The Prevalence and Clinical Significance of Preoperative Thrombocytopenia in Adults Undergoing Elective Surgery: An Observational Cohort Study.

BACKGROUND: Preoperative thrombocytopenia is associated with inferior outcomes in surgical patients, though concurrent anemia may obfuscate these relationships. This investigation assesses the prevalence and clinical significance of preoperative thrombocytopenia with thorough consideration of preoperative anemia status. METHODS: This is an observational cohort study of adults undergoing elective surgery with planned postoperative hospitalization from January 1, 2009 to May 3, 2018. Patients were designated into 4 groups: normal platelet and hemoglobin concentrations, isolated thrombocytopenia (ie, platelet count <100 × 109/L), isolated anemia (ie, hemoglobin <12 g/dL women, <13.5 g/dL men), and thrombocytopenia with anemia. Thrombocytopenia was further defined as incidental (ie, previously undiagnosed) or nonincidental. Multivariable regression analyses were utilized to assess the relationships between thrombocytopenia status and clinical outcomes, with a primary outcome of hospital length of stay. RESULTS: A total of 120,348 patients were included for analysis: 72.3% (95% confidence interval [CI], 72.1-72.6) normal preoperative laboratory values, 26.3% (26.1-26.6) isolated anemia, 0.80% (0.75-0.86) thrombocytopenia with anemia, and 0.52% (0.48-0.56) isolated thrombocytopenia (0.38% [0.34-0.41] nonincidental, 0.14% [0.12-0.17] incidental). Thrombocytopenia was associated with longer hospital length of stay in those with concurrent anemia (multiplicative increase of the geometric mean 1.05 [1.00, 1.09] days; P = .034) but not in those with normal preoperative hemoglobin concentrations (multiplicative increase of the geometric mean 1.02 [0.96, 1.07] days; P = .559). Thrombocytopenia was associated with increased odds for intraoperative transfusion regardless of anemia status (nonanemic: 3.39 [2.79, 4.12]; P < .001 vs anemic: 2.60 [2.24, 3.01]; P < .001). Thrombocytopenia was associated with increased rates of intensive care unit (ICU) admission in nonanemic patients (1.56 [1.18, 2.05]; P = .002) but not in those with preoperative anemia (0.93 [0.73, 1.19]; P = .578). CONCLUSIONS: Preoperative thrombocytopenia is associated with clinical outcomes in elective surgery, both in the presence and absence of concurrent anemia. However, isolated thrombocytopenia is rare (0.5%) and is usually identified before preoperative testing. It is unlikely that routine thrombocytopenia screening is indicated for most patients.

Ocular injury during spine surgery.

PURPOSE: Ocular injury and vision loss are rare complications of surgery. Spine surgery has been identified as particularly high risk for postoperative vision loss; nevertheless, ocular injuries have not been comprehensively assessed in this patient population. METHODS: This historical cohort study assessed incidence, cause, and risk factors of perioperative ocular injury after spine surgery at a tertiary care medical centre from January 1, 2006 through January 31, 2018. Patients were included who had ocular injury identified during an ophthalmology consultation in the first seven postoperative days. Differences in demographic, laboratory, intraoperative, and postoperative characteristics between those experiencing or not experiencing ocular injury were assessed with Fisher exact and Wilcoxon signed-rank tests for categorical and continuous variables, respectively. RESULTS: Of 20,128 qualifying spine surgeries, 39 cases of perioperative ocular injuries were identified (39/20,128; 0.19% [95% confidence interval (CI), 0.14 to 0.26]). The most common ocular injury was blurry vision of unknown cause (13/39; 33%; 95% CI, 18.6 to 46.4), followed by ischemic optic neuropathy (9/39; 23%; 95% CI, 12.6 to 38.3) and corneal abrasion (7/39; 18%; 95% CI, 9.0 to 32.7). All cases of blurry vision of unknown cause were diagnosed via ophthalmology consultation and resolved within several days. Patients with perioperative ocular injury were more likely to have baseline anemia, have undergone fusion and instrumentation procedures, and had longer operative times with greater crystalloid, colloid, and transfusion requirements and more blood loss. CONCLUSIONS: Although not representing a causal relationship, these data suggest that surgical factors may have a greater role than demographic characteristics or other clinical factors in the development of perioperative ocular injury. Surgeons, anesthesiologists, and patients should be aware of the increased risk of ocular injury that accompanies longer, more extensive spine operations.

RéSUMé: OBJECTIF: Les lésions oculaires et la perte de vision sont des complications chirurgicales rares. La chirurgie du rachis a été identifiée comme une intervention entraînant un risque particulièrement élevé de perte de vision postopératoire; cependant, les lésions oculaires n'ont pas été évaluées de manière exhaustive chez cette population de patients. MéTHODE: Cette étude de cohorte historique a évalué l'incidence, la cause et les facteurs de risque de lésion oculaire périopératoire après une chirurgie du rachis dans un centre médical de soins tertiaires entre le 1er janvier 2005 et le 31 janvier 2018. Les patients ayant subi une lésion oculaire diagnostiquée lors d'une consultation en ophtalmologie au cours des sept premiers jours postopératoires ont été inclus. Les différences de caractéristiques démographiques, de laboratoire, peropératoires et postopératoires entre les patients ayant subi ou non une lésion oculaire ont été évaluées à l'aide du test exact de Fisher et du test des rangs signés de Wilcoxon pour les variables catégoriques et continues, respectivement. RéSULTATS: Parmi les 20 128 chirurgies du rachis éligibles, 39 cas de lésions oculaires périopératoires ont été identifiés (39/20,128; 0,19 % [intervalle de confiance (IC) 95 %, 0,14 à 0,26]). La lésion oculaire la plus fréquente était une vision floue de cause inconnue (13/39; 33 %; IC 95 %, 18,6 à 46,4), suivie d'une neuropathie optique ischémique (9/39; 23 %; IC 95 %, 12,6 à 38,3) et d'une abrasion cornéenne (7/39; 18 %; IC 95 %, 9,0 à 32,7). Tous les cas de vision floue de cause inconnue ont été diagnostiqués lors d'une consultation en ophtalmologie et se sont résolus après plusieurs jours. Les patients ayant subi une lésion oculaire périopératoire étaient plus susceptibles de présenter une anémie de départ, d'avoir subi des interventions de fusion et instrumentation rachidiennes, et d'avoir subi une chirurgie plus longue nécessitant davantage de cristalloïdes, de colloïdes et de transfusions, ainsi que d'avoir subi des pertes sanguines plus importantes. CONCLUSION: Bien que n'établissant pas de relation causale, ces données suggèrent que les facteurs chirurgicaux pourraient jouer un rôle plus important que les caractéristiques démographiques ou les autres facteurs cliniques dans l'apparition d'une lésion oculaire périopératoire. Chirurgiens, anesthésiologistes et patients devraient être conscients du risque accru de lésion oculaire qui accompagne les opérations du rachis plus longues et plus importantes.

The order of vasopressor discontinuation and incidence of hypotension: a retrospective cohort analysis.

The optimal order of vasopressor discontinuation during shock resolution remains unclear. We evaluated the incidence of hypotension in patients receiving concomitant vasopressin (VP) and norepinephrine (NE) based on the order of their discontinuation. In this retrospective cohort study, consecutive patients receiving concomitant VP and NE infusions for shock admitted to intensive care units were evaluated. The primary outcome was hypotension incidence following discontinuation of VP or NE (VP1 and NE1 groups, respectively). Secondary outcomes included the incidence of acute kidney injury (AKI) and arrhythmias. Subgroup analysis was conducted by examining outcomes based on the type of shock. Of the 2,035 included patients, 952 (46.8%) were VP1 and 1,083 (53.2%) were NE1. VP1 had a higher incidence of hypotension than NE1 (42.1% vs. 14.2%; P < 0.001), longer time to shock reversal (median: 2.5 vs. 2.2 days; P = .009), higher hospital [29% (278/952) vs. 24% (258/1083); P = .006], and 28-day mortality [37% (348/952) vs. 29% (317/1,083); P < 0.001] when compared with the NE1 group. There were no differences in ICU mortality, ICU and hospital length of stay, new-onset arrhythmia, or AKI incidence between the two groups. In subgroup analyses based on different types of shock, similar outcomes were observed. After adjustments, hypotension in the following 24 h and 28-day mortality were significantly higher in VP1 (Odds ratios (OR) 4.08(3.28, 5.07); p-value < .001 and 1.27(1.04, 1.55); p-value < .001, respectively). Besides, in a multivariable model, the need for renal replacement therapy (OR 1.68 (1.34, 2.12); p-value < .001) was significantly higher in VP1. Among patients with shock who received concomitant VP and NE, the VP1 group was associated with a higher incidence of hypotension in comparison with NE1. Future studies need to validate our findings and their impact on clinical outcomes.

Intravenous Versus Oral Acetaminophen in Outpatient Cystoscopy Procedures: Retrospective Comparison of Postoperative Opioid Requirements and Analgesia Scores.

PURPOSE: To assess if the choice of acetaminophen formulation (intravenous vs oral) when administered preoperatively for ambulatory cystoscopy procedures is associated with differences in anesthetic outcomes. METHODS: Medical records of adult patients undergoing ambulatory cystoscopy procedures at an outpatient procedural center from July 1, 2014, through November 30, 2017, were abstracted. The association between anesthetic outcomes (severe pain, rescue opioids, postoperative nausea, and vomiting) and acetaminophen formulation was assessed. Propensity-adjusted analyses were performed using inverse probability of treatment weighting to account for potential confounders. RESULTS: During the study time frame, there were 611 intravenous and 2955 oral acetaminophen administrations for cystoscopy procedures. Postoperative bladder spasms were a major contributor to severe pain and complicated 1036 cases, with similar rates between intravenous (N = 183, 29.9%) and oral (N = 853, 28.9%) formulations, P = .625. After adjusting for bladder spasms, intravenous acetaminophen was associated with longer anesthesia recovery (estimate 5.2 [95% CI 0.5-9.9] minutes, P = .030), use of rescue opioids (odds ratio 1.33 [1.07-1.66], P = .012), and postoperative nausea and vomiting (1.40 [1.02-1.93], P = .037), but not severe pain (1.07 [0.81-1.40], P = .640). CONCLUSION: Preoperative intravenous acetaminophen compared to oral acetaminophen for ambulatory cystoscopy procedures was not associated with better anesthetic outcomes. Bladder spasms were a major contributor to postoperative pain.