, Herndon D. Adjunctive methods of pain control6. Janzekovic Z. A new concept in the early excision and immediate in burns. Burns 1997; 23: 404 ^ 412. grafting of burns. J Trauma 1970; 10: 1103^1108.7 Budny P G, Regan P J, Roberts A H. The estimation of blood loss . during burns surgery. Burns 1993; 19:134 ^137 . FURTHER READING8. Moran K T, O’ReillyT J, Furman W, Munster A M. A new algorithm for calculation of blood loss in excisional burn surgery. Am Surg MacLennan N, Heimbach D M,Cullen B F. Anesthesia for major thermal 1988; 54(4): 207^208. injury. Anesthesiology 1998; 89: 749^770.