Preoperative Assessment & Perioperative Care: DVT, Delirium & More


Developed by UNMC Department of Anesthesia and Division of Geriatrics, Department of Internal Medicine
Tyler Hartley M4

Upon completion of this module, the learner will be able to:

  • Describe DVT/PE prophylaxis strategies that are available, indications and medications used.
  • Describe when to use mechanical methods versus anticoagulants in surgical patients.
  • Describe deliriums influence on morbidity and mortality.
  • Describe the management of delirium through modification of risk factors.
  • Describe the effect of frailty on elderly surgical patient outcomes.

DVT Prophylaxis

Incidence and mortality of Deep Venous Thrombosis (DVT) and Pulmonary Embolism (PE) in surgical patients.
General Surgery Other Surgeries* All Surgeries
DVT 20-30% incidence ~ 40% incidence
Fatal PE 1-5%

Up to 38% of postoperative deaths from pulmonary causes are due to pulmonary emboli.
*Other surgeries refers to : Knee, hip, gynecologic cancer, open prostatectomies and major neurosurgical procedures.


  • Prevention begins with entry of the patient into the hospital and involves all admitting orders. At the very least post-operative orders should address this issue for dosage and type of therapy.
  • The most effective tool in prevention is DVT prophylaxis. This chart has been included on the pearl card to assist you in this management. The following paragraphs will explain the recommendations.
  • DVT prophylaxis is critical and has been around for years. This is a current review of the recommendations that I will walk you through.

Common Errors

DVT/PE Prophylaxis Strategies in Older Medical and Surgical Inpatients
DVT/PE Risk Surgery Type or Medical Condition Thromboprophylactic Options

Healthy and mobile patients undergoing minor surgery
Brief (<45 min) laparoscopic procedures
Transurethral or other low-risk urologic procedures
Joint arthroscopy
Spine Surgery

Aggressive early ambulation after procedure +/- intermittent pneumatic compression


Immobile (>72hr) patients
Inpatients at bed rest with active malignancy, prior VTE, or sepsis
Most general surgeries
Open abdominopelvic surgeries
Thoracic surgery
Vascular surgery

*Antithrombotic +/- intermittent pneumatic compression


Acute stroke
Hip or knee arthroplasty
Hip, pelvic, or leg fracture
Acute spinal cord injury

See table below

* Note: Antithrombotics refer to antiplatelet, VK antagonists, heparin, LMWH, heparinoid, Factor Xa inhibitors, Direct thrombin inhibitors.



Antithrombotic Medications for VTE Prophylaxis
Indication Antiplatelet VK Antagonist Heparin LMWH Heparinoid Factor Xa inhibitor Direct Thrombin Inhibitor
Medical inpatients at moderate-high risk or VTE; patients with acute stroke of spinal cord injury ----- ----- UFH* Enoxaparin*
----- Fondaparinux* -----
Knee or hip replacement ASA Warfarin* UFH Enoxaparin* Danaproid Fondaparinux
Hip fracture ASA Warfarin* UFH Dalteparin* Danaproid Fondaparinux
Nonorthopedic surgery patients at moderate-high risk of VTE ASA Warfarin* UFH Enoxaparin*

*Notes: First choice(s) in bold text; secondary or alternative choice(s) in regular text; LMWH = low-molecular weight heparin; UFH = unfractionated heparin; VK = vitamin K; VTE = venous thromboembolism (DVT/PE)



VK Antogonist
Patients on Chronic Warfarin (Coumadin) Therapy.

LDUH: low dose unfractionated heparin

LMWH: Low Molecular Weight Heparin


Factor Xa inhibitor

Direct Thrombin Inhibitor

Delirium Prevention




Procedure Incidence
General Sugery 16%
Orthopedic 28-61%
Total knee arthroplasty or hip surgery 61%
Opthalmologic: cataracts 1-3%
Urological surgery 26%
Neurosurgery 21.4%

Gani H, et el, The incidence of postoperative delirium in elderly patients after urologic surgery. 2013;67.

Steve M.M. de Castro, et el, Incidence and risk factors of delirium in the elderly general surgical patient, The American Journal of Surgery, Volume 208, Issue 1, July 2014, Pages 26-32

Pearl of Wisdom

Insomnia Induced Delirium


Frailty Criteria

Shrinking (weight loss)

>10 pound weight loss during previous year

Weakness (grip strength)

Lowest 20th percentile measured by hand-held dynamometer


Feeling "I can't get going" or "everything is an effort" 3 or more days per week

Activity level

Kilocalorie expenditure less than 20th percentile for gender

Walking speed

Lowest 20th percentile walking 15 feet at normal pace

Each criteria is scored with a 0 or a 1. Intermediately frail was defined by meeting 2-3 criteria, while frail patients were defined by meeting 4-5 frailty criteria.
Makary MA, Segev DL, Pronovost PJ, et al. Frailty as a predictor of surgical outcomes in older patients. J Am Coll Surg 2010; 210:901.


Frail patients (4-5 criteria) have a 2.54-times higher odds of complications when compared with nonfrail patients postoperatively.

  • DVTs are best managed prophylactically.
  • Always write orders for DVT prophylaxis on all elderly patients.
  • Delirium has many risk factors and therefore many treatment options.
  • Frailty can be measured and may be used as a predictor of surgical outcomes.