NMS. Casos Clínicos

13

Chapter 1 ♦ Preoperative Care

Table 1-6: Pulmonary Function Values Suggesting Increased Perioperative Risk of Pulmonary Complications* Test Value Significance FEV 1 Moderate risk (major surgery) High risk (major surgery) Pulmonary wedge resection only can be tolerated. <70% of predicted <35% of predicted 0.6 L

Major pulmonary resection up to a pulmonary lobectomy can be tolerated. Major pulmonary resection up to a pneumonectomy can be tolerated.

1 L

2 L

FVC PAP

<50%–75% of predicted Moderate risk

>25 mm Hg

Moderate to high risk

Arterial blood Paco 2 >45 mm Hg Moderate risk *Pulmonary risk includes postoperative atelectasis, pneumonia, pneumothorax, inability to wean patient from ventilator, right heart failure, and death. FEV 1 , forced expiratory volume in 1 sec; FVC, forced vital capacity; PAP, pulmonary arterial pressure.

Digging Deep

The choice of operation may also substan- tially influence the postoperative course. For example, open cholecystectomy is one op- tion, which may be prudent in this case be- cause of the risk of CO 2 absorption into the

blood with laparoscopic cholecystectomy. Cholecystostomy is another option. Under local anesthesia, a tube is placed in the gallbladder either under radio- logic guidance or via a small incision made in the abdomen. Drainage to the ex- terior usually resolves the acute sepsis, avoiding the need for cholecystectomy at this time. These examples demonstrate that a high-risk patient’s condition influences the choice of surgical procedure. If cholecystostomy is chosen, you are choosing a less definitive procedure. It locally manages the sepsis associ- ated with acute cholecystitis but does not remove the source—the diseased gallbladder—which may need removal at a later date and certainly when the patient is in a lower risk condition. Laparoscopy may lead to increased CO 2 absorption into the blood, which then requires excretion through the lungs and increased pulmonary work. This further compromises a patient’s pulmonary status and would be contraindicated in this patient. SAMPLE