Association of dexmedetomidine use with haemodynamics, postoperative recovery, and cost in paediatric anaesthesia: a hospital registry study

BACKGROUND

Dexmedetomidine utilisation in paediatric patients is increasing. We hypothesised that intraoperative use of dexmedetomidine in children is associated with longer postanaesthesia care unit length of stay, higher healthcare costs, and side-effects.

METHODS

We analysed data from paediatric patients (aged 0-12 yr) between 2016 and 2021 in the Bronx, NY, USA. We matched our cohort with the Healthcare Cost and Utilization Project-Kids' Inpatient Database (HCUP-KID).

RESULTS

Among 18 104 paediatric patients, intraoperative dexmedetomidine utilisation increased from 51.7% to 85.7% between 2016 and 2021 (P<0.001). Dexmedetomidine was dose-dependently associated with a longer postanaesthesia care unit length of stay (adjusted absolute difference [ADadj] 19.7 min; 95% confidence interval [CI]: 18.0-21.4 min; P<0.001, median length of stay of 122 vs 98 min). The association was magnified in children aged ≤2 yr undergoing short (≤60 min) ambulatory procedures (ADadj 33.3 min; 95% CI: 26.3-40.7 min; P<0.001; P-for-interaction <0.001). Dexmedetomidine was associated with higher total hospital costs of USD 1311 (95% CI: USD 835-1800), higher odds of intraoperative mean arterial blood pressure below 55 mm Hg (adjusted odds ratio [ORadj] 1.27; 95% CI: 1.16-1.39; P<0.001), and higher odds of heart rate below 100 beats min-1 (ORadj 1.32; 95% CI: 1.21-1.45; P<0.001), with no preventive effects on emergence delirium requiring postanaesthesia i.v. sedatives (ORadj 1.67; 95% CI: 1.04-2.68; P=0.034).

CONCLUSIONS

Intraoperative use of dexmedetomidine is associated with unwarranted haemodynamic effects, longer postanaesthesia care unit length of stay, and higher costs, without preventive effects on emergence delirium.

Association of ketamine use during procedural sedation with oxygen desaturation and healthcare utilisation: a multicentre retrospective hospital registry study

BACKGROUND

We investigated the effects of ketamine on desaturation and the risk of nursing home discharge in patients undergoing procedural sedation by anaesthetists.

METHODS

We included adult patients who underwent procedures under monitored anaesthetic care between 2005 and 2021 at two academic healthcare networks in the USA. The primary outcome was intraprocedural oxygen desaturation, defined as oxygen saturation <90% for ≥2 consecutive minutes. The co-primary outcome was a nursing home discharge.

RESULTS

Among 234,170 included patients undergoing procedural sedation, intraprocedural desaturation occurred in 5.6% of patients who received ketamine vs 5.2% of patients who did not receive ketamine (adjusted odds ratio [ORadj] 1.22, 95% confidence interval [CI] 1.15-1.29, P<0.001; adjusted absolute risk difference [ARDadj] 1%, 95% CI 0.7-1.3%, P<0.001). The effect was magnified by age >65 yr, smoking, or preprocedural ICU admission (P-for-interaction <0.001, ORadj 1.35, 95% CI 1.25-1.45, P<0.001; ARDadj 2%, 95% CI 1.56-2.49%, P<0.001), procedural risk factors (upper endoscopy of longer than 2 h; P-for-interaction <0.001, ORadj 2.91, 95% CI 1.85-4.58, P<0.001; ARDadj 16.2%, 95% CI 9.8-22.5%, P<0.001), and high ketamine dose (P-for-trend <0.001, ORadj 1.61, 95% CI, 1.43-1.81 for ketamine >0.5 mg kg-1). Concomitant opioid administration mitigated the risk (P-for-interaction <0.001). Ketamine was associated with higher odds of nursing home discharge (ORadj 1.11, 95% CI 1.02-1.21, P=0.012; ARDadj 0.25%, 95% CI 0.05-0.46%, P=0.014).

CONCLUSIONS

Ketamine use for procedural sedation was associated with an increased risk of oxygen desaturation and discharge to a nursing home. The effect was dose-dependent and magnified in subgroups of vulnerable patients.

Association of Obstructive Sleep Apnea With Postoperative Delirium in Procedures of Moderate-to-High Complexity: A Hospital-Registry Study

BACKGROUND

Patients suffering from obstructive sleep apnea (OSA) experience chronic sleep disturbances and desaturation, factors that have been associated with postoperative delirium and that can be aggravated after anesthesia for complex procedures. We investigated whether OSA is associated with delirium after anesthesia, and whether this association is modified by procedural complexity.

METHODS

Hospitalized patients ≥60 years who underwent general anesthesia or procedural sedation for procedures of moderate-to-high complexity between 2009 and 2020 at a tertiary health care network in Massachusetts were included. The primary exposure was OSA, defined based on International Classification of Diseases ( Ninth/Tenth Revision, Clinical Modification ) ( ICD-9 / 10-CM ) diagnostic codes, structured nursing interviews, anesthesia alert notes, and a validated risk score (BOSTN [body mass index, observed apnea, snoring, tiredness, and neck circumference]). The primary end point was delirium within 7 days after the procedure. Multivariable logistic regression and effect modification analyses adjusted for patient demographics, comorbidities, and procedural factors were applied.

RESULTS

A total of 46,352 patients were included, of which 1694 patients (3.7%) developed delirium, 537 (3.2%) with OSA, and 1,157 (4.0%) without OSA. In adjusted analyses, OSA was not associated with postprocedural delirium in the overall cohort (adjusted odds ratio [OR adj ], 1.06; 95% confidence interval [CI], 0.94-1.20; P = .35). However, a high procedural complexity modified the primary association ( P value for interaction = .002). OSA patients had a higher risk of delirium after high-complexity procedures (≥40 work relative value units) such as cardiac (OR adj , 1.33; 95% CI, 1.08-1.64; P = .007, P value for interaction = .005) or thoracic surgery (OR adj , 1.89; 95% CI, 1.19-3.00; P = .007, P value for interaction = .009), but no increased risk after moderate complexity procedures, including general surgery (OR adj , 0.86; 95% CI, 0.55-1.35; P = .52).

CONCLUSIONS

Compared to non-OSA patients, a history of OSA is associated with a higher risk after high-complexity procedures such as cardiac or thoracic surgery but not after procedures of moderate complexity.

Development and validation of an instrument to predict prolonged length of stay in the postanesthesia care unit following ambulatory surgery

PURPOSE

We sought to develop and validate an Anticipated Surveillance Requirement Prediction Instrument (ASRI) for prediction of prolonged postanesthesia care unit length of stay (PACU-LOS, more than four hours) after ambulatory surgery.

METHODS

We analyzed hospital registry data from patients who received anesthesia care in ambulatory surgery centres (ASCs) of university-affiliated hospital networks in New York, USA (development and internal validation cohort [n = 183,711]) and Massachusetts, USA (validation cohort [n = 148,105]). We used stepwise backwards elimination to create ASRI.

RESULTS

The model showed discriminatory ability in the development, internal, and external validation cohorts with areas under the receiver operating characteristic curve of 0.82 (95% confidence interval [CI], 0.82 to 0.83), 0.82 (95% CI, 0.81 to 0.83), and 0.80 (95% CI, 0.79 to 0.80), respectively. In cases started in the afternoon, ASRI scores ≥ 43 had a total predicted risk for PACU stay past 8 p.m. of 32% (95% CI, 31.1 to 33.3) vs 8% (95% CI, 7.9 to 8.5) compared with low score values (P-for-interaction < 0.001), which translated to a higher direct PACU cost of care of USD 207 (95% CI, 194 to 2,019; model estimate, 1.68; 95% CI, 1.64 to 1.73; P < 0.001) The effects of using the ASRI score on PACU use efficiency were greater in a free-standing ASC with no limitations on PACU bed availability.

CONCLUSION

We developed and validated a preoperative prediction tool for prolonged PACU-LOS after ambulatory surgery that can be used to guide scheduling in ambulatory surgery to optimize PACU use during normal work hours, particularly in settings without limitation of PACU bed availability.

Association of reintubation and hospital costs and its modification by postoperative surveillance: A multicenter retrospective cohort study

OBJECTIVE

We estimated hospital costs associated with postoperative reintubation and tested the hypothesis that prolonged surveillance in the post-anesthesia care unit (PACU) modifies the hospital costs of reintubation.

DESIGN

Retrospective observational research study.

SETTING

Two tertiary care academic healthcare networks in the Bronx, New York and Boston, Massachusetts, USA.

PATIENTS

68,125 adult non-cardiac surgical patients undergoing general anesthesia between 2016 and 2021.

INTERVENTIONS

The exposure variable was unplanned reintubation within 7 days of surgery.

MEASUREMENTS

The primary outcome was direct hospital costs associated with patient care related activities. We used a multivariable generalized linear model based on log-transformed costs data, adjusting for pre- and intraoperative confounders. We matched our data with data from the Healthcare Cost and Utilization Project-National Inpatient Sample (HCUP-NIS). In the key secondary analysis, we examined if prolonged postoperative surveillance, defined as PACU utilization (≥4 h) modifies the association between reintubation and costs of care.

MAIN RESULTS

1759 (2.6%) of patients were re-intubated within 7 days after surgery. Reintubation was associated with higher direct hospital costs (adjusted model estimate 2.05; 95% CI: 2.00-2.10) relative to no reintubation. In the HCUP-NIS matched cohort, the adjusted absolute difference (ADadj) in costs amounted to US$ 18,837 (95% CI: 17,921-19,777). The association was modified by the duration of PACU surveillance (p-for-interaction <0.001). In patients with a shorter PACU length of stay, reintubation occurred later (median of 2 days; IQR 1, 5) versus 1 days (IQR 0, 2; p < .001), and was associated with magnified effects on hospital costs compared to patients who stayed in the PACU longer (ADadj of US$ 23,444, 95% CI: 21,217-25,799 versus ADadj of US$ 17,615, 95% CI: 16,350-18,926; p < .001).

CONCLUSION

Postoperative reintubation is associated with 2-fold higher hospital costs. Prolonged surveillance in the recovery room mitigated this effect. The cost-saving effect of longer PACU length of stay was likely driven by earlier reintubation in patients who needed this intervention.

The impact of residency training level on early postoperative desaturation: A retrospective multicenter cohort study

OBJECTIVE

We studied the primary hypothesis that the training level of anesthesiology residents (first clinical anesthesia year, CA1 vs CA2/3 residents) is associated with early postoperative desaturation (oxygen saturation < 90%). We also analyzed the change in the rate (trajectory) of desaturation during the resident's development from CA1 to CA2/3 resident, and its effects on postoperative respiratory complications.

DESIGN

Retrospective hospital registry study.

SETTING

Two university-affiliated hospitals networks (MA and NY, USA).

PATIENTS

140,818 adults undergoing non-cardiac surgery under general anesthesia and extubation in the operating room by residents (n = 378) between 2005 and 2021.

MEASUREMENTS

Multivariate logistic and quantile regression were used in the analyses. The secondary outcome was major respiratory complication within 7 days after surgery.

MAIN RESULTS

In 6.5% and 1.6% of cases, early postoperative desaturation to < 90% and 80% occurred. Compared to CA2/3 residents, CA1 residents had higher odds of experiencing early postoperative desaturation to < 90% and 80% (adjusted odds ratio [ORadj], 1.07; 95%CI 1.03-1.12; p = 0.002, and ORadj 1.10; 95%CI 1.01-1.20; p = 0.037, respectively). The change in postoperative desaturation rate during the transition from CA1 to CA2/3 status varied substantially from ORadj 0.80 (decreased risk) to 1.33 (increased risk). Major respiratory complication did not differ between experience levels (p = 0.52). However, a strong decline in improvement regarding the rate of postoperative desaturation during the transition from CA1 to CA2/3, was paralleled by an increased odds of major respiratory complication for CA2/3 residents (ORadj 1.20; 95%CI 1.02-1.42; p = 0.026, p-for-interaction = 0.056).

CONCLUSION

Patients treated by CA1 residents have an increased risk of postoperative desaturation. Some residents show an improvement and others a decline in postoperative desaturation rate. Our secondary analysis suggests that there should be more focus on those residents who had a declining performance in postoperative desaturation despite becoming more experienced.

Loss of Independent Living in Patients Undergoing Transcatheter or Surgical Aortic Valve Replacement: A Retrospective Cohort Study

BACKGROUND

The recommendation for transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) in patients 65 to 80 years of age is equivocal, leaving patients with a difficult decision. We evaluated whether TAVR compared to SAVR is associated with reduced odds for loss of independent living in patients ≤65, 66 to 79, and ≥80 years of age. Further, we explored mechanisms of the association of TAVR and adverse discharge.

METHODS

Adult patients undergoing TAVR or SAVR within a large academic medical system who lived independently before the procedure were included. A multivariable logistic regression model, adjusting for a priori defined confounders including patient demographics, preoperative comorbidities, and a risk score for adverse discharge after cardiac surgery, was used to assess the primary association. We tested the interaction of patient age with the association between aortic valve replacement (AVR) procedure and loss of independent living. We further assessed whether the primary association was mediated (ie, percentage of the association that can be attributed to the mediator) by the procedural duration as prespecified mediator.

RESULTS

A total of 1751 patients (age median [quartiles; min-max], 76 [67, 84; 23-100]; sex, 56% female) were included. A total of 27% (222/812) of these patients undergoing SAVR and 20% (188/939) undergoing TAVR lost the ability to live independently. In our cohort, TAVR was associated with reduced odds for loss of independent living compared to SAVR (adjusted odds ratio [OR adj ] 0.19 [95% confidence interval {CI}, 0.14-0.26]; P < .001). This association was attenuated in patients ≤65 years of age (OR adj 0.63 [0.26-1.56]; P = .32) and between 66 and 79 years of age (OR adj 0.23 [0.15-0.35]; P < .001), and magnified in patients ≥80 years of age (OR adj 0.16 [0.10-0.25]; P < .001; P -for-interaction = .004). Among those >65 years of age, a shorter procedural duration mediated 50% (95% CI, 28-76; P < .001) of the beneficial association of TAVR and independent living.

CONCLUSIONS

Patients >65 years of age undergoing TAVR compared to SAVR had reduced odds for loss of independent living. This association was partly mediated by shorter procedural duration. No association between AVR approach and the primary end point was found in patients ≤65 years of age.

Association Between Intraoperative Dexamethasone and Postoperative Mortality in Patients Undergoing Oncologic Surgery: A Multicentric Cohort Study

OBJECTIVE

We examined the effects of dexamethasone on postoperative mortality, recurrence-free survival, and side effects in patients undergoing oncologic operations.

BACKGROUND

Dexamethasone prevents nausea and vomiting after anesthesia and may affect cancer proliferation.

METHODS

A total of 30,561 adult patients undergoing solid cancer resection between 2005 and 2020 were included. Multivariable logistic regression was applied to investigate the effect of dexamethasone on 1-year mortality and recurrence-free survival. Effect modification by the cancer's potential for immunogenicity, defined as a recommendation for checkpoint inhibitor therapy based on the National Comprehensive Cancer Network guidelines, was investigated through interaction term analysis. Key safety endpoints were dexamethasone-associated risk of hyperglycemia >180 mg/dL within 24 hours and surgical site infections within 30 days after surgery.

RESULTS

Dexamethasone was administered to 38.2% (11,666/30,561) of patients (6.5±2.3 mg). Overall, 3.2% (n=980/30,561) died and 15.4% (n=4718/30,561) experienced cancer recurrence within 1 year of the operation. Dexamethasone was associated with a -0.6% (95% confidence interval: -1.1, -0.2, P =0.007) 1-year mortality risk reduction [adjusted odds ratio (OR adj ): 0.79 (0.67, 0.94), P =0.009; hazard ratio=0.82 (0.69, 0.96), P =0.016] and higher odds of recurrence-free survival [OR adj : 1.28 (1.18, 1.39), P <0.001]. This effect was only present in patients with solid cancers who were defined as not to respond to checkpoint inhibitor therapy [OR adj : 0.70 (0.57, 0.87), P =0.001 vs OR adj : 1.13 (0.85, 1.50), P =0.40]. A high (>0.09 mg/kg) dose of dexamethasone increased the risk of postoperative hyperglycemia [OR adj : 1.55 (1.32, 1.82), P <0.001], but not for surgical site infections [OR adj : 0.84 (0.42, 1.71), P =0.63].

CONCLUSIONS

Dexamethasone is associated with decreased 1-year mortality and cancer recurrence in patients undergoing surgical resection of cancers that are not candidates for immune modulators. Dexamethasone increased the risk of postoperative hyperglycemia, however, no increase in surgical site infections was identified.

Consensus guidelines for the perioperative management of patients undergoing endoscopic retrograde cholangiopancreatography

Deep sedation without tracheal intubation (monitored anaesthesia care) and general anaesthesia with tracheal intubation are commonly used anaesthesia techniques for endoscopic retrograde cholangiopancreatography (ERCP). There are distinct pathophysiological differences between monitored anaesthesia care and general anaesthesia that need to be considered depending on the nature and severity of the patient's underlying disease, comorbidities, and procedural risks. An international group of expert anaesthesiologists and gastroenterologists created clinically relevant questions regarding the merits and risks of monitored anaesthesia care vs general anaesthesia in specific clinical scenarios for planning optimal anaesthetic approaches for ERCP. Using a modified Delphi approach, the group created practical recommendations for anaesthesiologists, with the aim of reducing the incidence of perioperative adverse outcomes while maximising healthcare resource utilisation. In the majority of clinical scenarios analysed, our expert recommendations favour monitored anaesthesia care over general anaesthesia. Patients with increased risk of pulmonary aspiration and those undergoing prolonged procedures of high complexity were thought to benefit from general anaesthesia with tracheal intubation. Patient age and ASA physical status were not considered to be factors for choosing between monitored anaesthesia care and general anaesthesia. Monitored anaesthesia care is the favoured anaesthesia plan for ERCP. An individual risk-benefit analysis that takes into account provider and institutional experience, patient comorbidities, and procedural risks is also needed.

The effects of sugammadex vs. neostigmine on postoperative respiratory complications and advanced healthcare utilisation: a multicentre retrospective cohort study

Reversing neuromuscular blockade with sugammadex can eliminate residual paralysis, which has been associated with postoperative respiratory complications. There are equivocal data on whether sugammadex reduces these when compared with neostigmine. We investigated the association of the choice of reversal drug with postoperative respiratory complications and advanced healthcare utilisation. We included adult patients who underwent surgery and received general anaesthesia with sugammadex or neostigmine reversal at two academic healthcare networks between January 2016 and June 2021. The primary outcome was postoperative respiratory complications, defined as post-extubation oxygen saturation < 90%, respiratory failure requiring non-invasive ventilation, or tracheal re-intubation within 7 days. Our main secondary outcome was advanced healthcare utilisation, a composite outcome including: 7-day unplanned intensive care unit admission; 30-day hospital readmission; or non-home discharge. In total, 5746 (6.9%) of 83,250 included patients experienced postoperative respiratory complications. This was not associated with the reversal drug (adjusted OR (95%CI) 1.01 (0.94-1.08); p = 0.76). After excluding patients admitted from skilled nursing facilities, 8372 (10.5%) patients required advanced healthcare utilisation, which was not associated with the choice of reversal (adjusted OR (95%CI) 0.95 (0.89-1.01); p = 0.11). Equivalence testing supported an equivalent effect size of sugammadex and neostigmine on both outcomes, and neostigmine was non-inferior to sugammadex with regard to postoperative respiratory complications or advanced healthcare utilisation. Finally, there was no association between the reversal drug and major adverse cardiovascular events (adjusted OR 1.07 (0.94-1.21); p = 0.32). Compared with neostigmine, reversal of neuromuscular blockade with sugammadex was not associated with a reduction in postoperative respiratory complications or post-procedural advanced healthcare utilisation.

Association of sugammadex reversal of neuromuscular block and postoperative length of stay in the ambulatory care facility: a multicentre hospital registry study

BACKGROUND

Encapsulation of rocuronium or vecuronium with sugammadex can reverse neuromuscular block faster than neostigmine reversal. This pharmacodynamic profile might facilitate patient discharge after ambulatory surgery.

METHODS

We included patients who underwent ambulatory surgery with general anaesthesia and neuromuscular block between 2016 and 2021 from hospital registries at two large academic healthcare networks in the USA. The primary outcome was postoperative length of stay in the ambulatory care facility (PLOS-ACF). We examined post hoc whether the type of reversal affects postoperative nausea and vomiting and direct hospital costs.

RESULTS

Among the 29 316 patients included, 8945 (30.5%) received sugammadex and 20 371 (69.5%) received neostigmine for reversal. PLOS-ACF and costs were lower in patients who received sugammadex vs neostigmine (adjusted difference in PLOS-ACF: -9.5 min; 95% confidence interval [95% CI], -10.5 to -8.5 min; adjusted difference in direct hospital costs: -US$77; 95% CI, -$88 to -$66; respectively; P<0.001). The association was magnified in patients over age 65 yr, with ASA physical status >2 undergoing short procedures (<2 h) (adjusted difference in PLOS-ACF: -18.2 min; 95% CI, -23.8 to -12.4 min; adjusted difference in direct hospital costs: -$176; 95% CI, -$220 to -$128; P<0.001). Sugammadex use was associated with reduced postoperative nausea and vomiting (17.2% vs 19.6%, P<0.001), which mediated its effects on length of stay.

CONCLUSIONS

Reversal with sugammadex compared with neostigmine was associated with a small decrease in postoperative length of stay in the ambulatory care unit. The effect was magnified in older and high-risk patients, and can be explained by reduced postoperative nausea and vomiting. Sugammadex reversal in ambulatory surgery may also help reduce cost of care.

Comparison of the effects of sugammadex versus neostigmine for reversal of neuromuscular block on hospital costs of care

BACKGROUND

Sugammadex reversal of neuromuscular block facilitates recovery of neuromuscular function after surgery, but the drug is expensive. We evaluated the effects of sugammadex on hospital costs of care.

METHODS

We analysed 79 474 adult surgical patients who received neuromuscular blocking agents and reversal from two academic healthcare networks between 2016 and 2021 to calculate differences in direct costs. We matched our data with data from the Healthcare Cost and Utilization Project-National Inpatient Sample (HCUP-NIS) to calculate differences in total costs in US dollars. Perioperative risk profiles were defined based on ASA physical status and admission status (ambulatory surgery vs hospitalisation).

RESULTS

Based on our registry data analysis, administration of sugammadex vs neostigmine was associated with lower direct costs (-1.3% lower costs; 95% confidence interval [CI], -0.5 to -2.2%; P=0.002). In the HCUP-NIS matched cohort, sugammadex use was associated with US$232 lower total costs (95% CI, -US$376 to -US$88; P=0.002). Subgroup analysis revealed that sugammadex was associated with US$1042 lower total costs (95% CI, -US$1198 to -US$884; P<0.001) in patients with lower risk. In contrast, sugammadex was associated with US$620 higher total costs (95% CI, US$377 to US$865; P<0.001) in patients with a higher risk (American Society of Anesthesiologists physical status ≥3 and preoperative hospitalisation).

CONCLUSIONS

The effects of using sugammadex on costs of care depend on patient risk, defined based on comorbidities and admission status. We observed lower costs of care in patients with lower risk and higher costs of care in hospitalised surgical patients with severe comorbidities.

Subjective Assessment of Motor Function by the Bedside Nurses in Mechanically Ventilated Surgical Intensive Care Unit Patients Predicts Tracheostomy

OBJECTIVE

In many institutions, intensive care unit (ICU) nurses assess their patients' muscle function as part of their routine bedside examination. We tested the research hypothesis that this subjective examination of muscle function prior to extubation predicts tracheostomy requirement.

METHODS

Adult, mechanically ventilated patients admitted to 7 ICUs at Beth Israel Deaconess Medical Center (BIDMC) between 2008 and 2019 were included in this observational study. Assessment of motor function was performed every four hours by ICU nurses. Multivariable logistic regression analysis controlled for acute disease severity, delirium risk assessment through the confusion assessment method for the ICU (CAM-ICU), and pre-defined predictors of extubation failure was applied to examine the association of motor function and tracheostomy within 30 days after extubation.

RESULTS

Within 30 days after extubation, 891 of 9609 (9.3%) included patients required a tracheostomy. The inability to spontaneously move and hold extremities against gravity within 24 h prior to extubation was associated with significantly higher odds of 30-day tracheostomy (adjusted OR 1.56, 95% CI 1.27-1.91, p < 0.001, adjusted absolute risk difference (aARD) 2.8% (p < 0.001)). The effect was magnified among patients who were mechanically ventilated for >7 days (aARD 21.8%, 95% CI 12.4-31.2%, p-for-interaction = 0.015).

CONCLUSIONS

ICU nurses' subjective assessment of motor function is associated with 30-day tracheostomy risk, independent of known risk factors. Muscle function measurements by nursing staff in the ICU should be discussed during interprofessional rounds.

Incidence and predictors of case cancellation within 24 h in patients scheduled for elective surgical procedures

OBJECTIVE

Avoidable case cancellations within 24 h reduce operating room (OR) efficiency, add unnecessary costs, and may have physical and emotional consequences for patients and their families. We developed and validated a prediction tool that can be used to guide same day case cancellation reduction initiatives.

DESIGN

Retrospective hospital registry study.

SETTING

University-affiliated hospitals network (NY, USA).

PATIENTS

246,612 (1/2016-6/2021) and 58,662 (7/2021-6/2022) scheduled elective procedures were included in the development and validation cohort.

MEASUREMENTS

Case cancellation within 24 h was defined as cancelling a surgical procedure within 24 h of the scheduled date and time. Our candidate predictors were defined a priori and included patient-, procedural-, and appointment-related factors. We created a prediction tool using backward stepwise logistic regression to predict case cancellation within 24 h. The model was subsequently recalibrated and validated in a cohort of patients who were recently scheduled for surgery.

MAIN RESULTS

8.6% and 8.7% scheduled procedures were cancelled within 24 h of the intended procedure in the development and validation cohort, respectively. The final weighted score contains 29 predictors. A cutoff value of 15 score points predicted a 10.3% case cancellation rate with a negative predictive value of 0.96, and a positive predictive value of 0.21. The prediction model showed good discrimination in the development and validation cohort with an area under the receiver operating characteristic curve (AUC) of 0.79 (95% confidence interval 0.79-0. 80) and an AUC of 0.73 (95% confidence interval 0.72-0.73), respectively.

CONCLUSIONS

We present a validated preoperative prediction tool for case cancellation within 24 h of surgery. We utilize the instrument in our institution to identify patients with high risk of case cancellation. We describe a process for recalibration such that other institutions can also use the score to guide same day case cancellation reduction initiatives.

Association Between Intraoperative Arterial Hypotension and Postoperative Delirium After Noncardiac Surgery: A Retrospective Multicenter Cohort Study

BACKGROUND

It is unclear whether intraoperative arterial hypotension is associated with postoperative delirium. We hypothesized that intraoperative hypotension within a range frequently observed in clinical practice is associated with increased odds of delirium after surgery.

METHODS

Adult noncardiac surgical patients undergoing general anesthesia at 2 academic medical centers between 2005 and 2017 were included in this retrospective cohort study. The primary exposure was intraoperative hypotension, defined as the cumulative duration of an intraoperative mean arterial pressure (MAP) <55 mm Hg, categorized into and short (<15 minutes; median [interquartile range {IQR}], 2 [1-4] minutes) and prolonged (≥15 minutes; median [IQR], 21 [17-31] minutes) durations of intraoperative hypotension. The primary outcome was a new diagnosis of delirium within 30 days after surgery. In secondary analyses, we assessed the association between a MAP decrease of >30% from baseline and postoperative delirium. Multivariable logistic regression adjusted for patient- and procedure-related factors, including demographics, comorbidities, and markers of procedural severity, was used.

RESULTS

Among 316,717 included surgical patients, 2183 (0.7%) were diagnosed with delirium within 30 days after surgery; 41.7% and 2.6% of patients had a MAP <55 mm Hg for a short and a prolonged duration, respectively. A MAP <55 mm Hg was associated with postoperative delirium compared to no hypotension (short duration of MAP <55 mm Hg: adjusted odds ratio [ORadj], 1.22; 95% confidence interval [CI], 1.11-1.33; P < .001 and prolonged duration of MAP <55 mm Hg: ORadj, 1.57; 95% CI, 1.27-1.94; P < .001). Compared to a short duration of a MAP <55 mm Hg, a prolonged duration of a MAP <55 mm Hg was associated with greater odds of postoperative delirium (ORadj, 1.29; 95% CI, 1.05-1.58; P = .016). The association between intraoperative hypotension and postoperative delirium was duration-dependent (ORadj for every 10 cumulative minutes of MAP <55 mm Hg: 1.06; 95% CI, 1.02-1.09; P =.001) and magnified in patients who underwent surgeries of longer duration (P for interaction = .046; MAP <55 mm Hg versus no MAP <55 mm Hg in patients undergoing surgery of >3 hours: ORadj, 1.40; 95% CI, 1.23-1.61; P < .001). A MAP decrease of >30% from baseline was not associated with postoperative delirium compared to no hypotension, also when additionally adjusted for the cumulative duration of a MAP <55 mm Hg (short duration of MAP decrease >30%: ORadj, 1.13; 95% CI, 0.91-1.40; P = .262 and prolonged duration of MAP decrease >30%: ORadj, 1.19; 95% CI, 0.95-1.49; P = .141).

CONCLUSIONS

In patients undergoing noncardiac surgery, a MAP <55 mm Hg was associated with a duration-dependent increase in odds of postoperative delirium. This association was magnified in patients who underwent surgery of long duration.

Effect of Intraoperative Arterial Hypotension on the Risk of Perioperative Stroke After Noncardiac Surgery: A Retrospective Multicenter Cohort Study

BACKGROUND

Intraoperative cerebral blood flow is mainly determined by cerebral perfusion pressure and cerebral autoregulation of vasomotor tone. About 1% of patients undergoing noncardiac surgery develop ischemic stroke. We hypothesized that intraoperative hypotension within a range frequently observed in clinical practice is associated with an increased risk of perioperative ischemic stroke within 7 days after surgery.

METHODS

Adult noncardiac surgical patients undergoing general anesthesia at Beth Israel Deaconess Medical Center and Massachusetts General Hospital between 2005 and 2017 were included in this retrospective cohort study. The primary exposure was intraoperative hypotension, defined as a decrease in mean arterial pressure (MAP) below 55 mm Hg, categorized into no intraoperative hypotension, short (<15 minutes, median [interquartile range {IQR}], 2 minutes [1-5 minutes]) and prolonged (≥15 minutes, median [IQR], 21 minutes [17-31 minutes]) durations. The primary outcome was a new diagnosis of early perioperative ischemic stroke within 7 days after surgery. In secondary analyses, we assessed the effect of a MAP decrease by >30% from baseline on perioperative stroke. Analyses were adjusted for the preoperative STRoke After Surgery (STRAS) prediction score, work relative value units, and duration of surgery.

RESULTS

Among 358,391 included patients, a total of 1553 (0.4%) experienced an early perioperative ischemic stroke. About 42% and 3% of patients had a MAP of below 55 mm Hg for a short and a prolonged duration, and 49% and 29% had a MAP decrease by >30% from baseline for a short and a prolonged duration, respectively. In an adjusted analysis, neither a MAP <55 mm Hg (short duration: adjusted odds ratio [ORadj], 0.95; 95% confidence interval [CI], 0.85-1.07; P = .417 and prolonged duration: ORadj, 1.18; 95% CI, 0.91-1.55; P = .220) nor a MAP decrease >30% (short duration: ORadj, 0.97; 95% CI, 0.67-1.42; P = .883 and prolonged duration: ORadj, 1.30; 95% CI, 0.89-1.90; P = .176) was associated with early perioperative stroke. A high a priori stroke risk quantified based on preoperatively available risk factors (STRAS prediction score) was associated with longer intraoperative hypotension (adjusted incidence rate ratio, 1.04; 95% CI, 1.04-1.05; P < .001 per 5 points of the STRAS prediction score).

CONCLUSIONS

This study found no evidence to conclude that intraoperative hypotension within the range studied was associated with early perioperative stroke within 7 days after surgery. These findings emphasize the importance of perioperative cerebral blood flow autoregulation to prevent ischemic stroke.

Association between preoperative administration of gabapentinoids and 30-day hospital readmission: A retrospective hospital registry study

STUDY OBJECTIVE

To evaluate the effectiveness of preoperative gabapentinoid administration.

DESIGN

Retrospective hospital registry study.

SETTING

Tertiary referral center (Boston, MA).

PATIENTS

111,008 adult non-emergency, non-cardiac surgical patients between 2014 and 2018.

INTERVENTIONS

Preoperative administration of gabapentinoids (gabapentin or pregabalin).

MEASUREMENTS

We tested the primary hypothesis that preoperative gabapentinoid use was associated with lower odds of hospital readmission within 30 days. Contingent on this hypothesis, we examined whether lower intraoperative opioid utilization mediated this effect. Secondary outcome was postoperative respiratory complications.

MAIN RESULTS

Gabapentinoid administration was associated with lower odds of readmission (adjusted odds ratio [OR_adj] 0.80 [95% CI, 0.75-0.85]; p < 0.001). This effect was in part mediated by lower intraoperative opioid utilization in patients receiving gabapentinoids (8.2% [2.4-11.5%]; p = 0.012). Readmissions for gastrointestinal disorders (OR_adj 0.74 [0.60-0.90]; p = 0.003), neuro-psychiatric complications (OR_adj 0.66 [0.49-0.87]; p = 0.004), non-surgical site infections (OR_adj 0.68 [0.52-0.88; p = 0.004) and trauma or poisoning (OR_adj 0.25 [0.16-0.41]; p < 0.001) occurred less frequently in patients receiving gabapentinoids. The risk of postoperative respiratory complications was lower in patients receiving gabapentinoids (OR_adj 0.77 [0.70-0.85]; p < 0.001). Lower doses of pregabalin (< 75 mg) and gabapentin (< 300 mg) compared to both, no and high-dose administration of gabapentinoids, were associated with a lower risk of postoperative respiratory complications (OR_adj 0.61 [0.50-0.75]; p < 0.001 and OR_adj 0.70 [0.53-0.92]; p = 0.012, respectively). These lower gabapentinoid doses prevented 30-day readmission (OR_adj 0.74 [0.65-0.85]; p < 0.001). The results were robust in several sensitivity analyses including surgical procedure defined subgroups and patients undergoing ambulatory surgery.

CONCLUSIONS

The preoperative use of pregabalin and gabapentin, up to doses of 75 and 300 mg respectively, mitigates the risks of hospital readmission and postoperative respiratory complications which can in part be explained by lower intraoperative opioid use. Further research is warranted to elucidate mechanisms of the preventive action.

Study protocol for a randomised controlled trial evaluating the effects of the orexin receptor antagonist suvorexant on sleep architecture and delirium in the intensive care unit

INTRODUCTION

Insomnia frequently occurs in patients admitted to an intensive care unit (ICU). Sleep-promoting agents may reduce rapid eye movement sleep and have deliriogenic effects. Suvorexant (Belsomra) is an orexin receptor antagonist with Food and Drug Administration (FDA) approval for the treatment of adult insomnia, which improves sleep onset and maintenance as well as subjective measures of quality of sleep. This trial will evaluate the efficacy of postoperative oral suvorexant treatment on night-time wakefulness after persistent sleep onset as well as the incidence and duration of delirium among adult cardiac surgical patients.

METHODS AND ANALYSIS

In this single-centre, randomised, double-blind, placebo-controlled trial, we will enrol 120 patients, aged 60 years or older, undergoing elective cardiac surgery with planned postoperative admission to the ICU. Participants will be randomised to receive oral suvorexant (20 mg) or placebo one time a day starting the night after extubation. The primary outcome will be wakefulness after persistent sleep onset. The secondary outcome will be total sleep time. Exploratory outcomes will include time to sleep onset, incidence of postoperative in-hospital delirium, number of delirium-free days and subjective sleep quality.

ETHICS AND DISSEMINATION

Ethics approval was obtained through the 'Committee on Clinical Investigations' at Beth Israel Deaconess Medical Center (protocol number 2019P000759). The findings will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

This trial has been registered at clinicaltrials.gov on 17 September 2019 (NCT04092894).

Effects of repeated exposure to different concentrations of sevoflurane on the neonatal mouse hippocampus

Background and objectives

Developing brain is more vulnerable to environmental risk than is the developed brain. We evaluated the effects of repeated exposure to different concentrations of sevoflurane on the neonatal mouse hippocampus using stereological methods.

Methods

Eighteen neonatal male mice were randomly divided into three groups. Group A, inhaled sevoflurane at a concentration of 1.5%; Group B, inhaled sevoflurane at a concentration of 3%; and Group C (control group), inhaled only 100% oxygen. Treatments were applied for 30 min a day for 7 consecutive days. The hippocampal volume, dendrite length, number of neurons, and number of glial cells were evaluated in each group using stereological estimations.

Results

We identified a ∼2% reduction in the volume of the hippocampus in Group A compared to Group C. Mean hippocampal volume was ∼11% smaller in Group B than it was in Group C. However, these differences in hippocampal volume between the groups were not statistically significant (p > 0.05 for all). As for the number of neurons, we found significantly fewer neurons in Group A (∼29% less) and Group B (∼43% less) than we did in Group C (p < 0.05 for both). The dendrite length was ∼8% shorter in Group A and ∼11% shorter in Group B than it was in Group C.

Conclusions

Repeated exposure to sevoflurane, regardless of the concentration, reduced the volume of the neonatal mouse hippocampus, as well as the number of neurons and dendrite length.

[Effects of repeated exposure to different concentrations of sevoflurane on the neonatal mouse hippocampus]

BACKGROUND AND OBJECTIVES

Developing brain is more vulnerable to environmental risk than is the developed brain. We evaluated the effects of repeated exposure to different concentrations of sevoflurane on the neonatal mouse hippocampus using stereological methods.

METHODS

Eighteen neonatal male mice were randomly divided into three groups. Group A, inhaled sevoflurane at a concentration of 1.5%; Group B, inhaled sevoflurane at a concentration of 3%; and Group C (control group), inhaled only 100% oxygen. Treatments were applied for 30min a day for 7 consecutive days. The hippocampal volume, dendrite length, number of neurons, and number of glial cells were evaluated in each group using stereological estimations.

RESULTS

We identified a ∼2% reduction in the volume of the hippocampus in Group A compared to Group C. Mean hippocampal volume was ∼11% smaller in Group B than it was in Group C. However, these differences in hippocampal volume between the groups were not statistically significant (p>0.05 for all). As for the number of neurons, we found significantly fewer neurons in Group A (∼29% less) and Group B (∼43% less) than we did in Group C (p<0.05 for both). The dendrite length was ∼8% shorter in Group A and ∼11% shorter in Group B than it was in Group C.

CONCLUSIONS

Repeated exposure to sevoflurane, regardless of the concentration, reduced the volume of the neonatal mouse hippocampus, as well as the number of neurons and dendrite length.

[Comparison of granisetron and lidocaine on reducing injection pain of etomidate: a controlled randomized study]

BACKGROUND AND OBJECTIVES

Reducing pain on injection of anesthetic drugs is of importance to every anesthesiologist. In this study we pursued to define if pretreatment by granisetron reduces the pain on injection of etomidate similar to lidocaine.

METHODS

Thirty patients aged between 18 and 50 years of American Society of Anesthesiologists physical status class I or II, whom were candidates for elective laparoscopic cholecystectomy surgery were enrolled in this study. Two 20 gauge cannulas were inserted into the veins on the dorsum of both hands and 100mL of normal saline was administered during a 10min period from each cannula. Using an elastic band as a tourniquet, venous drainage of both hands was occluded. 2mL of granisetron was administered into one hand and 2mL of lidocaine 2% at the same time into the other hand. One minute later the elastic band was opened and 2mL of etomidate was administered to each hand with equal rates. The patients were asked to give a score from 0 to 10 (0=no pain, 10=severe pain) to each the pain sensed in each hand.

RESULTS

Two patients were deeply sedated after injection of etomidate and unable to answer any questions. The mean numerical rating score for injection pain of intravenously administered etomidate after intravenous granisetron was 2.3±1.7, which was lower when compared with pain sensed due to intravenously administered etomidate after administration of lidocaine 2% (4.6±1.8), p<0.05.

CONCLUSION

The result of this study demonstrated that, granisetron reduces pain on injection of etomidate more efficiently than lidocaine.

[Evaluation of spinal anesthesia blockade time with 0.5% hyperbaric bupivacaine, with or without sufentanil, in chronic opioid users: a randomized clinical trial]

OBJECTIVE

The primary outcome of this study was to evaluate the effect of adding sufentanil to hyperbaric bupivacaine on duration of sensory blockade of spinal anesthesia in chronic opioid users in comparison with non-addicts.

METHODS

Sixty patients scheduled for orthopedic surgery under spinal anesthesia were allocated into four groups: group 1 (no history of opium use who received intrathecal hyperbaric bupivacaine along with 1mL saline as placebo); group 2 (no history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]); group 3 (positive history of opium use who received intrathecal bupivacaine along with 1mL saline as placebo) and group 4 (positive history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]). The onset time and duration of sensory and motor blockade were measured.

RESULTS

The duration of sensory blockade in group 3 was 120±23.1min which was significantly less than other groups (G1=148±28.7, G2=144±26.4, G4=139±24.7, p=0.007). The duration of motor blockade in group 3 was 145±30.0min which was significantly less than other groups (G1=164±36.0, G2=174±26.8, G4=174±24.9, p=0.03).

CONCLUSIONS

Addition of 5μg intrathecal sufentanil to hyperbaric bupivacaine in chronic opioid users lengthened the sensory and motor duration of blockade to be equivalent to blockade measured in non-addicts.

Adding Sufentanil to TAP Block Hyperbaric Bupivacaine Decreases Post-Cesarean Delivery Morphine Consumption

Pain management is crucially important in the postoperative period as it increases patient comfort and satisfaction. The primary outcome of present study was to evaluate the effect of sufentanil added to hyperbaric bupivacaine solution 0.25% in transversus abdominis plane (TAP) block, on postoperative analgesic consumption. Fifty ASA physical status I-II term primiparous single-tone pregnant women aged 20-40 years scheduled for elective cesarean delivery with Pfannenstiel incision under general anaesthesia were enrolled in this randomized, double-blind, placebo-controlled trial. Ultrasound guided TAP block was performed at the end of surgery. Patients were randomly enrolled into two groups. Patients in the study group received 20 ml of hyperbaric bupivacaine 0.25% plus 1mL of sufentanil on either side while patients in the placebo group were administered 20 ml of hyperbaric bupivacaine 0.25% along with 1mL of placebo. Post-cesarean delivery visual analogue scale (VAS) for pain and morphine usage were measured and recorded. The morphine consumption was significantly less in the study group (37.2 ± 16.1 mg) than the control group (52.8 ± 16.7 mg, P =0.002).The VAS for pain both in rest and coughing were same in groups. Sufentanil added to 0.25% hyperbaric bupivacaine in TAP block decreases post cesarean delivery morphine consumption.

Evaluation of spinal anesthesia blockade time with 0.5% hyperbaric bupivacaine, with or without sufentanil, in chronic opioid users: a randomized clinical trial

OBJECTIVE

The primary outcome of this study was to evaluate the effect of adding sufentanil to hyperbaric bupivacaine on duration of sensory blockade of spinal anesthesia in chronic opioid users in comparison with non-addicts.

METHODS

Sixty patients scheduled for orthopedic surgery under spinal anesthesia were allocated into four groups: group 1 (no history of opium use who received intrathecal hyperbaric bupivacaine along with 1mL saline as placebo); group 2 (no history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]); group 3 (positive history of opium use who received intrathecal bupivacaine along with 1mL saline as placebo) and group 4 (positive history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]). The onset time and duration of sensory and motor blockade were measured.

RESULTS

The duration of sensory blockade in group 3 was 120±23.1min which was significantly less than other groups (G1=148±28.7, G2=144±26.4, G4=139±24.7, p=0.007). The duration of motor blockade in group 3 was 145±30.0min which was significantly less than other groups (G1=164±36.0, G2=174±26.8, G4=174±24.9, p=0.03).

CONCLUSIONS

Addition of 5μg intrathecal sufentanil to hyperbaric bupivacaine in chronic opioid users lengthened the sensory and motor duration of blockade to be equivalent to blockade measured in non-addicts.

Efficacy of transverse abdominis plane block in reduction of postoperation pain in laparoscopic cholecystectomy

OBJECTIVE

Transversus abdominis plane (TAP) block is a recently introduced regional anesthesia technique that is used for postoperative pain reduction in some abdominal surgeries. The present study evaluated the efficacy of the TAP block on the post laparoscopic cholecystectomy pain intensity and analgesic consumption.

METHODS

Fifty-four patients were enrolled in three groups: TAP block with normal saline (Group 1, n = 18); TAP block with bupivacaine (Group 2, n = 18); and TAP block with bupivacaine plus sufentanil (Group 3, n = 18). The time to the first fentanyl request, fentanyl consumption in the 24 hours following surgery, and postoperative pain intensity at 30 minutes, 1 hour, 6 hours, 12 hours, and 24 hours following discharge for recovery were measured and recorded.

RESULTS

The total amount of 24-hour fentanyl consumption was higher in Group 1 (877.8 ± 338.8 μg) than either Group 2 (566.7 ± 367.8 μg) or Group 3 (555.5 ± 356.8 μg; p = 0.03). Postoperative pain score was higher in Group 1 than intervention groups (p = 0.006); however, there was no significant difference in intervention groups. The time to the first fentanyl request in Group 1 (79.44 ± 42.2) was significantly lower than Group 3 (206.38 ± 112.7; p = 0.001).

CONCLUSION

The present study demonstrated that bilateral TAP block with 0.5% bupivacaine reduces post laparoscopic cholecystectomy pain intensity and fentanyl request and prolongs time to the first analgesic request. Adding sufentanil to the block solution reduced neither pain intensity nor fentanyl further consumption.

Naloxone added to bupivacaine or bupivacaine-fentanyl prolongs motor and sensory block during supraclavicular brachial plexus blockade: a randomized clinical trial

BACKGROUND

In this study, the effect of naloxone on duration of supraclavicular brachial plexus block was evaluated. It was hypothesized that naloxone can increase the duration of neural blockade.

METHODS

Sixty-eight patients scheduled for surgery under supraclavicular brachial plexus block were randomly assigned to receive 30 ml bupivacaine (Group C); 30 ml bupivacaine with 100 μg of fentanyl (Group F); 30 ml bupivacaine with 100 ng naloxone (Group N); or 30 ml bupivacaine with 100 μg of fentanyl and 100 ng naloxone (Group N + F). Sensory and motor blockade were recorded at 5, 15, and 30 min following the block, and every 10 min following the end of surgery. Duration of sensory and motor block was considered to be the time interval between the complete block and the first postoperative pain and complete recovery of motor functions.

RESULTS

Sensory and motor onset times were the same in all groups. The duration of sensory and motor block in Group C (11.3 ± 1.7 h and 4.56 ± 1.0 h) and Group F (12.8 ± 3.3 h and 5.1 ± 2.0 h) were less than in the other groups (18.1 ± 2.2 h and 6.18 ± 1.0 h in Group N, and 15.8 ± 2.9 h and 6.53 ± 1.1 h in Group N + F, P < 0.0001).

CONCLUSION

Addition of naloxone to bupivacaine in supraclavicular brachial plexus block prolonged the duration of the neural blockade.

The Effect of Adding Sufentanil to 0.5% Hyperbaric Bupivacaine on Duration of Brachial Plexus Blockade in Chronic Opium Abusers: a Randomized Clinical Trial

Background:

Anesthesia induction in patients with current substance abuse can be a challenge for anesthesiologists.

Objectives:

This study aimed to evaluate the effect of adding Sufentanil to Bupivacaine on duration of brachial plexus nerve block.

Patients and Methods:

One hundred and twenty patients with (Groups C and D) and without (Groups A and B) a history of opium abuse (60 in each group) scheduled for elective upper extremity procedures were randomly assigned to either receive 30 mL bupivacaine alone (Groups A and C) or in combination with additional 10 µg sufentanil (Groups B and D). An ultrasound-guided technique was applied to perform upper extremity brachial plexus blockade. The onset and duration of sensory and motor blocks were recorded and compared between the four groups.

Results:

The duration of sensory and motor block were significantly less in Group C (537.0 ± 40.1 minutes, 479.0 ± 34.8 minutes) and the longest duration of sensory and motor block was observed in group B (705.0 ± 43.8 minutes, 640.0 ± 32.5 minutes). The duration of sensory and motor block in Group B (705.0 ± 43.8 minutes, 640.0 ± 32.5 minutes) was longer and statistically higher than group A (619.5 ± 48.0 minutes, 573.2 ± 31.5 minutes), the same trend was observed in group D (598.6 ± 53.2 minutes, 569.3 ± 39.9 minutes) over group C (537.0 ± 40.1 minutes, 479.0 ± 34.8 minutes) (P < 0.001, one-way ANOVA).

Conclusions:

The length of sensory and motor blockade is shorter in chronic opioid abusers. Adding 10 µg sufentanil to hyperbaric bupivacaine in opium abusers lengthened the sensory and motor block duration.

A randomized, double blind trial of prophylactic fibrinogen to reduce bleeding in cardiac surgery

BACKGROUND AND OBJECTIVES

Postoperative bleeding has a great clinical importance and can contribute to increased mortality and morbidity in patients undergoing coronary artery bypass graft surgery. In this prospective, randomized, double-blind study, we evaluated the effect of prophylactic administration of fibrinogen concentrate on post-coronary artery bypass graft surgery bleeding.

METHODS

A total of 60 patients undergoing coronary artery bypass surgery were randomly divided into two groups. Patients in the fibrinogen group received 1g of fibrinogen concentrate 30 min prior to the operation, while patients in the control group received placebo. Post-operative bleeding volumes, prothrombin time, partial thromboplastin time, INR, hemoglobin and transfused blood products in both groups were recorded. A strict red blood cell transfusion protocol was used in all patients.

RESULTS

There were no significant differences between intra-operative packed red blood cells infusion in the studied groups (1.0±1.4 in fibrinogen group, and 1.3±1.1 in control group). Less postoperative bleeding was observed in the fibrinogen group (477±143 versus 703±179, p=0.0001). Fifteen patients in the fibrinogen group and 21 in the control group required post-op packed red blood cells infusion (p=0.094). No thrombotic event was observed through 72 h after surgery.

CONCLUSION

Prophylactic fibrinogen reduces post-operative bleeding in patients undergoing coronary artery bypass graft.

Ondansetron reducing pain on injection of etomidate: a controlled randomized study

INTRODUCTION

Etomidate causes pain when injected intravenously. In this study we sought to determine if pretreatment by ondansetron reduces the pain on injection of etomidate.

METHODS

In this randomized, double blinded, placebo-controlled clinical trial, 20 patients of both sexes aged between 18 and 50 years of American Society of Anesthesiologists (ASA) physical status class I or II, whom were candidates for various elective surgical procedures and need more than one intravenous access were enrolled in the study. On arrival to the operating room two 22 gauge cannulas were inserted into veins on the dorsum of both hands. Following the infusion of 100mL normal saline into both intravenous lines, using an elastic band, venous drainage of hands was occluded at midarm. The patients were administered 8 mg (2 mL) of ondansetron into one hand and 2 mL of 0.9% saline into the other hand at the same time. The elastic band was removed after 1 min and 2mg (1 mL) of etomidate was administered at the same rate simultaneously into intravenous lines. The patients were asked to give a score of pain based on a verbal analog scale (VAS) to each hand.

RESULTS

A total number of 20 patients were studied (male = 55%, female = 45%). The mean age of the participants was 37.5 ± 13.1 years old and the mean weight was 67.7 ± 7.3 kg. The mean VAS for injection pain of etomidate after pre-administration of intravenous ondansetron was 1.5 ± 1.2 which was lower compared to pre-administration of placebo (3.2 ± 2.8, p < 0.05).

CONCLUSION

This study illustrates that pre-treatment with intravenous ondansetron significantly reduces the pain on injection of etomidate.