Blood conservation in elective surgery

Blood conservation for elective surgery involves both the reduction of blood loss and the reduction of homologous blood transfusion. Methods of reducing blood loss such as the use of tourniquets, vasoconstrictor drugs, regional anaesthetic supplements and hypotensive anaesthesia are considered briefly. Preoperative and intraoperative techniques of autotransfusion and haemodilution are considered in detail, including a technique of scavenging and reinfusing blood aspirated from the surgical site.     

Blood transfusion requirements in elective breast reconstruction surgery

IntroductionExcess-ordering of cross-matched blood in preparation for elective surgery is expensive with associated blood shortages and time-expired wastage. Although, the maximum surgical blood order schedule (MSBOS) for breast reconstruction recommends pre-operative cross-match of 2–6 units of red cell concentrate, there is no data confirming whether this guideline is observed in practice or whether compliance results in improved outcome. The aim of this study was to examine the utility of this MSBOS in clinical practice by assessing its performance in a validation set of patients.Materials and MethodsOver a three year period, 49 patients undergoing 50 consecutive elective breast reconstruction surgery were assessed for demographic data, surgical information and hematological/transfusion data to compare the number of units of blood cross-matched with those subsequently transfused for elective breast reconstruction surgery. This was in lieu of updating the current maximal surgical blood order schedule of cross-matching 2–6 units pre-operatively.ResultsFifty elective operations were undertaken during the study period with a zero peri-operative blood transfusion requirement and a 8% post-operative blood transfusion requirement. Pre-operative cross-match to transfusion ratio was unacceptably high with a time-expired blood wastage of 8.7%.DiscussionThese data thus indicate that adoption of a type and screen policy is satisfactory for haemorrhage risk management of elective breast reconstruction. The MSBOS is not designed to predict post-surgery blood needs and a requirement based blood ordering protocol will optimise blood utilisation efficiency.     

Selective decontamination of the colon before elective colorectal surgery

The controversy over the route of administration of antibiotic prophylaxis in patients undergoing elective colorectal operations persists for oral, parenteral, and a combination of the two routes. The oral antibiotics commonly administered for colorectal prophylaxis, neomycin and eythromycin base, are not absorbed in the gastrointestinal tract (GIT). However, the 4-fluoroquinolones are absorbed in the upper GIT and are excreted in part by the colonic mucosa. Their action is then to remove, or severely depress, the gram-negative aerobic bacilli leaving the anaerobic flora unaffected. This action is the principle of selective decontamination. We have assessed the efficacy of oral ciprofloxacin in a prospective randomized clinical trial in which all patients received piperacillin 4 g IV as single-dose parenteral prophylaxis. A group of 327 evaluable patients were randomized to receive ciprofloxacin 500 mg b.i.d. with the preoperative cathartic (group OA, n=159) or no oral antibiotic (11.3%) patients in group OA and 39 (23.2%) patients in group NOA (² = 7.2, p=0.007). Operation-related infection of any type occurred in 23 (14.5%) patients in group OA compared with 55 (32.7%) in group NOA (² = 14.0, p=0.0002). The median postoperative hospital stay was 11 days (interquartile range 4.5 days) for group OA and 12 days (interquartile range 8 days) for group NOA (Mann Whitney U test, p=0.005). Ignoring the treatment group, the median postoperative hospital stay was 17 days (interquartile range 10 days) for infected patients and 11 days (interquartile range 4 days) for those not infected. We conclude that the administration of ciprofloxacin 500 mg b.i.d. with the preoperative cathartic significantly reduces the incidence of infection after elective colorectal operations and should form part of the preoperative preparation for such operations.

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Resumen Persiste la controversia sobre la ruta oral, parenteral o su combinación de administración de los antibióticos profilácticos en pacientes que van a ser sometidos a cirugía colorrectal. Los antibióticos orales más comunmente administrados para profilaxis colorrectal, la neomicina y la eritromicina base, no son absorbidos en el tracto gastrointestinal. Sin embargo, las fluroquinolonas si son absorbidas en el tracto GI superior y son excretadas en parte por la mucosa colónica. Su acción es, por tanto, la de eliminar o reducir los bacilos aeróbicos Gram-negativos, sin afectar la flora anaeróbica. Tal es el principio de la descontaminación selectiva. Hemos evaluado la eficacia de la ciprofloxacina oral en un ensayo prospectivo y randomizado, en el cual la totalidad de los pacientes recibió piperacilina 4 g IV en dosis única como forma de profilaxis parenteral. Se escogieron al azar 327 pacientes valorables para recibir ciprofloxacina 500 mg BD con el agente preoperatorio de catarsis (Grupo OA, n=159) o ningún antibiótico oral (Grupo NOA, n=168). Se registró infección de la herida en 18 (11%) de los pacientes en el Grupo OA y en 39 (25%) de los del Grupo NOA (Chi²=7.2, p=0.007). Se presentó infección, de cualquier tipo relacionada con la operación, en 23 (14.5%) de los pacientes en el Grupo OA y en 55 (32.7%) de los del Grupo NOA (Chi²=14.0, p=0.0002). La estancia hospitalaria postoperatoria media fue de 11 días (rango interquartil 4.5 days) en el Grupo OA y de 12 días (rango i. 8 días) en el Grupo NOA (prueba U de Mann Whitney p=0.005). Al no tener en cuenta el Grupo de tratamiento, la estancia postoperatoria media fue de 17 días (rango i. 10 días) para los pacientes infectados, y de 11 días (rango i. 4 días) para los no infectados. Nuestra conclusión es que la administración profiláctica de ciprofloxacina en dosis preoperatoria de 500 mg BD concomitante con el agente catártico reduce en forma significativa la incidencia de infección luego de operaciones colorrectales y que debe ser parte de la preparación preoperatoria para tal tipo de cirugía.

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Résumé La controverse concernant la meilleure voie d'administration d'antibiotiques prophylactiques chez le patient opéré du côlon à froid persiste toujours: voie orale, voie parentérale ou les deux combinées. Les antibiotiques du type néomycine et érythromycine ne sont pas absorbés par le tube digestif. Les 4-fluoro-quinolones, cependant, sont absorbés dans le tube digestif supérieur et sont ensuite excrétés en partie par la muqueuse colique. Leur action consiste donc à éliminer ou du moins déprimer fortement les bactéries aérobies Gram négatif sans pour autant affecter les bactéries anaérobies. Ceci est la base de la décontamination dite sélective. Nous avons testé l'efficacité de la ciprofloxacine par voie orale dans un essai prospectif randomisé chez des patients ayant de toutes manières de la piperacilline par voie intraveineuse (4 gr) en dose unique. Trois cent vingt-sept patients ont été randomisés pour recevoir en même temps que leur préparation colique mécanique de la ciprofloxacine (500 mg x 2) (group OA, n=159) ou non (groupe NOA, n=168). On a constaté une infection pariétale chez 18 (11%) des patients du groupe OA et chez 39 (25%) des patients du groupe NOA (Chi²=7.2, p=0.007). Une complication infectieuse a été notée chez 23 (14.5%) des patients du groupe OA et chez 55 (32.7%) des patients du groupe NOA (Chi²=14.0, p=0.0002). La durée médiane du séjour hospitalier a été de 11 jours (valeur interquartile = 4.5 jours) dans le groupe OA et de 12 (valeur interquartile = 8 jours) dans le groupe NOA (p=0.005) par le U-test de Mann-Whitney. Sans tenir compte du groupe de tirage au sort, la durée médiane de séjour hospitalier pour les patients infectés a été de 17 (valeur interquartile = 10 jours) comparés à 11 (valeur interquartile = 44) jours pour les patients non-infectés. Nous concluons que l'administration de ciprofloxacine 500 mg en deux fois en même temps que la préparation mécanique, réduit de façon significative l'incidence d'infection après une intervention colique à froid et devrait être systématique pour ce type de chirurgie.

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The following surgeons and microbiologists participated in this study: D. Bremner, J. Gollock, and M. Browne at Borders General Hospital, Melrose; C. Morran, B. Sugden, and R. Hardie, at Crosshouse Hospital, Kilmarnock; A. Walls, M. Henderson, J. McCormick, C. Auld, and F. Bone at Dumfries & Galloway Royal Infirmary; J. MacDonald and J. McGavigan at Falkirk District Royal Infirmary; J. Goldring at Hairmyres Hospital, East Kilbride; J.J. Morrice, G. Bell, and V. Biggs at Inverclyde Royal Hospital; M.K. Browne, J. McKenzie, R. Brooks, and J. Thomson at Monklands District General Hospital, Airdrie; K. Mitchell and F. Russell at Royal Alexandra Hospital, Paisley; J. Ferguson, G. McBain, A. Litton, and G. Lindsay at Southern General Hospital, Glasgow; R. Dalling, J. Smith, and A. Girdwood at Stobhill General Hospital; E.W. Taylor, J.R. Maccallum, P.J. Shouler, and A. Eastaway at Vale of Leven District General Hospital; J. Drury, I. Smith, and P. Redding at Victoria Infirmary, Glasgow.     

Anergic patients before elective surgery have enhanced nonspecific host-defense capacity

Albeit anergy in patients before surgery is associated with an increase in septic-related complications and mortality, it is not clear whether this is due to a downregulated nonspecific host defense or a specific cellular immune defect. We studied polymorphonuclear leukocyte neutrophil (PMN) function in 14 patients who were admitted for elective surgery and compared them with 5 healthy controls. At admission, patients were classified according to their delayed-type hypersensitivity skin test response into reactive or anergic groups. In vivo PMN delivery to skin windows, the plasma lactoferrin level, serum and skin window fluid chemoattractant activity, and in vitro superoxide production were measured. Compared with reactive patients, anergic patients showed an increased cell delivery (8.7 x 10(6) PMNs per well vs 1.6 x 10(6) PMNs per well), an increased plasma lactoferrin level (4.4 +/- 1.5 mg/L vs 3.1 +/- 0.8 mg/L), an increased chemoattractant capacity of serum and skin window fluid (38 +/- 21 cells per high-power field vs 16.8 +/- 7.2 cells per high-power field), and an increased superoxide production. We concluded that nonspecific host defense, as reflected by PMNs, is enhanced in anergic patients before surgery and may not explain the increased susceptibility to infection.     

Parental anxiety before elective surgery in children A British perspective

This study measures the anxiety levels in 100 parents of children scheduled for elective surgery at the Royal Aberdeen Children's Hospital. Anxiety levels were quantified using the Leeds scale for self-assessment of anxiety. Forty-two per cent of parents were significantly anxious. Mothers were identified as being more pathologically anxious than fathers. The 'anxious' parents were specifically more anxious about the surgery, anaesthesia, postoperative pain and treatment, and hospitalisation in general. All parents, whether identified as anxious or not, agreed on factors likely to reduce anxiety: pre-operative information from staff, being able to accompany their child to the operating theatre and being present at induction of anaesthesia.     

Critical appraisal of cardiac risk stratification before elective vascular surgery

This study was undertaken to evaluate the efficacy of the cardiac risk stratification protocol proposed by the American College of Cardiology/American Heart Association (ACC/AHA) in predicting cardiac morbidity and mortality associated with elective, major arterial surgery. Cardiac risk stratification using ACC/AHA guidelines was done on 425 consecutive patients before 481 elective cerebrovascular (n = 146), aortic/inflow (n = 166), or infrainguinal (n = 169) procedures at an academic Veterans Affairs Medical Center. Cardiac risk was stratified as low, intermediate, or high based on clinical risk factors, such as, Eagle criteria, history of cardiac intervention, patient functional status, results of noninvasive cardiac stress testing, and coronary angiography with coronary revascularization performed when appropriate. Outcomes (myocardial infarction, unstable angina, congestive heart failure, ventricular arrhythmia, cardiac death, and mortality) within 30 days of surgery were compared between the various risk stratification groups. Univariate and multivariate analyses were used to identify clinically useful prognostic variables from the preoperative cardiac evaluation algorithm. Overall mortality (1.7%), cardiac death (0.4%), and adverse cardiac event (4.8%) rates were low, but cardiac death and morbidity were increased (p < 0.05) in high-risk stratified patients (3.4%, 11.9%) compared to intermediate (0%, 2.8%) and low (0%, 4.0%) cardiac risk groups. The presence of 3-vessel angiographic coronary artery occlusive disease was an independent predictor of cardiac morbidity, while inducible ischemia by cardiac stress imaging was not. Previous coronary revascularization was associated with increased mortality as was the development of a non-cardiac complication. Cardiac risk assessment identified 78 (18%) patients with indications for coronary angiography. Angiographic findings resulted in coronary artery intervention (9-angioplasty; 4-bypass grafting) in 13 (3%) patients who experienced no adverse cardiac events after the planned vascular surgery (15 procedures). Cardiac risk stratification using ACC/AHA guidelines can predict adverse cardiac events associated with elective vascular surgery; however, protocol modification by increased reliance on Eagle criteria and less use of cardiac stress testing can improve identification of the "highest risk" patients who may benefit from prophylactic coronary intervention.     

Blood loss and transfusion in elective abdominal aortic aneurysm surgery

BACKGROUND: Intraoperative blood loss and transfusion are known determinants of mortality and morbidity of elective abdominal aortic aneurysm (AAA) repair. The present study analysed the pattern of blood loss and transfusion and evaluated the risk factors of blood loss during open repair of infrarenal AAA. METHODS: Blood loss, transfusion and fluid replacement during elective open repair operation for patients with infrarenal AAA were correlated to demographic data, operative findings and procedural information. RESULTS: A total of 129 patients with a mean age of 71 years was analysed. The mean blood loss was 1000 +/- 887 mL (200-6000 mL). Blood transfusion, with a mean transfusion volume of 400 +/- 591 mL (0-3000 mL), was required in 46% of patients. Univariate analysis showed that bodyweight, renal impairment, low haemoglobin and platelet counts, iliac artery involvement, large aneurysm, bifurcated graft, large graft diameter, prolonged aortic clamp time and long operation time were associated with a higher blood loss. A haemoglobin level of <10.5 g/dL (relative risk (RR): 4.6), platelet count <130 x 10(9)/L (RR: 3.9), aortic clamp time >50 min (RR: 15), total operation time >200 min (RR: 11) and type of graft (RR: 3.5) were identified as independent determinants of blood loss on multivariate analysis. CONCLUSION: Intraoperative blood loss in elective infrarenal aneurysm surgery is influenced by patients' haematological parameters, distal involvement of aneurysm and degree of difficulty of operation.     

Blood transfusions and postoperative infections in patients undergoing elective surgery

BACKGROUND: Postoperative infections result from the interactions of bacteria, the surgical technique, and host defense mechanisms. Thus, identifying single determinant factors has proved difficult. MAGNITUDE OF THE RISK: In a recent survey of 2,809 colorectal resections, transfusion was the single most powerful risk factor for postoperative infection. In patients undergoing primary hip or knee prosthesis insertion, the transfusion of allogeneic blood increased the risk of a deep-seated infection by a factor of 12. MECHANISMS: Several host defense mechanisms are impaired by blood products. The initial hypothesis incriminated the transfused white blood cells, but this paradigm has since been challenged. The effects of free serum iron, the blood storage time, and the presence in stored blood of bioactive substances such as inhibitors of metalloproteinase-1 may also be important. CONCLUSION: It is worth pursuing efforts to emphasize autologous blood transfusion and the reinfusion of shed blood as blood conservation strategies, as these practices reduce the risk of infectious complications.     

Premedication before elective breast surgery, a comparison between ketobemidone and midazolam

One hundred female patients scheduled for elective breast surgery (mean age 60 +/- 11 years were randomly assigned to receive one of two premedications: ketobemidone (Ketogan) 1-1.5 ml or midazolam 4-5 mg, intramuscularly. The effects on preoperative anxiety and postoperative emetic sequelae were studied. All patients were anaesthetised with thiopentone, fentanyl and atracurium, and ventilated with a mixture of nitrous oxide in oxygen with supplementary isoflurane. Sixty-nine percent of the midazolam- and 50% of the ketobemidone-premedicated patients experienced a reduction in anxiety. Midazolam was found to be more effective than ketobemidone in reducing anxiety among more tense patients--those with a VAS grading before premedication of 2 or more (P less than 0.05). Midazolam-premedicated patients were also assessed by observers as being more relaxed (P less than 0.05). No difference was seen in the frequency of emetic sequelae: 20 patients in the midazolam group and 14 patients in the ketobemidone group vomited once or more during the 24-h observation period. There was no difference between the two groups in time until an analgetic was required. In conclusion, midazolam seemed more effective in reducing preoperative anxiety than ketobemidone without any negative effects on postoperative emesis or time until an analgetic was required.     

The measurement of adult blood pressure and management of hypertension before elective surgery

This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to fulfil this criterion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hypertensive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in primary care. Patients who present to pre‐operative assessment clinics without documented primary care blood pressures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic.