Reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia: a review.

BACKGROUND: Intraoperative hypotension (IOH) during non-cardiac surgery is common and associated with major adverse kidney, neurological and cardiac events and even death. Given that IOH is a modifiable risk factor for the mitigation of postoperative complications, it is imperative to generate a precise definition for IOH to facilitate strategies for avoiding or treating its occurrence. Moreover, a universal and consensus definition of IOH may also facilitate the application of novel and emerging therapeutic interventions in treating IOH. We conducted a review to systematically record the reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia. METHODS: In accordance with Cochrane guidelines, we searched three online databases (OVID [Medline], Embase and Cochrane Library) for all studies published from 1 January 2000 to 6 September 2020. We evaluated the number of studies that reported the absolute or relative threshold values for defining blood pressure. Secondary aims included evaluation of the threshold values for defining IOH, the methodology for accounting for the severity of hypotension, whether the type of surgical procedure influenced the definition of IOH, and whether a study whose definition of IOH aligned with the Perioperative Quality Initiative-3 workgroup (POQI) consensus statement for defining was more likely to be associated with determining an adverse postoperative outcome. RESULTS: A total of 318 studies were included in the final qualitative synthesis. Most studies (n = 249; 78.3%) used an absolute threshold to define hypotension; 150 (60.5%) reported SBP, 117 (47.2%) reported MAP, and 12 (4.8%) reported diastolic blood pressure (DBP). 126 (39.6%) used a relative threshold to define hypotension. Of the included studies, 153 (48.1%) did not include any duration variable in their definition of hypotension. Among the selected 318 studies 148 (46.5%) studies defined IOH according to the POQI statement. When studies used a "relative blood pressure change" to define IOH, there was a weaker association in detecting adverse postoperative outcomes compared to studies who reported "absolute blood pressure change" (χ2(2) = 10.508, P = 0.005, Cramér's V = 0.182). When studies used the POQI statement definition of hypotension or defined IOH by values higher than the POQI statement definition there were statistical differences observed between IOH and adverse postoperative outcomes (χ2(1) = 6.581, P = 0.037, Cramér's V = 0.144). When both the duration of IOH or the numbers of hypotensive epochs were evaluated, we observed a significantly stronger relationship between the definition of IOH use the development of adverse postoperative outcomes. (χ2(1) = 4.860, P = 0.027, Cramér's V = 0.124). CONCLUSIONS: Most studies defined IOH by absolute or relative changes from baseline values. There are substantial inconsistencies in how IOH was reported. Further, definitions differed across different surgical specialities. Our findings further suggest that IOH should be defined using the absolute values stated in the POQI statement i.e., MAP < 60-70 mmHg or SBP < 100 mmHg. Finally, the number of hypotensive epochs or time-weighted duration of IOH should also be reported.

MEasuring the impact of Anesthetist-administered medications volumeS on intraoperative flUid balance duRing prolonged abdominal surgEry (MEASURE Study).

BACKGROUND: The contribution of intraoperative anesthetist-administered medications (IAAMs) to the total volume of intraoperative intravenous (IV) fluid therapy and their association with postoperative outcomes has never been formally investigated. METHODS: We performed a retrospective study of adult patients undergoing pancreaticoduodenectomy. The volume of IAAMs, crystalloids and colloids, blood and blood products, blood loss, urine output and intraoperative fluid balance were collected. The contribution of IAAMs to the total intraoperative IV fluid volume and postoperative complications was evaluated. RESULTS: A total of 152 consecutive patients were included. The median volume of IAAMs was 363.8 mL (interquartile range [IQR], (241.0-492.5) delivered at a median rate of 0.61 mL kg hr-1 (0.40-0.87) over a median duration of surgery of 489 minutes (416.3-605.3). This increased the total administered fluid volume by 5.2% (95% confidence intervals [CI]: 4.6, 5.9%) (Cohen's d=1.33, P<0.001). The volume of IAAMs was comparable to the intraoperative colloid volume administered (median colloid volume, 400 mL). Overall, fluid volumes correlated significantly with the severity of complications (P=0.011), and the correlation strength increased when the IAAMs volume was included (P=0.005). On addition of IAAMs, the area under the receiver operator characteristic curve for prediction of postoperative complications increased from 0.580 (95%CI: 0.458, 0.701) to 0.603 (95%CI: 0.483, 0.723), P=0.041). CONCLUSIONS: IAAMs significantly increased the total administered fluid volume during pancreaticoduodenectomy. Their inclusion increases the accuracy of postoperative complications predictions. These findings support their inclusion in fluid volumes and balances in future interventional studies.

Characteristics, comorbidity burden and outcomes in centenarians undergoing surgery in a university hospital: A case series.

INTRODUCTION: As the population ages, so too does the age of those requiring surgery. People over the age of 100, centenarians, often have a greater degree of comorbidity and frailty than their younger counterparts but may also have a greater incidence of events requiring surgical intervention. There is, however, a dearth of literature describing the clinical course and practical considerations for this vulnerable population undergoing surgery. We aimed to describe the demographics of centenarians undergoing surgery, the procedures they receive, their intraoperative anaesthesia management, and their postoperative outcomes. PRESENTATION OF CASES: A retrospective cohort study was completed to understand key perioperative and intraoperative variables linked to improved outcomes. Of the 25 patients included in this study, 22 (88%) were female and the median age was 101 years. Emergency cases predominated (72%) and 44% of surgeries occurred after hours. 60% underwent an intermediate risk surgery, and no centenarians underwent high risk surgery in this study period. DISCUSSION: 64% of patients experienced at least one episode of intraoperative hypotension, with a median 3.5 epochs per patient. 68% of patients experienced postoperative complications and 20% of patients had a complication of Clavien-Dindo severity ≥ III. In centenarians, the risk of high severity postoperative complications was independent of the intrinsic procedural risk. CONCLUSION: Centenarian patients have an elevated burden of comorbidity, presenting often in the emergent setting. However, age alone should not preclude surgical intervention as expert multidisciplinary care can have acceptable outcomes.

A spontaneous retroperitoneal haemorrhage resulting in abdominal compartment syndrome requiring laparotomy: A case report and proposed management algorithm.

INTRODUCTION AND IMPORTANCE: Spontaneous Retroperitoneal Haemorrhage (SRH) is a rare condition, which in its extreme state can result in Abdominal Compartment Syndrome (ACS). The aim of this case report is to provide an overview of the diagnosis and management of SRH and to present an algorithm to inform and guide clinical decision-making in the context of ACS. CASE PRESENTATION: A 74-year-old woman with multiple risk factors for SRH developed a tense abdomen in ICU post-cardiac graft study. Radiological imaging confirmed multiple bleeding points to the contralateral side of the graft access site. She underwent endovascular treatment for her condition, however, developed ACS necessitating surgical evacuation of the haematoma. CLINICAL DISCUSSION: SRH is a rare condition that may be difficult to diagnose on physical exam. Medical, endovascular and surgical approaches are recognised treatments. ACS is an extreme variant of SRH and although endovascular management can specifically address the acute bleed, surgical evacuation of the haematoma is the only treatment that can effectively reduce abdominal compartment pressures. CONCLUSION: SRH can cause abdominal compartment syndrome with subsequent multiorgan failure. Ultimately, as outlined in this case, surgical evacuation of the haematoma was the only treatment able to reduce abdominal compartment pressures.

Improving emergency surgical care for patients with right iliac fossa pain at a regional scale: A quality improvement study using the Supported Champions implementation strategy.

INTRODUCTION: Methods to improve clinical systems safety suffer from significant difficulties in implementation and scaling up. We used an upscaling implementation strategy entitled Supported Champions in a quality and safety improvement programme for emergency surgery at regional level, focusing on patients with right iliac fossa pain. METHODS: A before-after study was conducted across four acute NHS Trusts: A 6 month intervention phase was preceded and followed by 3 months of data collection. An established Human Factors intervention was led at each Trust by a small group of staff selected as Champions. Champions received training in teamwork and systems improvement and were supported by Human Factors experts. The primary improvement aim was to expedite surgery for patients with sepsis, using Royal College of Surgeons emergency surgery guidelines as the measure. Additional outcomes studied included length of inpatient stay and 30-day readmission rates. RESULTS: Breaches of RCS urgency guidelines decreased markedly from 13.7% of operated patients pre-intervention to 3.5% post-intervention (p = 0.000). Mean time from booking to incision decreased in three of the four sites, whilst median length of stay increased in 3 of 4. Overall 30-day readmission rate remained stable (7.84% pre-intervention versus 7.31% post-intervention, p = 0.959). DISCUSSION: The Supported Champions model allowed all surgical teams to reduce delay for septic patients by more than 50%, using distinct Quality Improvement strategies to address local issues. Improvement was implemented in 4 diverse settings with a quarter of the level of expert input previously used in a single hospital.

Should all paediatric patients with presumed idiopathic scoliosis undergo MRI screening for neuro-axial disease?

BACKGROUND: Idiopathic scoliosis is a relatively common childhood condition affecting 0.47-5.2% of the population. Traditional interventions focus on orthopaedic correction of the curve angle. There is a spectrum of patients with scoliosis who are found to have neuro-axial abnormality on full MRI of the spine, but not all surgeons request imaging in the absence of neurological symptoms. There is evidence to suggest that treatment of neuro-axial disease may improve scoliosis curve outcome. We therefore sought to estimate what proportion of patients with normal neurology and scoliosis are found to have neuro-axial abnormality on full MRI imaging of the spine, in particular Chiari malformation and syringomyelia. RESULTS: Out of 11 identified studies consisting of 3372 paediatric patients (age < 18 years), mean weighted proportion demonstrates that 14.7% of patients with scoliosis (Cobb angle > 20°) and normal neurological examination will demonstrate a neuro-axial abnormality on full MRI imaging of the spine. Of patients, 8.3 and 8.4% were found to have Chiari malformation and syringomyelia, respectively. CONCLUSIONS: Up to one in seven paediatric patients with scoliosis and normal neurological examination will demonstrate neuro-axial disease on MRI imaging of the spine. Given that younger age and earlier age of decompression is associated with improvement in curve angle, it seems important that MRI screening be considered in all patients regardless of neurological examination findings. There is a potentially long-term benefit in these patients. Multi-cross institutional prospective studies are encouraged to further investigate effect on curve angle.

Outcomes after second surgery for recurrent glioblastoma: a retrospective case-control study.

Studies looking at the benefit of surgery at first relapse (second surgery) for recurrent glioblastoma were confounded by including patients with varying grades of glioma, performance status and extent of resection. This case-controlled study aims to remove these confounders to assess the survival impact of second surgery in recurrent glioblastoma. Retrospective data on patients with glioblastoma recurrence at two tertiary Australian hospitals from July 2009 to April 2015 was reviewed. Patients who had surgery at recurrence were matched with those who did not undergo surgery at recurrence, based on the extent of their initial resection and age. Overall survival (OS1 assessed from initial diagnosis and OS2 from the date of recurrence) as well as functional outcomes after resection were analysed. There were 120 patients (60 in each institution); median age at diagnosis was 56 years. Median OS1 was 14 months (95% CI 11.5-15.7) versus 22 months (95% CI 18-25) in patients who did not undergo second surgery and those with surgery at recurrence. OS2 was improved by second surgery (4.7 vs 9.6, HR 0.52, 95% CI 0.38-0.72, P < 0.001), and by chemotherapy, given at recurrence, (HR 0.47, 95% CI 0.24-0.92, P = 0.03). After second surgery, 80% did not require rehabilitation and 61% were independently mobile. Second surgery for recurrent glioblastoma was associated with a survival advantage. Chemotherapy independent of surgery, also improved survival. Functional outcomes were encouraging. More research is required in the era of improved surgical techniques and new antineoplastic therapies.

Reoperation for Recurrent Glioblastoma and Its Association With Survival Benefit.

BACKGROUND: Glioblastoma is the most common and aggressive primary brain tumor. Despite current treatment, recurrence is inevitable. There are no clear guidelines for treatment of recurrent glioblastoma. OBJECTIVE: To investigate factors at initial surgery predictive of reoperation, and the prognostic variables associated with survival, including reoperation for recurrence. METHODS: A retrospective cohort study was performed, including adult patients diagnosed with glioblastoma between January 2010 and December 2013. Student t test and Fisher exact test compared continuous and categorical variables between reoperation and nonreoperation groups. Univariable and Cox regression multivariable analysis was performed. RESULTS: In a cohort of 204 patients with de novo glioblastoma, 49 (24%) received reoperation at recurrence. The median overall survival in the reoperation group was 20.1 months compared with 9.0 months in the nonreoperation group (P = .001). Reoperation was associated with longer overall survival in our total population (hazard ratio, 0.646; 95% confidence interval, 0.543-0.922; P = .016) but subject to selection bias. Subgroup analyses excluding patients unlikely to be considered for reoperation suggested a much less significant effect of reoperation on survival, which warrants further study with larger cohorts. Factors at initial surgery predictive for reoperation were younger age, smaller tumor size, initial extent of resection ≥50%, shorter inpatient stay, and maximal initial adjuvant therapy. When unfavorable patient characteristics are excluded, reoperation is not an independent predictor of survival. CONCLUSION: Patients undergoing reoperation have favorable prognostic characteristics, which may be responsible for the survival difference observed. We recommend that a large clinical registry be developed to better aid consistent and homogenous data collection. ABBREVIATIONS: ECOG, Eastern Cooperative Oncology GroupEOR, extent of resectionIDH-1, isocitrate dehydrogenase 1IP, inpatientMGMT, O-methylguanine methyltransferaseOS, overall survivalPFS, progression-free survivalRMH, Royal Melbourne Hospital.

Cryopreserved embryos and Dignitas personae: another option?

Many of the thousands of human embryos currently in cryogenic storage will sooner or later be discarded, often after being experimented upon. Others will remain in storage indefinitely, left there by parents who have no plans either to bring them to term or to offer them for adoption. These facts, coupled with a commitment to the basic moral equality of all human beings at all stages of development, generate a pressing question: What should be done for these embryos whose vital activities have been suspended and whose futures look so bleak? This paper offers a case that allows some of these cryogenically stored embryos to thaw and die, allows disposal of their remains in a manner that reflects their status, and is morally acceptable in that it is consistent with the principles that many accept as governing the removal of life-sustaining treatment in end-of-life cases.

Researchers and firing squads: questions concerning the use of frozen human embryos.

Is it morally acceptable to use human embryos left over from fertility treatments in research that would harm or destroy them? Many answer "no" to this question on the grounds that all human beings, including human embryos, have a basic moral status that forbids such use. There are some, though, who accept this claim about the basic moral status of human embryos but who believe nevertheless that frozen human embryos which were generated for fertility treatments but which are no longer wanted for that project are a morally acceptable source of human embryonic stem cells and are acceptable subjects of other forms of research that would destroy them in course. The reasoning offered in defense of this position typically employs the claim that since these embryos are going to be discarded anyway, their possibly fruitful use by researchers is a preferable alternative and one that is not inconsistent with their basic moral status. Howard Curzer has offered a well-developed argument of this sort, defending the use of these embryos in the ways mentioned while at the same time allowing for their equal basic moral status. This article challenges Curzer's case and offers reasons to reject the moral acceptability of using even these to-be-discarded embryos as research material.