Gender is an essential determinant of blood transfusion in patients undergoing coronary artery bypass graft procedure.

STUDY OBJECTIVE: To determine factors that account for gender difference in the need for blood transfusion in coronary artery bypass graft (CABG) patients. DESIGN: Retrospective study of consecutive patients. SETTING: Anesthesiology department of a teaching hospital. PATIENTS: 253 CABG patients (163 males and 90 females). INTERVENTIONS: Packed red blood cells (PRBCs), platelets, and fresh frozen plasma (FFP) were transfused depending on the need of each patient. MEASUREMENTS AND MAIN RESULTS: For each patient, we recorded the gender, age, weight, height, body surface area (BSA), and duration of surgery. Hematocrit (Hct) levels prior to surgery, end of surgery, and at discharge from the hospital were recorded. PRBC administration and use of FFP and platelets were noted. Differences between the data for female and male patients were evaluated using Student's t-test, Chi-square test, and regression analysis. Approximately 60% female and only 20% male patients received PRBCs intraoperatively, whereas 78% females and only 43% males received PRBCs during their entire hospital stay. On average, females received 1.20 units of PRBCs intraoperatively and 2.38 units during the entire hospital stay, while the males received 0.31 units and 1.36 units for similar periods. Gender differences in PRBC transfusion persisted even when females and males were compared within the same subgroups for age, weight, duration of surgery, and preoperative Hct. PRBC units given intraoperatively had a significant correlation with age and preoperative Hct in females, but they had a significant correlation with age, preoperative Hct, and duration of surgery in males. PRBCs given during the entire hospital stay, however, had significant correlation with age, preoperative Hct, and duration of surgery in both females and males. Multiple logistic regression analysis showed that the probability of a patient receiving or not receiving PRBC transfusion is significantly influenced by age, preoperative PRBC mass, duration of surgery, and gender. CONCLUSION: Gender is an independent essential determinant of blood transfusion in CABG patients, and it may interact with age, weight, preoperative Hct, duration of surgery, and other factors in determining the probability of transfusion.

Acupressure treatment for prevention of postoperative nausea and vomiting.

Postoperative nausea and vomiting are still common problems after general anesthesia, especially in ambulatory surgery. Drug therapy is often complicated with central nervous system symptoms. We studied a nonpharmacological method of therapy--acupressure--at the Pericardium 6 (P.6) (Nei-Guan) meridian point. Two hundred consecutive healthy patients undergoing a variety of short surgical procedures were included in a randomized, double-blind study: 108 patients were in the acupressure group (Group 1) and 92 patients were in the control group (Group 2). Spherical beads of acupressure bands were placed at the P.6 points in the anterior surface of both forearms in Group 1 patients, while in Group 2 they were placed inappropriately on the posterior surface. The acupressure bands were placed before induction of anesthesia and were removed 6 h postoperatively. They were covered with a soft cotton wrapping to conceal them from the blinded observer who evaluated the patients for presence of nausea and vomiting and checked the order sheet for any antiemetics prescribed. In both groups, the age, gender, height, weight, and type and duration of surgical procedures were all comparable without significant statistical difference. In Group 1, only 25 of 108 patients (23%) had nausea and vomiting as compared to Group 2, in which 38 of 92 patients (41%) had nausea and vomiting (P = 0.0058). We concluded that acupressure at the P.6 (Nei-Guan) point is an effective prophylaxis for postsurgical nausea and vomiting and therefore a good alternative to conventional antiemetic treatment.

Local anesthesia is superior to spinal anesthesia for anorectal surgical procedures.

In this prospective study we compared local with spinal anesthesia for anorectal surgical procedures with regard to pain control, recovery time before unassisted ambulation, incidence of postoperative complications, length of hospital stay, and cost effectiveness in 80 consecutive patients. Patients were allocated in two groups: group 1 (n = 52) received local anesthesia, and group 2 (n = 28) had spinal anesthesia. There were no intraoperative complications related to the anesthetic technique, and there was no difference between groups in the number of doses of narcotics required to control postoperative pain (1.2 +/- 1.5 vs 1.8 +/- 1.7 in group 1 and 2 respectively, P > 0.05). Recovery time before unassisted ambulation was significantly longer in group 2 (139 +/- 96 minutes in group 2 vs 82 +/- 62 minutes in group 1, P < 0.05). There were 21/52 complications in group 1 in contrast to 21/28 in group 2, (P < 0.05). There was no difference between groups in the postoperative incidence of nausea, vomiting, headache, weakness, and constipation; however, the incidence of postoperative urinary retention was significantly higher in group 2 (5/52 in group 1 vs 9/28 in group 2, P < 0.05). As a result of urinary retention, more patients in group 2 required overnight hospitalization (12/52 in group 1 vs 21/28 in group 2, P < 0.05). Patients in group 2 required 36 hospital days in contrast to 21 days for patients in group 1, P < 0.05. The difference in hospital days resulted in $18,000 greater cost for patients in group 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Decreasing the risk of pulmonary artery rupture with a pressure relief balloon.

A pressure relief balloon has been recommended as one way to decrease catheter-related pulmonary artery rupture (PAR). There are approximately 1 to 2 PARs per 1,000 pulmonary artery catheter (PAC) insertions, resulting in significant morbidity and mortality. A new pressure relief balloon (PRB) introduced by Biosensors International (Singapore) was studied for its efficacy in increasing safety during PAC flotation balloon (FB) inflations. Ten human placentae were used for the experiment. The Biosensors PACs and the commonly used Baxter-Edwards (Irvine, CA) catheters were placed in placental veins and their FBs were gradually inflated with a maximum of 1.5 mL of air. Data revealed that PRBs consistently inflated when resistance was met by FBs and inflation pressure reached 1,000 mmHg. When PRBs were removed, the FBs inflated asymmetrically and distended beyond the catheter lumen or protruded through the vessel wall, causing bleeding upon deflation. Without the PRB, pressures reached up to 1,700 mmHg. In addition, the PRB gave visual evidence of resistance to the FB. In conclusion, the PRB is a safety device that limits overinflation of the distal PAC balloon, thus preventing vessel rupture. The device deserves serious consideration and outcome analysis.

Headache prevention following accidental dural puncture in obstetric patients.

STUDY OBJECTIVE: To evaluate the efficacy of a prophylactic saline patch and a prophylactic blood patch in prevention of headache following accidental dural puncture in obstetric patients. DESIGN: Prospective, randomized, single-blind study on dural puncture headache occurrence and cessation. SETTING: Inpatient obstetric unit at a metropolitan medical center. PATIENTS: Seventy-four inpatients who underwent vaginal delivery or cesarean section following accidental dural puncture during administration of epidural anesthesia for labor and delivery. INTERVENTIONS: Group 1 (n = 24), the control group, received fluids and analgesics. Group 2 (n = 30) received prophylactic epidural saline (40 to 60 ml) through the epidural catheter following completion of the obstetric procedure. Group 3 (n = 20) received autologous blood (15 ml) via epidural catheter following completion of the obstetric procedure. MEASUREMENTS AND MAIN RESULTS: In Group 1, 21 of 24 patients (87.5%) developed headaches, with conservative management. In Group 2, 20 of 30 patients (66.7%) developed headaches, and in Group 3, 1 of 20 patients (5%) developed a headache. CONCLUSIONS: The results of this study suggest that the administration of a prophylactic epidural blood patch is highly effective in the prevention of headaches following dural puncture, with headache frequency reduced from 87.5% to 5%.

A survey of 800 patients' knowledge, attitudes, and concerns regarding anesthesia.

The present study was undertaken to assess patients' knowledge, attitudes, and concerns regarding anesthetic management. A survey of 34 items was developed and administered preoperatively to 800 consecutive patients. Included were 303 men and 497 women with a mean age 52 yr and a mean educational level of 12 yr. Patients were interviewed on their knowledge of the role and training of anesthesiologists and on their preferences regarding anesthetic management. Patients also rated the intensity of their concern on 20 written statements expressing potential anesthetic complications. Results indicated that patients' perceptions of the anesthesiologist's training and role were accurate. Most patients preferred (a) general to regional anesthesia and (b) not to select their own anesthesiologist. Most significant preoperative concerns regarding the anesthesiologist focused on experience, qualifications, and presence or absence during the anesthesia. Patient concerns also included the possibility of not waking up postoperatively, experiencing pain, and becoming paralyzed. Intensity of concern was inversely related to age and unrelated to educational level or occupation. Variables related to type of concern included patient's sex, type of anesthesia, and proposed surgical procedure. Issues of least concern included disclosure of personal matters during anesthesia, experiencing impaired judgment postoperatively, and being asleep or bedridden for a prolonged period of time. It is suggested that anesthesiologists address significant patient concerns during the preoperative visit to enhance their effectiveness in patient care. Efforts to educate the public on the anesthesiologist's role in perioperative care should improve patient confidence.

Effects of clear liquids on gastric volume and pH in healthy volunteers.

The effects of clear liquids on gastric volume and pH were examined in 30 healthy ASA physical status I volunteers. After overnight fasting, a Salem-sump nasogastric tube was inserted and gastric contents were removed for measurement of volume and pH. Gastric contents were then reinserted through the nasogastric tube into the stomach. The volunteers were randomly divided into three groups: group 1 (n = 10) received 240 mL water, group 2 (n = 10) received 240 mL coffee, and group 3 (n = 10) received 240 mL pulp-free orange juice. All liquids were administered orally. Gastric contents were then again aspirated, measured for volume and pH, and reinserted through the nasogastric tube every half hour until gastric volume was less than 25 mL. All volunteers had gastric volumes less than 25 mL with a slight decrease in pH within 2 h of orally taking one of the three 240-mL liquids. These data suggest that if patients have ingested a moderate amount of clear liquids it is safe to conduct general anesthesia after a 2-h fast in healthy surgical patients.

Comparison of intrathecal meperidine and lidocaine in endoscopic urological procedures.

The purpose of this study was to determine if a small dose of intrathecal meperidine would achieve adequate spinal anaesthesia while minimizing complications and to compare its effectiveness with lidocaine. The spinal anaesthetic effects of five per cent lidocaine 0.5 mg.kg-1 in 7.5 percent glucose (n = 20) or five per cent meperidine 0.5 mg.kg-1 (n = 22) were evaluated in 42 ASA physical status II or III patients. Intrathecal injection of the anaesthetic agent was given with the patient in the sitting position in which he remained for ten minutes before being placed in the lithotomy position. The onset time for sensory blockade was seven minutes in the lidocaine group and ten minutes in the meperidine group. Final sensory levels were identical in both groups. Mean arterial blood pressure decreased significantly in the lidocaine group but not in the meperidine group. Motor block was absent in ten patients in the meperidine group but was present in all the patients in the lidocaine group. Duration of postoperative analgesia was 968 min in the meperidine group and 681 min in the lidocaine group (NS). Complications such as nausea, vomiting, itching, drowsiness and respiratory depression were similar in the two groups. It is concluded that low-dose meperidine, 0.5 mg.kg-1, is effective as a spinal anaesthetic agent and has few complications.

Interpleural block: a new technique for regional anaesthesia during percutaneous nephrostomy and nephrolithotomy.

Interpleural block was used in four patients undergoing percutaneous nephrostomy, one of whom also underwent percutaneous nephrolithotomy. Interpleural block was achieved with the standard technique using 30 ml of 0.5 per cent bupivacaine. All patients tolerated the procedure well and remained haemodynamically stable during the operative procedure. Mean pain relief from initiation of interpleural block was ten hours (SD = 4.32). Interpleural block was an effective method of obtaining anaesthesia for percutaneous nephrostomy and nephrolithotomy in these four patients.

Pleural block: technique for regional anesthesia during percutaneous hepatobiliary drainage.

A new technique was used to achieve safe regional anesthesia in seven patients undergoing percutaneous hepatobiliary drainage. The pleural block was administered, and pain was assessed during and after the procedure by means of sensitivity to pin prick, verbal response, electrocardiographic tracings, and blood pressure measurements. In all patients the technique produced relief of somatic pain and did not alter hemodynamic or respiratory status.

The effect of internal mammary artery grafting on the perioperative course.

Internal mammary artery (IMA) grafts are being used for myocardial revascularization with increasing frequency because of a higher 10-year patency rate and actuarial survival rate as compared to saphenous vein grafts. This study sought to evaluate whether IMA grafts are associated with an increased usage of blood and blood products, operating time, postoperative hospital stay, or incidence of reoperation due to bleeding. A total of 189 consecutive patients undergoing aortocoronary bypass procedures (group I, N = 59, with no IMA grafts; group II, N = 108, with single IMAs; and group III, N = 22, with double IMAs) were studied over 6 months. Significant differences were seen in their age (group I, 71.6 years; group II, 62.1 years; and group III, 57.1 years); cross-clamp time (62 minutes for group I, 65 minutes for group II, and 83.7 minutes for group III); and duration of operation (400 minutes for group I, 423 minutes for group II, and 501 minutes for group III). Use of blood products including packed red blood cells, fresh frozen plasma, and platelets during the operation and postoperatively was similar in all three groups. The duration of postoperative hospital stay was statistically similar for each group, being 16.6 days for group I, 13.1 days for group II, and 13.7 days for group III. The number of vessels grafted was statistically similar for groups I and II (3.1 and 3.3 vessels, respectively), but group III had a statistically larger number of vessels grafted (3.7 vessels). The reoperation rate for bleeding was similar for all three groups.(ABSTRACT TRUNCATED AT 250 WORDS)