2020
Incidence, predictors, and timing of post-operative stroke following elective total hip arthroplasty and total knee arthroplasty
Haynes MS, Alder KD, Bellamkonda K, Kuzomunhu L, Grauer JN. Incidence, predictors, and timing of post-operative stroke following elective total hip arthroplasty and total knee arthroplasty. PLOS ONE 2020, 15: e0239239. PMID: 32941539, PMCID: PMC7498016, DOI: 10.1371/journal.pone.0239239.Peer-Reviewed Original ResearchConceptsTotal knee arthroplastyTotal hip arthroplastyIndependent risk factorPostoperative day twoPostoperative strokeKnee arthroplastyRisk factorsHip arthroplastyElective primary total hip arthroplastyTHA/TKANational Surgical Quality Improvement databaseElective total hip arthroplastyDay twoPrimary total hip arthroplastyPostoperative day ninePost-operative strokeTiming of strokeHigher American SocietyIncidence of strokePostoperative day oneMajority of strokesQuality improvement databaseRetrospective comparative studyAnesthesiologists (ASA) scoreCouncil patientsPreoperative High, as well as Low, Platelet Counts Correlate With Adverse Outcomes After Elective Total Hip Arthroplasty
Malpani R, Bovonratwet P, Clark MG, Ottesen TD, Mercier MR, Grauer JN. Preoperative High, as well as Low, Platelet Counts Correlate With Adverse Outcomes After Elective Total Hip Arthroplasty. JAAOS Global Research And Reviews 2020, 4: e20.00049. PMID: 32890010, PMCID: PMC7470002, DOI: 10.5435/jaaosglobal-d-20-00049.Peer-Reviewed Original ResearchMeSH KeywordsArthroplasty, Replacement, HipElective Surgical ProceduresHumansLength of StayPatient ReadmissionPlatelet CountConceptsTotal hip arthroplastyNational Surgical Quality Improvement Program databaseQuality Improvement Program databasePreoperative platelet countAbnormal platelet countImprovement Program databasePlatelet countPerioperative complicationsAdverse eventsHospital readmissionTHA patientsAdverse outcomesProgram databaseHip arthroplastyElective primary total hip arthroplastyElective total hip arthroplastyPrimary total hip arthroplastyMulticenter patient populationPreoperative laboratory studiesMinor adverse eventsPostoperative adverse eventsLow platelet countPostoperative complication dataNormal platelet countHigher platelet countsOrthopedics in the Era of COVID-19.
Halim A, Grauer JN. Orthopedics in the Era of COVID-19. Orthopedics 2020, 43: 138-139. PMID: 32421197, DOI: 10.3928/01477447-20200426-01.Commentaries, Editorials and LettersUnderweight patients are at just as much risk as super morbidly obese patients when undergoing anterior cervical spine surgery
Ottesen TD, Malpani R, Galivanche AR, Zogg CK, Varthi AG, Grauer JN. Underweight patients are at just as much risk as super morbidly obese patients when undergoing anterior cervical spine surgery. The Spine Journal 2020, 20: 1085-1095. PMID: 32194246, PMCID: PMC7380546, DOI: 10.1016/j.spinee.2020.03.007.Peer-Reviewed Original ResearchConceptsAnterior cervical spine surgeryBody mass indexCervical spine surgeryNational Surgical Quality Improvement Program databaseSuper morbidly obese patientsQuality Improvement Program databaseWorld Health Organization categoriesMorbidly obese patientsImprovement Program databaseObese patientsAdverse eventsAdverse outcomesSpine surgeryUnderweight patientsPostoperative infectionProgram databaseSurgeons National Surgical Quality Improvement Program databaseMultivariate analysisAnterior cervical spine proceduresOverweight/obese categoriesThirty-day adverse eventsHigher body mass indexLower body mass indexAdverse outcome categoriesNormal BMI patientsHigh, As Well As Low, Preoperative Platelet Counts Correlate With Adverse Outcomes After Elective Posterior Lumbar Surgery.
Malpani R, Gala RJ, Adrados M, Galivanche AR, Clark MG, Mercier MR, Pathak N, Mets EJ, Grauer JN. High, As Well As Low, Preoperative Platelet Counts Correlate With Adverse Outcomes After Elective Posterior Lumbar Surgery. Spine 2020, 45: 349-356. PMID: 32045405, DOI: 10.1097/brs.0000000000003248.Peer-Reviewed Original ResearchConceptsPosterior lumbar surgeryPreoperative platelet countLow platelet countPlatelet countLumbar surgeryAdverse outcomesAdverse eventsHospital lengthNational Surgical Quality Improvement Program databaseLow preoperative platelet countPreoperative low platelet countQuality Improvement Program databaseHigh platelet groupLonger hospital lengthLumbar surgery patientsPerioperative adverse outcomesMinor adverse eventsPostoperative adverse eventsImprovement Program databaseRetrospective cohort studyHigher platelet countsLarger patient populationPostoperative complicationsCohort studyPlatelet group
2019
Admission NarxCare Narcotics Scores are not Associated With Adverse Surgical Outcomes or Self-reported Patient Satisfaction Following Elective Spine Surgery.
Galivanche AR, Mercier MR, Adrados M, Pathak N, McLynn RP, Anandasivam NS, Varthi AG, Rubin LE, Grauer JN. Admission NarxCare Narcotics Scores are not Associated With Adverse Surgical Outcomes or Self-reported Patient Satisfaction Following Elective Spine Surgery. Spine 2019, 44: 1515-1522. PMID: 31356498, DOI: 10.1097/brs.0000000000003120.Peer-Reviewed Original ResearchConceptsMultivariate logistic regressionPatient satisfactionAdverse eventsNarcotic scoreSurvey response rateSpine surgeryResponse rateLogistic regressionSelf-reported patient satisfactionElective spine surgeryPreoperative opioid usePostoperative patient satisfactionTime of admissionAdverse surgical outcomesSpine surgery casesHospital Consumer AssessmentHCAHPS survey resultsDifferent narcoticsNarcotic usagePerioperative outcomesNarcotic utilizationOpioid usePatient characteristicsPostoperative outcomesNarcotic groupAbnormally High, as Well as Low, Preoperative Platelet Counts Correlate With Adverse Outcomes and Readmissions After Elective Total Knee Arthroplasty
Malpani R, Haynes MS, Clark MG, Galivanche AR, Bovonratwet P, Grauer JN. Abnormally High, as Well as Low, Preoperative Platelet Counts Correlate With Adverse Outcomes and Readmissions After Elective Total Knee Arthroplasty. The Journal Of Arthroplasty 2019, 34: 1670-1676. PMID: 31072745, DOI: 10.1016/j.arth.2019.04.012.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAgedAged, 80 and overAnemiaArthroplasty, Replacement, KneeDatabases, FactualDiabetes ComplicationsElective Surgical ProceduresFemaleHumansLength of StayMaleMiddle AgedPatient ReadmissionPlatelet CountPostoperative ComplicationsPostoperative PeriodPreoperative PeriodRetrospective StudiesThrombocytopeniaThrombocytosisTreatment OutcomeUnited StatesYoung AdultConceptsTotal knee arthroplastyElective total knee arthroplastyMinor adverse eventsPreoperative platelet countAbnormal platelet countLow platelet countPlatelet countHigher platelet countsAdverse eventsPostoperative complicationsTKA patientsAdverse outcomesKnee arthroplastyNational Surgical Quality Improvement Program databaseElective primary total knee arthroplastyMultivariate analysisQuality Improvement Program databasePrimary total knee arthroplastyMulticenter patient populationImprovement Program databasePostoperative adverse outcomesPlatelet count thresholdRetrospective comparative studyNormal platelet countLarger patient sample sizeChanges in Discharge to Rehabilitation: Potential Unintended Consequences of Medicare Total Hip Arthroplasty/Total Knee Arthroplasty Bundled Payments, Should They Be Implemented on a Nationwide Scale?
Zogg CK, Falvey JR, Dimick JB, Haider AH, Davis KA, Grauer JN. Changes in Discharge to Rehabilitation: Potential Unintended Consequences of Medicare Total Hip Arthroplasty/Total Knee Arthroplasty Bundled Payments, Should They Be Implemented on a Nationwide Scale? The Journal Of Arthroplasty 2019, 34: 1058-1065.e4. PMID: 30878508, PMCID: PMC6884960, DOI: 10.1016/j.arth.2019.01.068.Peer-Reviewed Original ResearchMeSH KeywordsAgedArthroplasty, Replacement, HipArthroplasty, Replacement, KneeComputer SimulationDecision TreesElective Surgical ProceduresHumansMedicareMiddle AgedMonte Carlo MethodPatient DischargePatient Protection and Affordable Care ActPatient ReadmissionQuality of LifeRehabilitationReimbursement MechanismsSkilled Nursing FacilitiesUnited StatesConceptsExtent of therapyHealth-related qualityType of rehabilitationFunctional recoveryPatients' health-related qualitySkilled nursing facility useElective total hipPrimary TKA patientsOutcomes of patientsPatient-centered outcomesPatients' functional recoveryInpatient rehabilitation facilityNursing facility useEpisode of careAverage functional outcomeBundled payment programsDischarge dispositionTKA patientsUnplanned readmissionTotal hipFunctional outcomeAffordable Care ActOutcome measuresRehabilitation facilityBundled PaymentsElective Total Shoulder Arthroplasty in Octogenarians: A Safe Procedure.
Bovonratwet P, Malpani R, Ondeck NT, Tyagi V, Grauer JN. Elective Total Shoulder Arthroplasty in Octogenarians: A Safe Procedure. Journal Of The American Academy Of Orthopaedic Surgeons 2019, 27: 145-154. PMID: 30252789, DOI: 10.5435/jaaos-d-17-00364.Peer-Reviewed Original ResearchConceptsPrimary total shoulder arthroplastyTotal shoulder arthroplastyNational Surgical Quality Improvement Program databaseQuality Improvement Program databaseImprovement Program databasePerioperative complicationsHospital stayProgram databaseShoulder arthroplastyElective total shoulder arthroplastyPropensity score-matched comparisonYoung populationRate of readmissionUrinary tract infectionPost-discharge careOctogenarian patientsPreoperative optimizationOctogenarian populationPerioperative coursePatient characteristicsTract infectionsSafe procedureRisk factorsOctogenariansReadmission
2018
Dialysis is an independent risk factor for perioperative adverse events, readmission, reoperation, and mortality for patients undergoing elective spine surgery
Ottesen TD, McLynn RP, Zogg CK, Shultz BN, Ondeck NT, Bovonratwet P, Bellamkonda KS, Rubin LE, Grauer JN. Dialysis is an independent risk factor for perioperative adverse events, readmission, reoperation, and mortality for patients undergoing elective spine surgery. The Spine Journal 2018, 18: 2033-2042. PMID: 30077772, DOI: 10.1016/j.spinee.2018.04.007.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedElective Surgical ProceduresFemaleHumansMaleMiddle AgedPatient DischargePatient ReadmissionPostoperative ComplicationsRenal DialysisReoperationSpineConceptsElective spine surgeryNon-dialysis patientsDialysis-dependent patientsPerioperative adverse eventsAdverse eventsDialysis patientsSpine surgeryUnplanned readmissionCohort studyPatient demographicsRisk factorsNational Surgical Quality Improvement Program databaseRisk-adjusted multivariate regressionsQuality Improvement Program databaseOperating roomDialysis-independent patientsInstitutional cohort studyMinor adverse eventsRetrospective cohort studyElective spinal surgeryImprovement Program databaseIndependent risk factorMajor adverse eventsPercentage of complicationsAdministrative database studyDialysis Patients Undergoing Total Knee Arthroplasty Have Significantly Increased Odds of Perioperative Adverse Events Independent of Demographic and Comorbidity Factors
Ottesen TD, Zogg CK, Haynes MS, Malpani R, Bellamkonda KS, Grauer JN. Dialysis Patients Undergoing Total Knee Arthroplasty Have Significantly Increased Odds of Perioperative Adverse Events Independent of Demographic and Comorbidity Factors. The Journal Of Arthroplasty 2018, 33: 2827-2834. PMID: 29754981, DOI: 10.1016/j.arth.2018.04.012.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedAged, 80 and overArthroplasty, Replacement, KneeComorbidityElective Surgical ProceduresFemaleHumansInpatientsLogistic ModelsMaleMiddle AgedMultivariate AnalysisOdds RatioPatient DischargePatient ReadmissionPostoperative ComplicationsQuality ImprovementRegression AnalysisRenal DialysisReoperationRetrospective StudiesRisk AssessmentConceptsTotal knee arthroplastyDialysis-dependent patientsAdverse eventsPatient demographicsDialysis patientsAdverse outcomesKnee arthroplastyNational Surgical Quality Improvement Program databaseOverall healthRisk-adjusted logistic regressionElective total knee arthroplastyQuality Improvement Program databaseImprovement Program databaseMinor adverse eventsNational inpatient databaseSevere adverse eventsBone health statusNondialysis cohortNondialysis patientsPerioperative periodTKA patientsAdult patientsPreoperative riskComorbidity factorsInstitutional cohortEvaluating the effect of growing patient numbers and changing data elements in the National Surgical Quality Improvement Program (NSQIP) database over the years: a study of posterior lumbar fusion outcomes
Shultz BN, Bovonratwet P, Ondeck NT, Ottesen TD, McLynn RP, Grauer JN. Evaluating the effect of growing patient numbers and changing data elements in the National Surgical Quality Improvement Program (NSQIP) database over the years: a study of posterior lumbar fusion outcomes. The Spine Journal 2018, 18: 1982-1988. PMID: 29649610, DOI: 10.1016/j.spinee.2018.03.016.Peer-Reviewed Original ResearchMeSH KeywordsData CollectionDatabases, FactualElective Surgical ProceduresHumansLumbosacral RegionPostoperative ComplicationsQuality ImprovementConceptsNational Surgical Quality Improvement ProgramNSQIP databaseERA groupPreoperative characteristicsPostoperative outcomesBlood transfusionSeptic shockOutcome studiesNational Surgical Quality Improvement Program databaseSurgeons National Surgical Quality Improvement ProgramQuality Improvement Program databaseSurgical Quality Improvement ProgramPosterior lumbar fusion surgeryLumbar fusion outcomesRetrospective cohort studyImprovement Program databaseYear of surgeryDeep vein thrombosisUrinary tract infectionLumbar fusion surgeryPostoperative day 30Number of patientsMultivariate Poisson regressionQuality Improvement ProgramPerioperative outcomesInaccuracies in ICD Coding for Obesity Would Be Expected to Bias Administrative Database Spine Studies Toward Overestimating the Impact of Obesity on Perioperative Adverse Outcomes
McLynn RP, Geddes BJ, Cui JJ, Ondeck NT, Bovonratwet P, Shultz BN, Grauer JN. Inaccuracies in ICD Coding for Obesity Would Be Expected to Bias Administrative Database Spine Studies Toward Overestimating the Impact of Obesity on Perioperative Adverse Outcomes. Spine 2018, 43: 526-532. PMID: 28767639, DOI: 10.1097/brs.0000000000002356.Peer-Reviewed Original ResearchConceptsBody mass indexMajor adverse eventsAdverse eventsICD codesVenous thromboembolismElective posterior lumbar fusionGreater body mass indexPerioperative adverse outcomesPostoperative adverse eventsRetrospective cohort studyAssociation of obesityImpact of obesityLength of stayPosterior lumbar fusionLarge academic hospitalSpine surgery literaturePostoperative complicationsPostoperative factorsCohort studyMass indexAdverse outcomesLumbar fusionAcademic hospitalBACKGROUND DATASpine studies
2017
Outpatient elective posterior lumbar fusions appear to be safely considered for appropriately selected patients
Bovonratwet P, Ottesen TD, Gala RJ, Rubio DR, Ondeck NT, McLynn RP, Grauer JN. Outpatient elective posterior lumbar fusions appear to be safely considered for appropriately selected patients. The Spine Journal 2017, 18: 1188-1196. PMID: 29155341, DOI: 10.1016/j.spinee.2017.11.011.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAgedAmbulatory Surgical ProceduresBlood TransfusionCohort StudiesDatabases, FactualElective Surgical ProceduresFemaleHumansInpatientsLumbar VertebraeMaleMiddle AgedPatient ReadmissionPatient SelectionPostoperative ComplicationsPropensity ScoreQuality ImprovementRetrospective StudiesSpinal FusionYoung AdultConceptsPosterior lumbar fusionPerioperative complicationsPostoperative complicationsNSQIP databaseInterbody fusionLumbar fusionNational Surgical Quality Improvement Program databaseSurgeons National Surgical Quality Improvement Program databaseElective posterior lumbar fusionQuality Improvement Program databasePropensity score-matched comparisonLower blood transfusionMost perioperative complicationsPostoperative adverse eventsRetrospective cohort comparison studyImprovement Program databaseRate of readmissionCareful patient selectionCohort comparison studyPotential confounding factorsInpatient cohortPLF casesHospital lengthPerioperative courseSelect patientsThe Rothman Index as a predictor of postdischarge adverse events after elective spine surgery
McLynn RP, Ondeck NT, Cui JJ, Swanson DR, Shultz BN, Bovonratwet P, Grauer JN. The Rothman Index as a predictor of postdischarge adverse events after elective spine surgery. The Spine Journal 2017, 18: 1149-1156. PMID: 29155251, DOI: 10.1016/j.spinee.2017.11.008.Peer-Reviewed Original ResearchMeSH KeywordsAgedElective Surgical ProceduresFemaleHumansMaleMiddle AgedPatient DischargePatient ReadmissionPostoperative ComplicationsSpineConceptsElective spine surgeryPostdischarge adverse eventsMinor adverse eventsMajor adverse eventsAdverse eventsRothman IndexSpine surgeryMedical CenterOverall patient conditionRothman Index scoresHigh-risk patientsRate of readmissionRetrospective cohort studyLarge academic medical centerPostoperative day 30Body mass indexLength of stayAcademic medical centerPresent studyElectronic medical recordsLater scoresAnesthesiologists classHospital lengthPerioperative outcomesCohort studyRisk factors and pharmacologic prophylaxis for venous thromboembolism in elective spine surgery
McLynn RP, Diaz-Collado PJ, Ottesen TD, Ondeck NT, Cui JJ, Bovonratwet P, Shultz BN, Grauer JN. Risk factors and pharmacologic prophylaxis for venous thromboembolism in elective spine surgery. The Spine Journal 2017, 18: 970-978. PMID: 29056565, DOI: 10.1016/j.spinee.2017.10.013.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedElective Surgical ProceduresFemaleFibrinolytic AgentsHeparinHumansMaleMiddle AgedNeurosurgical ProceduresPostoperative ComplicationsSpineVenous ThromboembolismConceptsElective spine surgeryPrior venous thromboembolismPharmacologic prophylaxisVenous thromboembolismAssociation of patientSpine surgeryRisk factorsUnfractionated heparinVTE prophylaxisInstitutional cohortNational Surgical Quality Improvement Program databaseElective spine surgery patientsRate of VTEQuality Improvement Program databaseDependent functional statusPerioperative blood transfusionRetrospective cohort studySpine surgery patientsImprovement Program databaseIndependent risk factorRetrospective cohort analysisIncidence of hematomaLonger operative timeLumbar spine surgerySingle-institution cohortDiscriminative ability of commonly used indices to predict adverse outcomes after poster lumbar fusion: a comparison of demographics, ASA, the modified Charlson Comorbidity Index, and the modified Frailty Index
Ondeck NT, Bohl DD, Bovonratwet P, McLynn RP, Cui JJ, Shultz BN, Lukasiewicz AM, Grauer JN. Discriminative ability of commonly used indices to predict adverse outcomes after poster lumbar fusion: a comparison of demographics, ASA, the modified Charlson Comorbidity Index, and the modified Frailty Index. The Spine Journal 2017, 18: 44-52. PMID: 28578164, DOI: 10.1016/j.spinee.2017.05.028.Peer-Reviewed Original ResearchConceptsPosterior lumbar fusionPerioperative adverse outcomesNational Surgical Quality Improvement ProgramCharlson Comorbidity IndexComorbidity indexAdverse outcomesAdverse eventsFrailty indexLumbar fusionSurgeons National Surgical Quality Improvement ProgramElective posterior lumbar fusionAnesthesiologists Physical Status Classification SystemDiscriminative abilitySurgical Quality Improvement ProgramPhysical Status Classification SystemAdverse outcome variablesDemographic factorsInfectious adverse eventsOutcome variablesPatient comorbidity indexPredictive demographic factorsMinor adverse eventsSevere adverse eventsBody mass indexHigh-level care
2016
Most 30-day Readmissions After Anterior Cervical Discectomy and Fusion Are Not Due to Surgical Site-Related Issues
Samuel AM, Fu MC, Toy JO, Lukasiewicz AM, Webb ML, Bohl DD, Basques BA, Albert TJ, Grauer JN. Most 30-day Readmissions After Anterior Cervical Discectomy and Fusion Are Not Due to Surgical Site-Related Issues. Spine 2016, 41: 1801-1807. PMID: 27398892, DOI: 10.1097/brs.0000000000001775.Peer-Reviewed Original ResearchConceptsAnterior cervical discectomyCommon reasonElective ACDFCervical discectomyNational Surgical Quality Improvement Program databaseQuality Improvement Program databaseAdequate postoperative managementHemorrhage/hematomaPreoperative medical optimizationCauses of readmissionCervical spine pathologyDays of dischargeHigher American SocietyImprovement Program databaseSurgical site infectionCareful patient selectionQuality-based reimbursementAnesthesiologists classMedical optimizationMost readmissionsNSQIP databasePostoperative daySite infectionPatient selectionPostoperative managementFactors Affecting Length of Stay and Complications After Elective Anterior Cervical Discectomy and Fusion
Gruskay JA, Fu M, Basques BA, Bohl DD, Buerba RA, Webb ML, Grauer JN. Factors Affecting Length of Stay and Complications After Elective Anterior Cervical Discectomy and Fusion. Clinical Spine Surgery A Spine Publication 2016, 29: e34-e42. PMID: 24525748, DOI: 10.1097/bsd.0000000000000080.Peer-Reviewed Original ResearchMeSH KeywordsAge FactorsAgedCervical VertebraeDatabases, FactualDecompression, SurgicalElective Surgical ProceduresFemaleHumansIntervertebral Disc DisplacementLength of StayMaleOrthopedicsOutcome Assessment, Health CarePostoperative ComplicationsRetrospective StudiesSeverity of Illness IndexSex FactorsUnited StatesConceptsLength of stayElective anterior cervical discectomyExtended LOSAnterior cervical discectomyAge 65 yearsMajor complicationsExtended surgery timeMultivariate analysisPreoperative anemiaPreoperative factorsCervical discectomySurgery timeNational Surgical Quality Improvement Project databaseSurgeons National Surgical Quality Improvement Project databaseAverage LOSOrgan space infectionVenous thrombotic eventsACS-NSQIP databaseFactors Affecting LengthLarge database analysisACDF proceduresASA scorePerioperative factorsPerioperative variablesPostoperative complications
2014
Complication Rates Following Elective Lumbar Fusion in Patients With Diabetes
Golinvaux NS, Varthi AG, Bohl DD, Basques BA, Grauer JN. Complication Rates Following Elective Lumbar Fusion in Patients With Diabetes. Spine 2014, 39: 1809-1816. PMID: 25010098, DOI: 10.1097/brs.0000000000000506.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAgedChi-Square DistributionDatabases, FactualDiabetes Mellitus, Type 1Diabetes Mellitus, Type 2Elective Surgical ProceduresFemaleHumansHypoglycemic AgentsInsulinLength of StayLogistic ModelsLumbar VertebraeMaleMiddle AgedMultivariate AnalysisOdds RatioPatient ReadmissionPostoperative ComplicationsRetrospective StudiesRisk FactorsSpinal FusionTime FactorsTreatment OutcomeUnited StatesYoung AdultConceptsInsulin-dependent diabetes mellitusLumbar fusion surgeryDiabetes mellitusPostoperative complicationsFusion surgeryLumbar fusionSurgeons National Surgical Quality Improvement Program databaseNational Surgical Quality Improvement Program databaseElective lumbar fusion surgeryQuality Improvement Program databaseEffects of NIDDMVentilator-assisted respirationWound-related infectionsAdverse postoperative outcomesRetrospective cohort studyImprovement Program databaseUrinary tract infectionDependent diabetes mellitusElective lumbar fusionPreoperative risk stratificationRisk of deathCommon chronic diseasesLength of stayCounseling of patientsUnplanned intubation