The relationship between pre‐operative hypertension and intra‐operative haemodynamic changes known to be associated with postoperative morbidity

Hypertension is not consistently associated with postoperative cardiovascular morbidity and is therefore not considered a major peri‐operative risk factor. However, hypertension may predispose to peri‐operative haemodynamic changes known to be associated with peri‐operative morbidity and mortality, such as intra‐operative hypotension and tachycardia. The objective of this study was to determine whether pre‐operative hypertension was independently associated with haemodynamic changes known to be associated with adverse peri‐operative outcomes. We performed a five‐day multicentre, prospective, observational cohort study which included all adult inpatients undergoing elective, non‐cardiac, non‐obstetric surgery. We recruited 343 patients of whom 164 (47.8%) were hypertensive. An intra‐operative mean arterial pressure of < 55 mmHg occurred in 59 (18.2%) patients, of which 25 (42.4%) were hypertensive. Intra‐operative tachycardia (heart rate> 100 beats.min^?1) occurred in 126 (38.9%) patients, of whom 61 (48.4%) were hypertensive. Multivariable logistic regression did not show an independent association between the stage of hypertension and either clinically significant hypotension or tachycardia, when controlled for ASA physical status, functional status, major surgery, duration of surgery or blood transfusion. There was no association between pre‐operative hypertension and peri‐operative haemodynamic changes known to be associated with major morbidity and mortality. These data, therefore, support the recommendation of the Joint Guidelines of the Association of Anaesthetists of Great Britain and Ireland (AAGBI) and the British Hypertension Society to proceed with elective surgery if a patient's blood pressure is < 180/110 mmHg.     

Pre‐operative variables including fitness associated with complications after oesophagectomy

Oesophagectomy is a technically‐demanding operation associated with a high level of morbidity. We analysed the association of pre‐operative variables, including those from cardiopulmonary exercise testing, with complications (logistic regression) and survival and length of stay (Cox regression) after scheduled transthoracic oesophagectomy in 273 adults, in isolation and on multivariate testing (maximum Akaike information criterion). On multivariate analysis, any postoperative complication was associated with ventilatory equivalents for carbon dioxide, odds ratio (95%CI) 1.088 (1.02–1.17), p = 0.018. Cardiorespiratory complications were associated with FEV₁ and pre‐operative background survival (in an analogous group without cancer), odds ratios (95%CI) 0.55 (0.37–0.80), p = 0.002 and 0.89 (0.82–0.96), p = 0.004, respectively. Survival was associated with the ratio of expected‐to‐observed ventilatory equivalents for carbon dioxide and predicted postoperative survival, hazard ratios (95%CI) 0.17 (0.03–0.91), p = 0.039 and 0.96 (0.90–1.01), p = 0.076. Length of hospital stay was associated with FVC, hazard ratio (95%CI) 1.38 (1.17–1.63), p < 0.0001.     

The association of pre‐operative home accelerometry with cardiopulmonary exercise variables

We investigated the association of pre‐operative activity, reported by the Duke Activity Score Index, Short Form‐12 and measured by an accelerometer worn at home, with five cardiopulmonary exercise variables: peak power; peak oxygen consumption; anaerobic threshold; and ventilatory equivalents for oxygen and carbon dioxide. Fifty patients scheduled for major surgery underwent a standard pre‐operative cardiopulmonary exercise test and wore a chest‐mounted triaxial accelerometer for a mean (SD) duration of 3.2 (0.4) days. The Duke Activity Score Index and six accelerometer variables were significantly correlated with all five cardiopulmonary exercise variables, Pearson correlation coefficients 0.5–0.7, p = 0.02 to p < 0.001. Our results can guide future studies that measure physical activity for pre‐operative assessment and interventions.     

International consensus statement on the peri‐operative management of anaemia and iron deficiency

Despite current recommendations on the management of pre‐operative anaemia, there is no pragmatic guidance for the diagnosis and management of anaemia and iron deficiency in surgical patients. A number of experienced researchers and clinicians took part in an expert workshop and developed the following consensus statement. After presentation of our own research data and local policies and procedures, appropriate relevant literature was reviewed and discussed. We developed a series of best‐practice and evidence‐based statements to advise on patient care with respect to anaemia and iron deficiency in the peri‐operative period. These statements include: a diagnostic approach for anaemia and iron deficiency in surgical patients; identification of patients appropriate for treatment; and advice on practical management and follow‐up. We urge anaesthetists and peri‐operative physicians to embrace these recommendations, and hospital administrators to enable implementation of these concepts by allocating adequate resources.     

Pre‐operative anaemia,intra‐operative hepcidin concentration and acute kidney injury after cardiac surgery: a retrospective observational study

Acute kidney after cardiac surgery is more common in anaemic patients, whereas haemolysis during cardiopulmonary bypass may lead to iron‐induced renal injury. Hepcidin promotes iron sequestration by macrophages: hepcidin concentration is reduced by anaemia and increased by inflammation. We analysed the associations in 525 patients between pre‐operative anaemia (haemoglobin < 130 g.l^?1 in men and < 120 g.l^?1 in women), intra‐operative hepcidin concentration and acute kidney injury (dialysis or > 26.4 μmol.l^?1 or > 50% creatinine increase during the first two days after cardiac surgery. Rates of pre‐operative anaemia and postoperative kidney injury were 109/525 (21%) and 36/525 (7%), respectively. The median (IQR [range]) intra‐operative hepcidin concentration was 20 (10–33 [0–125]) μg.l^?1 and was lower in anaemic patients than those who were not: 15 (4–28 [0–125]) μg.l^?1 vs. 21 (12–33 [0–125]) μg.l^?1, respectively, p = 0.002. Four variables were independently associated with postoperative kidney injury, for which the beta‐coefficients (SE) were: minutes on cardiopulmonary bypass, 0.016 (0.004), p < 0.001; intra‐operative hepcidin concentration, 0.032 (0.008), p < 0.001; pre‐operative anaemia, 1.97 (0.56), p < 0.001; and Cleveland clinic risk score, 0.88 (0.35), p = 0.005. Contrary to generally increased rates of kidney injury in patients with higher hepcidin concentrations, rates of kidney injury in anaemic patients were lower in patients with higher hepcidin concentrations, beta‐coefficient (SE) ?0.037 (0.01), p = 0.007. In cardiac surgical patients the rate of postoperative acute kidney injury predicted by the Cleveland risk score might be adjusted for pre‐operative anaemia and intra‐operative cardiopulmonary bypass time and hepcidin concentration. Pre‐operative correction of anaemia, reduction in intra‐operative bypass time and modification of iron homeostasis and hepcidin concentration might reduce acute kidney injury.     

Association of Anaesthetists guidelines: cell salvage for peri‐operative blood conservation 2018

The use of cell salvage is recommended when it can be expected to reduce the likelihood of allogeneic (donor) red cell transfusion and/or severe postoperative anaemia. We support and encourage a continued increase in the appropriate use of peri‐operative cell salvage and we recommend that it should be available for immediate use 24 h a day in any hospital undertaking surgery where blood loss is a recognised potential complication (other than minor/day case procedures).     

A systematic review of information format and timing before scheduled adult surgery for peri‐operative anxiety

We included 34 trials with 3742 participants, identified through 6 database and supplementary searches (to May 2017): 29 were randomised; 4 were quasi‐randomised and 1 was cluster‐randomised. Disparate measurements and outcomes precluded meta‐analyses. Blinding was attempted in only 6 out of 34 (18%) trials. A multimedia format, alone or in combination with text or verbal formats, was studied in 20/34 (59%) trials: pre‐operative anxiety was unaffected in 10 out of 14 trials and reduced by the multimedia format in three; postoperative anxiety was unaffected in four out of five trials in which formats were compared. Multimedia formats increased knowledge more than text, which in turn increased knowledge more than verbal formats. Other outcomes were unaffected by information format. The timing of information did not affect pre‐operative anxiety, postoperative pain or length of stay. In conclusion, the effects of pre‐operative information on peri‐operative anxiety and other outcomes were affected little by format or timing.     

The association between pre‐operative variables,including blood pressure,and postoperative kidney function

We used multivariate analyses to assess the association of pre‐operative variables with kidney function in 41,523 adults after scheduled surgery in a single large academic hospital. Eight variables were independently associated with a reduction in postoperative estimated glomerular filtration rate: pre‐operative renal function; age; ASA physical status; cardiac failure; anaemia; cancer; type of surgery; and the lowest quartile of pre‐operative mean arterial blood pressure (< 71 mmHg). The estimated glomerular filtration rate fell by a mean (95% CI) of 2.7 (0.04–5.40) ml.min^?1.1.73 m^?2 for patients with a pre‐operative mean arterial pressure < 71 mmHg, p = 0.047. The same variables and male sex were associated with postoperative acute kidney injury. The odds ratio (95% CI) for acute postoperative kidney injury was 1.9 (1.2–2.9) for patients with a pre‐operative mean arterial blood pressure < 71 mmHg, p = 0.005.     

Impact of a peri‐operative quality improvement programme on postoperative pulmonary complications

Postoperative pulmonary complications are common, with a reported incidence of 2–40%, and are associated with adverse outcomes that include death, longer hospital stay and reduced long‐term survival. Enhanced recovery is now a standard of care for patients undergoing elective major surgery. Despite the high prevalence of pulmonary complications in this population, few elements of enhanced recovery specifically address reducing these complications. In 2013, a prevalence audit confirmed a postoperative pulmonary complication rate of 16/83 (19.3%) in patients undergoing elective major surgery who were admitted to critical care postoperatively. A quality improvement team developed and implemented ERAS+, an innovative model of peri‐operative care combining elements of enhanced recovery with specific measures aimed at reducing pulmonary complications. ERAS+ was introduced in June 2014, with full implementation in September 2014. Patients were screened during full ERAS+ implementation and again one year following implementation. Following ERAS+ implementation, postoperative pulmonary complications reduced to 24/228 (10.5%). Sustained improvement was evident one year after implementation, with a pulmonary complication rate of 16/183 (8.7%). Median (IQR [range]) length of hospital stay one year after implementation of ERAS+ also improved from 12 (9–15 [4‐101]) to 9 (5.5–10.5 [3‐81]) days. The ERAS+ pathway is applicable to patients undergoing elective major surgery and appears effective in reducing postoperative pulmonary complications.     

Pilot multi‐centre randomised trial of the impact of pre‐operative focused cardiac ultrasound on mortality and morbidity in patients having surgery for femoral neck fractures (ECHONOF‐2 pilot)

Hip fracture surgery is common, usually occurs in elderly patients who have multiple comorbidities, and is associated with high morbidity and mortality. Pre‐operative focused cardiac ultrasound can alter diagnosis and management, but its impact on outcome remains uncertain. This pilot study assessed feasibility and group separation for a proposed large randomised clinical trial of the impact of pre‐operative focused cardiac ultrasound on patient outcome after hip fracture surgery. Adult patients requiring hip fracture surgery in four teaching hospitals in Australia were randomly allocated to receive focused cardiac ultrasound before surgery or not. The primary composite outcome was any death, acute kidney injury, non‐fatal myocardial infarction, cerebrovascular accident, pulmonary embolism or cardiopulmonary arrest within 30 days of surgery. Of the 175 patients screened, 100 were included as trial participants (screening:recruitment ratio 1.7:1), 49 in the ultrasound group and 51 as controls. There was one protocol failure among those recruited. The primary composite outcome occurred in seven of the ultrasound group patients and 12 of the control group patients (relative group separation 39%). Death, acute kidney injury and cerebrovascular accident were recorded, but no cases of myocardial infarction, pulmonary embolism or cardiopulmonary arrest ocurred. Focused cardiac ultrasound altered the management of 17 participants, suggesting an effect mechanism. This pilot study demonstrated that enrolment and the protocol are feasible, that the primary composite outcome is appropriate, and that there is a treatment effect favouring focused cardiac ultrasound – and therefore supports a large randomised clinical trial.     

Pre‐operative radiotherapy for rectal carcinoma? Has the case really been made for short course pre‐operative radiotherapy if surgical standards for rectal carcinoma are optimal?

Recent publications on early results of the Dutch trial on pre‐operative radiotherapy combined with total mesorectal excision (TME) for resectable rectal cancer have initiated a major swing towards routine radiotherapy of this type. However, detailed analysis of the data so far published shows 23.3% microscopic margin involvement and 23.9% macroscopically poor specimens in a sample group. Since only mobile tumours were selected these figures are too high to validate the claim that the whole series represents ‘standardized TME surgery’. The role of pre‐operative radiotherapy for resectable rectal cancer undergoing optimal surgery therefore remains open. It may be expected that in future the individual indication for pre‐operative radiotherapy will be based on the findings of pre‐operative modern fine slice high resolution magnetic resonance imaging (MRI).     

A randomised controlled trial examining the effect of acupuncture at the EX‐HN3 (Yintang) point on pre‐operative anxiety levels in neurosurgical patients

Pre‐operative anxiety is an unpleasant state of psychological distress that occurs in up to 87% of patients awaiting neurosurgical procedures. Sedative medication is undesirable in this population due to the need for early postoperative neurological assessment. Acupuncture has previously been shown to reduce pre‐operative anxiety, but studies involving neurosurgical patients are lacking. This single‐centre, prospective, randomised controlled trial was designed to determine the effect of acupuncture at the EX‐HN3 (Yintang point) on pre‐operative anxiety levels in neurosurgical patients. The study was prospectively registered before participant recruitment. After measuring baseline anxiety levels, 128 patients were randomly allocated in a 1:1 ratio by a web‐based computer program to receive either acupuncture at the EX‐HN3 (Yintang) point (acupuncture group) or no intervention (control group). Participants were not blinded, but all analyses were performed by a member of the research team who was unaware of the group allocation. The primary outcome measure was anxiety level after 30 min, as measured by the six‐item short form of the State‐Trait Anxiety Inventory (possible score range 20–80). Sixty‐two patients in each group were subsequently analysed. Median (IQR [range]) anxiety State‐Trait Anxiety Inventory score reduced significantly in the acupuncture group (46.7 (36.7–53.3 [23.3–70.0]) to 40.0 (30.0–46.7) [20.0–53.3]), p < 0.001), with no change seen in the control group (41.7 (33.3–53.3 [20.0–76.7]) to 43.3 (36.7–50.0 [20.0–76.7]), p = 0.829). There were no adverse events in either group. Acupuncture at the EX‐HN3 point reduces pre‐operative anxiety levels in patients awaiting neurosurgery.     

Peri‐operative management of anti‐platelet agents

Background: Increasing numbers of patients treated with anti‐platelet agents are presenting for non‐cardiac surgery. We examined the peri‐operative management of anti‐platelet therapy in patients undergoing elective non‐cardiac surgery and the process by which patients received instructions. Methods: We interviewed and collected outcome data on 213 consecutive patients aged ≥45 years presenting for elective non‐cardiac surgery at our institution over a 6‐week period regarding the peri‐operative management of anti‐platelet and warfarin therapy. Results: Anti‐platelet therapy was prescribed in 22.5% and warfarin in 5.2% of the study subjects. Aspirin was stopped peri‐operatively in 55.3%, while clopidogrel was stopped in the sole patient treated with this. The frequency of anti‐platelet agent discontinuation was similar for major and minor surgery. Warfarin was discontinued prior to surgery in all cases. Only 54.2% of those treated with anti‐platelet therapy recalled being given instruction regarding pre‐operative management of their anti‐platelet therapy compared with 90.9% of patients treated with warfarin (P= 0.04). In the absence of instructions, a number of patients made their own decision to stop their aspirin pre‐operatively. Post‐operatively, only 37% recalled receiving instructions regarding restarting anti‐platelet therapy. As a result, three patients failed to do so. In contrast, all those treated with warfarin received clear post‐operative instructions. Conclusion: Peri‐operative anti‐platelet management and communication with patients appears to be sub‐optimal. There is a need for standardized processes whereby informed decisions regarding peri‐operative anti‐platelet therapy are made and communicated clearly to the patients.     

The association of hypotension during non‐cardiac surgery,before and after skin incision,with postoperative acute kidney injury: a retrospective cohort analysis

Intra‐operative hypotension is associated with acute postoperative kidney injury. It is unclear how much hypotension occurs before skin incision compared with after, or whether hypotension in these two periods is similarly associated with postoperative kidney injury. We analysed the association of mean arterial pressure < 65 mmHg with postoperative kidney injury in 42,825 patients who were anaesthetised for elective non‐cardiac surgery. Intra‐operative hypotension occurred in 30,423 (71%) patients: 22,569 (53%) patients before skin incision; and 24,102 (56%) patients after incision. Anaesthetised patients who were hypotensive had mean arterial pressures < 65 mmHg for a median (IQR [range]) of 5.5 (0.0–14.7 [0.0–60.0]) min.h^?1 before skin incision, compared with 1.7 [0.3–5.1 [0.0–57.5]) min.h^?1 after incision: a median (IQR [range]) of 36% (0%–84% [0%–100%]) of hypotensive readings were before incision. We diagnosed postoperative kidney injury in 2328 (5%) patients. The odds ratio (95%CI) for acute kidney injury was 1.05 (1.02–1.07) for each doubling of the duration of hypotension, p < 0.001. Postoperative kidney injury was associated with the product of hypotension duration and severity, that is, area under the curve, before skin incision and after, odds ratio (95%CI): 1.02 (1.01–1.04), p = 0.004; and 1.02 (1.00–1.04), p = 0.016, respectively. A substantial fraction of all hypotension happened before surgical incision and was thus completely due to anaesthetic management. We recommend that anaesthetists should avoid mean arterial pressure < 65 mmHg during surgery, especially after induction, assuming that its association with postoperative kidney injury is, at least in part, causal.