The Effects of Obesity on the Cardiopulmonary System: Implications for Critical Care Nursing

Kim Garrett, RN, MS, CNP; Kathy Lauer, RN, PhD; Beth-Anne Christopher, RN, MS


Prog Cardiovasc Nurs. 2004;19(4) 

In This Article

Other Considerations for Nursing Care of the Obese Patient

Due to the alveolar collapse commonly associated with obesity, incentive spirometry and aggressive chest physiotherapy should be performed.[15] Because of reduced lung volumes and increased airway resistance associated with obesity, tidal volume calculations should be based on ideal body weight and then adjusted according to blood gases and inflation pressures. The addition of positive end-expiratory pressure may help prevent atelectasis and decrease ventilation-perfusion mismatching. Placing the patient in a reverse Trendelenberg's position at 45° results in increased tidal volumes and lower respiratory rates, facilitating weaning.[15,16] Individuals with a history of OHS or OSAS may benefit from the nocturnal use of bilevel-positive airway pressure.

Nursing actions to promote air exchange include: 1) avoiding supine, lithotomy, and Trendelenberg's positions; 2) assessing for clinical signs of hypoxia, including altered level of consciousness, arrhythmias, cyanosis or other changes in skin color, and changes in rate, depth, or quality of respirations; and 3) monitoring pulse oximetry and arterial blood gases. Try to position the patient with optimal respiratory function in mind. Place the pillows so as not to inhibit chest wall expansion; pillows placed behind the head should be small to prevent obstruction of the airway.[17] Lastly, pain control, such as continuous epidural patient-controlled analgesia, is recommended in the postoperative patient to minimize respiratory depression.[15]

Obese patients tend to produce large amounts of respiratory secretions and are at increased risk of aspiration.[17] Specialty beds with lateral rotation should be considered when the patient is admitted to the unit. These beds have been shown to help mobilize pulmonary secretions and maximize ventilation through all lung areas and must be initiated within the first 24 hours of hospitalization to be of benefit. Individual manufacturers should be contacted for specific protocols and weight restrictions related to their product. Diligent suctioning, frequent oral and pulmonary hygiene, and maintaining a 30º elevation will help prevent aspiration. In addition, placement of a nasogastric tube should be considered if abdominal distention is present. Feeding tubes should be checked for residual volume per hospital protocol.

Vascular access is also more difficult to obtain in the obeseindividual. Poor peripheralvenous access options lead to more frequent use of central venous catheters. Loss of landmarks, greater distance from skin to vessel, and short, stubby necks make placement of central lines more challenging and result in a higher incidence of malpositions and complications.[15,27] Similar difficulties may occur with the placement of arterial lines.

Absorption and distribution of medications may be impaired and lead to a subtherapeutic or toxic dose. Adjustments in typical dosages may be needed based on the patient's response to medications; alternate routes of administration may need consideration. Collaboration among registered nurses, physicians, and pharmacists is essential to optimize expected pharmacological outcomes.[28]

Poorly vascularized adipose tissue is at higher risk for wound dehiscence and infection. Support with pillows excess adipose tissue, which can weigh down or pull at suture lines. Prevention of friction, shearing, maceration, and pressure areas are the priority of skin care in the obese patient. Skin should be thoroughly assessed at every shift for signs of breakdown or infection. Therapies should be selected based on the patient's mobility and risk of skin breakdown and should be kept clean and dry with special attention to skin folds.[17,28]

Nutritionally, it is important to avoid extreme caloric restrictions. Catabolism-induced muscle loss will impair healing of surgical wounds. Moreover, it weakens diaphragmatic, intercostal, skeletal, and myocardial muscles, delays ventilator weaning, slows rehabilitation, and promotes complications. A moderate caloric restriction may enhance fat burning while sparing lean tissue.[28]

Performing cardiopulmonary resuscitation and emergency life support on an obese patient may be impeded by excess tissue mass. Difficulty in the correct placement and fitting of a face mask may lead to air leaks, as well as passage of air into the stomach, which can also occur because of the increased pressure needed to inflate the lungs. Excess neck tissue may obstruct the airway and make intubation more difficult. When performing chest compressions, placing the patient in reverse Trendelenberg's position during cardiopulmonary resuscitation may help decrease intra-abdominal pressure on the diaphragm.[17]

Awareness of weight limitations on equipment is necessary and may indicate the need for an alternative treatment or diagnostic testing. Advanced planning and obtaining the proper equipment will help in treating and caring for these patients. Many companies now specialize in providing specialty equipment, including beds, commodes, chairs, lifts, carts, and specially reinforced tables for procedures and diagnostic tests.[29]

Lastly, obese individuals often suffer from social stigmatization and discrimination. As patient advocates, it is important for nurses to examine their attitudes toward this population. It is the nurse's responsibility to foster acceptance and a nonjudgmental attitude from everyone who cares for, and comes in contact with, these patients. Promoting sensitivity, providing education about obesity, and not tolerating derogatory jokes or comments are important issues for nurses to consider in helping to develop a culture of acceptance for the obese patient.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.