:

Uterine Vascular Bed: Effects of Acute Hyperoxia

Frank G. Greiss, Jr., M. D. Stephen G. Anderson, M. D.

Lorraine C. King,_@. D.

From the Section on Reproductive Biology, Department of Obstetrics and Gynecology, Bowman Gray School of

Medicine of Wake Forest University, Winston-Salem, N. C.

Abstract

The acute effects of inspiration of 100 percent oxygen on

.the uterine vascular beds of castrated and pregnant ewes were

evaluated in a chronic conscious preparation. In castrated ewes,

vascular conductance decreased to 90.8 f 17.9 S. D. percent of

control levels. During pregnancy, no significant changes in

conductance occurred. The results suggest that acute maternal

hyperoxia causes essentially no change in placental blood flow.

‘L’

I il

This investigation was supported by United States Public Health

Service Grant No. HE-03941-13 from the National Heart Institute.

AUTONOMIC RESPONSES IN.THE FETAL LAMB FOLLOWING GENERAL OR CONDUCTION

ANESTHESIA INTHE MATERNALEWE. R. 0. Bauer, C. R. Brinkman, B. Nuwayhid,

N. S. Assali. University of California School of Medicine, Dept. Ob-Gyn

and Anesthesiology, Los Angeles, Calif.

The interaction of general or conduction anesthesia administered to

the maternal ewe and the response of the fetal cardiovascular system to

parasympathetic and sympathetic stimuli were investigated. Parasympathetic

and sympathetic reflexes controlling heart rate, ventricular output, systemic

arterial and pulmonary pressures were investigated in fetal lambs between

50-60 days and term gestation as follows: Jarisch-Bezold (Veratridine-

stimulation, atropine blocking); stretch receptors (atria1 stretching-

stimulation, atropine blocking); adrenergic 6 receptors (epinephrine or

norephinephrine-stimulation, guanathedine or phenoxybenzamine-blocking);

adrenergic p receptors (isoproterenol-stimulation, propranolol-blocking).

Results show: a) Jarish-Bezold bradycardic vagal reflex appears only

near-term fetuses and is blocked by atropine; in the premature fetus,

veratridine elicits a centrally mediated reflex tachycardia through p

in

stimulation which can be blocked by propranolol; b) atria1 stretch receptors

are present in both premature and term fetuses and can be blocked by atropine;

c) vascular g and g adrenergic receptors appear near term but their effect

on peripheral resistance is damped by the placental circulation; d) cardiac

adrenergic @ receptors were present in all fetuses studied; they can be'

stimulated by both norepinephrine and isoproterenol and blocked by propranolol.

There are noaadrenergic receptors in the fetal lamb heart. Potent general

anesthetic (halothane) administered to the ewe in these experiments severely

-2-

damped or obliterated the fetal response. Nitrous oxide in oxygen in

graded concentrations produced graded depressions of these responses

but did not obliterate them. CMxbternal spinal anesthesia had no effect

'on the fetal circulation.

PREGNANCY DECREASES ANESTHETIC REQUIREMENT OF INHALED AGENTS.

R. Palahniuk, M.D., S. M. Shnider, M.D. and E. I. Eger, II, M.D.

We evaluated the effect of pregnancy on anesthetic require-

ments of inhal.ation agents. The minimum alveolar concentration

(MAC) of halothane, methoxyflurane and isoflurane (Forane) re-

quired to prevent movement after a standard stimulus was deter-

mined in six pregnant and in six nonpregnant sheep. The pregnant

'sheep were all within two weeks of term. No drugs other than

the inhalation anesthetic and oxygen were used. Respiration was

controlled, temperature monitored and blood pressure measured

frequently.

Pregnancy was associated with a significant reduction in

MAC of 32 per cent for methoxyflurane, 25 per cent for halothane,

and 40 per cent for isoflurane (see table). Neither blood pres-

sure nor temperature differences appeared between the pregnant

and nonpregnant sheep. The cause of the lower MAC in pregnant

sheep is not known but may well relate

titularly an increase in progesterone.

to hormonal changes, par-

Methoxyflurane

Halothane

Isoflurane

Table

Nonpregnant

0.26 + .02

0.97 +* .04 -

1.58 +_ .07

Pregnant

0.18 2 .Ol

0.73 .07 +_

1.01 t .06

The table summarizes our results. Each value represents the

mean and standard error for MAC in six sheep.

ON THE REACTIVITY OF THE UTERINE VASCULAR BED TO ADRENERGIC STIMULATION

M. D. Barton, A. P. Killam, G. Meschia

Killam et al (Ref. 1) have recently developed a method in the unanes-

thetieed sheep that allows the measurement of blood flow in both uterine arteries

together with the infusion of estrogen into one of the uterine arteries. This paper

examines the possibility that this method is applicable to a study of other vasoactive

substances. Method: Uterine artery flow meters and infusion catheters were implanted

in sheep at least 3 days before the study.

Consider equation (1):

arterial concentration of drug (c) = rate of drug infusion mg/min (a) (1) arterial blood flow ml/rnin (b)

If (a) and (b) are known, then (c) can be calculated. Epinephrine and norepinephrine

solutions of a known concentration were infused at known rates into a side branch of the

uterine artery below the flowmeter implantation site. After varying periods of infusion,

a period of equilibrium was achieved where uterine artery flow had reached a new low

steady state. Table 1 shows data obtained from epinephrine infusions into the uterine

artery of a pregnant ewe.

:

From such data, dose response curves of uterine artery flow to epinephrine

and norepinephrine infusion were constructed in pregnant, castrated, and castrated

but estrogen stimulated ewes. Dose response curves for pregnant, and castrated,

:I but estrogen stimulated ewes were similar for both epinephrine and norepinephrine.

1 i Interpolation of these uterine artery flow dose response curves shows a 50% decrease

:’ 1: L in’uterine blood flow achieved by a norepinephrine concentration from 2 to 10 nanograms/ I

j ml of blood. A 50% decrease of flow also occurs after an epinephrine concentration

II

of 3 to 13 nanograms/ml of blood.

Additional data was obtained while infusing epinephrine

In these animals, low infusion rates of epinephrine (2-ng to 20

into castrated ewes.

ng/min. ) produced

only vasoconstriction whereas higher infusion rates (greater than 20 ng/min. )

produced vasoconstriction followed by vasodilation. During infusion rates greater

than 20 nglmin., blood flow was reduced to undetectable levels and calculations of

blood concentrations of epinephrine were not possible. The increase of flow after

cessation of infusion was proportional to the original infusion rate; higher infusion

rates producing higher postinfusion flows. After the 5 minute infusion of 1.2 mgm

of propranolol into the uterine artery, the increase of uterine artery flow over

control levels following the cessation of epinephrine infusion was no longer seen.

Infusion of epinephrine into estrogen stimulated uterii, or into pregnant uterii

produced only vasoconstriction.

CONCLUSION: This method of in vivo uterine artery infusion is well suited for --

precise quantitative analysis of the reactivity of the uterine artery bed to pharma-

cologic agents. 2. The uterine vascular bed appears extremely sensitive to

alpha adrenergic stimulation. Beta adrenergic reactivity can be demonstrated only

if estrogen levels are very low. Beta adrenergic vasodilitation..of the non pregnant

uterine vascular bed is proportional to the dose of epinephrine infused.

1 Killam, A p., Rosenfeld, C., Makowski, E., Battaglia, F., Me=hk Go

Am. J. Obstet. Gynec. (in press)

TABLE 1. NUMERICAL DATA DERIVED FROM THE EXPERIMENT OF EPINEPHRINE (E) INFUSION INTO A PREGNANT EWE

LL-^^.--.“... _____. -.. __ t ,’

. . .

I

. . . . . ._ .,_

Infusion Rate I Cone. of E. Doee of E Base-line

in infuedate i I

infused i Elin Flow , 1

._.

Experimental 100 x

I --

_. ..-^TrY-. ..A_

Cont. of E Flow Exp. Flow in arterial

Base-Line I

I

blood Flow

mlfmin uglml ug lmin mllmin ml/min ng /ml

A 0.197 4.0 0.78 460 340 74 2. 3

B 0.388 4.0 1.55 480 240 50 6. 5

C 0.970 4.0 3. 90 490 6o 12 65.0

D 1.940 4.0 7.80 490 0 0

!

TAKING THE FETAL TEMPERATURE

Until recently the dynamics of the thermal physiology of the human fetus could only be guessed, because a probe for continuous acouiaition of the fetal temperature did not exist.

iF:e solved.the "probe problem" by modifying an existing miniature fetal electrode of the "spiral" type, originally designed for invasive fetal electrocardiotachography. A tiny glass-bead thermistor is "potted" in the "business end" of this electrode using thermally conductive, electrically nonconductive epoxy. Another thermistor is used to senae the maternal temperature at any site.

Two temperature monitors, consisting of two highly accurate thermistor-controlled pulse-train oscillators employing pulse-rate modulation and optical isolation, are connected to the fetal and maternal thermistors. The monitor outputs, proportional to the thermistor temperatures, are recorded on a 'strip chart as are the fetal heart rate (generated from the electrocardiographic signal obtained by the fetal electrode) and the uterine activity.

GEORGE C. BELL Major, USAF, MC Chief, Obstetric Anesthesia Section Anesthesiology Service Department of Surgery Wilford Hall USAF Medical Center Aerospace Medical Division (AFSC) Lackland Air Force Base, Texas 78236

Clinical Instructor of Anesthesiology Department of Anesthesiology University of Texas Medical School at San Antonio San Antonio, Texas 78229

WALTER U. BROWN, JR., M.D.

(1

Department of Anesthesiology Boston Hospital for Women

Instructor in Anaesthesia Harvard Medical School

: / I : :

221 Longwood Avenue Boston, Massachusetts 02115

.

INTRODUCTION TO THE ELECTRONIC CALIPER: APPLICATION OF INSTANTANEOUS

HEART RATE MONITORING

IN ADULT MEDICINE

SUMMARY

Instantaneous heart rate (IHR) patterns have been shown to be of considerable value

in the diagnosis of fetal distress and arrhythmia during labor. Application of this

technique to adults is ,presented here. Normal IHR patterns are presented and compared

to those seen in atria1 fibrillation, demand pacing, Wenckebach phenomenon, and following

administration of atropine'and lidocaine. IHR patterns characteristic of atria1 and ven-

tricular ectopic rhythms are described (including parasystole, fixed coupling), and

clinical applications suggested.

Barry S. Schifrin S. Kennedy R.J. Myrick

A NEW METHOD OF FETAL MONITORING

A new method of processing fetal electrocardiographic

signals obtained from abdominal skin electrodes in both high risk

and normal obstetric patients at the Lying-In Division of the

Boston Hospital for Women is described. The method provides

fetal cardiac rate tracings which are identical to those achieved

using a fetal scalp electrode. A combination of analog filter-

ing and a special purpose digital processor rejects noise and

tracks fetal signals at very small signal-to-noise ratios. The

digital processor also monitors the quality of the signal being

received from the electrodes and suppresses printout during noise

bursts.

The method has been particularly effective in obtaining

objective fetal information in early labor, and has been sucoess-

fully used to evaluate fetal heart rate variability in the ante-

partum period in high risk patients.

Data from a pilot study, comparing tracings obtained

from both maternal skin electrodes and fetal scalp electrodes in

various types of obstetric patients, are presented.

John M. Leventhal, M.D.* George C. Bell, M.D.* Walter U. Brown, Jr., M.D.-

Departments of Obstetrics and Gynecology and Anesthesia Boston Hospital for Women

BLOOD LOSS IN CESAREAN SECTION A COMPARISON OF BALOTBANE, FLUROXENE, AND REGIONAL ANESTHESIA

Miles D. Hyman

The purpose of our study was to challenge the concept that halothane or _.

\ other halogenated inhalation agents increase the amount of blood loss at cesarean

section. Too many clinical impressions were evident that halothane anesthesia did

not increase blood loss during cesarean section.

Our study consisted of 24 patients undergoing cesarean section for a variety

of reasons. Patients included in this group were repeat elective sections not

in labor, repeat sections in labor, sections for DPD, and sections for fetal distress.

The blood volume was determined utilizing the Evans Blue Dye technique in which

the plasma space is identified and blood volume is calculated.

General anesthesia consisted of nitrous oxide 5 liters, oxygen 5 liters, and

halothane b% or fluroxene 2%. Regional anesthesia consisted of either spinal or

epidural utilizing tetracaine for the former and xylocaine for the latter. The

mean blood loss from halothane was 1388 + 595 ml. The mean blood loss from

fluroxene was 1295 + 520 ml. The mean blood loss from regional anesthesia was

1232 + 453 ml. The differences between these blood losses is not statistically

significant.

Apgar scores done at 1 and 5 minutes were 8 for halothane, 8 for fluroxene,

and 8 for regional anesthesia with comparable scores at 5 minutes. Obviously,

these numbers are not statistically

It is generally our impression

blood loss during cesarean section.

significant.

that neither halothane nor fluroxene increases

At present, we are investigating the concept

of light anesthesia so that we can document evidence that our patientswere I MAC

or greater.

BLOOD LOSS 2,000

.

_ 1,500

!\ . iT’

1,000

500 ;

ii

: I 1 : ’ I

:520

Fluroxine Regional Halothane .

Fig. I The Difference in Blood Loss is Not’ Statistically Signif icant

IATROGENIC FETAL DISTRESS

Barry S. Schifrin Beth Israel Hospital

Harvard

The potential dangers of coamionly employed obstetrical and anesthesia

techniques during labor are presented. Definition of the condition of the

individual fetus is a prerequisite for evaluating the effects of any obstetrical

or anesthetic technique. Avoidance of the supine position, careful control

of oxytocin infusion, scrupulous attention to details of technique and drug

dosage will likely contribute to improved fetal and maternal outcome. .

:

SEROTON I N SCREEN I EIG OF NE\JEORFI I HFANTS

A New Approach for the Detection of Mental Retardation

Mary Coleman

The development of a high yield neonatal serotonin screening test to

detect a group of diseases causing mental

Columbia Hospital for Women in Washington ,

Georgetown University Department of Pedia t

ific approach than present neonata t different scient

disease entities.

One sample of blood for the endogenous level of serotonin taken by heel

retardation is underway at the

D.C. in association with the

rics. This new test is based on

I

stick may detect the following diseases:

testi.ng of muI tipie

Low levels: PKU, histidinemia, Down’s syndrome, Cornelia deLange syndroe

I

High levels: Infant hypothyroidism, infantile spasm syndrome with retardation, high serotonin syndrome with retardation, infantile autism, “cerebra1 palsy” when retardation is present, maternal rubella, kernicterus.

Treatments designed to amel iorate or correct mental retardation are available

in some of these disease entities. This is the only screening test routinely

,: 1

detecting cretins.

The.explanation of why the ‘platelet serotonin.level is :

diagnosis lies in the concept of a partial *functional model

appears to be a partial model for the serotonerglc neuron.

useful in neurological

sys tern. The platelet

Both laboratory and

I clinical dyidence have shown that sim iar factors effect actice transport and

intracellular binding of serotonin in the platelet and in the serotonergic

neuron. The proposed serotonin screening test hopes to utilize this relationship

for effective early screening of. neonates.

Early results show detectlon of 1.6% of all newborns, in a normal nursery

;i ]I !,

8, /; i, ,, I:

as potentially retarded infants.

In each patient, one sample of bloodtaken by heel stick is analyzed for

t total 5-hydroxyindoles by a modi.fied fluorometric procedure.

ABRUPT10 PLACENTA

FETAL SEQUELAE

Abe Fosson

At the University of Kentucky Medical Center over an 8 year period

(1963-1971) 2.3% of 8,702 deliveries were complicated by early separation

of a normally placed placenta. Fetal death, 18X, neonatal death, lo%,

neonatal morbidity, 23%, complicated these pregnancies. The most common

problems in the live born infant were depression at birth and the Respiratory

Distress Syndrome. Poor outcome was associated with low birth weight, low

gestational age, and low Apgar scores. Skilled resuscitation and careful

observation is recommended in all of these infants.

MATERNAL AND NEONATAL EFFECTS OF 2% HEPIVACAINE FOR

PERIDURAL ANESTHESIA IN LABOR AND DELIVERY

Richard B. Clark, M.D., AFACOG Gary L. Jones, M.D. David L. Barclay, M.D., FACOG Ferdinand E. Greifenstein, M.D. and with the technical assistance of Paul E. McAninch, Jr., B.S.

The effect of mepivacaine on the neonate was studied in 30 infants,

whose mothers had received peridural anesthesia for labor and delivery.

Both maternal and fetal levels of mepivacaine were determined. The mean

level in the umbilical vein at delivery was 2.61 mcg/ml; that of the

maternal vein, 3.47 mcg/ml. Six of the 30 infants were depressed

(l-minute Apgar score of 6 or less). Eleven infants had umbilical vein

blood levels above 3 mcg/ml. Only 3 of these were depressed. In addition,

10 other women were given mepivacaine 2% for epidural anesthesia for labor

and delivery, but for technical reasons, mepivacaine concentrations were

not obtained. Only 1 of these 10 infants was depressed. As no toxic

threshold was reached, recommendations could not be made as to the maximum

allowable dose of mepivacaine for peridural anesthesia. In healthy young

women with uncompromised fetuses depression was not seen even with doses up

to 16 mg/kg. It would seem prudent, however, to attempt to restrict the

total dose to 10 to 12 mg/kg, or less.

,

Obstetrical Meperidine Usage and Subsequent Infant Development

Brackbill, Y., Abramson, D., Kane, J., & Manniello, R. L.

Recent studies (Bernal h Richards 1972, Dowes, Brackbill,

Conway & Steinschneider 1970, Mednick 1970,137l) have indicated

that obstetrical medication changes infant psychophysiological

functioning. This study evaluated the hypothesis that obste-

trical analgesia of itself is an important determinant of

psychophysiological functioning in infants. The evaluation was

carried out by choosing as subjects infants born to women who

had received the same type of anesthetic and the same type of

analgesic but differing amounts of this analgesic. lleperidine

was the analgesic chosen for use in this study because it

most commonly used analgesic in the United States-at this

and therefore, the most representative.

is the

time

Subjects were‘25 clinically normal, term infants delivered

vaginally in vertex presentation of healthy mothers receiving

uncomplicated epidural anesthesia of 10 cc 2% prilocaine. /

Meperidine administered intramuscularly to the mothers served

as the independent variable with 11 mothers receiving no

meperidine; 4 mothers, 50 mg-; 5 mothers, 75 mg; 4 mothers,

100 mg; and 1 mother, 150 mg. Testing was carried out on

,the first, second and third day of the infants* lives in a quiet

room adjacent to the nursery by experimenters who'were blind

as t ala edication condition and whose interjudge reliability was

.90 or greater for the testing procedures used.

There were four dependent measures in the experimental

procedure. Two of these measures, habituation of the orienting

: I

reflex to a sound stimulus and the Graham Zluscle Tension

Subscale, had previously been shown to be sensitive to the

effects of obstetrical medication (Llowes ct al., 1370) and were

good indices of infant performance. The Brazelton Scale

(Brazelton, unpublished form), developed for clinical purposes,

held promise.as a research instrument. Meperidine level deter-

. . mination (Goldbaum, personal communication 1371) measured the

amount of drug t!lat having crossed the placenta still remained

in the infant's system.

Results showed that infants whose mothers had been medicated

with mepcridine performed significantly more poorly than infants

whose mothers had received no medication. That is, the develop-

mental pattern of the infant was degraded by the administration

of even small amounts of an analgesic to the mother prior to

delivery.

The most sensitive of the dependent measures and the

measure directly correlated with analgesic dose CP=.SSl) and

analgesic dosage time Cp=.731) was the habituation of the orien-

ting reflex. This measure is an index of inhibitory capacity.

Infants of mothers receiving no meperidine habituated twice as

fast as infants of mothers receiving meperidine. These results

indicate that inhibitory function, so vital to appropriate

adaptation of the organism, is especially vulnerable to drug

disruption. The remaining measures serve to underscore and

emphasize these findings.

A hi& ri s?: pr"L'nx?lcy

of reproductive cas:Js.lties.

fi13s’i’pp 1-y L _,.

scrx.ninC; systxm can predict the subsequent occurrence

This prospcc-&i.vc stutiy ini:ti.alI 1: nszxsscd 738 pree;n.znt patients and their

newborns for 51 prcrxtal, II@ in-!,rzpal*lum si:3. 35 neonztnl non-optimal conditions.

In the first ana>~uis of this dctci each of thos e non-optimal conditions was arbi-

trarily assigned a xxi&t (1, 5, IO) dcpc::dir:; upon the ___ x~~32d importace of each

condition i-n ;JrCdiCi;inS nconats.l zorbid<_ty and mortz9ity. Patients with a total

score of less th,an IO were consir;crcd lox A.::? whereas those with scores of IO or -_. -

more were considered hi,+: r!_s!r. 'L'ilblc I tLxxrizcs -I_- the association between this

arbitrary risk status snd subscc_::en'; neonatal morbidity, mortality and one year

developmental score.

TAl3I.E I

PATIEN!!@ .I msf[ STrniTs NEiNATAL ~~~OPTAIJITY I-Year Infent 140RlxDITY Follow-Up

_No. Fercent Prenntal Intrxartum Go. l'crc~ yc? -.-I- _.-__-_ Jtite* xpan Dcvcl. Saore*~

340 JIG L4EJ LaJ 22 6.5 1 106 + IO 135 18 HIW A -a{.! 16 1114

11.8 3 2: 105 t 15 20 idI DIIoIi 35 2k.3 5 35 88 + 12

119 Ii IiIGII IDGII 42 G-5

35.0 ?Y

si 145' 15.6!

91 L 13 25 --pHw

* Per 1000 live births *.* Sixty infants followed to one year; scores are means + one standard deviatic - I&zan p?rina'*l mortality rate

’ Total neox~i;xl .;.or'u.i:ii:, .

,A3 risk incrcnsco pcrinlr-l.:ll Jm5rbidit.y and mortali-i;;r increases, and infant

development scores fall. Paticni;s xri.i,h hir,t?/iri& risk have the Sreatest likelihood

of having a sick nconato, a perinataldeath, or an infant rdth.a lower develop-

mental score at one year (p - 4 0.025).

The next analysis of the data examined the associations existing between

prenatal'risk factors and risks of the intrapartum and n&natal periods. Table II

2. Abstrac-t

indicates correlations

condition at one point

hood of the occurrence

the perinatal period.

FwmKrxL --- Previous stillborn

with :i-, := < 0.05. Thus the occurrence of a non-optinal

durin:: the pregnancy significantly increases the likeli-

of o-Lhcr aosociatcd non-optirul conditions later on in

TN3IJ.3 II

.IDJ?MPARTW NEZONATAb

Abnonml presentation 14econium aspiration, hypoCly- cumin ‘and hypocalcemia

_..--I-.-

Previous premature Prematurity . Prc: Yturitjj, RDS --- _.--____-_ Previous neonatal Abnormal presentation Fetal anomalies, dysmaturity

death -- - Diabetes Secondary arrest, Low apgar, resuscitation,

I shoulder dystocia RI);, ueconium aspiration - -

Vaginal spotting Dysfunctional l~&or, Anemia abruptio placenta

--IL snlol&lC Premature R.O.M. , . hYOIM2

prcnatixity -- -

Kultiple prc~nancy Premature H.O.M., ilyS;.72tW?ity, low apgar, prcx?.aturity s;;;)i:is

History cystitis Toxemia, abruption, Resuscitation, prematurity, p_recaturity scysi.s

Acute pyolo PEil?tU ?:iQr Low ai>gax*, RDS .--_- Acute cystitis 14onc . None -

.Finally, stcpwise fir*ltiple rcCrcssion analysis indicates

I .1 (p = 4 0.001) relations?tip bctucen lcn&h of neonatal hospital

individual total pronatal, intrapartum and/o..* neonatal score.

a ci.Cnificant

stay and

Thus prenatal,

intrapartm or neonatal scores can predict neonatal morbidity as defined by

i neonatal days in hospital.

Current analysis is ox&ning the data without the addition of the

arbitrarily assiCncd weights. %Jeights KU~ be assimed according to the

actual importance of the conditions as determinants of subsequent morbidity.

I

3. Abstract

! I

./

:. i

: !

.\

In conclusion, clasaificication of obstetrical populations using multiple

risk factors is usefkl in predicting intrapartwn and neonatal morbidity,

perinatal mortality and the subsequent early develomnental potential of the

infant. Identification of the high risk pregnancy could result in the early

recognition and prevention of specific non-optima1 conditions.

. .

_ .

;i

.‘!

CESARRAN SECTION ANESTHESIA FOR VAGINAL DELIVERY

Donald M. Sherline, M.D. Patricia F. Norman, M.D. Department of Obstetrics and Gynecology and Anesthesiology University of Mississippi School of Medicine

A satisfactory form of general anesthesia is needed in obstetrics to

be used in: 1) those patients not accepting conduction anesthesia for

vaginal delivery and being equally unwilling to undergo delivery without

anesthesia; 2) in those situations where satisfactory conduction anesthesia

is not available; and 3) in selected cases where general anesthesia would

be the anesthesia of choice.

Faced with the task of teaching general anesthesia for vaginal delivery

to student nurse anesthetists and espousing the philosophy that cyclopropane

anesthesia is no longer acceptable because of its explosive hazard, balanced

general anesthesia was used for uncomplicated vaginal delivery.

Standard cesarean section general anesthesia technique was used. The

patient was anesthetized with intravenous Pentothsl, succinylcholine and the

endotracheal tube put in place. Maintanence was then continued with nitrous

oxide and oxygen anesthesia.

The time between induction of anesthesia and delivery of the infant

was noted and correlated with the Apgar scores and general condition of the

baby at one and five minutes. Obstetrical and anesthetic complications

were noted.

. . .

LOCAL OR GENERAL ANESTHESIA FOR OUTPATIENT LAPAROSCOPY?

J. I. Fishburne, M. D. .I. F. Hulka, M. D.

Departments of Obstetrics and Gynecology and Anesthesiology University of North Carolina

During the past two years, laparoscopic procedures have been done at

the University of North Carolina using both general and local anesthetic

techniques. It was learned that in the cooperative patient, diagnostic

laparoscopy could be done easily and comfortably under local anesthesia with

mild systemic sedation - analgesia. Because of the two puncture technique

and the use of electro-cautery, laparoscopic sterilizations were performed

solely under general anesthesia.

In the last three months of 1972, a new sterilization technique employing

a tubal clip, applied through a single puncture, has been employed. This

study was designed to evaluate different approaches to local anesthesia for

this procedure.

Anesthetic Procedure:

I .;

: : _’

Unpremeditated patients are brought to the outpatient OR and sedated with

Valium 10 mgm I.V. and Fentanyl 0.1 mgm I.V. A paracervical block using 20 cc

of 1% xylocaine is.administered and a controlling tenaculum is placed in the

uterine cervix. An infraumbilical field block is done with 10 cc of 1% xylo-

Caine. After insertion of the laparoscope trocar, one Fallopian tube is sprayed

with 4% xylocaine. Clips are then applied and at each step of the procedure,

the patient is asked to rate potentially painful occurrences on a scale of

0 to 4 (See appended.protocol and evaluation sheet).

Preliminary data suggest that the majority of patients experience pain

characterized as "none" or slight pain (0 or 1 on O-4 scale). Data will

be supplied to define precisely which manipulations cause pain, and conclusions

with respect to technique and efficacy of local anesthesia will be presented. c 4 _ .-..

JIF:ms l/12/73

LOCAL LAPAROSCOPY ANESTHESIA EVALUATION SHEET

NAME: DATE:

UNIT NUMBER: AGE:

Tube Sprayed: (Circle one) R L

Analgesia: (1) VALIUM: 10 mg. 15 mg. 20 mg.

(2) PENTANYL: 0.1 mg. 0.15 mg. 0.2 mg.

(3) PARACERVICAL BLOCK: Yes No

Complications: (1) NAUSEA: Yes No (2) VOMITING: Yes No (3) SYNCOPE: Yes No (4) OTHER:

Analgesia Evaluation:

Pain Rating: Explanation of numbers used in rating below: O= no pain _. l= slight pain 2~ moderate pain 3= severe pain 41 extremely severe

Circle one number for each rating.

1. Intravenous Insertion: 0 1 2

2. Paracervical Block:

3. Skin Elevation:

4. Insufflation:

5. Trochar Insertion:

6. Uterine Motion

7. Tube-Pain Rating:

8. Overall Pain Rating:

9. Patient Acceptance:

.

01 2

0 1' 2

01 2

01 2

012

= 0 12 = 0 12

012

0 l-2

3

3

3

3

3

3

3 3

3

3

4 4

4

4

Would you recommend this procedure to a friend? Yes No

comments:

Part 1. Analgesia:

(a)

(b)

PROTOCOL FOR CLIP LOCAL ANESTHESIA STUDY

Valium = 10 - 20 mg. IV

Fentanyl - 0.1 - 0.2 mg. IV

Part 2. Local Anesthesia:

(a) PCB = 200 mg. Xylocaine (20 cc. of 1% plain Xylocaine)

(b) Infiltration = 100 mg. Xylocaine (10 cc. of 1% Xylocaine)

(c) Topical on one tube: 2 cc. of 4% Xylocaine

Topical application to ONE TUBE ONLY. Wait one minute before applying clip.

Use L Tube if Unit Number ends with an Odd Number.

Use R Tube if Unit Number ends with an Even Number.

Tell patient when @, and when & tubes are clipped.

Anesthetist should score patient's pain and should not know which tube is sprayed so that there is no investigator bias.

Have patient rate the following on a scale of 0 1 2 3 4:

Pain of:

(1) Intravenous insertion (2) Paracervical block (3) Skin elevation (4) Insufflation (5)' Trochar insertion

;;', ;~;;~l'~"~nd @

Rate overall procedure pain as 0 1 2 3 4.

Also rate patient's acceptance.

Part 3. Local Anesthesia without Paracervical Block:

Same as Part 2 but omit PCB.

i I

UTERI NE PRESSURE MONi TORI NG DURING FLUROXENE ANESTHESIA

lraj Zargham, M.D., Stephen R. Leviss, M.D., and Gertie F. Marx, M.D.

From the Departments of Anesthesiology and Obstetrics-Gynecology of the Albert Einstein College of Medicine

Fol lowi ng delivery of infant and placenta under pudendal block with

10 ml of 2% chloroprocaine, a 2 ml intrauterine balloon was inserted into

the uterine cavity and connected to a pressure transducer and Physiograph

recorder. After a control tracing was obtained for 10 or 20 minutes, the

patient was induced into, anesthesia with a sleepdose of thiopental. Fluro-

xene was then administered by mask in either a 2.4 or 3.6 volume per cent

circle inflow concentration with 6 1 iters/minute of oxygen for 20 or 30

minutes. Arterial blood samples for fluroxene 1 eve1 determination were‘

taken at S-minute intervals. At the and of the study, a pitocin infusion

was started and the effect on uterine contractil i ty observed.

While the 2.4

slight decrease in

cent concentration

volume per cent infiow concentration led to only a

spontaneous uterine contractility, the 3.6 volume per

resulted in a significant reduction. However, the

response to pitocin was not blocked. Correlation of arterial blood fluro-

xene levels and uterine contractility will be’presented;

(Informed consent was obtained on admission to the labor suite.)

Cardiovascular Effects of Multiple Drugs Administered During Labor and Delivery

Toshio J. Akamatsu, M.D., Kent Ueland, M.D., Donald Van Nimwegen, M.D., John J. Bonica, M.D., Marlene Eng, M.D., Department of Anesthesiology and the Anesthesia Research Center and the Department of Obstetrics and Gynecology, University of Washington School of Medicine, Seattle, Washington

The cardiovascular effects of inadvertent local anesthesic-epinephrine intravenous administration is described along with the effects of immediate chloropromazine administration for treatment of the observed cardiovascular response. Slides will be presented showing the intra-arterial: continuous pressure, continuous central venous pressure, continuous electrocardiogram and the cardiac outputs at indicated time periods. The cardiovascular response to the administration of oxytocin as measured by the same techniques are also described. The authors conclude that prompt therapy of hypertension resulting from inadvertent epinephrine injections can be safely and rapidly accomplished utilizing chloropromazine. In addition, the administration of oxytocin although consistently results

rarely produces moderate to severe drops in pressure, in minor depression of the cardiovascular system.

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