Update on the Diagnosis and Management of Acute Colonic Pseudo-obstruction (ACPO).

PURPOSE OF REVIEW: Acute Colonic Pseudo-obstruction (ACPO) is a cause of large intestinal dilation and obstruction without any physical transition point. It remains difficult to diagnose and treat. We review the recent updates on diagnosis and management of ACPO. RECENT FINDINGS: Recent guidelines have posited that conservative management can be tried in most cases of ACPO, but that early decompression and surgery should be considered. Use of neostigmine is still a viable option but there is also promising data on pyridostigmine as well as prucalopride. Resolution of ACPO should be followed by daily use of polyethylene glycol (PEG) to help prevent recurrence. ACPO warrants early and accurate diagnosis with exclusion of alternate causes of large bowel dilation. Conservative management can be attempted for 48-72 h in those with cecal diameters < 12 cm and without signs of peritonitis and perforation. Early escalation of management should be attempted with neostigmine followed by endoscopy and/or surgery as needed, given that longer periods of dilation are associated with worse outcomes. There is promising new evidence for use of pyridostigmine and prucalopride, but further trials are needed prior to incorporating them into regular use. Finally, studies are lacking regarding prevention of ACPO after initial resolution.

Comparing the Effect of Neostigmine and Metoclopramide on Gastric Residual Volume of Mechanically Ventilated Patients in Intensive Care Unit: A Double-Blind Randomized Clinical Trial.

INTRODUCTION: The gastric residual volume (GRV) monitoring in patients with mechanical ventilation (MV) is a common and important challenge. The purpose of this study was to compare the effect of neostigmine and metoclopramide on GRV among MV patients in the intensive care unit (ICU). METHODS: In a double-blind randomized clinical trial, a total of 200 mechanically ventilated ICU patients with GRV > 120 ml (6 hours after the last gavage) were randomly assigned into two groups (A and B) with 100 patients in each group. Patients in groups A and B received intravenous infusion of neostigmine at a dose of 2.5 mg/100 ml normal saline and metoclopramide at a dose of 10 mg/100 ml normal saline, within 30 minutes, respectively. GRV was evaluated 5 times for each patient, once before the intervention and 4 times (at 3, 6, 9, and 12 hours) after the intervention. In addition, demographic characteristics including age and gender, as well as severity illness based on the sequential organ failure assessment score (SOFA), were initially recorded for all patients. RESULTS: After adjusting of demographic and clinical characteristics (age, gender, and SOFA score), the generalized estimating equation (GEE) model revealed that neostigmine treatment increased odds of GRV improvement compared to the metoclopramide group (OR = 2.45, 95% CI: 1.60-3.76, P < 0.001). However, there is a statistically significant time trend (within-subject differences or time effect) regardless of treatment groups (P < 0.001). CONCLUSION: According to the results, although neostigmine treatment significantly improved GRV in more patients in less time, within 12 hours of treatment, all patients in both groups had complete recovery. Considering that there was no significant difference between the two groups in terms of side effects, it seems that both drugs are effective in improving the GRV of ICU patients.

Postoperative interventions for preventing bladder dysfunction after radical hysterectomy in women with early-stage cervical cancer.

BACKGROUND: Bladder dysfunction is a common complication following radical hysterectomy, caused by the damage to pelvic autonomic nerves that innervate the muscles of the bladder, urethral sphincter, and pelvic floor fasciae. Bladder dysfunction increases the rates of urinary tract infection, hospital visits or admission, and patient dissatisfaction. In addition, bladder dysfunction can also negatively impact patient quality of life (QoL). Several postoperative interventions have been proposed to prevent bladder dysfunction following radical hysterectomy. To our knowledge, there has been no systematic review evaluating the effectiveness and safety of these interventions for preventing bladder dysfunction following radical hysterectomy in women with cervical cancer. OBJECTIVES: To evaluate the effectiveness and safety of postoperative interventions for preventing bladder dysfunction following radical hysterectomy in women with early-stage cervical cancer (stage IA2 to IIA2). SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 4) in the Cochrane Library, MEDLINE via Ovid (1946 to April week 2, 2020), and Embase via Ovid (1980 to 2020, week 16). We also checked registers of clinical trials, grey literature, conference reports, and citation lists of included studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) evaluating the effectiveness and safety of any type of postoperative interventions for preventing bladder dysfunction following a radical hysterectomy in women with stage IA2 to IIA2 cervical cancer. DATA COLLECTION AND ANALYSIS: Two review authors independently selected potentially relevant RCTs, extracted data, assessed risk of bias, compared results, and made judgments on the quality and certainty of the evidence. We resolved any disagreements through discussion or consultation with a third review author. Outcomes of interest consisted of spontaneous voiding recovery one week after the operation, quality of life (QoL), adverse events, post-void residual urine volume one month after the operation, urinary tract infection over the one month following the operation, and subjective urinary symptoms. MAIN RESULTS: We identified 1464 records as a result of the search (excluding duplicates). Of the 20 records that potentially met the review criteria, we included five reports of four studies. Most of the studies had unclear risks of selection and reporting biases. Of the four studies, one compared bethanechol versus placebo and three studies compared suprapubic catheterisation with intermittent self-catheterisation. We identified two ongoing studies. Bethanechol versus placebo The study reported no information on the rate of spontaneous voiding recovery at one week following the operation, QoL, adverse events, urinary tract infection in the first month after surgery, and subjective urinary symptoms for this comparison. The volume of post-void residual urine, assessed at one month after surgery, among women receiving bethanechol was lower than those in the placebo group (mean difference (MD) -37.4 mL, 95% confidence interval (CI) -60.35 to -14.45; one study, 39 participants; very-low certainty evidence). Suprapubic catheterisation versus intermittent self-catheterisation The studies reported no information on the rate of spontaneous voiding recovery at one week and post-void residual urine volume at one month following the operation for this comparison. There was no difference in risks of acute complication (risk ratio (RR) 0.77, 95% CI 0.24 to 2.49; one study, 71 participants; very low certainty evidence) and urinary tract infections during the first month after surgery (RR 0.77, 95% CI 0.53 to 1.13; two studies, 95 participants; very- low certainty evidence) between participants who underwent suprapubic catheterisation and those who underwent intermittent self-catheterisation. Available data were insufficient to calculate the relative measures of the effect of interventions on QoL and subjective urinary symptoms. AUTHORS' CONCLUSIONS: None of the included studies reported rate of spontaneous voiding recovery one week after surgery, time to a post-void residual volume of urine of 50 mL or less, or post-void residual urine volume at 6 and 12 months after surgery, all of which are important outcomes for assessing postoperative bladder dysfunction. Limited evidence suggested that bethanechol may minimise the risk of bladder dysfunction after radical hysterectomy by lowering post-void residual urine volume. The certainty of this evidence, however, was very low. The effectiveness of different types of postoperative urinary catheterisation (suprapubic and intermittent self-catheterisation) remain unproven.

Association between normal tension glaucoma and the risk of Alzheimer's disease: a nationwide population-based cohort study in Taiwan.

OBJECTIVES: To investigate a possible association between normal tension glaucoma (NTG) and an increased risk of developing Alzheimer's disease (AD). DESIGN: Retrospective cohort study. SETTING: NTG group and the comparison group were retrieved from the whole population of the Taiwan National Health Insurance Research Database from 1 January 2001 to 31 December 2013. PARTICIPANTS: A total of 15 317 subjects with NTG were enrolled in the NTG group, and 61 268 age-matched and gender-matched subjects without glaucoma were enrolled in the comparison group. PRIMARY AND SECONDARY OUTCOME MEASURES: Kaplan-Meier curves were generated to compare the cumulative hazard of AD between the two groups. A multivariable Cox regression analysis was used to estimate the adjusted hazard ratios (HRs) of AD, adjusted for diabetes, hypertension, hyperlipidaemia, coronary artery disease and stroke. Furthermore, risk factors for developing AD among the NTG group were investigated. RESULTS: The mean age of the cohort was 62.1±12.5 years. Patients with NTG had significantly higher proportions of diabetes, hypertension, hyperlipidaemia, coronary artery disease and stroke than the comparisons. Patients with NTG had a significantly higher cumulative hazard for AD than the comparisons (p<0.0001). In the multivariable Cox regression after adjustment for confounders, the NTG group had a significantly higher risk of AD (adjusted HR 1.52; 95% CI 1.41 to 1.63). Moreover, in the NTG group, when we compared the effects of different types of glaucoma eye drops, none of the eye drops used were significant risk factors or protective factors for AD. CONCLUSIONS: People with NTG are at a significantly greater risk of developing AD compared with individuals without glaucoma. Among patients with NTG, none of the glaucoma eye drops used significantly changed the risk of subsequent AD.

Neostigmine and glycopyrronium: a potential safe alternative for patients with pseudo-obstruction without access to conventional methods of decompression.

Intestinal pseudo-obstruction mimics bowel obstruction. However, on examination, no mechanical cause is identified. This condition will often resolve when managed conservatively, yet in some cases decompression is required to avoid the serious complications of bowel ischaemia and perforation. This is performed endoscopically, and due to the invasive nature and limited access to this service, an alternative treatment option is deemed appealing. Neostigmine has good efficacy in the decompression of pseudo-obstruction but is hindered by its wide side effect profile. In this context, neostigmine requires careful monitoring, which limits its appeal. This side effect profile is minimised when neostigmine is administered in conjunction with glycopyrronium.This case demonstrates the novel use of neostigmine and glycopyrronium in decompression of the bowel in a patient with pseudo-obstruction. Furthermore, it highlights its value, particularly when conventional techniques for decompression are not accessible.

Use of neuromuscular blockers and neostigmine for general anesthesia and its association with neuraxial blockade: A retrospective study.

This research aimed to assess the use of neuromuscular blockers (NMB) and its reversal, associated or not with neuraxial blockade, after general anesthesia.This retrospective study analyzed 1295 patients that underwent surgery with general anesthesia at Prof. Dr. José Aristodemo Pinotti Hospital in 2013. The study included patients aged >1 year, with complete, readable medical charts and anesthetic records.Rocuronium (ROC) was the most used NMB (96.7%), with an initial dose of 0.60 (0.52-0.74) mg/kg and total dose of 0.38 (0.27-0.53) mg/kg/h. In 24.3% of the cases, neuraxial blockade was associated with a significantly longer anesthesia (P < .001) than in cases without neuraxial block, regardless of technique (total intravenous (TIV) vs intravenous and inhalational (IV+IN)). In 71.9% of the cases, a single dose of NMB was used. Patients under TIV general anesthesia associated with neuraxial blockade had a lower total dose of ROC (mg/kg/h) in comparison with TIV GA alone (0.30 (0.23-0.39) and 0.42 (0.30-0.56) mg/kg/h, respectively, P < .001). The same was observed for patients under IV+IN GA (0.32 (0.23-0.41) and 0.43 (0.31-0.56) mg/kg/h, respectively, P < .001). The duration of anesthesia was longer according to increasing number of additional NMB doses (P < .001). Dose of neostigmine was 2.00 (2.00-2.00) mg or 29.41 (25.31-33.89) µg/kg. The interval between neostigmine and extubation was >30 minutes in 10.9% of cases.The most widely used NMB was ROC. Neuroaxial blockade (spinal or epidural) was significantly associated with reduced total dose of ROC (mg/kg/h) during general anesthesia, even in the absence of neuromuscular monitoring and regardless of general anesthetic technique chosen. In most cases, neostigmine was used to reverse neuromuscular block. The prolonged interval between neostigmine and extubation (>30 minutes) was neither associated with total doses of ROC or neostigmine, nor with the time of NMB administration. This study corroborates the important role of quantitative neuromuscular monitors and demonstrates that neuraxial blockade is associated with reduced total ROC dose. Further studies are needed to evaluate the possible role of neuraxial blockade in reducing the incidence of postoperative residual curarization.

Danish Nationwide Data Reveal a Link between Diabetes Mellitus, Diabetic Retinopathy, and Glaucoma.

Aims. To determine the association between treatment against diabetes mellitus (DM) and treatment with antiglaucomatous drugs in the entire Danish population and to investigate the comorbidity between DM and its complications with antiglaucomatous treatment. Methods. Retrospective nationwide cohort study with data over a 16-year follow-up period. The National Danish Registry of Medicinal Products Statistics was used to identify all claimed prescriptions for antiglaucomatous medication and DM drugs. ICD-10 classifications were furthermore used to identify comorbidities between antiglaucomatous medication and the DM complications, diabetic retinopathy (DR), and nephropathy. Results. A total of 6,343,747 individuals in the period between 1996 and 2012 were analyzed. The overall incidence rate of new-onset glaucoma patients was 0.07 per 1000 person-years for the reference population compared to 36 per 1000 person-years for all diagnosed DM cases. Patients treated with DM drugs had about two times higher relative risk of glaucoma, when adjusting for a range of factors. The presence of DR alone or in combination with nephropathy increased the risk of glaucoma. Conclusions. The present study reports a strong association between DM and onset of glaucoma treatment in the entire Danish population.

Parasympathomimetic drugs for dry mouth due to radiotherapy.

Data sourcesCochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials, Medline, Embase and CINAHL databases. Reference lists of identified articles were checked and experts in the field and relevant pharmaceutical companies were contacted.Study selectionRandomised controlled trials, including parallel and crossover, carried out in any setting on any patient population with radiation-induced salivary dysfunction using parasympathomimetics drugs.Data extraction and synthesisThe two authors independently assessed for inclusion, established the risk of bias and abstracted data. The primary outcome was level of xerostomia. The authors intended to report risk ratio, odds ratio, risk difference and NNT for dichotomous data and mean difference and standard mean difference for continuous data.ResultsOf the three included studies, one (n=20) reported mean improvement on the VAS (22.5 mm on a 100 mm scale). The other two studies considered a change in 25 mm on the VAS a positive response. Of those one (n=207) reported positive response in 51% of subjects on 5mg of pilocapine TID and 47% for 10mg TID. The second (n= 162) reported a 42% positive response with a titrated dose regimen. The side effects rate was high,and the main reason for discontinuation.ConclusionsThere is limited evidence to support the use of pilocarpine hydrochloride in the treatment of radiation-induced xerostomia. Currently, there is little evidence to support the use of other parasympathomimetic drugs in the treatment of radiation-induced xerostomia. Available studies suggest that approximately half of patients will respond, but side effects can be problematic. The conclusions of the update are the same as the conclusions of the original review, since no new relevant studies have been published in the interim.

Comparison of neostigmine and sugammadex for hemodynamic parameters in cardiac patients undergoing noncardiac surgery.

STUDY OBJECTIVE: The aim of this study is to compare the hemodynamic effects of neostigmine-atropine combination and sugammadex in patients with cardiac problems undergoing noncardiac surgery. DESIGN: Prospective randomized study. SETTING: In the operating room. PATIENTS: Ninety patients with a class 2 or 3 cardiovascular disease according to the New York Heart Association classification and aged between 18 and 75 years undergoing noncardiac surgery were randomized. INTERVENTIONS: Group N (n = 45) received 0.03 mg/kg IV neostigmine when T2 appeared as measured with a nerve muscle stimulator. When heart rate was 5 beats/min (±10 beats/min) lower than the heart rate before administration of the medication, 0.5 mg IV atropine sulfate was given. Group S (n = 45) received 3 mg/kg IV sugammadex when T2 appeared as measured with a nerve muscle stimulator. MEASUREMENTS: Heart rate, mean systolic and diastolic blood pressures, and electrocardiographic alterations including the QTc (QT Fredericia and QT Bazett) were recorded. MAIN RESULTS: There were no significant differences between and within the groups in terms of QTc values. Sugammadex group had a significant decrease on heart rate 1 minute after the medication when compared to the measurement before the medication (P < .05). Heart rate and systolic blood pressure increased in neostigmine group 3 minutes after the medication and during postoperative measurements (P < .05). Sugammadex group had lower systolic, diastolic, and mean blood pressures and heart rate when compared to neostigmine group (P < .05). CONCLUSIONS: We suggest that sugammadex might be preferred as it provides more hemodynamic stability compared to neostigmine-atropine combination to reverse rocuronium-induced neuromuscular blockage in cardiac patients undergoing noncardiac surgery.

Ogilvie's Syndrome.

Ogilvie's syndrome, also known as 'paralytic ileus of the colon', is characterised by pseudo-obstruction of the large intestine in the absence of any mechanical obstructing component; and presents as a massively distended abdomen. If left untreated, it may lead to bowel perforation or ischemia. Ogilvie's syndrome usually presents as a postsurgical complication, mainly due to the lack and/or restriction of movement coupled with a possible electrolyte imbalance. Here, we present a case of a pre-surgical 63-year lady, having a right hip fracture, who came with complaints of severe abdominal pain and distension for 4 days. Abdominal X-rays showed massively dilated bowel loops. Patient was successfully managed with neostigmine administration and was discharged home.

Impact of treatment strategies for open angle glaucoma on intraocular pressure: the RiGOR study.

AIMS: The RiGOR study's primary outcome measure was a 15% reduction in intraocular pressure (IOP) for patients with open-angle glaucoma at 1 year. METHODS: Patients received treatment according to the ophthalmologist's usual practice. RESULTS: A higher proportion of patients in the incisional and other surgery group achieved a 15% reduction in IOP than in the laser surgery or additional medication groups (82, 57, and 57% respectively). In multivariate regression analyses, incisional surgery patients were 2.7-times as likely as patients treated with additional medication to achieve a 15% reduction in IOP (odds ratio: 2.67; 95% CI: 2.01-3.57). CONCLUSION: Incisional and other surgical procedures are effective treatments. There were no differences in treatment response by race or ethnicity.

Intraocular pressure changes associated with tracheal extubation: Comparison of sugammadex with conventional reversal of neuromuscular blockade.

OBJECTIVE: To compare the effects of neostigmine/atropine combination and sugammadex on intraocular pressure during tracheal extubation period. METHODS: The single-blind prospective randomised controlled study was conducted at Ordu University Research and Training Hospital from August to October 2014, and comprised patients who were randomly assigned to 2 groups according to the agent used for reversal of neuromuscular blockade. Group N received 0.05mgkg-1 neostigmine and 0.02 mgkg-1 atropine and the patients in Group S received 2mgkg-1 sugammadex intravenously. Heart rate, mean arterial pressure and intraocular pressure were measured at baseline, before the induction (T1), after the application of reversal agent (T2), and 1 (T3), 3 (T4), 5 (T5) and 10 (T6) minutes after the extubation. SPSS 16 was used for statistical analysis. RESULTS: There were 36 patients in the study; 18(50%) in each group. There was no significant difference between the groups in terms of age, gender and body mass index (p>0.05 each). Intraocular pressure was significantly higher when the baseline level was compared with all measurement intervals in Group N (p<0.05 each). In Group S, it showed no significant difference at T2 (p>0.05) whereas it was significantly higher at all other measurement intervals (p<0.05 each). Intergroup comparisons showed statistically significant difference in heart rate and mean arterial pressure levels at T2 interval which were higher in Group N (p<0.01). Intraocular pressure levels at T2 and T3 intervals were significantly higher in Group N (p<0.01). CONCLUSIONS: Lower end-extubation intraocular pressure levels were obtained when sugammadex was used as a neuromuscular block reversal agent in comparison with neostigmine-atropine combination. Sugammadex may be a better option for the reversal of neuromuscular blockade and intraocular pressure increase should be avoided in patients with glaucoma or penetrating eye injury.

Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy.

BACKGROUND: This is an updated version of the original Cochrane review on parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (published in Issue 3, 2007). Salivary gland dysfunction is a predictable side effect of radiotherapy to the head and neck region. Pilocarpine hydrochloride (a choline ester) is licensed in many countries for the treatment of radiation-induced salivary gland dysfunction. Other parasympathomimetics have also been used 'off licence' in the treatment of this condition. OBJECTIVES: To determine the efficacy and tolerability of parasympathomimetic drugs in the treatment of radiation-induced salivary gland dysfunction (specifically radiation-induced xerostomia). SEARCH METHODS: For this update, we ran searches of the Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 6), MEDLINE, EMBASE, and CINAHL in July 2015. We checked the reference lists of retrieved articles for additional studies, contacted experts in the field for unpublished and ongoing trials, and contacted relevant pharmaceutical companies for unpublished and ongoing trials. SELECTION CRITERIA: The selection criteria for the review were: 1) randomised controlled trials; 2) people suffering from radiation-induced salivary gland dysfunction; 3) people treated with parasympathomimetic drugs; and 4) assessable data available on primary outcome measure. DATA COLLECTION AND ANALYSIS: The two review authors independently collected data from the full-text version of relevant papers including: 1) citation details; 2) participants; 3) interventions; 4) assessments; 5) outcomes (that is efficacy, tolerability); and 6) quality issues.Due to a lack of appropriate data, we were unable to perform a meta-analysis. MAIN RESULTS: In the original review, three studies, including a total of 298 participants, fulfilled the inclusion criteria. All three studies involved the use of pilocarpine hydrochloride. We have included no additional studies in the update of the review; we have excluded eight additional studies.The data suggest that pilocarpine hydrochloride is more effective than placebo and at least as effective as artificial saliva. The response rate was 42% to 51%. The time to response was up to 12 weeks. The overall side effect rate was high, and side effects were the main reason for withdrawal (6% to 15% of participants taking 5 mg three times a day had to withdraw). The side effects were usually the result of generalised parasympathomimetic stimulation (for example sweating, headaches, urinary frequency, vasodilatation). Response rates were not dose dependent, but side effect rates were dose dependent. AUTHORS' CONCLUSIONS: There is limited evidence to support the use of pilocarpine hydrochloride in the treatment of radiation-induced xerostomia. Currently, there is little evidence to support the use of other parasympathomimetic drugs in the treatment of radiation-induced xerostomia. Available studies suggest that approximately half of patients will respond, but side effects can be problematic. The conclusions of the update are the same as the conclusions of the original review, since no new relevant studies have been published in the interim.

Acute colonic pseudo-obstruction in pregnancy.

BACKGROUND: Acute colonic pseudo-obstruction is an uncommon but potentially morbid complication of pregnancy. The aim of the study was to review a single institution's experience with acute colonic pseudo-obstruction in post-partum patients and develop an algorithm for management based on a literature review. METHODS: This is a retrospective study where patients were identified over a 2-year period (1 December 2012 to 31 November 2014) by checking all deliveries in Christchurch Women's Hospital against diagnosis codes for bowel obstruction and ileus. Clinical records and radiology were then reviewed to identify those with acute colonic pseudo-obstruction and the management of these patients was reviewed. RESULTS: Over the study period, seven patients were identified from 10,240 deliveries. Two patients required laparotomy and the rest resolved without surgical intervention. One patient was treated with neostigmine and three with erythromycin. One patient had an unsuccessful attempt at endoscopic decompression, however, symptoms resolved without further intervention following this. A management algorithm was developed based on the literature review. CONCLUSIONS: Acute colonic pseudo-obstruction occurs in post-partum patients more frequently than suspected (one in 1500 deliveries). The management needs to be active with early correction of electrolyte abnormalities, avoidance of narcotic pain relief and early mobilization. Timely administration of neostigmine or endoscopic decompression can reduce the incidence of colonic ischaemia and perforation and the need for surgical intervention.

Ogilvie's syndrome-acute colonic pseudo-obstruction.

Ogilvie's syndrome describes an acute colonic pseudo-obstruction (ACPO) consisting of dilatation of part or all of the colon and rectum without intrinsic or extrinsic mechanical obstruction. It often occurs in debilitated patients. Its pathophysiology is still poorly understood. Since computed tomography (CT) often reveals a sharp transition or "cut-off" between dilated and non-dilated bowel, the possibility of organic colonic obstruction must be excluded. If there are no criteria of gravity, initial treatment should be conservative or pharmacologic using neostigmine; decompression of colonic gas is also a favored treatment in the decision tree, especially when cecal dilatation reaches dimensions that are considered at high risk for perforation. Recurrence is prevented by the use of a multiperforated Faucher rectal tube and oral or colonic administration of polyethylene glycol (PEG) laxative. Alternative therapeutic methods include: epidural anesthesia, needle decompression guided either radiologically or colonoscopically, or percutaneous cecostomy. Surgery should be considered only as a final option if medical treatments fail or if colonic perforation is suspected; surgery may consist of cecostomy or manually-guided transanal pan-colorectal tube decompression at open laparotomy. Surgery is associated with high rates of morbidity and mortality.

Effects of neostigmine reversal of nondepolarizing neuromuscular blocking agents on postoperative respiratory outcomes: a prospective study.

BACKGROUND: We tested the hypothesis that neostigmine reversal of neuromuscular blockade reduced the incidence of signs and symptoms of postoperative respiratory failure. METHODS: We enrolled 3,000 patients in this prospective, observer-blinded, observational study. We documented the intraoperative use of neuromuscular blocking agents and neostigmine. At postanesthesia care unit admission, we measured train-of-four ratio and documented the ratio of peripheral oxygen saturation to fraction of inspired oxygen (S/F). The primary outcome was oxygenation at postanesthesia care unit admission (S/F). Secondary outcomes included the incidence of postoperative atelectasis and postoperative hospital length of stay. Post hoc, we defined high-dose neostigmine as more than 60 µg/kg and unwarranted use of neostigmine as neostigmine administration in the absence of appropriate neuromuscular transmission monitoring. RESULTS: Neostigmine reversal did not improve S/F at postanesthesia care unit admission (164 [95% CI, 162 to 164] vs. 164 [161 to 164]) and was associated with an increased incidence of atelectasis (8.8% vs. 4.5%; odds ratio, 1.67 [1.07 to 2.59]). High-dose neostigmine was associated with longer time to postanesthesia care unit discharge readiness (176 min [165 to 188] vs. 157 min [153 to 160]) and longer postoperative hospital length of stay (2.9 days [2.7 to 3.2] vs. 2.8 days [2.8 to 2.9]). Unwarranted use of neostigmine (n = 492) was an independent predictor of pulmonary edema (odds ratio, 1.91 [1.21 to 3.00]) and reintubation (odds ratio, 3.68 [1.10 to 12.4]). CONCLUSIONS: Neostigmine reversal did not affect oxygenation but was associated with increased atelectasis. High-dose neostigmine or unwarranted use of neostigmine may translate to increased postoperative respiratory morbidity.