Tumescent technique for local anesthesia improves safety in large-volume liposuction

The tumescent technique for local anesthesia improves the safety of large-volume liposuction ( > or = 1500 ml of fat) by virtually eliminating surgical blood loss and by completely eliminating the risks of general anesthesia. Results of two prospective studies of large-volume liposuction using the tumescent technique are reported. In 112 patients, the mean lidocaine dosage was 33.3 mg/kg, the mean volume of aspirated material was 2657 ml, and the mean volume of supernatant fat was 1945 ml. The mean volume of whole blood aspirated by liposuction was 18.5 ml. For each 1000 ml of fat removed, 9.7 ml of whole blood was suctioned. In 31 large-volume liposuction patients treated in 1991, the mean difference between preoperative and 1-week postoperative hematocrits was -1.9 percent. The last 87 patients received no parenteral sedation. In a second study, a 75-kg woman received 35 mg/kg of lidocaine on two separate occasions, first without liposuction and 25 days later with liposuction; peak plasma lidocaine concentrations occurred at 14 and 11 hours after beginning the infiltration and were 2.37 and 1.86 micrograms/ml, respectively.     

The impact of liposuction on body fat

Routine liposuction has very low perioperative complication rates and is thus considered to be innocuous. Some authors have even proposed that large-volume liposuction could be therapeutic. However, because subcutaneous adipose tissue has nutritional and thermodynamic metabolic functions proportional to the absolute amount and the distribution of fat, it is possible that removal of subcutaneous adipose tissue might be detrimental. We measured the amount of fat removed by large-volume (>1000 cc) liposuction and expressed the results in terms of absolute and relative changes in total body fat and in visceral adipose tissue (nonsubcutaneous adipose tissue) in 63 normal weight to mildly obese women (n = 51) and men (n = 12). Aspiration of 1.5 +/- 0.7 kg (mean +/- SD) of lipid in women removed 9.2 +/- 3.2 percent of body fat or 10.5 percent of subcutaneous adipose tissue corresponding to a 12-percent increase in the ratio of visceral to subcutaneous adipose tissue. One third of the women (n = 17) had a mean increase of 16 percent (range 13 to 21 percent) in the proportion of visceral fat. In the 12 men, aspiration of 1.7 +/- 0.6 kg of lipid removed 9.8 +/- 2.9 percent of body fat or 12.7 +/- 3.6 percent of subcutaneous adipose tissue, resulting in a 14-percent increase in the ratio of visceral to subcutaneous fat. The correlation between aspirate and body mass index was 0.57 (p < 0.001). Although large-volume subcutaneous liposuction removed relatively little body fat, it led to significant increases in the proportion of visceral adipose tissue. Because the proportion of visceral adipose tissue is a risk factor for metabolic complications of obesity, the metabolic effects of large-volume liposuction need to be evaluated.     

The relationship between follicular fluid aspirate volume and oocyte maturity in in-vitro fertilization cycles

As a consequence of multiple follicular growth during ovarian stimulation for in-vitro fertilization (IVF), follicles of varying sizes often yield oocytes that vary in maturity and morphology of the oocyte-cumulus-corona complex. The objective of this prospective study was to explore the relationship between follicular fluid aspirate volume and the oocyte's developmental potential in an IVF treatment cycle. In total 9933 follicles were studied from 400 patients who underwent 535 consecutive IVF treatment cycles at St James's University Hospital, Leeds, UK, between February 1995 and February 1996. The volume of each individual follicle aspirated was recorded and related to the probability of obtaining an oocyte, its fertilizing capacity, the cleavage rate and the quality of embryos derived. We found no statistically significant difference in oocyte recovery rates between follicles with an aspirate volume < or = 1 ml and follicles with a volume > 1 ml. Although oocytes obtained from follicles with an aspirate volume > or = 1 ml showed a significantly lower fertilization rate, they went on to cleave at the same rate as oocytes obtained from larger follicles and resulted in embryos of comparable quality. Furthermore, there was no statistically significant difference in the implantation, clinical pregnancy or live birth rates per cycle between embryos derived from follicles with an aspirate volume < or = 1 ml and those derived from follicles with an aspirate volume > 1 ml. We conclude that follicular size and the oocyte's developmental potential in the stimulated ovary are not closely related and can be independent. This is in contrast to the Graafian follicle and the pre-ovulatory oocyte in the natural cycle.     

Suppression of kindling epileptogenesis in rats by intrahippocampal cholinergic grafts

The objective of our study was to investigate the effects of ultrasonic energy on tissues, using a porcine model, performed under various instrumental and procedural parameters. Domestic pigs were anesthetized and prepared for surgery. An incision was made on the side of the hip randomly assigned to the right or left side. Tumescence solution was infiltrated via a blunt tip, small diameter cannula, followed by performance of standard liposuction. On the contralateral side, a similar incision was made. For ultrasonic liposuction experiments without the sheath, a percutaneous introducer was inserted into the incision, which was protected at the entry site from contact with the cannula. Tumescence solution was infiltrated via a blunt tip, small diameter cannula, and then the site was treated with ultrasonic energy at maximum output from the machine with liposuction concurrent through the hollow cannula. The experiments with the sheath did not require a pretreatment with tumescence solution but consisted of tumescence solution pumped through the sheath at a low infusion rate, with concurrent treatment utilizing ultrasonically assisted liposuction through the central lumen of the cannula. In all cases, the lipoaspirate was preserved for biochemical analysis. After treatment, the pigs were euthanized, and samples for histopathology were taken. The pigs were then perfused with a radio-opaque solution through the left ventricle following preperfusion with saline. The groups were ultrasound-assisted liposuction with sheath (n = 3), ultrasound-assisted without sheath (n = 4), and tumescence alone (n = 1), with standard liposuction performed on the contralateral side for all ultrasound-assisted liposuction animals. The lipoaspirates from the ultrasonically assisted liposuction with the sheath showed significantly less blood loss (measured as hemoglobin in the aspirate) than standard liposuction (p = 0.012) at comparable levels of fat (measured as triglycerides in the aspirate). The lipoaspirates from ultrasound-assisted liposuction without the sheath showed blood loss comparable to that experienced with standard liposuction. The ratio of hemoglobin to triglyceride was lowest in the ultrasound-assisted group with (p = 0.01) and without (p = 0.06) the sheath when compared to traditional liposuction. In both of these treated groups, the radiograms of the perfused areas showed significantly less vascular disruption when compared with suction-assisted liposuction. Histopathologic examination of specimens taken from various treated areas showed substantial tissue damage comparable in ultrasound- and suction-assisted liposuction treated groups. This preliminary experimental study showed that ultrasound-assisted lipoplasty is comparable to traditional suction-assisted lipoplasty. Treatment with ultrasound provided more significant hemoglobin/triglyceride ratios, indicative of more lipid aspirated per hemoglobin lost, and better preservation of vascular tissues as demonstrated by our perfusion studies. Treatment with the sheath showed a significantly lower hemoglobin release with a diminished volume infused into the subcutaneous space during the procedure.     

Tumescent anesthesia with a lidocaine dose of 55 mg/kg is safe for liposuction

BACKGROUND: The safe upper limit of lidocaine dosage in tumescent anesthesia for liposuction has been reported to be 35 mg/kg. OBJECTIVE: This study was undertaken to: 1) evaluate the safety of tumescent anesthesia in liposuction when lidocaine doses greater than 35 mg/kg are required, 2) determine the time interval when the peak plasma lidocaine level occurs following administration of tumescent anesthesia, and 3) assess if the safety of large volume tumescent anesthesia is due to significant lidocaine removed by liposuction. METHODS: Sixty patients who underwent liposuction with a mean lidocaine dose of 57 mg/kg were prospectively evaluated for development of any signs or symptoms of lidocaine toxicity by multiple interviews over a 24-hour period. In addition, another 10 patients who received a mean lidocaine dose of 55 mg/kg had serial plasma lidocaine level measurements over a 24-hour period following liposuction. The lidocaine level of the aspirate was also measured to assess any significant lidocaine removed by liposuction. RESULTS: No evidence of lidocaine toxicity was found based on subjective evaluation of 60 patients as well as determined by plasma sampling of 10 patients. The peak plasma lidocaine concentration occurred at approximately 4 or 8 hours after infusion of tumescent anesthesia. The 24-hour plasma lidocaine level suggests that residual lidocaine is present in the subcutaneous tissue allowing for postoperative analgesia beyond this time. A negligible amount of lidocaine was removed by liposuction as determined by the lidocaine level of the aspirate. CONCLUSION: This study suggests that tumescent anesthesia with a total lidocaine dose of up to 55 mg/kg is safe for use in liposuction.     

Extending the role of liposuction in body contouring with ultrasound-assisted liposuction

The initial experience with ultrasound-assisted liposuction in treating difficult fibrous areas, such as gynecomastia, hitherto not uniformly responsive to traditional suction-assisted lipoplasty, has led to the evolution and improvement of ultrasound-assisted liposuction techniques. This prospective study examined 114 consecutive patients treated with ultrasound-assisted liposuction over a 13-month period, from September of 1996 to September of 1997. The means by which this procedure helps achieve fat contouring differs from that of suction-assisted lipoplasty. Ultrasound-assisted liposuction removes fat through a fat emulsification process termed "cavitation," whereas suction-assisted lipoplasty achieves contouring through the mechanical avulsion of fat. The technique for the use of ultrasound-assisted liposuction has changed significantly from our initial series of patients to our current technique. To optimize the benefits of both ultrasound-assisted and traditional suction-assisted lipoplasty, we use a three-stage technique consisting of infiltration, ultrasound-assisted sculpturing, and suction-assisted lipoplasty for evacuation and final contouring. This has decreased our operative time, minimized complications, and optimized our body contouring results. Data were collected intraoperatively, including treatment times, treatment volumes, and treatment areas for both suction-assisted and ultrasound-assisted lipoplasty. A total of 114 patients were treated with ultrasound-assisted liposuction between September of 1996 and September of 1997. There were 23 male patients and 91 female patients. In general, the average total volume removed with this procedure decreased by about 50 percent throughout the series, whereas the suction-assisted lipoplasty volume increased correspondingly by 50 percent. Overall, suction-assisted lipoplasty volume was approximately two times ultrasound-assisted liposuction volume in the same area. Exceptions to this include the dense fibrous areas such as the back and male breast, where aspiration volumes were approximately equal. The total ultrasound-assisted liposuction treatment times were reduced after our initial 30 patients, and suction-assisted lipoplasty times increased. Total aspiration rates in our later patients averaged 36.2 cc/per minute for ultrasound-assisted and 58.4 cc/per minute for suction-assisted lipoplasty, whose rates were approximately 1.5 to 2 times faster than for ultrasound-assisted liposuction in most areas. After using this technology in our initial series of 30 patients, it became apparent that ultrasound was not a substitute for suction-assisted lipoplasty but rather a natural complement. We have found that the marriage of the techniques enhances results and minimizes complications, such as seromas, which have been reported to be 11.4 percent with ultrasound-assisted liposuction alone and are 2.6 percent in our series.     

A prospective study of Clostridium difficile infection and colonization in pediatric oncology patients

BACKGROUND: Tumescent liposuction has proven to be an extremely safe and effective method of liposuction. However, the infusion of tumescent anesthesia can take 1 hour or more to complete. OBJECTIVE: To document the types, dosages, and routes of administration of premedication utilized by four experienced tumescent liposuction surgeons. To determine if infusion rates for tumescent anesthesia are affected by types of premedication. METHODS: Four experienced liposuction surgeons were asked to review their most recent 100 tumescent liposuction patients with respect to types and dosages of premedication and routes of administration. Data were also provided on corresponding infusion pump settings and infusion rates. Volumes of tumescent anesthesia and corresponding volumes of fat aspirated were also collected on the same 400 patients. RESULTS: Infusion of tumescent anesthesia could be performed more rapidly in patients who were given greater amounts of premedication. Volumes of tumescent anesthesia infused were generally two or more times the volume of fat aspirated. Patients could be infused with less premedication if slow infiltration was employed. CONCLUSION: Infusion rates for tumescent anesthesia can be increased of greater amounts of premedication are given. However, this must be balanced against the safety of the premedication.     

Interaction of transport resistances with biochemical reaction in packed-bed solid-state fermentors: effect of temperature gradients

Subdermal superficial liposuction, first presented by the authors at the ISAPS Congress at Zurich in 1989, is performed with thin three-hole Mercedes cannulas (diameter ranges from 1.8 to 2 mm) to treat small and secondary adiposities and to allow better skin retraction. Suction of the subdermal layer of fat reduces the thickness and consistency of the superficial fat and enhances the possibility of skin retraction. In cases where there is a large adiposity of the abdomen, arms, or inner thighs, there is a conspicuous volume of fat whose weight tends to overstretch and to carry the overlying skin downward. In these cases we need to reduce the large fat volume to permit effective skin retraction. Therefore, we apply the principles of traditional liposuction with those of subdermal superficial liposuction to aspirate large amounts of fat from all the adipose layers. We call this technique Massive All Layer Liposuction (MALL). The amount of skin shrinkage after this "defatting" procedure is remarkable and the clinical results are very good. The MALL technique can be applied to other areas as well. In our experience this new liposuction technique has dramatically reduced the indications of abdominoplasties and dermolipectomies of inner thighs and arms.     

Effects of doxycycline in actively purging cholera patients: a double-blind clinical trial

In 51 actively purging cholera patients the efficacy of doxycycline, a long-acting tetracycline, was compared with a placebo and tetracycline hydrochloride. Seventeen patients who were given doxycycline at the recommended dose of 2 mg/kg at the beginning of the study, at 12 h, and at the repeated dose once daily purged a mean volume of 5.1 liters of stool and received an average of 5.7 liters of intravenous fluid. Nineteen patients receiving the placebo purged 10.1 liters of stool and received 9.7 liters of fluid. Fifteen patients given tetracycline hydrochloride at 6-h intervals passed 4.8 liters of stool and received 5.5 liters of fluid. The durations of diarrhea calculated in 8-h periods were 3.5, 8.0, and 4.1 h in the respective groups receiving doxycycline, placebo, and tetracycline. The differences between the doxycycline and placebo treatments and the tetracycline and placebo treatments were statistically significant. Those receiving doxycycline became vibrio-free in about 3 days as compared with 2 days for those receiving tetracycline; the group given the placebo were vibrio positive for the duration of their hospitalization. The results show that in the treatment of cholera the administration of doxycycline once daily has effects equal to those when tetracycline is administered at 6-h intervals. This is a distinct advantage because it decreases the demand on nursing personnel in epidemics. Also, doxycycline may be safely administered in cases of suspected renal failure from prolonged shock in cholera.     

Sequential hemodynamic changes for large volume paracentesis in post-hepatitic cirrhotic patients with massive ascites

Large volume paracentesis (4.8 to 15.5 liters) was performed in 42 patients with post-hepatitic cirrhosis and massive ascites, not only to derive parameters capable of predicting the development of severe clinical hypotension after large volume paracentesis, but also to determine the optimal time to introduce preventive volume expanders. Systemic hemodynamics were sequentially measured for 72 hours in thirty-two patients. Severe clinical hypotension occurred in 13 (31.0%) patients 4-62 hours from the start of paracentesis. Univariate analysis, with the Mantel-Cox test used to compare Kaplan-Meier curves, and the subsequent multivariate analysis by stepwise Cox regression procedure were utilized to identify two variables, withdrawn ascitic fluid greater than 7.5 liters (p = 0.0121) and the absence of peripheral edema (p = 0.0148), reaching statistical significance to predict the occurrence of severe clinical hypotension. Compared to the baseline value, the cardiac output of patients not developing severe clinical hypotension increased (6.26 +/- 0.66 vs. 6.65 +/- 0.69 liter/min, p < 0.01) one hour from the start of paracentesis and right atrial pressure decreased (11.2 +/- 2.4 vs. 8.7 +/- 2.3 mmHg, p < 0.05). The cardiac output returned to the baseline value at the 9th hour. Based on the results presented herein, we can conclude that severe clinical hypotension occurs in a high percentage of patients with post-hepatitic cirrhosis and massive ascites within 72 hours from the start of large volume paracentesis. At potential risk of this occurring are those patients without peripheral edema and withdrawn ascitic fluid greater than 7.5 liters. Volume expanders should be introduced before 4th hour from the start of large volume paracentesis.     

The effects of varying volumes of crystalloid administration before cesarean delivery on maternal hemodynamics and colloid osmotic pressure

The value of intravenous crystalloid administration in preventing spinal-induced hypotension in the parturient has recently been questioned. Also, the association between increasing crystalloid volume and decreasing postpartum colloid osmotic pressure (COP) raises concern regarding the risk of maternal and fetal pulmonary edema. To study the dose-response effect of varying amounts of crystalloid volume prior to spinal anesthesia, we measured maternal hemodynamic variables and maternal and fetal COP in three groups of healthy parturients receiving spinal anesthesia for elective cesarean delivery. Fifty-five parturients were randomized in a double-blind fashion to receive one of 10, 20, or 30 mL/kg of crystalloid volumes prior to induction of spinal anesthesia. Measurements included mean arterial blood pressure (MAP), cardiac index (CI), and systemic vascular resistance index (SVRI) recorded using noninvasive thoracic impedance monitoring until delivery. Maternal and neonatal COP were measured. All groups showed declines in MAP and SVRI from baseline at 5 min after spinal anesthesia, but the amount of decline did not differ among groups. Total ephedrine and additional intravenous (i.v.) fluid administered did not differ among groups. The 20- and 30- mL/kg groups showed a larger decline in maternal COP than the 10-mL/kg group; no differences in neonatal COP were seen with varying preload. We conclude that increasing the amount of i.v. crystalloid administered to 30 mL/kg in the healthy parturient does not significantly alter maternal hemodynamics or ephedrine requirements after spinal anesthesia and has no apparent benefit.     

Comparison of the effect of two dose schedules of oral omeprazole with oral ranitidine on gastric aspirate pH and volume in patients undergoing elective surgery

We have compared gastric aspirate pH and volume at induction of anaesthesia in 222 patients who had received either omeprazole or ranitidine before elective operations. Omeprazole was given orally either as 40 mg on the evening before and 40 mg on the morning of surgery or as 80 mg on the morning of surgery. Ranitidine 150 mg was given orally on the evening before surgery and 2 h before anaesthesia. Treatment success was defined as aspirate pH > or = 2.5 and volume < 25 ml at induction of anaesthesia. Treatment was successful in 84% (95% confidence interval (CI) 73-91%) of patients in the omeprazole 40 + 40 mg group, 84% (95% CI 73-91%) in the ranitidine group and 73% (95% CI 61-83%) in the omeprazole 80 mg group. There were no statistically significant differences between the groups. Twelve patients in the omeprazole 80 mg group had gastric pH < 2.5 and four had volume > 25 ml. Only three patients had a gastric pH < 2.5 in the omeprazole 40 + 40 mg group and none had volume > 25 ml, which compared well with the ranitidine group. Omeprazole, given as 40 mg in the evening and 40 mg on the morning of operation, has a potential role for use in patients at risk for aspiration during general anaesthesia.     

A prospective study of the safety of joint and soft tissue aspirations and injections in patients taking warfarin sodium

OBJECTIVE: To determine the safety of joint or soft tissue aspirations and injections in patients taking warfarin sodium. METHODS: The outcome of 32 joint or soft tissue aspirations or injections in patients receiving stable doses of warfarin sodium was assessed through a standardized interview 4 weeks after the procedure. The primary outcome measure was significant joint or soft tissue hemorrhage, ascertained by patient-reported increases in swelling or warmth at the procedure site. RESULTS: None of 32 procedures was complicated by joint or soft tissue hemorrhage reported by the patients, yielding, by the "rule of threes," a risk of significant hemorrhage of < 10% (with 95% certainty). Diagnostic information was obtained for 53% of aspirated sites (8 of 15) and therapeutic benefit was noted in 74% of corticosteroid-injected sites (17 of 23). CONCLUSION: Joint or soft tissue injections and aspirations in selected patients taking warfarin sodium are associated with a low risk of hemorrhage and are often of diagnostic or therapeutic value.     

Morphologic prognostic factors of malignant mixed müllerian tumors of the ovary: a clinicopathologic study of 15 cases

Interleukin-2 (IL-2)-based therapy induces a vascular leak syndrome (VLS), manifested by hypotension, tachycardia, and oliguria, as is also seen with septic shock. The optimal method for treating such VLS is not known. A prospective randomized trial was undertaken to compare crystalloid and colloid fluid resuscitation for patients receiving bolus IL-2-based therapy for metastatic cancer. All patients received maintenance crystalloid fluid administration and were randomized to receive crystalloid (0.9% normal saline) or colloid (5% human serum albumin) fluid boluses to maintain acceptable vital signs and urine output. Patients refractory to fluid boluses were given dopamine for oliguria and/or phenylephrine for hypotension. Of 107 patients who completed one cycle of therapy on study, 76 completed a full treatment course (two cycles) on study. The total number of saline and albumin fluid boluses given were 9.5 +/- 0.9 versus 7.7 +/- 0.7 (p = 0.36, n = 107) for the first cycle and 19.2 +/- 1.8 versus 16.1 +/- 1.6 (p = 0.33, n = 76) for a complete course, respectively. Although patients receiving saline boluses had significantly more oliguria during a course of therapy, weight gain, number of IL-2 doses, tachycardia, hypotension, vasopressor use, hospital stay, and clinical response rates did not significantly differ between arms. Changes in hematocrit, hemoglobin, protein, albumin, blood urea nitrogen (BUN), and creatinine were analyzed, and patients receiving crystalloid showed greater decreases in albumin (p < 0.0001) and total protein (p < 0.05) as expected. A 40-fold greater cost associated with albumin suggested that crystalloid resuscitation be used to treat the VLS associated with IL-2 therapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

The relationship of level of habitual activity to measures of leanness-fatness, physical working capacity, strength and motor ability in 17 and 18 year-old males

The influence of one hemodialysis session and of subsequent loading by 1.5-2 liters N saline on blood pressure, PRA and body fluid compartments was assessed in seven patients with chronic renal failure on maintenance hemodialysis. Dialysis caused only slight decreases in plasma volume, ECV and in TEBS. Lying mean blood pressure by 5-10 mm Hg and PRA increased by 30%. Saline loading resulted in a significant increase in plasma volume by 0.4 liters and in blood pressure by 10-5 mm Hg, but in a decrease in PRA by 40%. The changes in mean blood pressure correlated positively with the changes in plasma volume, and negatively with the changes in PRA. It is concluded that the renin-angiotensin system in patients on chronic hemodialysis still functions as one of the adjustment mechanisms for the circulatory homeostasis, when challenged by volume loss or volume and sodium loading.     

Large-volume liposuction and extensive abdominoplasty: a feasible alternative for improving body shape

Forty-two female patients underwent liposuction of large volumes and extensive abdominoplasty during an 18-month period, with an average follow-up period of 9 months. Fifty-two percent of the patients underwent a third surgical procedure, which was basically aesthetic. The average age was 40 years; weight varied between 51 kg and 113 kg, with only 11 percent of the patients at their ideal weight. The tumescent technique was used for performing liposuction, which was done on the loins, trochanters, lumbar, upper scapular, and upper lateral abdominal regions, avoiding liposuction of the abdominal flap in all cases except for one. The abdominoplasty was extensive with detachment to the xiphoid process without detaching liposuctioned areas. Volumes of 1600 ml to 11,200 ml were obtained through liposuction, with an average of 4230 cc, and minimal blood loss. Fatty dermal tissue was removed through abdominoplasty and it varied between 400 g and 5000 g with an average of 1300 g. Only the two heaviest patients required an autologous blood unit, because they underwent breast reduction at the same time. All the other patients were managed exclusively with intravenous crystalloids solutions. No major complications arose, and only five patients had minor complications. Based on these results, we consider it to be feasible to combine the liposuctioning of large volumes with abdominoplasty to improve body shape, even with the addition of a third surgical procedure. Nevertheless, it is essential to use the tumescent technique for liposuction to reduce bleeding to a minimum and to allow us to perform other procedures.     

Effects of crystalloid solutions on circulating lactate concentrations: Part 1. Implications for the proper handling of blood specimens obtained from critically ill patients

OBJECTIVES: a) To test the hypothesis that circulating lactate concentrations are the same in simultaneously collected arterial and central venous blood specimens; b) to test the hypothesis that even small amounts of crystalloid solutions, which are inadequately "cleared" from these indwelling arterial and venous catheters, can lead to clinically important and misleading changes in the measured lactate values. DESIGN: A prospective, multiexperiment study. SETTING: A critical care research laboratory and a 20-bed intensive care unit (ICU). PATIENTS: Three hundred fifty-five patients. INTERVENTIONS: Blood samples were collected. MEASUREMENTS AND MAIN RESULTS: Experiment 1: Simultaneously collected arterial and central venous blood specimens were obtained on 148 occasions from 48 medical ICU patients receiving no lactated Ringer's solution (RL). Arterial and central venous lactate values were nearly identical in these patients. The correlation between the arterial and central venous lactate concentrations was excellent (r2 = .85; p < .0001) and the agreement between the arterial and central venous lactate concentrations was also excellent (bias and precision = 0.04 mmol/L and +/- 0.38 mmol/L, respectively). Experiment 2: Arterial and mixed venous blood samples were obtained from 100 percutaneous transluminal coronary angioplasty (PTCA) and 75 cardiac surgical patients immediately before the performance of these cardiac procedures. We found the central venous lactate concentrations to be higher than arterial lactate values in the cardiac surgical group, and there was a very poor correlation (r2 = .07) between arterial and central venous lactate values in the cardiac surgical group. The correlation between central venous and arterial lactate concentrations in the PTCA patients was excellent (r2 = .84) and similar to the findings of experiment 1. Since the cardiac surgical patients received RL and the PTCA patients received no RL, we speculated that the intravenous infusion of RL in the cardiac surgical group accounted for these discordant findings. To test this speculation, we performed experiments 3 and 4. Experiment 3: In a large bench study, blood specimens were divided into multiple 1-mL aliquot portions, to which 0.01, 0.05, 0.10, 0.50, or 1.0 mL of various crystalloid solutions, containing or not containing RL, were added. In a volume-dependent and linear manner, solutions containing RL increased the circulating lactate concentration from 10% to > 400% of the baseline lactate value. In a volume-dependent and linear fashion, the non-RL crystalloid solutions decreased the lactate concentration by 0 to 66% of the baseline nondiluted lactate concentration. Experiment 4: In 30 different cardiac surgical patients, we simultaneously obtained central venous and arterial blood specimens. Patients this time received no RL, and catheter lines were adequately cleared (removal > 5 mL) of crystalloid solutions. We found a correlation (r2 = .82; p < .0001) that was virtually identical to the findings of experiment 1 and to the findings in the PTCA group of experiment 2. CONCLUSIONS: a) Arterial and central venous lactate concentrations are similar in hemodynamically stable critically ill patients, b) Even small amounts of RL-containing solutions in catheters used for blood sampling may cause false increases in the circulating lactate concentration. c) Even small amounts of non-RL crystalloid solutions in catheters used for blood sampling may falsely decrease circulating lactate values. d) When blood specimens are drawn from indwelling catheters, all crystalloid solutions must be cleared from the line.     

Hepatitis C. Issues for women and their partners

OBJECTIVE: To evaluate the diagnostic accuracy of transvaginal ultrasonography in detecting and measuring free pelvic fluid. STUDY DESIGN: Eighty-two patients undergoing diagnostic or therapeutic laparoscopy at a tertiary care center were prospectively assessed before surgery by transvaginal ultrasound. Free pelvic fluid was measured in two ultrasonographic planes. These measurements were compared to the volume of fluid aspirated during laparoscopy. RESULTS: The mean volumes reported for transvaginal ultrasound were significantly lower than those observed at laparoscopy (mean milliliters +/- SEM, 2.54 +/- 0.5 versus 9.42 +/- 1.3, P < .001). The smallest volume of free pelvic fluid that was consistently detected by ultrasound was 8 mL. Whenever no fluid or < 1 mL was detected by transvaginal ultrasound, a small volume of fluid was found at laparoscopy (mean milliliters +/- SEM, 1.6 +/- 0.47). The sensitivity of transvaginal ultrasound was 83% and specificity was 69%. CONCLUSION: Transvaginal ultrasound is a sensitive method of detecting the presence of > 8 mL of free pelvic fluid and therefore is an important diagnostic tool in the assessment of pelvic pathology associated with increased peritoneal fluid.     

Modest release of adipsin/factor D by liposuction when using the superwet or tumescent technique

Human adipsin is recognized to be identical to factor D, which plays an important role in activation of the alternative complement pathway. Since adipsin/factor D is present in high amounts in adipose tissue, liposuction theoretically could result in an increased release of this serine protease into the bloodstream. In the present study, adipsin/factor D was measured in 22 patients undergoing syringe-assisted liposuction using the superwet or tumescent technique. Despite a relatively high mean aspirate volume (2648 ml), only a very modest increase in adipsin/factor D concentration was found during liposuction. All values before, during, and after liposuction were within the range found in healthy blood donors. Furthermore, there was no correlation between adipsin/factor D values and C3 activation products. We conclude that liposuction with the present techniques results in a very modest release of adipsin/factor D that is not associated with increased complement activation.     

An argument for colloid resuscitation for shock

A focused review of the physiologic mechanisms of colloid and crystalloid fluid resuscitations for acute critical illness is presented. This review suggests that postresuscitation plasma volume, cardiac output, left ventricular mechanical performance, and global and microcirculatory O2 supplies are more favorable with colloid therapy. Conversely, crystalloid may adversely affect microcirculatory blood flow and resultant O2 supply and use by ischemic tissues in shock. Poor relief of global and regional hypoxia may persist in critically ill patients after resuscitation with crystalloid.