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Procedures before the discovery of anesthesia were necessarily of short duration. Raper relates that surgical cases lasting more than 20 minutes would usually result in the death of the patient, because the stress associated with such intense nociception would exhaust the patient's reserves. Highly stressful procedures such as abdominal surgery were rarely attempted before 1846. Ephraim McDowell[379] (1771–1830), a rural surgeon from Kentucky, performed the first successful intraperitoneal procedure when he excised a 10-kg ovarian cyst from Mrs. Jane Todd Crawford in 1809. McDowell's publication of the case achieved for him a small measure of fame, unusual for a rural practitioner. However, intraperitoneal procedures are among the most highly stressful operations, and McDowell's accomplishment was rarely repeated. The first successful upper abdominal procedure occurred only after the advent of general anesthesia. Theodor Billroth (1829–1894) performed the first gastrectomy with chloroform anesthesia on January 29, 1881.
The idea that reduction of perioperative stress had a beneficial effect on recovery was championed by George W. Crile (1864–1943), chief surgeon at the Cleveland Clinic at the beginning of the 20th century. Crile's operative technique was to infiltrate all tissues with dilute procaine before incision. Patients were lightly anesthetized with mask inhalation of nitrous oxide and oxygen.[380] He describes these concepts of stress-free anesthesia in his book, Anoci-Association, published in 1914.[381]
An early devotee of Crile's ideas was the prominent neurosurgeon Harvey Cushing[382] (1869–1939), who promoted the use of regional blocks before emergence from ether anesthesia to ensue a smooth postoperative course. Cushing was the first surgeon to use blood pressure measurements on his patients after he learned the Rovi-Rocci method in Italy ( Fig. 1-16 ). Accurate anesthetic records were maintained during Cushing's cases [257] and confirmed his opinion that shock could be prevented by careful attention to avoiding the stresses associated with surgery.
Figure 1-16
One of Harvey Cushing's early anesthesia records shows
systolic blood pressure (top tracing) and pulse rate
(bottom tracing). The first rise in blood pressure
occurred during the excitement phase of ether induction, and the second rise occurred
during the release of adhesions of the sciatic nerve. Vertical lines take place
2.5 minutes apart. The systolic blood pressure rose to greater than 230 mm Hg during
the operation. Cushing was an early proponent of regional anesthesia, possibly stemming
from his observations on blood pressure and heart rate.[382]
(From Cushing H: On routine determination of arterial tension in operating
room and clinic. Boston Med Surg J 148:250–256, 1903.)
Crile's ideas have had significant impact on how the modern anesthesiologist defines general anesthesia. In 1957, P. Woodbridge [383] defined general anesthesia as comprising four components: (1) sleep or unconsciousness, (2) blockade of undesirable reflexes, (3) motor blockade, and (4) sensory blockade. These ideas have been discussed and modified by M. Pinsker[384] into three components: (1) paralysis, (2) unconsciousness, and (3) attenuation of the stress response. Lundy's balanced anesthesia[310] is another formulation of the idea that several drugs can be used in combination to produce the state of unconsciousness and analgesia that we define as general anesthesia.
An enduring question during the past century, since Crile's introduction of the concept of stress-free anesthesia, has been how to evaluate the analgesic component of the ideal general anesthetic. Michael Roizen[385] observed in 1981 that general anesthetics did not prevent the increase in sympathetic activity in response to a skin incision, even in concentrations that prevented movement. Surgical stimulation often results in intraoperative hypertension and tachycardia, with the corollary that interventions that prevent these hemodynamic reflexes provide "analgesia." Hemodynamic instability was of marginal significance until surgeons began to operate on patients with significant ischemic heart disease. Studies have demonstrated that perioperative β-adrenergic blockade reduces the risk of perioperative myocardial infarction in patients at risk for this complication.[386]
It became apparent that intravenous opioids were highly successful in ablating the hemodynamic markers of stress. Edward Lowenstein[387] used large doses of morphine to stabilize heart rate and blood pressure during cardiac surgery. In 1967, the short-acting opioid fentanyl was introduced to provide intraoperative hemodynamic stability. Theodore H. Stanley[388] reported its successful use in large doses for cardiac surgery without the side effect of histamine release that sometimes occurs after morphine administration. Other short-acting opioids tailored for the anesthesiologist have been added since that time. Alfentanil, sufentanil, and remifentanil have different pharmacokinetic profiles that make them suitable agents for selected procedures. Naloxone, a specific antagonist for this class of drugs, was first used clinically in 1971.[389] An increased understanding of opioid pharmacology has opened up a new role for anesthesiologists, including acute pain management. Rapid detoxification of opioid addiction by using general anesthesia combined with opioid antagonism is a new technique that, if combined with judicious follow-up, can be a useful treatment for this condition.[390]
The combination of opioids with tranquilizers such as phenothiazines and butyrophenones provides a form of anesthesia called neuroleptanesthesia, which was introduced by DeCastro and Mundeleer[391] in 1959. Patients administered this form of anesthesia are immobile and are tranquil and have stable hemodynamics even during major surgical procedures. One goal of this technique is to block the autonomic and endocrine response to stress. This unique method of providing anesthesia is one other method of ablating the stress response, but unless other agents such as nitrous oxide or other intravenous agents are administered, there can be a high incidence of awareness. Side effects from dopamine antagonism such as dysphoria and uncontrolled extrapyramidal motor movements have limited the widespread use of neuroleptanesthesia.
During the past 30 years, several investigators began a series of studies to measure the markers of the stress response during and after surgery. It was learned that during major surgery, patients anesthetized with traditional vapor anesthetics with or without opioids displayed increased levels of catabolic hormones postoperatively.[99] Significant elevations were observed for the catecholamines and for adrenocorticotropic hormone, cortisol, antidiuretic hormone, and growth hormone. Various methods of preventing postoperative catabolism have been under investigation for several years. The resulting catabolic state is thought by some to delay recovery and, with some operations, can be prevented with the use of neuraxial block.[99] [392] [393] It is apparent from recent reviews on this subject that the formulations of George Crile are still valid 100 years after he promoted them and likely to be the subject of further studies in the future.
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