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S M Shulman

Publications and source records attributed to S M Shulman.

8 recordsLinked to original sources

The detection of peripheral venous pulsation using the pulse oximeter as a plethysmograph.

The pulse oximeter can serve as a sensitive photoelectric plethysmograph in the operating room. It was noted in several cases that the plethysmographic waveform showed a high degree of variability during diastole. Three patients are described with discrete diastolic peaks on the plethysmograph. Further investigation revealed that these diastolic peaks appear to correlate with peripheral venous pulsation, which seems to have a central venous origin. Evidence is presented that the plethysmographic detection of the venous-pulse may be useful in estimating the changing volume status of the patient.

Adult↗

Esmolol hydrochloride, sodium nitroprusside, and isoflurane differ in their ability to alter peripheral sympathetic responses.

To demonstrate that esmolol, sodium nitroprusside, and isoflurane differ in their abilities to alter adrenal medullary blood flow and other peripheral sympathetic responses to hypotension, 16 mongrel dogs anesthetized with pentobarbital were allocated randomly to one of four test groups and given two hypotensive stimuli, separated by 1 h, to a mean arterial blood pressure of 60 mm Hg for 10 min. The first stimulus, induced by blood loss into a pressurized bottle system, constituted the control for each animal. The second hypotensive stimulus was created by either repeat blood loss (Group 1), esmolol infusion (Group 2), sodium nitroprusside infusion (Group 3), or isoflurane administration (Group 4). Before and 10 min into hypotension, the variables of abdominal organ blood flow, adrenal medullary blood flow, arterial norepinephrine and epinephrine concentrations were measured. In the control animals (Group 1), comparable decreases in abdominal organ blood flow and similar increases in adrenal medullary blood flow, norepinephrine, and epinephrine were elicited by the first and second hypotensive stimulus. Esmolol-induced hypotension (Group 2) abolished the increase in adrenal medullary blood flow and attenuated the increase in epinephrine by 65% (P < 0.03). The decrease in abdominal organ blood flow and the increase in norepinephrine were similar to that observed during baseline hemorrhagic hypotension. In contrast, sodium nitroprusside-induced hypotension (Group 3) abolished abdominal organ vasoconstriction whereas the increases in adrenal medullary blood flow, norepinephrine, and epinephrine were comparable to baseline hemorrhagic hypotension. In fact, abdominal organ blood flow increased 2.5-fold (P < 0.001) during hypotension with SNP. Isoflurane 2%, 1.54 minimum alveolar anesthesia concentration (Group 4), abolished the increases in adrenal medullary blood flow, norepinephrine, and epinephrine observed during baseline hemorrhagic hypotension and attenuated the decrease in abdominal organ blood flow by 70% (P < 0.001). These data demonstrate that esmolol, sodium nitroprusside, and isoflurane differ radically in their ability to alter or blunt peripheral sympathetic responses to hypotension, and suggest that isoflurane is the drug most effective in blunting multiple responses of the peripheral sympathetic system.

Adrenergic beta-Antagonists↗

Dynamic respiratory patterns after laparoscopic cholecystectomy.

Important alterations in respiratory function have been observed after open cholecystectomy. These include a decrease in the abdominal tidal volume, forced vital capacity, and forced expiratory volume at 1 s. Laparoscopic cholecystectomy is a new procedure allowing removal of the gallbladder without a subcostal or midline incision. The result is less postoperative pain and earlier ambulation. This study sought to determine whether changes in rib cage and abdominal wall motion are different after laparoscopic than open cholecystectomy. Twelve otherwise healthy patients underwent respiratory inductive plethysmography prior to and one day after laparoscopic cholecystectomy. Frequency of resting breathing increased 29 percent after laparoscopic cholecystectomy (p = 0.03), while abdominal motion decreased 32 percent (p = 0.03). During coached abdominal breathing, rib cage tidal volume increased 70 percent (p = 0.005) and abdominal tidal volume decreased 29 percent (p = 0.01). These alterations in respiratory pattern after laparoscopic cholecystectomy were smaller in magnitude than those reported following the open procedure.

Adult↗

How to use a computerized data base for ward management.

As you well know, patient information must be collected, recorded, and communicated to attendings and other house staff on a daily basis. This tedious process can be improved with the use of a computerized data base. In this article, the authors discuss the ease with which this data base can be implemented and its various advantages.

Data Display↗

Preserving central blood volume: changes in body fluid compartments during hemodialysis.

The understanding of fluid changes during hemodialysis (HD is essential for reducing complications as well as efficacy of the procedure. Bioimpedance spectroscopy provides a non invasive method of measuring total body water (TBW), the distribution of intra (ICF) and extracellular (ECF) fluids, and their changes during HD. Segmental bioimpedance may be used to measure the same fluid shifts but from different body segments; the technique has previously been shown to com pare well with whole body measures. It is possible that fluid shifts occur differently in different body compartments during HD. Based on previous hemodynamic studies we postulated that during HD ultrafiltration (UF) the body attempts to preserve its central blood volume (cardiopulmonary circula tion plus great vessels), and thus fluid shifts would be greater from the periphery than from central compartments. To test this hypothesis, segmental bioimpedance (Xitron Technolo gies, San Diego, CA) was performed on 11 subjects undergoing HD where ECF and ICF values were obtained from the legs, arms and trunk before and after a period of UF. Blood volume change (ABV%) was also followed using an on-line optical hematocrit (Hct) sensor (Crit-Line monitor, In-Line Diagnostics, UT) where deltaBV% = deltaBV% = (1 - Hct1/Hct0) x 100 (Hct0 = baseline Hct; Hct1 = postultrafiltration Hct) The UF of 2.0 L +/- 0.79 L (M +/- SD) over 75 minutes was associated with a deltaBV% of -9.43% +/- 3.6% (M +/- SD), a significant (Student's paired t-test) reduction in total body (TB) ECF (p < 0.02), a weak correlation in reduction in TBW (p = 0.09) but not in TB ICF. The ECF reductions from the trunk, legs, and arms were all significant (minimum p < 0.02); no ICF changes from these compartments were significant. The amount of ECF reduction was greater from the legs (0.7 L +/- 0.6 L) than the arms (0.12 L +/- 0.08 L) and trunk (0.2 L +/- 0.2 L) (all M +/- SD). Multiple regression analysis showed that TB ECF changes correlated strongly with leg (r = 0.94, p < 0.001) and arm (r = 0.72, p = 0.002) ECF changes but not with trunk changes. deltaBV% correlated weakly with leg (r = 0.45, p = 0.08) and arm (r = 0.42, p = 0.10) ECF changes but not with the trunk. As the deltaBV% represents the net volume change between UF and plasma water refilling, thiss indicates that plasma water is being removed more from the peripheral compartments than from the trunk. These data suggest that plasma refilling during HD to preserve central blood volume is more dynamic from the leg ECF than from elsewhere and may, in turn, explain the frequent occurrence of leg cramps during and after hemodialysis.

Blood Volume↗