Abdominoplasty under Spinal Anesthesia: A Feasibility Study.

OBJECTIVES: Abdominoplasty is a very common surgery nowadays and mainly performed as an office-based procedure. Spinal anesthesia is assumed to be safer than general anesthesia in such operations. The aim of this study is to compare between spinal and general anesthesia for abdominoplasty. PATIENTS AND METHODS: Two hundred patients undergoing abdominoplasty, American Society of Anesthesiologists physical status classes I and II, were enrolled in this randomized prospective study. One hundred patients were operated upon under general anesthesia (Group G) and another one hundred patients under spinal anesthesia (Group S). Any intraoperative complications such as hypotension, bradycardia, pain, shivering, nausea, and vomiting related to anesthesia were managed and recorded. Visual analog scale was used to assess postoperative pain severity and the need for analgesia to be administered till 12 h postoperatively.
RESULTS: There was no significant difference as regards patient's satisfaction in both groups although it was lower in Group G than in Group S. There were significant differences in between both groups as regards postoperative nausea and vomiting, early demand for analgesic and total dose of pain killer consumed in 12 h postoperatively which were higher in Group G than in Group S.
CONCLUSION: Spinal anesthesia can be an effective anesthetic technique for office-based abdominoplasty with less postoperative complications when compared with general anesthesia for short procedures with no extensive dissection and positioning.

INTRODUCTION

Abdominoplasty is designed to remove fat, skin laxity, and excess skin with the abdominal skin flap. It is moderately an invasive extraperitoneal procedure and often with liposuction. Ambulatory office-based abdominoplasty procedures have recently increased owing to lower cost and global availability of plastic surgeons in addition to better and safer anesthetic techniques.[1]

Although general anesthesia is frequently used for abdominoplasty, it also can be operated upon safely under subarachnoid or epidural anesthesia.[234] Subarachnoid anesthesia is safer, easier to be carried out, predictable, and of lower cost than epidural or general anesthesia.[5]

-Spinal anesthesia has many advantages such as preemptive analgesia, better control of pain, suppression of the surgical stress response, preservation of perioperative immune function, preservation of oxygenation and pulmonary functional residual capacity and improved visceral vascular flow in addition to reduction in the incidence of venous thrombotic disease and hence pulmonary embolism as it facilitates early ambulation.[678] As pulmonary embolism remains the greatest cause of morbidity and mortality in abdominoplasty surgery so by lessening its rate of occurrence spinal anesthesia adds great benefit to the patient.

The addition of adjuvant drugs to local anesthetics provides time for prolonged surgeries, and it is the ideal technique for procedures below T3–T4. Postdural puncture headache (PDPH) decreased up to 0% with the use of small gauge pencil-point spinal needles even in young outpatients.[9]

Little information describes abdominoplasty under spinal anesthesia. Shari and Meland have published their experience with abdominoplasty being performed under spinal anesthesia in case report.[10]

PATIENTS AND METHODS

A randomized prospective study was performed on 200 patients aged 21–55 years of either sex with the American Society of Anesthesiologists (ASA) physical status classes I and II undergoing abdominoplasty in Ain Shams University Hospital in the period from January 2017 to December 2018, after approval by the local research and ethics committee and after obtaining written informed consent from the enrolled patients. This study is registered in ClinicalTrials.com ID NCT03810547.

All patients were assessed in the preoperative period and counseled about general and spinal anesthesia and also about the possibility of conversion to general anesthesia intraoperatively if there is discomfort or persistent pain despite administration of intravenous (i.v.) analgesics or sedatives. Morbid obese patients with a body mass index (BMI) above 35 kg/m2, patients with contraindication to regional anesthesia, such as local infection, coagulopathy, or spine deformity, and patients refusing regional anesthesia were excluded from the study.

By utilizing a computer-created table of arbitrary numbers, the patients were randomly assigned into one of the two groups – Group G: general anesthesia and Group S: spinal anesthesia.

All patients were fasting at least 8 h before the operation. Clear fluids were permitted up to 4 h before surgery. All patients were sedated with oral midazolam 7.5 mg 30 min before arriving to the operation theater.

After arrival to the operating room, the patients were connected to noninvasive monitoring (blood pressure measuring, pulse oximeter, and 5-lead electrocardiogram), and all vital signs were taken and recorded. All patients were guarded against deep venous thrombosis (DVT) by applying sequential compression device (Tyco Healthcare UK Ltd.) with sleeves applied above and below knee (Covidien, Kendall SCD, Express sleeves, USA).

In Group G, anesthesia was induced with ketamine 0.25 mg.kg-1 as a preemptive analgesia, fentanyl 1 ug.kg-1 and propofol 2 mg.kg-1 i.v. Intubation facilitated by cisatracurium 0.15 mg.kg-1 3 min before endotracheal intubation.. All patients were ventilated with intermittent positive pressure ventilation, tidal volume 6–8 mL.kg-1, and respiratory rate 14–18 rate/min. Ventilator parameters were changed accordingly to maintain end-tidal CO2 level between 35 and 40 mmHg. Sevoflurane inhalation was used for maintenance of anesthesia. Once the operation finished, the patient was awakened, extubated, and shifted to postoperative care unit with full monitoring. If the patient developed shivering, so this complication would be recorded and shivering controlled by applying Bair Hugger warming blanket (Bair Hugger, 3M, US) in addition to warm i.v. crystalloid infusion.

In Group S, all patients were infused with 10 mL.kg-1 Ringer's solution 500 mL before anesthesia as preload. The patients were placed in the sitting position, then after proper skin disinfection with alcohol based chlorhexidine (70% isopropyl alcohol + 2% chlorhexidine gluconate), lidocaine1 % 3-5 mL was infiltrated for skin anesthesia at L3 - L4 or L4 -L 5 inter vertebral space. The spinal anesthesia was achieved by using a Whitacre, 25-gauge spinal needle pencil point with introducer (B. Braun Melsungen AG 34209 Melsungen Germany). After aspiration of clear cerebral spinal fluid, heavy bupivacaine 0.5% (Marcaine Spinal Heavy, AstraZeneca, Sweden) 15-20 mg (according to patient's height) with fentanyl 25 ug were injected intrathecally. Then, the patient was allowed to lie down and positioned. Surgery started when the block reached T6 as assessed by cold sensation.

As long as spinal anesthesia was satisfactory, there was no interference with the patient except with i.v. fluids infusion and oxygen 2-4 L/min nasal cannula. In case of restlessness or complaint of pain, midazolam 0.02 mg.kg-1 bolus was given i.v. in addition to ketamine 0.15 mg.kg-1 in 50 mL normal saline was infused i.v. over 10 minutes. Fentanyl (0.5 ug.kg-1) followed by ketamine (0.5 mg.kg-1) were administered i.v. bolus if there was continuous pain or discomfort. In case of intolerable pain or continuous patient discomfort, general anesthesia was induced in the same manner as in Group G.. If the patient suffered from shivering, Bair Hugger warming blanket (Bair Hugger, 3M, US) was laid over the patient's hands and chest to control shivering along with warming crystalloids infusion, and the complication was recorded.

Blood pressure was recorded every minute for 15 min and every 5 min thereafter. Ephedrine 5–10 mg i.v. bolus and a fluid bolus of 250 mL lactated Ringer's solution were used to treat hypotension (systolic blood pressure <90 mmHg). Atropine 0.5 mg i.v. was used to treat bradycardia (defined when heart rate <60 beats/min). Any discomfort (for example, pain, nausea, or itching) during the procedure was recorded, and any need for conversion to general anesthesia was documented.

Perioperative data were collected such as age, gender, height, weight, BMI, ASA physical status class, duration of surgery and anesthesia, intraoperative nausea and/or vomiting, the need for intraoperative analgesia, conversion to general anesthesia, surgeon satisfaction, visual analog scales (VAS) at rest and on ambulation, the total amount of nalbuphine given in the 12 h, time to discharge to home, and patient satisfaction. If nausea persisted after adjustment of blood pressure or the patient vomited, 10 mg metoclopramide was administered i.v. slowly to control vomiting. If vomiting repeated, 4 mg ondansetron was given and can be repeated once again.

Postoperative pain was assessed at rest and on ambulation at 2 h, 4 h, 6 h, and 12 h postoperatively (using VAS which consists of 10 cm horizontal line ranging from 0 = no pain to 10 = intolerable pain). Patients were asked to mark the line vertically at a point which matched their pain.[1112] Time to the first dose of analgesic was recorded. If VAS ≥4, then 0.1 mg.kg-1 nalbuphine (nalbuphine HCl 20 mg in 1 mL ampoule, Amoun Pharmaceutical Co., Cairo, Egypt) was given i.v., and if the score did not reduce within 15–20 min, an additional 0.05 mg.kg-1 nalbuphine was administered. The total dose of nalbuphine consumed by each patient was calculated for 12 h postoperatively.

Discharge readiness to home was assessed using modified postanesthesia discharge scoring system with total score 10. Patients scoring ≥9 were considered fit for discharge home.[13] The patients were allowed to leave to home once they had passed urine, being mobile, no postoperative nausea and vomiting, minimal pain, and had been assessed by the surgeon as being free from any complications. The patients were counseled for signs and symptoms of complications particularly DVT and to ask immediate medical help in case of suspicion.

After discharge, all patients received oral acetaminophen 500 mg every 6 h and ibuprofen 400 mg every 8 h for up to 5 postoperative days. The patient satisfaction score (0–10) was obtained 2 days later by an independent individual using a telephone interview with severe dissatisfied = 0 and fully satisfied = 10.

Statistical analysis

By assuming that spinal anesthesia would diminish postoperative analgesia by 20% more than general anesthesia, a power of 0.8 with α = 0.05 and β = 0.20, so the required enrolled patients would be at least 93 patients.

The statistical analysis was performed using a standard SPSS software package version 20 (IBM, Armonk, NY, USA). Data were presented as mean values ± standard deviation and numbers (%). Mann–Whitney U-test was used to analyze the VAS pain score. Student's t-test was used to analyze the parametric data. Categorical variables were analyzed using the Chi-square test. P < 0.05 was considered as statistically significant.

RESULTS

This study included two hundred patients undergoing abdominoplasty with liposuction. There were 180 females and 20 males. Their age ranged from 25 to 55 years. The weight of all patients ranged from 75 to 105 kg, and BMI ranged from 25 to 34 kg/m2. Patient characteristics and surgical duration are shown in Table 1.

Table 1

Patient characteristics and surgical data

	Group G	Group S	P
Age (years)	39.1±10.2	36.6±8.8	0.0650
Gender (female/male)	92:8	88:12	0.479
Weight (kg)	88.2±7.3	86.9±9.6	0.282
Height (cm)	161.3±6.8	162±7.4	0.197
BMI (kg/m2)	30.11±3.24	29.4±2.76	0.0969
ASA physical status classes
I	78	83	0.475
II	22	17
Surgical duration (min)	185.64±26.8	188.39±27.15	0.4718
Anesthesia time (min)	189.87±31.6	197±28.9	0.0975

Data are expressed as mean±SD or no. P>0.05 is not statistically significant. BMI=Body mass index, ASA=American Society of Anesthesiologists, SD=Standard deviation

Hemodynamic parameters, intraoperative complications, total doses of fentanyl, and ketamine used in addition to the number of patients converted to general anesthesia are illustrated in Table 2.

Table 2

Intraoperative anesthesia data

	Group G (%)	Group S (%)
Number of patients	100	100
Hypotension (<90/60 mmHg)	8 (5)	34 (34)
Bradycardia (HR <50 beat/min)	8 (8)	11 (11)
O2 saturation <90%	0	0
Shivering	0	28 (28)
Nausea	0	25 (25)
Vomiting	0	13 (13)
Need for intraoperative analgesia (n)	0	49 (49)
Conversion to general anesthesia (n)	100	6 (6)

Data are expressed as number, percentage, or mean±SD. SD=Standard deviation, HR=Heart rate

There was significant difference as regard VAS scores at rest and on ambulation at 2 h and 4 h postoperatively. Total nalbuphine dose during 12 h postoperatively was significantly lower in Group S than in Group G [Table 3].

Table 3

Postoperative pain score and total nalbuphine consumption in 12 h

	Group G		Group S		P
	At rest	On ambulation	At rest	On ambulation	At rest	On ambulation
VAS
2 h (IQR)	3 (1)*	4 (1)*	4 (1)	4 (1)	0.006	0.014
4 h	4 (1)*	4 (1)*	4 (1)	4 (1)	0.008	0.007
6 h	4 (1)	4 (1)	4 (1)	4 (1)	0.804	0.781
12 h	2 (1)	2 (1)	2 (1)	2 (1)	0.749	0.767
Total nalbuphine dose (mg) up to 12 h postoperative	18.83±3.79		13.68±3.42*		<0.0001

*There is significant difference P<0.05. VAS scores data presented as median. IQR=Interquartile range, VAS=Visual analog scale

Postoperative complications including nausea, vomiting, and shivering incidence were higher in Group G than in Group S, while urinary retention incidence was higher in Group S than in Group G but without significant difference. No cases recorded with PDPH in Group S and also no cases recorded with signs of DVT in both groups [Table 4].

Table 4

Incidence of postoperative complications

	Group G	Group S	P
Time to the first dose of analgesic	1.11±0.32	1.86±0.87*	<0.0001
Nausea/vomiting	11	2
Shivering	12	7
Time to ambulate (h)	3.21±1.20	2.88±0.92*	0.0303
Urinary retention	13	15
Postdural puncture headache	0	0
Deep venous thrombosis	0	0

Data are expressed as mean±SD or n. *There is significant difference P<0.05. SD=Standard deviation

Patient satisfaction score was higher in Group S than in Group G but with no significance. Time to discharge home was lower with statistical significance in Group S than in Group G [Table 5].

Table 5

Patient satisfaction scores and time to discharge to home

	Group G	Group S	P
Patient satisfaction score	8.3±0.76	8.5±0.81	0.0733
Time to discharge to home (h)	15.93±3.98	14.78±2.49*	0.0152

Data are expressed as mean±SD. *There is significant difference P<0.05. SD=Standard deviation

DISCUSSION

Abdominoplasty is widely operated as an office-based surgery. This study validates the feasibility of the adequacy of subarachnoid anesthesia for abdominoplasty procedures. Some literature recorded that abdominoplasty procedure is correlated with DVT at much higher rates than other plastic surgery.[14]

In this study, we guarded against the occurrence of DVT by well hydrating the patients before, during and after the procedure and also by applying sequential compression device for all patients. No cases presented with signs of DVT in both groups.

It was stated that when feasible, operations more than 3 h preferably to be performed with regional anesthesia if possible because general anesthesia is joined with higher rates of DVT under prolonged procedures.[15] Local and monitored anesthesia care with or without i.v. sedation is superior to neuraxial blockade, and neuraxial blockade is more desirable than general anesthesia as regards patient's safety.[16]

Really, we are supporting such assumption for straightforward procedures, but we found that in prolonged procedures with extensive dissection and flexed positioning under spinal anesthesia, the patient became more distressed and sedation was required in more higher doses which affected their breathing pattern, and this was the main cause why six cases shifted to general anesthesia. In addition, the surgeon spent more time for adjustment and the procedure delayed more. Although it is well known that general anesthesia is associated with more postoperative complications, such as nausea, vomiting, and shivering, than spinal anesthesia, general anesthesia was more comfortable for patient and surgeon with long-time procedures particularly exceeding 3 h with extensive dissection and more flexed positioning.

Regional anesthesia for abdominoplasty is considered to have some preferences compared with general anesthesia. If the patients have tightly closed abdominoplasties, they start to suffer from shortness of breath which may be a guide to the surgeon to reduce the tightness. Patients are awake and oriented and have less postoperative complications.[16] For the successful finalization of abdominoplasty under regional anesthesia, neuraxial blockade must be performed to cover T6 level.

In fact, we did not confront any case with impaired respiration after extensive dissection under general anesthesia. This may be because all our cases were with BMI <35 kg/m2 and young with ASA physical status classes I and II; so, they could withstand such tightness.

The safety of spinal anesthesia had been detailed for other outpatient surgical procedures including laparoscopy.[17] Increased cost due to delayed recovery from spinal anesthesia, primarily due to motor block, had been considered a hindrance to the use of spinal anesthesia in outpatient procedures.

However, the authors found in their prospective randomized controlled trial that recovery profiles were similar in patients undergoing general anesthesia with desflurane and patients receiving spinal anesthesia.[17] Costs, time to administer anesthesia, and recovery times were similar. Of note, postoperative analgesia was required by 50% of general anesthesia group but in no patients in the spinal anesthesia group.

Chilvers et al. compared the cost of small-dose spinal anesthesia with general anesthesia for outpatient laparoscopy.[18] Postoperative analgesia requirements were reduced using spinal anesthesia; however, total cost of anesthesia and recovery were similar between groups.

In this study, we compared spinal and general anesthesia for abdominoplasty. As abdominoplasty nowadays is an office-based procedure, we tried to imitate the same situations and conditions. That is what motivated us to use nalbuphine for postoperative pain as nalbuphine is widely used as pain killer after office-based procedure because it has wide range of safety and less respiratory depression in comparison to other narcotics and is more feasible to be used with day-case surgery.

We found that minimal sedation with spinal anesthesia helps the patient to accommodate the procedure and decrease the feeling of long procedure time. This intraoperative sedation with ketamine and fentanyl not only make the procedure ease for the patient but also helped to delay time for the first dose of postoperative analgesic and probably affecting total dose of analgesia required by patients for 12 h.

No intraoperative or postoperative anesthetic complications great differences between both types of anesthesia although hypotension, shivering, nausea, and vomiting were more evident intraoperatively with spinal anesthesia which are expected complications of spinal anesthesia and could be controlled completely. Urinary retention was higher in spinal anesthesia but also occurred with general anesthesia which is known to be related to neuraxial block in up to 20% of patients.[19]

Prolonged general anesthesia leads to inability of the patients to ambulate independently within short time of recovery to the opposite of spinal anesthesia in which the patient can ambulate independently once recovered from it. This issue not only affected the early ambulation but also early discharge from hospital which is a desired effect for office-based surgeries.

Limitations

This study underwent with the same anesthesia team, but surgical team was not the same. More researches are needed on more broad scale to compare another group with different type of anesthesia which preferably to be epidural anesthesia and to compare postoperative pain and amount of rescue analgesics in all groups.

CONCLUSION

Our study has provided preliminary evidence that spinal anesthesia can be an effective anesthetic technique for abdominoplasty but for short and straightforward procedure preferably not exceeding 3 h. General anesthesia was more comfortable than spinal anesthesia for both the surgeon, and the patient with prolonged cases needed excessive dissection and more flexed positioning.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.