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Postoperative Care


Paul K. Mohabir

, MD, Stanford University School of Medicine;

André V Coombs

, MBBS, Texas Tech University Health Sciences Center

Last full review/revision Nov 2020| Content last modified Nov 2020
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Postoperative care begins at the end of the operation and continues in the recovery room and throughout the hospitalization and outpatient period. Critical immediate concerns are airway protection, pain control, mental status, and wound healing. Other important concerns are preventing urinary retention, constipation, deep venous thrombosis (DVT), and blood pressure variability (high or low). For patients with diabetes, blood glucose levels are monitored closely by fingerstick testing every 1 to 4 hours until patients are awake and eating, because better glycemic control improves outcomes.


Most patients are extubated before leaving the operating room and soon become able to clear secretions from their airway. Patients should not leave the recovery room until they can clear and protect their airway (unless they are going to an intensive care unit [ICU]). After intubation, patients with normal lungs and trachea may have a mild cough for 24 hours after extubation; for smokers and patients with a history of bronchitis, postextubation coughing lasts longer. Most patients who have been intubated, especially smokers and patients with a lung disorder, benefit from an incentive inspirometer.

Postoperative dyspnea may be caused by pain secondary to chest or abdominal incisions (nonhypoxic dyspnea) or by hypoxemia (hypoxic dyspnea—see also Oxygen Desaturation). Hypoxemia secondary to pulmonary dysfunction is usually accompanied by dyspnea, tachypnea, or both; however, oversedation may cause hypoxemia but can blunt dyspnea, tachypnea, or both. Thus, sedated patients should be monitored with pulse oximetry or capnometry. Hypoxic dyspnea may result from atelectasis or, especially in patients with a history of heart failure or chronic kidney disease, fluid overload. Whether dyspnea is hypoxic or nonhypoxic must be determined by pulse oximetry and sometimes arterial blood gas; chest x-ray can help differentiate fluid overload from atelectasis.

Hypoxic dyspnea is treated with oxygen. Nonhypoxic dyspnea may be treated with anxiolytics or analgesics.


Pain control may be necessary as soon as patients are conscious. Opioids are typically the first-line choice and can be given orally or parenterally. Often, oxycodone/acetaminophen 1 or 2 tablets (each tablet can contain 2.5 to 10 mg oxycodone and 325 to 650 mg acetaminophen) orally every 4 to 6 hours or morphine 2 to 4 mg IV every 3 hours is given as a starting dose, which is subsequently adjusted as needed; individual needs and tolerances can vary several-fold. With less frequent dosing, breakthrough pain, which should be avoided, is possible. For more severe pain, IV patient-controlled, on-demand dosing is best (see Dosing and Titration). If patients do not have a renal disorder or a history of gastrointestinal bleeding, giving nonsteroidal anti-inflammatory drugs (NSAIDs) at regular intervals may reduce breakthrough pain, allowing the opioid dosage to be reduced.

Mental status

All patients are briefly confused when they come out of anesthesia. Older patients, especially those with dementia, are at risk of postoperative delirium, which can delay discharge and increase risk of death. Risk of delirium is high when anticholinergics are used. These drugs are sometimes used before or during surgery to decrease upper airway secretions, but they should be avoided whenever possible. Opioids, given postoperatively, may also cause delirium, as can high doses of H2 blockers. The mental status of older patients should be assessed frequently during the postoperative period. If delirium occurs, oxygenation should be assessed, and all nonessential drugs should be stopped. Patients should be mobilized as they are able, and any electrolyte or fluid imbalances should be corrected.

Wound care

The surgeon must individualize care of each wound, but the sterile dressing placed in the operating room is generally left intact for 24 to 48 hours unless signs of infection (eg, increasing pain, erythema, drainage) develop. After the operative dressing is removed, the site should be checked twice daily for signs of infection. If they occur, wound exploration and drainage of abscesses, systemic antibiotics, or both may be required. Topical antibiotics are usually not helpful. A drain tube, if present, must be monitored for quantity and quality of the fluid collected. However, drain tubes should be removed as soon as possible, because they can serve as a nidus for infection and may not manifest signs of adverse effects such as bleeding or anastomotic leak. Sutures, skin staples, and other closures are usually left in place 7 days or longer depending on the site and the patient. Face and neck wounds may be superficially healed in 3 days; wounds on the lower extremities may take weeks to heal to a similar degree.

Deep venous thrombosis (DVT) prophylaxis

Risk of DVT after surgery is small, but because consequences can be severe and risk is still higher than that in the general population, prophylaxis is often warranted. Surgery itself increases coagulability and often requires prolonged immobility, which is another risk factor for DVT (see Pulmonary Embolism and Deep Venous Thrombosis). Prophylaxis for DVT usually begins in the operating room or earlier (see Table: Risk of Deep Venous Thrombosis and Pulmonary Embolism in Surgical Patients). Alternatively, heparin may be started shortly after surgery, when risk of bleeding has decreased. Patients should ambulate or undergo physical therapy to facilitate mobilization as soon as it is safe to do so.


A common cause of postoperative fever is an inflammatory or hypermetabolic response to an operation. Other causes include pneumonia, urinary tract infection (UTIs), wound infections, and deep venous thromboses (DVTs). Additional possibilities are drug-induced fever and infections affecting implantable devices and drains. Common causes of fever during the days or weeks after surgery include the so-called "six Ws":

  • Wound infections

  • Water (eg, UTIs)

  • Wind (eg, atelectasis, pneumonia)

  • Walking (eg, DVTs)

  • Wonder drugs (eg, drug-induced fever)

  • Widgets (eg, implantable devices, drains)

Optimal postoperative care (eg, early ambulation and removal of bladder catheters, meticulous wound and drain care) can decrease risk of DVTs, UTIs, and wound infections. Incentive spirometry and periodic coughing can help decrease risk of pneumonia and should be encouraged up to 10 times once every hour.

Urinary retention and constipation

Urinary retention and constipation are common after surgery. Causes include

  • Anticholinergics

  • Opioids

  • Immobility

  • Decreased oral intake

Urine output must be monitored. Straight catheterization is typically necessary for patients who have a distended bladder and are uncomfortable or who have not urinated for 6 to 8 hours after surgery; the Credé maneuver (application of suprapubic pressure during voiding) sometimes helps and may make catheterization unnecessary. Chronic retention is best treated by avoiding causative drugs and by having patients sit up as often as possible. Bethanechol 5 to 10 mg orally can be tried in patients unlikely to have any bladder obstruction and who have not had a laparotomy; doses can be repeated every hour up to a maximum of 50 mg/day. Sometimes an indwelling bladder catheter is needed, especially if patients have a history of retention or a large initial output after straight catheterization. However, an indwelling catheter should be removed as soon as possible to decrease the risk of infection.

Constipation is common and typically secondary to anesthetic drugs, bowel surgery, postoperative immobility, and opioids. Constipation is treated by minimizing use of opioids and other constipating drugs, by beginning postoperative ambulation early, and, if patients have not had gastrointestinal surgery, by giving stimulant laxatives (eg, bisacodyl, senna, cascara). Stool softeners (eg, docusate) do not alleviate postoperative constipation.

Loss of muscle mass (sarcopenia)

Loss of muscle mass (sarcopenia) and strength occur in all patients who require prolonged bed rest. With complete bed rest, young adults lose about 1% of muscle mass/day, but older patients lose up to 5%/day because growth hormone levels decrease with age. Avoiding sarcopenia is essential to recovery. Thus, patients should sit up in bed, transfer to a chair, stand, and exercise as much as and as soon as is safe for their surgical and medical condition. Nutritional deficiencies may also contribute to sarcopenia. Thus, nutritional intake of patients on complete bed rest should be optimized. Oral intake should be encouraged, and tube feeding or, rarely, parenteral feeding may be necessary.

Other issues

Certain types of surgery require additional precautions. For example, hip surgery requires that patients be moved and positioned so that the hip does not dislocate. Any physician moving such patients for any reason, including auscultating the lungs, must know the positioning protocol to avoid doing harm; often, a nurse is the best instructor.

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