Hypnotic depth and postoperative death: a Bayesian perspective and an Independent Discussion of a clinical trial

Association between sedation during spinal anesthesia and mortality in older patients undergoing hip fracture surgery: A nationwide retrospective cohort study in Japan

STUDY OBJECTIVE

Intraoperative sedation plays an important role in the management of regional anesthesia. Few studies have investigated the association of sedation during spinal anesthesia with postoperative mortality in older patients as a primary outcome. This study aimed to test the hypothesis that sedation during spinal anesthesia increases postoperative mortality in older patients undergoing hip fracture surgery.

DESIGN

Retrospective, cohort study.

SETTING

Acute and subacute care hospitals in Japan.

PATIENTS

Patients aged 65 years and older who received hip fracture surgery under spinal anesthesia between April 2014 and May 2022.

EXPOSURE

Sedation during spinal anesthesia.

MEASUREMENTS

Postoperative in-hospital all-cause mortality within 30 days.

MAIN RESULTS

In total, 25,554 eligible patients were identified. Propensity score matching created 4735 pairs, and baseline patient characteristics were acceptably balanced between the sedation and non-sedation groups. There was no significant difference in 30-day postoperative mortality between the two groups (hazard ratio [95% CIs]: 0.92 [0.59-1.44]).

CONCLUSIONS

There was no association between sedation during hip fracture surgery in older patients under spinal anesthesia and postoperative mortality. However, these results are limited to our population, and further prospective studies are needed to determine the safety of sedation.

Antegrade administration of mitomycin gel for upper tract urothelial carcinoma via percutaneous nephrostomy tube: a multi-institutional retrospective cohort study

OBJECTIVES

To assess the safety profile of antegrade mitomycin gel instillation through a percutaneous nephrostomy tube (PCNT) for upper tract urothelial carcinoma (UTUC) with the aim of decreasing morbidity associated with therapy.

PATIENTS AND METHODS

Patients undergoing antegrade administration of mitomycin gel via PCNT were retrospectively included for analysis from four tertiary referral centres between 2020 and 2022. The primary outcome was safety profile, as graded by Common Terminology Criteria for Adverse Events (v5.0). Post-therapy disease burden was assessed by primary disease evaluation (PDE) via ureteroscopy.

RESULTS

Thirty-two patients received at least one dose of mitomycin gel via PCNT for UTUC, 29 of whom completed induction and underwent PDE. Thirteen patients (41%) had residual tumour present prior to induction therapy. At a median of 15.0 months following first dose of induction therapy, ureteric stenosis occurred in three patients (9%), all of whom were treated without later recurrence or chronic stenosis. Other adverse events included fatigue (27%), flank pain (19%), urinary tract infection (12%), sepsis (8%) and haematuria (8%). No patients had impaired renal function during follow-up and there were no treatment-related deaths. Seventeen patients (59%) had no evidence of disease at PDE and have not experienced recurrence at a median follow-up of 13.0 months post induction.

CONCLUSIONS

Administration of mitomycin gel via a PCNT offers a low rate of ureteric stenosis, demonstrates a favourable safety profile, and is administered without general anaesthesia.

Depth of anaesthesia and mortality after cardiac or noncardiac surgery: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Recent randomised controlled trials have failed to show a benefit in mortality by using processed electroencephalography (pEEG) to guide lighter anaesthesia. We performed a meta-analysis of mortality data from randomised trials of pEEG monitoring to assess the evidence of any protective effect of pEEG-guided light anaesthesia compared with deep anaesthesia in adults aged ≥18 yr.

METHODS

Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. In February 2022, we searched three databases (Cochrane CENTRAL, OVID Medline, EMBASE) for RCTs of pEEG monitoring that provided mortality data at 30 days, 90 days, and/or 1 yr or longer.

RESULTS

We included 16 articles from 12 RCTs with 48 827 total participants. We observed no statistically significant mortality reduction with light anaesthesia compared with deep anaesthesia in patients aged ≥18 yr when all studies were pooled (odds ratio [OR]=0.99; 95% confidence interval (CI), 0.92-1.08). This result did not change significantly when analysing mortality at 30 days, 90 days, 1 yr or longer. We observed no mortality benefit for pEEG monitoring compared with usual care (OR=1.02; 95% CI, 0.89-1.18), targeting higher pEEG index values compared with lower values (OR=0.89; 95% CI, 0.60-1.32), or low pEEG index value alerts compared with no alerts (OR=1.02; 95% CI, 0.41-2.52).

CONCLUSIONS

pEEG-guided lighter anaesthesia does not appear to reduce the risk of postoperative mortality. The absence of a plausible rationale for why deeper anaesthesia should increase mortality has hampered appropriate design of definitive clinical trials.

CLINICAL TRIAL REGISTRATION

CRD42022285195 (PROSPERO).

General anesthetic techniques for enhanced recovery after surgery: Current controversies

General anesthesia technique can influence not only immediate postoperative outcomes, but also long-term outcomes beyond hospital stay (e.g., readmission after discharge from hospital). There is lack of evidence regarding superiority of total intravenous anesthesia over inhalation anesthesia with regards to postoperative outcomes even in high-risk population including cancer patients. Optimal balanced general anesthetic technique for enhance recovery after elective surgery in adults includes avoidance of routine use preoperative midazolam, avoidance of deep anesthesia, use of opioid-sparing approach, and minimization of neuromuscular blocking agents and appropriate reversal of residual paralysis. Given that the residual effects of drugs used during anesthesia can increase postoperative morbidity and delay recovery, it is prudent to use a minimal number of drug combinations, and the drugs used are shorter-acting and administered at the lowest possible dose. It is imperative that the discerning anesthesiologist consider whether each drug used is really necessary for accomplishing perioperative goals.

Effect of electroencephalogram-guided anaesthesia administration on 1 yr mortality: 1 yr follow-up of a randomised clinical trial

BACKGROUND

Intraoperative EEG suppression duration has been associated with postoperative delirium and mortality. In a clinical trial testing anaesthesia titration to avoid EEG suppression, the intervention did not decrease the incidence of postoperative delirium, but was associated with reduced 30 day mortality. The present study evaluated whether the EEG-guided anaesthesia intervention continued to be associated with reduced 1 yr mortality.

METHODS

This manuscript reports 1 yr follow-up of patients from a single-centre RCT, including a post-hoc secondary outcome (1 yr mortality) in addition to pre-specified secondary outcomes. The trial included patients aged 60 yr or older undergoing surgery with general anaesthesia between January 2015 and May 2018. Patients were randomised to receive EEG-guided anaesthesia or usual care. The previously reported primary outcome was postoperative delirium. The outcome of the current study was all-cause 1 yr mortality.

RESULTS

Of the 1232 patients enrolled, 614 patients were randomised to EEG-guided anaesthesia and 618 patients to usual care. One year mortality was 57/591 (9.6%) in the guided group and 62/601 (10.3%) in the usual-care group. No significant difference in mortality was observed (adjusted absolute risk difference, -0.7%; 99.5% confidence interval, -5.8% to 4.3%; P=0.68).

CONCLUSIONS

An EEG-guided anaesthesia intervention aiming to decrease duration of EEG suppression during surgery did not significantly decrease 1 yr mortality. These findings, in the context of other studies, do not provide supportive evidence for EEG-guided anaesthesia to prevent intermediate term postoperative death.

CLINICAL TRIAL REGISTRATION

NCT02241655.

The cumulative duration of bispectral index less than 40 concurrent with hypotension is associated with 90-day postoperative mortality: a retrospective study

BACKGROUND

The relationship between intraoperative low bispectral index (BIS) values and poor clinical outcomes has been controversial. Intraoperative hypotension is associated with postoperative complication. The purpose of this study was to investigate the influence of intraoperative low BIS values and hypotension on postoperative mortality in patients undergoing major abdominal surgery.

METHODS

This retrospective study analyzed 1862 cases of general anesthesia. We collected the cumulative time of BIS values below 20 and 40 as well as electroencephalographic suppression and documented the incidences in which these states were maintained for at least 5 min. Durations of intraoperative mean arterial pressures (MAP) less than 50 mmHg were also recorded. Multivariable logistic regression was used to evaluate the association between suspected risk factors and postoperative mortality.

RESULTS

Ninety-day mortality and 180-day mortality were 1.5 and 3.2% respectively. The cumulative time in minutes for BIS values falling below 40 coupled with MAP falling below 50 mmHg was associated with 90-day mortality (odds ratio, 1.26; 95% confidence interval, 1.04-1.53; P = .019). We found no association between BIS related values and 180-day mortality.

CONCLUSIONS

The cumulative duration of BIS values less than 40 concurrent with MAP less than 50 mmHg was associated with 90-day postoperative mortality, not 180-day postoperative mortality.