Perioperative challenges in management of diabetic patients undergoing non-cardiac surgery

Prediabetes and diabetes are important disease processes which have several perioperative implications. About one third of the United States population is considered to have prediabetes. The prevalence in surgical patients is even higher. This is due to the associated micro and macrovascular complications of diabetes that result in the need for subsequent surgical procedures. A careful preoperative evaluation of diabetic patients and patients at risk for prediabetes is essential to reduce perioperative mortality and morbidity. This preoperative evaluation involves an optimization of preoperative comorbidities. It also includes optimization of antidiabetic medication regimens, as the avoidance of unintentional hypoglycemic and hyperglycemic episodes during the perioperative period is crucial. The focus of the perioperative management is to ensure euglycemia and thus improve postoperative outcomes. Therefore, prolonged preoperative fasting should be avoided and close monitoring of blood glucose should be initiated and continued throughout surgery. This can be accomplished with either analysis in blood gas samples, venous phlebotomy or point-of-care testing. Although capillary and arterial whole blood glucose do not meet standard guidelines for glucose testing, they can still be used to guide insulin dosing in the operating room. Intraoperative glycemic control goals may vary slightly in different protocols but overall the guidelines suggest a glucose range in the operating room should be between 140 mg/dL to 180 mg/dL. When hyperglycemia is detected in the operating room, blood glucose management may be initiated with subcutaneous rapid-acting insulin, with intravenous infusion or boluses of regular insulin. Fluid and electrolyte management are other perioperative challenges. Notably diabetic ketoacidosis and hyperglycemic hyperosmolar nonketotic state are the two most serious acute metabolic complications of diabetes that must be recognized early and treated.

Cesarean Delivery in the Bronchoscopy Suite in a Patient with an Anterior Mediastinal Mass

Mediastinal masses pose a significant challenge for anesthesiologists due to the risk of cardiorespiratory collapse. Pregnancy in of itself causes multiple detrimental changes to respiratory physiology. We present a case of cesarean delivery performed in the bronchoscopy suite followed by bronchoscopic airway evaluation in a patient at 33 weeks gestation with symptomatic anterior mediastinal mass. We discuss the multidisciplinary approach and anaesthetic management of this complicated case.

Effects of an Automated External Defibrillator With Additional Video Instructions on the Quality of Cardiopulmonary Resuscitation

Aim of the Study: The aim was to compare cardiopulmonary resuscitation (CPR) quality of an automated external defibrillator (AED) with and without additional video instruction during basic life support (BLS) by laypersons. Methods: First-year medical students were randomized either to an AED with audio only or audio with additional video instructions during CPR. Each student performed 4 min of single-rescuer chest compression only BLS on a manikin (Ambu Man C, Ballerup, Denmark) using the AED. The primary outcome was the effective compression ratio during this scenario. This combined parameter was used to evaluate the quality of chest compressions by multiplying compressions with correct depth, correct hand position, and complete decompression by flow time. Secondary outcomes were percentages of incomplete decompression and hand position, mean compression rate, time-related parameters, and subjective assessments. Results: Effective compression ratio did not differ between study groups in the overall sample (p = 0.337) or in students with (p = 0.953) or without AED experience (p = 0.278). Additional video instruction led to a higher percentage of incorrect decompressions (p = 0.014). No significant differences could be detected in time-related resuscitation parameters. An additional video was subjectively rated as more supporting (p = 0.001). Conclusions: Audio-video instructions did not significantly improve resuscitation quality in these laypersons despite that it was felt more supportive. An additional video to the verbal AED prompts might lead to cognitive overload. Therefore, future studies might target the influence of the video content and the potential benefits of video instructions in specific populations.

Do It Often, Do It Better: Association Between Pairs of Experienced Subspecialty Anesthesia Caregivers and Postoperative Outcomes. A Retrospective Observational Study

BACKGROUND

Anesthesiologists typically care for patients having a broad range of procedures. Outcomes might be improved when care is provided by caregivers experienced in particular types of surgery. We tested the hypothesis that intraoperative care provided by pairs of anesthesia caregivers having significant experience with a particular type of surgery reduces a composite of in-hospital death and 6 serious complications, including bleeding, cardiac, gastrointestinal, infectious, respiratory, and urinary complications, compared to care provided by pairs of anesthesia caregivers with less experience.

METHODS

We included patients having surgery lasting at least 30 minutes. Using cluster analysis, attending anesthesiologists, and Certified Registered Nurse Anesthetists (CRNAs) were identified as experienced or inexperienced caregivers for each type of surgery at the case level. We then compared surgeries for which anesthesia was provided by a pair of experienced caregivers versus a pair of inexperienced caregivers on our composite outcome. We estimated the average relative effect (ie, the exponentiated average log odds ratio) of receiving anesthesia from an experienced versus inexperienced caregiver pair across the 7 components of the composite outcome using a generalized estimating equation (GEE) model to adjust for between-component correlation and with inverse propensity score weighing to adjust for potential confounding from a host of variables.

RESULTS

A total of 8968 patients who received anesthesia care by an experienced pair were compared with 25,361 patients who received care from an inexperienced pair, adjusting for potential confounding. The incidence of composite complications (ie, any component event) was 7.6% (677/8968) for experienced pairs and 12% (2976/25,361) for inexperienced pairs (P < .001). Care by experienced pairs of caregivers was associated with lower odds of the composite outcome with an estimated average relative effect odds ratio across the individual components of 0.61 (95% confidence interval [CI], 0.54-0.71), P < .001. Among the 7 components of the primary outcome, experienced pairs of providers had significantly lower estimated odds of bleeding, infection, and mortality.

CONCLUSIONS

Anesthesia care by experienced pairs was associated with fewer bleeding complications, fewer infections, shorter hospitalization, and reduced in-hospital mortality.

How the COVID-19 pandemic changed treatment of severe aortic stenosis: a single cardiac center experience

Background

Currently, two effective therapeutic options for severe aortic stenosis (AS) are available, one catheter-based [transcatheter aortic valve implantation (TAVI)], the other open surgical approach [surgical aortic valve replacement (SAVR)]. The COVID-19 pandemic has limited the availability of medical procedures. The purpose of this cross-sectional study was to assess if this pandemic had any impact on the treatment strategy of severe AS in a single cardiac center.

Methods

This study involved AS patients treated in 3-month periods (February through April) over 3 consecutive years 2018, 2019 [defined as COV(-) group] and 2020 [COV(+)]. We assessed if there were any differences regarding patients' clinical profile, applied therapeutic method, procedure complexity and early clinical outcomes.

Results

In the years 2018 through 2019, approximately 50% of AS patients were treated classically (SAVR) while in 2020 this rate dropped to 34%. The preoperative clinical characteristic of TAVI subjects was comparable irrespective of the year. Regarding SAVR, more patients in COV(+) underwent urgent and more complex procedures. More of them were found in NYHA class III or IV, and had lower left ventricular ejection fraction (LVEF) (51.9%±14.4% vs. 58.3%±8.1%; P=0.021) than in COV(-) individuals. During the pandemic, a change in applied therapeutic methods and differences in patients' clinical profile did not have an unfavorable impact on in-hospital mortality (2.0% before vs. 3.6% during pandemic) and morbidity. Of note, intubation time and in-hospital stay were significantly shorter (P<0.05) in 2020 (4.2 hours and 7.5 days) than in the previous years (7.5 hours and 9.0 days, respectively).

Conclusions

The coronavirus pandemic has changed substantially the management of severe AS. The shift into less invasive treatment method of AS patients resulted in shortening of in-hospital stay without compromise of short-term outcomes.

Intraosseous versus intravenous access while wearing personal protective equipment: a meta-analysis in the era of COVID-19

BACKGROUND

Obtaining vascular access is one of the key procedures performed in patients in emergency settings.

AIMS

The study was conducted as a meta‑analysis and a systematic review and aimed to address the following question: which intravascular access method should be used in patients with COVID‑19 when wearing full personal protective equipment (PPE)?

METHODS

We performed a systematic search of PubMed, EMBASE, and CENTRAL databases for randomized controlled trials that compared intravascular access methods used by operators wearing full level C PPE. We evaluated procedure duration and the success rate of intraosseous and peripheral intravenous accesses.

RESULTS

Eight randomized controlled trials were included in quantitative synthesis. The use of PPE during intravascular access procedures had an impact on procedure duration in the case of intraosseous access (mean difference [MD], 11.69; 95% CI, 6.47-16.92; P <0.001), as well as reduced the success rate of intraosseous access by 0.8% and intravenous access by 10.1%. Under PPE conditions, intraosseous access, compared with peripheral intravenous access, offered a shorter procedure time (MD, -41.43; 95% CI, -62.36 to -24.47; P <0.001).

CONCLUSION

This comprehensive meta‑analysis suggested that the use of PPE significantly extends the duration of intravascular procedures. However, under PPE conditions, operators were able to obtain intraosseous access in a shorter time and with a higher success rate than in the case of intravenous access.

An optimal chest compression technique using personal protective equipment during resuscitation in the COVID-19 pandemic: a randomized crossover simulation study

BACKGROUND

Cardiopulmonary resuscitation with the use of personal protective equipment (PPE) for aerosol generating procedures (AGP) in patients with suspected or confirmed coronavirus disease 2019 (COVID‑19) remains challenging.

AIMS

The aim of this study was to compare 3 chest compression (CC) methods used by paramedics wearing PPE.

METHODS

The single‑blinded, multicenter, randomized, crossover simulation study involved 67 paramedics wearing PPE AGP. They performed 2‑minute continuous CCs in an adult with suspected or confirmed COVID‑19 in 3 scenarios: 1) manual CCs; 2) CCs with the TrueCPR feedback device; 3) CCs with the LUCAS 3 mechanical CC device.

RESULTS

The depth of CC was more frequently correct when using LUCAS 3 compared with TrueCPR and manual CC (median [IQR] 51 [50-55] mm vs 47 [43-52] mm vs 43 [38-46] mm; P = 0.005). This was also true for the CC rate (median [IQR]102 [100-102] compressions per minute [CPM] vs 105 [98-1114] CPM vs 116 [112-129] CPM; P = 0.027) and chest recoil (median [IQR]100% [98%-100%] vs 83% [60%-92%] vs 39% [25%-50%]; P = 0.001). A detailed analysis of 2‑minute resuscitation with manual CCs showed a decrease in compression depth and full chest recoil after 1 minute of CCs.

CONCLUSION

We demonstrated that during simulated resuscitation with the use of PPE AGP in patients with suspected or confirmed COVID‑19, CC with LUCAS 3 compared with manual CCs as well as the TrueCPR essentially increased the CC quality. In the case of manual CCs by paramedics dressed in PPE AGP, it is advisable to change the person performing resuscitation every minute.

Association between postoperative haemoglobin and myocardial injury after noncardiac surgery: a retrospective cohort analysis

BACKGROUND

Myocardial injury after noncardiac surgery (MINS) is common, mostly silent, and a strong predictor of postoperative mortality. MINS appears to result from myocardial supply-demand mismatch. Recent data support restrictive perioperative transfusion strategies that can result in low postoperative haemoglobin concentrations. Whether low postoperative haemoglobin is associated with myocardial injury remains unknown. We therefore tested the hypothesis that anaemia is associated with an increased risk of myocardial injury in adults having noncardiac surgery.

METHODS

We conducted a retrospective analysis of adults ≥45 yr old who had routine postoperative troponin T (TnT) monitoring after noncardiac surgery at the Cleverland Clinic (including those enrolled in the PeriOperative ISchemic Evaluation-2 Trial [POISE-2], the Safety of Addition of Nitrous Oxide to General Anaesthesia in At-risk Patients Having Major Non-cardiac Surgery [ENIGMA-II], Vascular Events In Noncardiac Surgery Patients Cohort Evaluation Study [VISION], and Anaesthetic Depth and Complications After Major Surgery [BALANCED] trial). Patients with baseline increase in TnT and non-ischaemic aetiologies for TnT increase were excluded. The association between postoperative haemoglobin concentration during the 3 initial postoperative days and the incidence of MINS (fourth-generation TnT ≥0.03 ng ml^-1 judged as attributable to ischaemia) was assessed using a time-varying covariate Cox proportional hazards survival analysis.

RESULTS

Among 6141 patients, 4480 were analysed. The incidence of MINS was 155/4480 (3.5%), ranging from 0/345 (0%) among patients whose lowest postoperative haemoglobin exceeded 13 g dl^-1 to 52/611 (8.5%) in patients whose minimum postoperative haemoglobin was <8 g dl^-1. The confounder-adjusted hazard ratio [95% confidence interval] for having MINS was 1.29 [1.16-1.42] for every 1 g dl^-1 decrease in postoperative haemoglobin in a time-varying covariate analysis. Similar associations were identified in sensitivity analyses.

CONCLUSION

Lower postoperative haemoglobin values are associated with MINS. Whether this association is modifiable by prevention or treatment of anaemia remains to be determined.

McGrath Video Laryngoscope Versus Macintosh Direct Laryngoscopy for Intubation of Morbidly Obese Patients: A Randomized Trial

BACKGROUND

Two-thirds of the US population is considered obese and about 8% morbidly obese. Obese patients may present a unique challenge to anesthesia clinicians in airway management. Videolaryngoscopes may provide better airway visualization, which theoretically improves intubation success. However, previous work in morbidly obese patients was limited. We therefore tested the primary hypothesis that the use of McGrath video laryngoscope improves visualization of the vocal cords versus Macintosh direct laryngoscopy (Teleflex, Morrisville, NC) in morbidly obese patients.

METHODS

We enrolled 130 surgical patients, aged 18-99 years, with a body mass index ≥40 kg/m and American Society of Anaesthesiologists (ASA) physical status I-III. Patients were randomly allocated 1:1-stratified for patient's body mass index ≥50 kg/m-to McGrath video laryngoscope versus direct laryngoscopy with a Macintosh blade. The study groups were compared on glottis visualization, defined as improved Cormack and Lehane classification, with proportional odds logistic regression model.

RESULTS

McGrath video laryngoscope provided significantly better glottis visualization than Macintosh direct laryngoscopy with an estimated odds ratio of 4.6 (95% confidence interval [CI], 2.2-9.8; P < .01). We did not observe any evidence that number of intubation attempts and failed intubations increased or decreased.

CONCLUSIONS

McGrath video laryngoscope improves glottis visualization versus Macintosh direct laryngoscopy in morbidly obese patients. Large clinical trials are needed to determine whether improved airway visualization with videolaryngoscopy reduces intubation attempts and failures.

Myocardial Injury After Noncardiac Surgery: Preoperative, Intraoperative, and Postoperative Aspects, Implications, and Directions

Myocardial injury after noncardiac surgery (MINS) differs from myocardial infarction in being defined by troponin elevation apparently from cardiac ischemia with or without signs and symptoms. Such myocardial injury is common, silent, and strongly associated with mortality. MINS is usually asymptomatic and only detected by routine troponin monitoring. There is currently no known safe and effective prophylaxis for perioperative myocardial injury. However, appropriate preoperative screening may help guide proactive postoperative preventative actions. Intraoperative hypotension is associated with myocardial injury, acute kidney injury, and death. Hypotension is common and largely undetected in the postoperative general care floor setting, and independently associated with myocardial injury and mortality. Critical care patients are especially sensitive to hypotension, and the risk appears to be present at blood pressures previously regarded as normal. Tachycardia appears to be less important. Available information suggests that clinicians would be prudent to avoid perioperative hypotension.

Effect of Intravenous Acetaminophen on Postoperative Hypoxemia After Abdominal Surgery: The FACTOR Randomized Clinical Trial

IMPORTANCE

Opioid-induced ventilatory depression and hypoxemia is common, severe, and often unrecognized in postoperative patients. To the extent that nonopioid analgesics reduce opioid consumption, they may decrease postoperative hypoxemia.

OBJECTIVE

To test the hypothesis that duration of hypoxemia is less in patients given intravenous acetaminophen than those given placebo.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, placebo-controlled, double-blind trial conducted at 2 US academic hospitals among 570 patients who were undergoing abdominal surgery, enrolled from February 2015 through October 2018 and followed up until February 2019.

INTERVENTIONS

Participants were randomized to receive either intravenous acetaminophen, 1 g (n = 289), or normal saline placebo (n = 291) starting at the beginning of surgery and repeated every 6 hours until 48 postoperative hours or hospital discharge, whichever occurred first.

MAIN OUTCOMES AND MEASURES

The primary outcome was the total duration of hypoxemia (hemoglobin oxygen saturation [Spo2] <90%) per hour, with oxygen saturation measured continuously for 48 postoperative hours. Secondary outcomes were postoperative opioid consumption, pain (0- 10-point scale; 0: no pain; 10: the most pain imaginable), nausea and vomiting, sedation, minimal alveolar concentration of volatile anesthetic, fatigue, active time, and respiratory function.

RESULTS

Among 580 patients randomized (mean age, 49 years; 48% women), 570 (98%) completed the trial. The primary outcome, median duration with Spo2 of less than 90%, was 0.7 (interquartile range [IQR], 0.1-5.1) minutes per hour among patients in the acetaminophen group and 1.1 (IQR, 0.1-6.6) minutes per hour among patients in the placebo group (P = .29), with an estimated median difference of -0.04 (95% CI,-0.18 to 0.11) minutes per hour. None of the 8 secondary end points differed significantly between the acetaminophen and placebo groups. Mean pain scores within initial 48 postoperative hours were 4.2 (SD, 1.8) in the acetaminophen group and 4.4 (SD, 1.8) in the placebo group (difference, -0.28; 95% CI, -0.71 to 0.15); median opioid use in morphine equivalents was 50 mg (IQR, 18-122 mg) and 58 mg (IQR, 24-151 mg) , respectively, with a ratio of geometric means of 0.86 (95% CI, 0.61-1.21).

CONCLUSIONS AND RELEVANCE

Among patients who underwent abdominal surgery, use of postoperative intravenous acetaminophen, compared with placebo, did not significantly reduce the duration of postoperative hypoxemia over 48 hours. The study findings do not support the use of intravenous acetaminophen for this purpose.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02156154.

Dexmedetomidine for reduction of atrial fibrillation and delirium after cardiac surgery (DECADE): a randomised placebo-controlled trial

BACKGROUND

Atrial fibrillation and delirium are common consequences of cardiac surgery. Dexmedetomidine has unique properties as sedative agent and might reduce the risk of each complication. This study coprimarily aimed to establish whether dexmedetomidine reduces the incidence of new-onset atrial fibrillation and the incidence of delirium.

METHODS

A randomised, placebo-controlled trial was done at six academic hospitals in the USA. Patients who had had cardiac surgery with cardiopulmonary bypass were enrolled. Patients were randomly assigned 1:1, stratified by site, to dexmedetomidine or normal saline placebo. Randomisation was computer generated with random permuted block size 2 and 4, and allocation was concealed by a web-based system. Patients, caregivers, and evaluators were all masked to treatment. The study drug was prepared by the pharmacy or an otherwise uninvolved research associate so that investigators and clinicians were fully masked to allocation. Participants were given either dexmedetomidine infusion or saline placebo started before the surgical incision at a rate of 0·1 μg/kg per h then increased to 0·2 μg/kg per h at the end of bypass, and postoperatively increased to 0·4 μg/kg per h, which was maintained until 24 h. The coprimary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. All analyses were intention-to-treat. The trial is registered with ClinicalTrials.gov, NCT02004613 and is closed.

FINDINGS

798 patients of 3357 screened were enrolled from April 17, 2013, to Dec 6, 2018. The trial was stopped per protocol after the last designated interim analysis. Among 798 patients randomly assigned, 794 were analysed, with 400 assigned to dexmedetomidine and 398 assigned to placebo. The incidence of atrial fibrillation was 121 (30%) in 397 patients given dexmedetomidine and 134 (34%) in 395 patients given placebo, a difference that was not significant: relative risk 0·90 (97·8% CI 0·72, 1·15; p=0·34). The incidence of delirium was non-significantly increased from 12% in patients given placebo to 17% in those given dexmedetomidine: 1·48 (97·8% CI 0·99-2·23). Safety outcomes were clinically important bradycardia (requiring treatment) and hypotension, myocardial infarction, stroke, surgical site infection, pulmonary embolism, deep venous thrombosis, and death. 21 (5%) of 394 patients given dexmedetomidine and 8 (2%) of 396 patients given placebo, had a serious adverse event as determined by clinicians. 1 (<1%) of 391 patients given dexmedetomidine and 1 (<1%) of 387 patients given placebo died.

INTERPRETATION

Dexmedetomidine infusion, initiated at anaesthetic induction and continued for 24 h, did not decrease postoperative atrial arrhythmias or delirium in patients recovering from cardiac surgery. Dexmedetomidine should not be infused to reduce atrial fibrillation or delirium in patients having cardiac surgery.

FUNDING

Hospira Pharmaceuticals.

Novel airway device Vie Scope in several pediatric airway scenario: A randomized simulation pilot trial

CONTEXT

Endotracheal intubation of pediatric patients is challenging, especially in the pre-hospital emergency setting and if performed by less experienced providers. Securing an airway should be achieved with a single intubation attempt, as each intubation attempt contributes to morbidity and mortality. A new airway device, the VieScope, was recently introduced into clinical market, but efficacy to reduced intubation attempts remains unclear thus far.

OBJECTIVE

We aimed to compare endotracheal intubation by paramedics using the Vie Scope in different pediatric airway simulation conditions.

METHODS

We conducted a randomized, cross-over simulation study. Following a theoretical and practical training session, paramedics performed endotracheal intubation in 3 different pediatric emergency scenarios: normal airway; tongue edema; cardiopulmonary resuscitation using the VieScope. Overall intubation success rate was the primary outcome. Secondary outcomes included number of intubation attempts, time to intubation, Cormack-Lehane grade, POGO score, and ease of use (using 1-100 scale).

RESULTS

Fifty-five paramedics with at least 2 years of clinical experience and without any previous experience with the VieScope participated in this study. The overall intubation success rate was 100% in all 3 scenarios. The median intubation time was 27 (24-34) versus 27 (25-37) versus 29 (25-40) s for scenarios A, B, and C, respectively. In scenario A, all paramedics performed successful intubation with 1 single intubation attempt, whereas 2% of the paramedics had to perform 2 intubation attempts in scenario B and 9% in scenario C.

CONCLUSIONS

Results of this simulation study indicate preliminary evidence, that the VieScope enables adequate endotracheal intubation in the pediatric setting. Further clinical studies are needed to confirm these results.

Resuscitation of the patient with suspected/confirmed COVID-19 when wearing personal protective equipment: A randomized multicenter crossover simulation trial

BACKGROUND

The aim of the study was to evaluate various methods of chest compressions in patients with suspected/confirmed SARS-CoV-2 infection conducted by medical students wearing full personal protective equipment (PPE) for aerosol generating procedures (AGP).

METHODS

This was prospective, randomized, multicenter, single-blinded, crossover simulation trial. Thirty-five medical students after an advanced cardiovascular life support course, which included performing 2-min continuous chest compression scenarios using three methods: (A) manual chest compression (CC), (B) compression with CPRMeter, (C) compression with LifeLine ARM device. During resuscitation they are wearing full personal protective equipment for aerosol generating procedures.

RESULTS

The median chest compression depth using manual CC, CPRMeter and LifeLine ARM varied and amounted to 40 (38-45) vs. 45 (40-50) vs. 51 (50-52) mm, respectively (p = 0.002). The median chest compression rate was 109 (IQR; 102-131) compressions per minute (CPM) for manual CC, 107 (105-127) CPM for CPRMeter, and 102 (101-102) CPM for LifeLine ARM (p = 0.027). The percentage of correct chest recoil was the highest for LifeLine ARM - 100% (95-100), 80% (60-90) in CPRMeter group, and the lowest for manual CC - 29% (26-48).

CONCLUSIONS

According to the results of this simulation trial, automated chest compression devices (ACCD) should be used for chest compression of patients with suspected/confirmed COVID-19. In the absence of ACCD, it seems reasonable to change the cardiopulmonary resuscitation algorithm (in the context of patients with suspected/confirmed COVID-19) by reducing the duration of the cardiopulmonary resuscitation cycle from the current 2-min to 1-min cycles due to a statistically significant reduction in the quality of chest compressions among rescuers wearing PPE AGP.

Preoperative Vitamin D Concentration and Cardiac, Renal, and Infectious Morbidity after Noncardiac Surgery

BACKGROUND

Low 25-hydroxyvitamin D is associated with cardiovascular, renal, and infectious risks. Postsurgical patients are susceptible to similar complications, but whether vitamin D deficiency contributes to postoperative complications remains unclear. We tested whether low preoperative vitamin D is associated with cardiovascular events within 30 days after noncardiac surgery.

METHODS

We evaluated a subset of patients enrolled in the biobank substudy of the Vascular events In noncardiac Surgery patIents cOhort evaluatioN (VISION) study, who were at least 45 yr with at least an overnight hospitalization. Blood was collected preoperatively, and 25-hydroxyvitamin D was measured in stored samples. The primary outcome was the composite of cardiovascular events (death, myocardial injury, nonfatal cardiac arrest, stroke, congestive heart failure) within 30 postoperative days. Secondary outcomes were kidney injury and infectious complications.

RESULTS

A total of 3,851 participants were eligible for analysis. Preoperative 25-hydroxyvitamin D concentration was 70 ± 30 nmol/l, and 62% of patients were vitamin D deficient. Overall, 26 (0.7%) patients died, 41 (1.1%) had congestive heart failure or nonfatal cardiac arrest, 540 (14%) had myocardial injury, and 15 (0.4%) had strokes. Preoperative vitamin D concentration was not associated with the primary outcome (average relative effect odds ratio [95% CI]: 0.93 [0.85, 1.01] per 10 nmol/l increase in preoperative vitamin D, P = 0.095). However, it was associated with postoperative infection (average relative effect odds ratio [95% CI]: 0.94 [0.90, 0.98] per 10 nmol/l increase in preoperative vitamin D, P adjusted value = 0.005) and kidney function (estimated mean change in postoperative estimated glomerular filtration rate [95% CI]: 0.29 [0.11, 0.48] ml min 1.73 m per 10 nmol/l increase in preoperative vitamin D, P adjusted value = 0.004).

CONCLUSIONS

Preoperative vitamin D was not associated with a composite of postoperative 30-day cardiac outcomes. However, there was a significant association between vitamin D deficiency and a composite of infectious complications and decreased kidney function. While renal effects were not clinically meaningful, the effect of vitamin D supplementation on infectious complications requires further study.